GB2239833A

GB2239833A - Handgrips for handtools

Info

Publication number: GB2239833A
Application number: GB9100552A
Authority: GB
Inventors: Hakan Bergqvist; Hans Himbert; Conny Jansson
Original assignee: Bahco Verktyg AB
Current assignee: SNA Europe Industries AB
Priority date: 1990-01-10
Filing date: 1991-01-10
Publication date: 1991-07-17
Anticipated expiration: 2011-01-10
Also published as: GB2239833B; SE9000081D0; GB9100552D0; NL9100005A; JPH04217474A; SE9000081L; DE4100452A1

Abstract

In electrically-driven handtools e.g. battery-driven handtools, the grip region (4) of the handgrip (1) is enlarged with the aid of one or more grip-enlarging devices (5) so as to obtain a grip size which suits the hand size of the person using the handtool. <IMAGE>

Description

1 Improvements in and relating to Handtools The invention relates to

electrically-driven handtools and especially, but not exclusively, to battery-driven electric handtools, also designated '.'cordless machines". The handtool includes a handgrip, with an adaptable gripsize.

Electrically-driven handtools are available commercially in many different forms. The tools are normally produced and retailed with handgrips of only a single grip size. That also applies to battery-driven handtools, such as electric drills, screwdrivers, and so on. In the case of such battery-driven handtools, a problem is presented by the battery pack to be accommodated in the tool. That pack is relatively heavy and of relatively large volume. The battery pack may be dimensioned and positioned so that a predominant part of the pack will be accommodated in the handgrip, which requires the surrounding handgrip casing to be of large dimensions so that it becomes too large for the average hand size. Instead, a much smaller part of the battery pack may be housed in the handgrip with the major part of the battery pack "hanging" down beneath the handle, which increases the total outer dimensions of the machine but allows selective dimensioning of the handgrip.

Thus, when the major part of the battery pack is housed in the handgrip, the handgrip becomes overdimensioned and too large for the average hand and thus also for all hands which are smaller than the handgrip. That is highly disadvantageous from an ergonomic point of view, especially in those cases when the machine used is a production tool, as is very usual in the case of carpenters, electricians, car mechanics, and so on. That is probably the reason why many m.inufacturers of cordless machines have elected to house a minor part of the battery pack in the handgrip and to allow the remainder of the battery pack to "hang" beneath the handgrip. That enables the dimensions of the handgrip to be chosen on the basis of an average-sized hand, but the handgrip is always manufactured and retailed with one single grip size, namely the grip size of an average-sized hand, with the associated problems for operators or users whose hands are smaller or larger than that which is taken by the manufacturer as an "average sized" hand.

The invention provides a handtool including a handgrip, in combination with at least one grip-enlarging device that is arranged in use to be detachably fastened to a grip region of the handgrip, and that in the fitted position abuts the grip region and has a configuration that is in close agreement with the shape of a hand of an actual size larger than that of the underlying handgrip.

The invention also provides an electrically-driven handtool including a handgrip, wherein the grip size of a grip region of the handgrip is adaptable to the size of the user's hand by at least one grip-enlarging device that is detachably fastened to the handgrip and abuts the grip region, and in the fitted position the gripenlarging device has a configuration which is in close agreement with the shape of a hand of the actual size.

It is possible in accordance with the present invention_ to increase the number of grip sizes for an electricallydriven handtool, especially a battery-driven handtool, with the aid of at least one grip-enlarging device which is detachably fitted over the grip region of the handgrip.

The grip-enlarging device can thus be fitted to the tool j i j 1 1 j handgrip and removed therefrom as required. The size and/or thickness of the device can be varied according to the particular group of users concerned.

The enlarging device is advantageously arranged to be fitted over that part of the handgrip which in normal use rests against the palm of the user's hand. It is also possible, however, to configure a corresponding enlarging device for use in that region of the handgrip against which the user's fingers rest, and the grip-enlarging device is then given a configuration which corresponds to the finger position.

When using an electrically-driven handtool the handgrip of which is configured to receive a grip-enlarging device suited to the user concerned, each user can, in principle, obtain a gripping surface which is fully adapted for that particular person. That is particularly beneficial to professional operators who use such handtools daily in their work.

One form of handtool constructed in accordance with the invention will now be described by way of example only with reference to the accompanying drawings in which:

Figure 1 is a perspective view of an electrically-driven handtool in the form of an electric drill, and of a gripenlarging device detached from the machine; Figure 2 is a side view of the same handtool, showing the grip-enlarging device fitted thereto; and Figure 3 is a sectional view taken on the line III-III in Figure 2, and a similar sectional view of a detached grip-enlarging device.

Referring to the accompanying drawings, one form of electric drill comprises a handgrip 1, a motor casing 2, and an electric switch 3 mounted on the upper end of the handgrip 1.

A central part 4 of the handgrip 1 it the region normally gripped by the operator-user when holding the tool in use. The grip region 4 is preferably configured to conform to the smallest hand size likely to occur in the user group in question. In order to enable the grip region 4 to be adapted to larger hand sizes, there are provided grip-enlarging devices 5 of mutually different grip sizes (only one is shown).

The enlarging device 5 has a substantially U-shaped cross-section, as shown in Figure 3, and when the device is not fitted to the handgrip, the legs 6 and 7 of the device are spaced apart at a distance D that is smaller than the thickness B of the handgrip 1 onto which the enlarging device 5 is to be fitted. The enlarging device 5 is made of a resilient plastics material and, when the device is fitted to the handgrip, the legs 6 and 7 will "snap" firmly around the grip region 4 of the handgrip 1.

