GB 4706.54-2002 Safety of household and similar electrical appliances Particular requirements for walk-behind and hand-held lawn mowers and lawn edge trimmers
Some standard content:
ICS 65. 060.70
National Standard of the People's Republic of China
GB 4706.54—2002/IEC 60335-2-91: 1991 Safety of household and similar electrical appliances-Particular requirements for walk-behind and hand-held lawn trimmers and lawn edge trimmers(IEC60335-2-91:1997,IDT）
Promulgated on June 13, 2002
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
Implementation on March 1, 2003
All technical contents of this part of GB4706 are mandatory. GB 4706.54—2002/1EC 60335-2-91:1997 This part involves the general safety requirements for two major categories of power tools: hand-held and portable. The special safety standards for the sub-category of this type of electric tools that have been developed and issued by the SC61F sub-technical committee of the International Electrotechnical Commission (IEC) are as follows: Special requirements for pedestrian-controlled electric lawn mowers - Special requirements for lawn mowers
- Special requirements for pedestrian-controlled and hand-held lawn mowers and lawn edge trimmers - Special requirements for pedestrian-controlled electric lawn scarifiers and sanding machines Special requirements for hand-held electric garden vacuums, garden air-supply vacuums and garden air-supply fans This part is equivalent to IEC60335-2-91:1997 "Safety of household and similar electrical appliances - Part 2: Particular requirements for pedestrian and hand-held lawn mowers and lawn edge trimmers", and the general safety requirements of this part are GB4706.11998 "Safety of household and similar electrical appliances - Part 1: General requirements" (eqvIEC60335-1:1991 third edition). This part is written in accordance with GB/T1.1-2000 Guidelines for Standardization - Part 1: Structure and writing rules of standards. For IEC60335-2-911997, the following editorial changes have been made to this part: a) In 7.1 of this part, the symbols in accordance with GB/T4269.1 may be used appropriately. ", the original text uses ISO3767:1991 version, and GB/T4269.1-2000, which is equivalent to ISO3767:1998, is used here. b) In 25.7 of this part, the power cord should not be lighter than ", the original text contains "In some countries, these power cords are not applicable, and the power cord should be a soft cord with ordinary hydrogen butadiene rubber sheath (code 245 [EC57)", which is not applicable in my country. c) In Appendix A of this part, the *GB17465.1-199 8 Appliance couplers for household and similar purposes Part 1: General requirements (eqvIEC60320-1:1994)\, there is no reference to 1EC60320-1:1994 in the original text. d) In Appendix AA of this part, * (from the legend of ISO5395)\, the original text is ISO5935, which is wrong. e) In the last line of the column "Safety distance/mm" in Table AA.1 of Appendix AA of this part, \≥850" was originally \>850", which seems to be wrong. Appendix AA
Except Appendix D and Appendix F, this part retains all the appendices of GB4706.1 (Appendix H is an informative appendix, and the others are normative appendices). In addition, the added appendices are numbered as Appendix AA and Appendix BB respectively. Some of the standards in Appendix A\Referenced normative standards have been converted into IEC standards of national standards and are cited according to national standards. This part is proposed by China Electrical Equipment Industry Association; this part is approved by the General Administration of Quality Supervision, Inspection and Quarantine; this part is under the jurisdiction of the National Technical Committee for Standardization of Electric Tools and is responsible for interpretation; the responsible drafting unit for this part is Shanghai Electric Tools Research Institute: the main drafters of this part are Liu Jiang and Li Bangxie. GB 4706.54—2002/1EC 60335-2-91:1997
Electric tools are divided into handheld electric tools and portable electric tools according to their operation methods. The safety requirements of the two are also different. The International Electrotechnical Commission (IEC) SC61F Sub-Technical Committee "Electric Tool Safety" has formulated the IEC60745 series of safety standards for handheld electric tools and the IEC61029 series of safety standards for portable electric tools, which are respectively adopted by the GB3883 series of standards and the GB13960 series of standards. They are the compliance standards for the safety certification of various types of handheld and portable electric tools. As humans pay more and more attention to the protection of the natural environment, the development of electric tools used for gardening operations is extremely rapid. The International Electrotechnical Commission (IEC) SC61F Sub-Technical Committee began to draft the safety standards for walk-behind and handheld lawn mowers and lawn trimmers in 1994. The draft international standard (61F/146/FDIS) was formed in 1996, and the standard text was voted and approved in 1997. The voting report is 61F/227/RD.
There are four types of walk-behind and hand-held lawn mowers and lawn edge trimmers, including walk-behind lawn mowers and lawn edge trimmers, hand-held lawn mowers and lawn edge trimmers. It involves the general safety standards for hand-held power tools and the general safety standards for portable power tools, and the special requirements for walk-behind lawn mowers and lawn edge trimmers. Whether the general safety requirements for hand-held power tools or the general safety requirements for portable power tools are used, there are certain limitations. For this reason, SC61F adopted IEC60335-1.1991 (third edition) Safety of household and similar electrical appliances Part 1, General requirements\ and amendments as general safety requirements when formulating the standard. IECSC61F is a sub-technical committee of the 61st Technical Committee "Safety of Household and Similar Electrical Appliances" that specializes in formulating safety standards for electric tools. Electric gardening tools are a small category of electric tools. Since the third edition of IEC60335-1:1991 has been equivalently adopted by GB4706.1-1998, this part refers to GB 4706.1-1998 for general requirements when IEC60335-291 is equivalently adopted. 1 Scope
GB 4706. 54-2002/IEC 60335-2-91:1997 Safety of Household and Similar Electrical Appliances
Particular requirements for walk-behind and hand-held lawn mowers and lawn edge trimmers GB 4706.1-1998 This chapter in GB4706-1—1998 is applicable except for the following contents. 1.1 This article adds the following content:
This part of GB4706 applies to mains-powered walk-behind and hand-held lawn mowers and lawn edge trimmers, which have a cutting element of non-metallic fiber rope or a freely rotating non-metallic cutter, and are used by a standing operator to mow the lawn with a kinetic energy not exceeding 10J. This part does not apply to scissor-type or rigid-blade lawn mowers or lawn edge trimmers. Note: In this part, hand-held and walk-behind lawn mowers and lawn edge trimmers are collectively referred to as appliances. 2 Definitions
This chapter in GB4706-1—1998 is applicable except for the following contents. 2.2. 9 This article is replaced by the following content:
Normal operation Operation
refers to the operation of the appliance at rated voltage, when the load reaches the required rated input power. The following clauses are added to this chapter:
hand-held
refers to being held by hand, with the assistance of wheels, pulleys or straps. 2.101.2
walk-behind
refers to being supported by the ground and controlled by the operator walking behind. 2.101.3
lawn trimmer
refers to a mowing machine in which the cutting device rotates in a plane approximately parallel to the ground. 2.101.4
awn edge trimuner refers to a lawn-making machine in which the cutting device rotates in a plane approximately perpendicular to the ground. 2. 101.5
cutting means
Cutting device
refers to a mechanical device used to provide cutting operations, which includes one or more cutting elements that rotate around an axis perpendicular to the cutting surface and cut by impact.
