CN113994103B

CN113994103B - Hydraulic control block and servo hydraulic shaft having the same

Info

Publication number: CN113994103B
Application number: CN202080046558.7A
Authority: CN
Inventors: M·伦佩尔; J·施瓦克
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2019-06-27
Filing date: 2020-06-18
Publication date: 2024-07-12
Anticipated expiration: 2040-06-18
Also published as: CN113994103A; DE102019209322A1; WO2020260128A1

Abstract

The application relates to a hydraulic control block for a servo hydraulic shaft, in particular a linear shaft, having at least a hydraulic connection for hydraulically connecting a hydraulic actuator of the shaft and having a first chamber in which a hydraulic machine or at least a power transmission assembly of the hydraulic machine can be at least partially accommodated for the supply of pressure medium to the actuator. A servo hydraulic shaft with the hydraulic control block is also disclosed.

Description

Hydraulic control block and servo hydraulic shaft having the same

Technical Field

The present invention relates to a hydraulic control block and a servo hydraulic shaft having the same.

Background

The force development of the hydraulic actuator, for example a hydraulic cylinder, by the servo hydraulic shaft, in particular the linear shaft, in particular in a closed circuit and with a small oil quantity, is coordinated with the dynamics, accuracy and flexible crosslinkability of the electrically controllable actuator, for example a servo motor. It is thus possible to squeeze, engage or close with large axial forces and at the same time to position it in the micrometer range. Generally involving a linear motion. Solutions in semi-closed loops are also possible.

The data page RD 08137/2018-02 of the present inventors shows a servo hydraulic axis of this type. The shaft of compact construction has a servo actuator, a hydraulic cylinder, a hydraulic accumulator and control elements like for example valves and power electronics.

In particular, in the case of small available installation space, a compact, installation space-optimized solution is important. Thus, in addition to the exploded form of the shaft, in which the components mentioned are connected to the central hydraulic control block by hoses, lines, pipes, compact forms with direct mechanical and hydraulic and electrical connections to the control block are also possible. Improvements in the form of the compact design in terms of space utilization and energy efficiency are a continuing desire.

Disclosure of Invention

In contrast, the object of the present invention is to provide a hydraulic control block for a servo hydraulic shaft, which reduces the installation space requirement of the shaft while maintaining the same or improved energy efficiency. The invention also provides a servo hydraulic shaft with the hydraulic control block.

The first task is solved by a hydraulic control block and the second task is solved by a servo hydraulic shaft. The hydraulic control block for a servo hydraulic shaft, in particular a linear shaft, has at least a hydraulic interface for hydraulically connecting a hydraulic actuator of the shaft and has a chamber in which a hydraulic machine or at least a drive train component of the hydraulic machine can be received at least in part for the supply of pressure medium to the actuator, or in which the hydraulic machine is flanged or cannulated, characterized in that a second chamber is preferred in which a filter element for filtering the pressure medium can be received or at least in part be received. The servo hydraulic shaft has a hydraulic control block according to the invention and has at least a hydraulic actuator hydraulically connected thereto, a hydraulic machine for pressure medium supply of the hydraulic actuator and a filter element for filtering the pressure medium, which filter element is received in a preferably second chamber.

Advantageous refinements of the hydraulic control block are described below.

The hydraulic control block for the servo hydraulic shaft, in particular for the linear shaft, has at least a hydraulic connection for hydraulically connecting a hydraulic actuator, in particular a hydraulic cylinder, of the shaft. Preferably, the hydraulic control block further has a mechanical interface for mechanically connecting the actuator. Preferably, a mechanical interface for connecting an electrical actuator, in particular a servo actuator, is also provided. According to a first variant of the pressure medium supply for the hydraulic actuator, the hydraulic machine or at least a power transmission assembly of the hydraulic machine can be at least partially accommodated in the (first) chamber of the control block. The hydraulic machine can also be flanged or cannulated onto the block. According to the invention, a (second) chamber is provided in which a filter element for filtering the pressure medium can be received or accommodated at least in part.

