Actuator

Abstract

To provide an actuator capable of improving the rigidity of a case-shaped yoke in which a plunger, a coil, etc., are included, and improving the impact resistance in actuator driving.SOLUTION: An actuator comprises a plunger which is moved integrally with a shaft axis, a coil, and a box-shaped case in which the plunger and the coil are included. In the case, when one face of the case in a shaft axis direction is defined as a front face and the other face is defined as a back face, the case is configured by combining a first body including the back face, a top face, and a bottom face with a second body including the front face and both side faces, and includes: a snap fit structure composed of a projection which is provided on the back face of the first body, and fitting holes provided at open ends of the pair of side faces of the second body; and a caulking structure composed of caulking parts which are provided at open ends of the top face and the bottom face of the first body, and a notch which is provided on the front face of the second body.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an actuator including a plunger that moves integrally with a shaft, a coil, and a box-shaped case that houses them. [Background technology]

[0002] Vehicles are equipped with various actuators, such as a clutch actuator that operates a clutch. The actuator has a solenoid that serves as a drive source. As an example of the solenoid, a solenoid device is disclosed in Patent Document 1.

[0003] The solenoid device of Patent Document 1 has "a solenoid portion having a pair of coil terminal pieces protruding in a direction perpendicular to the axial direction of the plunger, a connector portion connected to the solenoid portion from the protruding direction of the coil terminal pieces, and an engaging portion provided on the solenoid portion and the connector portion that engage with each other when the connector portion is connected to the solenoid portion."

[0004] The solenoid portion of the solenoid device in Patent Document 1 includes an electromagnet block and a plunger driven by the electromagnet block. The electromagnet block "consists of an upwardly U-shaped yoke, a stopper plunger fixed upright on the central piece of the yoke, a cylindrical coil spool made of insulating synthetic resin with flanges integrally formed on both axial ends and fitted onto the stopper plunger, a coil wound around the coil spool, a yoke cover, etc."

[0005] In Patent Document 1, a protrusion and a notch are formed at the upper ends of both left and right side pieces of the yoke, respectively. Furthermore, a recess and a protrusion are formed at the left and right end faces of the yoke cover, respectively. The yoke cover is then placed over the upper flange, and the recess and protrusion of the yoke cover are fitted into the protrusion and the notch, respectively, thereby fixing the coil spool integrally to the yoke. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 3409435 Summary of the Invention [Problem to be solved by the invention]

[0007] In the configuration in which the protrusions and notches of the yoke are fitted with the recesses and protrusions of the yoke cover as in Patent Document 1, the fixing strength between them is low. Therefore, if an impact occurs due to the movement of the plunger or the like when the actuator is driven, the resulting wear and deformation may cause the fitting to come loose. For this reason, there is room for further improvement in the technology in Patent Document 1.

[0008] In view of these problems, the present invention aims to provide an actuator that can increase the rigidity of a case-shaped yoke that contains a plunger and a coil, thereby improving the impact resistance when the actuator is driven. [Means for solving the problem]

[0009] In order to solve the above problems, a typical configuration of an actuator according to the present invention is an actuator comprising a plunger (movable iron core) that moves integrally with the shaft axis, a coil (solenoid), and a box-shaped case (yoke) that contains them, wherein when one side of the case in the shaft axial direction is the front side and the other side is the back side, the case is formed by combining a first body including the back side, top side, and bottom side, and a second body including the front side and both side sides, and is characterized by having a snap-fit ​​structure consisting of a protrusion provided on the back side of the first body and mating holes provided at the open ends of a pair of side sides of the second body, and a crimped structure consisting of crimped portions provided at the open ends of the top and bottom sides of the first body and a notch provided on the front side of the second body. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide an actuator that can increase the rigidity of a case-shaped yoke that houses a plunger and a coil, and that can improve the shock resistance when the actuator is driven. [Brief explanation of the drawings]

[0011] [Figure 1] 1A and 1B are diagrams illustrating an actuator according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram illustrating the case of FIG. 1. [Figure 3] 4A to 4C are diagrams illustrating assembly of the first body and the second body. [Figure 4] FIG. 4 is an enlarged view of the main part of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Dimensions, materials, and other specific values ​​shown in the embodiments are merely examples for facilitating understanding of the invention and, unless otherwise specified, do not limit the present invention. In this specification and drawings, elements having substantially the same functions and configurations are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present invention are not shown.

[0013] (Actuator 100) FIG. 1 is a diagram illustrating an actuator 100 according to this embodiment. The actuator 100 according to this embodiment shown in FIG. 1 includes a plunger 110, a coil 120, a first fixed iron core 132 (shaft protruding side), a second fixed iron core 134 (shaft retracting side), and a box-shaped case 140. Although it appears that there are two coils 120, the windings are connected, making it "one divided coil." The plunger is a so-called movable iron core, and is configured integrally with the shaft 102. When the coil 120 is energized and enters an excited state, the plunger 110 is attracted to the coil 120 and moves within the case 140 together with the shaft 102.

[0014] The coil 120 (sometimes called a solenoid) generates a magnetic field when energized. The first stationary iron core 132 and the second stationary iron core 134 are disposed inside the coil 120, respectively.

[0015] 1(a) illustrates the actuator 100 when the shaft 102 is retracted. At this time, magnetic flux M1 (indicated by the black arrow) of the holding magnet 126 passes through the plunger 110, the second fixed iron core 134, and the case 140 and returns to the magnet 126. This causes the plunger 110 to be attracted to the second fixed iron core 134, and the retracted state of the shaft 102 is maintained.

