Valve device

Abstract

To provide a valve device which achieves reduction of power consumption.SOLUTION: A valve device (100) of the invention includes: an inflow part (18) into which a fluid flows; a first outflow part (11) from which the fluid flowing from the inflow part (18) flows out; a first passage A connecting the inflow part (18) with the first outflow part (11) and having a first valve (70); and a second passage B which connects the inflow part (18) with the first outflow part (11), is different from the first passage A, and has a second valve (80). A first passage area S1, which is a minimum passage area in the first passage A, is formed larger than a second passage area S2, which is a minimum passage area in the second passage B. The first valve (70) is a thermostat, and the second valve is a motor valve.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a valve device for adjusting the flow rate of cooling water for cooling a device. [Background technology]

[0002] Conventionally, as described in Patent Document 1, a flow control valve that adjusts the flow rate according to predetermined conditions has been used. The flow control valve has a coolant inlet and multiple outlets for sending out the inflowing coolant, and the coolant is sent to each device through pipes connected to each outlet. The above document discloses a flow control valve for automotive coolant. The flow control valve is provided in the cylinder head of the engine, and coolant is introduced into the flow control valve through an inlet passage.

[0003] The flow control valve has a motor and a valve element that is controlled to open and close by the motor via a speed reducer. Coolant is sent from the flow control valve to the heating heat exchanger, oil cooler, and radiator, and the amount of coolant sent to each of these devices is regulated by the valve element. The flow control valve is electrically controlled by an on-board electronic controller in accordance with the coolant temperature and vehicle operating conditions, etc., and the valve element is opened and closed to send the introduced coolant to the heating heat exchanger, oil cooler, and radiator. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-218763 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the conventional valve device, the motor-operated valve must be operated relatively frequently to control the cooling water to a predetermined temperature, which results in a problem of large power consumption.

[0006] The present invention has been made to solve the above problems, and has an object to provide a valve device with reduced power consumption. [Means for solving the problem]

[0007] The valve device according to the present invention comprises: an inlet portion into which the fluid flows; a first outlet portion through which the fluid flowing in from the inlet portion flows out; a first flow path connecting the inlet and the first outlet, the first flow path having a first valve; and a second flow path that connects the inlet and the first outlet, is a flow path different from the first flow path, and has a second valve. It is equipped with a first flow path area that is the smallest flow path area in the first flow path is larger than a second flow path area that is the smallest flow path area in the second flow path, The first valve is a thermostat, The second valve is an electrically operated valve.

[0008] According to the present invention, the first flow path is larger than the second flow path and is formed as a flow path with a sufficient flow area as a main flow path, and the first valve in the first flow path is a thermostat that opens and closes by the operation of a temperature-sensing part that expands and contracts in response to changes in the temperature of the fluid. Therefore, the valve device according to the present invention can adjust temperature by mainly operating the thermostat, which does not consume electricity, and can reduce power consumption compared to conventional products that mainly operate a motor-operated valve.

[0009] Furthermore, the valve device according to the present invention has an electrically operated valve in the second flow path, so that the second valve can be opened quickly when necessary.

[0010] In addition, in the valve device according to the present invention, the second valve may be configured to connect the inflow port and the first outflow port when the fluid temperature becomes higher than the valve opening temperature of the first valve by a predetermined amount. In this way, if the fluid temperature becomes high even though the first valve, which is a thermostat, is open, the flow rate of the fluid flowing through the radiator can be increased to quickly reduce the fluid temperature.

[0011] The valve device according to the present invention further comprises: a second outlet through which the fluid flowing in from the inlet flows out; a third flow path connecting the inlet portion and the second outlet portion; It is equipped with The second valve is not only the flow rate of the fluid in the second flow path but also the flow of the fluid from the third flow path to the second outlet portion, the second flow path is controlled to either a fully closed state in which the flow of fluid to the first outlet portion via the second flow path is prevented, or a fully open state in which the flow of fluid to the first outlet portion via the second flow path is at a maximum flow rate, The third flow path may be controlled to either a fully closed state, which prevents the flow of fluid to the second outlet port via the third flow path, or a fully open state, which allows the flow of fluid to the second outlet port via the third flow path to be at a maximum flow rate.

[0012] According to the above configuration, when the second valve connects the second flow path and the third flow path, the opening degree of each flow path is not adjusted in multiple steps or continuously, so that the power required for opening and closing the second valve and for continuously monitoring the fluid temperature can be reduced. Therefore, the valve device according to the present invention can be a valve device with reduced power consumption. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic diagram of a cooling system including a valve device according to an embodiment of the present invention; [Figure 2] 2 is a longitudinal cross-sectional view of the valve device of the present embodiment, taken along line II-II in FIG. 3. FIG. [Figure 3] FIG. 2 is a bottom view of the valve device of the present embodiment. [Figure 4] 2 is a vertical cross-sectional view showing a state in which a first valve and a second valve are open in the valve device of the present embodiment. FIG. [Figure 5] FIG. 5 is an enlarged view of part C in FIG. [Figure 6] 6 is a cross-sectional view taken along the line VI-VI in FIG. 4. DETAILED DESCRIPTION OF THE INVENTION

[0014] <Embodiment> A valve device 100 according to an embodiment of the present invention will be described with reference to Figures 1 to 3. Figure 1 is a schematic diagram of a cooling system including the valve device 100 according to this embodiment. Figure 2 is a vertical cross-sectional view of the valve device 100. Figure 3 is a bottom view of the valve device 100.