Since the filter or filter element is no longer arranged outside but in the naturally occurring central hydraulic component of the control block, a servo hydraulic shaft with a smaller installation space requirement can be realized. A separate filter housing is omitted, since the filter housing is now formed by the control block. Furthermore, by this arrangement, the filter can be fed in the vicinity of the hydraulic pump via very short inlets and outlets. This reduces the pressure loss. In summary, the structural space requirement of the shaft is reduced, while the energy efficiency remains the same or is improved.

The cylinders can be cannulated, flanged, or integrated. The additional units can be fed (semi-closed loop).

The control block preferably has a switching valve and additionally a safety valve, so that different drive modes of the hydraulic and/or electric actuator can be switched and protected.

The filter element is preferably a filter cartridge.

The opening of the second chamber is arranged in an easily accessible manner at the outer surface of the control block for quick replacement of the filter element.

Preferably, the inlet and outlet of the second chamber are fluidly connected to the suction and pressure ports of the first chamber or the suction and pressure sides of the hydraulic machine, respectively, by passages constructed in the control block.

The filter can also be integrated in the low-pressure circuit preceding the hydraulic machine.

Preferably, the second chamber is closed off outwardly by a closing element, in particular a closing screw.

In one development, the chambers are separated along the direction of extension of the control block and are arranged with at least partial overlap along a transverse direction relative to the direction of extension of the control block, whereby the control block is configured smaller in both directions.

In a refinement which saves installation space, the outer circumferential surface section is formed by a largely constant offset relative to the second chamber or its inner circumferential surface.

One development is to realize the chamber partly or entirely by casting.

The control block is preferably cast, wherein at least one of the chambers is shaped by means of a casting core. Additionally, the chamber can be drilled or milled to reach its final dimensions.

In one development, the second chamber is configured such that the filter, the filter element can be fed at different positions, whereby in particular inlet optimization or flow path optimization can be achieved.

In a further development, a pressure medium flow path, in particular an inflow channel, is provided, in particular connecting the first chamber or the hydraulic machine with the second chamber. The pressure medium flow path has an inlet opening in an inner peripheral surface of the second chamber.

In one refinement, the inner circumferential surface extends circumferentially around the insertion axis of the second chamber for the filter element. Cylindrical chambers are also possible.

The pressure medium flow path advantageously has a directional component tangential to the inner circumferential surface at least at the inlet opening.

The inlet opening can optionally be embodied by the casting core in a still more flow-optimized manner.

In order to improve the separation, reduce the pressure loss caused by the filter element and increase the service life thereof, in one refinement, the inner circumferential surface of the second chamber has a cutout which extends helically around the insertion axis of the second chamber. The slit imparts a cyclonic flow pattern ("swirl") to the pressure medium, which causes a separation at the bottom of the second chamber that is independent of the filtering action of the filter element.

In a further development, the cutout starts directly from the inlet opening of the second chamber or in a spaced-apart manner from the inlet opening.

In a development, the cutout extends circumferentially or at least once completely circumferentially around the insertion axis.

In this case, the cross-sectional shape which is advantageous in terms of flow technology is a truncated semicircular or oval cross-section of the cutout.

The depth to width ratio of the cross section of the cut is preferably between 1:10 and 1:5, in particular about 1:7.

The spiral shape can be milled or realized by additional components.

In a variant, the insertion axes of the first chamber for the hydraulic machine or the power transmission assembly and of the second chamber for the filter element are parallel, transverse or perpendicular to each other.

The servo hydraulic shaft has a hydraulic control block constructed in accordance with at least one aspect of the foregoing description. Furthermore, the servo hydraulic shaft has at least a hydraulic actuator hydraulically connected thereto, a hydraulic machine for pressure medium supply thereto and a filter element for filtering the pressure medium, the hydraulic machine or a power transmission assembly thereof being received in the first chamber and the filter element being received in the second chamber.

