Handheld traction and pressure device and hydraulic actuator

Abstract

The invention relates to a handheld pulling and pushing device and a hydraulic actuator for a handheld pulling and pushing device for driving hydraulic tools, comprising a housing body having a working chamber filled with hydraulic fluid, a hydraulic piston arranged to be displaceable in the working chamber between a starting position and an end position and a hydraulic tool connection with a hydraulic channel connected to the working chamber and having a self-closing valve.In order to provide a hydraulic actuator for an electro-mechanically driven handheld pulling and pushing device, as well as a handheld pulling and pushing device which makes it possible to drive hydraulic tools in addition to electro-mechanically driven pulling and pressing tools, it is provided that the housing body of the hydraulic actuator has a connecting section for the detachable fixing of the hydraulic actuator to a connection section of the pulling and pushing device, and the hydraulic piston has a coupling section for connection with a drive element of the pulling and pushing device that is adjustable relative to the connection section.

Description

[0001] The invention relates to a hand-held pulling and pushing device and a hydraulic actuator for a hand-held pulling and pushing device for driving hydraulic tools, with a housing body having a working chamber filled with hydraulic fluid, a hydraulic piston arranged displaceably in the working chamber between an initial position and an end position, and a hydraulic tool connection with a hydraulic channel connected to the working chamber and having a self-closing valve.

[0002] Handheld pulling and pushing devices are known in a wide variety of designs from the prior art. In some of the known pulling and pushing devices, the pulling and pressing tools that can be connected to the devices are adjusted by means of an electromechanical drive unit. Another group of pulling and pushing devices provides hydraulic pressure to drive pulling and pressing tools designed as hydraulic tools. The hydraulic pressure can be generated, for example, by a compressed air drive, whereby the hydraulic pressure required for operating the hydraulic tools is generated via a pneumatic adjustment of a pneumatic piston and a suitable transmission.

[0003] Due to the hydraulic pressure required for the use of hydraulic tools, it is not possible to combine them with purely electromechanical pulling and pressing devices. This incompatibility makes it necessary to have at least two adapted drive devices available if both electromechanically driven and hydraulically driven tools are required.

[0004] Based on this, the invention is based on the object of providing a hydraulic actuator for an electro-mechanically driven hand-held pulling and pushing device as well as a hand-held pulling and pushing device which makes it possible to drive hydraulic tools in addition to electro-mechanically driven pulling and pressing tools.

[0005] The invention solves the problem by a hydraulic actuator having the features of claim 1 and by a hand-held pulling and pushing device having the features of claim 8. Advantageous developments of the hydraulic actuator are specified in claims 2 to 7.

[0006] The hydraulic actuator according to the invention has a working chamber filled with hydraulic fluid for driving hydraulic tools, i.e. tools for the adjustment of which hydraulic pressure is required. This working chamber is delimited by an inner wall of a housing body and by an end face, facing the working chamber, of a hydraulic piston arranged displaceably in the working chamber between an initial position and an end position. For driving a hydraulic tool, the hydraulic actuator further has a hydraulic tool connection which is connected to the working chamber via a hydraulic channel and closed with a self-closing valve. By an adjusting movement of the hydraulic piston from its initial position towards its end position, a hydraulic pressure is generated by means of which hydraulic tools connected to the hydraulic tool connection can be supplied.

[0007] Characteristic of the hydraulic actuator according to the invention is that the housing body has a connecting section for releasably securing the hydraulic actuator to a connecting section of the pulling and pushing device and the hydraulic piston has a coupling section for connection to a drive element of the pulling and pushing device that is adjustable relative to the connecting section has.

[0008] The design of the housing body with a connecting section allows the hydraulic actuator to be fixed to an electromechanically driven push-pull device, allowing it to be used to drive hydraulic tools. The hydraulic piston is reliably connected via its coupling section to a drive element adjustable via the electromechanical drive, e.g., a tool holder of the push-pull device.

