CN113939660A

CN113939660A - Tool with a locking mechanism

Info

Publication number: CN113939660A
Application number: CN202080041278.7A
Authority: CN
Inventors: D·高普
Original assignee: Baodate Co Ltd And Lianghe Co; Rehau AG and Co
Current assignee: Baodate Co Ltd And Lianghe Co; Ruihao Industrial Europe Co ltd
Priority date: 2019-06-07
Filing date: 2020-06-08
Publication date: 2022-01-14
Also published as: EP3980221A1; DE102019115484A1; WO2020245449A1

Abstract

The invention relates to a tool for a hand-held tool, comprising a cylinder (11) and a piston (6) which is accommodated in the cylinder (11) and is movable in a working direction relative to the cylinder (11), wherein the tool comprises an electrohydraulic drive unit for driving the piston (6) in the working direction, wherein the piston (6) executes a driven movement relative to the cylinder (11) during operation of the tool, and wherein a spring unit (10) which is mounted in the cylinder (11) is provided for restoring the piston (6) counter to the working direction, wherein the piston (6) can be detachably connected to a tool attachment (16, 18) of the tool, such that optionally exactly one tool attachment (16, 18) of a plurality of different tool attachments can be connected to the piston (6). According to the invention, a receptacle (13) is provided outside the cylinder (11), wherein the receptacle (13) is connected to the piston (6) and remains on the cylinder (11) for the tool to be operated with different tool attachments, wherein a quick connection is formed between the receptacle (13) and the tool attachment (16) such that the tool attachment (16) can be mounted on the receptacle (13) without tools.

Description

Tool with a locking mechanism

Technical Field

Hand-held or manually operated tools are known, for example, in connection technology for pressing, for expanding, for bending or for cutting, wherein the tool has a cylinder and a piston which is accommodated in the cylinder and can be moved in a working direction relative to the cylinder for the movement of a tool attachment of the tool. The piston is couplable to the tool attachment.

Background

Such tools comprise, for example, an electrohydraulic drive unit, with which the piston is moved in a working direction in one working step. In operation of the tool, the piston is moved relative to the actuating line, wherein a spring unit is provided which is mounted in the cylinder for a further operating step or for resetting the piston against the operating direction. And is therefore based on the principle of a simple-acting cylinder.

As the piston moves, the tool attachment of the associated tool is removably connected. Preferably, exactly one of a plurality of different tool attachments is optionally connected with the piston by means of the tool, so that the tool attachment moves jointly with the piston.

Disclosure of Invention

The object of the invention is to provide a hand-held tool of the type mentioned above, which is improved in terms of practical use, in particular a tool which is designed to be more compact and which is simple to use flexibly in application with different tool attachments.

This object is achieved by the independent claims. The dependent claims provide advantageous and practical developments of the invention.

The invention is based on a tool for a hand-held tool, in particular a pressing tool, an expansion tool, a bending tool and/or a cutting tool, having a simple-acting cylinder and a piston which is accommodated in the cylinder and is movable in a working direction relative to the cylinder, wherein the tool comprises an electrohydraulic drive unit for driving the piston in the working direction, wherein the piston performs a driven movement relative to the cylinder during operation of the tool, and wherein, for resetting the piston counter to the working direction, a spring unit is provided which is mounted in the cylinder, wherein the piston can be detachably connected to a tool attachment of the tool, such that optionally exactly one tool attachment of a plurality of different tool attachments can be connected to the piston. The active part of the forming tool which acts outwardly on the section to be processed, for example a sanitary line section, is preferably connected indirectly to the piston. The tool attachment may be, for example, a compression yoke, a shifting fork, a cutting attachment, an expanding mandrel, or a bending attachment. Such tools are used, for example, as special tools in sanitary areas. In addition to tool attachments which can be moved with the piston, the tool usually has further tool attachments, wherein at least one section to be machined or at least one element to be machined is positioned between two tool attachments for machining.

The spring unit comprises a preferably compressed spring, in particular a pretensioned compressed spring, for example a helical compressed spring.

The piston comprises a preferably piston element and a piston rod. The piston, or at least the piston element of the piston, which fills the cross section of the cylinder with a first axial side of the piston element and in particular abuts against the hydraulic space of the cylinder in the cylinder, is accommodated hydraulically sealingly on its path of movement on the tool or in the cylinder by means of a sealing arrangement, for example an annular seal, and is guided on the tool or in the cylinder. On the side without hydraulic liquid, the other side of the piston element is preferably connected with a piston rod of the piston, which extends in the interior of the cylinder.