Since the filter or filter element is now no longer arranged externally, but in the naturally occurring central hydraulic component of the control block, the servo hydraulic shaft has a smaller installation space requirement. A separate filter housing that would otherwise be necessary is omitted. The filter housing is now formed by a control block. Furthermore, with this arrangement, the filter is fed and unloaded near the hydraulic pump through very short inlets and outlets. This reduces the pressure loss. In summary, the structural space requirement of the shaft is reduced, while the energy efficiency remains the same or is improved.

Drawings

In the drawings, one embodiment of a hydraulic control block according to the invention and a servo hydraulic shaft according to the invention are shown. The invention will now be explained more closely with the aid of the figures of the accompanying drawings.

Wherein:

Figure 1 shows a side view of a servo hydraulic shaft according to the invention according to one embodiment,

Figure 2 shows in a partially transparent bottom view the hydraulic control block according to the invention of the servo hydraulic shaft according to figure 1,

Figure 3 shows in a partial perspective view a hydraulic control block according to figure 2,

Figure 4 shows the hydraulic control block according to figures 2 and 3 in a partially transparent top view,

Fig. 5 shows the region of the filter receptacle of the hydraulic control block according to the preceding figures in a partially transparent side view, and fig. 6 shows the filter receptacle according to fig. 5 together with the filter element inserted in a longitudinal section.

Detailed Description

The servo hydraulic shaft 1 according to fig. 1 has a hydraulic actuator 2 designed as a hydraulic cylinder or hydraulic cylinder, by means of which hydraulic actuator 2 an axial force can be applied to a tool or workpiece for pressing, engaging, closing and/or positioning, the servo hydraulic shaft 1 furthermore has an electric actuator 4 designed as a servo motor and supplied by a power electronics 6, a hydraulic accumulator 8 for storing and recovering the hydrostatic energy of the hydraulic cylinder 2, and a hydraulic control block 10, which hydraulic control block 10 is arranged centrally, and the mentioned components 2, 4 and 8 and further valve control means 12 for controlling the hydraulic cylinder 2 are arranged and/or fastened and/or flanged and/or cannulated to the hydraulic control block 10. The compact design shown in fig. 1 is particularly space-saving, but can also be designed in a partially or completely exploded manner. In this case, the hydraulic assemblies 2 and 8 mentioned in particular (only 2 is also possible) are removed from the control block 10 and connected to hydraulic bushings or hoses.

The pressure medium of the hydraulic cylinder 2 used in operation flows in a closed hydraulic circuit, which essentially consists of a control block 10, a hydraulic pump (not shown) accommodated therein and the hydraulic cylinder 2. In this case, the pressure medium needs to be filtered continuously. The servo hydraulic shaft 1 thus also has a hydraulic filter with a filter element (not shown in fig. 1) which is integrated according to the invention into the hydraulic control block 10, which is shown in more detail by means of the following figures. The low-pressure circuit can also be supplied by a unit.

Fig. 2 to 4 show a top view, a perspective view and a bottom view, respectively, of the control block 10 according to fig. 1. The illustration is chosen partly transparent, wherein the outer wall of the control block 10 allows to see into its interior, whereas the chambers, pressure medium channels and other recesses in the control block 10 are shown as opaque walls. In particular, fig. 3 shows a second chamber 14 embodied as a filter element receptacle, into which second chamber 14a filter element can be inserted.

By means of the arrangement of the filter element or the filter integrated in the control block 10, a more direct hydraulic actuation and pressure medium application of the filter element of the servo hydraulic shaft 1 and at the same time a more compact construction thereof can be achieved. This results in a smaller installation space requirement and in a more compact look and feel of the servo hydraulic shaft 1, since the filter is now "invisible" accommodated in the control block 10.

Furthermore, by means of this integration, a shortening of the inlet to the filter element and the outlet from the filter element is provided, so that the length of the pressure medium pipe or hose to be installed can be reduced. This reduction of the pressure-elastic component improves the controllability of the shaft 1 and furthermore reduces the length-dependent pressure loss along the relevant flow path.