[0015] Referring to FIG. 1, an automotive cooling system to which a valve device 100 is applied will be described. The valve device 100 can be used as a flow control valve in a cooling system, and can be used, for example, in an automotive cooling system. The valve device 100 used in an automotive cooling system is attached, for example, to a cylinder head CH of an internal combustion engine ENG mounted on a vehicle. Cooling system fluid, i.e., coolant, pressurized by a water pump WP mounted on the internal combustion engine ENG is introduced into the valve device 100. The valve device 100 adjusts and distributes the coolant to a radiator RAD and a coolant utilization device. The valve device 100 has a first valve and a second valve, each of which adjusts the flow rate of the coolant delivered from the valve device 100. The first valve is a thermostat 70, and the second valve is an electric valve 80.

[0016] The valve device 100 includes a housing 10, a thermostat 70 housed in the housing 10, and an electric valve 80. The electric valve 80 includes a second valve body 81, a motor 65, and a reduction gear 66. The valve device 100 has two flow paths for flowing coolant to the radiator RAD. One of the flow paths is a first flow path A, which is equipped with a thermostat 70. The other flow path is a second flow path B, which is equipped with an electric valve 80 whose opening and closing is controlled by a control device (not shown).

[0017] The cooling water introduced into the valve device 100 is sent to a radiator RAD, which is a heat radiator, and to a plurality of cooling water utilization devices. In this embodiment, the cooling water utilization devices are a heater HT and a transmission TM such as an AT or CVT. The cooling water utilization devices are not limited to the heater HT and the transmission TM, and may be, for example, an oil cooler, an exhaust gas recirculation device, etc. In this way, the vehicle is provided with necessary devices as cooling water utilization devices.

[0018] A pipe L1 is connected between the valve device 100 and the radiator RAD. The cooling water to the radiator RAD is sent from the valve device 100 through the feed-side pipe L1. The radiator RAD is equipped with a blower fan FAN that blows air to the radiator RAD to dissipate heat. The cooling water dissipates heat as it passes through the radiator RAD, lowering its temperature. The cooling water that has passed through the radiator RAD is returned to the internal combustion engine ENG through the return-side pipe L1.

[0019] The cooling water is sent from the valve device 100 to the heater HT and the transmission through feed-side pipes L2 and L3, respectively. After passing through each cooling water utilization device, the cooling water is returned to the internal combustion engine ENG through return-side pipes L2 and L3. The cooling water returned to the internal combustion engine ENG is pressurized by the water pump WP and sent out again, circulating between the radiator RAD and each cooling water utilization device.

[0020] The configuration of the valve device 100 will be described with reference to Figures 2 and 3. The valve device 100 includes a housing 10 that forms the main body of the valve device 100, a motor 65, a reduction gear 66, a thermostat 70, and an electric valve 80, which are all housed in the housing 10.

[0021] The housing 10 will be described with reference to Figures 2 and 3. The housing 10 includes a first outlet 11 through which coolant is delivered to the radiator RAD, a second outlet 12 and a third outlet 13 through which coolant is delivered to each coolant utilization device, and an inlet 18 through which coolant is introduced from the internal combustion engine ENG. The housing 10 further includes a valve housing 20, a motor housing 26, and a reduction gear housing 27. The valve device 100 is fixed with the lower surface of the valve housing 20 abutting against the cylinder head CH.

[0022] The housing 10 is integrally formed from a resin material. By forming the housing 10 from a resin material, the valve device 100 can be formed lighter. This reduces the fuel consumption of the vehicle to which the valve device 100 is attached. The valve accommodating portion 20, the motor accommodating portion 26, and the reduction gear accommodating portion 27 may be formed individually or individually and then assembled. Alternatively, one or more of the valve accommodating portion 20, the motor accommodating portion 26, and the reduction gear accommodating portion 27 may be formed from a material other than a resin material, such as a lightweight metal material, for example, an aluminum alloy.

[0023] 2 and 3, the first outlet 11, the second outlet 12, and the third outlet 13, which are cooling water outlets, will be described. A first adapter 23 to a third adapter 25 are fitted and fixed into the first outlet 11 to the third outlet 13, respectively. The first adapter 23 to the third adapter 25 are members having hollow cylindrical portions to which one of the pipes L1 to L3 is connected. One end 31 of the first adapter 23 is inserted into a first opening 14 of the first outlet 11. One end 32 of the second adapter 24 is inserted into a second opening 15 of the second outlet 12. The third adapter 25 is inserted into a third opening (not shown) of the third outlet 13.

[0024] A pipe L1 (not shown) that delivers cooling water to the radiator RAD is connected to the open end of the first adapter 23. A pipe L2 that delivers cooling water to the heater HT is connected to the open end of the second adapter 24. A pipe L3 that delivers cooling water to the transmission TM is connected to the open end of the third adapter 25. The cooling water utilization devices connected to the second adapter 24 and the third adapter 25 are appropriately selected depending on the vehicle in which the valve device 100 is installed, and may be, for example, an oil cooler or an exhaust gas recirculation device. Furthermore, the second adapter 24 and the third adapter 25 may each be connected to two or more cooling water utilization devices via bifurcated pipes that branch the flow path, rather than just one.