[0009] The fixed arrangement of the hydraulic actuator on the pull-and-push device and the connection of the drive element of the pull-and-push device to the hydraulic piston allow the hydraulic piston to be reliably adjusted between its initial position and its end position. This allows the hydraulic actuator to operate hydraulic tools connected to the hydraulic actuator via the electromechanically acting pull-and-push device. Switching between the connection options for hydraulic tools and electromechanically driven pulling and pressing tools can be easily achieved by disassembling and reassembling the hydraulic actuator.

[0010] The connection of the coupling section of the hydraulic piston to the drive element of the pull-and-push device can basically be made in any way, whereby in the simplest embodiment the drive element rests against the end face of the hydraulic piston facing away from the working chamber. According to an advantageous embodiment of the invention, however, it is provided that the coupling section of the hydraulic piston is designed for a positive connection to the drive element in the adjustment direction of the hydraulic piston. Such a positive connection ensures that the hydraulic piston can be adjusted by the drive element both towards the end position and towards the starting position. The positive connection can be designed for this purpose, for example, in the form of a thread or bayonet lock, so that both tensile and compressive forces of the drive element can be transmitted to the hydraulic piston.

[0011] Essential for the function of the hydraulic actuator is a connection between the hydraulic piston and the drive element of the pulling and pushing device. For this connection, a connecting element can be provided on the hydraulic piston, for example, which can be connected to a drive element within the pulling or pushing device. According to a particularly advantageous embodiment of the invention, however, it is provided that the coupling section of the hydraulic piston is designed for connection to a drive element of the pulling and pushing device, which is designed as a tool holder. The tool holder is usually a component that is arranged in sections on the end face of the pulling and pushing device and is connected to the electromechanical drive, which enables the pulling and pressing tools to be changed easily.The good accessibility required for this makes it particularly easy to connect the hydraulic piston of the hydraulic actuator to the tool holder, for example, by bringing it into contact with the tool holder. It is also possible to connect them in a form-fitting manner so that the hydraulic piston is positively connected to the tool holder in both adjustment directions of the hydraulic piston.

[0012] The connection of the hydraulic actuator to the pulling and pressing device can, in principle, be designed in any desired manner. According to a particularly advantageous embodiment of the invention, however, the connecting section of the hydraulic actuator has a thread or locking body for releasably securing it to the connecting section of the pulling and pressing device, which has a thread or locking body receptacles. A corresponding embodiment of the invention enables a secure and easily releasable connection of the hydraulic actuator to the pulling and pressing device without the need for additional components and / or securing elements. To release the connection between the hydraulic actuator and the pulling and pressing device, it is only necessary to unscrew it from the thread or to release the locking connection.

[0013] The design of the housing body is fundamentally freely selectable. However, according to a particularly advantageous embodiment of the invention, the housing body is made up of multiple parts, in particular two parts. In particular, a two-part design of the housing body allows the hydraulic actuator to be designed such that it consists of a piston housing and a base body. In this design, the base body can be designed and connected to the piston housing in such a way that the base body rests against the hydraulic piston in sections when it is in its initial position, thereby defining the initial position of the hydraulic piston in the housing body. The base body also serves to connect the hydraulic actuator to the push-pull device.A corresponding two-part design of the housing body thus allows not only easy assembly and disassembly on the pull and push device but also easy assembly of the hydraulic actuator and, if necessary, easy maintenance.

[0014] In the simplest embodiment, a displacement of the hydraulic piston from its initial position to its end position can be ensured by simply engaging the drive element on the end face of the hydraulic piston facing away from the working chamber. To ensure that the hydraulic piston can be reset in this case, a particularly advantageous development of the invention provides that the hydraulic piston is preloaded, in particular spring-loaded, toward its initial position. This embodiment of the invention ensures that the hydraulic piston is reliably returned to its initial position without requiring any further modifications to the hydraulic actuator.