According to fig. 2, the hydraulic control block has a longitudinal axis 18, which longitudinal axis 18 extends transversely to the longitudinal axis 16 of the hydraulic cylinder 2 according to fig. 1, and a plane of symmetry extends through the longitudinal axis 18, which at least relates to the lateral outer circumferential surface of the hydraulic control block 10. The extension axis 21 of the receptacle 14 is arranged in this plane of symmetry.

The control block 10 has raised connection surfaces 24 on its longitudinal or lateral sides 20, 22, which are arranged symmetrically to the symmetry plane, for compact and space-saving connection of the valve device 12 according to fig. 1. At the upper side 26 of the control block 10, which is partly parallel to the lower side 28, a recess 30 is provided for receiving a hydraulic pump (not shown) or at least a power transmission assembly of the hydraulic pump.

According to fig. 4, the recess 30 or the first chamber 30 has a high-pressure connection 34 and a further high-pressure connection 36 at its bottom 32, since pressure can be built up in both pump rotational directions in a closed circuit. The high-pressure connections 34, 36 are connected via pressure medium channels, which are not described further, formed in the control block 10 to connections for the pressure medium supply to the hydraulic cylinders 2.

In order to save even more space, the outer circumferential surface of the control block 10 according to fig. 3 at the lower side 28 is not parallel to the upper side 26 in the region of the second chamber 14, but is offset d only relative to the inner circumferential surface 38 of the second chamber 14.

The control block 10 is at least partially narrower on both sides of the extended second chamber 14, i.e. in the direction of the sides 20, 22, than the remaining section of the control block.

At least one connection device for, in particular, a hydraulic component is provided at least one transition of the narrower section to the remaining section, in particular at a shoulder of the control block 10 formed there.

For the same purpose of saving structural space, the control block 10 has narrowing or bevels 42, 44 at the upper side 26 and lower side 28 of the end section 40 arranged directly opposite the second chamber 14 or filter receiver 14.

The same applies to the underside 28 extending in a lateral longitudinal direction at the middle section of the control block 10, as shown in fig. 3. Here too, a bevel is provided at the hydraulic control block 10.

The flow direction of the second chamber 14 and the pressure medium to be filtered will now be described with reference to fig. 5. In fig. 5 and 6 the grass draws the flow path from the inlet a to the outlet F. Fig. 6 shows a longitudinal section through the extension axis 21 of the second chamber 14 in the mentioned symmetry plane of the control block 10, and thus also through the extension axis, according to fig. 6 the inlet opening 46 of the inlet a is arranged in the lateral bottom region B of the second chamber 14. At the inlet opening 46, the pressure medium flow path of the inflowing pressure medium, in particular the inflow channel leading there, has a directional component tangential to the inner circumferential surface 38. Preferably, the inner peripheral surface of the inlet opening 46 is tangentially transformed into the inner peripheral surface 38.

Preferably, the inlet opening 46 is designed such that in its region the pressure medium flow path is directed into an annular space 48 formed between the filter element 50 and the inner circumferential surface 38. In this way, the filter element 50 is mechanically protected, since it is not directly acted upon by radial flow. This results in an improved durability of the filter element 50 and an extended maintenance interval. A smaller load can also be used for a smaller size of the filter element 50, so that again a space saving can be achieved.

In the inner circumferential surface 38, a cutout recess 52 extending helically around the extension axis or the insertion axis 21 is connected to the inlet opening 46. As can be seen from fig. 6, the cutout recess 52 has a semi-elliptical cross section which is greatly truncated in the exemplary embodiment, as can be seen better in the regions C and D. The three-dimensional helical extension of this slit 52 is evident when viewing fig. 5.

