Solenoid switching valve

Abstract

The present invention seeks to simplify and facilitate the assembly of an electromagnetic switching valve. The electromagnetic switching valve comprises: a sleeve defining a port connected to an oil circuit; a spool disposed within the sleeve so as to freely reciprocate along a predetermined axis to open and close the port; an electromagnetic actuator comprising a plunger disposed on the axis and a stator for applying a magnetomotive force to the plunger; and a cylindrical transmission member disposed on the axis so as to be interposed between the plunger and the spool to transmit a driving force. The transmission member includes a restricted portion. When the transmission member is vertically lowered into the sleeve for assembly so that its lower end abuts the spool mounted in the sleeve, the restricted portion is restrained so that the upper end of the transmission member does not escape from a range within which the stator can be inserted.

Description

Technical Field

[0001] The present invention relates to an electromagnetic switching valve that switches the oil path of hydraulic oil by operating a spool through an electromagnetic actuator. In particular, the present invention relates to an electromagnetic switching valve used in a valve timing changing device that changes the opening and closing period (valve timing) of an intake valve or an exhaust valve in an internal combustion engine mounted on a vehicle such as an automobile or a two-wheeled vehicle. Background Art

[0002] As a conventional electromagnetic switching valve, an electromagnetic spool valve is known, which includes: a spool valve having a sleeve, a spool slidably arranged in the sleeve, and a return spring for returning the spool to a rest position; an electromagnetic actuator having a coil, a plunger, and a stator; and a cylindrical shaft as a transmission member, which is interposed between the plunger and the spool to transmit a driving force (for example, refer to Patent Document 1).

[0003] When assembling the electromagnetic slide valve, the following process can be considered: prepare a slide valve with a return spring and a slide column pre-installed in the sleeve, a shaft, and an electromagnetic actuator with a plunger and a stator pre-installed, and then assemble them by connecting them by clamping the shaft between the slide valve and the electromagnetic actuator.

[0004] Here, as an assembly method, the opening of the sleeve is directed upward in the vertical direction and the sleeve is fixed to prevent the slide post and the like from falling off. Then, the shaft is dropped from above in a manner abutting the slide post, and the electromagnetic actuator is approached from above the shaft for connection. In the above case, if the shaft is tilted relative to the vertical direction, the plunger of the electromagnetic actuator cannot be accurately connected to the shaft.

[0005] In order to cope with the above situation, the electromagnetic actuator needs to be assembled while the shaft is held upright using a jig or the like, which makes the assembly work complicated.

[0006] As another assembly method, the electromagnetic actuator is fixed with its opening facing vertically upward, and then the shaft is dropped in from above so as to abut against the plunger, and the sliding valve is brought close to the shaft from above for connection. In this case, a clamp or the like is required to hold it in place to prevent the sliding post in the sleeve from falling off. As described above, the assembly operation is complicated.

[0007] [Prior art literature]

[0008] [Patent Document]

[0009] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-63022 Summary of the Invention

[0010] [Problems to be solved by the invention]

[0011] The present invention has been completed in view of the above situation, and its purpose is to provide an electromagnetic switching valve that can simplify and facilitate the assembly work when assembling the electromagnetic switching valve, and can easily assemble the transmission component that transmits the driving force of the plunger to the slide.

[0012] [Technical means to solve the problem]

[0013] The electromagnetic switching valve of the present invention includes: a sleeve, which defines a port connected to an oil circuit, and the oil circuit supplies or discharges working oil; a slide rod, which is configured in the sleeve to move back and forth freely on a specified axis to open and close the port; an electromagnetic actuator, which includes a plunger configured on the axis and a stator that applies magnetic flux potential to the plunger; and a cylindrical transmission member, which is configured on the axis so as to be interposed between the plunger and the slide rod to transmit driving force. The electromagnetic switching valve is constructed as follows: the stator includes a through hole for inserting the transmission member, and the transmission member includes a restricted portion. When the transmission member falls into the sleeve from a vertical direction for assembly so that the lower end of the transmission member abuts against the slide rod installed in the sleeve, the restricted portion is restricted so that the upper end of the transmission member does not deviate from the range that can be inserted into the through hole of the stator.

[0014] In the electromagnetic switching valve, a configuration may be adopted in which the restricted portion includes a protrusion that protrudes from the outer peripheral surface of the transmission member so as to contact the inner peripheral surface of the sleeve and thereby be restricted.

[0015] In the electromagnetic switching valve, a configuration may be adopted in which the protruding portion includes a plurality of protruding ribs, and the plurality of protruding ribs are discretely arranged in the circumferential direction on the outer peripheral surface of the transmission member.

[0016] In the electromagnetic switching valve, a configuration may be adopted in which the stator includes a guide portion around the insertion hole, and the guide portion guides the upper end portion of the transmission member toward the axis.

[0017] In the electromagnetic switching valve, a configuration may be adopted in which the guide portion is formed as a concave tapered surface or a concave curved surface centered on the axis.

[0018] In the electromagnetic switching valve, the transmission member may have a lower end formed into a concave tapered surface, and the spool may include an end formed into a convex curved surface for contacting the lower end of the transmission member.

[0019] In the electromagnetic switching valve, the upper end portion of the transmission member may be formed into a convex curved surface, and the plunger may include an accommodating recessed portion formed into a concave tapered surface so as to abut against the upper end portion of the transmission member.

[0020] In the electromagnetic switching valve, the inner diameter of the insertion hole of the stator may be formed to restrict the transmission member so that the upper end portion of the transmission member does not fall out of the range in which the upper end portion of the transmission member can be inserted into the accommodating recess of the plunger.

[0021] In the electromagnetic switching valve, the transmission member may include a large-diameter cylindrical portion disposed in the sleeve and a small-diameter cylindrical portion inserted into the insertion hole of the stator, wherein the large-diameter cylindrical portion includes the restricted portion.

[0022] In the electromagnetic switching valve, a configuration may be adopted in which the restricted portion includes a protrusion that protrudes from the outer peripheral surface of the large-diameter cylindrical portion so as to contact the inner peripheral surface of the sleeve to be restricted.

[0023] In the electromagnetic switching valve, a configuration may be adopted in which the protruding portion includes a plurality of protruding ribs, and the plurality of protruding ribs are discretely arranged in the circumferential direction on the outer peripheral surface of the large-diameter cylindrical portion.

