Valve device with a valve housing having several switching tongues

Abstract

Valve device (1) with a valve housing (10) having several switching tongues (2 to 9) and a valve slide (11) arranged longitudinally movable in the valve housing (10) between a first end position and a second end position, which is designed with diameter ranges (12 to 18) that interact with the switching tongues (2 to 9) depending on an axial position, wherein several of the diameter ranges (12, 16, 18; 14, 16) are formed with at least one recess (25, 26, 32) extending in the circumferential direction of the valve slide (11) and at least approximately groove-like, wherein the groove-like recesses (25, 26, 32) each have an operative connection via at least one radial bore (27, 28, 33) extending at least approximately in a radial direction in the valve slide (11) with an axial bore (29) extending in an axial direction in the valve slide (11), wherein a high-pressure switching tongue (6) connectable to a high-pressure area (20) of a pressure system is arranged to represent a pressure between working pressure switching tongues (5, 7) and the high-pressure switching tongue (6) is in contact with a first working pressure switching tongue (5) via a reduced diameter area (15; 15, 17) of the valve slide (11) in a first axial position area of ​​the valve slide (11) and with a second working pressure switching tongue (7) in a second position area of ​​the valve slide (11), wherein the first working pressure switching tongue (5) in the second axial position range of the valve slide (11) is connected via the reduced diameter range (15) to a tank switching tongue (4) which can be coupled to a low pressure range (23) of a pressure system, wherein the second working pressure switching tongue (7) in the first axial position range of the valve slide (11) is connected via a further reduced diameter range (17) to a further tank switching tongue (8) which can be coupled to a low pressure range (23) of a pressure system, wherein the reduced diameter regions (15, 17) are arranged in the axial direction between limiting diameter regions (12, 16, 18) of the valve slide (11) and the limiting diameter regions (12, 16, 18) are each formed with at least one of the recesses (25, 26, 32) which are operatively connected to the axial bore (29) via the at least one radial bore (27, 28, 33) wherein the valve slide (11) is provided in the area of ​​a further diameter range (30) with a further radial bore (31) via which the axial bore (29) is connected to the switching tongues (2 and 3) which in the installed position are directly in operative contact with the low pressure range (23) without throttling, and wherein the recesses (25, 26, 32) are arranged off-center in the area of ​​the limiting diameter ranges (12, 16, 18), where the axial distance between the recesses (25, 26) of the limiting diameter ranges (14, 16) and each of the working pressure switching tongues (5, 7) in defined positions of the valve slide (11) within the first position range and within the second position range of the valve slide (11) is smaller than the distance between the recesses (25, 26) of the limiting diameter ranges (14, 16) and the high-pressure switching tongue (6) and an axial distance between a recess (25, 26) of a limiting diameter range (14, 16) and a working pressure switching tongue (5, 7) in defined positions of the valve slide (11) within the first position range or within the second position range of the valve slide (11) is greater than a distance between the recess (25, 26) of the limiting diameter range (14, 16) and a tank switching tongue (4, 8) associated with the working pressure switching tongue (5, 7).

Description

[0001] The invention relates to a valve device with a valve housing having several switching tongues.

[0002] In valve devices known from practice, which are designed with a valve housing containing multiple switching blades and a valve spool arranged to move longitudinally within the valve housing, a pressure field forms around the valve spool that is not symmetrical, depending on the geometry of the valve housing and the valve spool. The pressure field depends, among other things, on the geometric shape of the valve spool, for example, whether it is conical, straight, or cylindrical. Furthermore, the pressure field is also influenced by any draft angles present in the area of ​​the valve housing bore. An asymmetrical pressure field is particularly likely to occur when the control blades of the valve housing are manufactured using a casting process, as they are then not rotationally symmetrical to the required extent.Asymmetrical pressure fields cause radial and axial forces acting on the valve slide in the area of ​​the valve slide, impairing the functioning of a valve device.

