阅读说明：本技术 压力调节阀和具有这种用于控制或调节先导压力室中的压力流体的压力的压力调节阀的装置 (Pressure regulating valve and device having such a pressure regulating valve for controlling or regulating the pressure of a pressure fluid in a pilot pressure chamber ) 是由 比约恩·伯格菲尔德 于 2020-01-23 设计创作，主要内容包括：本发明涉及一种用于控制或调节先导压力室(12)中的压力流体的压力的压力调节阀(30),其包括：具有至少一个入口(41)和至少一个出口(43)的阀壳体(50),所述至少一个入口(41)可以与所述先导压力室(12)流体连接；固定布置在所述压力调节阀(30)中的壁部段(51),所述壁部段(51)具有可由所述压力流体流过的贯通通道(60)并且形成第一阀座(58)；柱塞(52),所述柱塞(52)借助可通电的致动装置(49)沿纵向轴线(L)可移动地支承在所述阀壳体(50)中；第一密封元件(54),所述第一密封元件(54)形成第二阀座(66),沿所述纵向轴线(L)可移动地支承在所述阀壳体(50)中,以及借助第一弹簧(56)对着所述致动装置(53)的致动方向(B)被偏置到封闭位置,在所述封闭位置处,所述第一密封元件(54)抵靠所述第一阀座(58)并可通过所述压力流体在致动方向(B)上移动；第二密封元件(64),所述第二密封元件(64)紧固在所述柱塞(52)处,其中,所述第二阀座(66)布置成相对于所述纵向轴线(L)与所述第一阀座(58)轴向错开；以及第二弹簧(68),所述第二弹簧(68)将所述第二密封元件(64)偏置到所述第一位置。(The invention relates to a pressure regulating valve (30) for controlling or regulating the pressure of a pressure fluid in a pilot pressure chamber (12), comprising: a valve housing (50) having at least one inlet (41) and at least one outlet (43), the at least one inlet (41) being fluidly connectable with the pilot pressure chamber (12); a wall section (51) fixedly arranged in the pressure regulating valve (30), the wall section (51) having a through-channel (60) through which the pressure fluid can flow and forming a first valve seat (58); a plunger (52), the plunger (52) being mounted in the valve housing (50) so as to be displaceable along a longitudinal axis (L) by means of an electrically activatable actuating device (49); a first sealing element (54), which first sealing element (54) forms a second valve seat (66), is movably supported in the valve housing (50) along the longitudinal axis (L), and is biased by means of a first spring (56) against an actuation direction (B) of the actuation device (53) into a closed position, in which the first sealing element (54) abuts against the first valve seat (58) and is movable by the pressure fluid in the actuation direction (B); a second sealing element (64), the second sealing element (64) being fastened at the plunger (52), wherein the second valve seat (66) is arranged axially offset from the first valve seat (58) with respect to the longitudinal axis (L); and a second spring (68), the second spring (68) biasing the second sealing element (64) to the first position.)

1. A pressure regulating valve (30) for controlling or regulating the pressure of a pressure fluid in a pilot pressure chamber (12), comprising:

-a valve housing (50) having at least one inlet (41) and at least one outlet (43), the at least one inlet (41) being fluidly connectable with the pilot pressure chamber (12);

-a wall section (51) fixedly arranged in the pressure regulating valve (30), the wall section (51):

has a through channel (60) through which said pressure fluid can flow, and

form a first valve seat (58);

-a plunger (52), which plunger (52) is movably supported in the valve housing (50) along a longitudinal axis (L) by means of an energizable actuating device (49);

-a first sealing element (54), the first sealing element (54) being:

form a second valve seat (66);

-is movably supported in the valve housing (50) along the longitudinal axis (L); and

is biased by means of a first spring (56) against an actuation direction (B) of the actuation device (53) into a closed position in which the first sealing element (54) abuts against the first valve seat (58) and is movable in the actuation direction (B) by the pressure fluid;

-a second sealing element (64), said second sealing element (64) being fastened at said plunger (52) and being movable by energization of said actuating means (49) along said longitudinal axis (L) by means of said plunger (52) between a first position, in which said second sealing element (64) abuts against said wall section (51) and closes said through passage (60), and a second position, in which said second sealing element (64) abuts against a second valve seat (66), wherein said second valve seat (66) is arranged axially offset from said first valve seat (58) with respect to said longitudinal axis (L); and

-a second spring (68), the second spring (68) biasing the second sealing element (64) to the first position.

2. Pressure regulating valve according to claim 1, characterized in that the first sealing element (54) has a first surface (C1) which can be forced by the pressure fluid and directed away from the wall section (51) and a second surface (C2) which can be forced by the pressure fluid and directed towards the wall section (51), wherein the second surface (C2) is larger than the first surface (C1).

3. Pressure regulating valve (30) according to one of the preceding claims, characterized in that the second valve seat (66) is formed by a tube (67) arranged in the first sealing element (54).

4. The pressure-regulating valve (30) of claim 3, wherein the tube (67) is movably connected with the first sealing element (54) along the longitudinal axis (L).

5. The pressure-regulating valve (30) as claimed in any one of the preceding claims, characterized in that the through-channel (60) is formed by an annular gap (62) between the wall section (51) and the plunger (52).

6. The pressure-regulating valve (30) as claimed in one of the preceding claims, characterized in that the wall section (51) has a through-hole (73), the through-hole (73) being flowable by the pressure fluid, and the through-hole (73) being not closable by the first sealing element (54).

7. The pressure-regulating valve (30) as claimed in any one of the preceding claims, characterized in that the cross-sectional area of the through-passage or the annular gap is greater than the cross-sectional area of the throttle gap (74) from the second sealing element (64).