The electro-hydraulic drive unit comprises, for example, a battery-driven hydraulic pump for delivering hydraulic liquid in a reservoir volume to a hydraulic space in a cylinder. The hydraulic space is preferably variable in volume depending on the position of the piston in the cylinder.

One aspect of the invention is that a receptacle is provided outside the cylinder, wherein the receptacle is connected to the piston and the receptacle remains on the cylinder for the tool to be operated with different tool attachments, wherein a quick connection is formed between the receptacle and the tool attachment, so that the tool attachment can be mounted on the receptacle without the need for a tool. The receptacle, which is moved back and forth on the outside on the cylinder and is preferably provided with a sliding layer for this purpose, is part of the tool. The receptacle has an external section and thus an external section of the tool, on which the tool attachment is mounted. The receptacle is preferably a tool element which surrounds the cylinder circumferentially over an axial partial length of the cylinder on the outside, for example a sleeve part which rests on the cylinder side of the cylinder on the outside.

The use of the receptacle which is retained in particular permanently on the cylinder and on the tool and the quick-action connection which is formed on the receptacle and the corresponding tool attachment achieves a better condition with respect to the tools known to date. Since hitherto the tool attachments have each been detachably connected via a detachable connection, for example a plug element, which is engaged, for example, by the piston and the tool holder. This has various disadvantages which are avoided with the present invention. For example, in practice, it is necessary to regularly install or consume unplugged plug elements. The plug element is also often contaminated or damaged during or in the unused state, since it is not blocked on the tool and is therefore not protected. Furthermore, it is cumbersome and time-consuming to remove the plug element each time the tool attachment is replaced, and then to insert a new or next-used tool attachment for it again. The tool attachment change is done with the quick connector in a simple manual operation, for example, a few seconds later.

The quick connection can be designed very compactly and in a loss-proof manner on the receptacle or on the tool attachment, where it is protected against damage, in particular with respect to the outside. Preferably, the quick connection comprises a snap-in assembly with, for example, an elastic snap-in section, which engages elastically with pretension into the snap-in contour, while the connection state is achieved. A releasable locking via the snap-in section ensures a quick connection for the snap-in and is, for example, manually reversible. For example, by manually moving the resilient latching portion from its latching position into the release position. This can be achieved, for example, by a relative movement of the receptacle with respect to the cylinder, wherein a minimum force and/or a minimum moment in the disassembly direction must be applied or overcome.

The quick-action coupling has, for example, a locking element formed by a ball pressure element. The quick coupling preferably also serves as a rotation prevention means for preventing the tool attachment from rotating relative to the cylinder. The quick coupling preferably comprises a resiliently loaded guide pin which engages into and extends along the guide slot up to a position of the guide slot for the guide pin which, when the coupling position is achieved, forms a snap-in position of the guide pin resiliently snapped therein.

The invention also resides in a cylinder having a first axial end side and a second axial end side opposite the first axial end side, wherein the piston comprises a piston element guided against the inside of the cylinder liner, having a first axial side of the piston element adjoining a hydraulic space in the cylinder, which hydraulic space is delimited by the first end side of the cylinder, wherein a spring unit is mounted in a region between the second end side of the cylinder and a section of the piston facing away from the first axial side of the piston element, wherein the section of the piston faces the second axial end side of the cylinder. The spring unit is preferably tensioned between the second end side of the cylinder and the section on the piston rod. A piston or piston element is movable back and forth inside the cylinder, wherein the piston element separates a hydraulic space and a non-hydraulic space in the cylinder from each other. The size of the two spaces or the separation of the hydraulic space and the non-hydraulic space depends on the current position of the piston element in the cylinder.

Preferably, the piston rod protrudes on the second side of the piston element. It is therefore preferred that the spring unit or the compression spring has one end up to the piston rod. The piston rod projects in the working direction or in the direction in which the piston performs the working lift.

The spring unit or helical compression spring is preferably tensioned between the second axial side of the piston element and the second end side of the cylinder. The length dimension of the spring unit or compression spring is related to the position of the piston in the cylinder or the distance of the second axial side of the piston element from the second end side of the cylinder. The length of the compression spring during operation of the tool is determined or compressed to different extents depending on the position of the piston element in the cylinder.