[0024] In the electromagnetic switching valve, the transmission member may include a thinned portion formed between the plurality of protruding ribs so as to be recessed radially inward from the outer peripheral surface of the large-diameter cylindrical portion.

[0025] In the electromagnetic switching valve, a configuration may be adopted in which the transmission member is formed of a resin material.

[0026] [Effects of the Invention]

[0027] According to the electromagnetic switching valve having the above-described structure, when assembling the electromagnetic switching valve, the assembly work can be simplified and facilitated, and the transmission member that transmits the driving force of the plunger to the spool can be easily assembled. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a structural diagram of a case where the electromagnetic switching valve of the present invention is applied to a valve timing changing device of an internal combustion engine.

[0029] Figure 2 This is an exploded perspective view of the electromagnetic switching valve according to one embodiment of the present invention as viewed from the sleeve side.

[0030] Figure 3 This is an exploded perspective view of the electromagnetic switching valve according to one embodiment of the present invention, viewed from the electromagnetic actuator side.

[0031] Figure 4 This is an exploded perspective view of an electromagnetic actuator included in an electromagnetic switching valve according to one embodiment.

[0032] Figure 5This is an external perspective view showing the relationship between a transmission member and an inner wall surface of a sleeve included in an electromagnetic switching valve according to one embodiment.

[0033] Figure 6 This is a cross-sectional view of a transmission member included in an electromagnetic switching valve according to an embodiment.

[0034] Figure 7 This is a schematic diagram showing the relationship among a transmission member, an inner wall surface of a sleeve, an insertion hole of a stator, and an accommodating recess of a plunger included in an electromagnetic switching valve according to one embodiment.

[0035] Figure 8 This is a cross-sectional view illustrating assembly of a transmission member in an electromagnetic switching valve according to an embodiment.

[0036] Figure 9 This is a cross-sectional view illustrating assembly of a transmission member in an electromagnetic switching valve according to an embodiment.

[0037] Figure 10 This is a cross-sectional view illustrating assembly of a transmission member in an electromagnetic switching valve according to an embodiment.

[0038] Figure 11 The operation of the electromagnetic switching valve according to one embodiment will be described, and a cross-sectional view is provided showing a state where the spool and the plunger are located at the rest position.

[0039] Figure 12 The operation of the electromagnetic switching valve according to one embodiment will be described, and a cross-sectional view is provided showing a state in which the spool and the plunger have moved forward and are located at the maximum movement position.

[0040] [Explanation of Symbols]

[0041] S: axis

[0042] 3: Oil supply circuit

[0043] 4: Discharge oil circuit

[0044] 5: First oil circuit

[0045] 6: Second oil circuit

[0046] V: Solenoid switching valve

[0047] 10: Sleeve

[0048] 11b: Supply port

[0049] 11c, 11d: Exhaust port

[0050] 11e: First port

[0051] 11f: Second port

[0052] 13: Inner circumference

[0053] 20: Sliding column

[0054] 27: Second end (end, convex curved surface)

[0055] 60: Transfer component

[0056] 61: Small diameter tube

[0057] 61a: End (upper end, convex curved surface)

[0058] 62: Large diameter barrel

[0059] 62s: outer surface

[0060] 62c: Thinning part

[0061] 62d: Annular contact portion (lower end, concave tapered surface)

[0062] 62e: protruding rib (protruding portion, restricted portion)

[0063] A: Electromagnetic actuator

[0064] 70: Plunger

[0065] 75: Accommodating concave portion (concave tapered surface)

[0066] 90: stator

[0067] 91a: Through hole

[0068] 91d: Guide portion (concave tapered surface or concave curved surface) DETAILED DESCRIPTION

[0069] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0070] like Figure 1 As shown, an electromagnetic switching valve V according to one embodiment of the present invention is applied to a valve timing changing device M of an internal combustion engine.

[0071] The electromagnetic switching valve V is appropriately driven and controlled by the control unit ECU according to the operating conditions of the vehicle and the internal combustion engine.

[0072] The engine body EB includes: a fitting hole H for inserting the electromagnetic switching valve V; a supply oil passage 3 for supplying the working oil in the oil pan 1 via the oil pump 2; a discharge oil passage 4 for discharging the working oil from the electromagnetic switching valve V to the oil pan 1; a first oil passage 5 connected to one of the retarded angle chamber RC and the advanced angle chamber AC of the valve timing changing device M; and a second oil passage 6 connected to the other of the retarded angle chamber RC and the advanced angle chamber AC of the valve timing changing device M.

[0073] The valve timing varying device M includes a vane rotor 7 that rotates integrally with the camshaft CS, and a housing rotor 8 that accommodates the vane rotor 7 so as to be relatively rotatable within a predetermined angular range and rotates in conjunction with the crankshaft.

[0074] Furthermore, an advance angle chamber AC and a retard angle chamber RC, through which the hydraulic oil is supplied and discharged, are defined by the internal space of the housing rotor 8 and the vane rotor 7 .

[0075] Here, when the valve timing changing device M is applied to the intake-side camshaft CS, the first oil passage 5 is connected to the advanced angle chamber AC, and the second oil passage 6 is connected to the retarded angle chamber RC.

[0076] On the other hand, when the valve timing changing device M is applied to the exhaust-side camshaft CS, the first oil passage 5 is connected to the retardation chamber RC, and the second oil passage 6 is connected to the advancement chamber AC.

[0077] like Figure 2 and Figure 3 As shown, the electromagnetic switching valve V includes a sleeve 10 , a spool 20 , a biasing spring 30 , a sealing member 40 , a sealing member 50 , a transmission member 60 , and an electromagnetic actuator A.

[0078] like Figure 4 、 Figure 11 、 Figure 12 As shown, the electromagnetic actuator A includes a plunger 70 , a guide sleeve 80 , a stator 90 , a sealing member 100 , a bracket 110 , an inner yoke 120 , a molding unit 130 , a sealing member 140 , and an outer yoke 150 .

[0079] The sleeve 10 is formed of a metal material such as aluminum into a cylindrical shape centered on the axis S. Figure 2 、 Figure 3 、 Figure 11 As shown, it includes an outer peripheral surface 11, a sealing groove 11a, a supply port 11b, a discharge port 11c, a discharge port 11d, a first port 11e, a second port 11f, a connecting passage 11g, a connecting passage 11h, a connecting passage 11i, an inner peripheral surface 12, an inner peripheral surface 13, a receiving portion 14, and a flange portion 15.