[0025] One end 31 of the first adapter 23, one end 32 of the second adapter 24, and one end (not shown) of the third adapter 25 each have a sealing device including a seal and a spring. The first adapter 23 has a seal 33 and a spring 76 provided at its one end 31. The second adapter 24 has a seal 37 and a spring 77 provided at its one end 32. The seal 33 is formed in a generally cylindrical shape, with a thin elastic membrane connecting an annular portion 34 with a generally circular cross section provided at one end of the seal 33 and an annular portion 35 with a generally circular cross section provided at the other end. Similarly, the seal 37 is formed in a generally cylindrical shape, with a thin elastic membrane connecting an annular portion 38 with a generally circular cross section provided at one end of the seal 37 and an annular portion 39 with a generally circular cross section provided at the other end.

[0026] The diameters of the annular portions 34 and 38 provided at one end of the seals 33 and 37 are smaller than the diameters of the annular portions 35 and 39 provided at the other end of the seals 33 and 37. Therefore, the seals 33 and 37 are formed in a cylindrical shape with a diameter that gradually increases from one end to the other. The seals 33 and 35 are integrally formed from an elastic material, such as a resin material or rubber.

[0027] The first and second adapters 23 and 24 have cylindrical ends 31 and 32 with openings, and annular portions 35 and 39 at the other ends of the seals 33 and 37 are attached to the outer peripheral surfaces of the first and second adapters 23 and 32 by interference fit. Springs 76 and 77, each with an outer diameter slightly smaller than the inner diameter of the end 31 and 32, are inserted into the openings of the end 31 and 32. One end of each spring 76 and 77 protrudes outside the end 31 and 32, while the other end of each spring 76 and 77 is inserted into the opening of the end 31 and 32. An annular surface is formed on the inner surface of the opening of the end 31 and 32, perpendicular to the central axes X1 and X2 of the end 31 and 32. The ends of the springs 76 and 77 inserted into the end 31 and 32 are attached in contact with the annular surface.

[0028] The annular portions 34, 38 at one end of the seals 33, 37 are in contact with corresponding portions of the motor-operated valve 80. The annular portions 34, 38 at one end of the seals 33, 37 have annular surfaces perpendicular to the central axes X1, X2 on the surfaces of the other ends of the seals 33, 37. One end of each of the springs 76, 77 is attached to each of the annular surfaces. That is, the annular portions 34, 38 at one end of the seals 33, 37 are pressed against the corresponding curved surfaces of the motor-operated valve 80 by the springs 76, 77. Therefore, even when the motor-operated valve 80 is operated and rotated, the seals 33, 37 follow and maintain contact, and the cooling water flowing out of the motor-operated valve 80 can flow through the first adapter 23 and the second adapter 24 without leaking due to the seals 33, 37. In addition, one end of the third adapter 25 also has a sealing device including a seal and a spring of a similar shape to one end 31 of the first adapter 23 and one end 32 of the second adapter 24, and is configured in the same or similar structure.

[0029] With reference to Figure 2, the abutment portion 17 provided at the bottom of the valve accommodating portion 20 will be described. An open cylinder head opening OP is provided in the cylinder head CH of the internal combustion engine ENG. The abutment portion 17 has a flat surface so that it can abut against the mounting portion of the cylinder head CH in the housing 10. The abutment portion 17 is provided with an inlet portion 18 that corresponds to the opening shape of the cylinder head opening OP. The valve device 100 abuts against the mounting surface of the cylinder head CH with the inlet portion 18 aligned with the cylinder head opening OP and is fixed to the cylinder head CH with bolts (not shown). The inlet portion 18 is an opening provided in the abutment portion 17.

[0030] The contact portion 17 has a seal 19 provided to surround the outside of the inlet portion 18 at the contact portion 17. Cooling water pressurized by the water pump WP is sealed by the seal 19 and introduced into the inlet portion 18 from a cylinder head opening OP of the internal combustion engine ENG without leaking.

[0031] The valve housing portion 20 communicates with the inlet portion 18. The internal space has a first space 21 and a second space 22, each formed in a substantially cylindrical shape. The first space 21 and the second space 22 are disposed close to each other so that their outer peripheries partially overlap, and the two spaces communicate with each other. A thermostat 70 is accommodated in the first space 21, and an electric valve 80 is accommodated in the second space 22. As shown in FIG. 2 , the valve housing portion 20 has a first outlet portion 11 located above the first space 21. A valve seat 29 formed integrally with the valve housing portion 20 is provided between the first space 21 and the internal space within the first outlet portion 11. The valve seat 29 is formed in an annular shape so that the thermostat 70 can abut against it.

[0032] As shown in FIG. 3, the motor 65 is accommodated in a motor housing 26, which has an internal sealed space and is provided on the side of the valve housing 20. Also, as shown in FIG. 2, the reduction gear 66 is accommodated in a reduction gear housing 27 formed on the upper part of the valve device 100. The reduction gear housing 27 has an enclosed space sealed by a cover 28 that forms the upper part of the housing 10. The reduction gear 66 has multiple gears 67, and the driving force of the motor 65 is transmitted in order from a first gear 67 fixed to an output shaft (not shown) of the motor 65 to a final gear 67, thereby forming a multi-stage reduction mechanism. The multiple gears 67 are formed as spur gears with different diameters and numbers of teeth, and are rotatably supported by parallel rotating shafts (not shown). Note that the reduction mechanism is not limited to gears, and may be other devices. For example, the reduction mechanism may be formed using a pulley and a belt.

