Slide valve

Abstract

The present invention provides a sliding valve capable of smoothly moving a sliding column. The sliding valve (1) comprises: a sliding column (22) having shoulder portions (22b, 22d, 22f); and a sleeve (21), wherein the sliding column (22) is arranged inside the sliding column (22) so as to be movable in the axial direction, and is provided with an input port (11) and an output port (12), and has a small diameter portion (210a to 210e) inside the sliding column (22), and the pressure and flow of the fluid passing between the shoulder portions (22b, 22d, 22f) and the small diameter portion (210a to 210e) are adjusted by the movement of the sliding column (22), wherein , forming an adjustment portion (P1~P5), which is the space between the radially overlapping parts of the small diameter portion (210a~210e) of the sleeve (21) and the shoulder portion (22b, 22d, 22f) of the sliding column (22), and dividing the small diameter portion (210e) and the shoulder portion (22f) of the adjustment portion (P5) having a smaller cross-sectional area than the cross-sectional area of ​​the two adjustment portions (P3, P4) adjacent on both axial sides of the input port (11) to form a guide portion (G).

Description

Technical Field

[0001] The present invention relates to a slide valve used in automobiles and other equipment to control the pressure and flow of a control fluid in a fluid circuit. Background Art

[0002] A spool valve uses a spool that moves axially, driven by a drive unit such as air, hydraulic pressure, a motor, or a solenoid, to control the pressure and flow rate of a control fluid in a fluid circuit. A conventional spool valve is known, comprising a spool housed in a sleeve and a drive unit disposed at one end of the spool that generates an axial driving force via a solenoid. This spool valve is disposed between a pressure source such as a pump or accumulator and a load, supplying the control fluid, whose pressure and flow rate are adjusted by the movement of the spool, to the load (see Patent Document 1).

[0003] Such a sliding valve is configured with a spring that applies force to the slide toward a driving part. The driving part causes the slide to overcome the force of the spring and move axially. The relative position of the slide with respect to the sleeve is used as the target position. Thus, the flow path connecting the input port and the output port can be adjusted to a target flow area.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2001-263529 (page 3, Figure 1 ) Summary of the Invention

[0007] Problems to be solved by the invention

[0008] In a spool valve such as that disclosed in Patent Document 1, the sliding properties of the spool may deteriorate during actuation. This is particularly noticeable when using high-pressure fluid. This is believed to be because the fluid accumulated in the narrow gap between the spool's outer circumference and the sleeve's inner circumference is susceptible to degradation due to prolonged stationary operation and a drop in temperature, or because the high-pressure fluid causes the spool to press circumferentially against the sleeve's inner surface.

[0009] The present invention has been made in view of such a problem, and an object of the present invention is to provide a spool valve capable of smoothly operating a spool.

[0010] Means for solving problems

[0011] In order to solve the above-mentioned problems, the slide valve of the present invention comprises:

[0012] a strut having a plurality of shoulders; and

[0013] The sleeve has a small diameter portion inside, and the slide column is arranged inside the sleeve so as to be movable in the axial direction and has an input port and an output port.

[0014] The pressure and flow rate of the fluid passing between the shoulder portion and the small diameter portion are adjusted by the movement of the slide column.

[0015] Among them, a plurality of adjustment parts are formed, which are the space between the radially overlapping parts of the small diameter part of the sleeve and the shoulder part of the sliding column, and the small diameter part and the shoulder part of the adjustment part whose cross-sectional area is smaller than the cross-sectional area of ​​the two adjustment parts adjacent to each other on the axial sides of the input port constitute a guide part.

[0016] Thus, at the time of starting, the fluid can be released from the adjustment portions adjacent to the input port on both axial sides, and the spool can be guided in the axial direction by the guide portion, so that the spool can be smoothly operated.

[0017] The adjustment portion formed by the guide portion may be provided adjacent to at least one of the adjustment portions on both axial sides of the input port in the axial direction.

[0018] As a result, the axial distance between the input port into which the fluid flows and the guide portion is shortened, and thus the inclination of the spool can be suppressed, allowing the spool to operate smoothly.

[0019] In the adjusting portion, the adjusting portion formed by the guide portion may have the smallest cross-sectional area.

[0020] This can suppress the inclination of the spool and allow the spool to move smoothly.