[0015] According to a further embodiment of the invention, the hydraulic tool connection is further provided with a quick-release coupling. This enables a simple and convenient change of the hydraulic tools that can be connected to the hydraulic actuator. The self-closing valve reliably ensures that no hydraulic fluid escapes from the hydraulic actuator during a tool change. Furthermore, the hydraulic tool connection, particularly in conjunction with an advantageously provided quick-release coupling, enables the connection to refill or fill the working chamber with hydraulic fluid.

[0016] The invention further solves the problem by a hand-held pulling and pushing device for driving interchangeable pulling and pressing tools with a drive unit having an electric motor, a screw drive with a threaded spindle connected to the drive unit and rotatably mounted on a housing body, and a threaded nut rotatably mounted on the threaded spindle and non-rotatably mounted on the housing body via a bearing unit, and a coupling unit connected to a tool holder, which is connected to the threaded nut in such a way that tensile and compressive forces resulting from the direction of rotation of the threaded spindle are transmitted to the coupling unit, and wherein the tensile and compressive device is detachably connected to a prescribed hydraulic actuator according to the invention or a further developed one.

[0017] The hand-held pulling and pushing device according to the invention enables not only the drive of mechanically driven pulling and pressing tools via the hydraulic actuator but also the drive of hydraulic tools, whereby, if necessary, it is possible to switch between a drive of mechanically driven pulling and pressing tools and hydraulic tools in a simple manner by connecting or disconnecting the hydraulic actuator to the pulling and pushing device.

[0018] An embodiment of the invention is explained below with reference to the drawings. In the drawings: Fig. 1 shows a sectional view of a schematic representation of a hydraulic actuator with a hydraulic piston arranged in an initial position; Fig. 2 shows a sectional view of a schematic representation of a hydraulic actuator with a hydraulic piston arranged in an end position; and Fig. 3 shows a sectional view of a pulling and pushing device with a hydraulic actuator arranged thereon.

[0019] Figure 1 shows in a sectional view an embodiment of a hydraulic actuator 1 with a housing body 2 formed from a base body 4 and a piston housing 3.

[0020] Within the piston housing 3, a hydraulic piston 6 is arranged between a Figure 1 presented initial situation and one in Figure 2The inner surface of the piston housing 3, together with an end face of the hydraulic piston 6, defines a working chamber 5 which is filled with hydraulic fluid. Starting from the position shown in Figure 1 The starting position shown is the hydraulic piston 6, which in this position partially rests against a shoulder 14 of the base body 4 with a front side facing away from the working chamber 5, in the Figure 2 illustrated end position is adjustable, wherein during the adjustment hydraulic fluid arranged in the working chamber 5 can be used via a hydraulic channel 8 to drive a hydraulic tool, not shown here, which can be arranged on a hydraulic tool connection 7.

[0021] To return the hydraulic piston 6 from the Figure 2 shown end position to the Figure 1The initial position shown, in which the hydraulic piston 6 again partially rests against the shoulder 14 of the base body 4, is provided by helical compression springs 11 which are supported at one end on the hydraulic piston 6 and at the other end on an inner surface of the piston housing 3 opposite the hydraulic piston 6 in the direction of adjustment.

[0022] To connect the hydraulic actuator 1 with a Figure 3 In the tension and compression device 25 shown, the base body 4, which is connected to the piston housing 3 via an internal thread 12 and an external thread 13, so that the shoulder 14 rests against an end face 15, has a connecting section 9 which is designed for detachable connection to a connection section 24 of the tension and compression device 25, so that the hydraulic actuator 1 can be arranged stationary on the tension and compression device 25.

