WO2020260128A1

WO2020260128A1 - Hydraulic control block and servo-hydraulic axle comprising the control block

Info

Publication number: WO2020260128A1
Application number: PCT/EP2020/066946
Authority: WO
Inventors: Manuel Rumpel; Johannes Schwacke
Original assignee: Robert Bosch Gmbh
Priority date: 2019-06-27
Filing date: 2020-06-18
Publication date: 2020-12-30
Also published as: CN113994103B; CN113994103A; DE102019209322A1

Abstract

The invention relates to a hydraulic control block for a servo-hydraulic axle, in particular a linear axle, at least comprising hydraulic interfaces for hydraulically connecting a hydraulic actuator of the axle and comprising a first cavity in which a hydraulic machine or at least drive components thereof can be received at least in some sections in order to supply a pressure medium to the actuator. The invention additionally relates to a servo-hydraulic axle comprising the control block.

Description

Hydraulic control block and

servohydraulic axis with the control block

description

The invention relates to a hydraulic control block according to the preamble of

Claim 1 and a servohydraulic axis with the control block according to Claim 14.

A servohydraulic axis, in particular a linear axis, combines the force development of hydraulic actuators, for example a hydraulic cylinder, especially in a closed circuit and with a low oil volume, with the dynamics, precision and flexible networking of an electrically controllable actuator, for example a servo motor. It can therefore be pressed, joined or closed with high axial force and at the same time positioned in the micrometer range. Generally it is a linear movement. Concepts in a semi-closed cycle are also possible.

A generic servohydraulic axis is shown in data sheet RE 08137 / 2018-02 from the applicant. The compact axis has a servo actuator, a

Hydraulic cylinders, a hydraulic accumulator and control elements such as valves, as well as power electronics.

Compact, space-optimized solutions are particularly important in the case of small installation spaces available. In addition to the resolved designs of the axis, in which the components mentioned are connected to a central hydraulic control block by hoses, lines, and pipes, there are therefore compact designs with direct mechanical and

hydraulic and electrical connection to the control block possible. Their improvement in terms of space utilization and energy efficiency is a permanent concern. In contrast, the invention is based on the object of creating a hydraulic control block for a servohydraulic axis which reduces the installation space requirement of the axis while maintaining or improving energy efficiency. Another object of the invention is to create a servo-hydraulic axis with the hydraulic control block.

The first object is achieved by a hydraulic control block with the features of claim 1, the second by a servohydraulic axle with the features of claim 14.

Advantageous developments of the hydraulic control block are described in the respective dependent claims.

A hydraulic control block for a servo-hydraulic axis, in particular for a linear axis, has at least hydraulic interfaces for the hydraulic connection of a hydraulic actuator, in particular a hydraulic cylinder, of the axis. It preferably also has mechanical interfaces for the mechanical connection of the actuator. Mechanical interfaces are preferably also provided for connecting an electrical, in particular a servo actuator. In a (first) cavity of the control block, according to a first variant for supplying pressure medium to the hydraulic actuator, a hydraulic machine, or at least its engine components, can be accommodated at least in sections. The hydraulic machine can also be flanged on or piped to form a block. According to the invention, a (second) cavity is provided in which a filter element for filtering the pressure medium can be received or received at least in sections.

Since the filter or the filter element is no longer arranged outside, but in the central hydraulic component of the control block, which is already present, there is a

Servohydraulic axis with less space requirement. There is no need for a separate filter housing, as this is now formed by the control block. This arrangement also makes it possible to feed the filter near the hydraulic pump via an extremely short inlet and outlet. This lowers the pressure loss. In total, the installation space requirement of the axis is constant or improved

Energy efficiency reduced. The cylinder can be piped, flanged or integrated. The low pressure can be supplied by an additional unit (semi-closed circuit).

The control block preferably carries switching valves and, in addition, safety valves, so that different drive modes of the hydraulic actuator and / or the electric actuator can be switched and safeguarded.

The filter element is preferably a filter cartridge.

An opening in the second cavity is arranged in an easily accessible manner on an outer surface of the control block for quick replacement of the filter element.

An inlet and outlet of the second cavity are preferably each via an im

Control block formed channel with a suction and a pressure opening of the first cavity or a suction and pressure side of the hydraulic machine fluidically connected.

The filter can also be integrated in the LP circuit in front of the hydraulic machine.

