Valve device

Abstract

A valve device (10) includes a housing (12), a flow path formation portion (14) in which at least one flow path hole (141, 142) through which fluid passes is formed, a drive portion (16) that outputs a rotational force, and a shaft (18) that rotates about a prescribed axis under the action of the rotational force. The valve device includes a rotor (20) that increases and decreases the opening of the flow path hole in conjunction with the rotation of the shaft, and a torsion spring (28) that is disposed in a manner surrounding the axis and exerts a force on the shaft in a circumferential direction around the axis of the shaft with respect to the housing. A stopper portion (125a, 125b) that abuts against the shaft when the shaft rotates to a prescribed position to limit the rotational drive range of the shaft is provided in the housing. The stopper portion is disposed inside the torsion spring.

Description

[0001] Related applications

[0002] This application is based on Japanese Patent Application No. 2021-071793, filed on April 21, 2021, the contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to valve devices. Background Technology

[0004] Currently, there are known valve devices that adjust the opening of a flow path orifice formed on a sealing disc by changing the relative positional relationship between a valve disc connected to a shaft and a sealing disc that is non-rotatably disposed in a housing (see, for example, Patent Document 1).

[0005] Prior art literature

[0006] Patent documents

[0007] Patent Document 1: International Publication No. 2014-72379 Summary of the Invention

[0008] In the flow control valve of Patent Document 1, when the shaft and the valve disc, which is a rotor, rotate under the action of the drive unit, the opening of the flow path hole through which the fluid from the inlet of the housing toward the outlet is increased or decreased.

[0009] However, the flow control valve in Patent Document 1 does not employ any countermeasures to suppress circumferential loosening between the shaft and rotor, thus causing a deviation in the opening degree of the flow path orifice. This deviation in the flow path orifice opening becomes the primary cause of deviations in the flow rate of the fluid passing through the valve assembly, and therefore, such deviations are undesirable. This was discovered through careful investigation by the inventors.

[0010] The purpose of this disclosure is to provide a valve device capable of suppressing the opening deviation of the flow path orifice to properly adjust the flow rate of fluid through the valve device.

[0011] According to one point of view in this disclosure

[0012] The valve device includes:

[0013] The shell, which forms a fluid passage for fluid flow inside;

[0014] A flow path forming part, which is fixed to the inside of the housing, has at least one flow path hole for fluid to pass through;

[0015] The drive unit outputs rotational force;

[0016] A shaft that rotates around a predetermined axis under the action of a rotational force;

[0017] The rotor, which, along with the rotation of the shaft, increases or decreases the opening of the flow path orifice; and

[0018] A torsion spring, which is arranged to surround a shaft, applies a force to the shaft in the circumferential direction relative to the housing.

[0019] The housing is provided with a limiting part that abuts against the shaft when the shaft rotates to a predetermined position to limit the rotational drive range of the shaft.

[0020] The limiting part is located inside the torsion spring.

[0021] Therefore, if a torsion spring is used to apply force to the shaft in the circumferential direction relative to the housing, circumferential looseness between the drive unit and the shaft can be suppressed. Furthermore, if the limiting part is set inside the torsion spring, when the shaft contacts the limiting part, accidental deflection of the housing and shaft can be suppressed, and deviation of the flow path opening caused by deflection can also be suppressed.

[0022] Therefore, it is possible to suppress the opening deviation of the flow path orifice to properly adjust the flow rate of the fluid passing through the valve device.

[0023] In addition, the parenthesized reference symbols used to annotate each constituent element, etc., indicate an example of the correspondence between that constituent element, etc., and the specific constituent elements, etc., described in the embodiments described later. Attached Figure Description

[0024] Figure 1 This is a front view of the valve device according to the first embodiment.

[0025] Figure 2 From Figure 1 The arrow in section II is shown in the bottom view of the valve assembly.

[0026] Figure 3 yes Figure 1 Section III-III.

[0027] Figure 4 This is a three-dimensional view of the main body cover when viewed from the other side of the axis.

[0028] Figure 5 This is a bottom view of the main body cover.

[0029] Figure 6 This is a bottom view of the fixed plate.

[0030] Figure 7 It is a top view of the assembly of the shaft, rotor, and rod.

[0031] Figure 8 From Figure 7A three-dimensional view of the assembly of the shaft, rotor, and rod, observed in the direction of the arrow shown in VIII.

[0032] Figure 9 From Figure 7 The three-dimensional view of the assembly of the shaft, rotor, and rod is observed in the direction of the arrow shown in IX.

[0033] Figure 10 yes Figure 7 X-X sectional view.

[0034] Figure 11 This is a top view of the rotor.

[0035] Figure 12 This is a top view of the drive disk.

[0036] Figure 13 It is a top view showing the state where the drive disk is superimposed on the fixed disk.

[0037] Figure 14 This is a side view of an assembly with shafts and other components assembled on the main body cover.

[0038] Figure 15 From Figure 14 The arrow XV indicates the direction of the view of the assembly with shafts and other components assembled on the main body cover.

[0039] Figure 16 This is an explanatory diagram used to illustrate the reference position, force application range, and non-force application range of the first torsion spring.

[0040] Figure 17 Show Figure 14 Section XVII-XVII is a diagram showing the state of the shaft in its initial rotational position.

[0041] Figure 18 Show Figure 14 Section XVII-XVII is a diagram showing the state of the shaft at its maximum rotational position.

[0042] Figure 19 This is an explanatory diagram used to illustrate the positional relationship between the first torsion spring and the spring guide.

[0043] Figure 20 This is an explanatory diagram used to illustrate the positional relationship between the spring guide and the hook locking part.

[0044] Figure 21 yes Figure 3 XXI-XXI sectional view.

[0045] Figure 22 This is a block diagram of the motor control section of the valve assembly.

[0046] Figure 23 This is a flowchart illustrating the initialization process performed by the motor control unit.

[0047] Figure 24 This is an explanatory diagram illustrating the spring guide used in the valve device of the second embodiment.

[0048] Figure 25 This is an explanatory diagram used to illustrate a first modified example of the spring guide.

[0049] Figure 26 This is an explanatory diagram illustrating a second modified example of the spring guide. Detailed Implementation

[0050] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Furthermore, in the following embodiments, parts that are the same or equivalent to those described in previous embodiments will be labeled with the same reference numerals, and their descriptions may sometimes be omitted. Additionally, in embodiments where only a portion of the constituent elements is described, the constituent elements described in previous embodiments can be applied to other portions of the constituent elements. The following embodiments can be partially combined with each other as long as they fall within a range where there are no particular obstacles to combination, even without explicit indication.

[0051] (First Implementation)

[0052] based on Figures 1 to 23 The first embodiment of this disclosure will be described. In this embodiment, an example of applying the valve device 10 of this disclosure to a temperature regulating device for both cabin air conditioning and battery temperature regulation in an electric vehicle will be described. The valve device 10 used in a temperature regulating device for an electric vehicle requires fine adjustments to the temperatures corresponding to the cabin and the battery, respectively. Compared to the case in the case of a cooling water circuit for an internal combustion engine, the flow rate of the fluid needs to be adjusted with high precision.

[0053] Figure 1 The valve device 10 shown is suitable for circulating a fluid circulation loop for a fluid (cooling water in this example) used to regulate the temperature of the vehicle interior and battery. The valve device 10 can increase or decrease the flow rate of the fluid in the circulation loop via the flow path of the valve device 10, and can also cut off the flow of the fluid in that flow path. For example, LLC, including ethylene glycol, can be used as the fluid. LLC is an abbreviation for Long Life Coolant.

[0054] like Figure 1 , Figure 2As shown, the valve device 10 has a housing 12 that forms a fluid passage for fluid flow inside. The valve device 10 is composed of a three-way valve having an inlet 12a for fluid inflow, a first outlet 12b for fluid outflow, and a second outlet 12c for fluid outflow on the housing 12. The valve device 10 not only functions as a simple flow path switching valve, but also functions as a flow regulating valve to adjust the flow rate ratio of the fluid flowing from the inlet 12a to the first outlet 12b and the fluid flowing from the inlet 12a to the second outlet 12c.

[0055] The valve device 10 is configured as a disc valve in which the valve opening and closing action is performed by rotating a disc-shaped valve core around the axis CL of the shaft 18 (described later). Furthermore, in this embodiment, the direction along the axis CL of the shaft 18 (described later) is defined as the axial direction DRa, and the direction orthogonal to this axial direction DRa and extending radially from the axis CL is defined as the radial direction DRa. Additionally, in this embodiment, the direction around the axis CL is defined as the circumferential direction DRc, and various structures are described accordingly.