[0033] A rotary shaft 87 of the motor-operated valve 80 is fitted into a fitting hole provided in the center of the final-stage gear 67. A gear on the output shaft (not shown) of the motor 65 meshes with the first-stage gear 67, and the rotation of the motor 65 is controlled by a control device, and the rotational torque is transmitted by a reduction gear 66. The rotational force transmitted to the final-stage gear 67 rotates the motor-operated valve 80 by a predetermined rotation angle in one direction or the other direction.

[0034] The reduction gear 66 can be configured in other ways as well. The shape, size, number of teeth, orientation of the rotation axis of the multiple gears 67 that make up the reduction gear 66, and arrangement within the reduction gear accommodating section 27 are determined appropriately depending on the required output torque, the size of the reduction gear accommodating section 27, etc.

[0035] As shown in FIG. 3 , a support member 40 is fitted into the inlet portion 18. The support member 40 is a member that supports the lower end of the rotary shaft 87. The support member 40 has multiple rod-shaped members 41 and a central portion 43 whose central axes are coaxial with the rotary shaft 87. In a plan view, the support member 40 is formed such that the rod-shaped members 41 protrude radially from the central portion 43. The three rod-shaped members 41 are arranged at 120-degree intervals around the center of the central portion 43, forming a substantially Y-shape. The ends of each rod-shaped member 41 are fixed to the inner wall of the inlet portion 18. Because the rod-shaped members 41 are arranged in a space through which cooling water flows, each rod-shaped member 41 is formed thin while maintaining the necessary strength. The number of rod-shaped members 41 may be other than three. For example, a total of two rod-shaped members 41 may be arranged at 180-degree intervals around the center of the central portion 43, forming the support member 40 in an I-shape. Alternatively, a total of four rod-shaped portions 41 may be provided around the center of the central portion 43 at 90-degree intervals, so that the support portion 40 is formed in a cross shape.

[0036] [Configuration of the motor-operated valve 80] The configuration of the motor-operated valve 80, which is the second valve, will be described with reference to Figure 2. The motor-operated valve 80 is an on-off valve that opens and closes when a second valve body 81 rotates using the driving force of a motor 65 transmitted via a reduction gear 66. The second valve body 81 is housed in the second space 22, which is the internal space of the valve housing portion 20. The second valve body 81 is formed in a generally cylindrical shape with an internal space, and has a central cylindrical portion 82 with a central hole 82a, and a rotary shaft 87 that fits into the central cylindrical portion 82.

[0037] The cylindrical second valve body 81 has a first cylindrical portion 83 and a second cylindrical portion 84, each of whose outer circumferential surfaces protrude in an arcuate shape in side view. The first cylindrical portion 83 and the second cylindrical portion 84 are stacked vertically along the central axis X3 of the motor-operated valve 80. The first cylindrical portion 83 and the second cylindrical portion 84 are formed so as not to rotate relative to each other. The first cylindrical portion 83 and the second cylindrical portion 84 are connected to the central cylindrical portion 82 via multiple bridge portions (not shown). The area between the first cylindrical portion 83, the second cylindrical portion 84, and the central cylindrical portion 82, except for the bridge portions (not shown), forms a flow path for cooling water. The upper first cylindrical portion 83 of the motor-operated valve 80 is located on a longitudinal extension of the first adapter 23. The lower second cylindrical portion 84 of the motor-operated valve 80 is located on a longitudinal extension of the second adapter 24. The outer circumferential surfaces of the first cylindrical portion 83 and the second cylindrical portion 84 are each provided with a valve opening 85, 86 that communicates with the internal space of the motor-operated valve 80. The valve openings 85, 86 are formed as elongated holes that are parallel to a plane perpendicular to the central axis X3, and open within a predetermined angular range on the outer circumferential surface of the motor-operated valve 80 when viewed from above, centered on the central axis X3.

[0038] The first cylindrical portion 83 and the second cylindrical portion 84 are configured to rotate integrally by the driving force of the central shaft 87 of the reduction gear 66. Meanwhile, the temperature range of the coolant delivered to the radiator RAD connected to the valve device 100 and each coolant utilization device differs depending on the coolant utilization device. Therefore, the opening angles of the elongated holes of the valve opening 85 and the valve opening 86 and the opening positions on the outer circumferential surfaces of the first cylindrical portion 83 and the second cylindrical portion 84 are determined so that the valve opening state is optimized for each radiator RAD and each coolant utilization device. The elongated holes of the valve openings 85, 86 are each formed at an opening angle of 180 degrees or less when viewed from above, centered on the central axis X3.

[0039] When the second valve body 81 rotates and the valve opening 85 overlaps the opening of the annular portion 34 of the seal 33 provided on the first adapter 23, the pipe L1 opens and the coolant circulates through the radiator RAD. When the valve opening 86 overlaps the annular portion 38 of the seal 37 provided on the second adapter 24, the pipe L2 opens and the coolant circulates through the heater HT. When the valve opening 86 overlaps the annular portion of a seal (not shown) provided on the third adapter 25, the pipe L3 opens and the coolant circulates through the transmission TM. In this way, the motor-operated valve 80 opens and closes the pipes L1 to L3 by rotating the second valve body 81.