Preferably, the second cavity is outwardly from a closure element,

in particular closed by a screw plug.

In a further development, the cavities are spaced apart in a direction of extent of the control block and are arranged with an overlap at least in sections in a direction transverse to this, whereby the control block is small in both directions.

In a development that saves installation space, an outer jacket surface section is formed by a predominantly constant offset to the second cavity or its inner jacket surface.

A further development is the realization of the cavities partially or entirely by casting.

The control block is preferably cast, with at least one of the cavities being originally formed by means of a cast core. In addition, the cavity can be drilled or milled in order to achieve its final dimensions. In one development, the second cavity is designed in such a way that the filter, the

Filter element, can be fed at different points, whereby in particular an inlet or flow path optimization is possible.

In a further development, a pressure medium flow path, in particular an inlet channel, is provided, in particular connecting the first cavity or the hydraulic machine to the second cavity. This has an inlet opening in an inner lateral surface of the second cavity.

In a further development, the inner jacket surface extends circumferentially around an insertion axis of the second cavity for the filter element. A cylinder cavity is also possible.

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

The inlet mouth can optionally be made flow-optimized with a cast core.

In order to improve the separation, to reduce a pressure loss over the filter element and to increase its service life, in a further development the inner surface of the second cavity has a depression which extends helically around the insertion axis of the second cavity. This impresses a cyclonic flow shape (a “swirl”) on the pressure medium, which leads to a deposition on a bottom of the second cavity that is independent of the filtering effect of the filter element.

In a further development, the depression arises directly from an inlet opening of the second cavity, or it arises at a distance from it.

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

A cross-sectional shape that is favorable in terms of flow technology is a flattened semicircular or elliptical cross-section of the depression.

A ratio of depth to width of the cross section of the depression is preferably between 1:10 and 1: 5, in particular approximately 1: 7. The helix shape can be milled or implemented using an additional component.

In variants there are insertion axes of the first cavity for the hydraulic machine or

Engine components and the second cavity for the filter element parallel, transverse or perpendicular to each other.

A servohydraulic axle has a hydraulic control block which is designed in accordance with at least one aspect of the preceding description. It also has an at least hydraulically connected hydraulic actuator, a hydraulic machine for its pressure medium supply, which or its engine components is or are received in the first cavity, and a filter element for filtering the pressure medium which is received in the second cavity.

Since the filter or the filter element is no longer arranged outside, but in the central hydraulic component of the control block that is already present, the servohydraulic axis requires less space. The otherwise necessary, separate filter housing is not required. This is now formed by the control block. This arrangement also means that the filter near the hydraulic pump is fed and relieved via an extremely short inlet and outlet. This lowers the pressure loss. All in all, the installation space requirement of the axis is reduced with the same or improved energy efficiency.

One embodiment of a hydraulic control block according to the invention and a servo-hydraulic axis according to the invention are shown in the drawings. The invention will now be explained in more detail with the aid of the figures of this drawing.

Show it:

Figure 1 is a side view of a servo-hydraulic axis according to the invention according to an embodiment

FIG. 2 shows a hydraulic control block according to the invention of the servohydraulic axis according to FIG. 1 in a partially transparent view from below,

3 shows the hydraulic control block according to FIG. 2 in a partial perspective view, FIG. 4 shows the hydraulic control block according to FIGS. 2, 3 in a partially transparent view from above,

FIG. 5 shows the area of a filter holder of the hydraulic control block according to FIGS

previous figures in a partially transparent side view, and 6 shows the filter holder according to FIG. 5 with an inserted filter element in one

Longitudinal section.

According to FIG. 1, a servohydraulic axis 1 has a hydraulic actuator 2 designed as a hydraulic or hydraulic cylinder, via which axial forces for pressing, joining, closing and / or positioning can be applied to a tool or workpiece, and also an electrical actuator 4, which acts as a servo motor designed and from a

Power electronics 6 is supplied, a hydraulic accumulator 8 for storing and recuperating hydrostatic energy of the hydraulic cylinder 2, as well as a hydraulic control block 10, which is arranged centrally and on which the named components 2, 4 and 8, as well as further valve control devices 12 for controlling the hydraulic cylinder 2 are arranged and / or attached and / or flanged and / or piped. The compact design shown in Figure 1 is particularly space-saving, but can also be designed partially or completely in a broken-up arrangement. In this case, in particular the hydraulic components 2 and 8 (only 2 is also possible) are out of place from the control block 10 and connected with hydraulic piping or tubing.