[0056] like Figure 3 As shown, the valve device 10 houses a fixed plate 14, a shaft 18, a rotor 20, a compression spring 26, a first torsion spring 28, a second torsion spring 30, etc., inside the housing 12. Additionally, the valve device 10 has a drive unit 16, etc., arranged on the outside of the housing 12.

[0057] The housing 12 is a non-rotating component that does not rotate. The housing 12 is formed, for example, from a resin material. The housing 12 has: a main body portion 120 with a bottom cylindrical shape extending along the axial direction DRa; and a main body cover portion 124 that closes the opening 120a of the main body portion 120.

[0058] The main body 120 has a bottom wall portion 121 forming a bottom surface and a side wall portion 122 surrounding an axis CL. The bottom wall portion 121 and the side wall portion 122 are integrally formed into a single molded part.

[0059] The bottom wall portion 121 is provided with a height difference to match the flow path holes 141, 142 of the fixing plate 14 (described later). That is, the portion of the bottom wall portion 121 that faces the flow path holes 141, 142 of the fixing plate 14 (described later) has a larger distance from the main body cover portion 124 compared to the portion that does not face the flow path holes 141, 142 of the fixing plate 14.

[0060] The bottom wall portion 121 has opposing portions 121a that are opposite to the flow holes 141, 142 of the fixed disk 14, and non-opposing portions 121b that are not opposite to the flow holes 141, 142 of the fixed disk 14. In the bottom wall portion 121, the opposing portions 121a are significantly away from the fixed disk 14, and the non-opposing portions 121b are close to the fixed disk 14.

[0061] On the side wall portion 122, an inlet portion 12a is formed at a position closer to the opening portion 120a than to the bottom wall portion 121, and a first outlet portion 12b and a second outlet portion 12c are formed at positions closer to the bottom wall portion 121 than to the opening portion 120a. The inlet portion 12a, the first outlet portion 12b, and the second outlet portion 12c are composed of tubular members with flow paths formed on their inner sides.

[0062] On the inner side of the side wall portion 122, between the portion where the inlet portion 12a is formed and the portions where the outlet portions 12b and 12c are formed, a mounting portion 122a for mounting the fixing plate 14 is provided. The mounting portion 122a is a portion that abuts against the back side of the opening surface 140 in the fixing plate 14. The mounting portion 122a is formed in the side wall portion 122 at a portion where the inner diameter changes. Specifically, the mounting portion 122a is a flat portion that extends radially DRr. A receiving groove 122b for accommodating the washer 15, which will be described later, is formed in the mounting portion 122a.

[0063] In addition, the side wall portion 122 has a first disk opposing portion 122c that is opposite to the fixed disk 14 in the radial direction DRr and a second disk opposing portion 122d that is opposite to the drive disk 22 in the radial direction DRr.

[0064] Although not shown in the diagram, a storage feature is formed on the first tray-opposing portion 122c. Figure 6 The fixed disk 14 shown has a receiving groove for the anti-rotation protrusion 144. Alternatively, the anti-rotation of the fixed disk 14 can also be achieved by, for example, an anti-rotation pin, instead of the anti-rotation protrusion 144.

[0065] The inner diameter Dh of the first disc opposing portion 122c is larger than the outer diameter Dd of the portion of the fixed disc 14 excluding the anti-rotation protrusion 144. Therefore, when the fixed disc 14 is positioned on the mounting portion 122a, a gap is formed between the fixed disc 14 and the side wall portion 122. In other words, the fixed disc 14 is not positioned by the side wall portion 122.

[0066] The inner diameter of the second disc opposing portion 122d is larger than the inner diameter of the first disc opposing portion 122c. Furthermore, the inner diameter of the second disc opposing portion 122d is larger than the outer diameter of the drive disc 22. This creates a gap between the drive disc 22 and the side wall portion 122. That is, the drive disc 22 does not contact the side wall portion 122 and is not positioned by the side wall portion 122. Additionally, the outer diameter of the drive disc 22 is approximately equal to the outer diameter Dd of the fixed disc 14.

[0067] The inner side of the housing 12 is divided into an inlet space 12d and an outlet space 12e by a fixed plate 14. The inlet space 12d is the space inside the housing 12 that communicates with the inlet portion 12a. The outlet space 12e is the space inside the housing 12 that communicates with the first outlet portion 12b and the second outlet portion 12c.

[0068] Although not shown in the figure, a plate-shaped partition is provided on the inner side of the main body 120 to divide the outlet side space 12e into a first outlet side space communicating with the first flow path hole 141 and a second outlet side space communicating with the second flow path hole 142. The partition is provided in such a way that it traverses the outlet side space 12e along the radial direction DRr.

[0069] The main body cover 124 is a cover member that covers the opening 120a of the main body 120. The main body cover 124 is composed of a plate portion 124a, a rib portion 124b, a boss portion 124c, and a spring guide portion 125. The plate portion 124a, the rib portion 124b, the boss portion 124c, and the spring guide portion 125 are integrally formed into a single molded part.

[0070] Plate portion 124a is an annular portion extending radially along DRr. Plate portion 124a, together with side wall portion 122 and fixing plate 14, forms entrance side space 12d in main body cover portion 124.

[0071] Rib 124b is the portion of the main body cover 124 that is embedded in the opening 120a of the main body 120. Rib 124b is formed in a cylindrical shape and is provided on the outer periphery of the plate portion 124a. Rib 124b is provided in such a way that it protrudes from the plate portion 124a toward the bottom wall portion 121. An O-ring 124d is disposed between rib 124b and side wall portion 122 to seal the gap between the main body portion 120 and the main body cover 124.

[0072] The boss portion 124c is the part through which the shaft 18 passes on the inner side. The boss portion 124c is formed in a cylindrical shape and is provided on the inner circumference of the plate portion 124a. The boss portion 124c protrudes from the plate portion 124a toward the axial direction Dra. The boss portion 124c has a shaft seal 124e on its inner side and an O-ring 124f on its outer side to seal the gap between it and the drive portion 16. The shaft seal 124e is an annular sealing member that seals the gap between it and the shaft 18. In addition, a bearing portion 124g that supports the shaft 18 for rotation is arranged on the inner side of the boss portion 124c.

[0073] The spring guide 125 is a guide member that holds the first torsion spring 28 in a proper position so that the first torsion spring 28 functions properly. The spring guide 125 is arranged inside the first torsion spring 28 in a manner that surrounds the axis CL. Specifically, the spring guide 125 is provided on the inner periphery of the plate portion 124a in the same manner as the boss portion 124c. Figure 4 As shown, the spring guide 125 protrudes from the plate portion 124a on the other side toward the axial direction DRa. (As...) Figure 5 As shown, the spring guide 125 is curved in an arc shape with the axis CL as the center.

[0074] In the spring guide 125, the end of the circumferential DRc forms a first limiting part 125a and a second limiting part 125b that limit the rotation of the shaft 18. Each limiting part 125a and 125b abuts against the shaft 18 when the shaft 18 rotates to a predetermined position to limit the rotational drive range of the shaft 18.

[0075] The first limiting part 125a is provided at one end of the circumferential DRc in the spring guide part 125 to limit the rotation of the shaft 18 in the first rotation direction R1. Specifically, the first limiting part 125a abuts against the rotation limiting part 189 of the shaft 18 when the shaft 18 rotates to the initial rotation position.

[0076] The second limiting part 125b is provided at the other end of the circumferential DRc in the spring guide part 125 to limit the rotation of the shaft 18 in the second rotation direction R2. Specifically, the second limiting part 125b abuts against the rotation limiting part 189 of the shaft 18 when the shaft 18 rotates to the maximum rotation position.

[0077] The fixed disk 14 is composed of a disc-shaped component. The fixed disk 14 is disposed inside the housing 12 with the axial direction DRa as the thickness direction. The fixed disk 14 has an opening surface 140 that serves as a surface for the drive disk 22 to slide. The opening surface 140 is a contact surface that contacts the sliding surface 220 of the drive disk 22, which will be described later.

[0078] It is desirable that the fixing disk 14 be formed of a material with a smaller coefficient of linear expansion and superior wear resistance compared to the material constituting the housing 12. The fixing disk 14 is made of a high-hardness material with a higher hardness than the housing 12. Specifically, the fixing disk 14 is made of ceramic. The fixing disk 14 is a powder-molded body obtained by forming ceramic powder into the desired shape using a stamping machine. Alternatively, the fixing disk 14 may be formed only of a material such as ceramic with a smaller coefficient of linear expansion and superior wear resistance compared to the material constituting the housing 12, where the opening surface 140 is formed.

