Hydraulic pump arrangement

Abstract

The invention relates to a portable, battery-operated hydraulic pump arrangement (1) for the drive of a piece of hydraulically operated, portable equipment or rescue equipment (100), the arrangement having a hydraulic fluid circuit comprising: a hydraulic pump (2) for conveying hydraulic fluid in the hydraulic fluid circuit; a control valve (3) for switching the conveying direction of hydraulic fluid in the hydraulic fluid circuit; a hydraulic tank (4) for storing hydraulic fluid in the hydraulic fluid circuit; a compensation function for compensating for a volume change within the hydraulic fluid circuit; and an electric motor (5), preferably a brushless electric motor, having a stator (13), a rotor (14) and an output shaft (6) for driving the hydraulic pump (2). The hydraulic pump arrangement (1) comprises a plate-like holder (9) for attaching the electric motor (5) to the hydraulic pump (2), wherein the electric motor (5) is attached to the hydraulic pump (2) either via an external thread (7) provided on the hydraulic pump (2) and a complementary internal thread (8) provided on the holder (9) or via an external thread (7) provided on the holder (9) and a complementary internal thread (8) provided on the hydraulic pump (2), and wherein the electric motor (5) is attached to the holder (9).

Description

[0001] Hydraulic pump arrangement

[0002] The present invention relates to a hydraulic pump arrangement according to the preamble of claim 1.

[0003] Hydraulically operated, portable work tools or rescue equipment are specialty tools which, unlike battery-operated tools, for example, are only produced in comparatively small quantities for DIY use. At the same time, hydraulically operated, portable work tools or rescue equipment often have special requirements that make it necessary to individually adapt the equipment to their specific application. With regard to the hydraulic pumps used for such equipment, one usually assumes a uniform model type that is specially configured for such devices. Electric motors, on the other hand, are usually purchased parts. However, since the quantities are comparatively small, model changes often occur, especially with regard to the electric motors used, either due to a special supplier situation or possibly due to further motor development.The costs resulting from necessary adjustments to production lines are therefore usually disproportionately high.

[0004] Printed state of the art

[0005] EP 3 434 331 B1 relates to a portable, battery-operated hydraulic pump assembly for driving a hydraulically operated, portable work tool or rescue device with a hydraulic fluid circuit according to the preamble of claim 1. The electric motor is attached directly to the front of the hydraulic pump. JP 2004082273 discloses a hydraulic tool for removing ceiling mounting frames, in which the motor is connected to a hydraulic pump via a gear.

[0006] DE 692 21 221 T2 shows an autonomous multi-purpose tool with a hydraulic drive, in which a pot-shaped housing section defining the tank is screwed via an external thread to a complementary internal thread on the pump housing. In addition to defining the tank volume, the housing section also forms a cavity for accommodating an electric motor.

[0007] EP 3 638 378 B1 discloses a portable, battery-operated hydraulic unit for hydraulic rescue tools, in which a disc rotor motor is attached directly to the housing of a hydraulic tank, so that the hydraulic tank is located between the disc rotor motor and the hydraulic pump.

[0008] Object of the present invention

[0009] The object of the present invention is to simplify the construction of a generic hydraulic pump arrangement.

[0010] Solution to the task

[0011] The above object is achieved by the features of claim 1. Advantageous embodiments of the invention are claimed in the dependent claims.

[0012] According to the invention, a disc- or plate-shaped holder is provided for fastening the electric motor to the hydraulic pump, wherein the electric motor is fastened to the hydraulic pump either via an external thread provided on the hydraulic pump and a complementary internal thread provided on the holder, or via an external thread provided on the holder and a complementary internal thread provided on the hydraulic pump, and wherein the electric motor is fastened to the holder. The holder can thus be fastened to the housing of the hydraulic pump via the internal thread or external thread. This makes it possible to create a standardized hydraulic pump / holder arrangement using a simple molded part. This makes it possible to attach different designs of electric motors to the hydraulic pump without any adaptations to the hydraulic pump or its housing.As a result, a production line is only slightly affected, so that the costs required for an engine change can be kept comparatively low.

[0013] The length of the holding part relative to the longitudinal extent of the drive shaft is smaller than its diameter.

