DE102022203579A1 - Pilot-controllable pressure control valve and hydraulic system of an automatic transmission with a pilot-controllable pressure control valve - Google Patents

Abstract

A pressure control valve (2) for setting a working pressure (p_A) is described with a valve slide (3) which is guided in a longitudinally displaceable manner in a bore (5A) of a valve housing (5). Outer diameters (D3A to D3D) of guide sections (3A to 3D) are each larger than outer diameters of guide sections (3E, 3F), which are arranged in the longitudinal direction (x) of the valve slide (3) between the guide sections (3A to 3D). The valve housing (5) is manufactured with at least one high-pressure valve pocket (2B), with at least one working-pressure valve pocket (2C) and with at least one low-pressure valve pocket (2D). The valve pockets (2B to 2D) each open into the bore. Cast bevels of the valve pockets (2B to 2D) form an acute angle with the longitudinal direction (x) of the valve slide (3). The working pressure valve pocket (2C) is arranged in the longitudinal direction (x) of the valve slide 3 between the high-pressure valve pocket (2B) and the low-pressure valve pocket (2D) in the valve housing (5) and is either dependent on a position of the valve slide (3). with the high-pressure valve pocket (2B) or with the low-pressure valve pocket (2D). A first connecting section (3E) of the valve slide (3) overlaps with the high-pressure valve pocket (2B) over the entire travel of the valve slide (3). In addition, a hydraulic system (1) of an automatic transmission with a pilot-controllable pressure control valve (2) is proposed.

Description

The invention relates to a pilot-controllable pressure control valve for setting a working pressure with at least one valve slide according to the type defined in more detail in the preamble of claim 1. The invention further relates to a hydraulic system of an automatic transmission, in particular an automatic vehicle transmission, with such a pilot-controllable pressure control valve.

To control actuators in automatic transmissions with a working pressure, pilot-controllable pressure control valves are usually used, by means of which the working pressure can be adjusted depending on a supply pressure. A pilot control stage is usually assigned to at least one such pilot control pressure control valve for pilot control. Most pressure control valves are assigned to exactly one hydraulic interface in order to supply it with a working pressure or a volume flow. Pilot-controllable pressure control valves are controlled with a pilot pressure that is set in the range of a pilot control stage. Alternatively, pilot-controllable pressure control valves are assigned to pilot control stages that are designed as electromagnetic actuators. The electromagnetic actuator then acts directly on a valve slide of the pilot-controllable pressure control valve in order to vary the working pressure.

A supply pressure is applied to a so-called high-pressure valve pocket of a pilot-controllable pressure control valve. To regulate the working pressure, the high-pressure valve pocket can be connected to or decoupled from a working pressure valve pocket by actuating the valve slide, which is longitudinally displaceable in a bore of a valve housing. The working pressure valve pocket is arranged between the high-pressure valve pocket and a low-pressure valve pocket, which is also referred to as a tank pressure valve pocket and in which the ambient pressure or atmospheric pressure is usually present. If necessary, the working pressure in the working pressure valve pocket is reduced in the direction of the low-pressure valve pocket when the valve slide is actuated accordingly.

The working pressure set in each case is a quasi-stationary multiple of the pilot pressure or the electromagnetic pilot stage. The circuit represents a hydraulic pressure amplifier circuit or a quasi-stationary mapping of the input force of the electromagnetic actuator to the pressure level of the working pressure.

At typical operating points, when a hydraulic capacity connected to the working pressure valve pocket is loaded, the pilot-controllable pressure control valve is in valve overlap and works as a hydraulic half bridge. In the present case, the term valve overlap is understood to mean the different distance between control edges of the low-pressure valve pocket and the high-pressure valve pocket in the valve housing manufactured by casting and between control edges of the valve slide, which each interact with the control edges of the valve housing in the area of the low-pressure valve pocket and the high-pressure valve pocket .