[0079] Furthermore, the fixed plate 14 constitutes a flow path forming part that forms flow path holes 141, 142 for fluid to pass through. Therefore, in the valve device 10 of this embodiment, the fixed plate 14, which is the flow path forming part, is configured as a component that is not part of the housing 12.

[0080] like Figure 6 As shown, a first flow path hole 141 and a second flow path hole 142 for fluid passage are formed in the fixed disk 14. The first flow path hole 141 and the second flow path hole 142 are formed in the fixed disk 14 at positions away from the axis CL of the shaft 18, without overlapping with the axis CL. The first flow path hole 141 and the second flow path hole 142 are sector-shaped through holes, functioning as connecting paths that connect the inlet-side space 12d and the outlet-side space 12e. Alternatively, the first flow path hole 141 and the second flow path hole 142 can also be circular, elliptical, or other shapes.

[0081] Specifically, a first flow path 141 is provided in the fixed disk 14 at a location corresponding to the first outlet side space, communicating with the first outlet side space. Similarly, a second flow path 142 is provided in the fixed disk 14 at a location corresponding to the second outlet side space, communicating with the second outlet side space.

[0082] A mounting hole 143 is formed approximately at the center of the mounting plate 14. The mounting hole 143 is a fixed-side through hole through which the shaft 18 passes. The inner diameter of the mounting hole 143 is formed to be larger than the diameter of the shaft 18 in a manner that prevents the shaft 18 from slipping.

[0083] A washer 15 is disposed between the fixed disk 14 and the mounting portion 122a to seal the gap between the fixed disk 14 and the mounting portion 122a. The washer 15 is made of rubber. The washer 15 is received in a receiving groove 122b formed in the mounting portion 122a. The washer 15 has two or more protrusions on the sealing surface opposite to the fixed disk 14 and on the sealing surface opposite to the mounting portion 122a. Specifically, the washer 15 has two protrusions protruding toward the axial direction DRa. Such a washer 15 can be obtained, for example, by a simple method such as forming a recess in a flat sealing surface.

[0084] like Figure 3 and Figure 7As shown, shaft 18 is a rotating shaft that rotates around a predetermined axis CL under the action of the rotational force output from drive unit 16. Shaft 18 extends along the axial direction DRa. Both sides of shaft 18 in the axial direction DRa are rotatably supported on housing 12. That is, shaft 18 is a two-end support structure. Shaft 18 passes through fixed disk 14 and drive disk 22 and is rotatably supported on housing 12. Specifically, one side of shaft 18 in the axial direction DRa is supported by a bearing portion 124g provided inside the main body cover portion 124 so that it can rotate. In addition, the other side of shaft 18 in the axial direction DRa is supported by a bearing hole portion 121c formed in the bottom wall portion 121 of the main body portion 120. The bearing hole portion 121c is made of a sliding bearing. Alternatively, the bearing hole portion 121c may not be a sliding bearing, but may be made of a ball bearing or the like.

[0085] like Figure 3 , Figure 8 , Figure 9 , Figure 10 As shown, the shaft 18 includes a metal shaft core 181 and a resin support portion 182 connected to the shaft core 181. The shaft core 181 and the support portion 182 are connected to each other in a manner that allows them to rotate integrally. The shaft core 181 and the support portion 182 are integrally molded by insert molding, forming an insert-molded article.

[0086] The shaft portion 181 includes the shaft center CL of the shaft 18 and extends along the axial direction DRa. The shaft portion 181 is the part that serves as the rotation center of the rotor 20. The shaft portion 181 is constructed of a metal rod member to ensure straightness.

[0087] The support portion 182 is connected to one side of the shaft portion 181 along the axial direction DRa. The support portion 182 is formed into a bottomed cylindrical shape. The shaft portion 181 is connected to the inner side of the front end portion of the support portion 182 along the axial direction DRa. In other words, the end portion of the shaft portion 181 along the axial direction DRa is located inside the front end portion of the support portion 182. The front end portion of the support portion 182, which protrudes outward from the housing 12, is connected to the gear portion 162 of the drive portion 16.

[0088] The inner diameter of the support portion 182 increases progressively from one side of the axial direction DRa towards the other. Specifically, the support portion 182 includes a shaft connection portion 183 located on one side of the axial direction DRa, an intermediate portion 184 connected to the shaft connection portion 183, a small-diameter portion 185 connected to the intermediate portion 184, and a large-diameter portion 186 connected to the small-diameter portion 185. Furthermore, the inner diameter of the support portion 182 increases in the order of shaft connection portion 183, intermediate portion 184, small-diameter portion 185, and large-diameter portion 186.

[0089] The shaft connection portion 183 is the front end portion located on one side in the axial direction DRa. The shaft connection portion 181 is connected to the shaft connection portion 183. A shaft gear 183a that meshes with a part of the gear portion 162 is formed on the outer portion of the shaft connection portion 183 that protrudes outward from the boss portion 124c. The outer portion of the shaft connection portion 183 located inside the boss portion 124c is supported by the bearing portion 124g.

[0090] The intermediate portion 184 is located inside the boss portion 124c. The intermediate portion 184 has an inner diameter that is slightly larger than the outer diameter of the shaft portion 181. A shaft seal 124e, serving as a sealing member, is disposed on the outer side of the intermediate portion 184. The intermediate portion 184 forms an abutment portion that abuts against the shaft seal 124e, which serves as a sealing member.

[0091] The small-diameter portion 185 has a space formed on its inner side for arranging the compression spring 26, which will be described later. The small-diameter portion 185 has an inner diameter that is slightly larger than the inner diameter of the intermediate portion 184. The connecting end face 185a that connects the intermediate portion 184 and the small-diameter portion 185 becomes a contact portion for one end of the compression spring 26 to contact. The large-diameter portion 186 is connected to the outer side of the small-diameter portion 185.

[0092] The large-diameter portion 186 is located outside the radial DRr of the small-diameter portion 185. The large-diameter portion 186 has an inner diameter that is slightly larger than the inner diameter of the small-diameter portion 185. The large-diameter portion 186 has a cylindrical body 186a, a first large-diameter locking portion 186b, a second large-diameter locking portion 186c, a first flange portion 187, and a second flange portion 188.

[0093] The first large-diameter locking part 186b is a hook locking part for locking the hook part 282 of the first torsion spring 28, which will be described later. For example... Figure 9 As shown, the first large-diameter locking portion 186b is provided on the outer side of the body 186a, on one side in the axial direction DRa. The first large-diameter locking portion 186b protrudes from the body 186a toward the outer side in the radial direction DRa in such a way that it faces the hook portion 282 of the first torsion spring 28 in the circumferential direction DRc.

[0094] The second large-diameter locking part 186c is a hook locking part for locking the hook part 301 of the second torsion spring 30, which will be described later. For example... Figure 9 As shown, the second large-diameter locking portion 186c is located on the outer side of the body 186a, on the side opposite to the first large-diameter locking portion 186b in the axial direction DRa. The second large-diameter locking portion 186c protrudes from the body 186a toward the outer side of the radial direction DRa in such a way that it faces the hook portion 301 of the second torsion spring 30 in the circumferential direction DRc.

[0095] The first flange portion 187 and the second flange portion 188 are locking pieces that engage the shaft 18 with the engaging portion of the rod 24, which will be described later. The first flange portion 187 and the second flange portion 188 are located on the outer side of the body 186a, on the side opposite to the second large-diameter locking portion 186c in the axial direction DRa, such as... Figure 7 As shown, the first flange portion 187 and the second flange portion 188 have a shape that is approximately point-symmetrical to each other with respect to the axis CL of the shaft 18. The first flange portion 187 and the second flange portion 188 protrude from the body 186a toward the outer side of the radial DRr in such a way that they face the engaging portion of the rod 24 in the circumferential direction DRc.

[0096] The bracket portion 182, thus configured, bears the forces of the first torsion spring 28 and the second torsion spring 30 through its first large-diameter locking portion 186b and second large-diameter locking portion 186c. Furthermore, the bracket portion 182, having a first flange portion 187 and a second flange portion 188, allows the shaft 18 to contact the rod 24 at different locations along the circumferential DRc. That is, the contact portions of the shaft 18 with the rod 24 are located at different locations along the circumferential DRc.