2. 101. 6
Cutting element cuttingelement
· Single non-metallic fiber rope or single rotating non-metallic knife. GB4706.54—-2002/IEC 60335-2-91:19972.101.7
Cutting head
The support of the cutting element.
3 General requirements
The contents of this chapter in GB 4706.1-1998 are applicable. 4 General conditions for testing
The contents of this chapter in GB 4706. 1-1998 are applicable. 5 Blank
6 Classification
The contents of this chapter in GB 4706.1-1998 are applicable except for the following contents. 6.1 This clause is replaced by the following content:
The appliance shall belong to one of the following corresponding categories for protection against electric shock: [Class or Class. Verified by observation and corresponding tests.
6.2 This clause adds the following content;
Walk-behind lawn mowers and lawn edgers shall belong to IPX4 type. 7 Marking and instructions
The contents of this chapter in GB4706.1-1998 are applicable except for the following contents. 7.1 This clause is supplemented with the following content:
The appliance shall be marked with the following content:
Warning!
Read the operating manual
Wear goggles
Keep bystanders away
In addition, hand-held lawn mowers and lawn edge trimmers shall be marked with: Do not expose to moisture
Symbols in accordance with GB/T4269.1 may be used appropriately. Except for cast, inlaid or pasted symbols, the color of the symbols shall comply with the provisions of GB2893. It is permitted not to use text markings. Instead, symbols in accordance with Appendix BB may be used. 7.2 The following content shall be used instead:
The instruction manual shall be provided with the appliance. The instruction manual shall include:
a) Where appropriate, the warnings required to be marked on the appliance and their further instructions. Where symbols or pictograms are used on the appliance, their function shall be explained.
If the appliance is not supplied as a complete unit, instructions for proper assembly of the appliance shall be provided. b
Instructions for proper adjustment and maintenance of the appliance, including warnings of the dangers of rotating cutting elements, for example, "Caution 1 Danger 1 All cutting elements continue to rotate after the appliance is switched off". If the parts are consumable (such as cutting wires), the replacement part numbers shall be specified. d)
Instructions for safe operation of the appliance, including: It is recommended to be equipped with a residual current operated protective device (RCD) with an operating current not exceeding 30 mA.
Instructions for use of all controllers.
GB 4706. 54—2002/1EC 60335-2-91:1997 f) Recommendations on the use and type of external wiring (not less than that required in 25.7). g) Where appropriate, the following shall be listed: Before use, check whether the power cord and external wiring are damaged or aged. If the power cord is damaged during use, unplug the appliance immediately: do not remove the power cord before unplugging the appliance. Do not use the appliance if the power cord is damaged or frayed. Read the instruction manual carefully, familiarize yourself with the controls and use the appliance appropriately. Keep external wires away from the cutting elements.
Wear goggles.
Do not allow children or persons who are not familiar with these instructions to use the appliance. Avoid using the appliance when people are nearby, especially children or small animals. Use the appliance only in daylight or under good lighting conditions. It is not allowed to operate the appliance with damaged guards or shields or without them. Only start the machine when hands and feet are away from the cutting device. It is not allowed to install metal cutting elements.
Use only replacement parts and accessories recommended by the manufacturer. Always disconnect the appliance from the power supply when it is unattended. Disconnect the appliance from the power supply before repairing or cleaning. The appliance should be maintained regularly. Repairs can only be carried out by authorized maintenance departments. Be careful of being cut by the blades installed on the appliance for cutting fiber ropes. After extending a new cutting line and before switching on the power supply, return the appliance to its normal operating position.
Always keep the ventilation openings unobstructed.
When not in use, store the appliance out of the reach of children. 8 Protection against contact with live parts
The contents of this chapter in GB4706.1-1998 are applicable. 9 Starting of electric appliances
The contents of this chapter in GB 4706.1-1998 are not applicable. 10 Input power and current
The contents of this chapter in GB4706.1-1998 are applicable except for the following contents. 10.1 Not applicable.
11 Heat
The contents of this chapter in GB4706.1-1998 are applicable except for the following contents. 11.7 This phenomenon is replaced by the following contents:
The appliance reaches a steady state.
12 Blank
3 Leakage current and electrical strength at working temperature13
The contents of this chapter in GB 4706.1-1998 are applicable. GB 4706.54-2002/1EC 60335-2-91:199714 Blank
Moisture temperature resistance
The contents of this chapter in GB 4706.1-1998 are applicable. 16 Leakage current and electrical strength
The contents of this chapter in GB 4706.1-1998 are applicable. 17 Over-knock protection of transformers and associated circuits The contents of this chapter in GB 4706.1-1998 are applicable. 18 Durability
The contents of this chapter in GB 4706.1-1998 are not applicable. 19 Abnormal operation
The contents of this chapter in GB4706.1-1998 are applicable except for the following contents. 19.7 Not applicable.
20 Stability and mechanical hazards
The contents of this chapter in GB 4706.1-1998 are applicable except for the following contents. 20.2 This clause is replaced by the following contents:
All power transmission parts except cutting devices should be guarded to prevent the operator from touching them. When developing the protection system, the principles specified in Appendix AA should be followed. All guards or shields should be either permanently attached or ensured that they will not be removed without the help of workers, or the appliance should be constructed so that it cannot be used without the guard in place. Verify by inspection.
The following clause is added to this chapter:
20.101 Protection of cutting elements
20. 101. 1 Lawn mowers
Lawn mowers shall be protected at least to the position shown in Figure 101 on the operator's side. The horizontal diameter X of the guard shall not be less than the maximum radius swept by the cutting head, and the guard of a walk-behind lawn mower shall be at least 3 mm above the plane of the cutting element, and the guard of a hand-held lawn mower shall be at least 10 mm above the plane of the cutting element. The guard shall cover at least the 45° arc swept by the cutting element when it leaves the handle shaft on the operator's side and the 90° arc swept by the cutting element when it enters the handle shaft on the operator's side, with the apex of the angle located on the axis of the cutting head spindle.
If the protection range is less than 360°, the direction of rotation of the cutting element shall be marked on the lawn mower. Verify by inspection and measurement.
20.101.2 Lawn edge trimmers
Lawn edge trimmers shall be protected at least to the position shown in Figure 102. The radius X of the guard shall not be less than the maximum radius swept by the cutting head. And the guard shall protrude at least 10 mm from the plane of the cutting element. For a lawn edge trimmer in the normal use position, the guard shall cover at least the 90° arc swept by the handle shaft of the cutting element upwards into the operator's side and the 45° arc swept by the handle shaft of the cutting element downwards into the operator's side, in a plane perpendicular to the ground, with the top point of the angle located on the axis of the cutting head spindle.