[0080] The outer peripheral surface 11 is formed as a cylindrical surface centered on the axis S, and is fitted into the fitting hole H of the engine body EB.

[0081] The seal groove 11 a is formed as an annular groove on the outer peripheral surface 11 , and the seal member 40 is fitted therein.

[0082] The supply port 11 b communicates with the supply oil passage 3 . The discharge port 11 c and the discharge port 11 d communicate with the discharge oil passage 4 . The first port 11 e communicates with the first oil passage 5 . The second port 11 f communicates with the second oil passage 6 .

[0083] The communication passage 11 g is formed at the end of the sleeve 10 , and allows the space where the biasing spring 30 is arranged to communicate with the discharge oil passage 4 .

[0084] The communication passage 11 h opens in the radial direction near the end portion of the sleeve 10 , and allows the space where the biasing spring 30 is arranged to communicate with the discharge oil passage 4 .

[0085] The communication passage 11 i allows the internal space SS in which the transmission member 60 is arranged to communicate with the discharge oil passage 4 in a region of the inner peripheral surface 13 of the sleeve 10 .

[0086] The inner peripheral surface 12 is formed as a cylindrical surface centered on the axis S, and is brought into close contact with the outer peripheral surface 21 of the spool 20 so as to slidably guide the spool 20 .

[0087] The inner peripheral surface 13 is formed as a conical surface centered on the axis S, having an inner diameter larger than that of the inner peripheral surface 12 and gradually widening toward the flange portion 15 . The inner surface 13 is formed to ensure an internal space SS around the transmission member 60 when the transmission member 60 is arranged.

[0088] The receiving portion 14 receives the first end portion 26 of the spool 20 to stop the spool 20 at the maximum forward position, and also receives one end portion of the biasing spring 30 .

[0089] The flange 15 is joined to the stator 90 and the ends of the outer yoke 150 are riveted, thereby securing the flange 15 to the electromagnetic actuator A. Furthermore, the flange 15 is provided with an annular recess 15 a that cooperates with the stator 90 to accommodate the sealing member 50 while sandwiching the sealing member 50 .

[0090] like Figure 2 、 Figure 3 、 Figure 11 As shown, the spool 20 is formed to be elongated along the axis S direction and includes an outer peripheral surface 21 , a first valve portion 22 , a second valve portion 23 , a recess 24 , a receiving portion 25 , a first end portion 26 , and a second end portion 27 .

[0091] The outer peripheral surface 21 is formed in a cylindrical shape centered on the axis S and has an outer diameter that is substantially the same as or slightly smaller than the inner diameter of the inner peripheral surface 12 so as to slide on the inner peripheral surface 12 of the sleeve 10 .

[0092] The first valve portion 22 is formed to define an outer peripheral surface 21 wider than the opening width of the first port 11 e in the axis S direction, and opens and closes the first port 11 e of the sleeve 10 by moving in the axis S direction.

[0093] The second valve portion 23 is formed to define an outer peripheral surface 21 wider than the opening width of the second port 11 f in the axis S direction, and opens and closes the second port 11 f of the sleeve 10 by moving in the axis S direction.

[0094] The recessed portion 24 is formed on one side of the first end portion 26 so as to accommodate the biasing spring 30 in a telescopic manner.

[0095] A receiving portion 25 is formed as a bottom wall of the recessed portion 24 so as to receive the other end portion of the biasing spring 30 accommodated in the recessed portion 24 .

[0096] The first end portion 26 is formed as an annular end surface and is detachably abutted against the receiving portion 14 of the sleeve 10 .

[0097] The second end portion 27 is formed into a circular ring centered on the axis S and has a convex curved surface so as to abut against the annular abutment portion 62 d , which is the lower end portion of the transmission member 60 , in the axis S direction.

[0098] The biasing spring 30 is a compression type coil spring, and is assembled so that one end thereof abuts against the receiving portion 14 of the sleeve 10 and the other end thereof abuts against the receiving portion 25 of the spool 20 .

[0099] Moreover, when in the rest state, the force spring 30 applies the following force: Figure 11 As shown, the plunger 70 is retracted to the rest position, and the spool 20 is stopped at a position where the first valve portion 22 blocks the communication between the first port 11e and the supply port 11b and connects the first port 11e with the discharge port 11c, and the second valve portion 23 connects the second port 11f with the supply port 11b and blocks the communication between the second port 11f and the discharge port 11d.

[0100] The sealing member 40 is an O-ring made of rubber, and is fitted into the seal groove 11 a of the sleeve 10 to seal between the engine body EB and the sleeve 10 .

[0101] The sealing member 50 is an O-ring made of rubber, and is disposed in the annular recess 15 a of the flange portion 15 of the sleeve 10 to seal between the sleeve 10 and the stator 90 .

[0102] The transmission member 60 is formed of a resin material into a cylindrical shape extending in the direction of the axis S so as to be interposed between the plunger 70 and the spool 20 to transmit the driving force. Figures 5 to 7 As shown, the transmission member 60 includes a small diameter cylindrical portion 61 inserted into the insertion hole 91 a of the stator 90 , a large diameter cylindrical portion 62 arranged in the region of the inner peripheral surface 13 in the sleeve 10 , and an annular step portion 63 .

[0103] The small-diameter cylindrical portion 61 includes an end portion 61 a serving as an upper end portion, a facing wall 61 b ​​, a first internal passage 61 c , two first openings 61 d , a second internal passage 61 e , and two second openings 61 f .

[0104] The end portion 61 a is formed in an annular shape centered on the axis S and has a convex curved surface, and abuts against the accommodating recess 75 of the plunger 70 .

[0105] The facing wall 61 b ​​is formed as a blocking wall that faces the through-passage 74 of the plunger 70 in the axis S direction.

[0106] The first internal passage 61c is formed closer to the plunger 70 than the facing wall 61b in the direction of the axis S, and is formed as a cylindrical hole extending in the direction of the axis S so as to communicate with the through-passage 74 of the plunger 70. The passage area of ​​the first internal passage 61c is formed to be equal to or larger than the passage area of ​​the through-passage 74. Here, the passage area of ​​the first internal passage 61c refers to the passage area of ​​the first internal passage 61c in a cross-section perpendicular to the axis S, and the passage area of ​​the through-passage 74 refers to the passage area of ​​the through-passage 74 in a cross-section perpendicular to the axis S.