[0023] The pull-and-push device 25 has a drive unit 16 with an electric motor 17, by means of which a threaded spindle 20 of a screw drive 19 arranged in a housing body 18 can be driven. In addition to the threaded spindle 20, the screw drive 19 also has a threaded nut 21 arranged on the threaded spindle 20 and mounted in a rotationally fixed manner on the housing body 18. The threaded nut 21 serves to drive a tool holder designed as a piston rod 22, which is adjustably mounted in the longitudinal axis direction of the threaded spindle 20, so that by means of the pull-and-push device 25, the hydraulic piston 6 can be adjusted in the direction of the hydraulic actuator 1 via the piston rod 22 as the drive element. The hydraulic piston 6 has a coupling section 10 on its end face facing the piston rod 22, so that movements of the piston rod 22 are reliably transmitted to the hydraulic piston 6.The piston rod 22 is connected to the threaded nut 21 via a detachably connected coupling unit 23, which rests at its end opposite the piston rod 22 on an end face of the threaded nut 21 facing away from the piston rod 22. List of reference symbols

[0024] 1 Hydraulic actuator 2 Housing body 3 Piston housing 4 Base body 5 Working chamber 6 Hydraulic piston 7 Hydraulic tool connection 8 Hydraulic channel 9 Connecting section 10 Coupling section 11 Helical compression spring 12 Internal thread (base body) 13 External thread (piston housing) 14 Shoulder 15 End face 16 Drive unit 17 Electric motor 18 Housing body 19 Screw drive 20 Threaded spindle 21 Threaded nut 22 Piston rod; tool holder (drive element) 23 Coupling unit 24 Connection section (pull / push device) 25 Pull / push device

Claims

1. Hydraulic actuator for an electromechanically driven pulling and pushing device (25) for driving hydraulic tools, with - a housing body (4) having a working chamber (5) filled with hydraulic fluid, - a hydraulic piston (6) arranged displaceably in the working chamber (5) between a starting position and an end position, and - a hydraulic tool connection (7) with a hydraulic channel (8) connected to the working chamber (5) and having a self-closing valve, characterized in that - the housing body (4) has a connecting section (9) for releasably fixing the hydraulic actuator (1) to a connecting section (24) of the pulling and pushing device (25) and - the hydraulic piston (6) has a coupling section (10) for connection to a drive element (22) of the pulling and pushing device (25) that is adjustable relative to the connecting section (24).

2. Hydraulic actuator according to claim 1, characterized in thatthe coupling section (10) is designed for a positive connection with the drive element (22) in the adjustment direction of the hydraulic piston (6).

3. Hydraulic actuator according to claim 1 or 2, characterized in that the coupling section (10) is designed for connection to a drive element of the pulling and pushing device (25) designed as a tool holder (22).

4. Hydraulic actuator according to one or more of the preceding claims, characterized in that the connecting section (9) has a thread or locking body for releasably securing it to the connecting section (24) of the pulling and pushing device (25) which has a thread or locking body receptacles.

5. Hydraulic actuator according to one or more of the preceding claims, characterized in that the housing body (2) is made up of several parts, in particular two parts.

6. Hydraulic actuator according to one or more of the preceding claims, characterized in thatthe hydraulic piston (6) is preloaded towards the starting position, in particular spring-loaded.

7. Hydraulic actuator according to one or more of the preceding claims, characterized in that the hydraulic tool connection (7) has a quick coupling.

8. A hand-held pulling and pushing device for driving interchangeable pulling and pressing tools, comprising - a drive unit (16) having an electric motor (17), - a screw drive (19) with a threaded spindle (20) connected to the drive unit (16) and rotatably mounted on a housing body (18), and a threaded nut (21) rotatably mounted on the threaded spindle (20) and non-rotatably mounted on the housing body (18) via a bearing unit, and - a coupling unit (23) connected to a tool holder (22) and connected to the threaded nut (22) in such a way that pulling and pushing forces resulting from the direction of rotation of the threaded spindle (20) are transmitted to the coupling unit (23), characterized by a hydraulic actuator (1) according to one or more of claims 1 to 7, which is detachably connected to the pulling and pushing device (25).

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