Electric valve

Abstract

Provided is an electric valve comprising a rotary-type valve body, with which foreign matter in a cooling solution can be prevented from obstructing rotation of the valve body even when foreign matter infiltrating between an outer wall of the valve body and a housing inner wall, and any increase in size can be minimized.　The present invention comprises a housing 11 having an opening at one end and a communication port on the outer periphery, a valve body 12 that is rotatably inserted into the housing and that opens / closes the communication port, a seal member 14 attached to the communication port and brought into sliding contact with the outer periphery of the valve body, and a drive device that rotationally drives the valve body. The valve body has a cylindrical valve part. Formed in the valve part are an outer wall capable of closing off the communication port, a valve hole of communicating with the communication port, a valve opening that is formed at one end of the valve part and that communicates with the opening, and a foreign matter recovery part 12h. The foreign matter recovery part is a groove or a hole formed in a non-seal area which is at the outer periphery of the valve part and on which the seal member does not slide.

Description

Motor-operated valve

[0001] The present invention relates to a motor-operated valve.

[0002] For example, rotary flow control valves used in automotive cooling systems include a valve housing that houses a cylindrical valve element with a spherical or straight outer wall that can be rotated from the outside. This rotary flow control valve uses a spherical or cylindrical valve element, and is configured to open and close a passage connected to a valve chamber in the valve housing as desired by rotating the valve element to open or close the passage.

[0003] The inner wall of the valve chamber in the valve housing is formed along the outer wall of the valve disc, and the distance between the outer wall of the valve disc and the inner wall of the housing is constant in the circumferential direction. However, if foreign matter in the coolant inside the valve housing becomes caught between the outer wall of the valve disc and the inner wall of the housing or if the foreign matter remains there, there is a risk that the rotation of the valve disc will be hindered. There is also a risk that the load torque required to drive the valve disc and the pressure loss resistance will increase.

[0004] In response to this problem, the invention disclosed in Patent Document 1 discloses a structure in which the radial cross section of the inner wall 201a of the housing 201, which rotatably houses the valve element 200, is polygonal, as shown in Figure 4. That is, the inner wall 201a of the housing 201 is formed so that the distance from the rotation axis 205 varies in the circumferential direction. Therefore, if foreign matter M in the coolant gets between the outer wall 200a of the valve element 200 and the inner wall 201a of the housing 201, the foreign matter M will move into a large gap 206 as the valve element 200 rotates around the axis. This reduces the possibility of impeding the rotation of the valve element 200.

[0005] Japanese Patent Application Laid-Open No. 2019-211069

[0006] However, when the radial cross-sectional shape of the inner wall 201a of the housing 201 is made polygonal as in the structure of the invention disclosed in Patent Document 1, and a gap 206 is provided between the housing 201 and the valve body 200 to allow foreign matter M to escape, there is a problem that the electric valve becomes larger.

[0007] The present invention has been made with attention to the above-mentioned points, and aims to provide an electric valve having a rotary valve body that can prevent foreign matter in the coolant from interfering with the rotation of the valve body even if the foreign matter gets between the outer wall of the valve body and the inner wall of the housing, and that can prevent the valve body from becoming larger.

[0008] In order to solve the above-mentioned problems, the electric valve of the present invention comprises a housing having an opening at one end and a communication port on its outer periphery, a valve body that is rotatably inserted into the housing and opens and closes the communication port, a sealing member that is attached to the communication port and slides against the outer periphery of the valve body, and a drive device that rotates the valve body, wherein the valve body has a cylindrical valve portion that is formed with an outer wall that can close the communication port, a valve hole that can communicate with the communication port, a valve opening formed at one end of the valve portion and that slides against the opening, and a foreign matter collection portion, and wherein the foreign matter collection portion is a groove or hole formed in a non-sealed area on the outer periphery of the valve portion where the sealing member does not slide.