From the inlet region B, the pressure medium flows along the cutout 52, which is also outside the cutout 52 due to turbulence and undesired flow guidance, through the annular space 48, here through the cross section C, the cross section D and is deflected there in the radial direction onto the filter element 50. There, the pressure medium flows through the filter element 50 and into the central outlet pipe 54 thereof. On the (preferably left) side to the outlet opening there is an adapter which centers the element. The pressure medium continues to flow up to a cross section F, which represents the outlet of the bottom side of the filter element 50. By the spiral flow, a separation effect of cyclone is superimposed on the filtering effect and separation of impurities is further improved.

The penetration area E extends over the entire filter element. The spiral shape causes a revolution around the filter element.

A hydraulic control block for a servo hydraulic shaft is disclosed, having a filter or filter element received in the control block or at least having a chamber provided for this purpose.

A servo hydraulic shaft having the hydraulic control block is also disclosed.

Claims

1. Hydraulic control block for a servo hydraulic shaft (1), having at least a hydraulic interface for hydraulically connecting a hydraulic actuator (2) of the shaft (1) and having a first chamber (30), in which first chamber (30) a hydraulic machine or a drive train assembly of at least the hydraulic machine can be accommodated at least in part for the supply of pressure medium to the actuator (2), or in which the hydraulic machine is flanged or cannulated, characterized by a second chamber (14), in which second chamber (14) a filter element (50) for filtering the pressure medium can be accommodated or accommodated at least in part, wherein an inner circumferential surface (38) of the second chamber (14) has a cutout (52), the cutout (52) extending helically around a filling axis (21) of the second chamber (14).

2. Control block according to claim 1, wherein the servo hydraulic axis (1) is a linear axis.

3. Control block according to claim 1 or 2, wherein the first chamber (30) and the second chamber (14) are spaced apart along the direction of extension of the control block (10) and arranged in at least partial overlap along a transverse direction (18) with respect to the direction of extension of the control block (10).

4. A control block according to claim 1 or 2, having an outer peripheral surface section with an offset (d) relative to the second chamber (14).

5. The control block of claim 4, the offset (d) being constant.

6. Control block according to claim 1 or 2, which is cast, wherein at least one of the first chamber (30) and the second chamber (14) is shaped and/or drilled by means of a casting core.

7. Control block according to claim 1 or 2, having a pressure medium flow path connectable or connected to the hydraulic machine, the pressure medium flow path having an inlet opening (46) in the inner circumferential surface (38) of the second chamber (14).

8. Control block according to claim 7, the pressure medium flow path being an inflow channel (a).

9. Control block according to claim 7, wherein the inner circumferential surface (38) extends circumferentially around a loading axis (21) for the second chamber (14) of the filter element (50).

10. Control block according to claim 7, wherein the pressure medium flow path has a directional component tangential to the inner circumferential surface (38) at least at the inlet opening (46).

11. Control block according to claim 7, wherein the cutout (52) starts at an inlet opening (46) or in a spaced-apart manner from the inlet opening (46).

12. Control block according to claim 1 or 2, wherein the cutout (52) extends circumferentially or at least once completely circumferentially around the loading axis (21).

13. Control block according to claim 1 or 2, wherein the cutout (52) has a truncated semicircular or elliptical cross section (C, D).

14. Control block according to claim 1 or 2, wherein the cut-out (52) has a depth to width ratio between 1:10 and 1:5.

15. The control block of claim 14, wherein the cutout (52) has a depth to width ratio of 1:7.

16. Control block according to claim 9, wherein the loading axis of the first chamber (30) for the hydraulic machine or the power transmission assembly is parallel or successive or in rows or transverse or perpendicular to the loading axis (21) of the second chamber (14) for the filter element (50).

17. -A servo hydraulic shaft having a hydraulic control block (10) configured according to any one of claims 1 to 16, and having at least a hydraulic actuator (2) hydraulically connected at the hydraulic control block (10), a hydraulic machine for pressure medium supply of the hydraulic actuator (2) and a filter element (50) for filtering the pressure medium, the filter element (50) being received in the second chamber (14).