Electric valve

Abstract

Provided is an electric valve wherein a cooling liquid is prevented from rapidly flowing out to an outflow port when a valve body rotates and the cooling liquid outflow port and a valve hole communicate with each other, the microflow rate of the cooling liquid is controlled, and clogging by foreign matter is minimized.　The electric valve includes a housing 11 that has an opening at one end and a communication port 11b in a peripheral surface, a valve body 12 that is rotatably inserted into the housing and that opens and closes the communication port, a cylindrical seal member 14 that is attached to the communication port and that slides on the peripheral surface of the valve body, and a drive device that rotatably drives the valve body. The valve body has a cylindrical valve main body 12b, and formed in the valve body are an outer wall that can close off the communication port, a valve hole that can communicate with the communication port, and a valve opening that is formed at one end of the valve body and that communicates with the opening. In the cylindrical seal member, one end part of the seal member in which an opening is formed slides against a peripheral surface of the valve body, and a groove part 14c connected to the opening is formed in the one end part of the seal member.

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 (valve housing portion) that houses a cylindrical valve element with a spherical or straight outer wall so that it can be rotated from the outside. This rotary flow control valve uses a spherical or cylindrical valve element, and is configured to perform the desired operation by appropriately opening and closing an outlet to a passage connected to the valve housing through rotation of the valve element. That is, a valve hole is formed in the side of the valve element, and rotation of the valve element aligns the valve hole with the position of an outlet formed on the inner surface of the valve housing, allowing the coolant to flow through the outlet.

[0003] In such a flow control valve, the communication state between the outlet and the valve hole is switched by rotating the valve disc. If the communication state is switched abruptly by rotating the valve disc, the flow rate of the coolant flowing through the outlet changes abruptly, which tends to cause large pressure fluctuations and temperature changes on the outlet side. To address this issue, Patent Document 1 discloses a structure that gradually increases the amount of coolant flowing in from the valve hole side, such as at the beginning of communication between the outlet and the valve hole.

[0004] 6, the flow control valve disclosed in Patent Document 1 has a slit 52a penetrating the peripheral wall portion, formed on the front side in the rotational direction of the valve body 50, of the edge of a valve hole 52 formed in a peripheral wall portion 51 of a cylindrical valve body 50. The slit 52a extends from the valve hole 52 along the rotational direction of the valve body 50, and guides the coolant in the inner region of the valve body 50 to the outlet through the slit 52a, before the outlet directly communicates with the valve hole 52.

[0005] JP 2016-138452 A

[0006] However, when a slit 52a is formed at the edge of the valve hole 52, penetrating the wall, as disclosed in Patent Document 1, the width of the slit becomes narrow when attempting to pass a minute flow rate, which raises the risk of foreign matter clogging the slit.

[0007] The present invention has been made with attention to the above points, and aims to provide an electric valve that can prevent the coolant from suddenly flowing out of the outlet when the valve body rotates and the coolant outlet and the valve hole are connected, can control the minute flow rate of the coolant, and can suppress clogging by foreign matter.

[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 circumferential surface, a valve body that is rotatably inserted into the housing and opens and closes the communication port, a cylindrical sealing member that is attached to the communication port and slides against the circumferential surface of the valve body, and a drive device that rotates the valve body, wherein the valve body has a cylindrical valve body, and the valve body is formed with an outer wall that can close the communication port of the housing, a valve hole that can communicate with the communication port, and a valve opening that is formed at one end of the valve body and communicates with the opening of the housing, and the cylindrical sealing member is characterized in that one end of the sealing member where the opening is formed slides against the circumferential surface of the valve body, and one end of the sealing member is formed with a groove portion that leads to the opening.

[0009] With this configuration, in the motor-operated valve, the groove initially overlaps with the valve hole as the valve element rotates, and the coolant begins to flow from the groove to the communication port (outlet). This prevents the coolant from suddenly flowing out of the communication port and allows for the control of the minute flow rate of the coolant. Furthermore, since this configuration does not require the coolant to flow through a narrow slit as in the conventional valve, clogging by foreign matter can be suppressed.

[0010] Furthermore, it is desirable that at least a region of the one end of the sealing member where the opening is formed, that is radially outward of the groove, is formed so as to be able to slide against the circumferential surface of the valve body. With this configuration, it is possible to prevent a decrease in sealing effect when the valve hole and the communication port do not overlap.