[0107] like Figure 11 and Figure 12 As shown, the first opening 61d is formed closer to the plunger 70 than the insertion hole 91a of the stator 90 in the direction of the axis S, and is formed as a circular hole that opens the first internal passage 61c in the radial direction. The passage area of ​​the first opening 61d is equal to or larger than the passage area of ​​the first internal passage 61c. Here, the passage area of ​​the first opening 61d refers to the passage area of ​​the two first openings 61d formed as circular holes.

[0108] The second internal passage 61e is formed closer to the spool 20 than the facing wall 61b in the direction of the axis S and is formed as a cylindrical hole extending in the direction of the axis S. The inner diameter (passage area) of the second internal passage 61e is formed to be larger than the inner diameter (passage area) of the first internal passage 61c.

[0109] like Figure 11 and Figure 12 As shown, the second opening 61f is formed closer to the spool 20 than the insertion hole 91a of the stator 90 in the direction of the axis S. It is formed as a circular hole that opens the second internal passage 61e in the radial direction. The passage area of ​​the second opening 61f is equal to or larger than the passage area of ​​the second internal passage 61e. Here, the passage area of ​​the second opening 61f refers to the passage area of ​​the two second openings 61f formed as circular holes, and the passage area of ​​the second internal passage 61e refers to the passage area of ​​the second internal passage 61e in a cross-section perpendicular to the axis S.

[0110] The large diameter cylindrical portion 62 includes an outer peripheral surface 62s, a second internal passage 62a, four second openings 62b, four thinning portions 62c formed around the second openings 62b, an annular abutment portion 62d as a lower end portion, and four protruding ribs 62e as restricted portions and protruding portions.

[0111] The second internal passage 62a is formed closer to the spool 20 than the facing wall 61b in the direction of the axis S and is formed as a cylindrical hole extending in the direction of the axis S so as to communicate with the second internal passage 61e. The inner diameter (passage area) of the second internal passage 62a is larger than the inner diameter (passage area) of the second internal passage 61e.

[0112] like Figure 11 and Figure 12 As shown, the second openings 62b are formed closer to the spool 20 than the insertion holes 91a of the stator 90 in the direction of the axis S. They are formed as generally rectangular holes that radially open the second internal passage 62a. The passage area of ​​the second openings 62b is equal to or larger than the passage area of ​​the second internal passage 62a. Here, the passage area of ​​the second openings 62b refers to the passage area of ​​the four second openings 62b formed as generally rectangular holes, while the passage area of ​​the second internal passage 62a refers to the passage area of ​​the second internal passage 62a in a cross-section perpendicular to the axis S.

[0113] The four thinned portions 62c are formed in such a manner that the area around the second opening 62b is recessed radially inward from the outer peripheral surface 62s of the large-diameter cylindrical portion 62. Figure 5 As shown, when the transmission member 60 is arranged in the sleeve 10 , a sufficient gap space for the flow of the operating oil can be ensured between the transmission member 60 and the inner peripheral surface 13 .

[0114] The annular contact portion 62 d is formed into a concave tapered surface in an annular shape centered on the axis S to define an end portion of the second internal passage 62 a opening toward the spool 20 and to contact the second end portion 27 of the spool 20 .

[0115] like Figure 5 and Figure 6 As shown, four protruding ribs 62e are formed to protrude radially outward from the outer peripheral surface 62s of the large-diameter cylindrical portion 62 and are discretely arranged in the circumferential direction (here, at equal intervals in the circumferential direction).

[0116] Moreover, if Figure 7As shown, the four protruding ribs 62e function as restricted portions. When the transmission member 60 is dropped into the sleeve 10 from the vertical direction Vd for assembly so that the lower end portion of the transmission member 60, namely the annular abutting portion 62d, abuts against the sliding column 20 installed in the sleeve 10, the restricted portion is restricted so that the upper end portion of the transmission member 60, namely the end portion 61a, will not be out of the range of the insertion hole 91a that can be inserted into the stator 90.

[0117] The annular step portion 63 is formed at the boundary between the small-diameter cylindrical portion 61 and the large-diameter cylindrical portion 62 , and faces the annular facing portion 91 e of the stator 90 in the axis S direction.

[0118] The plunger 70 is formed of a ferromagnetic material such as iron and is cylindrical and elongated in the direction of the axis S. Figure 4 and Figure 11 As shown, it includes an outer peripheral surface 71 , a first end portion 72 , a second end portion 73 , a through passage 74 , and an accommodating recess 75 .

[0119] The outer peripheral surface 71 is slidably guided along the axis S direction by the inner wall surface 81 of the guide sleeve 80 .

[0120] The first end portion 72 is formed as an annular flat surface perpendicular to the axis S.

[0121] The second end portion 73 is formed as an annular flat surface perpendicular to the axis S, and abuts against the stopper 83 of the guide sleeve 80 at the rest position.

[0122] The through-passage 74 is arranged on the axis S and is elongated in the direction of the axis S to be formed as a cylindrical hole that penetrates from the first end portion 72 to the second end portion 73 .

[0123] The accommodating recess 75 is formed in an annular shape around the through-passage 74 of the first end portion 72 and has a concave tapered surface centered on the axis S so as to accommodate and abut the end portion 61 a of the transmission member 60 .

[0124] The guide sleeve 80 is formed by deep drawing a thin metal plate into a bottomed cylindrical shape centered on the axis S. Figure 4 and Figure 11 As shown, it includes an inner wall surface 81 , a bottom wall surface 82 , a stopper 83 protruding from the bottom wall surface 82 , and a flange portion 84 .

[0125] The inner wall surface 81 guides the plunger 70 so as to be slidable along the axis S direction.

[0126] The stopper 83 is formed to protrude inward from the bottom wall surface 82 in the axis S direction, and plays a role in defining the rest position of the plunger 70 .

[0127] Since the stopper 83 is formed to protrude inward, a gap is defined between the second end portion 73 of the plunger 70 and the bottom wall 82 when the plunger 70 abuts against the stopper 83. This prevents the plunger 70 from being in close contact with the bottom wall 82 of the guide sleeve 80 and becoming inoperable.

[0128] The flange portion 84 includes a region formed in a multi-step conical shape in the radial direction so as to cover the transmission member 60 from the outside, and is sandwiched and fixed between the stator 90 and the bracket 110 together with the sealing member 100 .

