EP3504433A1

EP3504433A1 - Motor pump device

Info

Publication number: EP3504433A1
Application number: EP17761804.8A
Authority: EP
Inventors: Andreas Böhler; Christian Repplinger
Original assignee: Hydac Fluidtechnik GmbH
Current assignee: Hydac Fluidtechnik GmbH
Priority date: 2016-08-29
Filing date: 2017-08-29
Publication date: 2019-07-03
Anticipated expiration: 2037-08-29
Also published as: EP3504433B1; EP3504433B2; DE102016010669A1; WO2018041401A1

Abstract

A motor pump device designed as a modular system, consisting of at least one electric motor (10), a radial piston pump (24), which can be driven by a respective electric motor (10) and is preferably used as a high-pressure supply, and/or a gear pump (34), which is preferably used as a low-pressure supply, a tank unit (32), add-on parts such as longitudinally-linked valves (48), fill level gauges and terminal boxes, wherein in order to achieve a hydraulic single or multi-circuit system, - each supply pump (24, 34) being used has a dedicated supply connection for the respective circuit of the system being used, or a plurality of supply pumps being used (24, 34) feed into a common supply connection (P), or a single supply pump (24), which is preferably used for high-pressure delivery, comprises a plurality of supply lines, each of which is connected to one supply connection.

Description

Hydac Electronic GmbH, Hauptstraße 27, 66128 Saarbruecken

Motor-pump device

The invention relates to a motor pump device. Such devices are referred to in technical terms as motor-pump units and serve primarily to supply hydraulic circuits with hydraulic oil specifiable pressure. The units mentioned are usually characterized by a high power density with small dimensions and can be made available for the mentioned pressure oil supply oil hydraulic systems this as a functional unit.

Such a compact hydraulic unit is exemplified in DE 196 52 706 A1, which has a ring-cylindrical pressure medium container as a tank unit, which has an outer outer wall and an inner outer wall and two frontal flanges, with a closed by the pressure fluid container, cooled by a cooling air flow closed Electric motor and with a drivable by the electric motor hydraulic pump as a supply pump of the respective hydraulic circuit. The aim here is that such an aggregate builds in a very compact for continuous operation sufficient cooling of the electric motor, in particular in the form of an attachment. In the known solution, this is achieved in that the pressure medium container tightly surrounds the electric motor and the inner outer wall of the pressure medium container provided with cooling fins serves as a guide for the sweeping over the electric motor cooling air flow. In this way, the whole, between the Electric motor and the pressure fluid container through-flowing air is fully used for cooling the electric motor and also strokes the fan blades remote end windings of the electric motor closely to the housing along.

On the basis of this prior art, the object of the invention is to further improve the abovementioned units in such a way that, despite their compact design and high specific power, they are designed to be thermally advantageous in such a way that they operate in uninterrupted periodic operation (S6). up to continuous operation (S1) can be used informally.

A related object solves a motor-pump device, which is designed as a modular system, according to the feature configuration of patent claim 1 and a motor-pump device according to the feature configuration of claim 7.

With the features of claim 1 in its entirety, a motor-pump device for obtaining a variety of pressure combinations can be built in practice. Due to the mentioned use of different supply pumps, pump sizes, motors, mounting positions, tank lengths, etc., results in a very high variety of variants, which can be designed depending on the present application for the unit from a thermal point of view such that an uninterrupted periodic operation (S6) to for continuous operation (S1) is possible. The exact duty cycle is to be selected depending on the output power of the unit and the operating and environmental conditions such that a maximum allowable operating temperature, for example in the form of oil temperature in the unit, preferably not exceeded 80 ° C. For independent monitoring of the operating temperature preferably a temperature switch can be used in or outside the unit.

The peculiarities of the motor-pump device are based on the inventive flexible modular system according to the feature configuration of claim 1, which, inter alia, allows the combination of high and / or low pressure with only one unit. In this way, the realization of so-called. One to two-circle supply systems is possible. The unit according to the invention can be used both horizontally and vertically and the tank unit in the form of the oil tank can be flexibly adjusted to the respective required oil volume.