[0003] To homogenize the pressure fields that develop around the circumference of the valve spool, so-called relief grooves are provided in the sealing area between the valve spool and the valve body. These grooves are circumferential recesses that are at least approximately groove-like. While the pressure field remains asymmetrical up to such a relief groove, a constant pressure field exists within the relief groove itself. The pressure field rebuilds outside the relief groove. Therefore, the more relief grooves are provided around the valve spool, the more homogeneous the pressure field becomes in the circumferential direction. A homogeneous pressure field, in turn, results in a rotationally symmetrical force around the spool, corresponding to a central force.The slide valve is then in an almost force-balanced operating state and can be moved to the desired extent with low frictional forces in the valve housing and small actuating forces.

[0004] Typically, hydraulic or pneumatic pressure systems use switching valves to alternately connect a working pressure range to a low-pressure range, a tank, or a high-pressure range carrying system pressure. For example, a working pressure range might be connected to a low-pressure range via a throttling device if the pressure in the working pressure range needs to be vented towards the low-pressure range with defined pressure gradients. In such pressure systems, leakage between the high-pressure range carrying system pressure and the working pressure range is disadvantageous if the working pressure range is connected to the low-pressure range via the valve spool and the pressure in the working pressure range needs to be reduced to the tank pressure level, since the leakage, and therefore the venting time for a volumetric consumption, is highly dependent on temperature and system pressure.

[0005] Generally, leakage occurs in a valve assembly whenever, for example, the gap between the valve body and the valve spool is large or the viscosity of the medium conveyed through the valve assembly is very low. The leakage in the valve assembly is proportional to the pressure difference, the cube of the gap height between the valve body and the valve spool, and the diameter of the valve spool. Furthermore, the leakage is inversely proportional to the viscosity of the medium and the overlap length between the valve spool and the valve body.

[0006] Venting a working pressure range via a throttling device towards a low-pressure range with a defined gradient is necessary, for example, when a hydraulic end-position sensing system for a bidirectionally actuated working piston is arranged upstream of the throttling device, since the quality of the sensor signal is affected by leakage in the area of ​​the valve device. Such an end-position sensing system is known, for example, from DE 10 2010 028 762 A1 of the applicant.

[0007] A changeover valve for reducing compressed air consumption is known from JP S56-113,865 A. US 2,765,808 A discloses a control valve with a valve body having a spool receiving port and an inlet port for receiving liquid under high pressure. A liquid control valve for controlling a liquid system is described in US 2,570,896 A.

[0008] The present invention is based on the objective of providing a structurally simple valve device with a valve housing having several switching tongues and a valve slide arranged longitudinally movable in the valve housing, which can be operated with low actuating forces and in which leakage from a high-pressure area towards a low-pressure area is minimal or completely avoided.

[0009] According to the invention, this problem is solved with a valve device having the features of claim 1 or 2.

[0010] In the valve device according to the invention, comprising a valve housing having several switching tongues and a valve slide arranged longitudinally movable in the valve housing, which is designed with diameter regions that interact with the switching tongues depending on an axial position, several of the diameter regions are formed with at least one recess extending in the circumferential direction of the valve slide and at least approximately groove-like.

[0011] The groove-like recesses are each operatively connected via at least one radial bore extending at least approximately in the radial direction in the valve slide to an axial bore extending in the axial direction in the valve slide, through which leakage originating from a high-pressure area towards the working pressure area and thus also towards the low-pressure area can be avoided in a structurally simple manner if the groove-like recesses are arranged in a diameter range of the valve slide, where the working pressure area is connected to the low-pressure area, and the high-pressure area is separated from the working pressure area.

[0012] A high-pressure switching tongue, connectable to a high-pressure section of a pressure system, of the inventive valve device, which is particularly space-saving in the axial direction, is arranged to represent a pressure between working pressure switching tongues. Within a first axial position range of the valve spool, the high-pressure switching tongue is in contact with a first working pressure switching tongue via a reduced diameter range of the valve spool, and within a second position range of the valve spool, it is in contact with a second working pressure switching tongue.

