Electric valve

Abstract

To provide a technique for a motor valve having a plurality of planetary gear mechanisms as a speed reduction mechanisms to suppress the breakage of gears of the planetary gear mechanisms.SOLUTION: A motor valve 10 includes a feed screw mechanism 24 for moving forward and backward a valve element 22 relative to a valve seat 20 in the axial direction, a rotor 42 rotatably supported on the inner periphery part of a can 48 and adapted to be rotationally driven by a stator 36 arranged on the outer periphery part of the can 24, and a speed reduction device 50 having a plurality of planetary gear mechanisms 52 arranged in the axial direction for transmitting torque to the plurality of planetary gear mechanisms 52 in sequence from the side far from the feed screw mechanism 24 to the side close to the feed screw mechanism 24, and transmitting it to the feed screw mechanism 24 while reducing the rotating sped of the rotor 42, and reduction means for reducing a pressure to work on the gears of a third planetary gear mechanism 52C.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] In the motor-operated valve with a reduction gear disclosed in Patent Document 1, a valve stem with a valve disc is inserted into the motor-operated valve body. A rotor is mounted inside a can fixed to the body, and a reduction gear is housed inside the rotor. The output of the rotor is input to the sun gear and transmitted to the planetary gear. The planetary gear simultaneously meshes with a fixed gear and an output gear, reducing and driving the output gear at a large reduction ratio. The output of the output gear is transmitted to the screw shaft via the driver, converted into linear motion, and transmitted to the valve stem. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-226369 Summary of the Invention [Problem to be solved by the invention]

[0004] In an electric valve that has multiple planetary gear mechanisms as a reduction device that transmits torque to a feed screw mechanism, there is a concern that the gear of the planetary gear mechanism located closest to the feed screw mechanism may be damaged, making it impossible to open or close the electric valve.

[0005] In order to alleviate the above concerns, the present disclosure aims to provide technology for an electric valve that has multiple planetary gear mechanisms as reduction devices and that suppresses damage to gears in the planetary gear mechanism located closest to the feed screw mechanism. [Means for solving the problem]

[0006] The first aspect of the motor-operated valve comprises a valve body having a valve chamber and a valve seat, a cylindrical can extending in the axial direction and arranged on one side of the valve body in the axial direction, a valve element arranged in the valve chamber, a feed screw mechanism that moves the valve element back and forth in the axial direction relative to the valve seat, a rotor rotatably supported on the inner periphery of the can, and a reduction device having a plurality of planetary gear mechanisms arranged in the axial direction, which transmits torque in sequence from the side of the planetary gear mechanisms farthest from the feed screw mechanism to the side closest to the feed screw mechanism, reducing the rotational speed of the rotor and transmitting the torque to the feed screw mechanism, and a reduction means for reducing the pressure acting on the gear of the planetary gear mechanism arranged closest to the feed screw mechanism.

[0007] In an electrically operated valve equipped with a reduction gear device having multiple planetary gear mechanisms, the gear of the planetary gear mechanism located closest to the feed screw mechanism generally receives the greatest torque. This electrically operated valve is equipped with a pressure reducing device that reduces the pressure of the planetary gear mechanism located closest to the feed screw mechanism among the multiple planetary gear mechanisms. As a result, this electrically operated valve provides an electrically operated valve in which damage to the reduction mechanism is suppressed compared to when the planetary gear mechanism located closest to the feed screw mechanism in a reduction gear device having multiple planetary gear mechanisms is the same as the other planetary gear mechanisms.

[0008] The electric valve of the second aspect is the electric valve described in the first aspect, wherein the reduction means is configured such that the gear specifications of the planetary gear mechanism located farthest from the feed screw mechanism and the planetary gear mechanism located closest to the feed screw mechanism are different from each other.

[0009] In this motor-operated valve, the reduction means has different gear specifications for the planetary gear mechanism located farthest from the feed screw mechanism and the planetary gear mechanism located closest to the feed screw mechanism, and the pressure of the planetary gear mechanism located closest to the feed screw mechanism is reduced. As a result, this motor-operated valve provides a motor-operated valve in which damage to the reduction mechanism is suppressed compared to a reduction gear device having multiple planetary gear mechanisms in which the gear specifications of the planetary gear mechanism located closest to the feed screw mechanism are the same as those of the other planetary gear mechanisms.

[0010] A third aspect of the motor-operated valve is the motor-operated valve described in the second aspect, wherein the planetary gear mechanism inputs torque to the sun gear and outputs torque from the planet carrier, and among the axially adjacent planetary gear mechanisms, one planetary gear mechanism located closer to the feed screw mechanism has a larger tooth width between the sun gear and the planet gear than the other planetary gear mechanism located farther from the feed screw mechanism.