[0011] Furthermore, it is desirable that the seal member has a concave or convex engaging portion formed on the outer circumferential surface of the seal member, which engages with a convex or concave portion formed on the communication port side. By providing the rotation-preventing engaging portion on the outer circumferential surface of the seal member in this manner, it is possible to prevent the seal member from rotating in the circumferential direction.

[0012] The electric valve of the present invention prevents the coolant from suddenly flowing out of the outlet when the valve body rotates and the coolant outlet and the valve hole are connected, and can control the minute flow rate of the coolant, thereby suppressing clogging by foreign matter.

[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 provided in the motor-operated valve of Fig. 1. Fig. 3 is a perspective view of a seal member of this embodiment. Fig. 4 is a cross-sectional view of the seal member of Fig. 3. Fig. 5(a) is a plan view of a groove portion of the seal member of Fig. 3, and Fig. 5(b) is a plan view showing a modified example of the groove portion. Fig. 6 is a front view showing the shape of a conventional valve hole.

[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 intended for use in an automobile cooling circuit (coolant circulation system) that includes, for example, 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 having a coolant inlet 11a and a plurality of coolant outlets 11b (11b1, 11b2), a valve element 12 accommodated in the interior space of the housing 11 and rotatable about its axis within the interior space, adapters 13 (131, 132) connected to the outlets 11b, and a valve hole 12f (12f １ , 12f ２ ) and is discharged to the adapter 13 side. This motor-operated valve 1 controls the rotation of the valve body 12 in response to instructions from a control device (not shown) mounted on the vehicle, thereby appropriately discharging the coolant, for example, toward the cooling path and the bypass path.

[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] In the housing 11, a generally cylindrical outlet port 11b (11b1, 11b2) serving as a communication port is provided on the circumferential surface of the main body portion 11c (the inner wall 20a of the valve body accommodating portion 20) and protrudes 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 cooling path and bypass path described above 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 is formed at the lower end of the housing 11. The inlet 11a is an opening that communicates with the cylinder head side and allows coolant to enter the valve body 12 side. A frame 17 is attached to the inlet 11a. A cylindrical portion 17a formed in the center of the frame 17 rotatably supports the lower end of the shaft 12a. The coolant can 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 together with the gear.

[0025] In addition, the valve body 12b of the valve element 12 has a central joint 12c (rotation shaft holding portion) that is joined to the outer periphery of the shaft 12a with the shaft 12a passing through it. The valve body 12b has two cylindrical valve portions with upper and lower valve openings and spherical outer walls, arranged vertically and vertically. 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 element 12 is made of resin and is formed into a generally cylindrical shape and is housed in the valve element housing 20. The shaft 12a is located on the central axis of the valve element 12. FIG. 2 is a perspective view of the valve element 12. As described above, the valve body 12b of the valve element 12 has a first valve portion 12b1 that opens vertically and a second valve portion 12b2 that also opens vertically and is formed to communicate in the axial direction from one end (the upper end in FIG. 1) of the first valve portion 12b1. The valve element 12 has a coolant communication passage R formed therein by the first valve portion 12b1 and the second valve portion 12b2 and communicating with the inlet 11a (opening).

[0027] The outer wall 12m of the first valve portion 12b1 is connected and supported by a plurality of (e.g., three) bridges (not shown) between the outer wall 12m and the joint 12c where the outer periphery of the shaft 12a is joined, in order to obtain a desired strength. In the first valve portion 12b1, the communication passage R serves as a flow path for the coolant passing between the plurality of bridges.

[0028] As shown in the figure, the 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 the valve portion inner walls 12i, 12j that form the communication passage R through which the coolant passes are formed parallel to the axial direction.

[0029] 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.

[0030] 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.

[0031] 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, the coolant flows out from the overlapping portions. Thus, 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). That is, each valve hole 12f provided in the valve element 12 is configured so that the communication state between the corresponding outlet 11b (11b, 11b) and the internal space of the valve element 12 is switched 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 outflow amount is controlled.

[0032] The communication structure between the valve holes 12f and 12f and the outlet 11b will now be described in more detail. A seal member 14 (14, 14) is interposed between the valve body 12 and a cylindrical adapter 13 (13, 13). FIG. 3 is a perspective view of the seal member 14, and FIG. 4 is a cross-sectional view of the seal member 14. As shown, the seal member 14 is a cylindrical body consisting of a large-diameter portion 14A (first cylindrical portion) and a small-diameter portion 14B (second cylindrical portion) with different diameters. The small-diameter portion 14B is inserted into the end of the adapter 13. As shown in FIG. 1, one end of a coil spring 19 (19, 19) provided within the adapter 13 abuts against the end of the small-diameter portion 14B. The biasing force of the coil spring 19 presses the seal member 14 against the outer wall 12m (12n) of the valve body 12.