[0009] With this configuration, a foreign matter collection section is formed on the outer periphery of the valve section in a non-sealed area where the seal member does not slide. As a result, even if foreign matter in the coolant enters the gap between the inner wall of the housing and the outer wall of the valve disc, the foreign matter can be contained in the foreign matter collection section as the valve disc rotates. This prevents the foreign matter from simultaneously contacting the inner wall of the housing and the outer wall of the valve disc as the valve disc rotates, preventing the foreign matter from impeding the rotation of the valve disc. Furthermore, because the foreign matter collection section that contains the foreign matter is formed on the outer wall of the valve disc, the motor-operated valve can be kept small. Furthermore, because the foreign matter collection section is formed as a groove or hole formed in the valve disc, the edge of the foreign matter collection section can scrape off the foreign matter as the valve disc rotates, resulting in a more effective foreign matter collection than conventional systems.

[0010] It is preferable that the foreign matter collection portion be formed long on the outer wall of the valve portion, from one end to the other in the axial direction along the axis that is the center of rotation of the valve disc. By forming the foreign matter collection portion, which is made up of grooves or holes, long from one end to the other in the axial direction of the rotation of the valve portion, the edge of the foreign matter collection portion that scrapes off foreign matter can be made long. This further enhances the effectiveness of scraping off foreign matter with the edge of the foreign matter collection portion.

[0011] Preferably, the valve body has two or more valve sections connected in the axial direction along an axis that is the center of rotation of the valve body, and the foreign matter collection section formed on the outer valve wall of at least one of the adjacent valve sections is positioned so as to overlap the valve hole formed in the other valve section in the axial direction. By configuring in this manner, foreign matter contained in the foreign matter collection section can be flushed into the valve hole.

[0012] According to the electric valve of the present invention, in an electric valve equipped with a rotary valve body, even if foreign matter in the coolant gets between the outer wall of the valve body and the inner wall of the housing, the foreign matter can be prevented from interfering with the rotation of the valve body and the size can be prevented from increasing.

[0013] Fig. 1 is a cross-sectional view showing an example of the configuration of the motor-operated valve of this embodiment. Fig. 2 is a perspective view of a valve body of a valve element provided in the motor-operated valve of Fig. 1. Fig. 3 is a cross-sectional view taken along the line A-A in Fig. 2. Fig. 4 is a cross-sectional view showing an example of the radial cross-sectional shape of a conventional valve element housing.

[0014] Hereinafter, an embodiment of the motor-operated valve according to the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to this embodiment. Furthermore, in the specification and drawings of the present application, elements that can be similarly described will be given the same reference numerals, and duplicated explanations may be omitted.

[0015] 1 is a cross-sectional view showing an example of the configuration of an electric valve according to one embodiment. In this embodiment, for the sake of convenience, the upper and lower sides in FIG. 1 will be simply referred to as "upper" and "lower".

[0016] The motor-operated valve 1 of this embodiment is used, for example, in an automobile cooling circuit (coolant circulation system) that includes a cooling path through which coolant flowing out of the engine (cylinder head side) returns to the engine (cylinder block side) via a radiator, and a bypass path through which coolant flowing out of the engine returns to the engine without passing through the radiator (bypassing).The motor-operated valve 1 controls the opening and closing of a valve hole formed in the valve body to discharge coolant that has flowed in through the engine into the cooling path and the bypass path, and to control the flow rate.

[0017] <Basic Structure of Motor-Operated Valve> The motor-operated valve 1 of this embodiment includes a housing 11 in which a coolant inlet 11a and multiple outlets 11b (11b1, 11b2) are formed, a valve element 12 housed in the interior space of the housing 11 and rotatable about an axis (rotation axis) within the interior space, adapters 13 (131, 132) connected to the outlet 11b, and seal members 14 (141, 142) for preventing leakage of coolant that passes through valve holes 12f (12f1, 12f2) formed in the valve element 12 and is released toward the adapter 13. This motor-operated valve 1 appropriately releases coolant toward the cooling path and bypass path by controlling the rotation of the valve element 12 in response to instructions from a control device (not shown) installed in the vehicle.