[0129] In the relationship between the guide sleeve 80 and the plunger 70, when the plunger 70 is located in the forward position in the direction of compressing the urging spring 30, as shown in FIG. Figure 12 As shown, a retreat space RS in which the plunger 70 can retreat to the rest position is defined by the inner wall surface 81 and the bottom wall surface 82 of the guide sleeve 80 and the second end portion 73 of the plunger 70 .

[0130] The stator 90 is formed using a ferromagnetic material and is fixed integrally by riveting a front end yoke 91 formed in a multi-stage cylindrical shape and an end yoke 92 formed in a roughly disc shape so as to form a part of the magnetic circuit and apply a magnetomotive force to the plunger 70 by energizing the coil 132.

[0131] like Figure 4 and Figure 11 As shown, the stator 90 includes an insertion hole 91a, an annular facing surface 91b, an annular inner wall surface 91c, a guide portion 91d, an annular facing portion 91e, a joint surface 92a, and a joint surface 92b.

[0132] The insertion hole 91 a is formed as a cylindrical hole centered on the axis S so that the small-diameter cylindrical portion 61 of the transmission member 60 can be inserted therethrough with a predetermined gap G therebetween.

[0133] The passage area of ​​the gap G defined around the transmission member 60 in the insertion hole 91a is smaller than the passage area of ​​the first opening 61d. The passage area of ​​the gap G refers to the passage area of ​​the gap G formed in an annular shape in a cross section perpendicular to the axis S.

[0134] Furthermore, it is preferable to make the gap G as small as possible within a range in which the viscous resistance of the hydraulic oil does not increase.

[0135] The annular facing surface 91 b is formed as an annular flat surface so as to face the first end portion 72 of the plunger 70 in the axis S direction.

[0136] The inner diameter of the insertion hole 91 a is formed so as to restrict the transmission member 60 so that the end portion 61 a of the transmission member 60 does not escape from the range in which the transmission member 60 can be inserted into the accommodation recess 75 of the plunger 70 .

[0137] The annular inner wall surface 91 c is formed as a substantially cylindrical surface centered on the axis S so as to face the outer peripheral surface 71 of the plunger 70 with a predetermined gap in the radial direction when the plunger 70 moves forward.

[0138] The guide portion 91d is formed in an annular shape centered on the axis S and has a concave tapered surface. When the transmission member 60 is inserted into the insertion hole 91a of the stator 90, the guide portion 91d serves to guide the end portion 61a of the transmission member 60 toward the axis S. Alternatively, the guide portion 91d may be formed in an annular shape centered on the axis S and have a concave curved surface.

[0139] The annular facing portion 91 e is formed in an annular shape centered on the axis S so as to face the annular step portion 63 of the transmission member 60 in the axis S direction.

[0140] The joint surfaces 92 a and 92 b are in close contact with the sealing members 50 and 100 in the assembled state and are formed as flat surfaces so as to be clamped and fixed to the flange portion 15 of the sleeve 10 and the bracket 110 .

[0141] In the relationship between the stator 90 and the plunger 70, when the plunger 70 is in the rest position, as shown in FIG. Figure 11 As shown, the annular facing surface 91 b and the annular inner wall surface 91 c of the stator 90 and the first end portion 72 of the plunger 70 define a forward movement space FS in which the plunger 70 can move forward in the direction of compressing the biasing spring 30 .

[0142] The sealing member 100 is a rubber O-ring, and is disposed between the joining surface 92 b of the stator 90 and the flange portion 84 of the guide sleeve 80 , thereby sealing the joining region between the stator 90 and the guide sleeve 80 .

[0143] The bracket 110 is formed of a metal material and includes an annular portion 111 and a mounting portion 112 .

[0144] The annular portion 111 is sandwiched between the mold unit 130 and the stator 90 (end yoke 92 ), and is fitted into the fitting recess 152 of the outer yoke 150 to be fixed.

[0145] The mounting portion 112 extends outward from the outer yoke 150 and is fixed to the engine body EB with screws or the like.

[0146] The inner yoke 120 forms a part of the magnetic circuit and is formed of a ferromagnetic material into a cylindrical shape with a flange and a bottom. Figure 4 and Figure 11 As shown, it includes a cylindrical portion 121 and a flange portion 122 .

[0147] The cylindrical portion 121 is formed so that the guide sleeve 80 is inserted into the inner side thereof and a bobbin 131 of the molding unit 130 is inserted into the outer side thereof.

[0148] The flange portion 122 is fitted into the fitting recess 153 of the outer yoke 150 and fixed by caulking.

[0149] like Figure 4 and Figure 11 As shown, the mold unit 130 includes: a resin bobbin 131 embedded in the cylindrical portion 121 of the inner yoke 120; a coil 132 for excitation wound around the bobbin 131; and a connector 133 integrally formed with the cylindrical portion covering the circumference of the coil 132 to surround the terminal.

[0150] The sealing member 140 is a rubber O-ring, and is disposed between the flange portion 122 of the inner yoke 120 and the bobbin 131 of the mold unit 130 to seal the space between the bobbin 131 and the inner yoke 120 .

[0151] The outer yoke 150 forms a part of the magnetic circuit and is formed into a cylindrical shape using a ferromagnetic material. Figure 4 and Figure 11 As shown, it includes a cylindrical part 151, a fitting recessed part 152, and a fitting recessed part 153.

[0152] The cylindrical portion 151 is formed into a cylindrical shape centered on the axis S, and is formed in a manner that covers the area of ​​the mold unit 130 where the coil 132 is wound, the flange portion 122 of the inner magnetic yoke 120, the annular portion 111 of the bracket 110, the stator 90 (end magnetic yoke 92), and the flange portion 15 of the sleeve 10 from the radial outside.

[0153] The fitting recess 152 is in a state where the annular portion 111 of the bracket 110, the stator 90 (end magnetic yoke 92), and the flange portion 15 of the sleeve 10 are embedded along the axis S direction, and the front end side area is riveted, thereby fixing the annular portion 111, the stator 90 (end magnetic yoke 92) and the flange portion 15.

[0154] The fitting recess 153 is fixed with the flange 122 of the inner yoke 120 fitted therein by crimping the distal end region.

[0155] Next, refer to Figures 8 to 10 The assembly operation of the electromagnetic switching valve V will be described.