The tool construction length obtained between the tool attachments and the tool size dimension which is important in practice can thereby be reduced, since the spring unit can be reduced to the compressed length or can be compressed to its minimum length.

The cylinder is fixed to the tool or does not move with the drive unit. Simple acting cylinders or hydraulic cylinders are loaded with hydraulic fluid only on the piston side, wherein work is performed in one direction only.

It is also advantageous if the piston has a piston rod which projects on the side of the piston element facing away from the hydraulic space in the direction of the second end side of the cylinder. The piston rod is preferably located in a space in the interior of the cylinder that is not filled with hydraulic liquid. The tool attachment is connected to the piston or its piston rod, for example at an axial location of the piston rod which is at a significant distance from the piston element or in the region of the free end of the piston rod, the piston rod together with the piston element forming the piston.

Advantageously, the spring unit is mounted in the region between the second end side of the cylinder and the end region of the piston rod facing away from the piston element.

The spring unit is preferably supported with one end of the spring unit on an end region of the piston rod and with the other end on the second axial inner end side of the cylinder. The spring unit or the compression spring is mounted in a tensioned or prestressed manner. A restoring force for restoring the piston into the cylinder interior in a direction opposite to the operating direction is thereby always provided. The restoring force acts when the counter force of the hydraulic pressure acting on the first axial side of the piston element is smaller than the spring force acting on the other axial piston side of the reaction.

It is also advantageous if a connecting means for connecting the piston rod and the receptacle is provided, which connecting means passes through the piston rod in the end region of the piston rod facing away from the piston element.

The connection of the piston rod to the receptacle is established, for example, by means of a connecting means, for example a plug element, which engages radially through the piston rod. Preferably, the two ends of the connecting means or the plug element, which extend outside the cylinder, engage in suitable recesses, openings or recesses, respectively, on the receptacle. For this purpose, two opposite openings are provided in the receptacle for the straight, longitudinal connecting means or plug elements. The respective longitudinal end of the plug element, for example the flat end face, is preferably flush with the outside of the receptacle or slightly recessed. In order to pass through and overcome the path of movement of the piston and the receptacle in the direction of reciprocation, the cylinder has two opposing through-openings or openings, for example two long holes, in its cylinder wall, which are elongated in the longitudinal direction of the cylinder. The plug element is, for example, a plug, for example a cylindrical plug.

An advantageous variant is characterized in that the piston and the receptacle are connectable to a connecting device in the form of a plug element, wherein the plug element passes through the cylinder transversely to the working direction and extends as far as into the recess of the receptacle.

The recess is preferably an opening, such as a through hole or a notch.

According to a further advantageous embodiment, the fastening tool attachment can be detachably mounted on the cylinder in the region of the second axial end of the cylinder, wherein the mounted fastening tool attachment is located on the cylinder in a stationary manner during operation of the tool. As a result, during operation, a relative movement occurs between the tool attachment and the fastening tool attachment. The fastening tool attachment is in particular a tool attachment which is fixed in position relative to the cylinder in the axial direction or working direction on the outside of the cylinder in the mounted state during operation of the tool. For the tool function or the work to be performed with the tool, the fastening tool attachment interacts with a tool attachment which is mounted on the receptacle or can be moved on the receptacle. The object to be machined, for example a pipe section, and the mating pin which can be pressed thereon are present between the two tool attachments.

It is also advantageous if the tool attachments are configured as bending tool attachments and/or pressing tool attachments and/or expanding tool attachments and/or cutting tool attachments. In this way, a tool, preferably a combination tool with corresponding tool functions according to the tool attachment variants described above or with at least two combined tool functions is provided which can be used flexibly, wherein the tool base, i.e. the main part of the tool without tool attachment, can be used equally or universally for all variants. Preferably, the different tool attachments each have the same section of the quick-action connection for each tool-free mounting on the receptacle.

Advantageously, the tool attachment is fixable and/or radially fixable on the receptacle via the locking element. Preferably, the tool attachment is fixed on the receptacle radially and axially, preferably rigidly, via at least one locking element. The tool attachment is thereby securely and fixedly secured to the tool during operation of the tool even under load of the tool, thereby providing a tool function with a high degree of reliability. The locking element is, for example, a spring-mounted pin or a cylindrical pin, which projects radially inward on the tool attachment and engages in a suitable recess of the receptacle. The groove extends on the outside in the working direction or longitudinal direction of the cylinder on the receptacle.