[0013] In the inventive valve device, which is also space-saving and cost-effective, the first working pressure switching tongue is connected within the second axial positioning range of the valve slide via the reduced diameter range to a tank switching tongue which can be coupled to a low-pressure area of ​​a pressure system.

[0014] In the valve device according to the invention, which can also be operated with minimal control effort, the second working pressure switching tongue within the first axial position range of the valve slide is connected via a further reduced diameter range to a further tank switching tongue, which can be coupled to a low-pressure range of a pressure system.

[0015] Furthermore, leakage between a high-pressure area and at least one working pressure area, as well as between the working pressure area and a low-pressure area, is minimal in the valve device according to the invention, which can be operated with low actuating forces, since the reduced diameter areas limiting the axial diameter areas of the valve slide are each formed with at least one recess extending in the circumferential direction of the valve slide, which is operatively connected to the axial bore via at least one radial bore.

[0016] In other words, this minimizes leakage from a high-pressure area towards a working pressure area and from a working pressure area towards a tank pressure area with minimal design effort, and additionally creates a homogeneous pressure field in the circumferential direction around the valve spool, which enables operation of the valve device with low actuating forces.

[0017] Additionally, the valve spool features a further radial bore in the wider diameter range, through which the axial bore is connected to the switching blades, which are directly and unrestrictedly operatively connected to the low-pressure range. Furthermore, the recesses in the area of ​​the limiting diameter ranges are arranged off-center.

[0018] The axial distance between the recesses of the limiting diameter sections and each of the working pressure switching tongues is, in defined positions of the valve spool within the first position range and within the second position range of the valve spool, smaller than the distance between the recesses of the limiting diameter sections and the high-pressure switching tongue. This allows the valve device according to the invention to be implemented with a small axial installation space requirement while simultaneously providing a high sealing effect.

[0019] Furthermore, an axial distance between a recess of a limiting diameter range and a working pressure switching tongue in defined positions of the valve slide within the first position range or within the second position range of the valve slide is greater than a distance between the recess of the limiting diameter range and a tank switching tongue associated with the working pressure switching tongue.

[0020] In an alternative embodiment of the valve device according to the invention, the axial distance between a recess of a limiting diameter region and one of the working pressure switching tongues, and between the recess of the limiting diameter region and the high-pressure switching tongue in defined positions of the valve spool within the first position range and within the second position range of the valve spool, is essentially the same. This prevents or at least reduces leakage from the high-pressure region towards a working pressure region over the entire operating range of the valve device according to the invention to the desired extent.

[0021] Furthermore, in the alternative embodiment of the valve device according to the invention, the axial distance between a recess of a limiting diameter area and one of the working pressure switching tongues, and between the recess of the limiting diameter area and a tank switching tongue associated with the working pressure switching tongue, is essentially the same in defined positions of the valve slide within the first position area or within the second position area of ​​the valve slide, in order to minimize leakage from the working pressure area towards a low-pressure area. In a further advantageous embodiment of the valve device according to the invention, this is achieved over the entire operating range of the valve device.

[0022] In a further embodiment of the valve device according to the invention, an undesirable pressure build-up in areas of the valve device in which the valve slide can be subjected to a pressure in the area of ​​an effective surface that influences the functioning of the valve device is avoided by providing the recess arranged within the first position range of the valve slide between the first working pressure switching tongue and the tank switching tongue separated from it by the valve slide within the second position range of the valve slide, in which the tank switching tongue is connected to the first working pressure switching tongue, between the tank switching tongue and a further tank switching tongue.