[0033] 1, the large diameter portion 14A has an opening 14A1 at one end, and one end 14A2 of the large diameter portion 14A where this opening 14A1 is formed is in sliding contact with the circumferential surface of the valve body 12, i.e., the outer wall 12m (12n), to prevent leakage of the coolant to be discharged toward the adapter 13. In addition, the circumferential surface (outer walls 12m, 12n) of the valve body 12 is provided with a plurality of valve holes (12f1, 12f2) that are individually formed corresponding to the outlet 11b so as to overlap with the outlet 11b upon axial rotation.

[0034] If the communication state is suddenly switched when one end 14A2 of the seal member 14 overlaps with the valve holes (12f, 12f) of the valve disc 12 due to rotation of the valve disc 12, the flow rate of the coolant flowing through the outlet 11b changes suddenly, which tends to result in large pressure and temperature fluctuations on the outlet 11b side. Therefore, in this embodiment, as shown in Figures 3 and 4, a bottomed groove 14C is provided radially in the one end 14A2 of the large-diameter portion 14A of the seal member 14 at a position that first overlaps with the valve holes 12f, 12f as the valve disc 12 rotates. Furthermore, at least a region 14A21 of the one end 14A2 of the seal member 14 radially outward of the groove 14C is formed to be able to slide against the outer wall 12m (12n) of the valve disc 12, so that the sealing effect is not reduced when the opening 14A1 does not overlap with the valve holes 12f, 12f.

[0035] The shape of the groove 14C may be a sector shape in which the groove side surfaces 14C1 and 14C2 widen radially inward, as shown in the plan view of FIG. 5( a), or a shape in which the distance between the groove side surfaces 14C1 and 14C2, i.e., the width, is constant in the radial direction, as shown in the plan view of FIG. 5( b). The groove bottom surface 14C3 may have a surface shape inclined at a predetermined angle relative to the radial direction or a surface shape perpendicular to the axial direction. The depth of the groove back surface 14C4 may be set arbitrarily. The design of these groove shapes may be determined depending on the required specifications, control method, etc.

[0036] By forming the groove portion 14C in the one end portion 14A2 where the opening 14A1 of the sealing member 14 that contacts the valve body 12 is formed in this manner, the flow of cooling liquid into the outlet 11b at the start of communication is slowed down, sudden pressure fluctuations are suppressed, and the flow rate of cooling liquid supplied to the outlet 11b can be changed with precision.

[0037] As described above, the groove 14C is located at the end 14A2 of the large-diameter portion 14A of the seal member 14, where the opening 14A1 of the large-diameter portion 14A is formed, at a position that initially overlaps with the valve holes 12f1 and 12f2 as the valve disc 12 rotates. However, if the seal member 14 rotates relative to the adapter 13, it will be difficult to smooth the flow of coolant into the outlet 11b when the valve holes 12f1 and 12f2 begin to communicate with the inlet 11a. Therefore, in this embodiment, as shown in FIG. 3, an anti-rotation engagement groove 14D (engagement portion) is provided on the outer circumferential surface of the small-diameter portion 14B. Meanwhile, a rib (protrusion, not shown) that engages with the engagement groove 14D is provided on the inner circumferential surface of the adapter 13 (on the communication port side) into which the small-diameter portion 14B is inserted. This allows the seal member 14 to move axially (toward the valve disc 12) due to the biasing force of the coil spring 19, but prevents circumferential rotation.

[0038] In this configuration, for example, when the valve element 12 is rotated by driving the shaft 12a (rotating shaft) and the valve hole 12f (12f) of the first valve portion 12b (second valve portion 12b) begins to communicate with the outlet 11b (outlet 11b), the coolant flowing in from the engine side first starts to flow from the groove 14C formed on the opening 14A1 side of the seal member 14 (14) to the outlet 11b (outlet 11b). In other words, the flow of coolant into the outlet 11b at the start of communication is gradual, and sudden pressure fluctuations are suppressed. As the rotation of the valve body 12 progresses and the valve hole 12f1 (12f2) connects with the outlet 11b1 (outlet 11b2), the coolant flowing in from the engine side is guided from the valve hole 12f1 (valve hole 12f2) to the outlet 11b1 (outlet 11b2) at the desired flow rate.

