GB2405114A

GB2405114A - Tool receptacle, in particular a quick-change clamping chuck

Info

Publication number: GB2405114A
Application number: GB0416734A
Authority: GB
Inventors: Manfred Karpf; Helmut Wanek; Dietmar Kengeter
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2003-07-30
Filing date: 2004-07-27
Publication date: 2005-02-23
Also published as: CN1583334A; GB0416734D0; DE10334619A1

Abstract

A tool receptacle, in particular a quick-change clamping chuck, particularly for motor-operated hand-held machine tools 10, in particular screwdrivers, drills or the like, has a holding sleeve 21 with a locking arrangement 22 for detachably locking a tool which can be received in said holding sleeve 21. The holding sleeve 21 with the locking arrangement 22 is encompassed, on the outside, by an external protective arrangement 40 which masks their outer faces in a protective manner and which offers protection for the said outer faces as well as for components that come into contact therewith. The tool receptacle 20 is thereby protected against damage, any components that come into contact therewith also being likewise protected against being damaged by said tool receptacle 20.

Description

24051 1 4 - 1 Tool receptacle, in particular a quick-chanqe clamping chuck

Prior art

The starting point of the invention is a tool receptacle, in particular a quick-change clamping chuck, of the kind defined in the precharacterising clause of claim 1.

In the case, in particular, of motor-operated hand-held machine tools, in particular screwdrivers, drills or the like, there is the risk of mechanically contactable parts of the tool receptacle being damaged or destroyed when the hand-held machine tool is in use, in which case the tool receptacle then loses its operability. This is the case, for example, if a spring-ring, which secures a locking bush belonging to a locking arrangement and pretensioned by a spring, is damaged or destroyed. There is also the risk, when the hand-held machine tool is being used in the intended manner, of components that come into contact with the tool receptacle being damaged by said machine tool, and in particular by said tool receptacle. When the hand-held machine tool is designed, for example, as a screwdriver, it serves for connecting or fastening parts to one another by screwing. The parts in question may, particularly if said machine tool is used in vehicle construction, be finish- enamelled body parts in which damage resulting from scratches in the coat of paint when the hand-held machine tool is used is to be avoided.

Advantages of the invention The tool receptacle according to the invention having the features in claim 1 has the advantage that, because of the protective arrangement, the tool receptacle itself is protected against damage and that, furthermore, components that come into contact with said tool receptacle during handling, for example parts that are to be connected to one another, are protected against being damaged by said tool receptacle. The protective arrangement is simple and cost- effective and is easy to fit or remove. It can also be put on afterwards without special accessories or tools being required. In the event of the protective arrangement sustaining any wear, it can simply be replaced, the actual functioning of the tool receptacle being guaranteed, as before, even without the protective arrangement. Said protective arrangement is also suitable as a retrofit component and can be put on afterwards in a simple manner in the case of hand-held machine tools that are already in service.

Advantageous further developments of, and improvements to, the tool receptacle indicated in claim 1 are possible by means of the measures set out in the other claims.

Drawings The invention is described in greater detail below with the aid of an exemplified embodiment which is represented in the drawing. The latter shows a diagrammatic section through a tool receptacle in the form of a quick-change clamping chuck belonging to a motor-operated hand-held machine tool in the form of a screwdriver.

Description of the exemplified embodiment

The drawing shows, diagrammatically, the end of a motor- operated hand-held machine tool 10 which consists, for example, of a screwdriver, a drill or the like and is driven by means of an, in particular, electric driving motor, of which nothing further is shown but which has a gear unit which is connected on the output side of said motor but is likewise not represented. At the end, the hand-held machine tool 10 has an axially directed tool receptacle 20, particularly in the form of a quick-change clamping chuck, which is represented. Said tool receptacle has a holding sleeve 21 with a locking arrangement 22 for detachably locking a tool which can be received in said holding sleeve 21 but of which nothing further is shown.

The tool is received, by its shaft, in an axial inner receptacle 23 in the holding sleeve 21, which receptacle has, for example, a polygonal contour, for example a hexagonal contour, matching a corresponding cross- sectional shape of the shaft of the tool. The locking arrangement 22 has a locking bush 24 which engages over the holding sleeve 21 and is axially displaceable and secured on the latter.

On the left-hand side, in the drawing, of an annular projection 25 which is directed radially inwards, use is made, for securing purposes, of an Oring 26 which is received in an annular groove 27 in the holding sleeve 21 and serves as a stop, which is on the left in the drawing, for said annular projection 25.