[0097] Additionally, a rotation limiting portion 189 is provided in the support portion 182 to limit the rotational drive range of the shaft 18 on the circumferential DRc. The rotation limiting portion 189 is located below the contact portion that abuts against the shaft seal 124e in the middle portion 184 of the support portion 182. The rotation limiting portion 189 is composed of a protrusion that protrudes radially into the DRr. The rotational drive range of the shaft 18 on the circumferential DRc is limited by the contact between the rotation limiting portion 189 and one of the limiting portions 125a and 125b.

[0098] Here, the rotation limiting portion 189 protrudes radially into the DRR such that it coincides with each of the limiting portions 125a and 125b in the circumferential direction DRc. The rotation limiting portion 189 and each of the limiting portions 125a and 125b are similarly positioned inside the first torsion spring 28. Furthermore, the rotation limiting portion 189 abuts against each of the limiting portions 125a and 125b inside the first torsion spring 28. Accordingly, it is possible to suppress the application of force along the circumferential direction DRc to the rotation limiting portion 189 and each of the limiting portions 125a and 125b when they come into contact. Therefore, it is possible to suppress the deflection of the rotation limiting portion 189 and each of the limiting portions 125a and 125b in the circumferential direction DRc when they come into contact.

[0099] The rotor 20 rotates around the axis CL of the shaft 18 via the output of the drive unit 16. The rotation of the shaft 18, in turn, increases or decreases the opening of the flow path holes 141 and 142 of the fixed disk 14. For example... Figure 11As shown, the rotor 20 has a drive disc 22 that serves as a valve core and a rod 24 that connects the drive disc 22 to the shaft 18.

[0100] Figure 11 , Figure 12 , Figure 13 The drive disc 22 shown is a valve core that increases or decreases the opening degree of the first flow path orifice 141 and the second flow path orifice 142 in conjunction with the rotation of the shaft 18. The opening degree of the first flow path orifice 141 refers to the extent to which the first flow path orifice 141 is open, represented by fully opening 100% and fully closed 0%. Fully opening the first flow path orifice 141 means, for example, that the first flow path orifice 141 is not blocked by the drive disc 22 at all. Fully closing the first flow path orifice 141 means, for example, that the first flow path orifice 141 is completely blocked by the drive disc 22. The opening degree of the second flow path orifice 142 is the same as the opening degree of the first flow path orifice 141.

[0101] The drive disk 22 is composed of a disc-shaped component. The drive disk 22 is disposed inside the housing 12 with its axial direction DRa as its thickness direction. The drive disk 22 is disposed in the inlet-side space 12d facing the fixed disk 14 in the axial direction DRa. The drive disk 22 has a sliding surface 220 that faces the opening surface 140 of the fixed disk 14. The sliding surface 220 is a sealing surface that seals the opening surface 140 of the fixed disk 14.

[0102] It is desirable that the drive disk 22 be formed of a material with a smaller coefficient of linear expansion and superior wear resistance compared to the material constituting the housing 12. The drive disk 22 is made of a high-hardness material with a higher hardness than the housing 12. Specifically, the drive disk 22 is made of ceramic. The drive disk 22 is a powder-molded body obtained by forming ceramic powder into the desired shape using a stamping machine. Alternatively, the drive disk 22 may be formed only of a material such as ceramic with a smaller coefficient of linear expansion and superior wear resistance compared to the material constituting the housing 12, where the sliding surface 220 is formed.

[0103] Here, ceramic is a material with a small coefficient of linear expansion and minimal dimensional change due to water absorption, and it also exhibits excellent wear resistance. If the drive disc 22 is made of ceramic, the relative positional relationships between the drive disc 22 and the shaft 18, and between the drive disc 22 and the housing 12, are stable. As a result, precise flow control of the fluid can be ensured, and accidental fluid leakage can be suppressed.

[0104] On the drive disk 22, a rotor hole 221 is formed at a position eccentric to the axis CL of the shaft 18. The rotor hole 221 is a through hole that extends along the axial direction DRa. The rotor hole 221 is formed at a location on the drive disk 22 that coincides with the first flow path hole 141 and the second flow path hole 142 in the axial direction DRa when the drive disk 22 is rotated about the axis CL of the shaft 18.

[0105] A shaft insertion hole 223 is formed approximately at the center of the drive disk 22. The shaft insertion hole 223 is a drive-side insertion hole through which the shaft 18 passes. The inner diameter of the shaft insertion hole 223 is formed to be larger than the diameter of the shaft 18 to prevent the shaft 18 from slipping. A first pressing groove 224 and a second pressing groove 225 are formed on the drive disk 22 for pressing a portion of the rod 24 into it.

[0106] When the drive disc 22 is rotated to a position where the rotor bore 221 and the first flow path bore 141 coincide in the axial direction DRa, the valve device 10 opens the first flow path bore 141. Additionally, when the drive disc 22 is rotated to a position where the rotor bore 221 and the second flow path bore 142 coincide in the axial direction DRa, the valve device 10 opens the second flow path bore 142.

[0107] The drive disk 22 is configured to adjust the flow rate ratio of the fluid passing through the first flow path orifice 141 to the fluid passing through the second flow path orifice 142. That is, the drive disk 22 is configured to decrease the opening of the second flow path orifice 142 as the opening of the first flow path orifice 141 increases.

[0108] The lever 24 is a connecting component that connects the drive disk 22 to the shaft 18. The lever 24 is fixed to the drive disk 22 and connects the drive disk 22 and the shaft 18 so that they can rotate as a single unit while allowing the drive disk 22 to be displaced along the axial direction DRa of the shaft 18.

[0109] Specifically, such as Figure 11 As shown, the rod 24 has a disc portion 241, a first arm portion 242, and a second arm portion 243. The disc portion 241, the first arm portion 242, and the second arm portion 243 are integrally formed into a single molded part.

[0110] The disc portion 241 has a central through hole 241a formed at its approximately central portion for the shaft 18 to pass through. The disc portion 241 is sized to not coincide with the shaft through hole 223 in the axial direction DRa. A first arm portion 242 and a second arm portion 243 are connected to the disc portion 241.

[0111] The first arm 242 and the second arm 243 protrude from the disk portion 241 toward the outer side of the radial DRr, respectively. The first arm 242 and the second arm 243 protrude in opposite directions to each other.

[0112] Specifically, a first engaging claw 242a and a second engaging claw 242b protruding in the axial direction DRa are provided on the side of the first arm 242 opposite to the opposing surface of the drive disk 22. The first engaging claw 242a and the second engaging claw 242b are each formed in an L-shape. The first engaging claw 242a and the second engaging claw 242b are formed such that their root side extends along the axial direction DRa and their front end side protrudes in the circumferential direction DRc. The front ends of the first engaging claw 242a and the second engaging claw 242b protrude in a direction away from each other.

[0113] The first engaging pawl 242a engages with the first flange portion 187 of the shaft 18. That is, the first engaging pawl 242a is the engaging portion of the rod 24 that engages with the shaft 18. The first engaging pawl 242a has portions opposing the first flange portion 187 in both the axial direction DRa and the circumferential direction DRc. Furthermore, the first engaging pawl 242a engages with the first flange portion 187 with a gap between it and the first flange portion 187 in the axial direction DRa. Thus, the rod 24 and the drive disc 22 are connected to the shaft 18 in a state where they can be displaced along the axial direction DRa.

[0114] The second engaging pawl 242b is a hook-locking part that engages with the hook portion 302 of the second torsion spring 30. By engaging the hook portion 302 of the second torsion spring 30 with the second engaging pawl 242b, the force of the second torsion spring 30 is applied to the rod 24. Thus, the force of the second torsion spring 30 maintains the abutment state between the first engaging pawl 242a and the first flange portion 187. The first engaging pawl 242a is the abutment portion that contacts the shaft 18.

[0115] On the other hand, a third engaging pawl 243a and a fourth engaging pawl 243b protruding toward the axial direction DRa are provided on the side opposite to the opposing surface of the drive disk 22 in the second arm 243. The third engaging pawl 243a and the fourth engaging pawl 243b are configured in a substantially similar manner to the first engaging pawl 242a and the second engaging pawl 242b.

[0116] The third engaging pawl 243a engages with the second flange portion 188 of the shaft 18. That is, the third engaging pawl 243a is an engaging portion that engages with the abutment portion provided on the shaft 18. The third engaging pawl 243a has portions opposing the second flange portion 188 in both the axial direction DRa and the circumferential direction DRc. Although not shown, the third engaging pawl 243a engages with the second flange portion 188 with a gap between it and the second flange portion 188 in the axial direction DRa. Therefore, the rod 24 and the drive disc 22 are connected to the shaft 18 in a state where they can be displaced along the axial direction DRa.

