Pressure control valve

Abstract

The invention relates to a pressure control valve having a control element that includes a valve component and a drive component. The valve component includes an orifice that, in a first position, may be closed by the control element, disconnecting a control chamber from a return chamber, such that a control pressure acts on a first control surface of the control element and in a second position, the orifice may be partially opened, so that the control and return chambers are fluidically connected to each other, such that the control pressure in the control chamber acts on a second control surface of the control element.

Claims

1. A pressure control valve, comprising: a valve component comprising: a control chamber having a control pressure, a return chamber having a return pressure, an orifice extending solely between the control chamber and the return chamber and having a longitudinal axis and comprising at least a first orifice region in a direction of the longitudinal axis and a second orifice region in the direction of the longitudinal axis, the orifice regions spaced apart from each other and having different respective cross-sectional areas, a control element comprising at least a first control element region, including a first control surface, and a second control element region, including a second control surface, the control element regions spaced apart from each other in the direction of the longitudinal axis and having different respective cross-sectional areas, such that the second control surface is larger than the first control surface, wherein the first control surface protruding into the orifice cooperates with the first orifice region to close the orifice, thereby preventing flow between the control chamber and the return chamber, and the second control surface cooperates with the second orifice region to control pressure between the control chamber and the return chamber, and a drive component for the control element, wherein, during operation of the control valve, the first control surface and a surface of the first orifice region remain parallel to each other, and the second control surface and a surface of the second orifice region remain parallel to each other.

2. The pressure control valve of claim 1, wherein, depending on the position of the drive component and the control element operatively connected to the drive component, the orifice is at least one of closed by the drive component and at least partially open for pressure control purposes.

3. The pressure control valve of claim 1, wherein a section having a uniform cross-sectional area is situated between the first and second control surfaces.

4. The pressure control valve of claim 1, wherein a control surface spacing between the first control surface and the second control surface is greater than an orifice region spacing between the first orifice region and the second orifice region.

5. The pressure control valve of claim 1, wherein at least one orifice region is embodied as at least one of a disk-shaped seat and a flat seat.

6. The pressure control valve of claim 1, wherein at least one control surface is embodied as a valve disk.

7. The pressure control valve of claim 1, wherein at least one of an internal width of the second orifice region and a diameter of the second orifice region forms a ratio of at least 1.4 with at least one of a respective internal width of the first orifice region and a diameter of the first orifice region.

8. The pressure control valve of claim 1, wherein the valve component is selected from the group consisting of: metal, steel, brass, and plastic.

9. The pressure control valve of claim 1, wherein the valve component has another sub-valve, which, in a closed position, disconnects the control chamber from a connection.

10. An electromagnetically actuated pressure control valve comprising the pressure control valve of claim 1, wherein the drive component is an electromagnet, whose armature rod is at least one of connected to and operatively connected to the control element.

11. The pressure control valve of claim 1, wherein a section having a uniform cross-sectional area is situated between the first and second orifice regions.

12. The pressure control valve of claim 1, wherein the first and second control surface adjoin each other and are characterized by an abrupt, discontinuous change in the cross-sectional area.

13. The pressure control valve of claim 1, wherein the first and second orifice regions adjoin each other and are characterized by an abrupt, discontinuous change in the cross-sectional area.

14. The pressure control valve of claim 1, wherein at least one orifice region is embodied as a conical seat.

15. The pressure control valve of claim 1, wherein the pressure control valve generates a progressive pressure control characteristic curve during operation.

16. The pressure control valve of claim 4, wherein a ratio of the control element region spacing to the orifice region spacing is between 1 and 3.

17. The pressure control valve of claim 16, wherein the ratio of the control element region spacing to the orifice region spacing is between 1 and 2.

18. The pressure control valve of claim 16, wherein the ratio of the control element region spacing to the orifice region spacing is between 1.2 and 1.4.

19. The pressure control valve of claim 5, wherein another of the at least one orifice regions is embodied as a conical seat.

20. The pressure control valve of claim 6, wherein another of the control surfaces is embodied as at least one of a valve cone and a truncated valve cone.