[0021] The shoulder portion constituting the guide portion may be arranged closest to a spring that urges the spool.

[0022] This further suppresses the inclination of the spool, allowing the spool to operate smoothly.

[0023] The adjustment portion formed by the guide portion may be provided as an adjustment portion on both sides of the input port and the output port in the axial direction.

[0024] Thus, the spool is supported by the guide portion at two locations separated in the axial direction, thereby preventing the spool from tilting and allowing the spool to operate smoothly.

[0025] Among the shoulder portions, the shoulder portion constituting the guide portion may have the longest axial dimension.

[0026] This increases the contact area between the shoulder portion constituting the guide portion and the small-diameter portion, thereby dispersing the pressing force of the shoulder portion on the small-diameter portion and allowing the spool to operate smoothly. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1is a partial cross-sectional view showing a slide valve in embodiment 1 of the present invention;

[0028] Figure 2 This is an enlarged cross-sectional view showing a valve portion of a slide valve in a closed state according to Embodiment 1 of the present invention;

[0029] Figure 3 This is an enlarged cross-sectional view showing a valve portion of the slide valve in an open state according to the first embodiment of the present invention;

[0030] Figure 4 This is an enlarged cross-sectional view showing a valve portion of a slide valve in a closed state according to a second embodiment of the present invention. DETAILED DESCRIPTION

[0031] Hereinafter, modes for implementing the slide valve of the present invention will be described based on embodiments.

[0032] Example 1

[0033] Reference Figures 1 to 3 The slide valve of Example 1 is described below. Figure 1 The left and right sides when viewed from the front side are described as the left and right sides of the slide valve.

[0034] The slide valve 1 is used in hydraulically controlled equipment such as an automatic transmission of a vehicle, and controls the pressure and flow rate of a control fluid such as hydraulic oil in a fluid circuit.

[0035] like Figure 1 As shown, the slide valve 1 is configured such that a valve portion 2 for regulating the flow rate of a fluid is integrally mounted on a solenoid-based drive portion 3. The drive portion 3 of this embodiment is a general solenoid structure, and therefore its detailed description is omitted.

[0036] like Figure 1 and Figure 2 As shown, the spool valve 1 of this embodiment is a normally closed spool valve, and in a closed state where the coil of a solenoid (not shown) is not energized, the flow path between the input port 11 and the output port 12 is blocked.

[0037] like Figure 1 As shown, the valve portion 2 mainly comprises the following components: a cylindrical sleeve 21; a spool 22, which is fluid-tightly housed within the sleeve 21 and is axially movable; a coiled spring 23, which is attached to the axially right end of the spool 22 and urges the spool 22 axially leftward; and a retainer 24, which is riveted to the axially right end of the sleeve 21 and retains the spring 23. The sleeve 21, spool 22, and retainer 24 are formed from materials such as aluminum, iron, stainless steel, and resin.

[0038] like Figures 1 to 3As shown, the sleeve 21 is formed into a cylindrical shape with both ends open in the axial direction, and is respectively provided with an input port 11, an output port 12, a feedback port 13, an exhaust port 14 and a breathing port 15 that pass through in the radial direction.

[0039] like Figure 2 and Figure 3 As shown, the sleeve 21 is provided with a through hole 21a for accommodating the spool 22 so as to be movable in the axial direction. The inner peripheral surface of the sleeve 21, that is, the inner peripheral surface of the through hole 21a is formed in a circular cross section.

[0040] The inner circumferential surface of the through-hole 21a is provided, in order from the axial left side to the axial right side, with a first annular recess 21b opening to the breathing port 15, a second annular recess 21c opening to the discharge port 14, a third annular recess 21d opening to the output port 12, a fourth annular recess 21e opening to the input port 11, and a fifth annular recess 21f opening to the feedback port 13. Furthermore, the feedback port 13 communicates with the output port 12 via a throttle hole (not shown) on the outer circumference of the sleeve 21.

[0041] The inner circumference of the through-hole 21a is provided with the following sections: a first small-diameter portion 210a formed between the first and second annular recesses 21b and 21c; a second small-diameter portion 210b formed between the second and third annular recesses 21c and 21d; a third small-diameter portion 210c formed between the third and fourth annular recesses 21d and 21e; ​​a fourth small-diameter portion 210d formed between the fourth and fifth annular recesses 21e and 21f; and a fifth small-diameter portion 210e formed axially to the right of the fifth annular recess 21f. Each small-diameter portion is arranged to correspond to a shoulder portion of the spool 22, described later.