[0011] In this motor-operated valve, the one planetary gear mechanism located closer to the feed screw mechanism has a larger face width between the sun gear and the planet gears than the other planetary gear mechanism located farther from the feed screw mechanism, so the pressure generated in the gears of the one planetary gear mechanism is reduced, thereby preventing damage to the one planetary gear mechanism.

[0012] The fourth aspect of the motor-operated valve is the motor-operated valve according to the second or third aspect, in which the planetary gear mechanism located closest to the feed screw mechanism has a larger face width between the sun gear and the planetary gears than the planetary gear mechanism located farthest from the feed screw mechanism.

[0013] In this motor-operated valve, the gear of the planetary gear mechanism located closest to the feed screw mechanism has a larger face width between the sun gear and planet gears than the gear of the planetary gear mechanism located farthest from the feed screw mechanism. As a result, pressure generated in the gear of the planetary gear mechanism located closest to the feed screw mechanism is lower than that in the gear of the planetary gear mechanism located farthest from the feed screw mechanism. Therefore, this motor-operated valve prevents damage to the planetary gear mechanism located closest to the feed screw mechanism.

[0014] The fifth aspect of the motor-operated valve is the motor-operated valve described in the second aspect, wherein the plurality of planetary gear mechanisms input torque to the sun gear and output torque from the planetary carrier, and among the axially adjacent planetary gear mechanisms, one planetary gear mechanism located closer to the feed screw mechanism has a larger module than the other planetary gear mechanism located farther from the feed screw mechanism.

[0015] In this motor-operated valve, the one planetary gear mechanism located closer to the feed screw mechanism has a larger gear module than the other planetary gear mechanisms, which reduces the pressure generated in the gears of the one planetary gear mechanism, thereby preventing damage to the one planetary gear mechanism.

[0016] The sixth aspect of the motor-operated valve is the motor-operated valve described in the second or fifth aspect, wherein the planetary gear mechanism located closest to the feed screw mechanism has a larger module than the planetary gear mechanism located farthest from the feed screw mechanism.

[0017] In this motor-operated valve, the planetary gear mechanism located closest to the feed screw mechanism has a larger module than the planetary gear mechanism located farthest from the feed screw mechanism, so the teeth of the planetary gear mechanism located closest to the feed screw mechanism have greater impact resistance than the gear teeth of the other planetary gear mechanisms. Therefore, with this motor-operated valve, damage to the planetary gear mechanism located closest to the feed screw mechanism is suppressed.

[0018] The seventh aspect of the electric valve is the electric valve described in the first aspect, wherein the reduction means is configured such that the planetary gear mechanism arranged closest to the feed screw mechanism has a planet carrier that inputs torque and a sun gear that outputs torque.

[0019] In this motor-operated valve, the gears of the planetary gear mechanism located closest to the feed screw mechanism have a planet carrier that inputs torque and a sun gear that outputs torque. This reduces the pressure generated in the gears of the planetary gear mechanism located closest to the feed screw mechanism. Therefore, this motor-operated valve prevents damage to the planetary gear mechanism located closest to the feed screw mechanism.

[0020] An eighth aspect of the motor-operated valve is the motor-operated valve according to any one of the first to seventh aspects, further comprising a stator disposed on an outer periphery of the can and configured to rotate the rotor. [Effects of the Invention]

[0021] According to the present invention, in an electric valve having multiple planetary gear mechanisms as a reduction device, a technology for an electric valve is provided that suppresses damage to the gears in the planetary gear mechanism located closest to the feed screw mechanism. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a cross-sectional view illustrating a motor-operated valve according to a first embodiment. FIG. [Figure 2] FIG. 2 is an enlarged view of a reduction gear transmission in the motor-operated valve according to the first embodiment. [Figure 3] FIG. 6 is an enlarged view of a reduction gear transmission in a motor-operated valve according to a second embodiment. [Figure 4] FIG. 10 is an enlarged view of a reduction gear transmission in a motor-operated valve according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0023] An example of an embodiment of the present disclosure will be described below with reference to the drawings. In each drawing, the same or equivalent components and parts are designated by the same reference numerals. Furthermore, the dimensional proportions in the drawings are exaggerated for the sake of explanation and may differ from the actual proportions.

[0024] In addition, in the embodiment of the present disclosure, the axial direction refers to the direction in which the shaft body 44 of the reduction gear transmission 50 extends.

[0025] [First embodiment] (composition) 1 and 2, a motor-operated valve 10 according to a first embodiment of the present disclosure will be described. The motor-operated valve 10 is used, for example, to adjust the flow rate of a fluid (refrigerant) in the refrigeration cycle of an air conditioner or the like. As shown in FIGS. 1 and 2, the motor-operated valve 10 according to this embodiment adjusts the flow rate of a fluid flowing from an inlet 11 connected to a valve body 14 to an outlet 12 by adjusting the opening amount of an opening 18. The motor-operated valve 10 according to this embodiment includes the valve body 14, a valve element 22, an adjustment mechanism 21, and a drive mechanism 33.

