Quick-switching 2 / 2-directional cartridge valve

Abstract

A fast-switching 2 / 2-way cartridge valve is disclosed, which can be used as a check valve. The closing movement of its closing body is damped by abutment sections that abut against each other and can move toward each other during the closing movement. The abutment sections are formed on the closing body on the one hand and on the valve opening in which the closing body is guided on the other hand.

Description

Technical Field

[0001] The invention relates to a fast-switching 2 / 2-way cartridge valve according to the preamble of claim 1 . Background Art

[0002] The applicant's publication numbered RD21040, "2-Way Cartridge Valve, Actively Actuated Type LC2A," published in May 2017, discloses a 2 / 2-way cartridge valve. This 2 / 2-way cartridge valve has a high-pressure port and a low-pressure port that can be separated or connected to one another.

[0003] Pressure fluctuations caused by rapid closing can lift the control slide off the seat ring for several short periods of time. Due to leakage through the seat area, high pressure can only be built up with a delay. The impact of the control slide on the seat ring caused by rapid closing must be damped. A standard damping section in the seat area is not feasible because, when the control slide moves into the damping section, an active surface pointing in the opening direction of the control slide is formed there, which could reopen the control slide and must therefore be avoided. Summary of the Invention

[0004] In contrast, the object of the present invention is to provide a fast-switching 2 / 2-way cartridge valve which reduces or avoids the aforementioned disadvantages.

[0005] This object is achieved by a fast-switching 2 / 2-way cartridge valve having the features of claim 1 .

[0006] Further advantageous embodiments of the invention are described in the dependent claims.

[0007] The claimed fast-switching 2 / 2-way cartridge valve is designed as a seat valve and comprises a valve housing in which a control slide is guided and on which a seat ring for the control slide is formed. According to the present invention, an end-position damping for the closing movement of the control slide is formed by an outer housing section of the control slide—preferably in the region of its shoulder—and an inner housing section of the valve housing. The high impact energy generated by rapid closing is dissipated by the damping according to the present invention. Consequently, closing times of <10 ms for the cartridge valve can be achieved.

[0008] This damping element has the advantage over conventional damping pins in the seat region that no active surface is formed in the high-pressure region of the cartridge valve in the opening direction. At the same time, any closing of the cartridge valve during flow from the high-pressure port to the low-pressure port can be prevented.

[0009] According to two different embodiments, the two housing sections (of the damping element) are conical or cylindrical. In the first embodiment, the conically shaped region of the control slide is moved into a similarly conically shaped receptacle of the valve housing, which can be a bushing. The damping length, damping angle, and damping gap can be configured differently depending on the desired damping effect. According to the second embodiment, the damping element can be cylindrical. The damping length and damping gap can be configured differently depending on the desired damping effect.

[0010] If the cartridge valve is designed as a non-return valve, it can disconnect the high-pressure connection from the low-pressure connection very quickly (e.g., in less than 10 ms). Non-return valves according to the prior art have a very long closing time (approximately 20 ms). This short closing time is particularly advantageous in die-casting machines, so the non-return valve is preferably designed for die-casting machines.

[0011] The valve housing can be at least partially a sleeve or a tube or sleeve-like or tubular. The inner housing section is then formed on the end section of the valve housing that is arranged opposite the seat area. This end section is preferably installed in the valve block of the cartridge valve.

[0012] In a particularly preferred embodiment, an overlap is provided in the seat region between the valve housing and the control slide, which overlap acts as a closing or blocking element between the high-pressure port and the low-pressure port. This overlap minimizes leakage from the high-pressure port to the low-pressure port when the control slide is briefly lifted.

[0013] If the seat ring of the valve housing and / or the seat ring of the control valve slide is conical, the overlap is preferably formed by an overlap section on the control slide side adjacent to the seat ring of the control slide and an overlap section on the valve housing side adjacent to the seat ring of the valve housing.