According to a variant of the invention, the fastening tool attachment can be detachably mounted on the cylinder via a bayonet connection. The use of a bayonet connection provides a reliable connection, wherein the connection can be reliably established with simple manual operation and can be cancelled again after, for example, a manual release of the fastening process.

Advantageously, the bayonet connection is configured such that the fastening tool attachment can be positioned in exactly one of the positions on the cylinder with respect to the working direction circumference. The fastening tool attachment is thereby attached to the tool or to the outside of the cylinder of the tool in a desired, precise, in particular circumferentially, precisely oriented manner when it has two or more different, respectively individually active tool sections which are offset on the circumference.

It is also considered advantageous that the bayonet connection comprises a snap-in mechanism for snapping the fastening tool attachment onto the cylinder. The connection state can be established reliably and permanently by means of, for example, an audible or perceptible click on the card. The detent mechanism can have, for example, a resiliently mounted detent element and a detent contour which cooperates in a mating manner with the detent element, one end of which is located on the cylinder and the other end of which is located on the fastening tool attachment.

This results in a firmly and reliably designed releasable latching mechanism.

Drawings

Further features and advantages of the invention are described below with reference to some of the schematically illustrated embodiments. In detail in the figures:

figure 1 shows an exploded perspective view from the side obliquely looking into a part of a tool according to the invention,

figure 2 shows a side view of the part of the tool according to figure 1 with a clearly shown inner contour,

FIG. 3 shows a longitudinal section of the part of the tool in the side view according to FIG. 2 assembled and

fig. 4 shows a longitudinal section according to line a-a in fig. 3 of the part of the assembled tool according to fig. 3.

Detailed Description

In the drawing, a tool head 2 of a hand tool according to the invention is shown, which is designed as a pressing tool 1. The entire press tool 1 is illustrated in fig. 3, wherein a schematic contour of a manually operable section 3 of the press tool 1 is shown in dashed lines and broken lines below the specifically illustrated tool head 2.

The tool head 2 may consist of a single tool element. The tool head 2 comprises a hydraulic fluid supply 4 configured as an oil supply, an annular component 5, a piston 6 with a piston element 7 and a piston rod 8, an O-ring 9, a spring unit 10, a hollow cylinder 11, a threaded ring 12, a receptacle 13, a connecting mechanism 14 configured as a plug element 15, a movable tool attachment 16 and a fixed tool attachment 18. The movable tool attachment 16 is designed as a hold-down yoke 17 and the stationary tool attachment 18 is designed as a hold-down yoke 19. Three circumferentially offset fork segments 17a having different fork widths are formed on the press yoke 17. Accordingly, three circumferentially offset fork segments 19a (see fig. 1) each having a different fork width are formed on the press yoke 19.

The cylinder 11 has a first axial end side 11a and a second axial end side 11 b. The piston element 7 has a first axial side 7a which faces a first axial end side 11a of the cylinder 11. The piston 6 has a section 6a facing away from the first axial side 7a of the piston element 7, wherein the section 6a of the piston 6 faces the second axial end side 11b of the cylinder 11.

The annular member 5 comprises two O-rings, two support rings, a groove ring and a locking ring.

The piston element 7 and the piston rod 8 are fixedly screwed to each other.

The schematically shown spring unit 10 is designed as a preferably helical compression spring.

The pressing tool 1 comprises an electrohydraulic drive unit for driving the piston 6 and the pressing yoke 17 in the working direction P1, wherein the drive unit, not shown, is mounted essentially in the manual control section 3.

The piston 6, which is movable relative to the cylinder 11 in the operating direction P1 and, conversely, in the return direction P2, is accommodated in a simple-acting hollow cylinder 11 in a linearly displaceable and guided manner. The cylinder 11 is closed at one axial end, which is received from the outside by the hold-down yoke 19, by a bottom which is formed integrally with the rest of the cylinder 11. The open other end of the cylinder 11 is closed by the hydraulic fluid supply 4.

A spring unit 10, which is also mounted in the cylinder 11, serves to reset the piston 6 in a resetting direction P2.