[0026] (Valve body 14) As shown in Fig. 1, the valve body 14 is a substantially cylindrical body with an inlet 11 formed on one side thereof. The various components described above that drive the valve element 22 are located on one axial side (the upper side in Fig. 1), and an outlet pipe 82 is connected to an outlet 12 on the other axial side (the lower side in Fig. 1). The inlet 11 is located on one radial side (the left side in Fig. 1) of the valve body 14, and an inlet pipe 80 is connected to the inlet 11. The valve element 22 is accommodated in a valve chamber 16, which is a space formed inside the valve body 14, and is axially drivable by a drive mechanism 33. An opening 18, which has a smaller diameter than the outlet 12, is formed between the valve chamber 16 and the outlet 12. The periphery of the opening 18 is a valve seat 20 that comes into contact with the valve element 22, which will be described later. The valve element 22 adjusts the opening amount of the opening 18 (the flow path area through which the fluid flows), as will be described later.

[0027] (Adjustment mechanism 21) The adjustment mechanism 21 is arranged in the valve chamber 16 and includes a valve element 22 that adjusts the opening amount of the opening 18, a guide portion 23 that guides the valve element 22, a plunger 30 connected to one axial side of the valve element 22, and a feed screw mechanism 24 that is arranged on one axial side of the plunger 30.

[0028] 1, the valve element 22 is a substantially cylindrical member extending in the axial direction, and the outer diameter on the other axial side is larger than the inner diameter of the opening 18. The part on the other axial side abuts against the valve seat 20 to close the opening 18, thereby separating the valve chamber 16 and the outlet port 12. In other words, the valve element 22 is arranged so as to be able to open and close the opening 18.

[0029] 1, the guide portion 23 is a stepped cylindrical member whose other axial end is reduced in diameter, and is fixed to one axial side of the valve chamber 16 in the valve body 14. The inner circumferential surface of the reduced-diameter portion of the guide portion 23 comes into contact with the valve disc 22, guiding the axial movement of the valve disc 22. In addition, a compression coil spring 32 is housed on one axial side of the reduced-diameter portion of the guide portion 23, and supports the other axial side of the compression coil spring 32.

[0030] The plunger 30 is a member that grips one axial side of the valve body 22 on the other axial side, and is urged toward one axial side relative to the guide portion 23 by a compression coil spring 32 disposed radially outward. Furthermore, the plunger 30 is in contact with the spindle 26 of the feed screw mechanism 24 via a ball on one axial side, as will be described later.

[0031] As will be described later, the feed screw mechanism 24 converts torque output from a reduction gear 50 included in a drive mechanism 33 disposed on one axial side of the valve body 14 into axial linear motion. As shown in Fig. 1, the feed screw mechanism 24 has a nut 28 fixed to the valve body 14, and a spindle 26 disposed radially inside the nut 28 and receiving the torque output from the reduction gear 50 on one axial side.

[0032] As shown in FIG. 1, the nut 28 is a substantially cylindrical member having a female screw formed on its radially inner circumferential surface, and the spindle 26 is in rotatable contact with the female screw.

[0033] The spindle 26 is a generally cylindrical member that extends in the axial direction and has a male thread formed on the other axial side that engages with the female thread of the nut 28. When the spindle 26 receives torque from one axial side and rotates around the central axis O of the shaft body 44, it undergoes linear motion in the axial direction while being guided by the female thread of the nut 28. The spindle 26 also transmits linear motion to the plunger 30 by contacting the plunger 30 via a ball on the other axial side. Note that the shape of the spindle 26 is not particularly limited as long as it is capable of receiving the torque output from the reduction gear device 50 and moving in the axial direction. However, in the present embodiment, as an example, serrations are formed on one axial end.

[0034] (Drive mechanism 33) As shown in FIGS. 1 and 2, the drive mechanism 33 includes a cover 46, a can 48, the motor 34, the shaft 44, and a reduction gear 50.

[0035] The cover 46 is disposed on one axial side of the valve body 14, and is a member that covers the motor 34, the can 48, and the reduction gear 50, as will be described later.

[0036] 1 and 2, the can 48 is a cylindrical member extending in the axial direction, and accommodates the rotor 42, shaft support member 45, shaft body 44, and reduction gear 50 (described later) therein, and is joined to the valve body 14 on the other axial side by means of a joining material 49. One axial side of the can 48 is closed in a bag-like shape, and in this embodiment, Haki The can 48 is also a member that covers the valve body 14 from one axial side. The can 48 may be made of any material that does not block magnetic fields, but as an example, it is made of an aluminum alloy.

[0037] 1 and 2, the shaft support member 45 is fixed to the can 48 at one axial side inside the can 48. The shaft support member 45 non-rotatably supports one end in the axial direction of a shaft body extending from one axial side to the other side of the drive mechanism 33. The shaft body 44 is a member that determines the rotational axis of the motor 34 and the reduction gear device 50. The shaft body 44 in this embodiment also rotatably supports the spindle 26 of the feed screw mechanism 24.