[0042] In addition, in this embodiment, the adjustment portion P (P1, P2, P3, P4, P5) refers to the space between the portion where the small diameter portion of the sleeve radially overlaps with the shoulder portion of the sliding column (hereinafter, the "shoulder portion radially overlapping with the small diameter portion" will also be referred to as the "shoulder portion corresponding to the small diameter portion"). The inner and outer peripheries of the adjustment portion P are divided by the shoulder portion of the sliding column and the small diameter portion of the sleeve. The area difference ΔS (ΔS1, ΔS2, ΔS3, ΔS4, ΔS5) between the inner diameter cross-sectional area of ​​the small diameter portion of the sleeve that divides the adjustment portion P and the outer diameter cross-sectional area of ​​the shoulder portion at the portion radially overlapping with the small diameter portion, that is, the cross-sectional area of ​​the adjustment portion P, will be mentioned below.

[0043] For example, in this embodiment, the small-diameter portions that define the adjustment portions P3 and P4 on both axial sides of the input port 11 are the third small-diameter portion 210 c and the fourth small-diameter portion 210 d .

[0044] In this embodiment, the small-diameter portion defining the adjustment portion P5 is the fifth small-diameter portion 210e and constitutes the guide portion G. Furthermore, the guide portion G is composed of the small-diameter portion defining the adjustment portion with the smallest area difference ΔS in the adjustment portion P and the shoulder portion. In other words, the guide portion G defines the adjustment portion with the smallest area difference ΔS.

[0045] In addition, in this embodiment, the inner diameters of the first small diameter portion 210a, the second small diameter portion 210b, the third small diameter portion 210c and the fourth small diameter portion 210d are respectively configured to be approximately the same diameter, and the inner diameter of the fifth small diameter portion 210e is configured to be smaller than the inner diameters of the aforementioned small diameter portions.

[0046] like Figure 2 and Figure 3 As shown, the slide column 22 is formed into a cylindrical shape with a circular cross-section, and is mainly composed of the following parts from the axial left side to the axial right side: a first shoulder portion 22b, which has an axial left end face 22a of the slide column 22; a first small diameter portion 22c, which is formed to have a smaller diameter than the first shoulder portion 22b; a second shoulder portion 22d, which is formed to have a larger diameter than the first small diameter portion 22c; and a third shoulder portion 22f, which is formed to have a smaller diameter than the second shoulder portion 22d.

[0047] In addition, in this embodiment, the shoulder portion that defines the adjustment portions P3 and P4 on both axial sides of the input port 11 is the second shoulder portion 22 d .

[0048] In this embodiment, the third shoulder portion 22 f is the shoulder portion that defines the adjustment portion P5 of the guide portion G. That is, the guide portion G is formed by the fifth small diameter portion 210 e of the sleeve 21 and the third shoulder portion 22 f of the spool 22 .

[0049] In Example 1, the outer diameters of the first shoulder portion 22b and the second shoulder portion 22d are substantially the same, and the outer diameter of the third shoulder portion 22f is smaller than the outer diameters of the first shoulder portion 22b and the second shoulder portion 22d.

[0050] The axial right end surface of the rod 5 constituting the driving portion 3 abuts against the axial left end surface 22a of the slide column 22. Figure 3 As shown, in the open state of the slide valve 1 , the slide rod 22 can move axially together with the rod 5 .

[0051] One end of a coil spring 23, which urges the spool 22 axially leftward, abuts against an annular surface 22g formed on the axially right end surface of the third shoulder 22f of the spool 22. The spring 23 is compressed and retained between the annular surface 22g of the third shoulder 22f and a retainer 24 riveted to the axially right end of the sleeve 21.

[0052] Small gaps are provided in the radial direction between the inner circumferential surfaces of the first small diameter portion 210a, the second small diameter portion 210b, the third small diameter portion 210c, the fourth small diameter portion 210d and the fifth small diameter portion 210e of the sleeve 21 and the outer circumferential surfaces of the first shoulder portion 22b, the second shoulder portion 22d and the third shoulder portion 22f of the sliding column 22, so that the sliding column 22 can move smoothly in the axial direction.

