WO1996000140A1

WO1996000140A1 - A lever for a power tool

Info

Publication number: WO1996000140A1
Application number: PCT/GB1995/001483
Authority: WO
Inventors: Roger Robert Saunders
Original assignee: Desoutter Ltd
Current assignee: Air Compressors and Tools Ltd
Priority date: 1994-06-27
Filing date: 1995-06-23
Publication date: 1996-01-04
Anticipated expiration: 1996-12-27
Also published as: GB9412858D0; AU2747995A

Abstract

An extendable lever (5) comprises first and second telescopic elongate members (11, 13) which are releasably located in a plurality of predetermined positions relative to each other by engagement of a displaceable latching element (15) with one of a plurality of recesses (17). The extent of relative travel of the members (11, 13) is limited by abutment of a step (23) with a hole (21).

Description

A LEVER FOR A POWER TOOL

The present invention relates to an operating lever for a power tool.

One class of conventional power tools is provided with a lever mechanism for activating the tool. However, in holding the barrel of the tool against the hand rest, some operators have insufficient finger reach to hold the lever in the activated position. Therefore, in order to operate the tool, the operator has to hold the tool awkwardly, which is uncomfortable and may cause the operator' s hand to slip off the lever, deactivating the tool. This is because the lever of such conventional power tools does not suit a wide range of hand sizes.

The present invention provides an extendable lever that enables hands of different size to use the power tool.

In particular, the invention provides an operating lever for a power tool, comprising a first elongate member having an end adapted for pivotal connection to a portion of the power tool, and a second elongate member mounted on the first member, the second member being longitudinally slidable relative to the first member to vary the length of the operating lever.

The lever preferably includes means for releasably locating the first and second members at a plurality of predetermined positions relative to each other. Also, it preferably includes limiting means for limiting the extent of travel of the second member relative to the first member.

Preferably, the first and second members are telescopic and are releasably held in a predetermined position by engagement of a displaceable tooth member, in the form of a spring metal member having a raised portion, into one of a plurality of detents.

The first and second members may be extended by sliding one on top of the other and engaging by a tongue and groove arrangement.

The limiting means may be in the form of a hole which engages the raised portion of the spring metal member and by virtue of a step in the raised portion is prevented from further movement in one direction when engaged with the hole.

A power tool according to the present invention includes an extendable lever for operating a function of the power tool.

The present invention will now be explained in more detail by way of the following description of a preferred embodiment and with reference to the accompanying drawings, in which: -

Figure 1 is aside view of a power tool with an operating lever; and

Figure 2 is a longitudinal cross-section through the operating lever, on an enlarged scale.

The power tool 1 shown in Figure 1 comprises a body or barrel 3 and an extendable operating lever 5. The power tool 1 is illustrated in its position of use, in which it hanges from a line (not shown) for providing motive power to an air motor (or an electric motor) in the tool. The rear (upper) end of the lever 5 is pivotably attached to the rear portion cf the barrel 3 by a pivot 9.

The middle portion of the barrel 3 has a thumb-engaging recess 2, longitudinal r; . 4 which facilitate gripping by the fingers and palm, and a protuberance 7 serving as a hand rest. Between the middle portion and the rear (upper) portion, there is a reversing switch 6 operable by the thumb. The lever 5 is depressed by (at least) the index finger to actuate an on-off switch 8.

With reference to Figure 2, the extendable lever 5 comprises a first, inner, elongate member 11 whose rear end portion is formed with lugs 12 for attaching the lever to the pivot 9 of the barrel 3. The first, inner member 11 is fitted with a second, outer, elongate member or sleeve 13 which slides over the front end of the inner member 11. The longitudinal axis of the sleeve 13 is substantially parallel to the longitudinal axis of the inner member 11. Permanently fixed to the inner surface of the sleeve 13 is a spring metal latching element 15 which extends along the length of the sleeve and has a raised detent portion 14 positioned approximately halfway along the sleeve. The latching element 15 is connected to the sleeve 13 by a rivet 16 and has a protruding portion 19 which locates it in the sleeve.

The inner member 11 includes a plurality of bevelled recesses 17 spaced at intervals along its length and a hole 21 positioned furthest from the pivot end of the member 11.

The middle portion of the barrel 3 of the power tool is held by the operator with the extendable lever 5 facing away from him. The tool is activated by squeezing the lever 5 towards the barrel 3. In order to accommodate different hand sizes, the length of the lever 5 is adjustable by extending it. This is achieved by pulling the sleeve 13 longitudinally to release the raised detent portion 14 of the latching element 15 from one of the recesses 17 and sliding the sleeve 13 until the latching element 15 engages the next recess 17.

The hole 21 prevents removal of the sleeve 13 from the inner member 11. This is due to the extent and degree of penetration of the detent portion 14 of the latching element 15 and the shape of the detent portion 14, which is has a step 23 on the forward side which engages against the abutment surface defined by the hole 21. The rearward side of the detent portion 14 has a shallow slope allowing disengagement of the detent portion 14 from the hole 21 in the rearward direction. Therefore, the extendable lever can be adjusted to suit operators having different hand sizes, thus enabling the lever to be reached to activate the tool while the operator' s hand rests against the hand rest.

Claims

CLAI MS

1. An operating lever for a power tool, comprising a first elongate member having an end adapted for pivotal connection to a portion of the power tool, and a second elongate member mounted on the first member, the second member being longitudinally slidable relative to the first member to vary the length of the operating lever.

2. An operating lever as claimed in claim 1, in which the second member partly covers the first member.

3. An operating lever as claimed in claim 1, further comprising locating means for releasably locating the second member in a plurality of predetermined positions relative to the first member.

4. An operating lever as claimed in claim 3, in which the locating means comprises a releasable latching element carried by one of the said members and a plurality of latch-engaging recesses on the other of the said members.

5. An operating lever as claimed in claim 4, in which the latch-engaging recesses have bevelled edges.

6. An operating lever as claimed in claim 4, in which the latching element is spring loaded.

7. An operating lever as claimed in claim 6, in which the latching element is made of spring metal.

8. An operating lever as claimed in claim 1, further comprising limiting means for limiting the longitudinal sliding of the second member relative to the first member.

9. An operating lever as claimed in claim 8, in which the limiting means comprises a latching element carried by one of the said members and an abutment surface on the other of the said members.

10. A power tool comprising a body and an operating lever, the operating lever comprising a first elongate member having an end pivotally connected to the body and a second elongate member mounted on the first member, the second member being longitudinally slidable relative to the first member to vary the length of the operating lever.