GB 4706. 54—2002/IEC 60335-2-91:1997 If the protection range is less than 360°, the direction of rotation of the cutting element shall be marked on the lawn edge trimmer. Verify by observation and measurement.
20.101.3 The guard cannot be removed without the aid of a tool. Verify by observation.
21 Strength of machine
This chapter in GB4706.1-1998 is applicable except for the following contents. 21.1 The contents of this article are modified as follows:
The second paragraph of this article is replaced by the following contents: The cutting device guard shall be tested by the test of 21.101, and the cutting head shall be tested by the test of 21.102. Other parts of the appliance are tested by impacting the appliance with the spring impact tester specified in GB/T2423.44. The following clauses are added to this chapter:
21.101 Strength and rigidity of cutting device guard 21.101.1 The brushability of the cutting device guard is tested by applying a force equivalent to the weight of the lawn mower in the most unfavorable direction for 30 seconds. Before the test, the temperature of the tested part is stabilized at the ambient temperature of (20±3)℃. During and after the test, the guard shall not be deformed or fall off, nor shall it show any visible cracks. The screws and retainers shall remain safe and effective, and the requirements of 20.101.1 and 20.101.2 shall still be met. 21.101.2 The strength of the cutting device guard of walk-behind mowers and walk-behind lawn edge trimmers is tested by placing the device on a smooth, brushable surface and impacting it with a steel ball at a possible weak point. Before the test, the temperature of the test piece is set at an ambient temperature of (20 ± 3) °C.
In the three complete machines, a possible weak point of each guard is impacted with a force of (6.5 ± 2)°C. The specimen is placed on a smooth, rigid surface.
The test is performed as follows: For each test, the part of the specimen impacted is different from the other two test parts. The impact is applied with a steel ball with a diameter of (50 ± 0.8) mm (e.g. on a ball bearing). If the test piece is at an angle of 45° or less to the horizontal plane, the ball is allowed to plumb down from a stationary position and hit the guard. Otherwise, the ball is tied with a rope and allowed to swing and fall: the guard is hit. In the above two cases, , the vertical drop height of the ball is (1300 ± 3) mm. After the test, the guard should not fall off and should not show any visible cracks. The screws and retainers should still be safe and effective, and the requirements of 20.101.1 and 20.101.2 can still be met.
21.101.3 The strength of the cutting device guard of a hand-held lawn mower and a hand-held lawn edge trimmer is tested by the following drop test. A complete machine sample is dropped 3 times, so that the guard falls vertically from a height of <900 ± 2) mm to a smooth horizontal concrete floor. In this way, the guard test is the most severe (see Figure 103). After the test, the guard should not fall off and should not show any visible cracks. The screws and retainers should still be safe and effective, and the requirements of 20.101.1 and 20.101.2 can still be met.
21.102 Strength of cutting head
A complete test piece is dropped so that the cutting head falls in a horizontal position onto a rigidly supported horizontal steel plate. The drop height for hand-held mowers and lawn edge trimmers is (900 ± 2) mm and the drop height for walk-behind mowers and lawn edge trimmers is (250 ± 1.2) mm (see Figure 104). During the test, other parts of the appliance may be protected, if necessary, to prevent impact. After the test, the appliance need not be operational. If the appliance is operational, the following test is immediately carried out, the appliance is operated at maximum speed for 30 s with and without cutting elements. If the appliance is not operational and there is no obvious damage to the cutting head, all parts of the user-replaced and removable cutting head are installed on a new appliance, and the new appliance is then operated at maximum speed for 30 s with and without cutting elements. There shall be no loose parts and no visible cracks. GB 4706.54—2002/IEC 60335-2-91:199722 Structure
This clause in GB4706.1—1998 applies except as follows. 22.36 This clause adds the following content:
Hand-held lawn mowers and lawn edge trimmers shall have at least one handle. All hand-held lawn mowers and hand-held lawn edge trimmers with a mass greater than 3.5 kg shall have two handles and the distance between the centres of the handles shall be at least 250 mm.
Note 1: This 250 mm distance measurement does not apply to lawn mowers and lawn edge trimmers with a mass less than or equal to 3.5 kg. In addition, all hand-held lawn mowers and lawn edge trimmers with a mass greater than 6 kg shall have at least one shoulder strap. The mass of the appliance shall be taken from the heaviest condition in normal use and without the cable. The gripping surface length of all handles required by this part of GB4706 shall be at least 100 mm. Note 2: If the size of the part containing the motor reaches 100mm, it can be regarded as a handle. The grip length of a ring or closed ring handle should include all straight sections or the length of the radius of curvature greater than 100mm, as well as all arcs at both ends (or one of the ends) of the grip surface with a length not greater than 10mm. If the straight handle is centrally supported (such as a \T\ shape), the grip length should be calculated as follows: a) For a handle with a circumference less than 80mm (excluding the support), the grip length should be the sum of the lengths of the two parts excluding the support,
b) For a handle with a circumference greater than or equal to 80mm (excluding the support), the grip length should be the total length from one end to the other. The appropriate part of the handle of the control actuator containing the cutting device should be regarded as part of the grip length of the handle. Finger grip or similar overlapping shapes should not affect the calculation method of the grip length of the handle. Verify by observation and measurement calculation.
22.40 The following is added to this clause:
The appliance shall be provided with a control which shall have two independent, distinct actions before the cutting device is actuated, or the control shall be protected against external manipulation. This shall be verified by observation, and it shall not be possible for the control to be actuated by a ball having a diameter of (100 ± 1) mm. The following clause is added to this chapter:
22.101 The cutting device shall consist of one or more non-metallic cutting elements mounted on or extending from a common circular cutting head.
This shall be verified by observation.
22.102 The cutting element shall consist of one of the following: a) non-metallic fibre rope; or
b) non-metallic freely revolving cutter.
For appliances using one or more continuous fibre ropes (wound on a wire tube mounted on the cutting head or other accessory) as cutting elements, a device shall be provided to lengthen the fibre rope and/or automatically limit the rope to the correct operating length after operation of the appliance. Manufacturers shall not supply metallic cutting elements as substitutes for non-metallic cutting elements. Verify by inspection.
22.103 The kinetic energy of the cutting element shall not exceed 10 J. Verify by observation, measurement and test. Before testing and measuring, each cutting element shall be stored for at least 7 days at an ambient temperature of (20 ± 3) °C.
For the purpose of this part of GB 4706, kinetic energy is determined by the following formula: Kinetic energy = 1/2mv2(J)
-.....( l)
Where:
GB 4706. 54—2002/1EC 60335-2-91:1997m—mass of the cutting element with a length of L, in kilograms (kg) (see Figure 105):—maximum linear velocity reached at the midpoint Z of a cutting element with a length of L, in meters per second (m/s). Therefore,
V = 0. 104 7n(c-(L/2)
Where:
Maximum speed with a full coil of rope or a new cutter, in revolutions per minute (1/min) r—the distance from the center of rotation of the cutting head to the outside of the cutting device, in meters (m) L—the measured length of the cutting element, in meters (m). Note: The tolerances conform to the requirements of GB/T1804.