[0023] In a further space-saving embodiment of the valve device according to the invention, the recess arranged within the first position range of the valve slide between the second working pressure switching tongue and the high pressure switching tongue separated from it by the valve slide is provided within the second position range of the valve slide, in which the high pressure switching tongue is connected to the second working pressure switching tongue, between the high pressure switching tongue and the first working pressure switching tongue.

[0024] If a recess of the valve slide is provided within the first position range of the valve slide between the second working pressure switching tongue and the associated tank switching tongue, and within the second position range of the valve slide between the tank switching tongue associated with the second working pressure switching tongue and a further switching tongue, in the area of ​​which the valve slide can be subjected to pressure in the area of ​​an effective surface, a pressure build-up in the area of ​​the further switching tongue that impairs the functioning of the valve device according to the invention is reliably avoided.

[0025] Both the features specified in the claims and the features specified in the following embodiments of the valve device according to the invention are each suitable, individually or in any combination, for further developing the subject matter of the invention. The respective combinations of features do not represent any limitations with regard to the further development of the subject matter according to the invention, but are essentially merely exemplary.

[0026] Further advantages and advantageous embodiments of the valve device according to the invention will become apparent from the claims and the exemplary embodiments described below with reference to the drawing, wherein, for the sake of clarity, the same reference numerals are used in the description of the various exemplary embodiments for components that are identical in construction and function.

[0027] It shows: Fig. 1 a schematic longitudinal sectional view of a first embodiment of the valve device according to the invention in a first switching position; Fig. 2 the valve device according to Fig. 1 in a second switching position; Fig. 3 a single longitudinal section view of a valve slide of the valve device according to Fig. 1; Fig. 4 one Fig. 1. Corresponding illustration of a second embodiment of the valve device according to the invention in a first switching position; and Fig. 5 the valve device according to Fig. 4 in a second switching position.

[0028] Fig. Figure 1 shows a longitudinal sectional view of a first embodiment of a valve device 1 with a valve housing 10 having several switching tongues 2 to 9 and a valve spool 11 arranged to be longitudinally movable in the valve housing 10. The valve spool 11 is designed with diameter ranges 12 to 18 and a further diameter range 30, which interact with the switching tongues 2 to 9 depending on an axial position within the valve housing 10, wherein the diameter ranges 12 and 14 limit a reduced diameter range 13, the diameter ranges 14 and 16 a reduced diameter range 15 and the diameter ranges 16 and 18 a reduced diameter range 17 in the axial direction.

[0029] The valve spool 11 is subjected in its end region associated with the switching tongue 2 to a spring force of a spring device 19, which counteracts a pressure force component resulting from a control pressure p_VS that can be applied in the region of the switching tongue 9 and is shouldered on the valve spool 11 in the transition region between the diameter region 30 and the limiting diameter region 12. The valve spool 1 is in Fig. 1 is shown above the applied control pressure p_VS in its second end position, which is moved against the spring force of the spring device 19. Fig. Figure 2 shows the valve slide 11 in its first end position, which the valve slide 11 assumes below a defined pressure level of the control pressure p_VS due to the applied spring force of the spring device 19.

[0030] The switching tongue 6 of the valve device 1 is connected to a high-pressure area 20 carrying a system pressure p_sys and is hereinafter referred to as the high-pressure switching tongue. The two switching tongues 5 and 7, each adjacent to the high-pressure switching tongue 6, are each connected to a working pressure area 21 and 22, respectively, and are referred to in the following description as the working pressure switching tongues. On the side of the working pressure switching tongues 5 and 7 facing away from the high-pressure switching tongue 6, switching tongues 4 and 8, respectively, are provided. These are each operatively connected to a low-pressure area 23 via a throttling device 24 and are referred to below as the tank switching tongues for clarity. The low-pressure area 23 represents an oil sump of a vehicle's transmission system, the pressure level of which essentially corresponds to ambient pressure.