For the abovementioned modes of operation (S1 and S6), it has proven to be advantageous, in the sense of the feature configuration of claim 7, to provide for a motor-pump device that the housing of its tank unit is designed as an extruded profile and provided with cooling ribs along its outer circumference facing the surroundings is. Thanks to the preferably external electric motor and the mentioned finned tank outer profile, preferably made of aluminum material, the desired increased operating mode can be realized in this way. In particular, when using an integrated cooling system via at least one cooling channel in the continuous casting of the tank unit cooling measures can be additionally avoided, such as attaching a fan whose fan wheel is to be driven by a drive shaft of the electric motor next to the respective supply pump, resulting in corresponding losses in the Operation of the known units leads. Furthermore, it is therefore possible to dispense with an additional oil cooler in certain applications. Further advantageous embodiments of the solution according to the invention are the subject of the other dependent claims. In the following, the aggregate-type motor-pump device will be explained in more detail with reference to the drawing. This show in principle and not to scale representation of the

1 is a perspective oblique view of the engine

Pumping device as a whole;

Fig. 2 in the manner of a longitudinal section a side view of the

Motor pump device according to FIG. 1 in a vertically elevated construction;

Fig. 3 is a view through the motor-pump device along the

Line III - III in Fig. 2;

Fig. 4 to 6 in various views parts of a tank unit, as used for the motor-pumping device according to Figures 1 and 2 ..; and FIGS. 7 to 12 are different in the manner of hydraulic circuit diagrams

Possible applications of the motor pump device for various hydraulic single and dual circuit systems.

The motor-pump device according to the invention is suitable as a high-low-pressure unit especially for:

- presses and forming machines,

- clamping, clamping, loosening, indexing on machine tools,

- hydraulic tools as drive units,

- clamping hydraulics, - operation of lifting and panning equipment,

- auxiliary and auxiliary drives,

- other custom applications. For the pertinent applications, the motor-pump device shown as a whole from the outside in FIG. 1, as shown, can be used horizontally as well as vertically according to the longitudinal section of FIG. 2. The motor-pump device shown in FIG. 2 is designed as a modular system and has a designated as a whole with 10 electric motor. The electric motor 10 may consist of a conventional asynchronous machine with an outer stator 12 and an inner rotor 14 (see Fig. 2). The rotor 14 is connected in the usual way with a drive shaft 1 6 of the electric motor 10, which is rotatably mounted end in bearings 18. Between the end Lagerlager- len 18 yet another third bearing 20 is present, which is accommodated in the multi-part motor housing 22 of the electric motor 10 on an inner wall. Furthermore, the electric motor 10 can be equipped with or without fan; shown here in Fig. 1 and 2 with fan. 2, a radial piston pump 24 is installed below the motor housing 22 with a total of three pump elements 26 as shown in FIG. 3. Instead of three pistons or pump elements 26 and six piston or pump elements may be used for the radial piston pump , The mentioned three or six valve spring-controlled radial piston pump elements 26 are actuated independently of direction by an eccentric drive 28 which is driven by the external electric motor 10, via its drive shaft 16. Furthermore, the pump elements 26 shown in FIG. 3 are accommodated in a pump housing in the manner of an annular flange 30. This ring flange 30 is, as shown particularly in FIG. 2, taken between the electric motor 10 and a generally designated 32 tank unit of the motor pump device. The interior of the tank unit 32 serves to receive a predefinable amount of oil fluid. Furthermore, a gear pump 34 is integrated within the tank unit 32, the technical structure is customary and therefore not shown in detail. The gear pump 34 removes, seen in the direction of FIG. 2, on its underside via a removal nozzle 36 with filter element 45 fluid from the tank unit 32 for further promotion from the unit out in a single or dual circuit system of a hydraulic system (not dargestel lt ). Also, the radial piston pump 24 has a suction line 38 with filter element 39 for the purpose of filtering the oil removed from the tank 32 by means of the radial piston pump 24, which is also discharged from the hydraulic unit to the outside to a hydraulic consumers, as described above.

The output shaft 42 of the gear pump 34, which is shown only schematically and schematically in Fig. 2, is driven by the Antriebswel le 1 6 of the electric motor 1 0 via a so-called. Oldham coupling 44. In any case, the nozzle-like fluid-removal parts, including the suction lines 36 and 38, designed so that a fluid removal from the tank 32 can be carried out both in a horizontal mounting position of the unit according to the illustration of FIG. 1 and a vertical uprisings - tion of the unit as shown in FIG. 2 is possible. For filling the tank 32, the ventilation fi lter 40 can be seen (Fig. 1, 3).