A pressure medium of the hydraulic cylinder 2 used during operation flows in the closed hydraulic circuit, which essentially flows out of the control block 10, one in it

recorded hydraulic pump (not shown) and the hydraulic cylinder 2 is formed. Continuous filtering of the pressure medium is necessary. The servohydraulic axis 1 therefore also has a hydraulic filter with a filter element (not shown in FIG. 1) which, according to the invention, is integrated in the hydraulic control block 10, which is shown in more detail with reference to the following figures. The low-pressure circuit can also be fed by an aggregate.

Figures 2 to 4 each show a view of the control block 10 according to Figure 1 from above, in perspective and from below. The representation is selected to be partially transparent, the outer walls of the control block 10 allowing a view of its interior, and cavities, pressure medium channels and other recesses in the control block 10, however, being shown with non-transparent walls. In particular, Figure 3 shows a as

A second cavity 14 formed in the filter element receptacle and into which a filter element can be inserted. An arrangement of a filter element or a filter integrated in the control block 10 enables a more direct hydraulic control and pressurization of the filter element of the servo-hydraulic axis 1 and, at the same time, its even more compact structure. This leads to a smaller space requirement and to a

The servo-hydraulic axis 1 looks more compact, as the filter is now housed “invisibly” in the control block 10.

This integration also shortens the inlet and outlet to and from the filter element, so that a length of pressure medium pipes or hoses to be installed can be reduced. This reduction in pressure-elastic components improves the controllability of axis 1 and also reduces a length-dependent pressure loss along the flow paths concerned.

According to Figure 2, the hydraulic control block has a transversely to the longitudinal axis 16 of the hydraulic cylinder 2 according to Figure 1 extending longitudinal axis 18 through which a

The plane of symmetry, at least as far as the lateral outer surface of the hydraulic control block 10 is concerned, extends. The axis of extension 21 of the receptacle 14 is arranged in this plane of symmetry.

On its longitudinal sides or lateral sides 20, 22 arranged symmetrically to the plane of symmetry, the control block 10 has raised connection surfaces 24 for the compact and space-saving connection of valves of the valve device 12 according to FIG. On its upper side 26, which is partially parallel to the lower side 28, there is a recess 30 for receiving the hydraulic pump (not shown), or at least from

Engine components of the hydraulic pump are provided.

This recess 30 or first cavity 30 has a high pressure connection 34 and a further high pressure connection 36 on its bottom 32 according to FIG

closed circuit, a pressure build-up is possible in both pump directions. The high-pressure connections 34, 36 are not described further, formed in the control block 10 pressure medium channels with connections for the pressure medium supply of the

Hydraulic cylinder 2 connected. For an even greater saving in installation space, the outer lateral surface of the control block 10 according to FIG.

The control block 10 is at least partially narrower than a remaining section of the control block on both sides of the extending second cavity 14, that is to say in the direction of the side surfaces 20, 22.

At at least one transition from the narrower section to the remaining section,

in particular on a shoulder of the control block 10 formed there, at least one connection device is provided for an in particular hydraulic component.

With the same aim of saving installation space, the control block 10 has a taper or incline 42, 44 on the upper side 26 and lower side 28 of an end section 40 arranged diametrically opposite the second cavity 14 or filter receptacle 14.

The same applies to the underside 28 in a lateral longitudinal extension on a central section of the control block 10, as shown in FIG. Here too, roofs are provided on the hydraulic control block 10.

With reference to FIG. 5, the second cavity 14 and a flow profile of the pressure medium to be filtered will now be described. A flow course from an inlet A according to FIG. 1 to an outlet F is sketched in FIGS. 5 and 6. According to Figure 6, the one

A longitudinal section in the mentioned plane of symmetry of the control block 10, and thus also through the axis of extent 21 of the second cavity 14, shows an inlet opening 46 of the inlet A in a lateral bottom area B of the second cavity 14. At the inlet opening 46, a pressure medium flow path of the inlet pressure medium, in particular the inlet channel opening there, has a directional component that is tangential to the inner lateral surface 38. An inner lateral surface of the inlet opening 46 preferably merges tangentially into the inner lateral surface 38.