23 Internal wiring
The contents of this chapter in GB 4706.1-1998 are applicable. 24 Components
The contents of this chapter in GB 4706.1-1998 are applicable except for the following contents. 24. 1 This clause adds the following contents;
The switch shall cut off all poles, and the contact of each pole shall have an opening distance of at least 3mm. The switch shall be able to withstand 10 000 operation tests. 25 Electrical connection and external flexible cord
This chapter in GB4706.1-1998 is applicable except for the following contents. 25.1 This article adds the following contents:
The appliance inlet socket should not allow the connection parts that comply with GB17465.1 to be inserted. 25.7 This article makes the following modifications:
The first paragraph is replaced by the following contents: The power cord should be no lighter than:
-Rubber insulated, ordinary rubber sheathed flexible cord GB5013.4 (code 245IEC53)-PVC insulated, ordinary polyvinyl chloride sheathed flexible cord GB5023.5 (code 227IEC53). 26 External fleece conductor terminals
GB 4706.1-1998 27 Grounding measures
The contents of this chapter in GB 4706.1-1998 are applicable. 28 Screws and connections
The contents of this chapter in GB 4706.1-1998 are applicable. 29 Electrical distances, electrical transmission and penetration distances
The contents of this chapter in GB 4706.1-1998 are applicable. -(2)
GB 4706. 542002/IEC 60335-2-91:1997 Resistance to heat, flame and electrical decay
The contents of this chapter in GB 4706.1-1998 are applicable. 31 Rust prevention
The contents of this chapter in GB 4706.1-1998 are applicable. 32
Radiation, toxicity and similar hazards
GB The contents of this chapter in 4706.1-1998 are applicable.The test piece is placed on a smooth rigid surface with an impact of 5 ± 2 mm.
The test is conducted as follows: For each test, the test piece is impacted at a different location than the other two tests. The impact is applied by a steel ball (e.g. on a ball bearing) with a diameter of (50 ± 0.8) mm. If the test piece is at an angle of 45° or less to the horizontal, the ball is allowed to plumb down from a stationary position and hit the guard. Alternatively, the ball is tied with a rope and allowed to swing down: the guard is inserted. In both cases, the vertical drop of the ball is (1300 ± 3) mm. After the test, the guard shall not fall off and shall not show any visible cracks. The screws and retaining brackets shall remain safe and effective, and the requirements of 20.101.1 and 20.101.2 shall still be met.
21.101.3 The strength of the cutting device guard of a hand-held lawn mower and hand-held lawn edge trimmer is tested by the following drop test. A complete machine sample is dropped three times, so that the guard falls vertically from a height of <900 ± 2) mm onto a smooth horizontal concrete floor. In this way, the guard test is most severe (see Figure 103). After the test, the guard shall not fall off and shall not show any visible cracks. The screws and retaining brackets shall still be safe and effective, and the requirements of 20.101.1 and 20.101.2 shall still be met.
21.102 Strength of cutting head
A complete machine sample is dropped so that the cutting head falls in a horizontal position and hits a rigidly supported horizontal steel plate. The drop height for hand-held mowers and lawn edge trimmers is (900 ± 2) mm, and the drop height for walk-behind mowers and lawn edge trimmers is (250 ± 1.2) mm (see Figure 104). During the test, other parts of the appliance may be protected as necessary to prevent impact. After the test, the appliance does not need to be operational. If the appliance is operable, the following test is immediately carried out, the appliance being operated at top speed for 30 s with and without cutting elements. If the appliance is inoperable and there is no visible damage to the cutting head, all parts of the user-replaced and removable cutting head are fitted to a new appliance, which is then operated at top speed for 30 s with and without cutting elements. There shall be no loose parts and no visible cracks. GB 4706.54—2002/IEC 60335-2-91:199722 Construction
This clause of GB4706.1—1998 applies except as follows. 22.36 The following content is added to this clause:
Hand-held lawn mowers and hand-held lawn edge trimmers shall have at least one handle. All hand-held lawn mowers and hand-held lawn edge trimmers with a mass greater than 3.5 kg shall have two handles, and the centre distance between the two handles shall be at least 250 mm.
Note 1: The 250 mm distance measurement does not apply to lawn mowers and lawn edgers with a mass of 3.5 kg or less. In addition, all hand-held lawn mowers and lawn edgers with a mass greater than 6 kg should have at least one shoulder strap. The weight of the appliance should be taken when it is in normal use at its heaviest condition and without a cable. The gripping surface length of all handles required by this part of GB 4706 should be at least 100 mm. Note 2: If the size of the part containing the motor reaches 100 mm, it can be regarded as a handle. The gripping length of a ring or closed ring handle should include all straight sections or the length of the radius of curvature greater than 100 mm, as well as all arcs at both ends (or one of the ends) of the gripping surface with a length not greater than 10 mm. If the straight handle is centrally supported (e.g. T-shaped), the grip length shall be calculated as follows: a) For handles with a circumference of less than 80 mm (excluding the support), the grip length shall be the sum of the lengths of the two parts excluding the support,
b) For handles with a circumference of 80 mm or more (excluding the support), the grip length shall be the total length from one end to the other. The appropriate part of the handle containing the control actuator of the cutting device shall be considered as part of the grip length of the handle. Finger grips or similar overlapping shapes shall not affect the calculation method of the grip length of the handle. Verified by observation and measurement calculation.
22.40 This clause adds the following content:
The appliance shall be provided with a control and the control shall be required to have two independent and distinct actions before the cutting device is actuated, or the control shall be protected to prevent external operation. Verified by observation, and it shall not be possible to actuate the control by a ball with a diameter of (100 ± 1) mm. The following clauses are added to this chapter:
22.101 The cutting device shall consist of one or more non-metallic cutting elements mounted on or extending from a normal circular cutting head.
Verified by inspection.
22.102 The cutting element shall consist of one of the following components: a) a non-metallic fibre rope; or
b) a non-metallic freely rotating cutter.
For appliances using one or more continuous fibre ropes (wound on a wire attached to the cutting head or other accessory) as cutting elements, a device shall be provided to lengthen the fibre rope and/or automatically limit the rope to the correct operating length after operation of the appliance. Manufacturers shall not supply metallic cutting elements that can replace non-metallic cutting elements. Verified by inspection.
22.103 The kinetic energy of the cutting element shall not exceed 10 J. Verified by inspection, measurement and test. Before testing and measuring, each cutting element shall be stored for at least 7 days at an ambient temperature of (20 ± 3) °C.