[0117] Although not shown, protrusions are formed on the opposing surfaces of the first arm portion 242 and the second arm portion 243 that are opposite to the drive disk 22. Each protrusion protrudes toward the drive disk 22 in such a way that it can be pressed into the first pressing groove 224 and the second pressing groove 225 formed on the drive disk 22.

[0118] The rod 24, constructed in this way, is fixed to the drive disk 22 by pressing the protrusions into the respective pressing grooves 224, 225. In this embodiment, the first arm 242 and the second arm 243 of the rod 24 are formed in a point-symmetric manner with respect to the central through hole 241a, and are made into approximately the same shape. Thus, even when the rod 24 is rotated 180° in the circumferential direction DRc, it can still be assembled to the shaft 18 and the drive disk 22.

[0119] Figure 3 , Figure 10 The compression spring 26 shown is a force-applying member that applies force to the rotor 20 against the fixed disk 14. The compression spring 26 elastically deforms along the axial direction DRa of the shaft 18. The compression spring 26 is arranged inside the housing 12 in a compressed state along the axial direction DRa, with one end of the compression spring 26 connected to the shaft 18 and the other end of the compression spring 26 connected to the rotor 20. Specifically, the compression spring 26 is arranged with one end of the compression spring 26 connected to the connecting end face 185a of the inner side of the support portion 182 and the other end of the compression spring 26 connected to the disk portion 241. The compression spring 26 is not fixed relative to at least one of the rotor 20 and the shaft 18, so that the compression spring 26 does not function as a torsion spring.

[0120] By using the compression spring 26 to press the rotor 20 onto the fixed disk 14, the contact state between the opening surface 140 of the fixed disk 14 and the sliding surface 220 of the drive disk 22 can be maintained. This contact state refers to the state in which the opening surface 140 of the fixed disk 14 and the sliding surface 220 of the drive disk 22 are in surface contact. That is, the valve device 10 can maintain the position of the drive disk 22 in a position where it is in contact with the fixed disk 14.

[0121] Specifically, the compression spring 26 is configured to surround the axis CL of the shaft 18. In other words, the shaft 18 is located inside the compression spring 26. Accordingly, the phenomenon that the load of the compression spring 26 on the drive disk 22 is biased on the circumferential DRc of the shaft 18 can be suppressed, thus making it easier to maintain the contact state between the sliding surface 220 and the opening surface 140.

[0122] The first torsion spring 28 is a spring that applies force to the shaft 18 in the circumferential direction DRc about the axis CL of the shaft 18 relative to the housing 12. The first torsion spring 28 is disposed between the housing 12 and the shaft 18. Specifically, the first torsion spring 28 has hook portions 281 and 282 at both ends in the axial direction DRa, which protrude radially outward. For ease of explanation, the hook portion 281 on one side in the axial direction DRa will be referred to as the first hook portion 281 and the hook portion 282 on the other side in the axial direction DRa will be referred to as the second hook portion 282. In this embodiment, the first hook portion 281 constitutes a locking hook portion that engages with the housing 12.

[0123] like Figure 14 , Figure 15 As shown, the second hook 282 is engaged with the first large-diameter locking portion 186b of the support portion 182. Since the second hook 282 is engaged with the first large-diameter locking portion 186b, which is a rotating member, the position of the second hook 282 changes in the circumferential direction DRc when the rotor 20 rotates.

[0124] like Figure 15 As shown, the first hook 281 is engaged with the main body-side locking portion 126 formed on the main body cover portion 124. The main body-side locking portion 126 is composed of a protrusion formed on the inner side of the rib 124b. Since the first hook 281 is engaged with the main body cover portion 124, which is a non-rotating member, the position of the first hook 281 does not change even if the rotor 20 rotates. In this embodiment, the main body-side locking portion 126 is a hook-type locking portion for engaging the first hook 281.

[0125] The first torsion spring 28 is used essentially in a state where it has undergone elastic deformation due to torsion along the circumferential direction DRc. The force of the first torsion spring 28 acts on the shaft 18 whether the shaft 18 is rotating or stationary. Furthermore, the force of the first torsion spring 28 is transmitted as a rotational force from the gear portion 162 of the drive unit 16 to the motor 161 via the shaft 18. Therefore, by distributing the first torsion spring 28 between the housing 12 and the shaft 18, loosening in the circumferential direction DRc between the drive unit 16 and the shaft 18 can be suppressed. In addition, the first torsion spring 28 is only torsion along the circumferential direction DRc, and not compressed along the axial direction DRa.

[0126] Here, the rotational drive range of shaft 18 on the circumferential DRc is explained. The rotational drive range of shaft 18 refers to the range of motion of shaft 18 that it can rotate around the axis CL.

[0127] like Figure 16As shown, the rotational drive range of shaft 18 includes the force-applying range where the first torsion spring 28 applies a force to shaft 18 in the circumferential direction (DRc) and the non-force-applying range where the first torsion spring 28 does not apply a force to shaft 18 in the circumferential direction (DRc). The force-applying range is the range in which the first torsion spring 28 exerts a force on shaft 18 when the second hook portion 282 is in contact with the first large-diameter locking portion 186b. Conversely, the non-force-applying range is the range in which the second hook portion 282 leaves the first large-diameter locking portion 186b and no longer exerts a force on shaft 18 from the first torsion spring 28. Furthermore, the reference position refers to the position where the force of the first torsion spring 28 acting on shaft 18 is minimized when the second hook portion 282 is in contact with the first large-diameter locking portion 186b.

[0128] In this embodiment, the shaft 18 can rotate within a rotational drive range from an initial rotational position to a maximum rotational position. The initial rotational position is the position of the end of the shaft 18 when it rotates in the first rotational direction R1. The maximum rotational position is the position of the end of the shaft 18 when it rotates in the second rotational direction R2. In this embodiment, the positions where the rotation of the shaft 18 is restricted due to contact with the limiting portions 125a and 125b provided in the housing 12 are defined as the initial rotational position and the maximum rotational position.

[0129] like Figure 17 As shown, the position where the shaft 18 contacts the first limiting part 125a when it rotates in the first rotation direction R1 is set as the initial rotation position of the shaft 18. Additionally, as... Figure 18 As shown, the position where the shaft 18 contacts the second limiting part 125b when rotating in the second rotation direction R2 is set as the maximum rotation position of the shaft 18.

[0130] The first torsion spring 28 applies a force to the shaft 18 in a second rotational direction R2 relative to the housing 12 when the shaft 18 is driven by the motor 161 in a first rotational direction R1 and the shaft 18 is in its initial rotational position. That is, the first torsion spring 28 is configured to be torsionally directed in the first rotational direction R1 when in the initial rotational position. Therefore, when the shaft 18 is in its initial rotational position, the force Ft of the first torsion spring 28 acts in the opposite direction to the first rotational direction R1, thus applying a force to the shaft 18 in the second rotational direction R2 relative to the housing 12.

[0131] Here, as Figure 19As shown, the first torsion spring 28 is wound in a first rotational direction R1, starting from the first hook portion 281. A reaction force Fr acts on the first hook portion 281 in a second rotational direction R2. Additionally, a force Ft acts on the first torsion spring 28 at a position opposite the first hook portion 281, separated from the axis CL, in the first rotational direction R1. Thus, the first torsion spring 28 is displaced such that the portion from the first hook portion 281 at approximately 90° along the first rotational direction R1 approaches the axis CL. To keep the first torsion spring 28 in a proper position, a spring guide portion 125 is provided at least within the range from the first hook portion 281 at 90° along the first rotational direction R1.

[0132] Taking this into account, valve device 10, such as Figure 20 As shown, the spring guide 125 is provided at least within a range extending from the first hook 281 to 90° along the first rotation direction R1. The line connecting the locking position of the first hook 281 to the axis CL1 is designated as the first imaginary line IL1, and the line connecting the position on the circumferential DRc where the first hook 281 has rotated 90° along the torsional direction of the first torsion spring 28 to the axis CL is designated as the second imaginary line IL2. At this time, the spring guide 125 is provided at least within the range from the first imaginary line IL1 to the second imaginary line IL2. In other words, the spring guide 125 is at least positioned within the range surrounded by the first torsion spring 28, the first imaginary line IL1, and the second imaginary line IL2. Specifically, the spring guide 125 is provided with a first limiting part 125a at a position where the first imaginary line IL1 has rotated a predetermined angle (e.g., 10° to 30°) along the second rotation direction R2. Furthermore, the spring guide 125 is provided with a second limiting part 125b at a position where it has rotated a predetermined angle (e.g., 10° to 30°) from the second imaginary line IL2 along the first rotation direction R1. The predetermined angle mentioned above is an example and is not limited to the angle described above.

