UL 60745-2-13-2011 pdf download

UL 60745-2-13-2011 pdf download.Hand-Held Motor-Operated Electric Tools – Safety- Part 2-13: Particular Requirements for Chain Saws.
19.107,1 The chain brake shall stop the saw chain with an average braking time not exceeding 0,12 S and a maximum braking time not exceeding 0,15 s.
Compliance is checked by the following test.
The chain saw and chain tension shall be ad)usted as for normal use, following the manufacturer’s instruction. The chain tension shall generally be acl,usfed so that, when a 1 kg mass is hanging from the centre of the cutting length along the lower portion of the chain, the gap between the chain side link and the guide bar is a minimum of 0017mm per millimetre of guide bar length.
With the saw chain lubricated as in normal use and operated at rated voltage, the brake actuator is set in
motion by the impact of a pendulum. This pendulum shall have a mass of 0,70 kg, a hammer with a flat strike face 0150 mm diameter and an arm of 700 mm length. The release height of the pendulum shall be 200 mm. The lime for the saw chain to stop shall be measured from the moment of impact with the actuator (see Figure 106).
The chain brake shall be operated a total of 25 times. The maximum stopping time and the average stopptng time of the saw chain shall be measured at the first five and the last five braking operations.
The chain saw is considered to be stopped when the time taken for two successive teeth to pass a fixed point exceeds 10 ins.
The interval between each operation shall be 2 mm consisting of a no-load running penod of I mm prior to each impact of the pendulum. Immediately after the operation of the chain brake and the chain has stopped, the chain saw shall be switched off for the remaining time of the interval. The chain brake actuation mechanism shall be reset during this off period.
19.107,2 The chain brake lever shall be designed so that the static release force required is not more than 60 N and not less than 20 N.
Compliance is checked by the following test.
With the chain saw not running, the force on the chain brake lever needed to activate the brake shall be
measured at the centre of the top (horizontal) part of the chain brake lever and in the direction of 45°
forward and downward in relation to the guide bar centr&ine. see Figure 107.
The force shall be applied at a uniform rate.
19.108 Kickback protectIon
Chain saws shall either be equipped with a bar lip guard which is not removable such as riveted, spot welded, etc. or a computed kickbaci angle or chain stop angle, whichever is less, shall not exceed 45°.
The bar tip guard, it any, shall protect the periphery and both sides of the saw chain at the tip ot the guide bar. The bar tip guard shall be designed to prevent contact of any part of the saw chain with the workpieco within the angle a between the longitudinal aicis of the guide bar and the surface of Ihe workpiece between 45° and 135°, see Figure 108.
Compliance is checked by inspection, measurement and in accordance with the kickback requirements of ISO 9518.
19.110 Saw chain tension
Chain saws shall be provided with means of tensioning the saw chain.
Coinpiance is checked by inspection.
19.111 Saw chain lubrication
The chain saw shall be provided with an oiler for the saw chain.
If the chain saw is fitted with a manual oiler, it shall be so located that it can be operated while holding the saw In both hands In a normal operating position.
Compliance is checked by inspechon.
19.112 Balance
Chain saws shall be in longitudinal balance.
Compliance is checked by the following lest in accordance with ISO 8334.
The chain saw shall be fitted with a supply cord 1 000 mm in length with a plug as provided by the manufacturer and guide bar and chain with the dimensions recommended by the manufaclarer. The oil tank shall be hail full. The spiked bumper shall be fitted.
The chain saw shall be suspended from the front handle gripping area W’ (see Figure 109) at the point giving the best lateral balance. During the test the supply cord shall hang down without contacting any other surface.
The angle between the centreline of the guide bar and the horizontal plane shall not exceed 31°.