[0014] The two overlapping sections are particularly preferably cylindrical. The overlap is thus formed by a cylindrical receptacle for the control slide seat. The overlap length and the gap are designed so that minimal leakage occurs between the two connections when the control slide is briefly lifted.

[0015] If a radial bore is provided in the valve housing, which forms the high-pressure connection, the housing-side overlap section is arranged between the seat ring of the valve housing and the radial bore.

[0016] A through-cutout can be provided in the control slide valve, by which two opposite end faces of the control slide valve are connected to one another. The low-pressure connection on the end face is connected to the spring chamber via the through-cutout. For manufacturing reasons, the through-cutout is preferably concentric.

[0017] The control pressure can hold the cartridge valve open. The cartridge valve closes by disconnecting the control pressure. A fast closing time is achieved by making the through-hole in the control slide valve—preferably the central bore—as narrow as possible. This allows for a fast exchange of fluid and pressure between the low-pressure connection and the spring chamber.

[0018] The radius of the through-cutout at its narrowest point is, for example, at least 45% (preferably at least 50%) of the radius of the control slide at the same point. This reduces the mass of the control slide, which facilitates rapid closing.

[0019] The cartridge valve can be a non-return valve preloaded by a spring. The narrowest part of the through-recess is then preferably formed by an inner radial shoulder, which extends inwards and through which the spring acts on the control slide valve with a closing force.

[0020] Adhesion of the control slide to the valve block or the cover and thus delayed switching are avoided by a contact surface for the open position that is as small as possible, which is smaller than the annular cross section of the control slide in the spring region.

[0021] To (further) reduce the mass, the control slide can also be shut off. In this case, a section of a through-cut recess is formed between the inner radial shoulder and the seat ring of the control slide, the radius of which is, for example, at least 65% (preferably at least 70%) of the radius of the control slide at the same point. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings show an embodiment of a fast-switching 2 / 2-way valve according to the invention. The drawings show:

[0023] Figure 1 A first embodiment of a fast-switching 2 / 2-way cartridge valve according to the invention is shown in longitudinal section.

[0024] Figure 2 Shown Figure 1 , having an overlapping portion, and

[0025] Figure 3 Shown Figure 1 A cut-off portion having a damping portion. DETAILED DESCRIPTION

[0026] Figure 1 A fast-switching 2 / 2-way cartridge valve is shown in longitudinal section, which has a control slide 2 for the valve (in Figure 1The control slide valve 2 is shown essentially rotationally symmetrically with respect to the longitudinal axis 4 and is shown here at its ( Figure 1 lower center) in the closed position.

[0027] The control slide valve 2 is designed as a bushing and is guided in a valve bore of a valve housing 6. Figure 1 The end section 22 is inserted into the valve block 8, in which the control pressure line 10 is constructed. In addition, the valve block 8 also forms the valve hole (in Figure 1 In the upper middle part, the control slide valve 2 is guided in the valve hole.

[0028] The cartridge valve is opposite to the valve block 8 (at Figure 1 The lower center end section has a seat region 12 which blocks the high-pressure connection HD from the low-pressure connection ND in the closed position of the control slide 2. The high-pressure connection HD is formed as a radial hole star with a plurality of radial holes 14 in the valve housing 6, wherein Figure 1 Only two radial holes 14 are shown. The low-pressure connection ND is formed as a bushing-shaped valve housing 6 (in Figure 1 An opening on the lower middle side.

[0029] Figure 2 The seat area 12 is shown in the enlarged view A. It can be seen that the seat ring 12a on the control slide valve side and the seat ring 12b on the valve housing side are arranged in the seat area 12. Figure 1 and Figure 2 In the closed position shown they are pressed against each other. The two seat rings 12a, 12b are of frustoconical shape.

[0030] exist Figure 1 As shown in FIG, a spring 16 is arranged to a large extent inside the control slide valve 2 and the valve block 8. More precisely, a spring chamber 18 is provided for the spring 16, which is largely defined by the control slide valve 2 and to a lesser extent by the valve block 8. The spring 16 is supported on ( Figure 1 The control slide 2 is preloaded into the closed position by a radial shoulder 20 on the inside of the control slide 2 .