For the purpose of this part of GB 4706, kinetic energy is determined by the following formula: Kinetic energy = 1/2mv2(J)www.bzxz.net
-.....( l)
Where:
GB 4706. 54—2002/1EC 60335-2-91:1997m—mass of the cutting element with a length of L, in kilograms (kg) (see Figure 105):—maximum linear velocity reached at the midpoint Z of a cutting element with a length of L, in meters per second (m/s). Therefore,
V = 0. 104 7n(c-(L/2)
Where:
Maximum speed with a full coil of rope or a new cutter, in revolutions per minute (1/min) r—the distance from the center of rotation of the cutting head to the outside of the cutting device, in meters (m) L—the measured length of the cutting element, in meters (m). Note: The tolerances conform to the requirements of GB/T1804.
23 Internal wiring
The contents of this chapter in GB 4706.1-1998 are applicable. 24 Components
The contents of this chapter in GB 4706.1-1998 are applicable except for the following contents. 24. 1 This clause adds the following contents;
The switch shall cut off all poles, and the contact of each pole shall have an opening distance of at least 3mm. The switch shall be able to withstand 10 000 operation tests. 25 Electrical connection and external flexible cord
This chapter in GB4706.1-1998 is applicable except for the following contents. 25.1 This article adds the following contents:
The appliance inlet socket should not allow the connection parts that comply with GB17465.1 to be inserted. 25.7 This article makes the following modifications:
The first paragraph is replaced by the following contents: The power cord should be no lighter than:
-Rubber insulated, ordinary rubber sheathed flexible cord GB5013.4 (code 245IEC53)-PVC insulated, ordinary polyvinyl chloride sheathed flexible cord GB5023.5 (code 227IEC53). 26 External fleece conductor terminals
GB 4706.1-1998 27 Grounding measures
The contents of this chapter in GB 4706.1-1998 are applicable. 28 Screws and connections
The contents of this chapter in GB 4706.1-1998 are applicable. 29 Electrical distances, electrical transmission and penetration distances
The contents of this chapter in GB 4706.1-1998 are applicable. -(2)
GB 4706. 542002/IEC 60335-2-91:1997 Resistance to heat, flame and electrical decay
The contents of this chapter in GB 4706.1-1998 are applicable. 31 Rust prevention
The contents of this chapter in GB 4706.1-1998 are applicable. 32
Radiation, toxicity and similar hazards
GB The contents of this chapter in 4706.1-1998 are applicable.The test piece is placed on a smooth rigid surface with an impact of 5 ± 2 mm.
The test is conducted as follows: For each test, the test piece is impacted at a different location than the other two tests. The impact is applied by a steel ball (e.g. on a ball bearing) with a diameter of (50 ± 0.8) mm. If the test piece is at an angle of 45° or less to the horizontal, the ball is allowed to plumb down from a stationary position and hit the guard. Alternatively, the ball is tied with a rope and allowed to swing down: the guard is inserted. In both cases, the vertical drop of the ball is (1300 ± 3) mm. After the test, the guard shall not fall off and shall not show any visible cracks. The screws and retaining brackets shall remain safe and effective, and the requirements of 20.101.1 and 20.101.2 shall still be met.
21.101.3 The strength of the cutting device guard of a hand-held lawn mower and hand-held lawn edge trimmer is tested by the following drop test. A complete machine sample is dropped three times, so that the guard falls vertically from a height of <900 ± 2) mm onto a smooth horizontal concrete floor. In this way, the guard test is most severe (see Figure 103). After the test, the guard shall not fall off and shall not show any visible cracks. The screws and retaining brackets shall still be safe and effective, and the requirements of 20.101.1 and 20.101.2 shall still be met.
21.102 Strength of cutting head
A complete machine sample is dropped so that the cutting head falls in a horizontal position and hits a rigidly supported horizontal steel plate. The drop height for hand-held mowers and lawn edge trimmers is (900 ± 2) mm, and the drop height for walk-behind mowers and lawn edge trimmers is (250 ± 1.2) mm (see Figure 104). During the test, other parts of the appliance may be protected as necessary to prevent impact. After the test, the appliance does not need to be operational. If the appliance is operable, the following test is immediately carried out, the appliance being operated at top speed for 30 s with and without cutting elements. If the appliance is inoperable and there is no visible damage to the cutting head, all parts of the user-replaced and removable cutting head are fitted to a new appliance, which is then operated at top speed for 30 s with and without cutting elements. There shall be no loose parts and no visible cracks. GB 4706.54—2002/IEC 60335-2-91:199722 Construction
This clause of GB4706.1—1998 applies except as follows. 22.36 The following content is added to this clause:
Hand-held lawn mowers and hand-held lawn edge trimmers shall have at least one handle. All hand-held lawn mowers and hand-held lawn edge trimmers with a mass greater than 3.5 kg shall have two handles, and the centre distance between the two handles shall be at least 250 mm.
Note 1: The 250 mm distance measurement does not apply to lawn mowers and lawn edgers with a mass of 3.5 kg or less. In addition, all hand-held lawn mowers and lawn edgers with a mass greater than 6 kg should have at least one shoulder strap. The weight of the appliance should be taken when it is in normal use at its heaviest condition and without a cable. The gripping surface length of all handles required by this part of GB 4706 should be at least 100 mm. Note 2: If the size of the part containing the motor reaches 100 mm, it can be regarded as a handle. The gripping length of a ring or closed ring handle should include all straight sections or the length of the radius of curvature greater than 100 mm, as well as all arcs at both ends (or one of the ends) of the gripping surface with a length not greater than 10 mm. If the straight handle is centrally supported (e.g. T-shaped), the grip length shall be calculated as follows: a) For handles with a circumference of less than 80 mm (excluding the support), the grip length shall be the sum of the lengths of the two parts excluding the support,
b) For handles with a circumference of 80 mm or more (excluding the support), the grip length shall be the total length from one end to the other. The appropriate part of the handle containing the control actuator of the cutting device shall be considered as part of the grip length of the handle. Finger grips or similar overlapping shapes shall not affect the calculation method of the grip length of the handle. Verified by observation and measurement calculation.
22.40 This clause adds the following content:
The appliance shall be provided with a control and the control shall be required to have two independent and distinct actions before the cutting device is actuated, or the control shall be protected to prevent external operation. Verified by observation, and it shall not be possible to actuate the control by a ball with a diameter of (100 ± 1) mm. The following clauses are added to this chapter:
22.101 The cutting device shall consist of one or more non-metallic cutting elements mounted on or extending from a normal circular cutting head.
Verified by inspection.
22.102 The cutting element shall consist of one of the following components: a) a non-metallic fibre rope; or
b) a non-metallic freely rotating cutter.
For appliances using one or more continuous fibre ropes (wound on a wire attached to the cutting head or other accessory) as cutting elements, a device shall be provided to lengthen the fibre rope and/or automatically limit the rope to the correct operating length after operation of the appliance. Manufacturers shall not supply metallic cutting elements that can replace non-metallic cutting elements. Verified by inspection.