[0038] The motor 34 is, for example, a claw-pole stepping motor whose rotation angle and speed are controlled by a driver (not shown). The motor 34 is composed of a stator 36 disposed outside a can 48 and a rotor 42 disposed inside the can 48.

[0039] 1 is shown with the stator 36 disposed outside the can 48, the stator 36 is easily attached to and detached from the can 48, and the motor-operated valve 10 is often sold with the stator 36 removed. Therefore, the motor-operated valve 10 in this disclosure includes both a state in which the stator 36 is not provided and a state in which the stator 36 is provided.

[0040] The stator 36 is an example of a rotating means according to the present disclosure that rotates the rotor 42. As shown in FIG. 1 , the stator 36 includes an A-phase stator 36A and a B-phase stator 36B, which are coaxially arranged side by side in the axial direction on the outer periphery of the can 48. The number of coils included in the stator 36 is determined appropriately based on the specifications of the motor-operated valve 10 and the motor 34. The stator 36 in this embodiment may be configured to be separable from the can 48. That is, the motor-operated valve 10 according to the present disclosure may not include the stator 36. In this configuration, for example, the stator 36 and the parts of the motor-operated valve 10 other than the stator 36 can be shipped separately, and then assembled into the motor-operated valve 10 at the user's site. In this configuration, for example, the stator 36 can be replaced with one having different specifications.

[0041] The rotor 42 is a member that is rotationally driven by a rotating means, and has a plurality of permanent magnets 41 that extend in the axial direction and have south and north poles arranged alternately in the circumferential direction, and is disposed radially inside the stator 36 on the inner periphery of the can 48 so as to be rotatable relative to the shaft 44. The permanent magnets 41 are also fixed radially inside to be rotatable relative to the first sun gear 54A, which is the torque input side of the reduction gear 50 described below, and the shaft 44. When the coils of the A-phase stator 36A and the B-phase stator 36B are excited, the permanent magnets 41 disposed on the rotor 42 are attracted to or repelled by the coils, and are rotationally driven in the circumferential direction.

[0042] (Decelerator 50) As shown in FIG. 1 , the reduction gear device 50 is a component that is coaxial with the rotor 42, has multiple planetary gear mechanisms 52 arranged in the axial direction, and reduces the rotational speed of the rotor 42 to transmit torque to the feed screw mechanism 24. In this embodiment, the reduction gear device 50 has three planetary gear mechanisms 52 that are adjacent to each other in the axial direction: a first planetary gear mechanism 52A, a second planetary gear mechanism 52B, and a third planetary gear mechanism 52C. In other words, the first planetary gear mechanism 52A is an example of the "planetary gear mechanism 52 arranged farthest from the feed screw mechanism 24" in the present disclosure, and the third planetary gear mechanism 52C is an example of the "planetary gear mechanism 52 arranged closest to the feed screw mechanism 24." In other words, the second planetary gear mechanism 52B is an example of the "planetary gear mechanism 52 arranged farthest from the feed screw mechanism 24" relative to the third planetary gear mechanism 52C. The first planetary gear mechanism 52A is an example of "one planetary gear mechanism 52 arranged on the side farther from the feed screw mechanism 24" relative to the second planetary gear mechanism 52B and the third planetary gear mechanism 52C. Similarly, the second planetary gear mechanism 52B is an example of "another planetary gear mechanism 52 arranged on the side closer to the feed screw mechanism 24" relative to the first planetary gear mechanism 52A. The third planetary gear mechanism 52C is an example of "another planetary gear mechanism 52 arranged on the side closer to the feed screw mechanism 24" relative to the first planetary gear mechanism 52A and the second planetary gear mechanism 52B.

[0043] In the description of this embodiment, when the planetary gear mechanisms 52 need to be distinguished from one another, they are distinguished by adding A, B, or C to the end of their reference numerals. The first planetary gear mechanism 52A, the second planetary gear mechanism 52B, and the third planetary gear mechanism 52C each have a sun gear 54, a planet gear 56, a planet carrier 58, and an internal gear 60. Similarly, when the components of each planetary gear mechanism 52 need to be particularly distinguished, they are distinguished by adding A, B, or C to the end of their reference numerals. Note that all of the planetary gear mechanisms 52 in this embodiment are 2K-H type gear mechanisms.