[0018] The structure of the motor-operated valve 1 of this embodiment will be described in more detail below. In this embodiment, the direction along the axis that is the center of rotation of the valve body 12 will be referred to as the "axial direction," the direction perpendicular to the axis will be referred to as the "radial direction," and the direction around the axis will be referred to as the "circumferential direction."

[0019] The housing 11 includes a main body 11c having an internal space (valve body accommodating portion 20) for accommodating the valve body 12, and a bottomed lid 11d that defines a space between the main body 11c and the upper surface thereof for accommodating the reducer 15. The open end (periphery) of the lid 11d is attached to the upper surface of the main body 11c to close the internal space of the lid 11d. The reducer 15 accommodated in the space of the lid 11d includes multiple gears and has the function of reducing the rotation of a motor (drive unit: not shown) that operates in response to commands from a control device and transmitting the reduced rotation to the valve body 12.

[0020] In addition, in the housing 11, a cylindrical insertion tube portion 11e is provided at the top of the main body portion 11c, and rotatably supports the shaft 12a that functions as the rotation axis of the valve body 12 while it is inserted therethrough. A bearing 11f that rotatably supports the upper part of the shaft 12a is provided on the inner periphery of the insertion tube portion 11e.

[0021] Furthermore, in the housing 11, substantially cylindrical outlet ports 11b (11b1, 11b2) serving as communication ports are provided on the outer periphery of the main body portion 11c (inner wall 20a of the valve body accommodating portion 20) and protrude radially outward. The outlet ports 11b1, 11b2 shown in FIG. 1 are provided at different positions in the axial and circumferential directions. Furthermore, cylindrical adapters 13 (131, 132) communicating with the above-mentioned cooling path and bypass path are inserted and fixed into the outlet ports 11b, respectively.

[0022] In Figure 1 (cross-sectional view), outlets 11b are provided in two locations on the main body 11c, but this is not limited to this, and outlets 11b may be formed in locations other than those shown in Figure 1 depending on the number and direction of flow paths for discharging the coolant.

[0023] Furthermore, an inlet 11a, which is an opening communicating with the cylinder head side and through which coolant is introduced into the valve body 12 side, is formed at the lower end of the housing 11. A frame 17 is attached to the inlet 11a and supports the lower end of the shaft 12a with a cylindrical portion 17a formed in the center. Specifically, the frame 17 has an annular frame portion 17b attached to the housing 11 along the periphery of the inlet 11a, the cylindrical portion 17a formed in the center of the frame portion 17b, and multiple bridge portions 17c for frame strength reinforcement that connect the cylindrical portion 17a to multiple points (equally spaced) of the frame portion 17b. The coolant is able to flow into the housing 11 through the frame 17.

[0024] <Valve element> The valve element 12 has a shaft 12a that functions as a rotation axis, and a valve body 12b that has an outer wall that can switch its communication state with the outside and is joined to the shaft 12a so as to be rotatable together with the shaft 12a. A gear that is a component of the speed reducer 15 is integrally attached to the shaft 12a. As a result, when the gear is rotated by the drive of the motor, the valve element 12 (shaft 12a, valve body 12b) rotates integrally with the gear.

[0025] In addition, the valve body 12b of the valve element 12 has a central joint 12c that is joined to the outer periphery of the shaft 12a with the shaft 12a passing through it. The valve body 12b is cylindrical and has upper and lower valve openings, and has a structure in which two valve portions with spherical outer walls are connected to each other. The valve openings communicate with the inlet 11a (opening) of the housing 11. In this embodiment, one valve portion formed at the bottom is referred to as the first valve portion 12b1, and the other valve portion formed above it is referred to as the second valve portion 12b2.