[0156] First, if Figure 8 As shown, the sleeve 10 in which the sealing member 40 is incorporated, the biasing spring 30 , the spool 20 , the sealing member 50 , the transmission member 60 , and the electromagnetic actuator A are prepared.

[0157] Here, the electromagnetic actuator A is prepared as Figure 8 As shown, relative to the outer magnetic yoke 150 in which the flange portion 122 of the inner magnetic yoke 120 is embedded in the interlocking recess 153 and riveted, the sealing component 140, the molding unit 130, the bracket 110, the guide sleeve 80, the plunger 70, the sealing component 100 and the stator 90 are installed, and when the interlocking recess 152 is not riveted, the stator 90 and the like are held so as not to fall off by the electromagnetic attraction generated by energizing the coil 132.

[0158] Next, the sleeve 10 is oriented in the vertical direction Vd and fixed with a designated jig, and the biasing spring 30 and the spool 20 are assembled into the sleeve 10. Furthermore, the sealing member 50 is disposed in the annular recess 15a of the sleeve 10. Alternatively, the sleeve 10 may be erected in the vertical direction Vd after the biasing spring 30 and the spool 20 are pre-installed.

[0159] Next, the transmission member 60 is disposed above the spool 20 with the annular contact portion 62 d , which is the lower end portion, facing downward.

[0160] The electromagnetic actuator A held by energization is arranged above the transmission member 60 with the insertion hole 91a of the stator 90 facing downward. Alternatively, the electromagnetic actuator A may be arranged after the transmission member 60 is lowered.

[0161] Then, the transmission member 60 is dropped from the vertical direction Vd so that the lower end portion of the transmission member 60 , that is, the annular contact portion 62 d , contacts the spool 20 .

[0162] In the falling operation, usually Figure 9 As shown, the transmission member 60 abuts against the spool 20 in a state of being offset from the axis S and tilted.

[0163] Here, a part of the plurality of protruding ribs 62e as the restricted portion of the transmission member 60 is as shown in FIG. Figure 9 As shown, the transmission member 60 contacts the inner peripheral surface 13 of the sleeve 10 , thereby restricting the inclination of the transmission member 60 .

[0164] In the restricted state, the protruding rib 62e contacts the inner peripheral surface 13 of the sleeve 10, so that Figure 7 As shown, the end portion 61 a , which is the upper end portion of the transmission member 60 , is restricted so as not to be removed from a range in which the transmission member 60 can be inserted into the insertion hole 91 a of the stator 90 disposed upward in the vertical direction Vd.

[0165] In addition, during the falling operation, when the annular abutment portion 62d of the transmission member 60 adapts to the second end portion 27 of the sliding column 20, that is, when the concave conical surface of the annular abutment portion 62d is effectively embedded in the convex curved surface of the second end portion 27, the transmission member 60 is uprightly arranged on the axis S and the protruding rib 62e does not contact the inner peripheral surface 13.

[0166] Then, if Figure 10 As shown, when the electromagnetic actuator A approaches the transmission member 60 from the vertical direction Vd, the guide portion 91 d of the stator 90 comes into contact with the end portion 61 a which is the upper end portion of the transmission member 60 .

[0167] Then, as the electromagnetic actuator A descends, the guide portion 91 d guides the end portion 61 a of the transmission member 60 toward the axis S. Thus, the end portion 61 a of the transmission member 60 and the small-diameter cylindrical portion 61 are guided and inserted into the insertion hole 91 a of the stator 90 .

[0168] Furthermore, when the electromagnetic actuator A descends, the end 61a of the transmission member 60 is guided by the insertion hole 91a of the stator 90, the end 61a of the transmission member 60 is inserted into the accommodating recess 75 of the plunger 70, and the annular abutment portion 62d of the transmission member 60 adapts to the second end 27 of the sliding column 20, so that the transmission member 60 is positioned on the axis S and corrected in an upright state.

[0169] Furthermore, the flange portion 15 of the sleeve 10 abuts against the stator 90 (end yoke 92 ) and is fitted into the fitting recess 152 of the outer yoke 150 .

[0170] Thus, the transmission member 60 is interposed between the spool 20 and the plunger 70 and is positioned on the axis S.

[0171] Then, the front end region of the fitting recess 152 is caulked, thereby completing the assembly work of the electromagnetic switching valve V.

[0172] In the described structure, the end 61a of the transmission member 60 is formed as a convex curved surface, and the guide portion 91d is formed as a concave conical surface. Therefore, during the assembly operation, the end 61a of the transmission member 60 can be smoothly guided onto the axis S along the guide portion 91d of the stator 90 without biting, getting stuck, etc.

[0173] In addition, the annular abutment portion 62d of the transmission member 60 is formed as a concave conical surface, and the second end portion 27 of the slide column 20 is formed as a convex curved surface. Therefore, by making the concave conical surface and the convex curved surface face each other, during the assembly operation, the transmission member 60 and the slide column 20 can be easily centered on the same axis (axis S), and the posture of the transmission member 60 can be easily corrected to an upright state.

[0174] In addition, the inner diameter size of the insertion hole 91a of the stator 90 is formed to limit the transmission member 60 so that the end 61a of the transmission member 60 will not be out of the range that can be inserted into the accommodating recess 75 of the plunger 70. Therefore, during the assembly operation, the end 61a of the transmission member 60 can be easily guided and inserted into the accommodating recess 75 of the plunger 70 without biting, getting stuck, etc.

[0175] In addition, the protrusion serving as the restricted portion protruding from the outer peripheral surface of the transmission member 60 is formed as a plurality of protruding ribs 62e protruding from the outer peripheral surface 62s of the large-diameter cylindrical portion 62 of the transmission member 60, so that the inclination angle of the transmission member 60 from the axis S can be suppressed to a small value during the assembly operation without increasing the protrusion amount of the protruding ribs 62e.

[0176] Furthermore, since the transmission member 60 is formed of a resin material, it can be easily formed into a shape including the plurality of protruding ribs 62 e and the plurality of thinned portions 62 c .

[0177] Next, the switching operation of the electromagnetic switching valve V will be described.

[0178] First, when the coil 132 is not energized, the plunger 70 is moved as shown in FIG. 1 by the force applied by the biasing spring 30 via the spool 20 and the transmission member 60. Figure 11 The stop is shown at a rest position where the second end portion 73 abuts against the stopper 83 .

[0179] Furthermore, the spool 20 stops at a retracted position corresponding to the rest position of the plunger 70 via the transmission member 60 .