[0044] The sun gear 54 is rotatably supported by the shaft body 44. A plurality of planetary gears 56 mesh with the sun gear 54 and the internal gear 60 and are provided in the circumferential direction. These plurality of planetary gears 56 are rotatably supported by the planet carrier 58. The first sun gear 54A is formed integrally with the other axial side of the rotor 42 (a flat-plate bearing portion on one axial side supported by the shaft body 44). The second sun gear 54B is formed integrally with the other axial side of the first planetary carrier 58A. The third sun gear 54C is formed integrally with the other axial side of the second planetary carrier 58B. As shown in FIGS. 1 and 2, the planetary carrier 58 is provided with three planetary gears 56, for example. In FIGS. 1 and 2, the planetary carrier 58 and the planetary gears 56 are shown in rotational cross-section, which differs from the actual situation.

[0045] In addition, the third planetary carrier 58C has a hole on the other axial side with a groove formed on the radial inside that engages with the spindle 26 (serrated portion), and torque can be transmitted by the third planetary carrier 58C engaging with the spindle 26.

[0046] 2, in this embodiment, the internal gear 60 is a single member, and is a single gear with internal teeth formed continuously in the axial direction. In other words, the first internal gear 60A, the second internal gear 60B, and the third internal gear 60C each refer to different axial portions of the single internal gear 60. However, the internal gear 60 in this embodiment is not limited to being a single member, and may be configured to be divided in the axial direction as the first internal gear 60A, the second internal gear 60B, and the third internal gear 60C.

[0047] The materials of the components that make up the planetary gear mechanism 52 are not particularly limited. As an example, the sun gear 54, planet carrier 58, and internal gear 60 are made of synthetic resin, and the planetary gear 56 is made of a hard material such as metal. In other words, the planetary gear 56 is made of a different material from the sun gear 54 and the internal gear 60. In this embodiment, the teeth of the planetary gear 56, the sun gear 54, and the internal gear 60 have a spur gear shape.

[0048] In this embodiment, the internal gear 60 is fixed to the valve body 14. Torque is input to the sun gear 54 from one axial side, and the planetary carrier 58, to which the planetary gears 56 are rotatably connected, outputs torque to the other axial side. In other words, the planetary gear mechanism 52 in this embodiment is a speed reduction mechanism.

[0049] The reduction gear device 50 functions as a reduction gear device by transmitting torque in this order from the first planetary gear mechanism 52A to the second planetary gear mechanism 52B and the third planetary gear mechanism 52C due to the rotation of the rotor 42 described above, and outputting the torque from the third planetary gear mechanism 52C. In other words, the planet carrier 58 in the third planetary gear mechanism 52C transmits the torque to the spindle 26 of the feed screw mechanism 24, and the reduction gear device 50 inputs the torque to the feed screw mechanism 24.

[0050] The internal gear 60 is restricted from rotating in the circumferential direction relative to the can 48 and the valve body 14. There are no particular limitations on the method for restricting this rotation, but in this embodiment, as an example, the other axial side of the internal gear 60 is joined to the can 48 and the valve body 14 by a joining material 49.

[0051] In this embodiment, the first sun gear 54A and the second sun gear 54B are similar in specifications such as axial length, module, and number of teeth. The first planetary gear 56A and the second planetary gear 56B are similar in specifications such as axial length, module, and fraction. The first internal gear 60A and the second internal gear 60B are similar in specifications such as axial length, module, and fraction. In other words, the specifications of the gears in the first planetary gear mechanism 52A and the second planetary gear mechanism 52B are similar.

[0052] 2, in this embodiment, the third sun gear 54C, the third satellite gears, and the third planetary carrier 58C are longer in the axial direction than the first sun gear 54A, the first satellite gears, and the first planetary carrier 58A. In other words, the face width of the gears in the third planetary gear mechanism 52C is larger than the face width of the gears in the first planetary gear mechanism 52A. Note that the specifications of the other gears are the same as those of the first planetary gear mechanism 52A and the second planetary gear mechanism 52B.

[0053] Next, the operation and effects of the motor-operated valve 10 according to this embodiment will be described.

[0054] (Action and effect) In a reduction gear 50 having multiple planetary gear mechanisms 52, such as the reduction gear 50 included in the motor-operated valve 10 according to this embodiment, the largest torque is applied to the sun gear 54 of the planetary gear mechanism 52 that outputs torque (i.e., the third sun gear 54C in this embodiment). When the torque applied to the gears is large, the pressure generated between the meshing gears tends to accelerate wear at the meshing portions of the gears. For this reason, in a motor-operated valve 10 having multiple planetary gear mechanisms 52, the gear of the planetary gear mechanism 52 closest to the feed screw mechanism 24 is more likely to be damaged.