[0031] Figure 3 An enlarged detail B of the end section 22 of the valve housing 6 is shown, which has a reduced outer diameter and is inserted into the valve block 8 for centering purposes and sealed therewith by a seal 24. The valve block 8 and the sleeve-like valve housing 6 thus jointly form the aforementioned valve opening for the control slide 2.

[0032] The damping element 1 according to the invention is formed on an end section 22 having a reduced outer diameter. For this purpose, a frustoconical inner housing section 26 of the end section 22 cooperates with a likewise frustoconical outer housing section 28 of the control slide 2 .

[0033] The two frustoconical housing sections 26 , 28 have the same (small) inclination or steepness with respect to the longitudinal axis 4 . This inclination or steepness is, for example, <7 degrees. The housing sections 26 , 28 are arranged such that their respective smaller diameter points toward the seat region 12 , while their respective larger diameter points toward the valve block 8 .

[0034] Preferably, the two housing sections 26, 28 (such as Figure 3 The control pressure chamber 30 extends from a control pressure chamber formed on the outer circumference of the control slide 2 to an end face 32 of the end section 22 of the valve housing 6 , on which the control pressure chamber 30 is also arranged.

[0035] When the control slide valve 2 is Figure 3 The closed position shown, in which the two housing sections 26, 28 form only a minimal truncated cone-shaped gap, is ( Figure 3 When the control slide 2 is moved (upward in the middle) into the open position, the gap between the two housing sections 26 , 28 increases, and the control pressure chamber 43 is filled with pressure medium from the control pressure chamber 30 . During the closing process, the control pressure chambers 43 and 30 are initially connected to each other, allowing fluid to flow unimpeded from the control pressure chamber 43 via the control pressure chamber 30 and through the control pressure line 10 . After approximately 60%-70% of the stroke, the conical section of the control slide 2 moves into the conical section of the valve housing 6 , creating a damping gap that continuously narrows and lengthens during further closing. Consequently, the damping gap is at its narrowest shortly before the control slide 2 impacts, and an increasing counterpressure builds up in the control pressure chamber 43, which dampens the impact of the control slide 2 . Advantageously, the damping element can be designed so that its effect is greatest when the control slide 2 moves into the overlap section 34 . Therefore, the closing speed (and thus the collision energy) of the control slide valve 2 is reduced only when the high-pressure region HD is largely separated from the low-pressure region ND by the overlap 34 / 36 .

[0036] Depending on the desired damping effect, the two housing sections 26, 28 are arranged along the cartridge valve ( Figure 1 The length of the longitudinal axis 4 (shown), the mentioned angles of the two truncated cone-shaped housing sections 26, 28 and the position of the control slide valve 2 in FIG. Figure 3 The gap remaining in the closed position shown in FIG can be designed in different ways.

[0037] According to a different embodiment, the two housing sections 26 , 28 forming the damping part 1 can also be of cylindrical design.

[0038] Figure 2 The overlap in the seat region 12 is shown, which is achieved by a cylindrical receptacle for the end section of the control slide 2. This cylindrical receptacle, which can also be referred to as a valve housing-side overlap section 34, interacts with a corresponding control slide-side overlap section 36 and thus forms an overlap. This ensures that during rapid closing of the cartridge valve, when the control slide 2 is lifted from the valve housing-side seat ring 12b for only a short time, minimal or no leakage occurs between the two connections HD, ND.

[0039] Figure 1 The through-recess 38 is shown, which is enlarged compared to the prior art and, in the illustrated embodiment, extends concentrically with the longitudinal axis 4 and extends completely through the control slide 2. The spring chamber 18 is connected to the low-pressure port ND via the through-recess 38. The through-recess 38 has a narrowest point defined by a radial shoulder 20, the radius of which is at least 50% of the radius of the control slide 2 (at the same point). The radial shoulder 20 separates the spring chamber 18 from a section 40 of the through-recess 38 that extends from the narrowest point 38 to the seat region 12.