[0014] According to one embodiment of the invention, the holder can project beyond the adjacent hydraulic pump housing when mounted, viewed in the radial direction. This results in the advantage that fastening means can be positioned on this projecting part of the holder.

[0015] According to one embodiment of the invention, a protective cage surrounding or enclosing the electric motor can be attached to the end face of the holder facing away from the hydraulic pump. The protective cage can preferably be attached via fastening means, e.g., first fastening screws, in the part of the holder projecting beyond the adjacent housing of the hydraulic pump, preferably from the side associated with the hydraulic pump. The protective cage can preferably be a molded plastic part.

[0016] According to one embodiment of the invention, the holding part and the electric motor can be screwed together. For this purpose, first fastening screws can engage the stator of the electric motor from the end face of the holder opposite the hydraulic pump. This allows the electric motor to be easily pre-assembled on the holder to form a jointly manageable assembly.

[0017] According to one embodiment of the invention, the output shaft of the electric motor can extend through the retaining part and into the housing of the hydraulic pump. This allows the hydraulic pump-side end of the output shaft to be directly coupled to a drive device of the pump piston, e.g., a swash plate.

[0018] According to one embodiment of the invention, the hydraulic tank can have a flexible tank housing (e.g., made of rubber), whereby the compensating function is determined by the flexibility of the flexible tank housing. The hydraulic tank here ensures a dual function: on the one hand, storing a sufficient amount of hydraulic fluid, and on the other hand, the compensating function for compensating for volume changes within the hydraulic fluid circuit.

[0019] For optimal performance, the hydraulic tank or its flexible tank housing can be bonded to the hydraulic pump housing using a bead of adhesive. This eliminates the need for additional fastening elements, allowing for a particularly space-saving arrangement.

[0020] According to one embodiment of the invention, the adhesive bead can extend partially between the end face of the hydraulic pump housing facing the electric motor and the holder. This enables easier demolding of the flexible tank housing during the manufacturing process.

[0021] According to one embodiment of the invention, the housing of the hydraulic pump can have a front-end housing projection. Sealing means (e.g., a so-called shaft seal) can preferably be accommodated in the front-end housing projection, which seals the hydraulic pump and the output shaft of the electric motor from each other.

[0022] According to one embodiment of the invention, at least one support device, in particular a web-shaped support device, can be provided on the housing and / or the holder, so that when a mechanical force is applied to the housing of the work tool or rescue tool during a work process, the housing of the work tool or rescue tool is supported on the holder. This avoids supporting the housing on the stator of the electric motor, thus allowing a greater degree of freedom with regard to selecting or replacing the electric motor to be used.

[0023] The present invention also relates to a working device or rescue device according to the preamble of claim 13, which comprises a hydraulic pump arrangement according to claims 1 to 12.

[0024] Description of the invention using an embodiment

[0025] A practical embodiment of the present invention is explained in more detail below with reference to the drawing figures. For the sake of clarity, recurring technical features are provided with a reference numeral only once. They show:

[0026] Fig. 1 shows an example of a working device or rescue device with a hydraulic pump arrangement according to an example of the present invention in a longitudinal sectional view;

[0027] Fig. 2 shows the area of ​​the hydraulic pump arrangement from Fig. 1 in an enlarged longitudinal section;

[0028] Fig. 3 shows the hydraulic tank and the housing of the hydraulic pump in a separate, perspective view; Fig. 4 shows the housing of the hydraulic pump and the hydraulic tank attached to it according to Fig. 3 in a perspective view;

[0029] Fig. 5 Components of the hydraulic pump arrangement of the embodiment according to Fig. 1 in an exploded view; and

[0030] Fig. 6 is a perspective partial sectional view of the hydraulic pump arrangement according to the embodiment of Fig. 1 including the housing.