[0055] The pressure applied to the third sun gear 54C is conceptually defined by the following formula: Pressure [Pa] = Torque output by third sun gear 54C [N m] ÷ (Pitch circle radius of third sun gear 54C [m] × Contact area between the tooth surfaces of third sun gear 54C and third planetary gear 56C [m 2 ])

[0056] In the third planetary gear mechanism 52C of this embodiment, the face widths of the third sun gear 54C, the third planetary gear 56C, and the third fixed gear are longer than the face widths of the first sun gear 54A, the first planetary gear 56A, and the first fixed gear. Therefore, compared to when the gears of the third planetary gear mechanism 52C have the same shape as the gears of the first planetary gear mechanism 52A, the contact area between the tooth surfaces of the third sun gear 54C and the third planetary gear 56C is larger, and the pressure (load per unit area) applied to the sun gear 54 of the third planetary gear mechanism 52C is reduced. In other words, the reduction means in this embodiment reduces the pressure applied to the surfaces of the gears of the third planetary gear mechanism 52C by increasing the face widths of the gears of the third planetary gear mechanism 52C.

[0057] Furthermore, with this motor-operated valve 10, compared to when the gears of the third planetary gear mechanism 52C have the same shape as the gears of the first planetary gear mechanism 52A, the pressure on the gears of the third planetary gear mechanism 52C is reduced, thereby suppressing damage to the third planetary gear mechanism 52C. In other words, with the motor-operated valve 10 according to this embodiment, the pressure on the gears of the third planetary gear mechanism 52C is reduced, thereby suppressing damage to the reduction gear device 50.

[0058] (Variation) In the present embodiment, an example has been described in which the face width of the gear in the third planetary gear mechanism 52C is longer than the face widths of the gears in the first planetary gear mechanism 52A and the second planetary gear mechanism 52B, but this is not limiting. For example, the face width of the gear in the second planetary gear mechanism 52B may be larger than the face width of the gear in the first planetary gear mechanism 52A. In this case, compared to when the gear of the second planetary gear mechanism 52B has the same shape as the gear of the first planetary gear mechanism 52A, the pressure on the gear of the second planetary gear mechanism 52B is lower, and therefore damage to the second planetary gear mechanism 52B is suppressed.

[0059] In the above description, the internal gear 60 of the planetary gear mechanism 52 is fixed, the sun gear 54 inputs torque, and the planet carrier 58 outputs torque, but this is not limited to this. For example, a reduction mechanism may be configured in which the sun gear 54 is fixed in the circumferential direction by the shaft 44, and the divided internal gears 60 are rotatable for each planetary gear mechanism 52. In this case, the planet carrier 58 is connected to the internal gear 60 on the other side in the axial direction, thereby configuring a reduction mechanism in which the internal gear 60 inputs torque and the planet carrier 58 outputs torque.

[0060] [Second embodiment] Next, a motor-operated valve 10 according to a second embodiment of the present disclosure will be described with appropriate reference to Fig. 3. In the motor-operated valve 10 according to the second embodiment, the same components as those in the motor-operated valve 10 according to the first embodiment will be denoted by the same reference numerals as those in the first embodiment, and descriptions thereof will be omitted.

[0061] (composition) As shown in FIG. 3 , in contrast to the motor-operated valve 10 according to the first embodiment, the third sun gear 154C according to this embodiment has the same number of teeth as the first sun gear 54A but a larger module than the first sun gear 54A. In other words, the third sun gear 154C has a larger diameter than the first sun gear 54A. Similarly, the third planetary gear 156C has the same number of teeth as the first planetary gear 56A but a larger module than the first planetary gear 56A, and the third internal gear 160C has the same number of teeth as the first internal gear 60A but a larger module than the first internal gear 60A. In addition, in accordance with the shape of the third sun gear 154C, the third planetary carrier 158C rotatably supports the third planetary gear 156C radially outward of the first planetary carrier 158A.

[0062] The other specifications of the gears in the third planetary gear mechanism 152C are the same as those of the first planetary gear mechanism 52A and the second planetary gear mechanism 52B. The other configurations are the same as those of the motor-operated valve 10 according to the first embodiment.

[0063] Next, the operation and effects of the motor-operated valve 10 according to this embodiment will be described.

[0064] (Action and effect) When the drive mechanism 33 is driven to adjust the opening amount of the opening 18, the valve disc 22 may hit the valve seat 20 or the speed at which the valve disc 22 moves back and forth may change suddenly, causing an impact on the adjustment mechanism 21. This impact is transmitted via the adjustment mechanism 21 to the gear of the planetary gear mechanism 152 that outputs torque in the reduction gear device 150. For this reason, in an electrically operated valve 10 having multiple planetary gear mechanisms 152, the gear of the planetary gear mechanism 152 closest to the feed screw mechanism 24 is more likely to be damaged.

[0065] In the third planetary gear mechanism 152C of this embodiment, the modules of the third sun gear 154C, the third planetary gear 156C, and the third fixed gear are larger than the modules of the first sun gear 54A, the first planetary gear 56A, and the first fixed gear. Therefore, compared to when the gears of the third planetary gear mechanism 152C have the same shape as the gears of the first planetary gear mechanism 52A, the tooth thickness of the gears of the third planetary gear mechanism 152C is larger, and the impact resistance of the third planetary gear mechanism 152C is improved. Furthermore, by increasing the gear modules, the contact areas of the tooth surfaces of the third sun gear 154C and the third planetary gear 156C are also increased. In other words, the reduction means of this embodiment reduces the pressure generated in the gears of the third planetary gear mechanism 152C by increasing the modules of the gears of the third planetary gear mechanism 152C.