What will become more apparent from FIGS. 7 to 12, the motor-pump device according to the invention can be equipped with radial piston pumps 24 and / or with gear pumps 34 that a pressure supply for hydraulic single and dual circuit systems is possible, and only in Low pressure (ND) or only in high pressure (HD) or according to low pressure (ND) and high pressure (HD) combined. It is provided according to the invention that the respective radial piston pump 24 of the high pressure supply and the respective used gear pump 34 is to serve the low pressure supply of a hydraulic circuit. Depending on the desired performance for the electric motor 10, this may be formed two- or four-pole, and is the unit shown in FIG. 1 only for pure low-pressure applications provided in continuous operation, shown in Fig. 1 from the outside damping ring 46 between the annular flange 30 and the housing 22 of the electric motor 10 also omitted or replaced due to another pump control.

In particular, for a single-circuit system, this can be supplied with high pressure (HD), low pressure (LP), high and low pressure (HN) and low pressure / low pressure (NN). In a two-circuit system, the supply of low pressure / low pressure (N-N), high pressure / high pressure (H-H) or with high low pressure (H-N). Depending on the type of supply with high pressure or with low pressure, according to the modular system presented here, only one radial piston pump 24 can be used as a high-pressure pump or only one gear pump 34 as a low-pressure pump; Otherwise, all other structural components, as shown by way of example in FIG. 2, are retained. Only in the case of pure low-pressure variants (N, NN, N-N) can a different motor-pump connection be used, depending on the application. The mentioned high-pressure pump can at flow rates of about

3l / minute quite provide 700 bar supply pressure. The low-pressure pump, however, has a higher flow rate up to, for example, 8.6 l / min at 250 bar or, for example, 20 l / min at 1 10 bar supply pressure. If two low-pressure supply pumps are combined with each other, one of the pumps can be switched to the non-pressurized circulation as needed in single-circuit operation (NN) to save energy become. Furthermore, the pumps can be operated alternately or in parallel in the two-circuit system (NN, HN, Hihi). The values are only examples and can be adjusted according to the application.

As is further apparent from FIG. 1, an electrical connection box 50 is present on the outer circumference of the motor housing 22. At the pump flange 30 is at least one longitudinal linkage, designated as a whole with 48, including valves attached. A level indicator of the container contents can be integrated for horizontal construction on a tank foot 62 and for vertical construction on the tank housing 52.

In FIGS. 4 to 6, the tank unit 32 is now reproduced in more detail. Thus, Fig. 4 shows the tank unit 32 in the manner of an exploded view with a housing 52 which is formed as an extruded profile, preferably made of aluminum. Along its outer periphery, the housing 52 on axially continuous cooling ribs 54, which are integral part of the extruded profile. The aforementioned cooling ribs 54 are interrupted by two flat profiles 56 and a flange plate 58 on the underside of the housing 52 in the circumferential direction. The two

Flat profiles 56 can be used to carry a machine plate unspecified by the manufacturer and as a further attachment a level gauge or sensor (not shown). The flange plate 58, on the other hand, serves for the horizontal elevation of the presented unit, as shown by way of example in FIG. Said flange plate 58 is an integral part of the inherently cylindrical housing body 52 of the tank unit 32 and is designed as a hollow profile, as shown in particular the representations of FIGS. 5 and 6, designed. Between the flange plate 58 and the cylindrical shell of the housing 52 extend along the tank unit 32, two cooling channels 60th 4, the housing 52 is accommodated between two add-on components 62, 64, wherein the right-hand connection component (tank foot) 62 seen in the viewing direction in FIG. 4 is used for the erection of the unit as shown in FIG 2, or the flange 62 has on the bottom side an attachment in the form of a filling level sensor 66, which then predetermines a horizontal installation position of the unit, as shown in FIG. The left-hand connection component (tank adapter) 64 seen in the viewing direction in FIG. 4 carries at its upper right end the filling nozzle 40 for the tank unit 32 and closes in succession, as shown in FIG. 1, against the annular flange 30 with the radial piston pump 24 at.