[0040] In the valve device 100 of the embodiment, the thermostat 70 is disposed in the first flow path A as the normally used main flow path, and the motor-operated valve 80 is disposed in the second flow path B as the sub-flow path. Therefore, the thermostat 70 as the first valve of the normally used main flow path does not require power, and can open the motor-operated valve 80 in response to temperature changes in the coolant when necessary. Therefore, the valve device 100 of the embodiment can be a valve device 100 with reduced power consumption.

[0041] Furthermore, in the valve device 100 of the embodiment, the motor-operated valve 80 as the second valve is not used as the main valve, so it only needs to be opened and closed when necessary. This makes it possible to reduce the power required for opening and closing the motor-operated valve 80 (second valve) and for continuously monitoring the fluid temperature Tx. Furthermore, because the number of opening and closing operations of the motor-operated valve 80 is reduced, wear on the seals 33 and 37 in contact with the motor-operated valve 80 is reduced, thereby extending the service life of the valve device 100. Furthermore, the control program for the motor-operated valve 80 can be configured more simply. Therefore, the valve device 100 according to the present invention can be a valve device 100 with reduced power consumption.

[0042] [Thermostat 70 Configuration] The configuration of the thermostat 70, which is the first valve, will be described with reference to Figure 2. The thermostat 70 is an on-off valve that operates by utilizing the properties of wax, which expands and contracts depending on the temperature of the coolant. The thermostat 70 is housed in the first space 21.

[0043] The thermostat 70 has a rod 71, a wax housing 72 housing wax that expands and contracts in response to changes in the coolant temperature, a valve element 73, a spring 74, and a spring retaining plate 75. The upper end of the rod 71 is inserted into a blind hole provided on the inner surface of the upper part of the valve housing 20, and is attached in the vertical direction. The lower end of the rod 71 is housed in the wax housing 72. The rod 71 moves in the vertical direction relative to the wax housing 72 due to the expansion and contraction of the wax. A substantially circular valve element 73 is fixed to the outer periphery of the upper end of the wax housing 72 so as not to move relative to the wax housing 72. A spring retaining plate 75 is supported by the valve housing 20 at the lower end of the thermostat 70. A spring 74 is held between the valve element 73 and the spring retaining plate 75.

[0044] The operation of the thermostat 70, which is the first valve, will be described with reference to FIG. 4. FIG. 4 shows the thermostat 70 in FIG. 2 in an open state. The thermostat 70 operates when the wax filled in the wax storage section 72 expands or contracts due to temperature changes. When the coolant temperature Tx around the wax storage section 72 reaches or exceeds the first temperature T1, the wax in the wax storage section 72 gradually expands in accordance with the coolant temperature Tx. As a result, the wax storage section 72 moves downward. Therefore, the valve element 73 fixed to the wax storage section 72 moves downward together with the wax storage section 72. As a result, the valve element 73 separates from the valve seat 29, and the valve of the thermostat 70 opens.

[0045] The thermostat 70 gradually opens in response to the coolant temperature Tx above the first temperature T1, and is fully open at a predetermined temperature. Therefore, the thermostat 70 increases its valve opening in response to an increase in the coolant temperature Tx, allowing the amount of coolant passing through the thermostat 70 to continuously increase. When the thermostat 70 is open, the inlet portion 18 and the first space 21 communicate with the internal space of the first outlet portion 11. The flow of coolant passing through the thermostat 70 and flowing to the radiator RAD is the first flow path A to the radiator RAD. In FIG. 4, the first flow path A is indicated by a dashed arrow A.

[0046] [Operation of the thermostat 70 and the motor-operated valve 80] The operation of the thermostat 70 and the motor-operated valve 80 in the first flow path A and the second flow path B will be described with reference to Figures 2 and 4. Figure 4 is a vertical cross-sectional view of the valve device 100, the same as Figure 2, showing the thermostat 70 and the motor-operated valve 80 in an open state. The opening of the thermostat 70 is automatically adjusted by the expansion and contraction of wax in accordance with the coolant temperature Tx. The temperature at which the thermostat 70 opens (valve opening temperature) is designated as T1.

[0047] The motor-operated valve 80 is controlled to open the pipe L1 under predetermined conditions and to open the pipes L2 and L3 according to the cooling water temperature Tx. The temperature at which the motor-operated valve 80 opens the pipe L2 is T2a, and the temperature at which the motor-operated valve 80 opens the pipe L3 is T2b. The valve opening temperature T2a of the motor-operated valve 80 for the pipe L2 and the valve opening temperature T2b of the pipe L3 are lower than the valve opening temperature T1 of the thermostat 70 (T1>T2a, T1>T2b). In this embodiment, the valve opening temperature T2a of the pipe L2 is lower than the valve opening temperature T2b of the pipe L3 (T2a <T2b)。

[0048] The predetermined conditions for the electric valve 80 to open the pipe L1 can be arbitrarily set. For example, the predetermined conditions are when the cooling water becomes higher than the valve opening temperature T1 of the thermostat 70 by a predetermined amount or more, when the accelerator is fully open and a rapid temperature rise is expected, when hunting or knocking occurs, etc. That is, the electric valve 80 opens the pipe L1 so as to assist the thermostat 70. In other words, the electric valve 80 cooperates with the thermostat 70 to control the flow rate of the cooling water passing through the radiator RAD.