[0066] Furthermore, with this motor-operated valve 10, the gears of the third planetary gear mechanism 152C have greater durability than when the gears have the same shape as the gears of the first planetary gear mechanism 52A, and therefore damage to the third planetary gear mechanism 152C is suppressed. In other words, with the motor-operated valve 10 according to this embodiment, pressure on the gears of the third planetary gear mechanism 152C is reduced, and therefore damage to the reduction gear device 150 is suppressed.

[0067] (Variation) In the present embodiment, the module of the gear in the third planetary gear mechanism 152C is larger than the modules of the gears in the first planetary gear mechanism 52A and the second planetary gear mechanism 52B, but this is not limited to this. For example, the module of the gear in the second planetary gear mechanism 52B may be larger than the module of the gear in the first planetary gear mechanism 52A. In this case, the pressure on the gear of the second planetary gear mechanism 52B is lower than when the gear of the second planetary gear mechanism 52B has the same shape as the gear of the first planetary gear mechanism 52A, and therefore damage to the second planetary gear mechanism 52B is suppressed.

[0068] [Third embodiment] Next, a motor-operated valve 10 according to a third embodiment of the present disclosure will be described with appropriate reference to Figure 4. In the motor-operated valve 10 according to the third embodiment, the same components as those in the motor-operated valve 10 according to the first embodiment will be denoted by the same reference numerals as those in the first embodiment, and descriptions thereof will be omitted.

[0069] (composition) As shown in FIG. 4 , in this embodiment, the second planetary carrier 58B is integrated with the third planetary carrier 258C on the other axial side, and the third sun gear 254C is engaged with the spindle 26 on the other axial side via protrusions and recesses (not shown). In other words, in the third planetary gear mechanism 252C of this embodiment, torque output from the second planetary gear mechanism 52B is input to the third planetary carrier 258C, and the third sun gear 254C outputs the torque to the other axial side. The third internal gear 260C is fixed, as are the first internal gear 60A and the second internal gear 60B. That is, in this embodiment, the third planetary gear mechanism 252C outputs torque. In other words, in the reduction gear transmission 250 of this embodiment, the first planetary gear mechanism 52A and the second planetary gear mechanism 52B function as reduction mechanisms, and the third planetary gear mechanism 252C functions as a speed-up mechanism. However, the reduction gear 50 is a device that reduces the speed so that the output rotation speed is lower than the input rotation speed as a whole.

[0070] The specifications of the other gears in the third planetary gear mechanism 252C are the same as those of the first planetary gear mechanism 52A and the second planetary gear mechanism 52B. The other configurations are the same as those of the motor-operated valve 10 according to the first embodiment.

[0071] Next, the operation and effects of the motor-operated valve 10 according to this embodiment will be described.

[0072] (Action and effect) As described above, in the motor-operated valve 10 having a plurality of planetary gear mechanisms 252, the gear of the planetary gear mechanism 252 closest to the feed screw mechanism 24 is more likely to be damaged.

[0073] In the third planetary gear mechanism 252C of this embodiment, the third planetary carrier 258C inputs torque and the third aspect gear outputs torque, so the third planetary gear mechanism 252C functions as a speed-increasing mechanism. In other words, in the motor-operated valve 10 of this embodiment, the torque applied to the gears is reduced compared to when the third planetary gear mechanism 252C is a speed-reducing mechanism like the first planetary gear mechanism 52A and the second planetary gear mechanism 52B. In other words, the reduction means of this embodiment reduces the pressure of the third planetary gear mechanism 252C by making the third planetary gear mechanism 252C a speed-increasing mechanism.

[0074] Furthermore, with this motor-operated valve 10, the torque associated with the gears of the third planetary gear mechanism 252C is reduced compared to when the gears of the third planetary gear mechanism 252C are a reduction mechanism similar to the gears of the first planetary gear mechanism 52A. In other words, with the motor-operated valve 10 according to this embodiment, the probability of damage to the planetary gear mechanism 252 is distributed between the third planetary gear mechanism 252C and the second planetary gear mechanism 52B. Therefore, with the motor-operated valve 10 according to this embodiment, damage to the third planetary gear mechanism 252C is suppressed compared to when the third planetary gear mechanism 252C is a planetary gear mechanism 52 similar to the first planetary gear mechanism 52A. In other words, with the motor-operated valve 10 according to this embodiment, damage to the reduction gear 250 is suppressed.