8. The pressure-regulating valve (30) of claim 7, wherein the cross-sectional area (A4) of the annular gap (62) is greater than:

-a first throttle gap (74) formed between the second sealing element (64) and the second valve seat (66) or between the plunger (52) and the valve seat (66)₁) Or is or

-a second throttling gap (74) formed between the second sealing element (64) and the first sealing element₂) Or is or

-a third throttling gap (74) formed between the second sealing element (64) and the wall section₃) Cross-sectional area (a1, a2, A3).

9. The pressure-regulating valve (30) as claimed in one of the preceding claims, characterized in that the pressure-regulating valve (30) is constructed as a proportional valve (75).

10. Pressure regulating valve (30) according to one of the preceding claims, characterized in that the wall section (51) is embodied as a first spring plate (53) and/or the second sealing element (64) is embodied as a second spring plate (72).

11. The pressure-regulating valve (30) as claimed in one of the preceding claims, characterized in that the second sealing element (64) is connected with the plunger (52) by means of a clearance fit.

12. The pressure-regulating valve (30) as claimed in claim 10 or in claims 10 and 11, characterized in that the second spring plate (72) is fitted tightly on the plunger (52).

13. Pressure regulating valve (30) according to one of the preceding claims, characterized in that the actuating means (49) comprise a magnet (44) through which a pressure fluid can flow.

14. A device for controlling and regulating the pressure in a pilot pressure chamber (12), comprising:

-a primary circuit (14) for a pressure fluid;

-a working machine (16) arranged in the primary circuit (14) for conveying the pressure fluid in the primary circuit (14) in a conveying direction;

-a hydraulic or pneumatic slide valve (24);

-a secondary circuit (20) for the pressure fluid,

-the secondary circuit (20) starts from a branch (18) of the primary circuit (14), the branch (18) being arranged downstream of the work machine (16) with respect to the conveying direction; and

-the secondary circuit (20) remits into the primary circuit (14) again in an intake (22);

-a pilot pressure chamber (12) arranged in the secondary circuit (20); and

-a pressure regulating valve (30) according to any one of the preceding claims arranged between the pilot pressure chamber (12) and the junction (22) in the secondary circuit (20), wherein,

-the spool (24) is arranged and designed such that the spool (24) can block or release the flow of the pressure fluid in the primary circuit (14) between the branch (18) and the junction (22) depending on the pressure in the pilot pressure chamber (12).

15. Device according to claim 14, characterized in that the slide valve (24) is designed as a proportional slide valve (26).

16. An arrangement according to any one of claims 14 or 15, characterised in that the actuating means (49) of the pressure regulating valve (30) comprises a magnet (44) through which the pressure fluid can flow, and that the magnet (44) is in fluid connection with the pilot pressure chamber (12) or with an external pressure fluid circuit (46).

17. The arrangement according to any one of claims 14 to 16, characterized in that the working machine (16) is constructed as a pump (78), a compressor (80) or a vibration damper (82).

Technical Field

The present invention relates to a pressure regulating valve for controlling or regulating the pressure of a pressure fluid in a pilot pressure chamber. The invention also relates to a device having such a pressure regulating valve, with which the pressure of the pressure fluid in the pilot pressure chamber can be regulated.

Background

Hydraulic liquid or compressed air is usually used as the pressure fluid. The pilot pressure chamber in the hydraulically or pneumatically operated device serves for controlling or regulating a pilot valve, which is usually also embodied as a hydraulic or pneumatic spool valve. When the pilot valve is designed as a proportional valve or a proportional spool, the volume flow through the proportional valve or the proportional spool can be set steplessly within a certain range with the pressure in the pilot pressure chamber.

An example of such a hydraulically or pneumatically operated device is a shock absorber in a motor vehicle, wherein the damping characteristics depend on the volume flow of the used pressure fluid through the proportional valve. Depending on the volume flow, a more accentuated comfortable, softer damping or a more sportive, harder damping can be set. In the case of a shock absorber, an energizable actuating device is used, with which a plurality of damping characteristics can be specified in advance by the driver or can be set automatically by the on-board computer depending on the driving state of the motor vehicle or the state of the road surface along which the motor vehicle is currently driving. However, it must be ensured that in the event of a failure of the electrical energy and therefore of the actuating means, there is a Failsafe, also referred to as "Failsafe". This ensures that the vehicle can continue to operate with a certain damping behavior even in the event of a power failure. Here, it is generally intended to achieve a moderate damping characteristic that is neither too hard nor too soft.

These requirements result in a relatively complex construction of the device, particularly for the shock absorber, as can be seen for example from US2016/0091044a1 and WO2016/066314a 1. The construction is thereby particularly complicated, since a plurality of slide valves must be used. Further shock absorbers are disclosed in US2016/0369862a1, JP2009-115319a, US5,147,018A, WO2011/023351a1 and US2005/0016086A 1. In particular, the shock absorber disclosed in EP2678581B1 provides moderate damping characteristics even in "fail-safe".

Disclosure of Invention

It is an object of an embodiment of the invention to provide a pressure regulating valve for regulating the pressure of a pressure fluid in a pilot pressure chamber, which is simple in construction and which regulates the pressure in the pilot pressure chamber to a determinable level even when no electrical energy is available for the energization of the actuating means. Furthermore, one embodiment of the invention is based on the object of providing a device with which the pressure of the pressure fluid in the pilot pressure chamber can be regulated and which can be operated using such a pressure regulating valve.

This object is achieved by the features specified in claims 1 and 14. Advantageous embodiments are the subject of the dependent claims.