[0053] In detail, Figure 2 In the closed state of the sliding valve 1 shown, the area difference ΔS3 (= ID3 - OD2) between the inner diameter cross-sectional area ID3 of the third small diameter portion 210c of the adjustment portion P3 on the axial left side of the input port 11 and the outer diameter cross-sectional area OD2 of the second shoulder portion 22d corresponding to the third small diameter portion 210c and the area difference ΔS4 (= ID4 - OD2) between the inner diameter cross-sectional area ID4 of the fourth small diameter portion 210d of the adjustment portion P4 on the axial right side of the input port 11 and the outer diameter cross-sectional area OD2 of the second shoulder portion 22d corresponding to the fourth small diameter portion 210d are substantially the same (ΔS3 = ΔS4).

[0054] In addition, the area difference ΔS5 (=ID5-OD3) between the inner diameter cross-sectional area ID5 of the fifth small diameter portion 210e that divides the adjustment portion P5 at the guide portion G and the outer diameter cross-sectional area OD3 of the third shoulder portion 22f corresponding to the fifth small diameter portion 210e is smaller than the area differences ΔS3 and ΔS4 of the adjustment portions P3 and P4 on the axial sides of the above-mentioned input port 11 (ΔS3=ΔS4>ΔS5).

[0055] In addition, in the closed state of the sliding valve 1, the area difference ΔS1 (= ID1 - OD1) between the inner diameter cross-sectional area ID1 of the first small diameter portion 210a dividing the adjustment portion P1 and the outer diameter cross-sectional area OD1 of the first shoulder portion 22b corresponding to the first small diameter portion 210a is constituted to be approximately the same as the area differences ΔS3 and ΔS4 of the adjustment portions P3 and P4 on both axial sides of the input port 11 (ΔS1 = ΔS3 = ΔS4).

[0056] That is, in the closed state of the slide valve 1 of the first embodiment, the area difference ΔS5 of the adjustment portion P5 in the guide portion G is minimized.

[0057] In addition, Figure 3 In the open state of the sliding valve 1 shown, the area difference ΔS2 (= ID2 - OD1) between the inner diameter cross-sectional area ID2 of the second small diameter portion 210b dividing the adjustment portion P2 and the outer diameter cross-sectional area OD1 of the first shoulder portion 22b corresponding to the second small diameter portion 210b is constituted to be approximately the same as the area difference ΔS1 of the adjustment portion P1 (ΔS1 = ΔS2).

[0058] That is, among all the adjustment portions P in the slide valve 1 of the first embodiment, the area difference ΔS5 of the adjustment portion P5 at the guide portion G is minimized.

[0059] Thus, the outer peripheral surface of the third shoulder portion 22 f is guided in the axial direction while being supported by the inner peripheral surface of the fifth small diameter portion 210 e of the sleeve 21 , and the spool 22 can move smoothly.

[0060] Furthermore, the area differences ΔS3 and ΔS4 of the adjustment portions P3 and P4 on both axial sides of the input port 11 are configured to be larger than the area difference ΔS5 of the adjustment portion P5 at the guide portion G. Thus, in the closed state of the slide valve 1, even when the flow path between the input port 11 and the output port 12 is blocked by the second land portion 22d, a portion of the fluid in the fourth annular recess 21e of the input port 11 can flow out to the axially adjacent third annular recess 21d and fifth annular recess 21f through the gaps on both axial sides of the input port 11 (see FIG. 2 ). Figure 2 black arrow).

[0061] Furthermore, when the slide valve 1 is closed or in operation, the amount of fluid flowing out from the fourth annular recess 21e to the third and fifth annular recesses 21d, 21f is set to such an extent that it does not affect the control of the pressure and flow rate of the control fluid in the fluid circuit.

[0062] Thus, when the slide valve 1 is started, the fluid in the fourth annular recess 21e can be released from the gap between the adjustment portions P3 and P4 on both axial sides of the input port 11, that is, the inner circumferential surfaces of the third small-diameter portion 210c and the fourth small-diameter portion 210d of the sleeve 21 and the outer circumferential surface of the second shoulder portion 22d of the slide post 22 corresponding to the third small-diameter portion 210c and the fourth small-diameter portion 210d, and the outer circumferential surface of the third shoulder portion 22f of the slide post 22 that divides the adjustment portion P5 at the guide portion G can be supported by the inner circumferential surface of the fifth small-diameter portion 210e of the sleeve 21 and guided in the axial direction, so that the slide post 22 can move smoothly.