[0039] As described above, according to this embodiment, the groove 14C is provided at the end 14A2 of the large-diameter portion 14A of the seal member 14, where the opening 14A1 is formed, at a position that first overlaps with the valve holes 12f1 and 12f2 upon rotation of the valve disc 12. This allows the coolant to begin flowing from the groove 14C to the outlet 11b, preventing a sudden outflow of the coolant into the outlet 11b and enabling a minute flow rate to be controlled. Furthermore, since this structure does not require a minute flow rate through a narrow slit as in the conventional structure, clogging by foreign matter can be suppressed. Furthermore, while the effect of the groove 14C formed in the large-diameter portion 14A cannot be obtained when the seal member 14 rotates in the circumferential direction, the rotation-preventing engagement groove 14D provided on the outer circumferential surface of the small-diameter portion 14B can prevent the seal member 14 from rotating in the circumferential direction. Furthermore, this configuration suppresses sudden pressure fluctuations and temperature changes, improving the durability of each core component connected to the outlet 11b without increasing the number of components.

[0040] In this embodiment, an example is shown in which one groove portion 14C is provided on the opening 14A1 side of the large diameter portion 14A of the sealing member 14, but the present invention is not limited to this form, and multiple groove portions 14C may be provided along the circumferential direction of one end portion 14A2 of the sealing member 14 in which the opening 14A1 is formed.

[0041] Furthermore, in this embodiment, an example has been shown in which one engagement groove 14D is provided on the outer peripheral surface of the small diameter portion 14B of the seal member 14, but the present invention is not limited to this form, and multiple engagement grooves 14D may be provided circumferentially around the small diameter portion 14B. Furthermore, in the present invention, the engagement groove 14D as an engagement portion may not be a groove shape (concave shape) but may be a convex shape such as a rib. In this case, a concave shape such as a groove (not shown) may be provided on the inner peripheral surface of the adapter 13 into which the small diameter portion 14B is inserted so as to engage with a convex portion as an engagement portion formed on the small diameter portion 14B.

[0042] 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 valve element may have one valve portion, or three or more spherical valve portions connected in the axial 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 have a cylindrical valve element with a straight outer wall surface.

[0043] 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 appropriately 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 circumferential surface 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).

[0044] Furthermore, in this embodiment, the sealing members 14 (141, 142) are configured to be pressed against the outer wall of the valve body 12 by the biasing force of the coil springs 19 (191, 192) as shown in FIG. 1, but this is not limited to this, and other structures may be used as long as they can prevent leakage of the coolant that passes through the outlet 11b and is discharged into the adapter 13 side.

[0045] Furthermore, although the preferred embodiments of the present invention have been described in detail, modifications, variations and changes can be made without departing from the scope of the appended claims.

[0046] REFERENCE SIGNS LIST 1 Motor-operated valve 11 Housing 11a Inlet (opening) 11b Outlet (communication port) 12 Valve body 12a Shaft 12b1 First valve portion (valve body) 12b ２ Second valve section (valve body) 12f １ Valve hole 12f ２Valve hole 12m Outer wall (valve outer wall) 12n Groove portion 14 Seal member 14A Large diameter portion (first cylindrical portion) 14A1 Opening 14A2 One end portion 14B Small diameter portion (second cylindrical portion) 14C Groove portion 14D Engagement groove (engagement portion) 20 Valve body 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 circumferential surface; a valve body rotatably inserted into said housing for opening and closing said communication port; a cylindrical sealing member attached to said communication port and in sliding contact with the circumferential surface of said valve body; and a drive device for rotating said valve body, wherein said valve body has a cylindrical valve body, said valve body having an outer wall capable of closing the communication port of said housing, a valve hole capable of communicating with said communication port, and a valve opening formed in one end of said valve body and communicating with the opening of said housing, said cylindrical sealing member having one end with an opening formed therein slidingly contacting the circumferential surface of said valve body, and said one end of said sealing member having a groove portion formed therein which leads to said opening.

2. The electric valve according to claim 1, characterized in that at least the area radially outward of the groove portion at one end of the sealing member in which the opening is formed is formed to be able to slide against the peripheral surface of the valve body.

3. The electric valve as described in claim 1, characterized in that the sealing member is provided with a concave or convex engaging portion formed on the outer peripheral surface of the sealing member and engages with a convex or concave portion formed on the communication port side.

Images