One embodiment of the present invention relates to a pressure regulating valve for regulating a pressure of a pressure fluid in a pilot pressure chamber, including:

-a valve housing having at least one inlet and at least one outlet, the at least one inlet being fluidly connectable with the pilot pressure chamber;

-a wall section fixedly arranged in the pressure regulating valve, the wall section:

o has a through channel through which said pressure fluid can flow, and

form a first valve seat;

a plunger which is mounted in the valve housing so as to be displaceable along a longitudinal axis by means of an energizable actuating device;

-a first sealing element that:

form a second valve seat;

o is movably supported in the valve housing along the longitudinal axis; and

o is biased by means of a first spring against an actuation direction of the actuation device to a closed position in which the first sealing element abuts against the first valve seat and is movable in an actuation direction by the pressure fluid;

-a second sealing element fastened at the plunger and movable by the plunger along the longitudinal axis by energization of the actuating means between a first position, in which it abuts against the wall section and closes the through passage, and a second position, in which it abuts against a second valve seat, wherein the second valve seat is arranged axially offset from the first valve seat with respect to the longitudinal axis; and

-a second spring biasing the second sealing element to the first position.

The essential characteristic of the proposed pressure regulating valve is that it has at least two valve seats through which pressure fluid can flow when the valve seat in question is open. The pressure regulating valve is designed such that, when at least one of the valve seats is open, pressure fluid can flow through the pressure regulating valve. In this regard, the first and second valve seats are connected in parallel with one another for opening.

While the second valve seat can be opened and closed directly or indirectly as a result of the energization of the actuating device and the resulting movement of the second sealing element, the first valve seat is opened as a result of the pressure acting in the pressure-regulating valve. In other words, the second valve seat is actively opened by energization, while the first valve seat is passively opened due to the prevailing pressure ratio. The second spring ensures that the through-passage is closed in the event of a failure of the actuating device.

This has the result that a flow through the pressure regulating valve is possible even without electrical energy for the energization of the actuating device. Thus, the pressure in the pilot pressure chamber can be controlled or regulated even in the event of a power failure, so that Failsafe, also referred to as "Failsafe", can be provided by only a single pressure regulating valve. The damping characteristics set in the event of a malfunction are determined by the choice of spring constant and spring bias of the first spring.

The pressure regulating valve may also be closed when the second sealing element is in the second position and the second sealing element is against the second valve seat. However, flow through the pressure regulating valve and thus the pressure in the pilot pressure chamber cannot be controlled or regulated, so that the second sealing element is normally not moved into the second position upon operation of the pressure regulating valve.

The first valve seat and the second valve seat are arranged axially offset from one another relative to the longitudinal axis, so that a displaceability of the second sealing element along the longitudinal axis can be ensured. The provision of a second sealing element for throttling enables a very precise setting of the opening point and the desired damping characteristics. In the case of the pressure regulating valve disclosed in EP2678581B1, throttling and opening and closing of the valve seat are performed using a plunger. The pressure regulating valve shown here has no second sealing element. Therefore, the desired damping characteristics cannot be set as accurately as the existing pressure regulating valve. Furthermore, the damping characteristics can be changed using the present pressure regulating valve in a simple manner in that a second sealing element of a different size is used. In the case of the pressure regulating valve disclosed in EP2678581B1, the entire plunger has to be changed for this purpose, which is considerably more complicated.

In contrast to the pressure regulating valve disclosed in EP2678581B1, the proposed pressure regulating valve does not have a movable valve chamber with movable wall sections. More precisely, the wall section is firmly connected to the valve housing. Whereby the damping characteristics can be set more accurately. Furthermore, the support of the movable part is simplified compared to the pressure regulating valve disclosed in EP2678581B 1.

According to a further embodiment, the first sealing element has a first surface which can be forced by the pressure fluid and directed away from the wall section and a second surface which can be forced by the pressure fluid and directed towards the wall section, wherein the second surface is larger than the first surface. For the case that no electrical energy is available for the energization of the actuating means, a second spring is used to move the second sealing element into a first position in which it closes the through-passage. Thus, the pressure fluid does not flow through the through-going passage, thereby creating a pressure upstream of the second sealing element, which pressure acts not only on the first surface of the first sealing element but also on the second surface of the first sealing element. But due to the fact that the second surface is larger than the first surface, the same pressure acts on the first surface and the second surface, the pressure fluid exerting a fluid force on the first sealing element, which fluid force acts in the actuating direction of the actuating means and thus overcomes the biasing force of the first spring. Thus, the first sealing element is moved in the actuating direction until a force equilibrium is established between the biasing force of the first spring and the fluid force applied to the first sealing element by the pressure fluid. The first valve seat is opened so that the pressure fluid can flow through the first valve seat. Thus, the flow through of the pressure regulating valve ("fail-safe") can also be achieved when there is no electrical energy for operating the actuating device.

According to a modified embodiment, the second valve seat is formed by a tube arranged in the first sealing element. In particular, when structural changes are to be made to the pressure regulating valve that require a different positioning of the second valve seat, it is only necessary to change the diameter and/or length of the tube and the corresponding housing of the first sealing element. The valve housing itself can remain unchanged.

According to a further embodiment, the tube is connected to the first sealing element so as to be movable along the longitudinal axis. Here, it is proposed that the tube is connected to the first sealing element by means of a frictional connection, for example by means of a certain excess with respect to the first sealing element, in order to clearly maintain the position of the second valve seat during operation of the pressure regulating valve. However, the position of the second valve seat can be adjusted by using a suitable tool to overcome the frictional connection when installing the pressure regulating valve. This allows the magnetic forces, which may differ due to tolerance differences, to be standardized. The opening point deviating from the nominal value due to manufacturing tolerances can be corrected in a relatively simple manner.

According to another embodiment, the through channel is formed by an annular gap between the wall section and the plunger. In this embodiment, the through-channel can be realized in a structurally simple manner.