The problem here, however, is that the valve pockets each have to be designed as so-called full pockets. If the valve pockets are designed as full pockets, the valve pockets in the valve housing extend in the circumferential direction of the bore in the valve housing, in which the valve slide of the pilot-controllable pressure control valve is arranged to be longitudinally displaceable, over the entire circumference of the bore and open into the bore. When producing the valve pockets in the valve housing using casting technology, production-related bevels in the area of the lateral boundaries or the flanks of the valve pockets are unavoidable. These casting bevels cause transverse forces to occur especially in the area of the highest pressure level of a pilot-controllable pressure control valve, i.e. particularly in the area of the high-pressure valve pocket. These transverse forces act on the valve slide in the transverse direction and press it, at least in some areas, against the inside of the bore. The transverse forces then influence the friction behavior in the area of the contact surface between the outside of the valve slide and the inside of the bore in the valve housing.

At high pressure levels of the supply pressure, the unfavorable friction behavior results in frictional forces which, under certain circumstances, have such a detrimental effect on the movement behavior of the valve slide in the valve housing that the valve slide becomes jammed and can no longer be moved.

To reduce the pressure-related transverse forces, grooves are made in the outside of the valve slide. The grooves extend in the circumferential direction of the valve slide and enable pressure equalization in the circumferential direction. Due to the pressure equalization, the pressure-related transverse forces applied to the valve slide are reduced. Such a special groove on the valve slide is preferably provided in the area of valve pockets produced by casting technology, the flanks of which have a strong inclination relative to a transverse direction of the pressure control valve.

Grooving a valve slide enables at least partial relief of transverse forces on the valve slide. If this is not sufficient, the sloping edges of valve pockets or their cast bevels are reflected or removed. For this purpose, additional manufacturing steps are required during the production of a pilot-controllable pressure control valve, during which the sloping cast flanks of the valve pockets are machined. The aim of machining the flanks of the valve pockets is that at the end of the manufacturing process they run perpendicular to the longitudinal direction of the valve slide and are therefore 90° to the bore.

Both the grooving of a valve slide and the so-called mirroring of the cast bevels of the valve pockets increase the manufacturing costs of pilot-controlled pressure control valves to an undesirable extent. Furthermore, the above-described pilot-controllable pressure control valves are characterized by an undesirably high space requirement, particularly in the area of the full pockets.

Pressure control valves are, among other things, from the DE 10 2012 202 760 A1 , the DE 10 2014 207 801 A1 , the DE 10 2016 223 178 A1 and the DE 10 2018 208 755 A1 known.

It is a preferred object of the present invention to reduce or eliminate at least one disadvantage of a previously known solution or to propose an alternative solution. It is in particular a preferred object of the invention disclosed here to provide a pilot-controllable pressure control valve, in particular a pilot-controllable pressure control valve of a hydraulic system of an automatic transmission, which is or are improved with regard to at least one of the following factors: manufacturing time, manufacturing costs, complexity of manufacturing, utilization of installation space, operational safety, Sustainability and/or component reliability. Other preferred tasks may arise from the beneficial effects of the technology disclosed herein.

A particularly preferred object of the present invention is to provide a pilot-controllable pressure control valve, in particular a pilot-controllable pressure control valve of a hydraulic system of an automatic transmission, which is space-efficient, has the highest possible robustness with respect to casting tolerances and can be manufactured with the lowest possible processing effort after a valve housing has been manufactured using casting technology .

According to the invention, this task(s) is/are solved based on the preamble of patent claim 1 in conjunction with its characterizing features.

A pilot-controllable pressure control valve for setting a working pressure with at least one valve slide is proposed, which is guided in a longitudinally displaceable manner in a bore of a valve housing in the area of guide sections. The outer diameters of the guide sections are each larger than the outer diameters of guide sections which are arranged in the longitudinal direction of the valve slide between the connecting sections of the valve slide.

The valve housing is manufactured using casting technology with at least one high-pressure valve pocket, with at least one working pressure valve pocket and with at least one low-pressure valve pocket, each of which opens into the bore.