In the region of the front end 28 of the holding sleeve 21, there is received, in an annular groove 29 at that point, a spring ring 30 which serves to axially support a spring 31 which is axially supported, by its end which is on the left in the drawing, against that side of the annular projection 25 which faces towards it, and which spring rests, by its opposite end, against a supporting ring 32 which is located on the holding sleeve 21 and is supported by the spring ring 30. The spring 31 acts as a compression spring, the pretensioning of which is guaranteed by the supporting ring 32 and the spring ring 30. The locking bush 24 is continuously held, via the spring 31, in the locking position shown, in which the shaft of a tool, for example a screwing tool, that has been put into the receptacle 23, is axially locked. For locking purposes, use is made of at least one locking body 33 in the form of a radially movable ball which is held in an associated radial bore 34 in the holding sleeve 21 in a captive manner and in such a way that, for the purpose of effecting unlocking by displacement of the locking bush 24 towards the right in the drawing, the at least one locking body 33, which is released radially by the annular projection 25, is able to travel radially outwards and release the tool. In the position represented in the drawing, the locking body 33 is pressed by the annular projection 25 radially in the direction of the centre of rotation of the tool receptacle 20, thereby locking a tool, not shown, which has been mounted in the receptacle 23.

The spring ring 30 located in the region of the front end 28 guarantees the operability of the tool receptacle 20 in the form of the quick-change clamping chuck. Because of its location, the spring ring 30 is susceptible to mechanical loading and, in particular, damage. Should damage occur in this region, the spring ring 30 may be destroyed, as a result of which the tool receptacle 20 loses its entire operability.

The outer faces of the locking bush 24 and those at the free front end of the holding sleeve 21, as well as the spring ring 30, may damage components which come into contact with them. Such a risk of damage exists, for example, in the region of components of this kind which are to be connected to one another by means of the hand-held machine tool 10 in the form of the screwdriver. In vehicle

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construction, for example, said components may be finish- enamelled body parts which are to be connected to one another or to which components are to be fastened, for

example by screws.

In order to provide a remedy in this respect and to, on the one hand, protect the tool receptacle 20 against damage and, on the other hand, protect components which are to be connected with the aid of the handheld machine tool 10 against being damaged by the said tool receptacle 20, provision is made for the holding sleeve 21 with the locking arrangement 22 to be encompassed, on the outside, by a protective arrangement 40 which masks their outer faces in a protective manner and which offers protection, on the one hand, for the said outer faces and, on the other, for components, for example components that are to be connected, which come into contact therewith. This protective arrangement 40 guarantees protection of the mechanical parts of the tool receptacle 20 against damage, and also provides protection of the components that are to be connected by using the hand-held machine tool 10. The protective arrangement 40 is easy to fit and remove. It can be attached afterwards in a simple manner in the case of hand-held machine tools 10 that are already in service.

Should the protective arrangement 40 suffer harm, be damaged or be completely worn out, the actual operability of the tool receptacle 20 nevertheless continues to be completely guaranteed, as before. The protective arrangement 40 can be put onto the tool receptacle 20 by hand in a simple manner without any accessories. The handling of the hand-held machine tool 10 does not change as a result of the protective arrangement 40 which has been put on.

The protective arrangement 40 advantageously consists of a soft, cushioning material, for example rubber, synthetic rubber, plastic or the like. Said protective arrangement - 6 has a wall part 41 which is, in particular, cylindrical and extends axially over essentially at least the entire length of the locking bush 24. The wall part 41 encompasses the locking bush 24 over its entire length, on which said wall part 41 is held in a detachable but displacement-proof and/or torsion-proof manner. This comes about in a simple manner through the fact that the wall part 41 is drawn onto the locking bush 24 and held on the latter in a gripping manner. At the same time, the holding action is further assisted by the fact that said locking bush 24 is provided, in the usual manner, over its outer peripheral face with knurling which, as a roughening of the surface, further increases the static friction between the said surface and the wall part 41 of the protective arrangement 40.

The protective arrangement 40 extends beyond the free front edge 28 of the holding sleeve 21. In this case, it may be sufficient if the, in particular, cylindrical wall part 41 is prolonged axially by a suitable collar, so that the entire protective arrangement 40 consists merely of a cylindrical wall part of this kind with an axial prolongation in the region of the front end 28, the said axial prolongation protruding beyond the end face 35 of the holding sleeve 21 and, in this way, guaranteeing suitable protection against contact, both for the tool receptacle 20 and also for the parts that are to be connected by means of the hand-held machine tool 10.