[0133] Furthermore, the valve device 10 is configured such that the shaft 18 can rotate within a range without the spring guide 125. This ensures the rotational drive range of the shaft 18.

[0134] Furthermore, the valve device 10 has a main body-side locking portion 126 at a location on the housing 12. This main body-side locking portion 126 is located on the inner periphery of the rib 124b. The main body-side locking portion 126 protrudes toward the axis CL such that the distance between it and the axis CL is shorter than the distance from the front end of the first hook portion 281 to the axis CL. The distance from the inner periphery of the rib 124b, excluding the main body-side locking portion 126, to the axis CL is approximately equal to the distance from the front end of the first hook portion 281 to the axis CL. Therefore, when the first torsion spring 28 is assembled to the main body cover 124, the first hook portion 281 of the first torsion spring 28 cannot be locked in a location other than the main body-side locking portion 126.

[0135] The second torsion spring 30 is a spring that applies a force to the rod 24 in the circumferential direction DRc relative to the shaft 18. The second torsion spring 30 is disposed between the shaft 18 and the rod 24. Compared with the first torsion spring 28, the second torsion spring 30 has smaller dimensions in the axial direction DRa and in the radial direction DRR.

[0136] The second torsion spring 30 has hook portions 301 and 302 protruding outward in the radial direction DRa at both ends. For ease of explanation, the hook portion 301 on one side of the axial direction DRa will be referred to as the third hook portion 301, and the hook portion 302 on the other side of the axial direction DRa will be referred to as the fourth hook portion 302.

[0137] like Figure 9 As shown, the third hook portion 301 of the second torsion spring 30 is engaged with the second large-diameter locking portion 186c of the bracket portion 182. Additionally, as... Figure 8 As shown, the fourth hook 302 is engaged relative to the second engaging claw 242b of the rod 24.

[0138] The second torsion spring 30 is used essentially in a state where it has undergone elastic deformation due to torsion along the circumferential direction DRc. The force of the second torsion spring 30 acts on the rod 24 whether the shaft 18 is rotating or stationary. Furthermore, the force of the second torsion spring 30 is transmitted as a rotational force to the drive disk 22 via the rod 24. Therefore, by placing the second torsion spring 30 between the shaft 18 and the rod 24, loosening along the circumferential direction DRc between the shaft 18 and the rod 24 can be suppressed. Moreover, since the rod 24 is fixed to the drive disk 22, loosening along the circumferential direction DRc between the shaft 18 and the drive disk 22 can be suppressed using the second torsion spring 30. In addition, the second torsion spring 30 is only torsion along the circumferential direction DRc, and not compressed along the axial direction DRa.

[0139] With the second torsion spring 30 sandwiched between the shaft 18 and the rod 24, the valve device 10 engages the flanges 187 and 188 of the shaft 18 with the rod 24, thereby subdividing the three components.

[0140] The drive unit 16 is a device for outputting rotational force. For example... Figure 3 As shown, it has a motor 161 as a drive source and a gear 162 as a power transmission member that transmits the output of the motor 161 to the shaft 18.

[0141] Within the rotational drive range between the initial rotational position and the maximum rotational position, the drive shaft 18 of the motor 161 rotates in a first rotational direction R1 toward the initial rotational position and a second rotational direction R2 opposite to the first rotational direction R1. The motor 161 is a stepper motor. The motor 161 rotates according to control signals from a motor control unit 163 electrically connected to the motor 161.

[0142] The gear section 162 is a speed reducer that reduces the output of the motor 161. The gear section 162 is composed of a gear mechanism including an output gear 162a. The output gear 162a is as follows... Figure 22 The output gear 162a is formed by an internal gear meshing with the shaft gear 183a. Backlash is provided between the output gear 162a and the shaft gear 183a to prevent locking of the two gears. Backlash is the gap between the pitch circles of the output gear 162a and the shaft gear 183a.

[0143] The motor control unit 163 is a computer that includes a memory, a processor, and other components that serve as a non-temporary physical storage medium. The motor control unit 163 executes a computer program stored in the memory and performs various control processes according to the computer program.

[0144] like Figure 22 As shown, an electromotive force (EMF) measuring unit 164 and a temperature control device 110 for controlling the temperature control device 100 are connected to the input side of the motor control unit 163. The EMF measuring unit 164 is a measuring device that measures the back EMF generated in the coil of the motor 161.

[0145] Here, when the shaft 18 rotates to the initial rotational position under the action of the motor 161, the shaft 18 contacts the first limiting part 125a, and the motor 161 becomes out of step. When the motor 161 becomes out of step, the back electromotive force generated in the coil of the motor 161 changes.

[0146] Based on this phenomenon, the motor control unit 163 determines whether the shaft 18 is in a state of contact with the first limiting part 125a after rotating to the initial rotation position. That is, the motor control unit 163 determines whether the shaft 18 is in a state of contact with the first limiting part 125a after rotating to the initial rotation position based on the back electromotive force measured by the electromotive force measuring unit 164 when the shaft 18 rotates in the first rotation direction R1.

[0147] The motor control unit 163 controls the motor 161 according to requirements from the temperature regulation control device 110, etc. The motor control unit 163 controls the motor 161 while maintaining the position of the shaft 18 relative to the origin position. In this embodiment, the motor control unit 163 performs an initialization process to update the origin position when the shaft 18 rotates to its initial rotation position and contacts the first limiting member 125a. Updating the origin position refers to learning the origin position by integrating the position information of the shaft 18 held by the motor control unit 163 with the actual position of the shaft 18. Details of the initialization process will be described later.

[0148] Next, the operation of the valve device 10 in this embodiment will be explained. For example... Figure 1 , Figure 2 , Figure 3 As shown, the valve device 10 is configured such that fluid flows into the inlet-side space 12d from the inlet portion 12a as indicated by arrow Fi. Furthermore, when the first flow path orifice 141 is open, fluid flows from the inlet-side space 12d through the first flow path orifice 141 to the first outlet-side space. The fluid flowing into the first outlet-side space flows out from the first outlet-side space through the first outlet portion 12b to the outside of the valve device 10 as indicated by arrow F1o. In this case, the flow rate of the fluid through the first flow path orifice 141 is determined by the opening degree of the first flow path orifice 141. That is, the larger the opening degree of the first flow path orifice 141, the larger the flow rate of the fluid flowing from the inlet portion 12a through the first flow path orifice 141 to the first outlet portion 12b.

[0149] On the other hand, when the second flow path orifice 142 is open, fluid flows from the inlet-side space 12d through the second flow path orifice 142 into the second outlet-side space. The fluid flowing into the second outlet-side space flows out from the second outlet-side space through the second outlet portion 12c to the outside of the valve device 10 as shown by arrow F2o. In this case, the flow rate of the fluid through the second flow path orifice 142 is determined by the opening degree of the second flow path orifice 142. That is, the larger the opening degree of the second flow path orifice 142, the larger the flow rate of the fluid flowing from the inlet portion 12a through the second flow path orifice 142 to the second outlet portion 12c.

[0150] Here, the valve device 10 adjusts the opening of each flow path orifice 141, 142 by adjusting the position of the shaft 18 based on the motor 161, thereby adjusting the flow rate of the fluid passing through the valve device 10 to the desired flow rate. In this valve device 10, it is important to improve the learning accuracy of the origin position of the shaft 18 in order to accurately obtain the desired flow rate.

[0151] Therefore, in the valve device 10 of this embodiment, the motor control unit 163 periodically or irregularly performs initialization processing to update the origin position of the shaft 18. (Refer to...) Figure 23 This will explain the initialization process.

[0152] like Figure 23 As shown, in step S100, the motor control unit 163 obtains the measurement result of the back electromotive force generated in the coil of the motor 161 from the electromotive force measuring unit 164. Furthermore, in step S110, the motor control unit 163 determines whether the shaft 18 is in the initial rotational position based on the measurement result of the back electromotive force. That is, the motor control unit 163 determines whether the shaft 18 is in a state where it has rotated to the initial rotational position and is in contact with the first limiting part 125a based on the back electromotive force generated in the coil of the motor 161.

[0153] If the result of the determination process in step S110 is that the shaft 18 is not in the initial rotational position, the motor control unit 163 skips this process. On the other hand, if the shaft 18 is in the initial rotational position, the motor control unit 163 moves to step S120.