[0031] In the valve assembly 1, a working pressure tongue 5 or 7 is located between the pressure supply pocket or the high-pressure switching tongue 6 and a tank pocket or a tank switching tongue 4 or 8, respectively. The working pressure ranges 21 and 22 can be supplied with either the system pressure p_sys or the tank pressure of the low-pressure range 23 via the valve assembly 1, which is designed as a 4 / 2-way valve. The valve spool 11 is positioned between the two in this regard. Fig. 1 and Fig. to adjust the 2 shown switching positions, wherein the reduced diameter area 15 of the valve slide 11 connects the high pressure switching tongue 6 either to the working pressure area 21 or to the working pressure area 22.

[0032] In the Fig. In the switching position of the valve spool 11 shown in Figure 1, the high-pressure switching tongue 6 is connected to the working pressure switching tongue 5 via the reduced diameter section 15, while the working pressure switching tongue 7 is separated from the high-pressure switching tongue 6 by the limiting diameter section 16 of the valve spool 11. Simultaneously, the working pressure switching tongue 5 is separated from the tank switching tongue 4 via the limiting diameter section 14 of the valve spool 11, while the working pressure switching tongue 7 is operatively connected to the tank switching tongue 8 via the reduced diameter section 17.This means that the pressure of the working pressure range 21, due to the control pressure p_VS applied to the valve spool 11, essentially corresponds to the pressure level of the system pressure p_sys, while the pressure in the working pressure range 22 decreases with increasing operating time via the throttling device 24 towards the low pressure range 23 with a defined pressure gradient towards the pressure level of the low pressure range 23.

[0033] To prevent leakage from the high-pressure area 20 towards the low-pressure area 23, the limiting diameter areas 14 and 16 of the valve slide 11 are each provided with a circumferentially extending and at least approximately groove-like recess 25, 26, which connects via a radially extending bore 27, 28 in the valve slide 11 to an axially extending bore 27, 28 in the valve slide 11. Fig. The axial bore 29, shown in more detail below, is in operative connection with the valve slide 11. Additionally, the valve slide 11, in the area of ​​the further diameter section 30, in which the spring assembly 19 is provided, is designed with a further radial bore 31, via which the axial bore 29 is connected to the switching tongues 2 and 3, which are directly in operative connection with the low-pressure section 23, so that the axial bore 29 is vented without restriction towards the low-pressure section 23.

[0034] The axial distance between the recesses 25 and 26 of the diameter ranges 14 and 16, which limit the reduced diameter range 15 in the axial direction, and between each of the working pressure switching tongues 5 and 7 in the first or second switching position of the valve spool 11, is smaller than the distance between the recesses 25 and 26 of the limiting diameter ranges 14 and 16 and the high-pressure switching tongue 6. Furthermore, the axial distance between the recesses 25 and 26 of the limiting diameter ranges 14 and 16 and the working pressure switching tongues 5 and 7 in the first or second switching position of the valve spool 11 is greater than the axial distance between the recesses 25 and 26 of the limiting diameter ranges 14 and 16 and the tank switching tongues 4 and 8, respectively, assigned to the working pressure switching tongues 5 and 7.

[0035] The recesses or relief grooves 25 and 26, arranged off-center in the area of ​​the limiting diameter ranges 14 and 16, offer the possibility, in a structurally simple and axially space-saving manner, of ensuring a high degree of overlap and thus a greater sealing effect between the valve spool 11 and the valve housing 10 with respect to the applied system pressure p_sys over the entire operating range of the valve device 1 than with respect to the pressure level that occurs during venting of the working pressure range 21 or the working pressure range 22.

[0036] At the in Fig. 1 and Fig. In the valve device 1 shown in Figure 2, the same pressure differential always acts between the recesses 25 and 26. The leakage originating from the high-pressure area 20 towards the low-pressure area 23 is kept as low as possible by the large overlap length created by the asymmetrical arrangement of the recesses 25 and 26 in the diameter areas 14 and 16 between the high pressure, i.e., the system pressure p_sys or the working pressure of the working pressure area 21 or the working pressure area 22, and the respective low pressure in the area of ​​the tank switching tongues 4 and 8.