[0063] Furthermore, the spool valve 1 is a normally closed type and is susceptible to the influence of the fluid accumulated in the gaps on both axial sides of the input port 11 during startup. However, as described above, during startup, the fluid can be released from the fourth annular recess 21e into the third annular recess 21d and the fifth annular recess 21f, thereby effectively improving the responsiveness of the spool valve 1.

[0064] Furthermore, when the slide valve 1 is started, even if high-pressure fluid flows from the input port 11 into the fourth annular recess 21e in the sleeve 21, a portion of the high-pressure fluid can be released from the fourth annular recess 21e into the third annular recess 21d and the fifth annular recess 21f through the gaps between the adjustment portions P3 and P4 on both axial sides of the input port 11, thereby suppressing an excessive increase in pressure in the fourth small-diameter portion 210d and reducing the pressing force of the inner circumference of the fifth small-diameter portion 210e of the adjustment portion P5 dividing the guide portion G on the outer circumference of the supported third shoulder portion 22f, thereby facilitating smooth movement of the slide column 22.

[0065] Furthermore, the outer circumferential surface of the spool 22 and the inner circumferential surface of the sleeve 21 both have circular cross-sections. Consequently, the gap between the outer circumferential surface of the spool 22 and the inner circumferential surface of the sleeve 21 is uniformly formed in the circumferential direction, making the spool 22 less susceptible to the influence of the fluid within the sleeve 21 and enabling stable operation of the spool 22.

[0066] Furthermore, the adjustment portion P5 at the guide portion G is axially adjacent to the adjustment portion P4 on the axially right side of the input port 11. This shortens the axial distance between the fourth annular recess 21e, which opens the input port 11 and into which the high-pressure fluid flows, and the fifth small-diameter portion 210e, which defines the adjustment portion P5 at the guide portion G. This prevents tilting of the spool 22 and allows smooth operation of the spool 22.

[0067] Furthermore, in the spool valve 1, the area difference ΔS5 of the adjustment portion P5 at the guide portion G is minimized. Consequently, the clearance of the adjustment portion P5 at the guide portion G is minimized, and the outer circumferential surface of the third shoulder portion 22f immediately contacts the inner circumferential surface of the fifth small-diameter portion 210e due to the inclination of the spool 22. This suppresses the inclination of the spool 22, allowing smooth operation of the spool 22.

[0068] Furthermore, the third shoulder portion 22f, which defines the adjustment portion P5 in the guide portion G, abuts one end of the spring 23, which urges the spool 22, on its annular surface portion 22g formed on its axially right end surface. Specifically, the third shoulder portion 22f is positioned closest to the spring 23 among the shoulder portions formed on the spool 22. Thus, in the adjustment portion P5 in the guide portion G, the outer circumference of the third shoulder portion 22f, which has high alignment performance due to the spring 23, is guided by the inner circumference of the fifth small-diameter portion 210e. This further suppresses tilting of the spool 22 and ensures smooth operation of the spool 22.

[0069] Furthermore, among the land portions formed on the spool 22, the third land portion 22f, which defines the adjustment portion P5 at the guide portion G, is configured to have the longest axial dimension. This increases the contact area between the outer circumferential surface of the third land portion 22f, which defines the adjustment portion P5 at the guide portion G, and the inner circumferential surface of the fifth small-diameter portion 210e. This disperses the pressing force of the third land portion 22f on the fifth small-diameter portion 210e caused by the high-pressure fluid flowing from the input port 11, thereby ensuring smooth operation of the spool 22.

[0070] Furthermore, when the slide valve 1 is mounted on a device, a groove 30 for inserting a retaining pin (not shown) is provided on the outer peripheral portion of the sleeve 21. This outer peripheral portion of the sleeve 21 corresponds to a portion of the fifth small-diameter portion 210e, which is the longest in the axial direction and defines the adjustment portion P5 at the guide portion G. This allows the valve portion 2 to be compact in its axial dimension.