21. A pressure control valve, comprising: a valve component comprising: a control chamber having a control pressure, a return chamber having a return pressure, an orifice extending solely between the control chamber and the return chamber and having a longitudinal axis and comprising at least a first orifice region in a direction of the longitudinal axis and a second orifice region in the direction of the longitudinal axis, the orifice regions spaced apart from each other and having different respective cross-sectional areas, a control element comprising at least a first control element region, including a first control surface, and a second control element region, including a second control surface, the control element regions spaced apart from each other in the direction of the longitudinal axis and having different respective cross-sectional areas, such that the second control surface is larger than the first control surface, wherein the first control surface protruding into the orifice cooperates with the first orifice region to close the orifice, thereby preventing flow between the control chamber and the return chamber, and the second control surface cooperates with the second orifice region to control pressure between the control chamber and the return chamber, and a drive component for the control element, wherein during operation of the control valve, the control pressure is greater than or equal to the return pressure, and (i) in a first position, the orifice is closed by the control element, such that the first control surface and a surface of the first orifice region remain parallel to each other, preventing fluid communication between the control chamber and the return chamber and the control pressure acts on the first control surface, and (ii) in a second, controlled position, the orifice is partially open, such that the second control surface and a surface of the second orifice region remain parallel to each other, the control chamber and the return chamber are in fluid communication, and the control pressure acts on the second control surface, such that a distance between the first control surface and the second control surface is greater than a distance between the first orifice region and the second orifice region.

Description

DESCRIPTION OF DRAWINGS

(1) The drawings schematically depict the invention and in particular an exemplary embodiment thereof. In the drawings:

(2) FIGS. 1a and 2a each show a sectional depiction of a different exemplary embodiment of the pressure control valve according to the invention,

(3) FIGS. 1b and 2b each show an enlarged view of a detail of the pressure control valve according to the invention from FIGS. 1a and 2a, respectively, and

(4) FIG. 3 shows the control pressure/current characteristic curve of the electromagnetically actuated pressure control valve according to the invention.

DETAILED DESCRIPTION

(5) In the drawings, elements that are the same or that correspond to one another are respectively labeled with the same reference numerals and are thus not described again, where advisable. The basic design of the pressure control valve according to the invention 1 is in particular shown in FIGS. 1a and 2a.

(6) The pressure control valve 1 is composed of a valve component I and a drive component II. The drive component II is used to move the control element 2 of the valve component I.

(7) The drive component II is for example embodied in the form of an electromagnet, resulting in the electromagnetically actuated pressure control valve 1 that likewise falls within the scope of the invention.

(8) The electromagnet 6 that constitutes the drive component II in this exemplary embodiment is depicted only partially in FIGS. 1a and 2a and has a typical design such that in an armature chamber, an armature, which is composed of magnetizable material, is supported so that it can be moved by an electromagnetic field, which can be produced by a coil, preferably in opposition to the force of a return spring. The electromagnet 6 is delimited by a magnet core 61, which in particular serves to guide the magnetic field.

(9) In this case, the armature rod 60 is either connected to the armature or is operatively connected to it so that the movement of the armature is reliably transmitted to the armature rod 60.

(10) The same is also true for the connection of the armature rod 60 to the control element 2. The arrangement is selected so that the magnet core 61, which is part of the electromagnet 6, has a through opening 62 through which the armature rod 60 extends out from the magnet core 61 in a downward direction in the exemplary embodiment shown here and protrudes into the valve component I of the pressure control valve 1.

(11) In particular, the armature rod 60 is supported in the through opening 62 of the magnet core 61, in particular, is supported to permit an axial movement.

(12) At its end oriented away from the electromagnet 6, the armature rod 60 is connected to or operatively connected to the control element 2, which is a component of the valve component I; instead of a rigid connection, this can, for example, be implemented in the form of a loose, but for example spring-loaded connection. Both of the variants mentioned above fall within the scope of the invention.

(13) The pressure control valve 1 in the exemplary embodiment shown in FIG. 1a or 2a has a two-stage design in its valve component I. At the connection 12, the medium to be controlled or regulated—usually a liquid such as hydraulic fluid or the like—is supplied at a connection pressure p1. The connection 12 is restricted or limited in the flow direction of the medium from the sub-valve 5. The sub-valve 5 in this case is composed of a sub-valve orifice 50, which is embodied as a through bore, and a closure element 51, which closes or opens the sub-valve orifice 50 and in the embodiment shown here, is embodied in the form of a closing ball.