[0180] In the retracted position, the first valve portion 22 of the spool 20 closes the oil passage between the first port 11 e and the supply port 11 b and opens the oil passage between the first port 11 e and the discharge port 11 c .

[0181] Furthermore, the second valve portion 23 of the spool 20 is in a state of opening the oil passage between the second port 11 f and the supply port 11 b and closing the oil passage between the second port 11 f and the discharge port 11 d .

[0182] At this time, the first oil passage 5 discharges the hydraulic oil, and the second oil passage 6 supplies the hydraulic oil.

[0183] Then, when the coil 132 is properly energized to generate a magnetic flux potential, the plunger 70 moves forward while resisting the force applied by the biasing spring 30, as shown in FIG. Figure 12 As shown, the first end portion 26 of the slide post 20 abuts against the receiving portion 14 , so that the slide post 20 is positioned at the maximum forward position.

[0184] In the maximum forward position, the first valve portion 22 of the spool 20 opens the oil passage between the first port 11 e and the supply port 11 b and closes the oil passage between the first port 11 e and the discharge port 11 c .

[0185] Furthermore, the second valve portion 23 of the spool 20 is in a state of closing the oil passage between the second port 11 f and the supply port 11 b and opening the oil passage between the second port 11 f and the discharge port 11 d .

[0186] At this time, the first oil passage 5 supplies the hydraulic oil, and the second oil passage 6 discharges the hydraulic oil.

[0187] Furthermore, the spool 20 can be stopped at the intermediate position by appropriately controlling the energization of the coil 132 .

[0188] In the intermediate position, the first valve portion 22 of the spool 20 is in a state of closing the oil passage between the first port 11 e and the supply port 11 b and closing the oil passage between the first port 11 e and the discharge port 11 c .

[0189] Furthermore, the second valve portion 23 of the spool 20 is in a state of closing the oil passage between the second port 11 f and the supply port 11 b and closing the oil passage between the second port 11 f and the discharge port 11 d .

[0190] At this time, the supply and discharge of the hydraulic oil in the first oil passage 5 and the second oil passage 6 are both blocked.

[0191] When the electromagnetic switching valve V performing the switching operation is applied to a valve timing changing device M of a camshaft CS on the intake side of an internal combustion engine, for example, the first oil passage 5 is connected to the advanced angle chamber AC, and the second oil passage 6 is connected to the retarded angle chamber RC.

[0192] Therefore, when the plunger 70 is at the rest position, the valve timing of the intake valve is maintained at the retarded angle position, and when the plunger 70 moves forward according to the operating conditions, the valve timing of the intake valve is positioned at the advanced angle position.

[0193] On the other hand, when the electromagnetic switching valve V performing the switching operation is applied to a valve timing changing device M of a camshaft CS on the exhaust side of an internal combustion engine, for example, the first oil passage 5 is connected to the retard chamber RC and the second oil passage 6 is connected to the advance chamber AC.

[0194] Therefore, when the plunger 70 is in the rest position, the valve timing of the exhaust valve is maintained at the advanced angle position, and when the plunger 70 moves forward according to the operating conditions, the valve timing of the exhaust valve is positioned at the retarded angle position.

[0195] Next, the flow of the hydraulic oil around the plunger 70 and the transmission member 60 in the electromagnetic switching valve V performing the above-described switching operation will be described.

[0196] When the plunger 70 moves forward from the rest position, as shown in FIG. Figure 12 As shown, the hydraulic oil in the forward movement space FS flows into the backward movement space RS defined behind the plunger 70 through the first opening 61d and the first internal passage 61c of the transmission member 60 and the through passage 74 of the plunger 70 as indicated by the arrow. As a result, the plunger 70 can move forward smoothly.

[0197] On the other hand, in the internal space SS of the sleeve 10 , the transmission member 60 is pressed by the plunger 70 and moves forward together with the spool 20 .

[0198] Here, the passage area of ​​the gap G defined around the small-diameter cylindrical portion 61 of the transmission member 60 in the insertion hole 91a of the stator 90 is formed to be smaller than the passage area of ​​the first opening portion 61d, that is, it is formed to be extremely small within a range where the viscous resistance does not increase. Therefore, the working oil in the internal space SS, especially foreign matter, is not easy to flow into the forward moving space FS through the insertion hole 91a.

[0199] In this state, since the distance between the annular step portion 63 and the annular facing portion 91e is increased, the hydraulic oil in the internal space SS is increased. Figure 12 As shown by the arrows in FIG, the hydraulic oil in the second internal passage 61e of the transmission member 60 flows from the second opening 61f to the internal space SS. Furthermore, the hydraulic oil in the internal space SS outside the transmission member 60 flows from the second opening 62b into the second internal passage 62a and the second internal passage 61e. Alternatively, the hydraulic oil near the discharge port 11d and the discharge oil passage 4 flows into the internal space SS through the communication passage 11i. In this manner, the hydraulic oil in the internal space SS circulates around the transmission member 60 as a whole.

[0200] When the plunger 70 moves backward from the forward position toward the rest position, the working oil in the backward movement space RS Figure 11 As shown by the arrow in , the liquid flows through the through passage 74 of the plunger 70 and the first internal passage 61c and the first opening 61d of the transmission member 60 into the forward movement space FS defined in front of the plunger 70. Thus, the plunger 70 can smoothly move backward.

[0201] On the other hand, in the internal space SS of the sleeve 10 , the transmission member 60 moves backward together with the spool 20 following the plunger 70 due to the biasing force of the biasing spring 30 .

[0202] Here, similarly to the above, the passage area of ​​the gap G defined around the small-diameter cylindrical portion 61 of the transmission member 60 in the insertion hole 91a of the stator 90 is formed to be smaller than the passage area of ​​the first opening portion 61d, that is, it is formed to be extremely small within a range where the viscous resistance does not increase, so the working oil in the internal space SS, especially foreign matter, is not easy to flow into the forward moving space FS through the insertion hole 91a.

[0203] In this state, since the distance between the annular step portion 63 and the annular facing portion 91e is narrowed, the hydraulic oil in the internal space SS is reduced as shown in FIG. Figure 11 As shown by the arrows in , the hydraulic oil in the internal space SS outside the transmission member 60 flows from the second opening 61f of the transmission member 60 into the second internal passage 61e. Furthermore, the hydraulic oil in the second internal passages 62a and 61e inside the transmission member 60 flows from the second opening 62b into the internal space SS outside the transmission member 60, or the hydraulic oil in the internal space SS flows out through the communication passage 11i to the discharge port 11d and the discharge oil passage 4. In this manner, the hydraulic oil in the internal space SS circulates around the transmission member 60 as a whole.