[0075] (Variation) In the above description, the first planetary gear mechanism 52A and the second planetary gear mechanism 52B are defined as reduction mechanisms, and the third planetary gear mechanism 252C is defined as a speed-increasing mechanism, but this is not limited to this. For example, if the reduction gear device 250 is a reduction mechanism as a whole, only the first planetary gear mechanism 52A may be defined as a reduction mechanism, and the second planetary gear mechanism 52B and the third planetary gear mechanism 252C may be defined as speed-increasing mechanisms.

[0076] (Other variations) In addition, in the above description, the reduction gear device 50 has three planetary gear mechanisms 52, but the number of planetary gear mechanisms 52 in the motor-operated valve 10 according to the present disclosure is not limited to this. The number of planetary gear mechanisms 52 may be four or more, or may be two.

[0077] Furthermore, in the above description, each planetary gear mechanism 52 of the reduction gear device 50 has three planetary gears 56, but the number of planetary gears 56 according to the present disclosure is not limited to this. For example, the third planetary gear mechanism 52C may have four or more third planetary gears 56C. In other words, by having more third planetary gears 56C than the first planetary gear mechanism 52A and the second planetary gear mechanism 52B, the pressure applied to the third sun gear 54C may be reduced.

[0078] In the above description, the gear specifications have been described as being limited to the face width and module, but in the present disclosure, the specifications that are made different in each planetary gear mechanism 52 are not limited to these as long as they increase the contact area between the gears. For example, helical gears with slanted teeth may be used to increase the contact area between the gears and reduce the pressure in the planetary gear mechanism 52.

[0079] The above describes an embodiment of the present disclosure with reference to the accompanying drawings. However, it is clear that a person with ordinary knowledge in the field of technology to which the present disclosure pertains can conceive of various modifications or applications within the scope of the technical ideas set forth in the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure. [Explanation of symbols]

[0080] 10 Motor-operated valve 11 Inlet 12 Outlet 14 Valve body 16 Valve chamber 18 Aperture 20 Valve seat 21 Adjustment mechanism 22 Valve body 23 Guide section 24 Lead screw mechanism 26 Spindle 28 Nut 30 Plunger 32 Coil spring 33 Drive mechanism 34 Motor 36 Stator 40 bobbins 41 Permanent magnets 42 rotor 44 shaft body 45 Shaft support member 46 Cover 48 Can 49 Binding material 50 Reducer 52 Planetary gear mechanism 54 Sun Gear 56 Planetary gear 58 Career 60 Internal gear

Claims

1. a valve body having a valve chamber and a valve seat; a can having a cylindrical shape extending in an axial direction and disposed on one side of the valve body in the axial direction; a valve body disposed in the valve chamber; a feed screw mechanism that moves the valve element forward and backward in the axial direction relative to the valve seat; a rotor rotatably supported on the inner periphery of the can; a reduction gear device having three 2K-H type planetary gear mechanisms arranged side by side in the axial direction, which transmits torque to the three planetary gear mechanisms in order from the side farthest from the feed screw mechanism to the side closest to the feed screw mechanism, thereby reducing the rotational speed of the rotor and transmitting the torque to the feed screw mechanism; a reduction means for reducing the pressure acting on a gear of the planetary gear mechanism that is located closest to the feed screw mechanism among the three planetary gear mechanisms; An electrically operated valve.

2. The reduction means is configured such that the planetary gear mechanism located farthest from the feed screw mechanism and the planetary gear mechanism located closest to the feed screw mechanism have different gear specifications. The electrically operated valve according to claim 1 .

3. In the three planetary gear mechanisms, torque is input to the sun gear and torque is output from the planetary carrier, Among the planetary gear mechanisms adjacent to each other in the axial direction, one planetary gear mechanism located closer to the feed screw mechanism has larger face widths of a sun gear and a planet gear than the other planetary gear mechanism located farther from the feed screw mechanism. The motor-operated valve according to claim 2.

4. the planetary gear mechanism arranged closest to the feed screw mechanism has a larger face width between the sun gear and the planet gear than the planetary gear mechanism arranged farthest from the feed screw mechanism; The motor-operated valve according to claim 2.

5. In the three planetary gear mechanisms, torque is input to the sun gear and torque is output from the planetary carrier, Among the planetary gear mechanisms adjacent to each other in the axial direction, one planetary gear mechanism disposed closer to the feed screw mechanism has a larger module than the other planetary gear mechanism disposed farther from the feed screw mechanism. The motor-operated valve according to claim 2.

6. the planetary gear mechanism arranged closest to the feed screw mechanism has a larger module than the planetary gear mechanism arranged farthest from the feed screw mechanism; The motor-operated valve according to claim 2.

7. The reduction means is configured such that a planetary gear mechanism arranged closest to the feed screw mechanism inputs torque through a planet carrier and outputs torque through a sun gear. The electrically operated valve according to claim 1 .

8. a stator disposed on the outer periphery of the can and configured to rotate the rotor; The motor-operated valve according to any one of claims 1 to 7.

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