The piston rod 8 is connected to the receptacle 13 by means of a cylindrical plug element 15. For this purpose, two diametrically opposite, matching holes or round holes 20, 21 are provided in the region of the free end of the piston rod 8, and two opposite holes or round holes 22, 23 filled with the plug element 15 are provided in the receptacle 13. The plug element 15 is also engaged by two opposing through-

openings

24, 25 in the wall of the hollow cylinder 11, wherein the two through-

openings

24, 25 are configured as long holes.

Furthermore, a quick-action connection 26 is formed between the receptacle 13 and the tool attachment 16, so that the tool attachment 16 can be detachably mounted on the receptacle 13 without tools. The quick-action connection 26 has a locking element 27, with which the tool attachment 16 can be fastened to the receptacle 13, preferably in the longitudinal direction or axially of the cylinder 11.

The tool attachment 17 is pushed onto the cylinder 11 and held by a catch, for example.

For example, the tool attachment 17 can likewise be mounted on the cylinder 11 detachably, but firmly, manually via a quick-action connection 28, preferably designed as a bayonet connection 29. The bayonet connector 29 comprises, for example, a snap-in mechanism for snapping the tool attachment 17 onto the cylinder 11. For this purpose, a circumferential annular groove 30 is formed at the end of the cylinder 11, which groove has a flat groove base and a first wall or flank perpendicular to the groove base and an opposing second wall, which has an angle of more than 90 degrees relative to the groove base.

Fig. 3 and 4 show the situation or basic position of the press tool 1 or tool head 2, in which the spring unit 10 mounted in the cylinder 11 moves the piston 6 and the receptacle 13 and the press yoke 17 away from the press yoke 17 in the return direction P2 under the influence of a pretension.

Starting from the basic position of the press tool 1, the hand-held press tool controls the drive unit by manually acting on the manual control section 3 for the working lift or movement of the piston 6 in the working direction P1. The hydraulic fluid stored in the reservoir in the manual actuation section 3 is pumped into the hydraulic line 31 in the hydraulic fluid supply 4 via the opening 33 in the hydraulic fluid supply 4 in the direction P0. The pumping process is carried out in the manual control section 3 by means of a preferably battery-operated hydraulic liquid pump. The hydraulic fluid enters a hydraulic space 32 in the tool head 2 via a hydraulic line 31 between the hydraulic fluid supply 4 and a first axial side of the piston element 7, which is remote from or opposite the axial side of the piston element 7 with the piston rod. The piston element 7, as well as the piston rod 8, the receptacle 13 and the press yoke 17, are moved in the working direction P1 by means of a hydraulic pressure acting in the hydraulic space 32, for example in the case of a continuously pumped hydraulic fluid. Where the length of the spring unit 10 is reduced or more significantly compressed. For example, a pressure connection block (not shown) mounted on the line (not shown) is pressed onto the line under the action of a hydraulically applied force. The respective line section with the pressure connection piece is inserted between two

pressing yokes

17 and 19 spaced apart from each other in advance, on pairs of

respective fork sections

17a and 19a aligned with each other in the pressing longitudinal direction.

For guiding and mounting the pressure connection blocks and lines, corresponding

fork sections

17a and 19a are provided on the press yokes 17 and 19. In order to control line or pressure connections of different diameter sizes, three

different fork sections

17a, 19a matched to the respective line diameter are located in a uniform circumferential offset on the press yokes 17 and 19. Depending on the line diameter, the press yokes 17 and 19 are mounted in the correct circumferential position on the receptacle 13 or on the cylinder 11 in a linearly congruent manner with the associated

fork sections

17a, 19a, which is achieved via the quick-

action connections

26 and 28.

After an operating step, the hydraulic fluid is displaced from the hydraulic space 32 in the direction of the reservoir counter to the direction P0 by actuating the manual control section 3, which is performed under the pressure of the spring element 10 previously tensioned further. The resetting of the press yoke 17 is performed in the direction P2. The pressing tool 1 is remote from the object to be processed.