Preferably, the inlet opening 46 is designed such that the pressure medium flow path in its area in a between a filter element 50 and the Inner circumferential surface 38 has formed annular space 48. This is how it is

The filter element 50 is mechanically protected as it is not directly exposed to a radial flow. This increases the durability of the filter element 50 and extends the maintenance interval. The lower stress can also be used to reduce the dimensions of the filter element 50, which in turn can save installation space.

A recess 52, which extends helically around the extension or insertion axis 21, adjoins the inlet opening 46 in the inner lateral surface 38. As can be seen from FIG. 6, this has a semi-ellipsoidal cross section which is strongly flattened in the exemplary embodiment, which is clearly visible in areas C and D. When looking at FIG. 5, the 3-dimensional, helical extension of this depression 52 becomes clear.

From the mouth area B, the pressure medium flows through the recess 52 - due to turbulence and non-ideal flow guidance also outside it - the annular space 48, passing through the cross section C, the cross section D and is deflected there in the radial direction onto the filter element 50. There it flows through the filter element 50 and enters its central drainage pipe 54. On the (preferably left) side of the drain there is an adapter that centers the element. The pressure medium flows on to cross section F, which represents an outlet of the filter element 50 on the bottom. Due to the helical flow, the filter effect is superimposed on a cyclonic separation effect and the separation of impurities is further improved.

The passage area E extends over the entire filter element. The helical shape causes a circulation around this element.

Disclosed is a hydraulic control block for a servohydraulic axis, with im

Control block accommodated filter or filter element or at least with a cavity provided for it.

A servohydraulic axis is also disclosed with it.

Claims

1. Hydraulic control block for a servo-hydraulic axis (1), in particular

Linear axis, at least with hydraulic interfaces to the hydraulic

Connection of a hydraulic actuator (2) of the axis (1), and with a cavity (30) in which a hydraulic machine or at least engine components thereof can be accommodated at least in sections to supply pressure medium to the actuator (2), or with the hydraulic machine flanged or piped is characterized by a preferably second cavity (14) in which a

Filter element (50) for filtering the pressure medium can be received or received at least in sections.

2. Control block according to claim 1, wherein the cavities (14, 30) in one

The direction of extent of the control block (10) are spaced apart and are arranged in a transverse direction (18) with an overlap at least in sections.

3. Control block according to claim 1 or 2 with an outer jacket surface section with an, in particular predominantly constant, offset (d) to the preferably second cavity (14).

4. Control block according to one of claims 1 to 3, which is cast, wherein at least one of the cavities (14, 30) is originally formed and / or drilled by means of a cast core.

5. Control block according to one of the preceding claims with one with the

Hydraulic fluid flow path, in particular an inlet channel (A), which can be or is connected to a hydraulic machine, with an inlet opening (46) in one

Inner jacket surface (38) of the preferably second cavity (14).

6. Control block according to claim 5, wherein the inner lateral surface (38) extends circumferentially around an insertion axis (21) of the preferably second cavity (14) for the filter element (50).

7. Control block according to claim 5 or 6, wherein the pressure medium flow path at least at the inlet opening (46) is tangential to the inner lateral surface (38)

Has directional component.

8. Control block according to one of the preceding claims, wherein a

Inner jacket surface (38) of the preferably second cavity (14) has a recess (52) which extends helically around an insertion axis (21) of the preferably second cavity (14).

9. Control block according to claim 8, wherein the recess (52) consists of an inlet mouth

(46) arises or begins at a distance from this (46).

10. Control block according to claim 8 or 9, wherein the recess (52) extends circumferentially or at least once over the entire circumference of the insertion axis (21).

11. Control block according to one of claims 8 to 10, wherein the recess (52) has a flattened semicircular or elliptical cross-section (C, D).

12. Control block according to one of claims 8 to 11, wherein the recess (52) is a

The ratio of depth to width is between 1:10 and 1: 5, in particular 1: 7.

13. Control block according to at least claim 6, wherein an insertion axis of the first cavity

(30) for the hydraulic machine or the engine components is parallel or one behind the other or in series or transversely or perpendicular to the insertion axis (21) of the second cavity (14) for the filter element (50).

14. Servohydraulic axis with a hydraulic control block (10), which according to

one of the preceding claims, and with an at least hydraulically connected hydraulic actuator (2), one

Hydraulic machine for its pressure medium supply and a filter element (50) for filtering the pressure medium, which is accommodated in the preferably second cavity (14).