[0031] Fig. 1 shows a work tool or rescue device 100 with an exemplary embodiment of a portable, battery-operated hydraulic pump assembly according to the invention as part of the same. The latter is housed in a housing 101 of the work tool or rescue device 100. The work tool or rescue device 100 further comprises a hydraulic cylinder 103 with a reciprocating piston rod 104 located therein, which serves to drive a multi-part tool located on the tool head in the form of two tool halves 106 (only one of which is shown in Fig. 1). Located in the front area of ​​the valve block 29 is a hollow mandrel 32 for pumping hydraulic fluid into the cavity of the hydraulic cylinder 103.The translational movement of the piston rod 104 is converted into a pivoting movement of the tool halves 106 via pivot arms 112, which are pivotally connected to both the end of the piston rod 104 and the tool halves 106. The tool halves 106 pivot about a central pin 105. The working tool or rescue tool 100 can thus be used for cutting and / or spreading as required. Instead of pivoting tool halves at the front end of the piston rod 104, only a single-piece tool in the form of a rigid tool attachment can be located there. In this case, it is a so-called rescue cylinder.

[0032] The movement of the piston rod 104 within the hydraulic cylinder 103 is achieved by means of a pressurized hydraulic fluid located in a hydraulic fluid circuit and pressurized by a hydraulic pump 2. In the example shown, the hydraulic pump 2 is an axial piston pump and is driven by an output shaft 6 of an electric motor 5. The latter is preferably a brushless DC motor. To drive the hydraulic pump 2, the output shaft 6 is connected to a swash plate 22 of the hydraulic pump 2. When rotated, the swash plate 22 applies an axial compressive force to individual pump pistons 23. Within the hydraulic pump 2, several pump pistons 23 are arranged along a circular circumference. The axial length of the electric motor 5, running parallel to the longitudinal axis of the drive shaft of the electric motor 5, is longer than its outer diameter.

[0033] On a first handle 102 of the housing 101 there is an actuating element 111, e.g. in the form of a star grip, for manually actuating a control valve 3. The control valve 3 serves to control the operation of the work device or rescue device 100 by retracting or extending the piston rod 104 of the hydraulic cylinder 103 or by operating the hydraulic pump arrangement 1 in an idle mode. By actuating the actuating element 111, an operator can select a corresponding operating state, for example from the idle position in a first direction (e.g. for retracting the piston rod 104) or in a second direction (e.g. for extending the piston rod 104). The control valve 3 is a so-called multi-way valve (e.g. a 3-way valve).

[0034] In the area of ​​the actuating element 111 there is a dashboard 109 which can contain an on / off switch and several displays (e.g. a charge level indicator, an operating status indicator or the like). Also located within the housing 101 is the mainboard 107 (motherboard), on which the control components of the electric motor 5 are located. Directly adjacent to the mainboard 107 is the battery compartment 108, into which a rechargeable battery can be inserted. For the sake of clarity, the battery is not shown in Fig. 1. Arranged on the side of the hydraulic pump 2 is the hydraulic tank 4, which can be a hydraulic tank 4 with a flexible tank housing 18. The flexible tank housing 18 is preferably made of rubber and thus enables compensation for volume changes within the hydraulic fluid circuit that occur due to the movement of the piston rod 104 in the hydraulic cylinder 103.The hydraulic tank 4 thus ensures not only its storage function for hydraulic fluid but also a balancing function.

[0035] On the end face of the hydraulic pump 2 facing the electric motor 5, a plate-shaped holder 9 is screwed onto the housing 19 of the hydraulic pump 2, which serves to secure the electric motor 5. The hydraulic pump 2, the holder 9, and the electric motor 5 thus form a sandwich-like arrangement. The hydraulic pump 2 is connected to a valve block 29, which contains hydraulic lines that open into the hydraulic cylinder 103. In the area of ​​the interface between the hydraulic cylinder 103 and the valve block 29, the hydraulic cylinder 103 overlaps the latter on the outside. A second handle 110 is also provided on the hydraulic cylinder 103, so that an operator can operate the work tool or rescue tool 100 with both hands using the first handle 102 and the second handle 110.

[0036] The hydraulic tank 4 is glued to the housing 19 of the hydraulic pump 2. For this purpose, as can be seen from the enlarged illustration in Fig. 2, an adhesive bead 17 is provided that runs along the contact area between the tank and the housing 19 of the hydraulic pump 2 and also extends partially into the space between the housing 19 and the holder 9.