According to a further embodiment, the wall section has a through-opening, through which the pressure fluid can flow and which is not closable by the first sealing element. The through hole is used for guiding the pressure fluid downstream of the first valve seat, i.e. after the pressure of the pressure fluid has been set to a desired level. The pressure fluid can thus be guided by means of a pressure control valve having a short path, which requires little structural changes.

According to a further embodiment, the cross-sectional area of the through-passage or the annular gap is greater than the cross-sectional area of the throttle gap from the second sealing element. The aforementioned control or regulation of the pressure in the pilot pressure chamber is mainly performed by throttling the flow of pressure fluid in the pressure regulating valve. The amount of throttling is determined by the minimum passable cross section. When flowing through the pressure regulating valve, the pressure fluid essentially passes through two cross sections, namely on the one hand through the annular gap and on the other hand through the throttle gap formed by the second sealing element or the plunger. Although the annular gap is predetermined in construction and its cross-sectional area cannot be changed, the cross-sectional area of the throttle gap can be changed due to a more or less strong energization of the actuating means. Due to the fact that the cross-sectional area of the throttle gap at each position of the plunger is smaller than the cross-sectional area of the annular gap or the through-passage, it is ensured that the pressure in the pilot pressure chamber can be varied by means of the energization of the actuating means.

According to a further embodiment, the cross-sectional area of the first annular gap and the second annular gap is greater than:

a first throttling gap formed between the second sealing element and the second valve seat, or

A second throttle gap formed between the second sealing element and the first sealing element, or

-a third throttling gap formed between the second sealing element and the wall section

Cross-sectional area of (a).

If the second sealing element is located between the first position and the second position, the pressure fluid is first deflected radially outward, then parallel to the longitudinal axis and then again radially inward, as seen in the flow direction by the second sealing element. If the pressure fluid flows radially outwards, it flows through a first throttle gap extending parallel to the longitudinal axis. The pressure fluid flows through the second throttle gap when flowing parallel to the longitudinal axis, and the pressure fluid flows through the third throttle gap when flowing radially inward. A first throttle gap is formed between the second sealing element and the second valve seat. A second throttle gap is formed between the second sealing element and the first sealing element, and a third throttle gap is formed between the second sealing element and the wall section.

The cross-sections of the first and third throttling gaps vary depending on the position of the second sealing element. The throttling gap with the smallest cross-sectional area shall be referred to as the active throttling gap, since this determines the degree of throttling of the pressure fluid flow. The pressure regulating valve is designed such that, independently of the position of the plunger, the cross-sectional area of the annular gap is greater than the cross-sectional area of the active throttle gap. As a result, it is ensured that the pressure in the pilot pressure chamber can be changed by means of the energization of the actuating means.

According to a further embodiment, the pressure regulating valve is designed as a proportional valve. In this embodiment, the volume flow through the pressure regulating valve can be regulated in the following manner: as mentioned above, the second sealing element may be reciprocally movable between the first position and the second position by means of the actuating means. The proportional valve is designed such that the throttle gap and thus also the volume flow vary linearly. Thus, the pressure in the pilot pressure chamber may be controlled in proportion to the energization of the actuation means.

In a further embodiment, the wall section is embodied as a first spring plate and/or the second sealing element is embodied as a second spring plate. The wall section and the second sealing element are sufficiently stable in this embodiment, on the one hand, with a small wall thickness, and on the other hand are relatively easy to manufacture.

According to a further embodiment, the second sealing element is connected to the plunger by means of a clearance fit. Tolerances can thereby be compensated in a simple manner.

An improved embodiment is characterized in that the spring plate is fitted tightly on the plunger. In this way, a sufficient fastening of the spring plate at the plunger can be achieved in a simple manner.

According to another embodiment, the actuating means comprise a magnet through which the pressure fluid can flow. Actuating devices that use magnets to move a plunger are common, and thus may be used in the manufacture of the present pressure regulator valve. However, when the magnet can be flowed through by a pressure fluid, the advantage arises that the pressure fluid acts as a coolant, since it can conduct away at least a part of the heat generated in the operation of the magnet from the magnet. Thereby reducing the thermal load on the magnet and improving its durability.

One embodiment of the invention relates to a device for controlling and regulating the pressure in a pilot pressure chamber, comprising:

-a primary circuit for a pressure fluid;

-a working machine arranged in the primary circuit for conveying the pressure fluid in the primary circuit in a conveying direction;

-a hydraulic or pneumatic slide valve;

-a secondary circuit for the pressure fluid,

-the secondary circuit starts from a branch of the primary circuit, which branch is arranged downstream of the working machine with respect to the conveying direction; and

o said secondary circuit merging again into said primary circuit in a merging mouth;

-a pilot pressure chamber arranged in the secondary circuit; and

-a pressure regulating valve according to any one of the preceding embodiments arranged between the pilot pressure chamber and the junction opening in the secondary circuit, wherein,

the spool is arranged and designed such that it can block or release the flow of the pressure fluid in the primary circuit between the branch and the junction depending on the pressure in the pilot pressure chamber.

The advantages and technical effects that can be achieved with the proposed device correspond to those already explained with the pressure regulating valve according to one of the previously discussed embodiments. In summary, it should be pointed out that only one pressure regulating valve and only one spool are required for the active and passive regulation of the pressure in the pilot pressure chamber, and that the constructional expenditure of the device can be kept low.

According to a further embodiment, the slide valve is designed as a proportional slide valve. The spool valve blocks the primary circuit between the branch and the discharge opening in the closed position as a function of the pressure in the pilot pressure chamber. In this case, the pressure fluid can only flow from the branch to the outlet via the secondary circuit. As soon as the pressure in the pilot pressure chamber is exceeded or undershot, depending on the design of the device, the spool is moved into the open position, so that fluid can also flow in the primary circuit between the branch and the outlet opening. However, a simple spool valve can only move between an open position or a closed position, so that the flow of pressure fluid in the primary circuit between the branch and the junction can be completely released or blocked. However, when the spool is designed as a proportional spool, the volume flow of the pressure fluid in the primary circuit between the branch and the discharge opening can be set as a function of the pressure in the pilot pressure chamber. Since the pressure in the pilot pressure chamber can again be set by the energization of the actuating device, the volume flow of the pressure fluid in the primary circuit between the branch and the discharge opening can also be set by the energization of the actuating device, while a failsafe can be achieved in the event of a failure of the actuating device.