(14) The arrangement here is selected so that the closure element 51 in the connection 12 is pressed against the seat of the sub-valve orifice 50 by the connection pressure p1 and an action in opposition to the closing force that results from this must be exerted in order to lift it away from the seat of the sub-valve orifice 50. This opening force is transmitted by a slider 63, which on the end oriented away from the connection 12—viewed in the flow direction S—or in the adjoining control chamber 10, is guided to the sub-valve orifice 50, protrudes through it, and is thus able to act on the closure element 51.

(15) The slider 63 here is operatively connected to the drive component II, for example the electromagnet 6. For example, it is embodied of one piece with the armature rod 60, without restricting the invention to such an embodiment; it is also possible to provide a separate drive for the slider 63, although the integrated embodiment of the slider 63 in the armature rod 60 predetermines a mechanically coupled position, which significantly facilitates the control and regulation of the pressure control valve as a whole.

(16) The sub-valve 5 is then closed when the slider 63 no longer acts on the closure element 51 so that the latter is lifted away from the seat of the sub-valve orifice 50. This position results in the fact that the control element 2 in turn is spaced apart from the orifice 4 so that this control valve 3 is opened.

(17) In the closed position of the sub-valve 5, the closure element 51 is pressed against the sub-valve orifice 50 because of the connection pressure p1 that prevails in the connection 12.

(18) In the flow direction S, the control chamber 10 is connected downstream of the connection 12 and downstream of the sub-valve 5 and its sub-valve orifice 50.

(19) The control chamber 10 is fluidically connected to the component to be controlled, for example to the clutch of an automatic transmission.

(20) In the control chamber 10, the control pressure p2 prevails, which occurs due to the position of the control element 2 relative to the orifice 4 of the second sub-valve component in the flow direction S, described here as the control valve 3.

(21) The control valve 3 is composed of an orifice 4, which is rigidly mounted or stationary in the pressure control valve 1, and the control element 2, which can be positioned relative to the orifice 4 in accordance with the position of the armature rod 60 and/or the drive component II and thus permits a variable pressure divider to adjust or regulate the control pressure p2.

(22) In the exemplary embodiment shown here, the slider 63, which is used to actuate the sub-valve 5, is embodied of one piece with or is rigidly embodied together with the armature rod 60, for example in a single manufacturing step. As a result, the slider 63 extends through the control chamber 10 from the orifice 4 of the control valve 3 into the sub-valve orifice 50 of the sub-valve 5. To support the slider 63 in the control chamber 10, a bearing element 13 is therefore provided, which in the exemplary embodiment shown here, is connected to the orifice 4; it can, however, also be supported in the wall surrounding the control chamber 10.

(23) As has already been explained, the control pressure p2 is controlled by setting the pressure drop via the control valve 3 and/or the orifice 4.

(24) In this case, the control valve 3 and the orifice 4 disconnect the control chamber 10 from a return chamber 11; preferably, the return chamber 11 is simultaneously connected to a collecting receptacle or reservoir for the medium, in particular the hydraulic fluid; the return pressure p3 prevails in the return chamber 11.

(25) The movement of the control element 2 now occurs parallel to the movement direction of the armature rod 60, which in turn is moved parallel to its longitudinal axis 64 by the drive component II/electromagnet 6.

(26) In the exemplary embodiment shown here, the longitudinal axis 64 is at least parallel, if not in fact identical, to the longitudinal axis 40 of the orifice.

(27) FIGS. 1b and 2b show the design of the control valve 3 in detail, in particular the cooperation of the control element 2 with the orifice 4 according to the invention.