[0154] In step S120, the motor control unit 163 updates the origin position of the shaft 18. Specifically, the motor control unit 163 updates the origin position by using the current position of the shaft 18, i.e., the initial rotational position.

[0155] As described above, with the shaft 18 in its initial rotational position, the first torsion spring 28 applies a force to the shaft 18 in the second rotational direction R2 relative to the housing 12. This suppresses the positional deviation of the shaft 18 caused by backlash, thus allowing the origin position of the shaft 18 to be appropriately updated through the aforementioned initialization process.

[0156] In the valve device 10 described above, in order to implement high-precision position control of the shaft 18 (i.e., opening control of each flow path orifice 141, 145), it is important to improve the control position accuracy based on loosening suppression on the circumferential DRc and the learning accuracy of the origin position of the shaft 18.

[0157] To address this, the valve device 10 utilizes the first torsion spring 28 to apply force to the shaft 18 in the circumferential DRc relative to the housing 12. This suppresses any loosening in the circumferential DRc between the drive unit 16 and the shaft 18.

[0158] Furthermore, the valve device 10 applies force to the rod 24 in the circumferential DRc relative to the shaft 18 using the second torsion spring 30. This suppresses any loosening in the circumferential DRc between the shaft 18 and the rod 24. Moreover, since the rod 24 is fixed to the drive disc 22, the second torsion spring 30 can suppress any loosening in the circumferential DRc between the shaft 18 and the drive disc 22.

[0159] Therefore, by suppressing the loosening on the circumferential DRc from the drive section 16 to the rotor 20, the opening deviation of each flow path hole 141, 142 caused by the loosening can be suppressed.

[0160] Furthermore, the limiting portions 125a and 125b for restricting the rotation of the shaft 18 are provided inside the first torsion spring 28. Therefore, when the shaft 18 contacts the limiting portions 125a and 125b, accidental deflection of the housing 12 and the shaft 18 can be suppressed. Thus, when learning the origin position with the shaft 18 in contact with the first limiting portion 125a, the position can be accurately aligned, thereby improving the learning accuracy of the origin position of the shaft 18. In other words, when the shaft 18 contacts the first limiting portion 125a, accidental deflection of the housing 12 and the shaft 18 can be suppressed, and opening deviations of the flow path holes 141 and 142 caused by accidental deflection of the shaft 18, etc., can be suppressed.

[0161] In addition, the valve device 10 of this embodiment can achieve the following effects, for example.

[0162] (1) The housing 12 includes a spring guide 125 arranged inside the first torsion spring 28 in a manner surrounding the shaft CL. Limiting portions 125a and 125b are formed at the ends of the spring guide 125 along the circumferential DRc. Thus, if the structure is designed to limit the rotational drive range of the shaft 18 using the ends of the spring guide 125 along the circumferential DRc, it results in a simpler structure compared to a case where the spring guide 125 and each limiting portion 125a and 125b are formed separately. This contributes to the miniaturization of the valve device 10.

[0163] (2) The spring guide 125 is provided at least in the range from the first imaginary line IL1 to the second imaginary line IL2. In this way, if the spring guide 125 is provided in the range where the first torsion spring 28 can easily move close to the axis CL, the first torsion spring 28 can be restricted to a proper position by means of the spring guide 125.

[0164] Furthermore, by arranging the spring guide 125 within the necessary minimum range, the first torsion spring 28 can be restrained in a proper position while simultaneously expanding the rotational drive range of the shaft 18. In this case, the degree of freedom for valve opening indication is increased, thereby enhancing its value as a valve device 10.

[0165] (3) On the housing 12, a main body side locking part 126 for locking the first hook 281 of the first torsion spring 28 is provided at a location on the circumferential DRc. Accordingly, since there is only one location on the housing 12 where the first hook 281 can be locked, it is possible to prevent the misassembly of the first torsion spring 28 such that the first hook 281 is locked in an unexpected position.

[0166] (4) When the valve device 10 is in the initial rotational position, it applies a force to the shaft 18 relative to the housing 12 in the second rotational direction R2. As a result, high-precision position control of the shaft 18 (i.e., opening control of each flow path orifice 141, 142) can be implemented from the initial rotational position.

[0167] (5) The drive unit 16 includes a motor control unit 163 that controls the motor 161 while maintaining the position of the shaft 18 with reference to the origin position. The motor control unit 163 performs an initialization process to update the origin position when the shaft 18 rotates to the initial rotation position and contacts the first limiting part 125a. As a result, high-precision position control of the shaft 18 starting from the initial rotation position can be implemented.

[0168] (6) Specifically, the motor 161 is a stepper motor. Furthermore, the motor control unit 163 determines whether the shaft 18 is in contact with the first limiting part 125a based on the back electromotive force generated in the coil of the motor 161. In this way, if a stepper motor with excellent position accuracy is used, high-precision position control of the shaft 18 (i.e., opening control of each flow path hole 141, 142) can be implemented from the initial rotational position.

[0169] (7) The shaft 18 includes: a metal shaft core 181 containing a shaft core CL and extending along the axial direction DRa; and a resin support portion 182 connected to the shaft core 181 and bearing the force of each torsion spring 28, 30. Accordingly, compared with the case where the shaft 18 is entirely made of resin material, the rigidity and accuracy (i.e., straightness) of the shaft 18 can be ensured. In addition, by making the support portion 182 made of resin, a lightweight and complex-shaped shaft 18 can be achieved. In particular, by ensuring the straightness of the shaft 18, the clearance of the bearing portion 124g, etc., can be reduced, and thus the positional displacement of the shaft 18 in the radial direction (i.e., radial DRr) can be suppressed.

[0170] (8) Shaft 18 passes through the fixed disk 14 and the drive disk 22 and is rotatably supported on the housing 12. Thus, if the structure is configured such that shaft 18 passes through both the fixed disk 14 and the drive disk 22, the fixed disk 14 and the drive disk 22 can be aligned using shaft 18, which is a single component. This suppresses radial displacement of the fixed disk 14 and the drive disk 22. This is effective in suppressing opening deviations of the flow path holes 141 and 142.

[0171] (9) The rotational drive range of the shaft 18 on the circumferential DRc includes the force-applying range of the first torsion spring 28 applying force to the shaft 18 in the circumferential DRc and the non-force-applying range of the first torsion spring 28 not applying force to the shaft 18 in the circumferential DRc. Accordingly, for example, when assembling the first torsion spring 28 to the housing 12 and the shaft 18, by setting the rotational position of the shaft 18 to the non-force-applying range, it is not necessary to assemble the first torsion spring 28 in a torsional state. In addition, by rotating the shaft 18 to a certain extent after the first torsion spring 28 is assembled, the torsional elastic deformation of the first torsion spring 28 is obtained.

[0172] (10) In the valve device 10, the drive disc 22 is connected to the shaft 18 in a state that allows it to be displaced along the axial direction DRa of the shaft 18. Therefore, even if a second torsion spring 30 is provided between the shaft 18 and the rod 24, the sliding surface 220 of the drive disc 22 and the surface contact of the fixed disc 14 can be maintained well.

[0173] (11) Here, if a single torsion spring is used to suppress loosening on the circumferential DRc from the drive unit 16 to the rotor 20, the force of the torsion spring becomes too large, thus increasing the load on the drive unit 16 cannot be avoided. In contrast, if a structure is adopted to suppress loosening on the circumferential DRc from the drive unit 16 to the rotor 20 using both the first torsion spring 28 and the second torsion spring 30, the force of each torsion spring 28 and 30 can be suppressed. As a result, the increase in the load on the drive unit 16 can be suppressed.

[0174] (Second Implementation)

[0175] Next, refer to Figure 24 The second embodiment will now be described. In this embodiment, the difference from the first embodiment is the addition of a protrusion 125c to the spring guide 125. In this embodiment, the differences from the first embodiment will be primarily described.

[0176] like Figure 24 As shown, a protrusion 125c protruding in a direction away from the axis CL is provided in the spring guide portion 125. The protrusion 125c is provided at the end of the spring guide portion 125 where the second limiting portion 125b is located. The spring guide portion 125 contacts the first torsion spring 28 through the protrusion 125c protruding in a direction away from the axis CL.

[0177] Everything else is the same as in the first embodiment. The valve device 10 of this embodiment can achieve the same effects as the first embodiment achieved by a structure common to or equivalent to that of the first embodiment.

[0178] Furthermore, the following effects can be obtained according to this embodiment.