A further embodiment is characterized in that the actuating device of the pressure regulating valve comprises a magnet through which the pressure fluid can flow, and the magnet is in fluid connection with the pilot pressure chamber or with an external pressure fluid circuit. As described above, an actuating device using a magnet to move a plunger is common, so that such an actuating device can be used. However, when the magnet can be flowed through by a pressure fluid, the advantage arises that the pressure fluid acts as a coolant, since it can conduct away at least a part of the heat generated in the operation of the magnet from the magnet. Thereby reducing the thermal load on the magnet and improving its durability.

When the magnet is in fluid connection with the pilot pressure chamber, the pressure prevailing there can be used as a delivery pressure for the pressure fluid, so that no further delivery elements have to be used. The structure of the device is not significantly complicated. In the case of a magnet which is in fluid connection with the external pressure fluid circuit, the volume flow through the magnet can be varied independently of the volume flow and the pressure ratio in the secondary circuit.

A further embodiment is characterized in that the working machine is designed as a pump, a compressor or a vibration damper. The damper can be designed as a two-tube or three-tube damper. Due to the regulation in the pilot pressure chamber, such a working machine can be controlled or regulated particularly well in a simple manner by means of the proposed device. In the case of a working machine designed as a vibration damper, the damping characteristics can be set by energizing the drive in such a way that a harder or softer damping results. Damping, which is dependent on the spring bias and the spring constant of the first spring, can also be ensured in the event of a failure of the actuating means.

Drawings

Fig. 1 shows a circuit diagram of an embodiment of the proposed device for controlling or regulating the pressure of a pressure fluid in a pilot pressure chamber;

fig. 2A shows a cross-sectional view of an embodiment of the proposed pressure regulating valve;

FIG. 2B shows an enlarged view of section X marked in FIG. 2A;

FIG. 2C shows a separate illustration of the first sealing element;

FIG. 3A shows a basic and not to scale enlarged view of section X marked in FIG. 2A, with the pressure regulating valve in a first operating state;

FIG. 3B shows a basic, not to scale, view of section X labeled in FIG. A2 with the pressure regulator valve in a second operational state; and

fig. 3C shows a basic and not-to-scale enlarged view of the section X marked in fig. 2A, with the pressure regulating valve in a third operating state.

Detailed Description

Fig. 1 shows a circuit diagram of a device 10 for controlling or regulating the pressure of a pressure fluid in a pilot pressure chamber 12. Hydraulic liquid or compressed air can be used as pressure fluid, wherein the following description relates to pressure fluid designed as hydraulic liquid. The arrangement 10 comprises a primary circuit 14, in which primary circuit 14 pressure fluid can be conveyed by means of a working machine 16. A working machine 16 is to be understood as a component with which mechanical work can be transmitted in particular to a pressure fluid in such a way that it is conveyed in the primary circuit 14 in a conveying direction indicated by an arrow P1.

With regard to the conveying direction indicated by the arrow P1, a branch 18 is arranged downstream of the working machine 16, from which branch 18a secondary circuit 20 is started, which secondary circuit 20 can also be flowed through by pressure fluid. The exact design of the secondary loop 20 will be discussed in more detail later.

Downstream of the branch 18, a junction 22 is provided in the primary circuit 14, at which junction 22 the secondary circuit 20 again joins the primary circuit 14. In the example shown, the discharge opening 22 is realized by means of a low-pressure chamber 23.

Starting from the low-pressure chamber 23, the primary circuit 14 opens again into the working machine 16.

As can be seen from fig. 1, downstream of the branch 18, a slide valve 24 is arranged, which slide valve 24 is embodied in the exemplary embodiment shown as a proportional slide valve 26, which proportional slide valve 26 interacts with a spring 25. The secondary circuit 20 is not blocked by the spool valve 24. The spool valve 24 is adjustable between two positions, wherein in the first position shown in fig. 1, the spool valve 24 blocks the primary circuit 14 between the branch 18 and the sink 22. And in the second position, there is a fluid connection between branch 18 and inlet 22 in primary circuit 14. The slide valve 24 is embodied as an 2/2 valve.

The spring 25 interacts with the slide valve 24 in such a way that the slide valve 24 is biased into the first position. A first control line 27 leads out between the work machine 12 and the branch 18, which first control line 27 is connected to the slide valve 24. Furthermore, a second control line 29 leads from the pilot pressure chamber, which second control line 29 is also connected to the slide valve 24, as is the first control line 27. The pressure fluid led to the spool 24 via the first control line 27 acts on the spool 24 in the opposite direction compared to the pressure fluid led to the spool 24 via the second control line 29. The pressure fluid led to the spool 24 via the second control line 29 acts in the same direction as the spring 25.

Starting from branch 18, a main orifice plate 28 is arranged in secondary circuit 20 downstream of spool valve 24. The secondary circuit 20 then opens into the already mentioned pilot pressure chamber 12. Starting from the pilot pressure chamber 12, downstream of the pilot pressure chamber 12, a pressure regulating valve 30 is arranged, the function of which can be understood as a magnetically controlled 3/2 valve and a purely hydraulically controlled 3/2 valve connected in parallel thereto. The exact structural design of the pressure regulating valve 30 will be discussed in more detail later.