Flanks of the high-pressure valve pocket, the working pressure valve pocket and the low-pressure valve pocket have casting bevels and, after casting the valve housing, form an acute angle with the longitudinal direction of the valve slide. The working pressure valve pocket is arranged in the longitudinal direction of the valve slide between the high-pressure valve pocket and the low-pressure valve pocket in the valve housing. Furthermore, the working pressure valve pocket is connected either to the high-pressure valve pocket or to the low-pressure valve pocket, depending on a position of the valve slide.

According to the invention, a first connecting section of the valve slide is in overlap with the high-pressure valve pocket over the entire travel of the valve slide.

In other words, the mouth area of the high-pressure valve pocket is released into the bore of the valve housing over the entire travel of the valve slide through the first connecting section. For this purpose, the outer diameter of the outside of the valve slide in the area of the first connecting section is smaller than the inner diameter of the bore of the valve housing in the area of the high-pressure valve pocket. This means that the outside of the first connecting section of the valve slide in the area of the high-pressure valve pocket is spaced from the inside of the bore in the radial direction of the valve slide, regardless of the current position of the valve slide in the valve housing. The supply pressure in the high-pressure valve pocket is therefore applied to the valve slide over the entire circumference of the valve slide over the defined axial length of the connecting section.

This ensures in a simple manner that no transverse forces act on the valve slide, which impair the functioning of the pressure control valve and result from the high pressure that is applied to the valve slide of the pressure control valve in the area of the high-pressure valve pocket. Therefore, the flanks of the high-pressure valve pocket of the pressure control valve designed according to the invention are not to be reflected after the valve housing has been manufactured by casting technology, as is the case with known pilot-controllable pressure control valves, in order to avoid undesirable transverse forces that act on the valve slide.

A second connecting section of the valve slide can be in overlap with the low-pressure valve pocket over the entire travel of the valve slide. Then, in the area of the low-pressure valve pocket, transverse forces that act on the valve slide and impair the functioning of the pressure control valve according to the invention are avoided in a structurally simple manner.

The outer diameters of the guide sections, between which the first connecting section is arranged, are the same in an easily operable embodiment of the pilot-controllable pressure control valve according to the invention. This ensures that the valve slide can be actuated with low hysteresis essentially independently of the high pressure applied.

If the outer diameters of the guide sections between which the second connecting section is arranged are the same, the valve slide of the pilot-controllable pressure control valve according to the invention can also be moved or actuated essentially independently of the pressure in the area of the low-pressure valve pocket.

In a further advantageous embodiment of the pilot-controllable pressure control valve according to the invention, it can be provided that a guide section adjacent to the first connecting section and a guide section adjacent to the second connecting section are provided between the first connecting section and the second connecting section. The outer diameter of the guide section that adjoins the first connection section can be larger than the outer diameter of the guide section that adjoins the second connection section. The pressure in the working pressure valve pocket can be applied to the differential surface between the mutually facing control surfaces of the valve slide, which are each limited by the outer diameters of the guide sections and the second connecting section. The working pressure then advantageously acts on the valve slide in an adjusting direction of the valve slide, which causes a reduction in a volume flow starting from the high-pressure valve pocket in the direction of the working pressure valve pocket and an increase in the volume flow starting from the working pressure valve pocket in the direction of the low-pressure valve pocket. The control function of the pressure control valve is then implemented in a structurally simple manner.

Furthermore, it can be provided that the flanks of the working pressure valve pocket of the valve housing are machined after casting the valve housing and, after the machining, form at least approximately a right angle with the longitudinal direction of the valve slide. Then, in the area of the working pressure valve pocket, undesirable transverse forces, which act on the valve slide and impair the functioning of the pilot-controllable pressure control valve, are easily avoided.

If the high-pressure valve pocket extends in the circumferential direction of the bore only over part of the circumference of the bore in the valve housing and opens into the bore, the pilot-controllable pressure control valve according to the present invention is characterized by a small space requirement in the area of the high-pressure valve pocket.

In a further space-saving embodiment of the pilot-controllable pressure control valve according to the invention, the low-pressure valve pocket extends in the circumferential direction of the bore only over part of the circumference of the bore in the valve housing and opens into the bore.