As is further apparent from FIG. 4, the two flanges 62, 64 have connection points 68 with which a cooling circuit (not shown in detail) can be realized, in which the coolant enters the connection point 68 of the tank foot 62 according to the arrow representations. is then forwarded to the two cooling channels 60 and collected by the tank adapter 64, the corresponding heated coolant on the junction 68, the tank unit 32 in turn leaves. Such an effective cooling of the tank contents is possible. While the shown cooling ribs 54 thus primarily serve for air and convection cooling of the tank contents, the cooling channels 60 enable integrated liquid cooling for the tank contents of the tank unit 32. As cooling medium, it would be advisable to use the cooling lubricant when using the aggregate in machine tools, since a cooling lubricant supply as a unit is often already integrated in the machine tool. However, other cooling media such as water, glycol, etc. are used. In this case, the cooling medium along the tank profile due to the temperature difference, the heat of the oil tank and thus also the hydraulic oil, which is stored in the tank unit 32. The coolant inlet is located at the tank foot 62 and the outlet at the tank adapter 64. By this cooling method is in certain cases a saturation of the oil temperature below the permitted max. Temperature reached. Correspondingly, electric motors with appropriate operating mode are used for the periodic uninterrupted operation up to continuous operation. Thus, the two thermal problem areas (oil temperature and engine temperature) of the hydraulic unit for the two modes mentioned are solved. Due to the integrated liquid cooling and a raised surface by the cooling fins 54 and good heat conduction through the use of the aluminum material for the housing 52 is a very good cooling of the hydraulic fluid before and it can be achieved higher operating modes and switch-on with the unit during operation. These cooling methods can be used both in the horizontal (FIG. 1) and in the vertical (FIG. 2) alignment of the unit. For a vertical installation situation, the through-holes 70 on the tank foot 62 can also be provided with screw connections, not shown. In the following, the individual system solutions will now be presented by means of examples according to FIGS. 7 to 12.

Thus, FIG. 7 shows a low-pressure recirculation system, wherein the gear pump designed as a low-pressure pump 34 feeds into a single supply port P of the hydraulic recirculation system (not shown). The fluid coming from the low-pressure system is returned to the tank unit 32 via the tank connection T for a new removal. The removal takes place via the removal nozzle 36 and the low-pressure filter element 45 connected thereto, so that the fluid then reaches the suction side of the gear pump 34. The ports P, T serve as an interface for fluid continuity to a not closer illustrated linking system of a hydraulic circuit, which is designed here as Einkreissystem. Furthermore, the gear pump 34 delivers the fluid to the supply port P of the single-circuit system on its pressure side.

The solution according to FIG. 8 is modified compared to the embodiment according to FIG. 7 insofar as now two low-pressure gear pumps 34 supply a common supply connection P. In this regard, one of the two pumps 34 can be switched to the non-pressurized circuit as needed to save energy, to work more efficiently and to enable a variable volume flow in two operating points.

In the embodiment according to FIG. 9, two gear pumps 34 for the low pressure are present and each pump 34 as a supply pump supplies its own supply connection P1 and P2. In the embodiments according to FIGS. 7 to 9, it is therefore possible to completely dispense with a radial piston pump 24 within the unit. For the solution according to FIGS. 8 and 9, instead of a single gear pump 34 according to FIG. 2, two gear pumps are to be provided. But it is also possible, right from the start to integrate several gear pumps 34 in the tank unit 32 and then take to implement the solution of FIG. 7, only one of the available gear pumps 34 in operation. Furthermore, it is also possible to replace the gear pump 34 provided for the low-pressure supply by a radial piston pump 24 with a lower power for the low-pressure supply, if necessary.

In the solution according to FIG. 10, only one radial piston pump 24 is used for a high-pressure supply of the single-circuit system, so that the gear pumps 34 provided for the low-pressure region are not provided within the unit. The radial piston pump 24 according to FIG. 10 conveys pressurized fluid into the pressure supply connection P with only one supply branch 72.

In the embodiment according to FIG. 11, a supply port P1 is supplied via a supply line 72 of the high-pressure radial piston pump 24, whereas the low-pressure gear pump 34 charges the further pressure supply port P2 with presettable pressure fluid. In this way, a two-circuit system is realized via the pressure supply connections PI, P2, once with high pressure (P1), once with low pressure (P2). But there is also the possibility in the sense of a single-circuit system, which is not shown in detail, the two supply ports P1, P2 in turn fluidly connect to each other via a valve within the concatenation, so that overall an increased volume flow (HN) is achieved compared to a solution Only a high-pressure pump, for example in the form of the radial piston pump 24 according to FIG. 10. Furthermore, thus, in the variant HN, switching between high and low pressure is possible, as is required, for example, in typical rapid-slip creeper circuits. In the solution according to FIG. 12, in turn, a dual-circuit system P1, P2 is realized, wherein this time each supply connection P1, P2 is assigned its own supply line 72, which is supplied by the radial piston pump 24. In particular, in a construction of the radial piston pump 24 with a plurality of pistons, for example, six pistons, a number of pistons, for example, three pistons or pump elements 26 can be assigned to the circle with the supply port P1 and the remaining piston or pump elements 26 then provide the second circle on the other Supply connection P2. As Fig. 1 illustrates, the unit appears by obvious adjustments of transitions of said components in a clearly structured Shape as a high-quality product with a clear visual order, which facilitates assembly and repair work. The reuse of these components in both horizontal and vertical mounting position and the realization of different system solutions and circuit variants is a very flexible modular system with a uniform structure. It may be cheaper in the context of the mentioned modular system to create an aggregate with a radial piston pump 24 and a gear pump 34 and as needed always only one of the two pumps 24, 34 or both pumps 24, 34 to operate in each case to design an independent high- or low-pressure unit, which only then has a respective specially adapted supply pump.