Downstream of the pressure regulating valve 30, the first line 32 runs directly to the low-pressure chamber 23, while the second line 34 branches into a first sub-line 36 and a second sub-line 38, wherein a check valve 40 is arranged in the first sub-line 36 and an auxiliary orifice 42 is arranged in the second sub-line 38. The check valve 40 and the auxiliary orifice plate 42 are connected in parallel with each other. Downstream of the check valve 40 and the auxiliary orifice 42, the first sub-line 36 and the second sub-line 38 merge again. From there, the second line 34 leads, like the first line 32, to the low-pressure chamber 23. As described above, the secondary circuit 20 merges into the primary circuit 14 again in the low-pressure chamber 23.

As already mentioned, the proposed pressure regulating valve 30 can be understood from its function as a magnetically controlled 3/2 valve and a pressure control 3/2 valve connected in parallel thereto, which in the example shown comprises one inlet 41 and two outlets 43. As will be apparent from the description below, the pressure regulating valve 30 may operate as an 3/3 valve. However, the pressure regulating valve 30 can also be designed such that it can be understood from its function as a magnetically controlled 2/2 valve and a pressure control 2/2 valve connected in parallel thereto. In this case, the pressure regulating valve 30 has one inlet 41 and only one outlet 43. Instead of the first line 32 and the second line 34, only one common line (not shown) is present.

The magnetic control valve has a magnet 44, which magnet 44 in the example shown can be flowed through by a pressure fluid, in this case a hydraulic fluid. However, it is also possible to embody the magnet 44 such that it is not flowable. In the embodiment shown in fig. 1, the magnet 44 is connected to an external pressure fluid circuit 46, which external pressure fluid circuit 46 has a delivery pump 48 for delivering pressure fluid in the external pressure fluid circuit 46. One embodiment is not shown in which magnets 44 are fluidly connected to primary loop 14 and/or secondary loop 20. For example, magnet 44 may be fluidly connected to pilot pressure chamber 12 and low pressure chamber 23.

Fig. 2A shows an embodiment of the proposed pressure control valve 30 in a sectional view. The section X marked in fig. 2A is shown enlarged in fig. 2B and 3A. Therefore, the following description refers not only to fig. 2A, but also to fig. 2B and 3A. For better understanding, the pilot pressure chamber 12 and the low pressure chamber 23 are also shown in fig. 2A and 3A.

The pressure regulating valve 30 comprises a valve housing 50, in which valve housing 50 the already mentioned slide valve 24 is arranged in the region on the left with respect to the illustration selected in fig. 2A. In addition, primary circuit 14 is shown in fig. 2A, and primary circuit 14 may be opened or closed with spool valve 24.

The pressure regulating valve 30 further comprises a plunger 52, which plunger 52 is mounted displaceably in the valve housing 50 along the longitudinal axis L and is displaceable in the displacement direction B by means of an energizable actuating device 53. The direction of movement B extends parallel to the longitudinal axis L. In the following, the valve housing 50 is to be understood as all components which form the wall and the cavity of the pressure regulating valve 30 in any way. Here, the valve housing 50 may have a plurality of such members.

Furthermore, a wall section 51 is fixedly arranged in the pressure regulating valve 30, which wall section 51 forms a through-channel 60 (fig. 3A), through-channel 60 being flowable by the pressure fluid and being embodied as an annular gap 62. An annular gap 62 is formed between the wall section 51 and the plunger 52. The wall section 51 also forms a first valve seat 58 and is designed in the embodiment shown as a first spring plate 53. Furthermore, the wall section 51 has at least one through hole 73, which will be discussed in more detail later.

The pressure regulating valve 30 shown in fig. 2A to 2C has a first sealing element 54 according to a first embodiment₁The first sealing element 54₁Also movably supported in the valve housing 50 along the longitudinal axis L. First sealing element 54₁By means of the first spring 56 is biased against a first valve seat 58 (see fig. 3A), which first valve seat 58 is formed by the wall section 51 firmly connected with the valve housing 50.

The proposed pressure regulating valve 30 further comprises a second sealing element 64 (see fig. 2B and 3A), which second sealing element 64 is fastened at the plunger 52 and is displaceable with the plunger 52 along the longitudinal axis L between a first position, in which the second sealing element 64 abuts against the wall section 51 and closes the through-passage 60 (fig. 2B and 3A), and a second position, in which the second sealing element 64 abuts against a second valve seat 66 (not shown). As can be seen in particular from fig. 2C, the second valve seat 66 is formed by the first sealing element 54 according to the first embodiment₁And (4) forming. The first sealing element 54 is shown in fig. 3A to 3C₂The first sealing element 54₂With the first sealing member 54 according to the first embodiment₁In particular, the second valve seat 66 is formed by a tube 67, which tube 67 forms a frictional connection with the first sealing element 54₂And (4) connecting. Thus, when a sufficiently large force is applied to the tube 67, the tube 67 may move along the longitudinal axis L. If the pipe 67 is displaced, the position of the second valve seat 66 is also changed, so that the opening point of the pressure regulating valve 30 can be changed in a simple manner.

As can be seen in FIG. 3A, tube 67 has an inner diameter D_RIAnd an outer diameter D_RA. Furthermore, the plunger 52 has an outer diameter D at the end pointing towards the tube 67_sA. In the illustrated embodiment of the pressure regulating valve 30, the outer diameter D of the plunger 52_sASmaller than the inner diameter D of the tube 67_RI. Not shown is an embodiment wherein the outer diameter D of the plunger 52_SAGreater than the internal diameter D of the tube 67_RIBut less than the outer diameter D of the tube 67_RA。

The pressure regulating valve 30 further comprises a second spring 68 (see fig. 2A), which second spring 68 interacts with the plunger 52 in such a way that the second sealing element 64 is biased into the first position and thus pressed against the wall section 51. In this respect, the wall section 51 forms a third valve seat 70 for the second sealing element 64.