The working pressure valve pocket can extend in the circumferential direction of the bore over the entire circumference of the bore in the valve housing and open into the bore.

Via a pilot pressure valve pocket of the pressure control valve according to the invention, a pilot pressure can be applied in the area of a control surface of the valve slide of the pressure control valve, which acts on the valve slide in an actuating direction of the valve slide. If an adjusting movement of the valve slide in this adjusting direction causes an increase in the volume flow starting from the high-pressure valve pocket in the direction of the working pressure valve pocket and a reduction in the volume flow starting from the working pressure valve pocket in the direction of the low-pressure valve pocket, the pressure control valve requires little effort pre-taxable.

An actuating force from an electromagnetic actuator can be applied to the valve slide. Included The actuating force for pilot control of the pressure control valve according to the invention can act on the valve slide in an adjusting direction of the valve slide, which results in an increase in the volume flow starting from the high-pressure valve pocket in the direction of the working pressure valve pocket and a reduction in the volume flow starting from the working pressure valve pocket in the direction of the low pressure -Valve pocket effects.

The pressure control valve can comprise a spring unit, the spring force of which acts on the valve slide in an adjusting direction of the valve slide, which increases a volume flow starting from the working pressure valve pocket in the direction of the low-pressure valve pocket and a reduction in a volume flow starting from the working pressure valve pocket in the direction of High pressure valve bag causes. This ensures that the pressure control valve according to the invention changes into a predefined position or into a predefined operating state in the unpressurized state or below a defined pressure level of the pressure in the high-pressure valve pocket. The pressure control valve can then be actuated to the desired extent based on a defined operating state.

The working pressure valve pocket of the pressure control valve, which is provided in the valve housing, can each have an inner diameter that is larger than the outer diameter of the valve slide.

In addition, it is possible that the inside diameters of the high-pressure valve pocket and the low-pressure valve pocket of the pressure control valve according to the invention are each larger than the outside diameter of the valve slide.

Furthermore, a hydraulic system of an automatic transmission, in particular an automatic vehicle transmission, with a pilot-controllable pressure control valve described in more detail above is proposed.

The pilot-controllable pressure control valve described here and its valve slide form a mechanical regulator which is connected to a high-pressure line, to a working pressure line, to a low-pressure line or a tank pressure line and preferably to a pilot pressure line of the hydraulic system.

Capacitive hydraulic loads such as clutches or brakes are usually supplied with hydraulic fluid via working pressure lines. The pilot pressure of a pilot stage present at the pilot pressure connection is increased by the balance of forces on the valve slide to a higher pressure level in the working pressure line. The same happens if the valve slide is actuated or pilot-controlled directly by an electromagnetic actuator instead of via a pilot pressure. In the case of a pressure-side pilot control, the gain is predetermined by the valve geometry of the pressure control valve, whereby the gain can be implemented constructively by means of a jump in diameter in the area of the valve slide between the working pressure valve pocket and the high-pressure valve pocket.

The invention is not limited to the specified combination of the features of the independent claim or the claims dependent thereon. There are also possibilities to combine individual features with one another, even if they emerge from the claims, the following description of embodiments or directly from the drawing. The reference of the claims to the drawings using reference numerals is not intended to limit the scope of the claims.

Preferred further developments result from the subclaims and the following description. Exemplary embodiments of the invention are explained in more detail with reference to the drawing, without being limited to this.

The only figure in the drawing shows a partial view of a circuit diagram of a hydraulic system of an automatic transmission with a pilot-controllable pressure control valve for setting a working pressure with at least one valve slide.

The figure shows part of a circuit diagram of a hydraulic system 1, which includes a pilot-controllable pressure control valve 2 with a defined valve overlap Udk. The pressure control valve 2 is provided for setting a working pressure p_A, which is present in a working pressure line 4. The working pressure line 4 branches off from the pressure control valve 2 in the direction of an actuator system of an automatic transmission, not shown. The actuator system can include a clutch, a brake, a parking lock cylinder or the like. The pressure control valve 2 has a valve slide 3, which is guided in a longitudinally movable manner in a bore 5A of a valve housing 5.