[0037] Because of the pressure differences present to a lesser extent in these areas of the valve device 1, a small overlap length is necessary and must be provided between the area of ​​the tank switching tongue 4 or the tank switching tongue 8 and the recesses 25 and 26 to achieve the desired sealing effect in the area between the valve slide 11 and the valve housing 10, the axial installation space requirement of the valve device 1 is minimized in a structurally simple manner due to the asymmetric arrangement of the recesses 25 and 26, and direct leakage from the high pressure p_sys of the high-pressure area 20 towards the throttling device 24 is avoided or reduced to the desired extent.

[0038] Fig. 4 and Fig. Figure 5 shows a second embodiment of the valve device 1, which differs from the embodiment according to Fig. 1 to Fig. 3 differs essentially only by a partially differing design of the valve slide 11, which is why the following description will address the differences between the two embodiments of the valve device 1 and the further functioning of the valve device 1 according to Fig. 4 and Fig. 5 to the description Fig. 1 to Fig. 3 is referred to.

[0039] The valve slide 11 of the valve device 1 according to Fig. 4 and Fig. 5 is designed without the two diameter ranges 13 and 14, which are specified for the valve device 1 according to Fig. 1 to Fig. 3. The tank switching tongue 4 and the working pressure switching tongue 5 can be connected or disconnected from each other. In the design of the valve device 1 according to... Fig. 4 and Fig. 5 will be the tank switching tongue 4 in the in Fig. In the switching position 4 shown, the valve slide 11 is separated from the working pressure switching tongue 5 via the limiting diameter range 12, while the working pressure switching tongue 5 is in the Fig. In the switching position shown in Figure 5, the valve slide 11 is operatively connected to the tank switching tongue 4 via the reduced diameter range 15. The working pressure range 21 is connected to the working pressure switching tongue 7, while the working pressure range 22 is coupled to the working pressure switching tongue 4.

[0040] Since the recess 26 of the diameter range 16 is located between the high-pressure switching tongue 6 and the working pressure switching tongue 7 in the first switching position of the valve spool 11, and between the high-pressure switching tongue 6 and the working pressure switching tongue 5 in the second switching position of the valve spool 11, the recess 26 is arranged centrally within the limiting diameter range 16. This ensures that the axial distance between the recess 26 and the high-pressure switching tongue 6, as well as the distance between the recess 26 and the working pressure switching tongue 5 or 7, is always equal. This is necessary because the high pressure differential between the high system pressure and the low pressure range of the recess 26 changes direction depending on the switching position.

[0041] Additionally, the diameter range 18 of the valve slide 11 of the valve device 1 is according to Fig. 4 and Fig. 5 To prevent direct leakage from the working pressure pocket 7 towards the tank pressure pocket 8, a recess 32 corresponding to the recesses 25, 26 is formed, which is also connected to the axial bore 29 via a radial bore 33. The recess 32 is positioned axially in the diameter range 18 such that a distance between the recess 32 and the working pressure switching tongue 7 as well as a distance between the recess 32 and the tank switching tongue 8 is maintained in the Fig. The 5 shown ways are the same size.

[0042] The design of the valve device 1 according to Fig. 4 and Fig. 5 has the same axial length as the valve device 1 according to Fig. 1 to 3 have a reduced overlap length and thus a lower sealing effect between the valve spool 11 and the valve housing 10 in the area of ​​the limiting diameter range 16. In order not to reduce the sealing effect compared to the valve device 1 between the high-pressure switching tongue 6 and the two working-pressure switching tongues 4 and 6, the overlap length between the valve spool 11 and the valve housing 10 in this area is increased by a design that differs from that of the valve device 1 according to Fig. 1 to Fig. 3. To increase the axial length of the valve slide 11 and the valve housing 10, which, however, leads to an increased slide travel of the valve slide 11 in the valve housing 10, which, however, adversely affects the reaction time of the valve device 1. Reference sign 1 Valve device 2 to 9 switching tongue 10 Valve housings 11 valve slides 12 to 18 mm diameter range of the valve slide 19 Spring assembly 20 High-pressure area 21, 22 Working pressure range 23 Low-pressure area 24 Throttle device 25, 26 recess 27, 28 radial bore 29 Axial bore 30 diameter range 31 additional radial bores 32 recess 33 radial bore p_sys System pressure p_VS control pressure