The second sealing element 64 is embodied as a second spring plate 72, which second spring plate 72 is fastened to the plunger 52 by means of a clearance fit. The clearance fit is implemented such that the spring plate 72 can be moved to a minimum not only along the longitudinal axis L but also perpendicular thereto. The fastening can be performed by end-side caulking of the plunger 52. The spring plate 72 has a thickness of 0.1mm to 0.5 mm.

In fig. 2A, 2B and 3A, the pressure regulating valve 30 is in a first operating state, while the pressure regulating valve 30 in fig. 3B and 3C, which similarly show the section X marked in fig. 2, is in a second or third operating state.

In FIG. 3A, the device 10 is in a non-pressurized state with the first sealing element 54₂The wall section 51 and the first valve seat 58 are pressed by means of the first spring 56, and the second sealing element 64 is pressed by means of the second spring 68 against the wall section 51 and the third valve seat 70. Therefore, the pressure fluid does not flow through the pressure regulating valve 30, and the second valve seat 66 is also indirectly closed. The through hole 73 is located radially outside the first valve seat 58, so that the through hole 73 is not closed by the first sealing member 58.

In fig. 3B, the pressure regulating valve 30 is in a second operating state, which corresponds to the intended operation of the pressure regulating valve 30. Due to the energization of the actuating device 49, the plunger 52 is displaced in an actuating direction B which is directed leftwards with respect to fig. 2 to 3C and extends parallel to the longitudinal axis, as a result of which the second sealing element 64 is moved away from the wall section 51 and the third valve seat 70 and therefore no longer closes the through-passage 60. The pressure fluid delivered by the work machine 16 via the secondary circuit 20 can therefore flow through the pressure regulating valve 30 as indicated by arrow P2 in fig. 3B and thus reach the low-pressure chamber 23. Here, the pressure fluid flows through the already mentioned through hole 73 and the through hole 84 arranged in the housing 50.

When entering the pressure control valve 30 and after flowing past the second valve seat 66, starting from a flow oriented parallel to the longitudinal axis L, the pressure fluid is first deflected radially outward by the second sealing element 64, wherein it must flow past the first throttle gap 74₁. The pressure fluid is then deflected such that it flows substantially parallel to the longitudinal axis L, wherein it must flow through the second throttle gap 74₂. Thereafter, the pressure fluid is deflected radially inward such that it flows through the third throttle gap 74 before it enters the through-channel 60 with a flow oriented substantially parallel to the longitudinal axis L₃. After the pressure fluid has flowed through the through-passage 60 and the through-holes 73 and 84, the pressure fluid reaches the low-pressure chamber 23.

Outer diameter D of plunger 52_SASmaller than the inner diameter D of the tube 67_RI. Therefore, the first throttle gap 74 is formed starting from the second sealing element 64₁. In one embodiment, not shown, first throttle gap 74₁Starting from the plunger 52, in this embodiment the plunger 52 has an outer diameter D at the end directed towards the tube 67_sAGreater than the internal diameter D of the tube 67_RIBut less than the outer diameter DR of the tube 67_A。

Second throttle gap 74₂And a third restriction gap 74₃Starting with the second sealing element 64. Here, the first throttle gap 74₁Has a first cross-sectional area a1 extending substantially parallel to the longitudinal axis L and is defined between the second seat 66 and the plunger 52. Second throttle gap 74₂A second cross-sectional area A2 extending substantially perpendicular to the longitudinal axis L is formed, the second cross-sectional area A2 being between the second seal member 64 and the first seal member 54₂Extending therebetween. Third throttle gap 74₃Having a third cross-sectional area A3 running substantially parallel to the longitudinal axis L, which third cross-sectional area A3 is formed between the second sealing element 64 and the wall section 51 and in particular the third valve seat 70.

As can be seen from a comparison of fig. 3A and 3B, the third cross-sectional area a3 is equal to zero before energization begins, and thus the through passage 60 is closed. If the energization is now started, the plunger 52 together with the second sealing element 64 is moved away from the wall section 51 and towards the second valve seat 66 in the actuating direction B. This results in an increase in the third cross-sectional area A3 and a decrease in the first cross-sectional area A1. Independently thereof, the second cross-sectional area a2 remains constant. Independent of the dimensions of the first cross-sectional area a1, the second cross-sectional area a2, and the third cross-sectional area A3, the cross-sectional area a4 of the through channel 60 is selected such that it is always greater than at least one of the first, second, and third cross-sectional areas a1, a2, A3.

For reasons of adjustability, it has proven advantageous to use the first throttle gap 74₁Throttling is performed. The energization of the actuating device 49 therefore takes place in such a way that the second sealing element 64 moves together with the plunger 52 as quickly as possible into the middle beyond the distance between the third valve seat 70 and the second valve seat 66. This may be achieved by an initial peak current. Once the second sealing element 64 is located midway to the left between the third valve seat 70 and the second valve seat 66 relative to the views in fig. 2A-3B, the first throttling clearance 74₁Is the smallest of the first, second and third cross-sectional areas a1, a2, A3, so that the throttling of the pressure fluid is performed by the first throttling gap 74₁And (6) determining.

Through the flow, the pressure fluid is throttled, wherein the throttling is determined by a throttle gap 74 having a minimum cross-sectional area a. The pressure in the pilot pressure chamber 12 also changes according to the degree to which the pressure fluid is throttled when flowing through the pressure regulating valve 301. The more throttling, the more the pressure in the pilot pressure chamber 12 increases. The throttling can be performed steplessly and depends on the strength of the current supply to the actuating device 53. Since the volume flow through the pressure control valve 30 is also influenced by the throttling and can be adjusted steplessly, the pressure control valve 30 is designed as a proportional valve 75.