[0037] As can be seen from Fig. 3, a circumferential groove 25 is provided on the pump housing 19 as a reservoir for the adhesive bead 17. A corresponding circumferential projection 27 is provided on the tank housing 18, resulting in a defined, circumferential adhesive geometry for the adhesive bead 17. To establish a fluid connection between the hydraulic tank 4 and the interior of the hydraulic pump 2, through-openings 24 are provided in the housing 19 of the hydraulic pump 2. The hydraulic tank 4 has a recess 30 that allows the holder 9, the electric motor 5, and the protective cage 12 surrounding the electric motor 5 to extend into the recess 30. Furthermore, the housing 19 of the hydraulic pump 2 has mounting openings 26 for attaching the hydraulic pump 2 to the valve block 29.

[0038] Fig. 4 shows the housing 9 of the hydraulic pump 2 and the tank housing 18 of the hydraulic tank 4 glued together. Installation can be carried out in this arrangement. As is clear from Fig. 4, the housing projection 10 with its external thread 7 projects beyond both the housing 19 of the hydraulic pump 2 and the adjacent area of ​​the tank housing 18 of the hydraulic tank 4 in the direction of the electric motor 5.

[0039] Fig. 5 shows the components of the hydraulic pump assembly 1 according to the invention in an exploded view. The plate-shaped holder 9 has an internal thread 8, which corresponds to the external thread 7 on the housing 19 of the hydraulic pump 2, so that the holder 9 can be screwed onto the housing 19 of the hydraulic pump 2. At the same time, the holder 9 serves to fasten the electric motor 5. For this purpose, first fastening screws 15 are provided, which are screwed from the side of the hydraulic pump through the holder 9 into the stator 13 and thus fix the holder 9 to the stator 13 of the electric motor 5. The holder 9 is preferably made of a metal part, e.g., a molded aluminum part.

[0040] Viewed in the radial direction, the holder 9, in the assembled state, projects beyond the housing 19 of the hydraulic pump 2 adjacent to the holder 9, as can also be seen in Fig. 2. This results in the advantage that fastening means in the form of second fastening screws 16 can be arranged in this projecting part of the holder 9, which serve to connect the holder 9 to the protective cage 12 for the electric motor 5. The protective cage 12 surrounds the electric motor 5 or its rotor 14 at a slight distance and thus protects it from damage. It is preferably made of a molded plastic part.

[0041] According to the invention, the protective cage 12 is thus not attached directly to the stator 13 of the electric motor 5, but rather to the holder 9. For this purpose, receptacles 33 for the second fastening screws 16 are provided in the protective cage 12.

[0042] The holder 9 has a web-shaped support device 21 over part of its outer circumference, which serves to provide support for the housing (not shown in Fig. 5) in the event of a mechanical impairment of the working device or rescue device 100 and thereby prevent the housing 101 from pressing on the protective cage 12 or the electric motor 5. Mechanical impairment of the housing 101 can occur, for example, during cutting, when increasing torsional forces act on the cutting tool halves with increasing cutting force, which are transmitted to the housing.

[0043] Fig. 6 shows how the housing 101 of the working device or rescue device 100 is supported on the web-shaped support device 21 of the holder 9. For this purpose, a support device 28 in the form of an inwardly projecting housing web with a curved inner surface is provided on the inside of the housing 101, which rests against the outer contour of the web-shaped support device 21 of the holder 9.

[0044] The present invention enables the installation of differently designed electric motors with a simplified design and reduced costs. REFERENCE SYMBOL LIST