(28) FIG. 1b shows the orifice 4. It is composed of a through opening 47, which passes through the orifice element 45. The through opening 47 is also described by the longitudinal axis 40 of the orifice, which constitutes its central axis, for example. The flow direction of the medium is labeled with the reference letter S. In the flow direction S, the through opening 47 initially has a first, smaller diameter and/or cross-section; at the upper end, this is then adjoined by an annular shoulder 46, which leads to a corresponding widening to the diameter b. With reference to the flow direction S, the control element 2 cooperates with the orifice 4 from the rear; in this case, the pressurized medium tries to lift the control element 2 away from the orifice 4 (by contrast with the situation in the sub-valve 5); the drive component II is provided for this purpose and exerts the necessary adjusting force.

(29) In the direction opposite from the flow direction S, the control element 2 is adjoined by the slider 63, which extends through the through opening 47 in the direction of the control chamber 10.

(30) This annular shoulder 46 forms two orifice regions 41, 42 that are distanced or spaced apart from each other in relation to the longitudinal axis 40 of the orifice; the first orifice region in the flow direction S is labeled with the reference numeral 41 and the second orifice region is labeled with the reference numeral 42. These orifice regions 41, 42 cooperate with corresponding control element regions 21, 22 of the control element 2; in the example shown here, these orifice regions 41, 42 are embodied in the form of ring-like surfaces oriented at right angles to the orifice axis 40, without restricting the invention to such an embodiment.

(31) The orifice regions 41, 42 are embodied as disk-shaped or flat seats. In this case, the first orifice region 41 is not provided at the edge of the orifice, but inside the orifice, at the annular shoulder 46 and has a smaller diameter or internal width a than the second orifice region 42, which is situated at the terminal edge of the orifice.

(32) Corresponding with the embodiment of the orifice 4 with the first and second orifice region 41, 42, the control element 2 shown in in FIG. 1b also has a first and second control element region 21, 22. In the exemplary embodiment shown in FIG. 1b, both of the control element regions 21, 22 are embodied as valve disks; in other words, the control element regions 21, 22 that cooperate with the first and second orifice regions 41, 42 are likewise embodied as annular surfaces that are oriented essentially at right angles to the longitudinal axis 40 of the orifice and the movement direction B of the control element 2. The first control element region 21 in the flow direction S in this case has a smaller diameter than the second control element region 22 situated downstream of it in the flow direction S; both of them are embodied as disk-shaped or cylindrical and function as valve disks.

(33) Between the two control element regions 21, 22, there is a section or an intermediate control element region 23, which is embodied as cylindrical and, which is determined by means of the thickness of the valve disk, the front end of which (relative to the flow direction S), constitutes the control element region 21. The height or thickness of this intermediate control element region 23 is also described as the control element region spacing f.

(34) The two orifice regions 41, 42 are also spaced apart from each other by an intermediate orifice region or section 43, which is depicted in FIGS. 1b and 2b in the form of cylindrical inner surfaces with constant diameters.

(35) Whenever this application speaks of the cooperation of the control element regions 21, 22 with the associated orifice regions 41, 42, this is understood (in particular, but not exclusively) to mean the following:

(36) Naturally, the cooperation of the control element regions 21, 22 with the orifice regions 41, 42 is first understood to mean a sealing, i.e. a closing, of the control valve 3. The question of which control element region 21, 22 comes into closing contact with the orifice region 41, 42 ultimately depends on the embodiment of the geometry of the control element region spacing f and the orifice region spacing g. The control element region spacing f in this case is defined such that the two control element regions 21, 22 are spaced apart from each other in the direction of the longitudinal axis 40 of the orifice and thus cooperate at different times and in different ways with the associated, cooperating orifice regions 41, 42.

(37) In addition to the closing of the control valve 3 by the cooperation of the corresponding control element regions 21, 22 with the orifice regions 41, 42, however, a cooperation also takes place by means of a throttling action, which occurs when the flow cross-section is narrowed by the cooperation of the first or second control element region 21, 22 with the first or second orifice region 41, 42. The effect of the invention lies in the fact that in the closed position of the control valve 3, the control pressure p2 prevailing in the control chamber (in a first position) acts on a first (small) control surface 20a of the control element 2. The control surface 20a in this case is provided on the first control element region 21; this region protrudes into the orifice 4. In this position, the first control element region 21 cooperates in a sealing fashion with the first orifice region 41.