[0179] (1) A protrusion 125c protruding in a direction away from the axis CL is provided in the spring guide portion 125. As a result, the thickness of the part that guides the first torsion spring 28 is increased, which can sufficiently ensure the strength of the spring guide portion 125. In addition, if the structure is designed so that the protrusion 125c contacts the first torsion spring 28, the center of the first torsion spring 28 can be brought closer to the axis CL of the shaft 18, so that the first torsion spring 28 can be guided to a more appropriate position.

[0180] While increasing the overall thickness of the spring guide 125 can improve its strength, this would increase the weight of the housing 12. Therefore, it is preferable to add a protrusion 125c to the spring guide 125.

[0181] (First variation of the second embodiment)

[0182] In the second embodiment, a structure in which a protrusion 125c is provided in the spring guide 125 is illustrated, but the spring guide 125 is not limited to this. The spring guide 125 may also be, for example, as shown in... Figure 25 As shown, three protrusions 125c, 125d, and 125e are provided. In Figure 25 In the example shown, the protrusion 125d is provided at the end of the spring guide 125 where the first limiting part 125a is located. Additionally, the protrusion 125e is provided at the middle of each limiting part 125a in the spring guide 125. Furthermore, the number of protrusions can be arbitrarily set.

[0183] (Second variation of the second embodiment)

[0184] In the second embodiment, a structure is illustrated in which a protrusion 125c is provided in the arc-shaped portion of the spring guide 125, but the spring guide 125 is not limited to this. The spring guide 125 may, for example, be as follows: Figure 26 As shown, the arc-shaped portion is omitted, and it is composed of three protrusions 125c, 125d, and 125e. These three protrusions 125c, 125d, and 125e are the same as those in the first modified example described above.

[0185] Here, the spring guide 125 only needs to have protrusions 125c and 125d that constitute each limiting part 125a and 125b, and the protrusion 125e can also be omitted. In addition, the number of protrusions can be set arbitrarily.

[0186] (Other implementation methods)

[0187] The above describes representative embodiments of the present disclosure, but the present disclosure is not limited to the embodiments described above. Furthermore, the components of the valve device 10 are not limited to the components described above, and may differ from the components described above.

[0188] The spring guide portion 125 in the above embodiment is composed of a continuous arc-shaped curved portion, but it is not limited to this. For example, it can also be composed of a structure in which multiple columnar members are arranged in an arc shape at predetermined intervals.

[0189] It is desirable that the limiting portions 125a and 125b be formed at the ends of the spring guide portion 125 in the circumferential direction DRc, as in the embodiment described above, but this is not a limitation. For example, they may be formed by components different from the spring guide portion 125. In this case, the spring guide portion 125 is not necessary and may be omitted.

[0190] It is desirable to provide a portion on the housing 12 that can lock the first hook 281, as in the embodiment described above, but it is not limited to this and multiple portions that can lock the first hook 281 may also be provided.

[0191] Initialization processing can also be performed, for example, when shaft 18 has rotated to its maximum rotation position and is in contact with the second limiting part 125b. Furthermore, motor 161 can also be, for example, a servo motor. Alternatively, it can be determined whether shaft 18 is in contact with the first limiting part 125a based on the output of a position sensor used to detect the rotational position of motor 161.

[0192] It is desirable that the shaft 18 has a metal core portion 181 and a resin support portion 182 as described in the above embodiment, but it is not limited thereto. For example, the shaft 18 may also be configured such that the core portion 181 and the support portion 182 are made of either a metal material or a resin material.

[0193] It is desirable that the valve device 10 includes a second torsion spring 30 as described in the above embodiment, but it is not limited thereto and the second torsion spring 30 may be omitted.

[0194] In the above embodiment, a structure is illustrated in which both ends of the shaft 18 are rotatably supported on the housing 12, but the valve device 10 is not limited to this. For example, the valve device 10 may also be configured such that one end of the shaft 18 is rotatably supported on the fixed plate 14. Alternatively, the valve device 10 may also be configured such that only one end of the shaft 18 is rotatably supported on the housing 12.

[0195] In the above embodiment, a compression spring 26 applies force to the rotor 20 against the fixed disk 14, but the valve device 10 is not limited to this. For example, the valve device 10 may also utilize a cylindrical elastic body that elastically deforms along the axial direction DRa of the shaft 18 to apply force to the rotor 20 against the fixed disk 14. Alternatively, the valve device 10 may utilize the pressure difference between the inlet-side space 12d and the outlet-side space 12e to apply force to the rotor 20 against the fixed disk 14. As shown above, the compression spring 26 is not an essential component in the valve device 10.

[0196] It is desirable that the valve device 10 be configured to include a non-force-applying range within the rotational drive range of the shaft 18, as described in the above-described embodiment, but this is not a limitation. The valve device 10 may also be configured to exclude the non-force-applying range within the rotational drive range of the shaft 18.

[0197] It is desirable that the valve device 10 has a locking part on the rod 24 that engages with the shaft 18 when the second torsion spring 30 is sandwiched between the rod 24 and the shaft 18, as in the embodiment described above. However, it is also possible that the locking part is not provided.

[0198] In the above embodiments, the valve device 10 is exemplified as a structure composed of a three-way valve, but the valve device 10 is not limited to a three-way valve. The valve device 10 of this disclosure may also be configured as a flow regulating valve or an on / off valve having one fluid inlet and one fluid outlet. In this case, a flow path orifice is formed in the fixed plate 14. The valve device 10 of this disclosure may also be configured as a multi-way valve having one fluid inlet and three or more fluid outlets, a multi-way valve having three or more fluid inlets and one fluid outlet, or a multi-way valve having multiple fluid inlets and multiple fluid outlets, etc.

[0199] In the above embodiments, an example of applying the valve device 10 of this disclosure to a vehicle control valve mounted on a vehicle has been described, but the valve device 10 can also be applied to control valves of other devices besides vehicles.

[0200] In the above embodiments, the elements constituting the embodiments are not necessarily essential elements, except where they are specifically stated to be necessary or are clearly considered to be necessary in principle.

[0201] In the above embodiments, when referring to the number, value, quantity, range, or other values ​​of the constituent elements of the embodiments, they are not limited to that specific number, except where they are specifically indicated as necessary or where they are clearly limited to a specific number in principle.

[0202] In the above embodiments, when referring to the shape, positional relationship, etc. of the constituent elements, the shape, positional relationship, etc. are not limited to such shape, positional relationship, etc., except as specifically stated or as limited to a specific shape, positional relationship in principle.

[0203] The control unit and method of this disclosure can be implemented using a dedicated computer provided by means of a processor and memory programmed to perform one or more functions embodied in a computer program. The control unit and method of this disclosure can also be implemented using a dedicated computer provided by means of a processor constructed using one or more dedicated hardware logic circuits. The control unit and method of this disclosure can also be implemented using one or more dedicated computers configured by a combination of a processor and memory programmed to perform one or more functions and a processor constructed by one or more hardware logic circuits. Additionally, the computer program can also be stored as instructions executable by the computer on a computer-readable, non-transitory tangible storage medium.

Claims

1. A valve device, characterized in that, have: The shell has internal fluid passages for fluid flow; A flow path forming part, which is fixed to the inner side of the housing, has at least one flow path hole for fluid to pass through; The drive unit outputs rotational force; A shaft that rotates about a predetermined axis center by the rotational force; The rotor, which increases or decreases the opening of the flow path orifice in conjunction with the rotation of the shaft; as well as A torsion spring, which is arranged to surround the axis and applies a force to the axis circumferentially about the axis relative to the housing. The housing is provided with a limiting part that abuts against the shaft when the shaft rotates to a predetermined position to limit the rotational drive range of the shaft. The limiting part is located inside the torsion spring.

2. The valve device according to claim 1, characterized in that, The housing includes a spring guide disposed inside the torsion spring in a manner that surrounds the axis, and the limiting portion is formed at the circumferential end of the spring guide.

3. The valve device according to claim 2, characterized in that, The torsion spring has a locking hook portion that is locked relative to the housing. When the line connecting the locking position of the locking hook in the housing to the axis is designated as the first imaginary line, and the line connecting the position rotating 90° in the circumferential direction from the locking position along the torsion direction of the torsion spring to the axis is designated as the second imaginary line, The spring guide is provided at least within the range from the first imaginary line to the second imaginary line.

4. The valve device according to claim 3, characterized in that, On the housing, a hook locking part is provided at a location in the circumferential direction to lock the locking hook part.

5. The valve device according to any one of claims 2 to 4, characterized in that, The spring guide includes at least one protrusion that projects away from the axis.

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