[0049] (1) When Tx < T1, Tx < T2a, and Tx < T2b Before the internal combustion engine ENG starts, the cooling water temperature Tx is approximately the outside air temperature. When the internal combustion engine ENG starts, the cooling water temperature Tx gradually rises. When the cooling water temperature Tx does not reach the valve opening temperatures T1, T2a, and T2b of the pipes L2 and L3 of the thermostat 70 and the electric valve 80 (Tx < T1, T2a, T2b) and the predetermined conditions are not satisfied, both the thermostat 70 and the electric valve 80 are in the closed valve state, which is the state shown in FIG. 2.

[0050] (2) When Tx < T1, T2a ≤ Tx, and Tx < T2b When the cooling water becomes warm enough and the cooling water temperature Tx becomes equal to or higher than the valve opening temperature T2a of the pipe L2, the electric valve 80 opens the pipe L2. As a result, the warmed cooling water circulates through the heater HT.

[0051] (3) When Tx < T1, T2a ≤ Tx, and T2b ≤ Tx When the cooling water becomes even warmer and the cooling water temperature Tx becomes equal to or higher than the valve opening temperature T2b of the pipe L3, the electric valve 80 opens the pipe L3. As a result, the warmed cooling water circulates through the transmission TM. At this time, the electric valve 80 is maintained in the state where the pipe L2 is open. That is, when the cooling water temperature Tx becomes equal to or higher than the valve opening temperature T2b of the pipe L3, the electric valve 80 opens the pipes L2 and L3, and the cooling water circulates through the heater HT and the transmission TM.

[0052] (4) When T1 ≤ Tx, T2a ≤ Tx, and T2b ≤ Tx When the coolant is further heated and the coolant temperature Tx becomes equal to or higher than the valve opening temperature T1 of the thermostat 70, the thermostat 70 opens the pipe L1, and the coolant circulates through the radiator RAD.

[0053] More specifically, when the coolant temperature Tx reaches or exceeds T1, the wax in the wax storage portion 72 of the thermostat 70 expands, causing the valve element 73 to move against the spring force of the spring 74. The valve element 73 moves away from the valve seat 29, connecting the first space 21 to the internal space of the first outlet portion 11, thereby forming a first flow path A. In FIG. 4, the flow of coolant in the first flow path A is indicated by the dashed arrow A. The wax expands and contracts according to the coolant temperature Tx, automatically adjusting the opening of the thermostat 70.

[0054] (5) Under specified conditions When a predetermined condition is met, such as when the coolant temperature Tx is higher than the valve opening temperature T1 of the thermostat 70 by a predetermined amount, the motor-operated valve 80 opens the pipe L1. More specifically, when the predetermined condition is met, the output of a coolant temperature sensor (not shown) causes the control device to rotate the motor-operated valve 80 using the motor 65, thereby opening the valve opening 85. The first cylindrical portion 83 rotates until the valve opening 85 is fully open. As a result, the internal space of the motor-operated valve 80 communicates with the internal space of the first outflow portion 11, forming a second flow path B. In FIG. 4, the flow of coolant through the second flow path B is indicated by the dashed arrow B. The thermostat 70 and the valve opening 85 of the motor-operated valve 80 are both in an open state, as shown in FIG. 4.

[0055] In this way, when the coolant temperature Tx becomes higher than the valve opening temperature T1 of the thermostat 70 by a predetermined amount, the motor-operated valve 80 opens the pipe L1, and the coolant flows through the pipe L1 through both the thermostat 70 and the motor-operated valve 80. This increases the flow rate of the coolant flowing through the radiator RAD, and the coolant temperature Tx drops quickly.

[0056] The predetermined condition may also include a case where the thermostat 70 does not open for some reason, such as a malfunction, or where the thermostat 70 opens less than specified. In the above cases, the motor-operated valve 80 opens regardless of the temperature, preventing the coolant temperature Tx from exceeding the upper limit of the cooling system. In this case, the valve device 100 or a vehicle equipped with the valve device 100 is configured so that a control device can detect or estimate malfunction of the thermostat 70. For example, the valve device 100 is provided with an operating stroke sensor for the thermostat 70. Alternatively, the valve device 100, the control device that controls the valve device 100, or the vehicle equipped with the valve device 100 may be provided with a determination device that stores a coolant temperature change reference value for a predetermined time and is capable of comparing the rate of change of the coolant temperature Tx for the predetermined time with the reference value. The determination device compares the rate of change of the coolant temperature Tx for the predetermined time with the reference value to determine malfunction of the thermostat 70. Alternatively, the determination device compares the coolant temperature Tx with the operating stroke of the thermostat 70 to determine whether the thermostat 70 is malfunctioning.

[0057] In this way, the predetermined condition at which the motor-operated valve 80 opens the pipe L1 can be changed as appropriate. In addition, the temperatures T2a and T2b at which the motor-operated valve 80 opens the pipes L2 and L3 can also be changed as appropriate. Specifically, the temperature T2b at which the pipe L3 opens may be lower than the temperature T2a at which the pipe L2 opens.

[0058] [Relationship between the flow path areas of the first flow path A and the second flow path B] The relationship between the flow path area of ​​the first flow path A and the flow path B will be described with reference to Figures 5 and 6. Figure 5 is an enlarged view of part C in Figure 4. Figure 6 is a cross-sectional view taken along line IV-IV in Figure 4. When the thermostat 70 and the motor-operated valve 80 are both at their maximum opening degrees, in the valve device 100, the first flow path area S1, which is the smallest flow path area in the first flow path A, is larger than the second flow path area S2, which is the smallest flow path area in the second flow path B.