22.103 The kinetic energy of the cutting element shall not exceed 10 J. Verified by inspection, measurement and test. Before testing and measuring, each cutting element shall be stored for at least 7 days at an ambient temperature of (20 ± 3) °C.
For the purpose of this part of GB 4706, kinetic energy is determined by the following formula: Kinetic energy = 1/2mv2(J)
-.....( l)
Where:
GB 4706. 54—2002/1EC 60335-2-91:1997m—mass of the cutting element with a length of L, in kilograms (kg) (see Figure 105):—maximum linear velocity reached at the midpoint Z of a cutting element with a length of L, in meters per second (m/s). Therefore,
V = 0. 104 7n(c-(L/2)
Where:
Maximum speed with a full coil of rope or a new cutter, in revolutions per minute (1/min) r—the distance from the center of rotation of the cutting head to the outer edge of the cutting device, in meters (m) L—the measured length of the cutting element, in meters (m). Note: The overall length meets the requirements of GB/T1804.
23 Internal wiring
The contents of this chapter in GB 4706.1-1998 are applicable. 24 Components
This chapter in GB 4706.1-1998 is applicable except for the following contents. 24. 1 This clause adds the following contents;
The switch shall cut off all poles, and the contact of each pole shall have an opening distance of at least 3mm. The switch shall be able to withstand 10 000 operation tests. 25 Electrical connection and external flexible cord
This chapter in GB4706.1-1998 is applicable except for the following contents. 25.1 This article adds the following contents:
The appliance inlet socket should not allow the connection parts that comply with GB17465.1 to be inserted. 25.7 This article makes the following modifications:
The first paragraph is replaced by the following contents: The power cord should be no lighter than:
-Rubber insulated, ordinary rubber sheathed flexible cord GB5013.4 (code 245IEC53)-PVC insulated, ordinary polyvinyl chloride sheathed flexible cord GB5023.5 (code 227IEC53). 26 External fleece conductor terminals
GB 4706.1-1998 27 Grounding measures
The contents of this chapter in GB 4706.1-1998 are applicable. 28 Screws and connections
The contents of this chapter in GB 4706.1-1998 are applicable. 29 Electrical distances, electrical transmission and penetration distances
The contents of this chapter in GB 4706.1-1998 are applicable. -(2)
GB 4706. 542002/IEC 60335-2-91:1997 Resistance to heat, flame and electrical decay
The contents of this chapter in GB 4706.1-1998 are applicable. 31 Rust prevention
The contents of this chapter in GB 4706.1-1998 are applicable. 32
Radiation, toxicity and similar hazards
GB The contents of this chapter in 4706.1-1998 are applicable.The requirements of 101.2 are still met.
21.101.3 The strength of the cutting device guard of a hand-held lawn mower and hand-held lawn edge trimmer is tested by the following drop test. A complete machine sample is dropped 3 times, so that the guard falls vertically from a height of <900±2) mm to a smooth horizontal concrete floor. In this way, the guard test is the most severe (see Figure 103). After the test, the guard should not fall off and should not show any visible cracks. The screws and retainers should still be safe and effective, and the requirements of 20.101.1 and 20.101.2 are still met.
21.102 Strength of cutting head
A complete test piece is dropped so that the cutting head falls in a horizontal position onto a rigidly supported horizontal steel plate. The drop height for hand-held mowers and lawn edge trimmers is (900 ± 2) mm and the drop height for walk-behind mowers and lawn edge trimmers is (250 ± 1.2) mm (see Figure 104). During the test, other parts of the appliance may be protected, if necessary, to prevent impact. After the test, the appliance need not be operational. If the appliance is operational, the following test is immediately carried out, the appliance is operated at maximum speed for 30 s with and without cutting elements. If the appliance is not operational and there is no obvious damage to the cutting head, all parts of the user-replaced and removable cutting head are installed on a new appliance, and the new appliance is then operated at maximum speed for 30 s with and without cutting elements. There shall be no loose parts and no visible cracks. GB 4706.54—2002/IEC 60335-2-91:199722 Structure
This clause in GB4706.1—1998 applies except as follows. 22.36 This clause adds the following content:
Hand-held lawn mowers and lawn edge trimmers shall have at least one handle. All hand-held lawn mowers and hand-held lawn edge trimmers with a mass greater than 3.5 kg shall have two handles and the distance between the centres of the handles shall be at least 250 mm.
Note 1: This 250 mm distance measurement does not apply to lawn mowers and lawn edge trimmers with a mass less than or equal to 3.5 kg. In addition, all hand-held lawn mowers and lawn edge trimmers with a mass greater than 6 kg shall have at least one shoulder strap. The mass of the appliance shall be taken from the heaviest condition in normal use and without the cable. The gripping surface length of all handles required by this part of GB4706 shall be at least 100 mm. Note 2: If the size of the part containing the motor reaches 100mm, it can be regarded as a handle. The grip length of a ring or closed ring handle should include all straight sections or the length of the radius of curvature greater than 100mm, as well as all arcs at both ends (or one of the ends) of the grip surface with a length not greater than 10mm. If the straight handle is centrally supported (such as a \T\ shape), the grip length should be calculated as follows: a) For a handle with a circumference less than 80mm (excluding the support), the grip length should be the sum of the lengths of the two parts excluding the support,
b) For a handle with a circumference greater than or equal to 80mm (excluding the support), the grip length should be the total length from one end to the other. The appropriate part of the handle of the control actuator containing the cutting device should be regarded as part of the grip length of the handle. Finger grip or similar overlapping shapes should not affect the calculation method of the grip length of the handle. Verify by observation and measurement calculation.
22.40 The following is added to this clause:
The appliance shall be provided with a control which shall have two independent, distinct actions before the cutting device is actuated, or the control shall be protected against external manipulation. This shall be verified by observation, and it shall not be possible for the control to be actuated by a ball having a diameter of (100 ± 1) mm. The following clause is added to this chapter:
22.101 The cutting device shall consist of one or more non-metallic cutting elements mounted on or extending from a common circular cutting head.
This shall be verified by observation.
22.102 The cutting element shall consist of one of the following: a) non-metallic fibre rope; or
b) non-metallic freely revolving cutter.
For appliances using one or more continuous fibre ropes (wound on a wire tube mounted on the cutting head or other accessory) as cutting elements, a device shall be provided to lengthen the fibre rope and/or automatically limit the rope to the correct operating length after operation of the appliance. Manufacturers shall not supply metallic cutting elements as substitutes for non-metallic cutting elements. Verify by inspection.
22.103 The kinetic energy of the cutting element shall not exceed 10 J. Verify by observation, measurement and test. Before testing and measuring, each cutting element shall be stored for at least 7 days at an ambient temperature of (20 ± 3) °C.