[0026] More specifically, the valve body 12b is made of resin and is formed into a generally cylindrical shape, and is housed within the valve body housing 20. The shaft 12a is located on the central axis of the valve body 12. As shown in Fig. 2, the valve body 12b of the valve body 12 has a first valve portion 12b1 that opens upward and downward, and a second valve portion 12b2 that also opens upward and downward and is formed to communicate in the axial direction from one end (the upper end in the figure) of the first valve portion 12b1. As shown in Fig. 1, the valve body 12b has a coolant communication passage R formed therein by the first valve portion 12b1 and the second valve portion 12b2, and which communicates with the inlet 11a (opening).

[0027] As shown in the figure, outer walls 12m, 12n (valve outer walls) of the first valve portion 12b1 and the second valve portion 12b2 are formed in a spherical shape (so-called ball valve) with the largest diameter at the axial center, and valve portion inner walls 12i, 12j that form a communication passage R through which the coolant passes are formed parallel to the axial direction. Furthermore, the inner wall 20a of the valve element accommodating portion 20 is formed along the shapes of the outer walls 12m, 12n of the first valve portion 12b1 and the second valve portion 12b2, and the gap distance between the inner wall 20a and the outer walls 12m, 12n is formed to be approximately constant in the circumferential direction.

[0028] Additionally, within the second valve portion 12b, for example, three reinforcing members 45 are evenly arranged in the circumferential direction to reinforce the valve body 12. These reinforcing members 45 are designed not to interfere with the insertion cylindrical portion 11e. The shaft 12a is guided by the insertion cylindrical portion 11e and rotates integrally with the valve body 12b.

[0029] A seal ring 12d closes the gap between the shaft 12a and the insertion tube portion 11e of the housing 11. This prevents the coolant in the main body portion 11c from flowing from the insertion tube portion 11e into the lid portion 11d. The lower end opening of the first valve portion 12b1 functions as an inlet 12e that takes in the coolant flowing in from the cylinder head side through the frame 17 (inlet port 11a) into the internal space of the valve body 12.

[0030] The first valve portion 12b and the second valve portion 12b are provided with valve holes 12f and 12f, respectively. The valve holes 12f extend radially through the first valve portion 12b and the second valve portion 12b. When the valve element 12 rotates and the valve holes 12f overlap the openings of the seal member 14, coolant flows out from the overlapping portions. As described above, each valve hole 12f opens and closes as the valve body 12b rotates in conjunction with the rotation of the shaft 12a. This opening and closing action switches the communication state between the inlet 11a and the outlet 11b (11b, 11b). In other words, each valve hole 12f provided in the valve element 12 is configured to switch the communication state between the corresponding outlet 11b (11b, 11b) and the internal space of the valve element 12 as the valve element 12 rotates. As a result, the coolant taken into the internal space of the valve body 12 (first valve portion 12b1, second valve portion 12b2) through the inlet 12e is released toward the cooling path and the bypass path in accordance with the opening and closing operation of each valve hole 12f, and the flow rate is controlled.

[0031] As shown in Figures 2 and 3, the valve element 12 according to this embodiment includes a groove 12h, which serves as a foreign matter collection section and is formed with a predetermined width W in the circumferential direction and extends axially in an area of ​​the outer wall 12m of the first valve portion 12b where the valve hole 12f is not formed, outside the area used for sealing the outlet 11b (i.e., the non-sealed area where the seal member 14 does not slide). In this embodiment, the groove 12h is formed in the outer wall 12m of the first valve portion 12b at a position overlapping with the valve hole 12f formed in the second valve portion 12b in the rotational axis direction. The axial length dimension H of the groove 12h extends from one end (upper end) of the first valve portion 12b to the other end (lower end) of the first valve portion 12b. The deepest portion of the groove 12h has a predetermined dimension D.