[0040] The cross section (perpendicular to the longitudinal axis 4 ) of the section 40 of the through-recess 38 is significantly enlarged in this region compared to the cross section of the prior art. This reduces the mass of the control slide 2 , which significantly facilitates rapid and reliable closing of the control slide 2 .

[0041] Furthermore, a circular annular contact surface 42 is formed on the end side of the end section of the control slide 2 facing away from the seat region 12, said contact surface 42 being located at the end of the control slide 2 (at the Figure 1 In the opened position of the cartridge valve (not shown) Figure 1 The contact surface is attached to the cover (also not shown in the figure), and the contact surface facilitates the detachment of the control slide valve 2 from the cover during a rapid closing movement.

[0042] A fast-switching 2 / 2-way cartridge valve is disclosed, which can be used as a check valve. The closing movement of the closing body of the 2 / 2-way cartridge valve is damped by abutment sections that abut against one another and can move relative to one another during the closing movement. The abutment sections are formed on the closing body on the one hand and on the valve opening in which the closing body is guided on the other hand.

Claims

1. A fast-switching 2 / 2-way valve in the form of a seat valve, comprising a valve housing (6) in which a seat ring (12b) is formed for a control slide valve (2) guided in the valve housing (6), characterized in that: A damping portion (1) for the closing movement of the control slide valve (2) is formed by means of an outer housing section (28) of the control slide valve (2) and an inner housing section (26) of the valve housing (6), wherein a control pressure chamber (43) is formed between the control slide valve (2) and the valve housing (6), and wherein a counterpressure is built up in the control pressure chamber (43) during the closing process, which counterpressure has a damping effect on the impact of the control slide valve (2). 2 . The cartridge valve according to claim 1 , which is a check valve.

3. The cartridge valve according to claim 1 or 2, wherein the valve housing (6) is bushing-shaped or tubular or is at least partially a bushing or a tube, characterized in that The inner housing section (26) is formed on an end section (22) of the valve housing (6), which is opposite the seat area (12) of the cartridge valve.

4. The cartridge valve according to claim 1 or 2, wherein the two housing sections (26, 28) of the damping part (1) are conical.

5. The cartridge valve according to claim 1 or 2, wherein the two housing sections (26, 28) of the damping part (1) are cylindrical.

6. The cartridge valve according to claim 1 or 2, comprising an overlap between the valve housing (6) and the control slide valve (2), which overlap has a closing or blocking effect between the high-pressure connection (HD) and the low-pressure connection (ND).

7. The cartridge valve according to claim 6, wherein the seat ring of the valve housing (6) and the seat ring (12a) of the control slide valve (2) are conical, characterized in that The overlap is formed by an overlap section (36) on the control slide side adjacent to the seat ring (12a) of the control slide valve (2) and by an overlap section (34) on the valve housing side adjacent to the seat ring (12b) of the valve housing (6).

8. The cartridge valve according to claim 7, wherein a radial bore (14) is provided in the valve housing (6), which forms the high-pressure connection (HD), characterized in that The valve housing-side overlap section (34) is arranged between a seat ring (12b) of the valve housing (6) and the radial bore (14).

9. The cartridge valve according to claim 1 or 2, wherein a through-recess (38) is provided in the control slide valve (2), and two mutually opposite end sides of the control slide valve (2) are connected to each other via the through-recess. 10 . The cartridge valve according to claim 9 , wherein the radius of the through-cut recess ( 38 ) at its narrowest point is at least 45% of the radius of the control slide ( 2 ).

11. A cartridge valve according to claim 10, wherein the narrowest part of the through-recess (38) is formed by an inner radial shoulder (20), which extends inwardly and through which a spring (16) loads the control slide valve (2) with a closing force.

12. A cartridge valve according to claim 11, wherein a section (40) of the through-recess (38) is formed between the inner radial shoulder and the seat ring (12a) of the control slide valve (2), the radius of which section is at least 60% of the radius of the control slide valve (2).

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