[0071] In addition, the inner diameters of the first small diameter portion 210a, the second small diameter portion 210b, the third small diameter portion 210c and the fourth small diameter portion 210d of the inner circumferential surface of the sleeve 21 are respectively configured to be approximately the same diameter, and the outer diameters of the first shoulder portion 22b, the second shoulder portion 22d and the third shoulder portion 22f of the sliding column 22 are changed, thereby facilitating the processing of the sleeve 21 and the sliding column 22 during the manufacture of the sliding valve 1.

[0072] Example 2

[0073] Next, refer to Figure 4 The slide valve of Example 2 will be described. Regarding the same configuration as that of Example 1, redundant description will be omitted.

[0074] like Figure 4 As shown, in the slide valve 101 of the second embodiment, the outer diameters of the first shoulder portion 122b and the second shoulder portion 122d of the spool 122 are configured to be substantially the same, and the outer diameter of the third shoulder portion 122f is configured to be smaller than the outer diameters of the first shoulder portion 122b and the second shoulder portion 122d.

[0075] The inner diameter of the first small diameter portion 210a' is smaller than the inner diameters of the second small diameter portion 210b, the third small diameter portion 210c, and the fourth small diameter portion 210d, and is larger than the inner diameter of the fifth small diameter portion 210e.

[0076] In detail, Figure 4 In the closed state of the slide valve 101 shown in FIG, the inner diameter cross-sectional area ID of the first small diameter portion 210a' of the adjustment portion P1 is divided 101 The area difference ΔS101 (= ID 101-OD1) and the inner diameter cross-sectional area ID5 of the fifth small diameter portion 210e that divides the adjustment portion P5 at the guide portion G and the outer diameter cross-sectional area OD3 of the third shoulder portion 122f corresponding to the fifth small diameter portion 210e are made substantially the same (ΔS101=ΔS5).

[0077] That is, in the slide valve 101 of the second embodiment, the adjustment portions P1 and P5 where the area difference ΔS is smallest are provided as adjustment portions on both sides of the input port 11 and the output port 12 in the axial direction.

[0078] Thus, the spool 122 is supported by the guide portions G at two locations separated in the axial direction via the adjustment portions P1 and P5 , thereby preventing the spool 122 from tilting and allowing the spool 122 to operate smoothly.

[0079] In addition, the area difference ΔS101 of the adjustment portion P1 is not limited to being approximately the same as the area difference ΔS5 of the adjustment portion P5 at the guide portion G on the axial right side. As long as it is smaller than the area differences ΔS3 and ΔS4 of the adjustment portions P3 and P4 on both axial sides of the input port 11, it can also be constructed to be slightly larger than the area difference ΔS5 of the adjustment portion P5 at the guide portion G.

[0080] While the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and any changes or additions that do not depart from the gist of the present invention are also encompassed by the present invention.

[0081] For example, in the above embodiment, a case where a solenoid is used as the driving portion of the slide valve has been described. However, the present invention is not limited thereto, and the driving portion of the slide valve may be air, hydraulic pressure, a motor, or the like.

[0082] Furthermore, in the above-described embodiment, the inner circumferential surface of the sleeve through-hole is described as being provided with, in order from the axial left side toward the axial right side, a first annular recessed portion for opening the breathing port, a second annular recessed portion for opening the discharge port, a third annular recessed portion for opening the output port, a fourth annular recessed portion for opening the input port, and a fifth annular recessed portion for opening the feedback port. However, this is not limiting, and the correspondence between the ports and the annular recesses may be appropriately modified depending on the configuration of the fluid circuit of the device, etc. For example, if the spool valve is a normally closed type as in the above-described embodiment, the breathing port, feedback port, input port, output port, and discharge port may be formed in the order of the annular recesses from the axial left side toward the axial right side, corresponding to the respective annular recesses.

[0083] In addition, when the slide valve is a normally open type, it can also be formed in the order of breathing port, feedback port, exhaust port, output port, input port, or breathing port, input port, output port, exhaust port, feedback port corresponding to each annular recess from the axial left side to the axial right side.

[0084] Furthermore, in the above-described embodiment, a method has been described in which the fluid in the fourth annular recess is released from the gaps between the adjustment portions on both axial sides of the input port to the third and fifth annular recesses when the slide valve is actuated. However, the present invention is not limited thereto. It is sufficient that the fluid in the fourth annular recess can be released from at least one of the gaps between the adjustment portions on both axial sides of the input port.