For the purpose of this part of GB 4706, kinetic energy is determined by the following formula: Kinetic energy = 1/2mv2(J)
-.....( l)
Where:
GB 4706. 54—2002/1EC 60335-2-91:1997m—mass of the cutting element with a length of L, in kilograms (kg) (see Figure 105):—maximum linear velocity reached by the midpoint Z of a cutting element with a length of L, in meters per second (m/s). Therefore,
V = 0. 104 7n(c-(L/2)
Where:
Maximum speed with a full coil of rope or a new cutter, in revolutions per minute (1/min) r—the distance from the center of rotation of the cutting head to the outside of the cutting device, in meters (m) L—the measured length of the cutting element, in meters (m). Note: The tolerances conform to the requirements of GB/T1804.
23 Internal wiring
The contents of this chapter in GB 4706.1-1998 are applicable. 24 Components
The contents of this chapter in GB 4706.1-1998 are applicable except for the following contents. 24. 1 This clause adds the following contents;
The switch shall cut off all poles, and the contact of each pole shall have an opening distance of at least 3mm. The switch shall be able to withstand 10 000 operation tests. 25 Electrical connection and external flexible cord
This chapter in GB4706.1-1998 is applicable except for the following contents. 25.1 This article adds the following contents:
The appliance inlet socket should not allow the connection parts that comply with GB17465.1 to be inserted. 25.7 This article makes the following modifications:
The first paragraph is replaced by the following contents: The power cord should be no lighter than:
-Rubber insulated, ordinary rubber sheathed flexible cord GB5013.4 (code 245IEC53)-PVC insulated, ordinary polyvinyl chloride sheathed flexible cord GB5023.5 (code 227IEC53). 26 External fleece conductor terminals
GB 4706.1-1998 27 Grounding measures
The contents of this chapter in GB 4706.1-1998 are applicable. 28 Screws and connections
The contents of this chapter in GB 4706.1-1998 are applicable. 29 Electrical distances, electrical transmission and penetration distances
The contents of this chapter in GB 4706.1-1998 are applicable. -(2)
GB 4706. 542002/IEC 60335-2-91:1997 Resistance to heat, flame and electrical decay
The contents of this chapter in GB 4706.1-1998 are applicable. 31 Rust prevention
The contents of this chapter in GB 4706.1-1998 are applicable. 32
Radiation, toxicity and similar hazards
GB The contents of this chapter in 4706.1-1998 are applicable.The requirements of 101.2 are still met.
21.101.3 The strength of the cutting device guard of a hand-held lawn mower and hand-held lawn edge trimmer is tested by the following drop test. A complete machine sample is dropped 3 times, so that the guard falls vertically from a height of <900±2) mm to a smooth horizontal concrete floor. In this way, the guard test is the most severe (see Figure 103). After the test, the guard should not fall off and should not show any visible cracks. The screws and retainers should still be safe and effective, and the requirements of 20.101.1 and 20.101.2 are still met.
21.102 Strength of cutting head
A complete test piece is dropped so that the cutting head falls in a horizontal position onto a rigidly supported horizontal steel plate. The drop height for hand-held mowers and lawn edge trimmers is (900 ± 2) mm and the drop height for walk-behind mowers and lawn edge trimmers is (250 ± 1.2) mm (see Figure 104). During the test, other parts of the appliance may be protected, if necessary, to prevent impact. After the test, the appliance need not be operational. If the appliance is operational, the following test is immediately carried out, the appliance is operated at maximum speed for 30 s with and without cutting elements. If the appliance is not operational and there is no obvious damage to the cutting head, all parts of the user-replaced and removable cutting head are installed on a new appliance, and the new appliance is then operated at maximum speed for 30 s with and without cutting elements. There shall be no loose parts and no visible cracks. GB 4706.54—2002/IEC 60335-2-91:199722 Structure
This clause in GB4706.1—1998 applies except as follows. 22.36 This clause adds the following content:
Hand-held lawn mowers and lawn edge trimmers shall have at least one handle. All hand-held lawn mowers and hand-held lawn edge trimmers with a mass greater than 3.5 kg shall have two handles and the distance between the centres of the handles shall be at least 250 mm.
Note 1: This 250 mm distance measurement does not apply to lawn mowers and lawn edge trimmers with a mass less than or equal to 3.5 kg. In addition, all hand-held lawn mowers and lawn edge trimmers with a mass greater than 6 kg shall have at least one shoulder strap. The mass of the appliance shall be taken from the heaviest condition in normal use and without the cable. The gripping surface length of all handles required by this part of GB4706 shall be at least 100 mm. Note 2: If the size of the part containing the motor reaches 100mm, it can be regarded as a handle. The grip length of a ring or closed ring handle should include all straight sections or the length of the radius of curvature greater than 100mm, as well as all arcs at both ends (or one of the ends) of the grip surface with a length not greater than 10mm. If the straight handle is centrally supported (such as a \T\ shape), the grip length should be calculated as follows: a) For a handle with a circumference less than 80mm (excluding the support), the grip length should be the sum of the lengths of the two parts excluding the support,
b) For a handle with a circumference greater than or equal to 80mm (excluding the support), the grip length should be the total length from one end to the other. The appropriate part of the handle of the control actuator containing the cutting device should be regarded as part of the grip length of the handle. Finger grip or similar overlapping shapes should not affect the calculation method of the grip length of the handle. Verify by observation and measurement calculation.
22.40 The following is added to this clause:
The appliance shall be provided with a control which shall have two independent, distinct actions before the cutting device is actuated, or the control shall be protected against external manipulation. This shall be verified by observation, and it shall not be possible for the control to be actuated by a ball having a diameter of (100 ± 1) mm. The following clause is added to this chapter:
22.101 The cutting device shall consist of one or more non-metallic cutting elements mounted on or extending from a common circular cutting head.
This shall be verified by observation.
22.102 The cutting element shall consist of one of the following: a) non-metallic fibre rope; or
b) non-metallic freely revolving cutter.
For appliances using one or more continuous fibre ropes (wound on a wire tube mounted on the cutting head or other accessory) as cutting elements, a device shall be provided to lengthen the fibre rope and/or automatically limit the rope to the correct operating length after operation of the appliance. Manufacturers shall not supply metallic cutting elements as substitutes for non-metallic cutting elements. Verify by inspection.
22.103 The kinetic energy of the cutting element shall not exceed 10 J. Verify by observation, measurement and test. Before testing and measuring, each cutting element shall be stored for at least 7 days at an ambient temperature of (20 ± 3) °C.