[0204] Here, the passage area of ​​the first internal passage 61c is formed to be larger than the passage area of ​​the through passage 74. In addition, the passage area of ​​the first opening portion 61d is formed to be larger than the passage area of ​​the first internal passage 61c. Therefore, when the working oil moves from the forward moving space FS to the backward moving space RS or from the backward moving space RS to the forward moving space FS, the damping effect caused by the contraction resistance can be prevented, thereby enabling the plunger 70 to work smoothly.

[0205] Furthermore, since the annular step portion 63 of the transmission member 60 faces the annular facing portion 91 e of the stator 90 in the axis S direction, the hydraulic oil can be actively circulated in the internal space SS by varying the distance therebetween.

[0206] Therefore, when foreign matter is mixed into the hydraulic oil in the internal space SS, the foreign matter can be prevented from flowing through the insertion hole 91a into the operating area of ​​the plunger 70. This prevents wear or locking of the plunger 70 due to the entry of foreign matter.

[0207] If foreign matter in the hydraulic oil is stuck around the spool 20 , the stuck state can be eliminated by appropriately reciprocating the plunger 70 .

[0208] The electromagnetic switching valve V having the above-described structure simplifies and facilitates assembly work during assembly of the electromagnetic switching valve V. Furthermore, the transmission member 60, which transmits the driving force of the plunger 70 to the spool 20, can be easily assembled while the transmission member 60 is being aligned. Furthermore, after assembly, the electromagnetic switching valve V can be provided that prevents foreign matter in the hydraulic fluid from flowing into the sliding area of ​​the plunger 70 during use.

[0209] Thus, by using the transmission member 60 that is not integrally fixed to the spool 20 or the plunger 70 , the transmission member 60 can be assembled while absorbing slight centering errors, without requiring high-precision centering of the various parts.

[0210] In the embodiment, a transmission member 60 having a small-diameter cylindrical portion 61 and a large-diameter cylindrical portion 62 is shown as a transmission member, but the present invention is not limited to this. A transmission member in which a protrusion protruding from the outer peripheral surface of a cylindrical member having a single outer diameter is provided as a restricted portion may also be used.

[0211] In the embodiment, a plurality of protruding ribs 62e protruding radially from the outer peripheral surface 62s of the large-diameter cylindrical portion 62 are used as the restricted portion of the transmission member, but this is not limited to this. As long as the upper end portion of the transmission member is restricted so as not to escape from the range in which the stator can be inserted into the insertion hole, a restricted portion formed in other forms may also be used.

[0212] In the above embodiment, the transmission member 60 formed of a resin material is shown as the transmission member, but the present invention is not limited thereto, and a transmission member formed of other non-magnetic materials may be employed.

[0213] In the above embodiment, the electromagnetic switching valve V is shown as being fitted into the fitting hole H of the engine body EB, but the present invention is not limited thereto and the electromagnetic switching valve may be installed in other locations.

[0214] [Industrial Applicability]

[0215] As described above, the electromagnetic switching valve according to the present invention can simplify and facilitate the assembly work when it is assembled, and can easily assemble the transmission component that transmits the driving force of the plunger to the sliding column. Therefore, it can certainly be used in engines installed in vehicles such as automobiles or two-wheeled vehicles that are expected to be mass-produced, and can also be effectively used to control the flow of working oil in other hydraulic equipment, etc.

Claims

1. An electromagnetic switching valve, characterized in that: include: a sleeve defining a port communicating with an oil passage for supplying or discharging working oil; a slide column, arranged in the sleeve to freely reciprocate on a specified axis to open and close the port; An electromagnetic actuator comprising a plunger disposed on the axis and a stator for applying magnetomotive force to the plunger; as well as A cylindrical transmission member is arranged on the axis so as to be interposed between the plunger and the slide column to transmit the driving force. The stator includes an insertion hole through which the transmission member is inserted. The transmission member includes a restricted portion, and when the transmission member is dropped into the sleeve from a vertical direction for assembly so that the lower end of the transmission member abuts against the slide column installed in the sleeve, the restricted portion is restricted so that the upper end of the transmission member does not escape from a range that can be inserted into the insertion hole of the stator. The restricted portion includes a protrusion that protrudes from the outer peripheral surface of the transmission member so as to be restricted by contacting the inner peripheral surface of the sleeve. The protrusion includes a plurality of protruding ribs that are discretely arranged along the circumferential direction on the outer peripheral surface of the transmission member.

2. The electromagnetic switching valve according to claim 1, characterized in that: The stator includes a guide portion around the insertion hole, and the guide portion guides the upper end portion of the transmission member toward the axis.

3. The electromagnetic switching valve according to claim 2, characterized in that: The guide portion is formed as a concave tapered surface or a concave curved surface.

4. The electromagnetic switching valve according to claim 1, characterized in that: The lower end portion of the transmission member is formed into a concave tapered surface, The spool includes an end portion formed into a convex curved surface so as to abut against a lower end portion of the transmission member.

5. The electromagnetic switching valve according to claim 1, characterized in that: The upper end portion of the transmission member is formed into a convex curved surface, The plunger includes an accommodating recess formed into a concave tapered surface so as to abut against an upper end portion of the transmission member.

6. The electromagnetic switching valve according to claim 5, characterized in that: The inner diameter of the insertion hole of the stator is formed so as to restrict the transmission member so that the upper end portion of the transmission member does not fall out of a range in which the upper end portion can be inserted into the accommodating recess of the plunger.

7. The electromagnetic switching valve according to claim 1, characterized in that: The transmission member includes a large-diameter cylindrical portion disposed in the sleeve and a small-diameter cylindrical portion inserted into the insertion hole of the stator. The large-diameter cylindrical portion includes the restricted portion.

8. The electromagnetic switching valve according to claim 7, characterized in that: The transmission member includes a thinned portion formed between the plurality of protruding ribs so as to be recessed radially inward from the outer peripheral surface of the large-diameter cylindrical portion.

9. The electromagnetic switching valve according to claim 1, characterized in that: The transmission member is formed of a resin material.

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