Referring to fig. 1, the effect of the pressure in the pilot pressure chamber 12 on the spool 24 will now be explained. For the case where the pressure in the pilot pressure chamber 12 is greater than or equal to the pressure upstream of the spool 24 in the primary circuit 14, the spool 24 remains in the position shown in fig. 1, so that the primary circuit 14 is blocked between the branch 18 and the sink 22. The fluid connection between branch 18 and intake 22 is provided only by secondary loop 20. However, to facilitate opening of the spool valve 24, a main orifice plate 28 is provided in the secondary circuit 20 downstream of the spool valve 24, which main orifice plate 28 causes the pressure in the secondary circuit 20 downstream of the spool valve 24 to drop at least slightly. If the pressure in the pilot pressure chamber 12 also drops as a result of the above-described energization of the actuating device 53 and the resulting throttling of the pressure fluid, the spool 24 can open and release the primary circuit 14 between the branch 18 and the sink 18. As mentioned above, the spool 24 is designed as a proportional spool 26, which means that the spool 24 releases the primary circuit 14 between the branch 18 and the discharge opening 22 to a greater or lesser extent depending on the pressure in the pilot pressure chamber 12. The volume flow between the branch 18 and the discharge opening 22 can therefore be set by energizing the actuating device 53 in proportion to the pressure in the pilot pressure chamber 12.

In fig. 3C, a third operating state of the pressure regulating valve 30 is shown, in which no electrical energy is available for the energization of the actuating device 49. In this case, the second spring 68 (see fig. 2) puts the second sealing element 64 back into the first position again, in which the second sealing element 64 abuts against the third valve seat 70 and closes the first through passage 53. This intermediate position is equivalent to the first operating state shown in fig. 3A.

As can be seen in particular from fig. 2B and 2C, the first sealing element 54 according to the first embodiment₁Having a first surface C1 which can be forced by the pressure fluid and directed away from the wall section 51 and a second surface C2 which can be forced by the pressure fluid and directed towards the wall section 51. Here, the second surface C2 is larger than the first surface C1. The forces acting on the first sealing means 541 due to the pressure emanating from the pressure fluid are not equal due to the different sizes of the surfaces C1, C2, and a resultant force directed in the actuation direction B is established, whereby the first sealing element 54₁Moving in the actuation direction B. Here, the first spring 56 is compressed until a force equilibrium is reached between the resultant force and the biasing force of the spring 56. This state is shown in fig. 3C. It should be noted that the first sealing member 54 according to the first embodiment₁In the first surface C1 and the second surface C2First sealing element 54 of the two embodiments₂There is no difference.

Thus, the first sealing element 54₂Moving away from the first valve seat 58, thereby opening a gap 76 between the wall section 51 and the first sealing element 542, through which gap 76 pressure fluid can flow and thus reach the low-pressure chamber 23 (arrow P3). Depending on which cross-sectional area a the gap 76 has, the pressure fluid is more or less strongly throttled when flowing through the pressure regulating valve 30. The size of the cross-sectional area a of the gap 76 may be set using the spring bias and spring constant of the first spring 56. Thus, even if the actuating device 49 fails, it is ensured that the spool 24 opens and releases the primary circuit 14 between the branch 18 and the inlet 22. As mentioned above, the degree to which the spool valve 24 is opened depends on the strength of the throttling. Thus, in the event of a failure of the electrical power supply to the actuation device 49, the spring bias and spring constant of the first spring 56 may be used to select the time and degree of opening of the spool valve 24 ("fail safe").

From the foregoing, it can be seen that the pressure regulating valve 30 according to the present invention may operate as an 3/3 valve.

As mentioned above, the second line 34 of the secondary circuit is divided into a first sub-line 36 and a second sub-line 38 (see fig. 1). The switched auxiliary orifice plate 42 and check valve 40 disposed therein ensure shock absorption of the entire device 10 by capturing pressure spikes.

Finally, it should be noted that work machine 16 may be configured as a pump 78, a compressor 80, or a shock absorber 82 of a motor vehicle. In particular, where the work machine 16 is configured as a shock absorber 82, it may be desirable to provide hydraulic synchronization such that fluid is always delivered through the primary circuit 14 and the secondary circuit 20 in the direction shown in fig. 1, independent of the direction of loading of the shock absorber 82. Here, the device 10 according to the invention can be used for a two-tube or three-tube shock absorber 82.

Description of reference numerals:

10 device

12 pilot pressure chamber

14 primary circuit

16 work machine

18 branches

20 secondary circuit

22 sink inlet

23 low pressure chamber

24 spool valve

25 spring

26 ratio slide valve

27 first control line

28 Main orifice plate

29 second control line

30 pressure regulating valve

32 first pipeline

34 second pipeline

36 first sub-pipeline

38 second sub-line

40 check valve

41 inlet

42 auxiliary orifice plate

43 outlet port

44 magnet

46 external pressure fluid circuit

48 transfer pump

49 actuating device

50 valve housing

51 wall section

52 plunger

53 first spring plate

54 first sealing element

54₁，54₂First sealing element

56 first spring

58 first valve seat

60 through passage

62 annular gap

64 second sealing element

66 second valve seat

67 pipe

68 second spring

70 third valve seat

72 second spring plate

74 throttle gap

74₁-74₃First to third throttling gaps

75 proportional valve

76 gap

77 groove

78 Pump

80 compressor

82 shock absorber

84 through hole

Cross sectional area A

A1-A4 first to fourth cross-sectional areas

B direction of actuation

C1 first surface

Second surface of C2

D_RAOuter diameter of pipe

D_RIInner diameter of tube

D_SAInner diameter of plunger

L longitudinal axis

P1-P3 arrow