Claims

[1] Valve device (1) with a valve housing (10) having a plurality of switching tongues (2 to 9) and a valve slide (11) arranged in the valve housing (10) so as to be longitudinally movable between a first end position and a second end position, which is designed with diameter regions (12 to 18) cooperating with the switching tongues (2 to 9) depending on an axial position, wherein several of the diameter regions (12, 16, 18; 14, 16) are formed with at least one recess (25, 26, 32) extending in the circumferential direction of the valve slide (11) and at least approximately groove-like, wherein the groove-like recesses (25, 26, 32) are each operatively connected via at least one radial bore (27, 28, 33) extending at least approximately in the radial direction in the valve slide (11) with an axial bore (29) extending in the axial direction in the valve slide (11), wherein a high-pressure switching tongue (6) connectable to a high-pressure region (20) of a pressure system is arranged to represent a pressure between working pressure switching tongues (5, 7), and the high-pressure switching tongue (6) is connected to a first working pressure switching tongue (5) in a first axial position range of the valve spool (11) via a reduced diameter range (15; 15, 17) of the valve spool (11) and to a second working pressure switching tongue (7) in a second position range of the valve spool (11), wherein the first working pressure switching tongue (5) is connected in the second axial position range of the valve slide (11) via the reduced diameter range (15) to a tank switching tongue (4) which can be coupled to a low-pressure range (23) of a pressure system, wherein the second working pressure switching tongue (7) is connected in the first axial position range of the valve slide (11) via a further reduced diameter range (17) to a further tank switching tongue (8) which can be coupled to a low-pressure range (23) of a pressure system, wherein the reduced diameter regions (15, 17) are arranged in the axial direction between limiting diameter regions (12, 16, 18) of the valve slide (11), and the limiting diameter regions (12, 16, 18) are each formed with at least one of the recesses (25, 26, 32) which are operatively connected to the axial bore (29) via the at least one radial bore (27, 28, 33), wherein the valve slide (11) is designed in the region of a further diameter range (30) with a further radial bore (31), via which the axial bore (29) is connected to the switching tongues (2 and 3), which in the installed position are directly and unthrottledly connected to the low-pressure area (23), and wherein the recesses (25, 26, 32) are arranged off-center in the region of the limiting diameter regions (12, 16, 18), whereby an axial distance between the recesses (25, 26) of the limiting diameter ranges (14, 16) and one of the working pressure switching tongues (5, 7) in each case in defined positions of the valve spool (11) within the first position range and within the second position range of the valve spool (11) is smaller than a distance between the recesses (25, 26) of the limiting diameter ranges (14, 16) and the high-pressure switching tongue (6) and an axial distance between a recess (25, 26) of a limiting diameter range (14, 16) and a working pressure switching tongue (5, 7) in defined positions of the valve spool (11) within the first position range or within the second position range of the valve spool (11) is greater than a distance between the recess (25, 26) of the limiting diameter range (14, 16) and a tank switching tongue (4, 8) assigned to the working pressure switching tongue (5, 7). [2] Valve device (1) with a valve housing (10) having a plurality of switching tongues (2 to 9) and a valve slide (11) arranged in the valve housing (10) so as to be longitudinally movable between a first end position and a second end position, which is designed with diameter regions (12 to 18) cooperating with the switching tongues (2 to 9) depending on an axial position, wherein several of the diameter regions (12, 16, 18; 14, 16) are formed with at least one recess (25, 26, 32) extending in the circumferential direction of the valve slide (11) and at least approximately groove-like, wherein the groove-like recesses (25, 26, 32) are each operatively connected via at least one radial bore (27, 28, 33) extending at least approximately in the radial direction in the valve slide (11) with an axial bore (29) extending in the