The hydraulic system 1 is also designed with a high-pressure line 6, which represents a so-called supply pressure line and in which a so-called system pressure p_sys is present. In addition, the hydraulic system 1 includes a low-pressure line 7, which is also referred to as a tank pressure line and in which essentially the ambient pressure or the atmospheric ambient pressure p_∞ is present.

The high-pressure line 6 is connected to a high-pressure valve pocket 2B, while the working pressure line 4 is coupled to a so-called working pressure valve pocket 2C of the pressure control valve 2. The low-pressure line 7 branches off from a so-called low-pressure valve pocket 2D of the pressure control valve 2 in the direction of a hydraulic fluid reservoir (not shown) or an oil sump of the automatic transmission. The working pressure valve pocket 2C is here arranged in the axial direction x between the high-pressure valve pocket 2B and the low-pressure valve pocket 2C.

For pilot control, the pressure control valve 2 includes a pilot pressure valve pocket 2A, to which a pilot pressure line 8 is applied. Via the pilot pressure line 8, a pilot pressure p_EDS can be applied directly to a control surface 9 of the valve slide 3, which can be adjusted in the area of an electro-hydraulic pressure actuator (not shown).

Alternatively or in addition to this, there is also the possibility that the valve slide 3 in the area of the control surface 9, which is equal to an end face of the valve slide 3, is subjected to a positioning force directly by an electromagnetic actuator and in the valve housing 5 as required to adjust the working pressure p_A in axial direction x is adjusted translationally.

The pilot pressure p_EDS or the actuating force of the electromagnetic actuator is applied to the valve slide 3 in an actuating direction of the valve slide 3, which causes an increase in the volume flow starting from the high-pressure valve pocket 2B in the direction of the working pressure valve pocket 2C and a reduction in the volume flow starting from the working pressure valve pocket 2C towards the low pressure valve pocket 2D.

In addition, the pressure control valve 2 includes a spring unit 10, which applies an actuating force to the valve slide 3. The actuating force of the spring unit 10 actuates the valve slide 3 in an actuating direction which results in an increase in a volume flow starting from the working pressure valve pocket 2C in the direction of the low-pressure valve pocket 2D and a reduction in the volume flow from the high-pressure valve pocket 2B in the direction of the working pressure valve pocket 2C effects.

The valve slide 3 of the pressure control valve 2 is designed with four valve slide sections 3A to 3D, each of which represents guide sections of the valve slide 3. The valve slide 3 is guided in a longitudinally displaceable manner in the bore 5A of the valve housing 5 produced by casting technology via the guide sections 3A to 3D. Between the guide sections 3A and 3B as well as 3C and 3D, further valve slide sections 3E, 3F are provided in the axial direction x of the valve slide 3, which are also referred to below as connecting sections. The outer diameters D3A to D3D of the guide portions 3A to 3D are larger than the outer diameters D3E and D3F of the connecting portions 3E and 3F.

The high-pressure valve pocket 2B and the low-pressure valve pocket 2D extend in the circumferential direction of the bore 5A of the valve housing 5 over only part of the circumference of the bore 5A in the valve housing 5 and each open into the bore 5A. The high-pressure valve pocket 2B and the low-pressure valve pocket 2D thus form so-called partial pockets or so-called one-sided valve pockets, and the pressure control valve 2 is in the peripheral area of the bore 5A, in which the high-pressure valve pocket 2B and the low-pressure valve pocket 2D are provided, with a low space requirements. In contrast to this, the working pressure valve pocket 2C is designed as a so-called full pocket and extends in the circumferential direction of the bore 5A over the entire circumference of the bore 5A in the valve housing 5 and opens into it.

The valve overlap Udk of the pressure control valve 2 corresponds to the difference between an axial distance X3 and an axial distance X5. The axial distance X3 corresponds to a distance between a control edge 3B1 of the guide section 3B, which faces away from the guide section 3C, and a further control edge 3C1 of the guide section 3C, which faces away from the guide section 3B. In addition, the axial distance X5 is equal to the axial width of the working pressure valve pocket 2C, which is limited in the axial direction x by the two control edges 2C1 and 2C2.