[0085] Furthermore, in the above embodiment, the difference in area of ​​the adjustment sections on either axial side of the input port is described as being substantially equal, but the difference in area of ​​the adjustment sections on either axial side of the input port may be different, as long as it is greater than the difference in area of ​​the adjustment sections at the guide portion. For example, by making the difference in area of ​​the adjustment section on the axial right side of the input port greater than the difference in area of ​​the adjustment section on the axial left side of the input port, more fluid within the fourth annular recess is released into the fifth annular recess opening at the feedback port. This can suppress leakage of the control fluid into the third annular recess opening at the output port.

[0086] In addition, on the contrary, the area difference of the adjustment portion on the axial left side of the input port is configured to be larger than the area difference of the adjustment portion on the axial right side of the input port, and the fluid in the fourth annular recess is released more toward the third annular recess opening of the output port, thereby making it easy to discharge the fluid deteriorated in the sleeve to the outside through the output port and the exhaust port during startup.

[0087] Furthermore, the outer circumferential surface of the spool and the inner circumferential surface of the sleeve are not limited to being circular in cross section, and may be, for example, elliptical or polygonal in cross section.

[0088] Furthermore, the adjustment portion at the guide portion having the smallest area difference may not be axially adjacent to the adjustment portions at both axial sides of the input port.

[0089] The shoulder portion of the adjustment portion defining the guide portion with the smallest area difference is not limited to being the longest in the axial direction, but may be substantially the same in axial direction as the other shoulder portions, or may be the shortest.

[0090] Furthermore, in the above-described embodiment, a case where three land portions are formed on the sleeve has been described, but the number of land portions may be two or more.

[0091] In addition, the inner diameters of the small-diameter portions may be configured to have different diameters, or a plurality of small-diameter portions may be configured to have the same diameter.

[0092] Explanation of symbols

[0093] 1: Slide valve; 2: Valve unit; 3: Drive unit; 11: Input port; 12: Output port; 13: Feedback port; 14: Exhaust port; 15: Breathing port; 21: Sleeve; 21a: Through hole; 21b: First annular recess; 21c: Second annular recess; 21d: Third annular recess; 21e: Fourth annular recess; 21f: Fifth annular recess; 22: Spool; 22b: First shoulder; 22c: First small-diameter portion; 22d: Second shoulder; 22f: Third shoulder (a shoulder that forms the guide portion) part); 23: spring; 101: sliding valve; 122: sliding column; 122b: first shoulder portion; 122d: second shoulder portion; 122f: third shoulder portion (shoulder portion constituting the guide portion); 210a: first small-diameter portion; 210a': first small-diameter portion (small-diameter portion constituting the guide portion); 210b: second small-diameter portion; 210c: third small-diameter portion; 210d: fourth small-diameter portion; 210e: fifth small-diameter portion (small-diameter portion constituting the guide portion); G: guide portion; P: adjustment portion; ΔS: area difference.

Claims

1. A slide valve comprising: a strut having a plurality of shoulders; and The sleeve has a small diameter portion inside, and the slide column is arranged inside the sleeve so as to be movable in the axial direction and has an input port and an output port. The pressure and flow rate of the fluid passing between the shoulder portion and the small diameter portion are adjusted by the movement of the slide column. in, A plurality of adjustment portions are formed, which are spaces between radially overlapping portions of the small-diameter portion of the sleeve and the shoulder portion of the sliding column, and the small-diameter portion and the shoulder portion of the adjustment portion whose cross-sectional area is smaller than that of the two adjustment portions adjacent on both axial sides of the input port constitute a guide portion, and the shoulder portion formed by the guide portion has a smaller diameter than the other shoulder portions.

2. The slide valve according to claim 1, wherein The adjustment portion formed by the guide portion is provided adjacent to at least one of the adjustment portions on both axial sides of the input port in the axial direction.

3. The slide valve according to claim 1, wherein Among the adjusting portions, the portion formed by the guide portion has the smallest cross-sectional area.

4. The slide valve according to claim 1, wherein The shoulder portion constituting the guide portion of the shoulder portion is arranged closest to the spring side that urges the spool.

5. The slide valve according to claim 1, wherein The adjustment portion formed by the guide portion is provided as an adjustment portion on both sides of the input port and the output port in the axial direction.

6. The slide valve according to any one of claims 1 to 4, wherein: Among the shoulder portions, the shoulder portion constituting the guide portion has the longest axial dimension.

Images