axial direction in the valve slide (11), wherein a high-pressure switching tongue (6) connectable to a high-pressure region (20) of a pressure system is arranged to represent a pressure between working pressure switching tongues (5, 7), and the high-pressure switching tongue (6) is connected to a first working pressure switching tongue (5) in a first axial position range of the valve spool (11) via a reduced diameter range (15; 15, 17) of the valve spool (11) and to a second working pressure switching tongue (7) in a second position range of the valve spool (11), wherein the first working pressure switching tongue (5) is connected in the second axial position range of the valve slide (11) via the reduced diameter range (15) to a tank switching tongue (4) which can be coupled to a low-pressure range (23) of a pressure system, wherein the second working pressure switching tongue (7) is connected in the first axial position range of the valve slide (11) via a further reduced diameter range (17) to a further tank switching tongue (8) which can be coupled to a low-pressure range (23) of a pressure system, wherein the reduced diameter regions (15, 17) are arranged in the axial direction between limiting diameter regions (12, 16, 18) of the valve spool (11), and the limiting diameter regions (12, 16, 18) are each formed with at least one of the recesses (25, 26, 32) which are operatively connected to the axial bore (29) via the respective at least one radial bore (27, 28, 33), wherein the valve spool (11) is designed in the region of a further diameter region (30) with a further radial bore (31), via which the axial bore (29) is connected to the switching tongues (2 and 3), which, in the installed position, are operatively connected directly to the low-pressure region (23) without being throttled, wherein an axial distance between a recess (26, 32) of a limiting diameter range (16, 18) and one of the working pressure switching tongues (5, 7) and between the recess (26, 32) of the limiting diameter range (16, 18) and the high-pressure switching tongue (6) in defined positions of the valve spool (11) within the first position range and within the second position range of the valve spool (11) is essentially the same size, and wherein an axial distance between a recess (25, 32) of a limiting diameter range (12, 18) and one of the working pressure switching tongues (5, 7) and between the recess (25; 32) of the limiting diameter range (16, 18) and a tank switching tongue (4, 8) assigned to the working pressure switching tongue (5, 7) is essentially the same in defined positions of the valve spool (11) within the first position range or within the second position range of the valve spool (11). [3] Valve device according to claim 2, characterized bythat the recess (25) arranged within the first position range of the valve spool (11) between the first working pressure switching tongue (5) and the tank switching tongue (4) separated therefrom by the valve spool (11) is provided between the tank switching tongue (4) and a further tank switching tongue (3) within the second position range of the valve spool (11), in which the tank switching tongue (4) is connected to the first working pressure switching tongue (5). [4] Valve device according to one of claims 2 or 3, characterized bythat the recess (26) arranged within the first position range of the valve spool (11) between the second working pressure switching tongue (7) and the high-pressure switching tongue (6) separated therefrom by the valve spool (11) is provided between the high-pressure switching tongue (6) and the first working pressure switching tongue (5) within the second position range of the valve spool (11), in which the high-pressure switching tongue (6) is connected to the second working pressure switching tongue (7). [5] Valve device according to one of claims 2 to 4, characterized bythat a recess (32) of the valve spool (11) arranged within the second position range of the valve spool (11) between the second working pressure switching tongue (7) and the associated tank switching tongue (8) is provided within the first position range of the valve spool (11) between the tank switching tongue (8) associated with the second working pressure switching tongue (7) and a further switching tongue (9), in the area of ​​which the valve spool (11) can be subjected to a pressure (p_VS) in the area of ​​an active surface.

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