The valve housing 5 is manufactured by casting, which is why the pilot pressure valve pocket 2A, the high-pressure valve pocket 2B, the working pressure valve pocket 2C, the low-pressure valve pocket 2D and a vent valve pocket 2E each have so-called casting bevels after the casting manufacturing process. In other words, side flanks 2BF1, 2BF2 of the valve pockets 2A to 2E are each designed to run obliquely due to the casting manufacturing process and each form an acute angle with the longitudinal direction x of the pressure control valve 2 or the valve slide 3.

In the exemplary embodiment of the pressure control valve 2 shown in the figure, the flanks 2CF1, 2CF2 of the working pressure valve pocket 2C are machined after the casting manufacturing process and close with the longitudinal direction x of the valve slide 3 forms a right angle. As a result, in the area of the working pressure valve pocket 2C, undesirable transverse forces, which result from the working pressure p_A applied to the outer circumference of the valve slide 3, are avoided with as little manufacturing effort as possible.

In order to avoid transverse forces acting on the valve slide 3 in the area of the high-pressure valve pocket 2B, which result from the high pressure or system pressure p_sys, which is applied to the valve slide 3 and on the cast bevels of the flanks 2BF1, 2BF2 of the high-pressure valve pocket 2B, the Connecting section 3E of the valve slide 3 in the axial direction x over a defined axial length. The axial length of the connecting section 3E is designed so that the first connecting section 3E of the valve slide 3 is in overlap with the high-pressure valve pocket 2B over the entire travel of the valve slide 3 and its outside is spaced in the radial direction R from the inside of the bore 5A .

This design of the valve slide 3 offers the possibility of not having to rework the high-pressure valve pocket 2B after the casting manufacturing process of the valve housing 5 in order to eliminate the casting bevels of the flanks 2BF1, 2BF2 of the high-pressure valve pocket 2B and transverse forces acting in this area of the valve slide to avoid. The elimination of cast bevels of valve pockets of pressure control valves is generally also referred to as mirroring, during which oblique flanks of valve pockets are preferably reworked using special milling cutters so that they then stand or run at 90 ° to the course of the bore 5A.

In addition, undesirable transverse forces acting on the valve slide 3 in the area of the low-pressure valve pocket 2D are avoided in that the guide section 3F of the valve slide 3 is in overlap with the low-pressure valve pocket 2D over the entire travel of the valve slide 3 and the outside of the second connecting section 3F the inside of the bore 5A is spaced in the radial direction. For this reason, the flanks 2DF1, 2DF2 of the low-pressure valve pocket 2D are still designed to run obliquely relative to the axial direction x of the pressure control valve 2 and each form an acute angle with the longitudinal direction x of the valve slide 3.

The outer diameters D3A and D3B of the guide portions 3A and 3B of the valve spool 3, between which the connecting portion 3E is arranged, are the same. In addition, the diameters D3C and D3D of the guide sections 3C and 3D of the valve slide 3, between which the connecting section 3F is arranged, are also the same size. This ensures that the valve slide 3 can be actuated independently of the prevailing system pressure p_sys and the ambient pressure p_∞.

Furthermore, the outer diameter D3B of the guide section 3B is larger than the outer diameter D3C of the guide section 3C. The valve slide 3 thus has a differential surface or a control surface 11 at the transition between the guide section 3B and the guide section 3C of the valve slide 3, on which the working pressure p_A is applied in the longitudinal direction x and the valve slide 3 is subjected to an actuating force.

The actuating force acts on the control surface 11 in an actuating direction of the valve slide 3, which causes a reduction in a volume flow starting from the high-pressure valve pocket 2B in the direction of the working pressure valve pocket 2C and an increase in a volume flow starting from the working pressure valve pocket 2C in the direction Low pressure valve pocket 2D effects. The spring force of the spring unit 10 thus acts in the same way as the working pressure p_A on the differential surface 11 between the guide sections 3B and 3C on the valve slide 3.

