GB2273965A

GB2273965A - Coupling for hand-held machine tools with hose for removing chips

Info

Publication number: GB2273965A
Application number: GB9326283A
Authority: GB
Inventors: Guenter Schaal; Guenther Berger; Mario Frank
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1993-01-02
Filing date: 1993-12-23
Publication date: 1994-07-06
Also published as: ITMI931012V0; ITMI932738A1; DE9300006U1; ITMI932738A0; GB9326283D0; IT1265449B1; ITMI931012U1

Abstract

A hand-held machine tool 1 with an outlet channel 2 in a tubular connection piece 4 intended for removing chips, dust or similar is connected to an extension hose 8 or the like, by a coupling sleeve 9 at the end of the hose 8, providing, using simple means, a positively locking coupling to the hose or tube or the like, which is particularly secure against being unintentionally released. The hose 8 or the like is fastened to the hand-held machine tool 1 by means of a split sleeve 10 which engages around hose 8 in a manner which allows it to be able to expand along the periphery of the hose and, at the front end, can be pushed in an expanding manner onto the hand-held machine tool 1, preferably in a positively locking manner onto the outlet channel 2 thereof. <IMAGE>

Description

Hand-held machine tools with hose for removing chips Prior Art The invention proceeds from a hand-held machine tool according to the generic type of Claim 1.

DE-OS 38 37 492 discloses a releasable quick-action plugin connection between two tubes, in which tubes or hoses can be arranged sealed with respect to each other and secured axially by parts which mutually overlap one over the other concentrically and latch one into the other.

This quick-action plug-in connection can be used in particular in oil and fuel lines for vehicles.

Hose couplings for hand-held machine tools or for vacuum cleaners are also constructed in accordance with this quick-action plug-in connection. In a simple embodiment, these are composed, for example, of tube or hose ends which are shaped conically and can be pushed one into the other. In a more complex embodiment, the tube or hose ends are annularly engaged around by sleeve-like end pieces which are coupled by pushing one into the other.

The axial position thereof can, for example, be secured in a defined manner by virtue of the fact that the sleeves are designed as a collar sleeve and the collar of the overlapping sleeve comes to bear like a stop against a collar of the overlapped sleeve.

Sleeve-type plug-in connections for tubes or hoses have also been disclosed, which, using additional catch-like means, permit a latching connection and hence axial retention in a particularly reliable manner of the parts to be connected.

The tube or hose couplings which are known, which are of simple construction and can be easily produced, have either too low a fastening reliability against being unintentionally released or, in the case of high fastening reliability, require a high production and installation cost.

Advantages of the invention The hand-held machine tool according to the invention and the hose according to the invention and the sleeve according to the invention with the characterizing features of Claim 1 and 8 and 10, respectively, have the hitherto incompatible advantages of simple production, good handling, extremely simple installation and high fastening reliability.

The sleeve according to the invention makes possible a reliable, dust-tight coupling of a hose to a tubular connection piece against unintentional, high release forces, for example in the case of vibrations or shock loadings when operating a drill hammer, a saw or an eccentric grinder. Previously known hose socket systems for non-positive coupling can be used and, by adding the sleeve, can be modified at very low expense to form positive couplings.

Owing to the axial displaceability of the sleeve with respect to the hose or the socket, dimensions of relatively coarse tolerance are possible for the projection on the tubular connection piece without impairing the tightness and reliability of the plug-in connection between hose and tubular connection piece.

Further advantageous developments of the invention emerge from the dependent claims.

Drawing An exemplary embodiment of the invention is explained in more detail in the description below, with reference to the accompanying drawings.

Figure 1 shows part of a hand-held machine tool together with a couplable hose, represented in a pulledapart state, Figure 2 shows the exemplary embodiment according to Figure 1 when plugging together, prior to latching, and Figure 3 shows the exemplary embodiment according to Figure 1, plugged together and latched.

Description of the exemplary embodiment The hand-held machine tool 1 represented in Figure 1 is only represented by its region bearing an outlet channel 2 for removing chips, dust or similar. The wall 3 of the outlet channel 2 forms a tubular connection piece 4 which merges step-like into a smaller, cylindrical diameter region. Arranged on the periphery of the larger diameter region are two ridge prism-shaped projections 5, 6 which lie diametrically opposite each other and of which only one is shown.