[0032] As described above, the inner wall 20a of the valve element accommodating portion 20 is formed to follow the shapes of the outer walls 12m, 12n of the first valve portion 12b1 and the second valve portion 12b2, and the gap distance between the inner wall 20a and the outer walls 12m, 12n is formed to be approximately constant in the circumferential direction. Therefore, if foreign matter M in the coolant enters the gap between the inner wall 20a and the outer wall 12m, there is a risk that the foreign matter M will not be able to be discharged. Therefore, by providing the groove 12h as shown in Figure 3, the foreign matter M can be accommodated in the groove 12h as the valve element 12 rotates.

[0033] Furthermore, the groove 12h may be formed at a position that overlaps with the valve hole 12f formed in the second valve portion 12b in the axial direction, in which case foreign matter M accommodated in the groove 12h can be channeled into the valve hole 12f. Even if the foreign matter M remains accommodated in the groove 12h, the foreign matter M can be prevented from simultaneously contacting the inner wall 20a of the valve body accommodating portion 20 and the outer wall 12m of the first valve portion 12b as the valve body 12 rotates, thereby preventing the foreign matter M from impeding the rotation of the valve body 12.

[0034] Although not shown, a groove similar to the groove 12h may be formed in an area of ​​the outer wall 12n of the second valve portion 12b where the valve hole 12f is not formed, outside the area used to seal the outlet 11b. In this case, the groove may be formed in the outer wall 12n of the second valve portion 12b at a position that axially overlaps with the valve hole 12f formed in the first valve portion 12b.

[0035] According to the above configuration, by providing a groove in the second valve portion 12b, even if foreign matter M in the coolant enters the gap between the inner wall 20a and the outer wall 12n on the second valve portion 12b side, the foreign matter M can be contained in the groove as the valve element 12 rotates. Furthermore, when a groove is provided in the second valve portion 12b, if the groove is formed at a position that axially overlaps with the valve hole 12f1 formed in the first valve portion 12b1, the foreign matter M can be channeled into the valve hole 12f1. Furthermore, even if the foreign matter M remains contained in the groove, the foreign matter M is prevented from simultaneously contacting the inner wall 20a of the valve element accommodating portion 20 and the outer wall 12n of the second valve portion 12b2 as the valve element 12 rotates, thereby preventing the foreign matter M from impeding the rotation of the valve element 12.

[0036] As described above, according to this embodiment, a groove 12h serving as a foreign matter collection portion is formed on the outer periphery of the first valve portion 12b (second valve portion 12b) in a non-sealed region where the seal member 14 does not slide, from one axial end to the other. This allows foreign matter M in the coolant to enter the gap between the inner wall 20a of the valve element accommodating portion 20 and the outer wall 12m (12n) of the valve element 12, and the foreign matter M can be contained in the groove 12h as the valve element 12 rotates. This prevents the foreign matter M from simultaneously contacting the inner wall 20a of the valve element accommodating portion 20 and the outer wall 12m (12n) of the first valve portion 12b (second valve portion 12b) as the valve element 12 rotates, thereby preventing the foreign matter M from interfering with the rotation of the valve element 12. Furthermore, because the groove 12h for containing foreign matter is formed in the outer wall of the valve element 12, the motor-operated valve can be prevented from becoming larger. Furthermore, because the groove 12h is formed long from one end to the other in the axial direction of the first valve portion 12b1 (second valve portion 12b2), the edge of the long groove 12h can scrape off foreign matter as the valve element 12 rotates, thereby improving the foreign matter collection effect.More preferably, the groove 12h is formed in a position that overlaps with the valve hole 12f2 (valve hole 12f1) formed in the second valve portion 12b2 (first valve portion 12b1) in the axial direction, allowing foreign matter M contained in the groove 12h to flow into the valve hole 12f2 (valve hole 12f1).As such, according to one embodiment of the present invention, foreign matter M is not hindered from rotating the valve element 12, thereby improving controllability and durability.