In the exemplified embodiment shown, the protective arrangement 40 is configured in such a way that it masks the end face 35 of the holding sleeve 21 in a protective manner and rests, with an annular part 42, against the said end 35, thereby covering the latter. In this case, the annular part 42 adjoins, at its end, the wall part 41, with which said annular part 42 is preferably in one piece. In this configuration, the protective arrangement 40 then - 7 consists of an approximately pot-like protective cap 43 whose wall is formed by the wall part 41 and whose base is formed by the annular part 42, the latter containing, in the centre, an admission aperture 44 through which the insertable tool passes.

The protective cap 43 is pushed, starting from the free front end 28 of the holding sleeve 21, onto the locking bush 24 of said holding sleeve and is held thereon in a gripping manner, thereby externally masking said locking bush 24 and the free front end 28 of the holding sleeve 21, including elements, such as the supporting ring 32 and spring ring 30 for example, which are disposed thereon.

It goes without saying that the protective arrangement 40 described can also be put onto the tool receptacle 20 at any time afterwards as an independent component and without the need for accessories, and is thus also suitable, in advantageous manner, as a component for retrofitting to existing hand-held machine tools 10. - 8

Claims

Claims 1. Tool receptacle, in particular a quick-change clamping chuck,

particularly for motor-operated hand-held machine tools (10), in particular screwdrivers, drills or the like, said tool receptacle having a holding sleeve (21) with a locking arrangement (22) for detachably locking a tool which can be received in said holding sleeve (21), characterized in that the holding sleeve (21) with the locking arrangement (22) is encompassed, on the outside, by an external protective arrangement (40) which masks their outer faces in a protective manner and which offers protection for the said outer faces as well as for components that come into contact therewith.
2. Tool receptacle according to claim 1, characterized in that the protective arrangement (40) consists of a soft, cushioning material, for example rubber, synthetic rubber, plastic or the like.
3. Tool receptacle according to claim 1 or 2, characterized in that the protective arrangement (40) has an, in particular, cylindrical wall part (41).
4. Tool receptacle according to claim 3, characterized in that the protective arrangement (40) encompasses, with its, in particular, cylindrical wall part (41), an external locking bush (24) which is axially displaceable and secured on the holding sleeve (21) and on which said wall part (41) is held in a detachable but displacement-proof and/or torsion-proof manner. 9 -
5. Tool receptacle according to one of claims 1 to 4, characterized in that the protective arrangement (40) extends beyond the free front end (28) of the holding sleeve (21).
6. Tool receptacle according to one of claims 1 to 5, characterized in that the protective arrangement (40) masks the end face (35) of the holding sleeve (21) in a protective manner.
7. Tool receptacle according to one of claims 3 to 6, characterized in that the protective arrangement (40) has an annular part (42) which adjoins, at its end, the wall part (41), is in one piece with said wall part (41), covers the free front end (28) of the holding sleeve (21) and rests against the end face (35) of the latter.
8. Tool receptacle according to one of claims 1 to 7, characterized in that the protective arrangement (40) consists of an approximately potlike protective cap (43) whose wall is formed by the wall part (41) and whose base is formed by the annular part (42).
9. Tool receptacle according to claim 8, characterized in that the protective cap (43) is pushed, starting from the free front end (28) of the holding sleeve (21), onto the locking bush (24) of said holding sleeve and is held thereon in a gripping manner, thereby masking said locking bush (24) and the free front end (28) of the holding sleeve (21), including elements, such as, for example, a supporting ring (32) with a spring ring (30) axially supporting the latter, which are disposed thereon. - 10
10. Protective arrangement for a tool receptacle, in particular a quickchange clamping chuck, particularly for motor-operated hand-held machine tools (10), in particular screwdrivers, drills or the like, said tool receptacle having a holding sleeve (21) with a locking arrangement (22) for detachably locking a tool which can be received in said holding sleeve (21), characterized by an approximately pot-like protective cap (43) which consists of a soft, cushioning material, for example rubber, synthetic rubber, plastic or the like, and which can be pushed, starting from the free front end (28) of the holding sleeve (21), onto the locking bush (24) of said holding sleeve and held thereon in a gripping manner, thereby externally masking said locking bush (24) and the free front end (28) of the holding sleeve (21), including elements, such as, for example, a supporting ring (32) with a spring ring (30) axially supporting the latter, which are disposed thereon.
A tool receptacle substantially as herein described with reference to the accompanying drawing.
12. A protective arrangement for a tool receptacle substantially as herein described with reference to the accompanying drawing.