The pressure control valve 2 represents a mechanical regulator which regulates the working pressure p_A depending on the system pressure p_sys, the ambient pressure p_∞ and the pilot pressure p_EDS and/or the respective electromagnetic actuating force of an electromagnetic actuator.

Reference symbols

1

Hydraulic system

2

Pressure control valve

2A

Pilot pressure valve bag

2 B

High pressure valve bag

2BF1, 2BF2

Flank of the high pressure valve pocket

2C

Working pressure valve bag

2C1, 2C2

Control edge of the working pressure valve pocket

2CF1, 2CF2

Flank working pressure valve pocket

2D

Low pressure valve bag

2DF1, 2DF2

Flank of the low pressure valve pocket

2E

Vent valve bag

3

valve slide

3A to 3D

Guide section of the valve slide

3B1

Control edge of the valve slide 3

3C1

Control edge of the valve slide 3

3E, 3F

Connecting section of the valve slide

4

Working pressure line

5

Valve housing

5A

Bore of the valve body

6

High pressure line

7

Tank pressure line

8th

Pilot pressure line

9

Control surface of the valve slide 3

10

Spring unit

11

control surface

D3A

Outer diameter of the guide section 3A

D3B

Outer diameter of the guide section 3B

D3C

Outer diameter of the guide section 3C

D3D

Outer diameter of the guide section 3D

D3E

Outer diameter of the connecting section 3E

D3F

Outer diameter of the connecting section 3F

p_A

Working pressure

p_EDS

Pilot pressure

p_sys

System pressure

p_∞

Ambient pressure

R

radial direction of the pressure control valve

Udk

Valve overlap of the pressure control valve

X3

Axial distance between the control edges 3B1 and 3C1 of the valve slide 3

X5

axial distance between the control edges 2C1 and 2C2 of the valve housing 5

x

axial direction, longitudinal direction of the valve slide 3

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102012202760 A1 [0011]
• DE 102014207801 A1 [0011]
• DE 102016223178 A1 [0011]
• DE 102018208755 A1 [0011]

Claims (13)