List of reference numerals

1 pressing tool

2 tool head

3 manual operation section

4 hydraulic fluid supply unit

5 annular member

6 piston

6a segment

7 piston element

Side 7a

8 piston rod

9O-shaped ring

10 spring unit

11 jar

11a, 11b end sides

12 threaded ring

13 accommodating part

14 connecting mechanism

15 plug element

16 tool accessory

17 pressing yoke

17a fork section

18 tool accessory

19 pressing yoke

19a fork section

20. 21 round hole

22. 23 round hole

24. 25 penetration part

26 quick connector

27 locking element

28 quick connector

29 bayonet connector

30 ring groove

31 hydraulic line

32 hydraulic space

33 opening

Claims

1. A tool for a hand-held tool, in particular a pressing tool (1), an expansion tool, a bending tool and/or a cutting tool, having a simple-acting cylinder (11) and a piston (6) which is accommodated in the cylinder (11) and is movable in a working direction relative to the cylinder (11), wherein the tool comprises an electrohydraulic drive unit for driving the piston (6) in the working direction, wherein the piston (6) performs a movement relative to the cylinder (11) during tool operation, and wherein a spring unit (10) which is mounted in the cylinder (11) is provided for resetting the driven piston (6) counter to the working direction, wherein the piston (6) can be detachably connected to a tool attachment (16, 18) of the tool, such that optionally exactly one tool attachment (16, 18) of a plurality of different tool attachments is provided, 18) Can be connected to the piston (6), characterized in that a receptacle (13) is provided outside the cylinder (11), wherein the receptacle (13) is connected to the piston (6) and remains on the cylinder (11) for the tool to be operated with different tool attachments, wherein a quick connection (26) is formed between the receptacle (13) and the tool attachment (16) in such a way that the tool attachment (16) can be mounted on the receptacle (13) without tools.

2. Tool according to the preamble of claim 1, in particular according to claim 1, characterized in that the cylinder (11) has a first axial end side (11a) and a second axial end side (11b) opposite the first axial end side (11a), wherein the piston (6) comprises a piston element (7) guided in abutment on the inside of the cylinder liner, having a first axial side (7a) of the piston element (7) which adjoins a hydraulic space (32) in the cylinder (11) which is defined by the first end side (11a) of the cylinder (11), wherein the spring unit (10) is mounted in a region between the second end side (11b) of the cylinder (11) and a section (6a) of the piston (6) facing away from the first axial side (7a) of the piston element (7), wherein the section (6a) of the piston (6) faces a second axial end side (11b) of the cylinder (11).

3. Tool according to claim 1 or 2, characterized in that the piston (6) has a piston rod (8) which projects in the direction of the second end side of the cylinder (11) on the side of the piston element (7) facing away from the hydraulic space (32).

4. Tool according to any one of the preceding claims, characterized in that the spring unit (10) is mounted in a region between a second end side of the cylinder (11) and an end region of the piston rod (8) facing away from the piston element (7).

5. Tool according to one of the preceding claims, characterized in that a connecting mechanism (14) is provided for connecting the piston rod (8) and the receptacle (13), which connecting mechanism passes through the piston rod (8) in the end region of the piston rod (8) facing away from the piston element (7).

6. Tool according to one of the preceding claims, characterized in that the piston (6) and the receptacle (13) are connectable with a connecting mechanism (14) configured as a plug element (15), wherein the plug element (15) passes through the cylinder (11) transversely to the working direction and extends as far as into a recess (22, 23) of the receptacle (13).

7. Tool according to one of the preceding claims, characterized in that a fastening tool attachment (18) can be detachably mounted on the cylinder (11) in the region of the second axial end side of the cylinder (11), wherein the mounted fastening tool attachment (18) is located on the cylinder (11) in a stationary manner during operation of the tool.

8. Tool according to any one of the preceding claims, characterized in that the tool attachments (16, 18) are configured as bending tool attachments and/or pressing tool attachments and/or expanding tool attachments and/or cutting tool attachments.

9. Tool according to one of the preceding claims, characterized in that the tool attachment (16, 18) is fixable and/or radially fixable on the receptacle (13) via a locking element (27).

10. Tool according to any one of the preceding claims, characterized in that the fastening tool attachment (18) is detachably mountable on the cylinder (11) via a bayonet connection (29).

11. Tool according to any one of the preceding claims, characterized in that the bayonet connection (29) is configured such that the fastening tool attachment (18) can be positioned in exactly one of the positions on the cylinder (11) with respect to the working direction circumference.

12. Tool according to any one of the preceding claims, characterized in that the bayonet connection (29) comprises a snap-in mechanism for snapping the fastening tool attachment (18) on the cylinder (11).