(38) In a second, controlled position, in which the control element 2 is lifted (upward) away from the orifice 4, i.e. is partially opened, the control chamber 10 and the return chamber 11 are fluidically connected to each other. The control pressure p2 prevailing in the control chamber 10 in the second position in this case acts on a second control surface 20b, which is provided in the second control element region 22. The second control surface 20b is larger than the first control surface 20a.

(39) The proposal according to the invention will be explained in greater detail, particularly with the aid of the model described below.

(40) It should be noted here that the second control element region 22 cooperates with the second orifice region 42.

(41) The embodiment here is selected so that the cooperation of the first and second control element regions 21, 22 with the corresponding first and second orifice regions 41, 42 produces an (additional) throttle region in the orifice 4, in fact particularly in the region of the larger, second control surface 20b. In this case, the larger control surface 20b is situated downstream of the first, smaller control surface 20a in the flow direction S and possibly also downstream of the resulting throttle produced by it, which with a differentiated approach can result in a pressure reduction.

(42) The term “control pressure” that is defined and used in this application takes into account this possible pressure difference that can potentially occur here and includes it complete from a technical standpoint. Ideally in this model, the control pressure prevailing here is (effectively) the same as the pressure that is present against the (small) first control surface 20a.

(43) FIG. 3 shows the progressive curve M of the control pressure p2 over the current I that is used to power the coil of the electromagnet 6. A characteristic for the progressive curve M of the pressure control valve according to the invention 1 here is the fact that the slope of the curve in the graph steadily increases with the increasing current, whereas with proportional magnets, the usual linear curve L has a constant slope and is invariable (=0) in the second derivative.

(44) In this case, through the parameters of the control element region spacing f and the orifice region spacing g, in particular their ratio to each other, as well as through the selection of the ratio of the internal width/diameter b of the second orifice region 42 the internal width/diameter a of the first orifice region 41, the invention provides a plurality of design-related adjusting screws to adjust and optimize the progressiveness of the curve M.

(45) The embodiment according to FIG. 2b differs from the one in FIG. 1b with regard to the special configuration of the first control element region 21 and of the corresponding first orifice region 41.

(46) In the variant according to FIG. 1b, the first orifice region 41 is embodied as a disk-shaped or flat seat; the control element region 21 that cooperates with it is embodied in the form of a valve disk.

(47) In FIG. 2b here, the first control element region 21 is embodied in the form of a truncated valve cone 29, which cooperates with a corresponding conical seat 49, i.e. a first orifice region 41. The truncated valve cone 29, which constitutes the first control element region 21, is in turn adjoined at the downstream end by a cylindrical intermediate control element region 23 that connects the control element region 21 to the second control element region 22, which is embodied in the form of a disk valve.

(48) The orifice 4 in turn contains an annular shoulder 46 between the second orifice region with the larger diameter b and the first orifice region with the smaller diameter a. The arrangement of the conical seat 49 is now selected so that this conical seat does not extend across the entire transition from the small diameter a to the large diameter b, but instead extends across less than half, in particular less than 40 or 30% of this difference.

(49) Otherwise, the intermediate orifice region 43 is composed of a cylindrical opening in this case as well.

(50) The present filing of claims with the patent application and subsequent filing of claims are without prejudice to seeking further protection.

(51) If upon closer examination, in particular also of the relevant prior art, it is shown that one feature or another is advantageous for the objective of the invention but not crucially important, it is understood that a wording is sought which no longer has such a feature, in particular in the main claim. Such a subcombination is also encompassed by the disclosure of the present patent application.

(52) It is further noted that the forms and variants of the invention described in the various embodiments and shown in the figures may be arbitrarily combined with one another. In this regard, individual or multiple features may be arbitrarily replaced with one another. These feature combinations are likewise disclosed herein.

(53) The back-references stated in the dependent claims refer to the further embodiment of the subject matter of the main claim through the features of the respective subclaim. However, this is not to be construed as forgoing the seeking of independent, objective protection for the features of the back-referenced subclaims.

(54) Features which have been disclosed only in the description, or also individual features of claims which include a plurality of features, may be incorporated at any time into the independent claim or claims as having importance essential to the invention for delimitation from the prior art, even if such features have been mentioned in conjunction with other features, or achieve particularly advantageous results in conjunction with other features.