An inner surface 8 of the enlarging device 5 (see Figure 1) is suitably configured so that when the device is fitted, that surface will tightly abut the grip region 4 of the handgrip 1. The outer surface 9 of the enlarging device 5 may be smooth, as shown in the drawings, or may have a configuration which fits the palm of the user's hand.

Although a preferred embodiment of the grip enlarging device 5 has been described with reference to the accompanying drawings, it will be understood that different modifications are possible without departing i i from the inventive concept. It was mentioned in the introduction that a grip enlarging device intended to fill the space beneath the fingers of the user is possible. It is also possible to provide a grip enlarging device that completely encircles the grip region 4 of the handgrip. As described above the grip enlarging device 5 is attached to the grip region 4 by resilient snap-over action, but it may be secured with the aid of separate fasteners, such as screws, or in some other way.

Although the grip-enlarging device is intended primarily for electricallydriven handtools, and especially for battery-driven handtools, such grip enlarging devices can also be used with similar tools, irrespective of whether the tools are operated manually, pneumatically, hydraulically or in some other way. The invention is not therefore restricted to electrically-driven handtools, but can also be applied with other types of handtools.

6

Claims

Claims: 1. A handtool including a handgrip, in combination with at least

one grip-enlarging device that is arranged in use to be detachably fastened to a grip region of the handgrip, and that in the fitted position abuts the grip region and has a configuration that is in close agreement with the shape of a hand of an actual size larger than that of the underlying handgrip.
2. A handtool as claimed in claim 1 which is an electrically-driven handtool.
3. An electrically-driven handtool including a handgrip, wherein the grip size of a grip region of the handgrip is adaptable to the size of the user's hand by at least one grip-enlarging device that is detachably fastened to the handgrip and abuts the grip region, and in the fitted position the grip-enlarging device has a configuration which is in close agreement with the shape of a hand of the actual size.
4. A handtool as claimed in claim 2 or claim 3, which is battery-driven.
5. A handtool as claimed in any one of claims 1 to 4, wherein the gripenlarging device is configured for attachment over that region of the handgrip which is intended to rest against the palm of the user's hand.
6. A handtool as claimed in any one of claims 1 to 5, wherein the gripenlarging device has a substantially Ushaped cross-section, wherein the two free legs of the device grip resiliently around the handgrip when the device is fitted.
A handtool as claimed in any one of claims 1 to 6, 1 1 i 1 wherein the grip enlarging device is made of a resilient plastics material.
8. An electrically-driven handtool substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.
9. Apparatus comprising a handtool as claimed in any one of claims 1 to 8 in combination with a plurality of said grip-enlarging devices of different external sizes.
10. A method of adapting a handgrip of a handtool to a particular hand, which comprises detachably fitting over a grip region of the handgrip a single-piece grip-enlarging device having two free legs that co-operate resiliently with the handgrip and a main body that abuts the grip region and has, at least in the fitted position, an external configuration in close agreement with the shape of the particular hand.

Published 1991 at The Patent Office. State House. 66/71 High Holborn. LondunWC I R47P. Further copies may be obtained from Sales Branch. Unit 6, Nine Mile point, Cwmfelinfach, Cross Keys, Newport. NPI 7HZ. Printed by Multiplex techniques lid. St Mary Cray. Kent.

10. A device suitable for use as the said grip-enlarging device of a handtool as claimed in any one of claims 1 to 8.

11. A method of adapting a handgrip of a handtool to a particular hand, which comprises detachably fitting over a grip region of the handgrip a grip-enlarging device that abuts the grip region and has, at least in the fitted position, an external configuration in close agreement with the shape of the particular hand.

2 Amendments to the claims have been filed as follows 1. A handtool including a handgrip, in combination with at least one grip- enlarging device that is a single part arranged in use to be detachably fastened to a grip region of the handgrip by having two free legs that in the fitted position co-operate resiliently with the handgrip, a main body of the device abutting the grip region and having a configuration that is in close agreement with the shape of a hand of an actual size larger than that of the underlying handgrip.

2. A handtool as claimed in claim 1 which is an electrically-driven handtool.

3. An electrically-driven handtool including a handgrip, wherein the grip size of a grip region of the handgrip is adaptable to the size of the user's hand by at least one grip-enlarging device that is detachably fastened to the handgrip by two legs that resiliently co-operate with the handgrip when the device is fitted, and wherein a main body of the device and abuts the grip region, and in the fited position the grip-enlarging device has a configuration which is in close agreement with the shape of a hand of the actual size.

4. A handtool as claimed in claim 2 or claim 3, which is battery-driven.

5. A handtool as claimed in any one of claims 1 to 4, wherein the gripenlarging device has a substantially U-shaped cross-section and is configured for attachment 1 i 1 over that region of the handgrip which is intended to rest against the palm of the user's hand.

6. A handtool as claimed in any one of claims 1 to 5, wherein the grip enlarging device is made of a resilient plastics material.

7. An electrically-driven handtool substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

8. Apparatus comprising a handtool as claimed in any one of claims 1 to 7 in combination with a plurality of said gripenlarging devices of different external sizes.

9. A device suitable for use as the said grip-enlarging device of a handtool as claimed in any one of claims 1 to 7.