[0037] In this embodiment, the bottom of the groove 12h is formed flat, but the present invention is not limited to this and may have a curved shape that follows the surface shape of the outer wall 12m. In this case, the depth of the groove 12h can be constant. In this embodiment, the groove 12h has a U-shaped cross section as shown in FIG. 3 , but the cross-sectional shape of the groove 12h is not limited to this. In this embodiment, the foreign matter collection portion is described as the groove 12h, but the present invention is not limited to this and may also have a hole (a bottomed hole or a through hole) formed in the outer wall 12m.

[0038] Furthermore, in this embodiment, the valve element 12 in which the first valve portion 12b1 and the second valve portion 12b2 are axially connected has been described as an example, but the valve element according to the present invention is not limited to this configuration. For example, the number of valve portions may be one, or three or more valve portions may be connected in the rotational axis direction. When three or more valve portions are connected in the rotational axis direction, the groove portion 12h formed in the valve outer wall of at least one of the adjacent valve portions may be positioned so as to overlap the valve hole formed in the other valve portion in the rotational axis direction. Furthermore, in this embodiment, the valve element 12 in which the outer wall is spherical (a so-called ball valve) has been described, but the present invention is not limited to this configuration and may also be a valve element having a cylindrical outer wall surface.

[0039] Furthermore, in this embodiment, as an example, the electric valve 1 that discharges the coolant that flows in from the inlet 11a (on the frame 17 side) toward the cooling path and the bypass path has been described, but the connection configuration of the flow path that communicates with the electric valve 1 is not limited to this and can be changed as appropriate depending on the specifications of the automobile's cooling circuit (coolant circulation system) (for example, a flow path that flows from the inlet (upstream side) formed on the outer periphery of the main body portion 11c of the housing 11 (inner wall 20a of the valve body accommodating portion 20) to the outlet (downstream side) on the frame 17 side).

[0040] Furthermore, in this embodiment, the sealing members 14 (141, 142) are pressed against the outer wall of the valve body 12 by the biasing force of the coil spring as shown in FIG. 1, but this is not limited to this, and any other structure may be used as long as it can prevent leakage of the coolant that passes through the valve hole 12f of the valve body 12 and is discharged to the adapter 13 side.

[0041] Although the preferred embodiments of the present invention have been described in detail above, modifications, variations and changes can be made thereto without departing from the scope of the appended claims.

[0042] REFERENCE SIGNS LIST 1 Motor-operated valve 11 Housing 11b Outlet (communication port) 12 Valve element 12a Shaft 12b1 First valve portion (valve body) 12b2 Second valve portion (valve body) 12f1 Valve hole 12f2 Valve hole 12m Outer wall (valve outer wall) 12h Groove portion (foreign matter collection portion) 14 Seal member 20 Valve element accommodating portion 20a Inner wall R Communication passage

Claims

1. An electrically operated valve comprising: a housing having an opening at one end and a communication port on its outer periphery; a valve body rotatably inserted into said housing for opening and closing said communication port; a sealing member attached to said communication port and in sliding contact with the outer periphery of said valve body; and a drive device for rotating said valve body, wherein said valve body has a cylindrical valve portion, said valve portion being formed with an outer wall capable of closing said communication port, a valve hole capable of communicating with said communication port, a valve opening formed at one end of said valve portion and communicating with said opening, and a foreign matter collection portion, wherein said foreign matter collection portion is a groove or hole formed in a non-sealed area on the outer periphery of said valve portion with which said sealing member does not slide.

2. The motor-operated valve as described in claim 1, characterized in that the foreign matter collection section is formed in a long length on the outer wall of the valve section, extending from one end to the other in the axial direction along the axis that is the center of rotation of the valve body.

3. The motor-operated valve as described in claim 1, characterized in that two or more of the valve sections of the valve body are connected in the axial direction along an axis that is the center of rotation of the valve body, and the foreign matter collection section formed on the outer valve wall of at least one of the adjacent valve sections is located in a position that overlaps with the valve hole formed in the other valve section in the axial direction.

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