For the purpose of this part of GB 4706, kinetic energy is determined by the following formula: Kinetic energy = 1/2mv2(J)
-.....( l)
Where:
GB 4706. 54—2002/1EC 60335-2-91:1997m—mass of the cutting element with a length of L, in kilograms (kg) (see Figure 105):—maximum linear velocity reached at the midpoint Z of a cutting element with a length of L, in meters per second (m/s). Therefore,
V = 0. 104 7n(c-(L/2)
Where:
Maximum speed with a full coil of rope or a new cutter, in revolutions per minute (1/min) r—the distance from the center of rotation of the cutting head to the outside of the cutting device, in meters (m) L—the measured length of the cutting element, in meters (m). Note: The tolerances conform to the requirements of GB/T1804.
23 Internal wiring
The contents of this chapter in GB 4706.1-1998 are applicable. 24 Components
The contents of this chapter in GB 4706.1-1998 are applicable except for the following contents. 24. 1 This clause adds the following contents;
The switch shall cut off all poles, and the contact of each pole shall have an opening distance of at least 3mm. The switch shall be able to withstand 10 000 operation tests. 25 Electrical connection and external flexible cord
This chapter in GB4706.1-1998 is applicable except for the following contents. 25.1 This article adds the following contents:
The appliance inlet socket should not allow the connection parts that comply with GB17465.1 to be inserted. 25.7 This article makes the following modifications:
The first paragraph is replaced by the following contents: The power cord should be no lighter than:
-Rubber insulated, ordinary rubber sheathed flexible cord GB5013.4 (code 245IEC53)-PVC insulated, ordinary polyvinyl chloride sheathed flexible cord GB5023.5 (code 227IEC53). 26 External fleece conductor terminals
GB 4706.1-1998 27 Grounding measures
The contents of this chapter in GB 4706.1-1998 are applicable. 28 Screws and connections
The contents of this chapter in GB 4706.1-1998 are applicable. 29 Electrical distances, electrical transmission and penetration distances
The contents of this chapter in GB 4706.1-1998 are applicable. -(2)
GB 4706. 542002/IEC 60335-2-91:1997 Resistance to heat, flame and electrical decay
The contents of this chapter in GB 4706.1-1998 are applicable. 31 Rust prevention
The contents of this chapter in GB 4706.1-1998 are applicable. 32
Radiation, toxicity and similar hazards
GB The contents of this chapter in 4706.1-1998 are applicable.2) mm (see Figure 104). During the test, other parts of the appliance may be protected, if necessary, to prevent impact. After the test, the appliance need not be operational. If the appliance is operational, the following test is immediately carried out, the appliance is operated at maximum speed for 30 seconds with and without cutting elements. If the appliance is not operational and there is no obvious damage to the cutting head, all parts of the user-replaced and removable cutting head are installed on a new appliance, and the new appliance is then operated at maximum speed for 30 seconds with and without cutting elements. There should be no parts falling off and no visible cracks. GB 4706.54—2002/IEC 60335-2-91:199722 Structure
This clause in GB4706.1—1998 is applicable except as follows. 22.36 This item adds the following content:
Hand-held lawn mowers and lawn edge trimmers shall have at least one handle. All hand-held lawn mowers and hand-held lawn edgers with a mass greater than 3.5 kg shall have two handles and the distance between the centres of the handles shall be at least 250 mm.
Note 1: This 250 mm distance measurement does not apply to lawn mowers and lawn edgers with a mass less than or equal to 3.5 kg. In addition, all hand-held lawn mowers and lawn edgers with a mass greater than 6 kg shall have at least one shoulder strap. The weight of the appliance shall be taken when it is in normal use at its heaviest condition and without the power cord. This part of GB 4706 requires that the gripping surface of all handles shall be at least 100 mm long. Note 2: If the size of the part containing the motor reaches 100 mm, it can be regarded as a handle. The gripping length of a ring or closed ring handle shall include all straight sections or the length of the radius of curvature greater than 100 mm, and all bends at the ends (or one of the ends) of the gripping surface with a length not exceeding 10 mm. If the straight handle is centrally supported (e.g. T-shaped), the grip length shall be calculated as follows: a) For handles with a circumference of less than 80 mm (excluding the support), the grip length shall be the sum of the lengths of the two parts excluding the support,
b) For handles with a circumference of 80 mm or more (excluding the support), the grip length shall be the total length from one end to the other. The appropriate part of the handle containing the control actuator of the cutting device shall be considered as part of the grip length of the handle. Finger grips or similar overlapping shapes shall not affect the calculation method of the grip length of the handle. Verified by observation and measurement calculation.
22.40 This clause adds the following content:
The appliance shall be provided with a control and the control shall be required to have two independent and distinct actions before the cutting device is actuated, or the control shall be protected to prevent external operation. Verified by observation, and it shall not be possible to actuate the control by a ball with a diameter of (100 ± 1) mm. The following clauses are added to this chapter:
22.101 The cutting device shall consist of one or more non-metallic cutting elements mounted on or extending from a normal circular cutting head.
Verified by inspection.
22.102 The cutting element shall consist of one of the following components: a) a non-metallic fibre rope; or
b) a non-metallic freely rotating cutter.
For appliances using one or more continuous fibre ropes (wound on a wire attached to the cutting head or other accessory) as cutting elements, a device shall be provided to lengthen the fibre rope and/or automatically limit the rope to the correct operating length after operation of the appliance. Manufacturers shall not supply metallic cutting elements that can replace non-metallic cutting elements. Verified by inspection.
22.103 The kinetic energy of the cutting element shall not exceed 10 J. Verified by inspection, measurement and test. Before testing and measuring, each cutting element shall be stored for at least 7 days at an ambient temperature of (20 ± 3) °C.
For the purpose of this part of GB 4706, kinetic energy is determined by the following formula: Kinetic energy = 1/2mv2(J)
-.....( l)
Where:
GB 4706. 54—2002/1EC 60335-2-91:1997m—mass of the cutting element with a length of L, in kilograms (kg) (see Figure 105):—maximum linear velocity reached at the midpoint Z of a cutting element with a length of L, in meters per second (m/s). Therefore,
V = 0. 104 7n(c-(L/2)
Where:
Maximum speed with a full coil of rope or a new cutter, in revolutions per minute (1/min) r—the distance from the center of rotation of the cutting head to the outside of the cutting device, in meters (m) L—the measured length of the cutting element, in meters (m). Note: The tolerances conform to the requirements of GB/T1804.
23 Internal wiring
The contents of this chapter in GB 4706.1-1998 are applicable. 24 Components
The contents of this chapter in GB 4706.1-1998 are applicable except for the following contents. 24. 1 This clause adds the following contents;
The switch shall cut off all poles, and the contact of each pole shall have an opening distance of at least 3mm. The switch shall be able to withstand 10 000 operation tests. 25 Electrical connection and external flexible cord
This chapter in GB4706.1-1998 is applicable except for the following contents. 25.1 This article adds the following contents:
The appliance inlet socket should not allow the connection parts that comply with GB17465.1 to be inserted. 25.7 This article makes the following modifications:
The first paragraph is replaced by the following contents: The power cord s
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