[0059] The first flow path area S1 in the first flow path A indicated by the dashed arrow A in Fig. 4 is the opening area when the valve disc 73 in the first flow path A is fully open. Fig. 5 shows a state in which the valve disc 73 is spaced a distance M from the valve seat 29 and the thermostat 70 is open. Because the valve disc 73 is formed in a substantially circular shape, the opening area, i.e., the first flow path area S1, is the area of ​​an imaginary, substantially conical surface formed by a line segment indicated by the distance M around the central axis X4. Note that even when the valve disc 73 is formed in a shape other than a circle, such as an ellipse, the first flow path area S1 corresponds to the opening area formed when the valve disc 73 is spaced from the valve seat 29 and the thermostat 70 is open.

[0060] The second flow path area S2 in the second flow path B indicated by the dashed arrow B in FIG. 4 is the minimum flow path area in the second flow path B when the first cylindrical portion 83 of the motor-operated valve 80 is fully open. FIG. 6 is a cross-sectional view taken along line IV-IV, showing the state in which the valve opening 85 has rotated toward the one end 31 of the first adapter 23. FIG. 6 is a view of the first adapter 23 viewed from inside the first cylindrical portion 83 through the valve opening 85. The shape of the valve opening 85 differs from the shape of the opening of the seal 33 attached to the one end 31. Therefore, the minimum flow path area through which the cooling water passes, i.e., the second flow path area S2, is the opening S2 where the opening of the valve opening 85 and the opening of the seal 33 attached to the one end 31 overlap when viewed from the direction shown in FIG. 6. In other words, the second flow path area S2 is the area of ​​a circle of radius R of the opening of the seal 33, excluding portions N1 and N2 hidden by the valve opening 85 when viewed from the direction shown in FIG. 6.

[0061] The valve device 100 of this embodiment includes an inflow portion 18 into which a fluid flows, a first outflow portion 11 from which the fluid that has flowed in from the inflow portion 18 flows out, a first flow path A which is a flow path connecting the inflow portion 18 and the first outflow portion 11 and has a first valve (thermostat 70), and a second flow path B which is a flow path different from the first flow path A and connects the inflow portion 18 and the first outflow portion 11 and has a second valve (motorized valve 80). A first flow path area S1 which is the flow path area of ​​the first flow path A is larger than a second flow path area S2 which is the flow path area of ​​the second flow path B. The first valve is the thermostat 70. The second valve is the motorized valve 80.

[0062] As described above, the valve device 100 has two flow paths, a first flow path A and a second flow path B, which connect the inlet portion 18 and the first outlet portion 11. A thermostat 70 is provided in the main first flow path A, which has a large flow path area, and an electric valve 80 is provided in the auxiliary second flow path B, which has a small flow path area. The thermostat 70 opens and closes according to changes in the volume of wax in response to temperature, and operates without receiving a power supply. The electric valve 80 operates by receiving a power supply.

[0063] According to the above configuration, the thermostat 70, which does not require a power supply, can function as a main valve that mainly adjusts the temperature of the coolant by controlling the flow rate of the coolant circulating through the radiator RAD. Also, the motor-operated valve 80, which requires a power supply, can function as a sub-valve that compensates for any shortage of power in the thermostat 70. Therefore, there is no need to precisely move the motor-operated valve 80 to adjust the temperature of the coolant, thereby reducing power consumption.

[0064] Furthermore, in the valve device 100 of this embodiment, when the coolant temperature Tx becomes higher than the valve opening temperature T1 of the first valve (thermostat 70) by a predetermined amount, the second valve (motorized valve 80) is set to connect the inlet portion 18 and the first flow path portion 11 (to open the pipe L1). As a result, when the coolant temperature Tx becomes high even though the thermostat 70 is open, the flow rate of the coolant flowing through the radiator RAD can be increased, thereby quickly lowering the coolant temperature Tx.

[0065] For example, the motor-operated valve 80 may be set to open the pipe L1 when the temperature is 10 degrees or more higher than the valve opening temperature T1 of the thermostat 70. The temperature at which the motor-operated valve 80 opens the pipe L1 can be changed as appropriate. Also, as described above, the condition (predetermined condition) at which the motor-operated valve 80 opens the pipe L1 is not limited to temperature.

[0066] The valve device 100 of the present invention includes a second outlet 12 through which fluid flowing in from an inlet 18 flows out, and a third flow path C connecting the inlet 18 and the second outlet 12. The second valve (motorized valve 80) controls not only the flow rate of fluid in the second flow path B but also the flow of fluid from the third flow path C to the second outlet 12. The second valve (motorized valve 80) is controlled in the second flow path B to either fully closed, which blocks the flow of fluid to the first outlet 11 via the second flow path B, or fully open, which maximizes the flow of fluid to the first outlet 11 via the second flow path B. The second valve (motorized valve 80) is controlled in the third flow path C to either fully closed, which blocks the flow of fluid to the second outlet 12 via the third flow path C, or fully open, which maximizes the flow of fluid to the second outlet 12 via the third flow path C.