Claims

P a t e n t a n s p r u c h e

Motor-pump device, designed as a modular system, consisting of at least

an electric motor (10),

a radial piston pump (24), which can be driven by the electric motor (10), and which preferably serves a high-pressure supply, and/or a gear pump (34), which preferably serves a low-pressure supply,

a tank unit (32),

Attachments, such as valves (48) in longitudinal linkage and level meters (66), for the implementation of a hydraulic single or multi-circuit system,

- Each supply pump (24, 34) used has its own supply connection (P1, P2) for the respective circuit of the system used, or

several supply pumps (24, 34) used in a common supply connection (P), or

a single supply pump (24), which is preferably used for high-pressure delivery, has several supply lines (72), each of which is connected to a supply connection

(PI, P2) are connected.

Motor-pump device according to claim 1, characterized in that the respective radial piston pump (24) is accommodated between the electric motor (10) and the tank unit (32).

3. Motor-pump device according to claim 1 or 2, characterized in that the respective gear pump (34) is accommodated in the tank unit (32).

4. Motor-pump device according to one of the preceding claims, characterized in that the electric motor (10) with a common drive shaft (26) drives both the respective radial piston pump (24) and the gear pump (34).

5. Motor-pump device according to one of the preceding claims, characterized in that the electric motor (10) has an external motor housing (22) which is connected to the environment and to which the pump housing (30) of the supply pump (24, 34) is connected , which in turn is followed by a housing (52) of the tank unit (32).

6. Motor-pump device according to one of the preceding claims, characterized in that the electric motor (10), the supply pump (24, 34) and the tank unit (32) are the essential components of the modular system.

7. Motor-pump device according to one of the preceding claims, characterized in that a rotor (14) of the electric motor (10) is connected to a drive shaft (16) of the same, which is rotatably mounted at the end in bearing points (18) and that between the ends - Side bearing points (18) there is another third bearing point (20), which is accommodated on an inner wall in the multi-part motor housing (22) of the electric motor (10).

Motor-pump device close to one of the preceding claims, characterized in that the electric motor (10) is an asynchronous machine, with an external stator (12) and the internal rotor (14).

Motor-pump device according to one of the preceding claims, characterized in that a valve is attached longitudinally to the pump flange (30).

10.Motor-pump device according to one of the preceding claims, characterized in that the pistons (26) of the radial piston pump (24) can be driven via an eccentric drive (28) of the drive shaft (26) of the electric motor (10) and / or the output shaft (42 ) of the gear pump (34) is connected to the drive shaft (26) of the electric motor (10) via an Oldham coupling (44).

1 1 .Motor pump device, consisting of at least

an electric motor (10),

a supply pump (24, 34) that can be driven by the electric motor (10) and

a tank unit (32),

characterized in that the housing (52) of the tank unit (32), designed as an extruded profile, is provided with cooling fins (54) along its outer circumference facing the environment.

12. Motor-pump device according to claim 7, characterized in that the housing (52) of the tank unit (32) is designed as a cylindrical body and that a flange plate (58) is arranged along its outer circumference, which merges integrally into the cylindrical body and that This flange plate (58) allows the motor-pump device to be installed in a horizontal installation position and a tank foot (62) allows the vertical installation position.

1 3. Motor-pump device according to claim 7 or 8, characterized in that integrated into the jacket of the housing (52) of the tank unit (32), preferably at the transition point between the flange plate (58) and the cylindrical jacket of the housing (52), at least a cooling channel (60) is present.

14. Motor pump device according to one of claims 7 to 9, characterized in that the housing (52) of the tank unit (32) has at its front ends the tank foot (62) for supporting the motor pump device in a vertical orientation and on the other hand has a further tank adapter (64) for connecting the annular flange (30) to the respective radial piston pump (24).