Arranged axially flush with respect to the mouth 7 of the outlet channel 2 or the tubular connection piece 4 is a hose 8, the free end of which is annularly and captively engaged around by a socket 9. The hose 8 and the socket 9 are engaged around by a sleeve 10 which bears a slit 11, which is continuous over its entire length, and which projects by a free end 12 over the free front side of the socket 9. The socket 9 engages around the hose 8 in a manner such that it can be displaced axially with little play and can be rotated at least by a small amount. The free end 12, projecting over the socket 9, of the sleeve 10 bears, on the side opposite the continuous slit 11, a cutout 13 which is open at the front end. In addition to the cutout 13, the sleeve bears a first opening 14 and, arranged diametrically with respect to the latter, a second opening 15.In addition, on its periphery the sleeve 9 [ sic ] bears elastic clamping means 16, 17, 18 for non-positively or positively receiving an auxiliary tool 19, for example a wrench for socket head cap screws, with which a fastening screw or the like, of a saw blade (not shown), a grinding wheel or a grinding plate of the hand-held machine tool 1 with external or integrated suction device (not shown), can be released.

The mouth 7 of the tubular connection piece 4 or the smaller, cylindrical diameter region fits flush into the socket 9. The region of the tubular connection piece 4 with the larger diameter fits in a play-free manner into the free end 12 of the sleeve 10. The projections 5, 6 fit between the cutout 13 and the slit 11, respectively, and into the openings 14, 15 of the sleeve 10.

To install the sleeve 10 on the hose 8, the slit 11 is expanded and the sleeve 10 is pushed essentially normally with respect to the axis over the hose 8.

Detachment takes place in the reverse order.

In Figure 2, the same exemplary embodiment as in Figure 1, though rotated about the axis of the hose 7 (sick by 1800 counter to the viewing direction there, is shown in a view from the left looking at the mouth 6 (sic) of the tubular connection piece 4, during the plugging together, prior to latching, of the projections 5, 6 into the openings 14, 15. Here it can be recognised how the projection 6 is positioned between the cutout 13, the sleeve 10 being pushable in the axial direction only slightly further over the tubular connection piece 4 until, at the front end, it strikes axially with cutouts 13 at the front end against the projection 6. The clamping means 16, 17 for the auxiliary tool 19 point here, in the viewing direction, downwards.

In Figure 3, corresponding to the exemplary embodiment of Figure 1, the tubular connection piece 4 with sleeve 10 fastened thereon in a latching manner is shown together with hose 8 and socket 9, the small diameter region of the tubular connection piece 4 being plugged in the socket 9.

Here it is shown how the projection 5 latches into the opening 14 and, by this means, secures the sleeve 10 with respect to the tubular connection piece 4 against being displaced axially. On rotating the sleeve 10 with respect to the tubular connection piece 4, the free end 12 slides over the projections 5, 6 and thus permits intentional releasing by resiliently widening or expanding the free end 12 with respect to the tubular connection piece 4. The clamping means 16, 17 for the auxiliary tool point upwards here. The clamping means 18 is not represented therewith.

From Figures 1 to 3 it can be recognised how the sleeve 10, together with hose 8 and socket 9, is pushed onto the tubular connection piece 4: the sleeve 10 is guided in such a manner over the larger diameter region of the tubular connection piece 4 that the cutout 13 and the slit 11 engage around the projections 5, 6. By this means, the axial end position of the sleeve 10 with respect to the tubular connection piece 4 is achieved.

By subsequently rotating the sleeve 10 with respect to the tubular connection piece 4, the regions of the sleeve 10, which are located between the openings 14, 15 and the slit 11 or the cutout 13, slide onto the projections 5, 6 by the sleeve 10 being expanded in the front region and, as a result, a mechanical resistance being produced.

On further rotation with respect to the projections 5, 6, the openings 14, 15 sink in a latching manner over the projections 5, 6. In this manner, the sleeve 10 is secured axially against being unintentionally released, to the tubular connection piece 4.

To release the sleeve 10, together with the hose 8, from the tubular connection piece 4, the sleeve 10 is rotated with respect to the tubular connection piece 4 counter to the mechanical resistance caused when it expands when sliding onto the projections 5, 6, and is pulled from the-tubular connection piece 4.

In an exemplary embodiment (not shown), of the invention the sleeve, in a design which does not have a stepped cylinder, is directly clamped over the hose in such a manner that a free end of the sleeve projects over the free front end of the hose and can be pushed onto a tubular connection piece of a hand-held machine tool, the front ends of the projections and the corresponding openings of the sleeve being undercut in a barb-like manner at the front end and being resilient.