[0067] According to the above configuration, when the second valve (motorized valve 80) communicates the second flow path B and the third flow path C, the opening degree of each flow path is not adjusted in multiple steps or continuously, so it is possible to reduce the power required for opening and closing the second valve (motorized valve 80) and for continuously monitoring the fluid temperature. Therefore, the valve device according to the present invention can be a valve device with reduced power consumption.

[0068] Furthermore, the valve device 100 of the present invention includes a third outlet 13 through which the fluid flowing in from the inlet 18 flows out, and a fourth flow path (not shown) connecting the inlet 18 and the third outlet 13. The second valve (motorized valve 80) also controls the flow of fluid from the fourth flow path to the third outlet 13. The second valve (motorized valve 80) is controlled in the fourth flow path only to either fully closed, which prevents the flow of fluid to the third outlet 13 via the fourth flow path, or fully open, which maximizes the flow of fluid to the third outlet via the fourth flow path. In this way, by controlling the opening degree of each flow path opened and closed by the second valve (motorized valve 80) to either fully closed or fully open, control of the motorized valve 80 is made easier and power consumption can be reduced.

[0069] The control method for the second valve (motorized valve 80) can be changed as appropriate. For example, any or all of the flow paths whose flow rates are controlled by the second valve may be controlled in multiple steps or continuously. The number of flow paths whose flow rates are controlled by the second valve can also be changed as appropriate.

[0070] <Other embodiments> In the above embodiment, the valve device according to the present invention has been described, which includes a first flow path A having a thermostat and a second flow path B having a motor-operated valve, and in which the first flow path area S1, which is the smallest flow path area of ​​the first flow path A, is larger than the second flow path area S2, which is the smallest flow path area of ​​the second flow path B. However, the valve device of the present invention is not limited to this, and may be modified as appropriate without departing from the spirit of the present invention. For example, the valve device 100 may be applied to vehicles other than those equipped with an internal combustion engine ENG as the only drive source, and may be applied to devices for vehicles or non-vehicles that are cooled by fluid, such as an internal combustion engine ENG in a hybrid vehicle or a driving force generating motor in an electric vehicle.

[0071] Although the valve opening 85 of the first cylindrical portion 83 of the motor-operated valve 80 is rotationally controlled to be in only a fully closed or fully open state, as described above, it may be controlled to a partial opening state between the fully closed and fully open states. For example, the valve opening 85 of the first cylindrical portion 83 and the valve opening 86 of the second cylindrical portion 84 may be continuously controlled to gradually open and close from the fully closed state to the fully open state. Alternatively, the valve opening 85 of the first cylindrical portion 83 and the valve opening 86 of the second cylindrical portion 84 may be controlled to the fully closed and fully open states, or in a stepwise manner between the fully closed and fully open states, such as 25%, 50%, and 75% open. This allows for precise response to changes in the coolant temperature. This method reduces power consumption compared to continuous control.

[0072] Furthermore, at least one of the valve openings 85, 86 may be a perfect circle instead of an elongated hole. The second valve may be configured with a thermostat 70 instead of the motor-operated valve 80. That is, both the first valve and the second valve may be configured with a thermostat 70. In this case, it is possible to adjust the flow rate of the cooling water while significantly reducing power consumption. Furthermore, the time and expense involved in developing a control program for the motor-operated valve is not required.

[0073] Furthermore, in the present invention, the materials of the components, the positions of the various pipes, and the arrangement of the devices in the cooling circuit, which have been explained in the above embodiment, may be changed as appropriate. [Explanation of symbols]

[0074] 10. Housing 11 First Outlet 12 Second Outlet 13 Third Outlet 18 Inlet 23 First Adapter 24 Second Adapter 25 Third Adapter 40 Support part 65 motor 66 Reducer 70 Thermostat (first valve) 73 Valve body 80 Electric valve (second valve) 83 First cylindrical part 84 Second cylindrical section 85,86 Valve opening 87 Rotational Axis A First flow path B Second flow path C Third flow path S1 First flow area S2 Second flow area T1 Opening temperature of the first valve (thermostat 70) Tx Fluid temperature (cooling water temperature)

Claims

1. an inlet portion into which the fluid flows; a first outlet portion through which the fluid flowing in from the inlet portion flows out; a first flow path connecting the inlet and the first outlet, the first flow path having a first valve; and a second flow path that connects the inlet portion and the first outlet portion, is a flow path different from the first flow path, and has a second valve; a first flow path area that is the smallest flow path area in the first flow path is larger than a second flow path area that is the smallest flow path area in the second flow path, the first valve is a thermostat; The second valve is a motor-operated valve.

2. 2. The valve device according to claim 1, wherein the second valve is set to communicate the inlet and the first outlet when the temperature of the fluid becomes higher than a valve opening temperature of the first valve by a predetermined amount.

3. a second outlet through which the fluid flowing in from the inlet flows out; a third flow path connecting the inlet portion and the second outlet portion, The second valve is not only the flow rate of the fluid in the second flow path but also the flow of the fluid from the third flow path to the second outlet portion, the second flow path is controlled to only one of a fully closed state in which the flow of fluid to the first outlet port via the second flow path is prevented and a fully open state in which the flow of fluid to the first outlet port via the second flow path is maximized, 2. The valve device according to claim 1, wherein the third flow path is controlled to either a fully closed state that prevents fluid from flowing to the second outlet port via the third flow path, or a fully open state that allows fluid to flow to the second outlet port via the third flow path at a maximum flow rate.

Images