Pilot-controllable pressure control valve (2) for setting a working pressure (p_A) with at least one valve slide (3), which is guided in a longitudinally displaceable manner in a bore (5A) of a valve housing (5) in the area of guide sections (3A to 3D), the outer diameter (D3A to D3D) of the guide sections (3A to 3D) are each larger than the outer diameters (D3E, D3F) of connecting sections (3E, 3F) of the valve slide (3) arranged in the longitudinal direction of the valve slide (3) between the guide sections (3A to 3D), wherein the valve housing (5) is manufactured by casting with at least one high-pressure valve pocket (2B), with at least one working pressure valve pocket (2C) and with at least one low-pressure valve pocket (2D), each of which opens into the bore (5A), whereby After casting the valve housing (5), align the flanks (2BF1 to 2DF2) of the high-pressure valve pocket (2C), the working pressure valve pocket (2C) and the low-pressure valve pocket (2D) with the longitudinal direction (x) of the valve slide (3). Include angle, whereby the working pressure valve pocket (2C) is arranged in the longitudinal direction (x) of the valve slide (3) between the high-pressure valve pocket (2B) and the low-pressure valve pocket (2D) in the valve housing (5), and whereby the working pressure Valve pocket (2C) is connected either to the high-pressure valve pocket (2B) or to the low-pressure valve pocket (2D), depending on a position of the valve slide (3), characterized in that a first connecting section (3E) of the valve slide (3) is in overlap with the high-pressure valve pocket (2B) over the entire travel of the valve slide (3). Pilot-controllable pressure control valve Claim 1 , characterized in that a second connecting section (3F) of the valve slide (3) overlaps with the low-pressure valve pocket (2D) over the entire travel of the valve slide (3). Pilot-controllable pressure control valve Claim 1 or 2 , characterized in that the outer diameters (D3A, D3B) of the guide sections (3A, 3B), between which the first connecting section (3E) is arranged, are the same. Pilot-controllable pressure control valve according to at least one of the preceding claims, characterized in that the outer diameters (D3C, D3D) of the guide sections (3C, 3D), between which the second connecting section (3F) is arranged, are the same. Pilot-controllable pressure control valve according to at least one of the preceding claims, characterized in that between the first connecting section (3E) and the second connecting section (3F) there is a guide section (3B) adjacent to the first connecting section (3E) and a guide section (3B) adjacent to the second connecting section (3F). Guide section (3C) are provided, wherein the outer diameter (D3B) of the guide section (3B), which adjoins the first connecting section (3E), is larger than the outer diameter (D3C) of the guide section (3C), which adjoins the second connecting section (3F ), whereby the working pressure is at the differential surface (11) between the mutually facing control surfaces of the valve slide (3), which are each limited by the outer diameters (D3B, D3C) of the guide sections (3B, 3C) and the second connecting section (3F). (p_A) rests in the working pressure valve pocket (2C) and acts on the valve slide (3) in an adjusting direction of the valve slide (3), which reduces a volume flow starting from the high pressure valve pocket (2B) in the direction of the working pressure valve pocket (2C ) and an increase in the volume flow from the working pressure valve pocket (2C) towards the low pressure valve pocket (2D). Pilot-controllable pressure control valve according to at least one of the preceding claims, characterized in that the flanks (2CF1, 2CF2) of the working pressure valve pocket (2C) of the valve housing (5) are machined after casting the valve housing (5) and with the longitudinal direction (x) of the valve slide (3) at least approximately enclose a right angle. Pilot-controllable pressure control valve according to at least one of the preceding claims, characterized in that the high-pressure valve pocket (2B) extends in the circumferential direction of the bore (5A) over only part of the circumference of the bore (5A) in the valve housing (5) and extends into the bore (5A). 5A) opens. Pilot-controllable pressure control valve according to at least one of the preceding claims, characterized in that the low-pressure valve pocket (2D) extends in the circumferential direction of the bore (5A) over only part of the circumference of the bore (5A) in the valve housing (5) and extends into the bore (5A). 5A) opens. Pilot-controllable pressure control valve according to at least one of the preceding claims, characterized in that the working pressure valve cal (2C) extends in the circumferential direction of the bore (5A) over the entire circumference of the bore (5A) in the valve housing (5) and opens into the bore (5A). Pilot-controllable pressure control valve according to at least one of the preceding claims, characterized in that a pilot pressure (p_EDS) can be applied to a control surface (9) of the valve slide (3) on a pilot pressure valve pocket (2A), which is on the valve slide (3) in an adjusting direction of the valve slide (3), which causes an increase in the volume flow starting from the high-pressure valve pocket (2B) towards the working pressure valve pocket (2C) and a reduction in the volume flow starting from the working pressure valve pocket (2C) in the direction of the low-pressure valve pocket (2D) causes. Pilot-controllable pressure control valve according to at least one of the preceding claims, characterized in that an actuating force of an electromagnetic actuator can be applied to the valve slide (3), which acts on the valve slide (3) in an adjusting direction of the valve slide (3), which results in an increase in the volume flow from the high-pressure valve pocket (2B) towards the working pressure valve pocket (2C) and a reduction in the volume flow starting from the working pressure valve pocket (2C) towards the low-pressure valve pocket (2D). Pilot-controllable pressure control valve according to at least one of the preceding claims, characterized in that a spring unit (10) is provided, the spring force of which acts on the valve slide (3) in an adjusting direction of the valve slide (3), which reduces the volume flow starting from the high-pressure valve pocket (2B) in the direction of the working pressure valve pocket (2C) and an increase in a volume flow starting from the working pressure valve pocket (2C) in the direction of the low-pressure valve pocket (2D). Hydraulic system (1) of an automatic transmission, in particular an automatic vehicle transmission, with a pilot-controllable pressure control valve (2) according to one of Claims 1 until 12 .

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