[0045] 1 Hydraulic pump arrangement

[0046] 2 hydraulic pumps

[0047] 3 Control valve

[0048] 4 Hydraulic tank

[0049] 5 Electric motor

[0050] 6 Output shaft

[0051] 7 external threads

[0052] 8 internal threads

[0053] 9 holders

[0054] 10 Housing projection

[0055] 11 Engine housing

[0056] 12 Protective cage

[0057] 13 Stator

[0058] 14 Rotor

[0059] 15 first fastening screw

[0060] 16 second fastening screw

[0061] 17 adhesive bead

[0062] 18 tank housings

[0063] 19 Hydraulic pump housing

[0064] 20 shaft seal

[0065] 21 Support device on the holder

[0066] 22 Swashplate

[0067] 23 pump pistons

[0068] 24 passage opening

[0069] 25 circumferential groove for adhesive bead on pump housing

[0070] 26 Mounting opening

[0071] 27 circumferential projection on tank housing

[0072] 28 Support device on the housing

[0073] 29 Valve block

[0074] 30 Deepening

[0075] 31 third fastening screw

[0076] 32 hollow mandrel

[0077] 33 recording

[0078] 100 rescue equipment

[0079] 101 housings

[0080] 102 first step

[0081] 103 hydraulic cylinders

[0082] 104 Piston rod

[0083] 105 central bolts

[0084] 106 tool half

[0085] 107 Mainboard 108 Battery compartment

[0086] 109 Dashboard

[0087] 110 second handle

[0088] 111 Actuating element 112 Swivel arms

Claims

PATE NTAN SPRÜ CH E 1. A portable, battery-operated hydraulic pump assembly (1) for driving a hydraulically operated portable work tool or rescue tool (100) with a hydraulic fluid circuit, comprising a hydraulic pump (2) for conveying hydraulic fluid in the hydraulic fluid circuit, a control valve (3) for switching the conveying direction of hydraulic fluid in the hydraulic fluid circuit, a hydraulic tank (4) for storing hydraulic fluid in the hydraulic fluid circuit, a compensation function for compensating for a volume change within the hydraulic fluid circuit, an electric motor (5), preferably a brushless electric motor, with a stator (13), a rotor (14) and an output shaft (6) for driving the hydraulic pump (2), characterized by a plate-shaped holder (9) for fastening the electric motor (5) to the hydraulic pump (2),wherein the electric motor (5) is attached to the hydraulic pump (2) either via an external thread (7) provided on the hydraulic pump (2) and a complementary internal thread (8) provided on the holder (9) or via an external thread (7) provided on the holder (9) and a complementary internal thread (8) provided on the hydraulic pump (2), and wherein the electric motor (5) is attached to the holder (9), 2. Hydraulic pump arrangement according to claim 1, characterized in that, viewed in the radial direction in the assembled state, the holder (9) projects beyond the housing (19) of the hydraulic pump (2) adjacent to the holder (9).

3. Hydraulic pump arrangement according to claim 1 or 2, characterized in that a protective cage (12) surrounding the electric motor (5) is fastened to the end face of the holder (9) facing away from the hydraulic pump (2).

4. Hydraulic pump arrangement according to one of the preceding claims, characterized in that the holding part (9) and the electric motor (5) are screwed together.

5. Hydraulic pump arrangement according to claim 4, characterized in that first fastening screws (15) engage in the stator (13) of the electric motor (5) starting from the end face of the holder (9) opposite the hydraulic pump (2).

6. Hydraulic pump arrangement according to one of the preceding claims, characterized in that the output shaft (6) of the electric motor (5) passes through the holding part (9) and dips into the housing (19) of the hydraulic pump (2).

7. Hydraulic pump arrangement according to one of the preceding claims, characterized in that the hydraulic tank (4) has a flexible tank housing (18), wherein the compensating function is determined by the flexibility of the flexible tank housing (18).

8. Hydraulic pump arrangement according to one of the preceding claims, characterized in that the hydraulic tank (4) is glued to the housing (19) of the hydraulic pump (2) via an adhesive bead (17).

9. Hydraulic pump arrangement according to claim 8, characterized in that the adhesive bead (17) runs partly between the end face of the housing (19) of the hydraulic pump (2) facing the electric motor (5) and the holder (9).

10. Hydraulic pump arrangement according to one of the preceding claims, characterized in that the housing (19) of the hydraulic pump (2) has a front-side housing projection (10).

11. Hydraulic pump arrangement according to claim 10, characterized in that sealing means are accommodated in the end-face housing projection (10).

12. Hydraulic pump arrangement according to one of the preceding claims, characterized in that at least one in particular web-shaped support device (21 or 28) is provided on the housing (101) and / or on the holder (9), whereby the housing (101) of the working device or rescue device (100) is supported on the holder (9) when mechanical force is applied to the housing (101) of the working device or rescue device (100).

13. Working device or rescue device (100) comprising a hydraulic cylinder (103), a piston rod (104) movable back and forth in the hydraulic cylinder, and a one-part or multi-part tool, characterized by a hydraulic pump arrangement (1) according to one of the preceding claims.

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