Owing to the continuous longitudinal slit, the sleeve forms a one-piece clamp on the hose, which clamp, in addition, can slide, at the free front end, without special spring means or further special parts in a resilient manner over a tubular connection piece and secures itself, and thus also the hose, thereon.

Apart from hand-held machine tools, the invention is also suitable for connecting hoses or scaffolding poles to each other.

Claims

1. Hand-held machine tool with an outlet channel (2) which is arranged in particular in a tubular connection piece (4) with a round cross-section, is intended for removing chips, dust or similar and onto which can be pushed, as an extension, a hose (8) or the like, in particular with a coupling sleeve (9) at the end of the hose (8), characterized in that the hose (8) or the like can be fastened to the hand-held machine tool (1) by means of a sleeve (10) which engages around the hose in a manner which allows it to be able to expand along the periphery of the hose and, at the front end, can be pushed in an expanding manner onto the hand-held machine tool (1), preferably in a positively locking manner onto the outlet channel (2) thereof.

2. Hand-held machine tool according to Claim 1, characterized in that the sleeve (10) has at least one longitudinal slit (11), one of which - serving as installation opening for laterally inserting or removing the hose (8) - runs continuously along it and is secured by a part (12), projecting beyond one end of the hose (8), on and/or in the outlet channel (2) - latching onto the wall (3) thereof.

3. Hand-held machine tool according to Claim 2, characterized in that the sleeve (10) is fastened, in its latching position, on and/or in the outlet channel (2) in a manner such that it cannot be displaced axially and, for releasing it, in a manner which allows it to be rotated, in particular resiliently, counter to a mechanical resistance.

4. Hand-held machine tool according to Claim 1, 2 or 3, characterized in that the sleeve (10) and the handheld machine tool (1) bear, in particular at the end of the outlet channel (2), resiliently arranged raised portions (5, 6) and depressions (14, 15), in particular projections and openings corresponding to the contour thereof, which projections and openings serve as latching means, reach one into the other and are secured one on the other.

5. Hand-held machine tool according to one of the preceding claims, characterized in that the sleeve (10) can be secured in a latching manner on the hand-held machine tool (1) by at least one opening (14, 15) and/or by at least one projection (5, 6) on at least one projection (5, 6) and/or opening (14, 15).

6. Hand-held machine tool according to Claim 5, characterized in that the sleeve (10) can be pushed onto and/or into the outlet channel (2) in such a manner that it engages axially with at least one cutout (13), open at the front end, around the projections (5, 6) and, on being rotated about its axis, slides in this position over the projection (5, 6) and, in the process, expands with the result that the opening (14, 15) latches over the projection (5, 6).

7. Hand-held machine tool according to Claim 6, characterized in that in the peripheral direction the projection (5, 6) is bevelled or rounded-off radially with respect to the wall (3) of the outlet channel (2), and in the axial direction, preferably undercut in a barb-like manner, is angular.

8. Hose, for removing chips, dust or similar, of a hand-held machine tool according to the preamble to Claim 1, characterized in that it bears a sleeve (10) which has a continuous longitudinal slit (11) and is used as a coupling means, in a manner such that it can be displaced axially, in particular can be displaced axially in only one direction, and such that it cannot be displaced radially.

9. Hose according to Claim 8, the free end of which opens into a socket (9) which can be pushed, in a nonpositive manner, into or onto a tube or the like, characterized in that the sleeve (10) engages around the socket (9)~

10. Sleeve (10) for the axial coupling of hoses (8), tubes or the like, in particular for a hand-held machine tool according to the preamble to Claim 1, characterized in that it can be fastened, preferably in a positively locking manner, to a hose (8) or to the outlet channel (2) of a hand-held machine tool (1) by being capable of expanding both along its periphery and also at the front end.

11. Sleeve (10) according to Claim 10, characterized in that it is designed as a stepped cylinder corresponding to a stepped cylindrical hose (8) with socket (9) and corresponding to a tubular connection piece (4), which stepped cylinder engages around them and connects them in a coupling manner.

12. Sleeve (10) according to Claim 10 or 11, characterized in that it bears clamping means (16, 17, 18) for receiving an auxiliary tool (19).

13. A hand-held machine tool substantially as herein described with reference to the accompanying drawings.

14. A hose substantially as herein described with reference to the accompanying drawings.

15. A sleeve substantially as herein described with reference to the accompanying drawings.