[0016] 1(b) is a diagram illustrating the magnetic flux when a current is applied to the coil. When current is applied to the coil 120, a magnetic flux M2 (indicated by the white arrow) is generated in a direction that cancels out M1. Then, on the second stationary core 134 side, the magnetic flux M1 of the magnet 126 is weakened by the magnetic flux M2 of the coil 120, and the attractive force between the plunger 110 and the second stationary core 134 is reduced. On the other hand, on the first stationary core 132 side, the magnetic flux M2 of the coil 120 passes through the plunger 110, the first stationary core 132, and the case 140. As a result, an attractive force is generated between the plunger 110 and the first stationary core 132, and the plunger 110 and the shaft 102 move in the protruding direction (to the left in the figure).

[0017] 1(c) illustrates the actuator 100 when the shaft 102 is protruding. When the plunger 110 abuts against the first stationary iron core 132, the magnetic flux M3 (black arrow) of the magnet 126 passes through the plunger 110, the first stationary iron core 132, and the case 140 and returns to the magnet 126. As a result, the plunger 110 is attracted to the first stationary iron core 132, and the protruding state of the shaft 102 is maintained.

[0018] 1(a) to 1(c) have been described regarding the operation during extension. When retracting the shaft 102, the state shown in Fig. 1(c) can be transitioned to the state shown in Fig. 1(a) by energizing the coil 120 in the opposite direction to that shown in Fig. 1(b).

[0019] (case) Fig. 2 is a diagram illustrating the case 140 of Fig. 1. In this embodiment, one surface of the case 140 in the axial direction of the shaft 102 (the surface in the direction in which the shaft 102 extends) is defined as the front surface 172, and the other surface is defined as the back surface 152. The front surface 172 and the back surface 152 are respectively formed with an insertion hole 172a and an insertion hole 152a through which the shaft 102 is inserted.

[0020] The case 140 of the actuator 100 of this embodiment is formed by combining a first body 150 and a second body 170 shown in Figure 2. The first body 150 forms a back surface 152, a top surface 154, and a bottom surface 156. The second body 170 forms a front surface 172 and a pair of side surfaces 174, 176 (both side surfaces). Fixing feet 174a and fixing feet 176a (see Figure 3) are formed on the pair of side surfaces 174, 176 and are used when attaching the case 140 to a target component (not shown).

[0021] Note that words indicating directions such as front, back, side, top, bottom, left, and right are names used for convenience to facilitate understanding and do not limit the directions in actual use.

[0022] As a feature of this embodiment, first body 150 has protrusions 162 provided on the sides of rear surface 152 and crimped portions 164 provided at the open ends of top surface 154 and bottom surface 156. Second body 170 has fitting holes 182 provided at the open ends of a pair of side surfaces 174, 176 and a notch 184 provided on the front surface.

[0023] According to the above configuration, a snap-fit ​​structure is formed between the protrusion 162 of the first body 150 and the fitting hole 182 of the second body 170. Furthermore, the crimped portion 164 of the first body 150 and the notch 184 of the second body 170 form a crimped structure.

[0024] FIG. 3 is a diagram illustrating the assembly of the first body 150 and the second body 170. FIG. 3(a) illustrates the case 140 in a state before assembly. FIG. 3(b) and FIG. 3(c) illustrate the case 140 in a state after assembly. FIG. 4 is an enlarged view of a main part of FIG. 3(b). FIG. 4(a) is an enlarged view of part A of FIG. 3(b). FIG. 4(b) is an enlarged view of part B of FIG. 3(b).

[0025] (Snap-fit ​​structure) 3(a), when assembling the first body 150 and the second body 170, the open side of the second body 170 is aligned with the open side of the first body 150 and inserted. At this time, the second body 170 is elastically deformed and expanded by the inserted first body 150.

[0026] When the first body 150 has been completely inserted into the second body 170, the protrusion 162 of the first body 150 fits into the fitting hole 182 of the second body 170, forming a snap-fit ​​structure, as shown in FIG. 4(a).

[0027] In particular, in this embodiment, as shown in Fig. 4(a), the insides of the end portions 174b, 176b of the pair of side surface portions 174, 176 (Fig. 4(a) illustrates the end portion 174b of the side surface 174) are tapered. This allows the protrusion 162 to be guided into the second body 170 by the tapered shape.

[0028] In this embodiment, a tapered shape 162a is also formed on the corner on the insertion side of the protrusion 162. This allows the protrusion 162 to be smoothly fitted into the fitting hole 182. This reduces the stress when fitting the protrusion 162 into the fitting hole 182, making assembly within the elastic range easier.

[0029] Furthermore, fitting hole 182 has rounded corners 182a (see FIGS. 2 and 3(c)). This makes it possible to avoid stress concentration when an impact is applied, compared to fitting hole 182 that does not have rounded corners. Therefore, it is possible to effectively prevent damage to fitting hole 182 and, ultimately, second body 170.

[0030] (Crimped structure) When the first body 150 is inserted into the second body 170, the crimped portion 164 of the first body 150 is inserted into the notch 184 of the second body 170. Then, as shown in FIG. 4(b), the crimped portion 164 is crimped so as to expand within the notch 184. This forms a crimped structure, and the first body 150 and the second body 170 are assembled as shown in FIGS. 3(b) and 3(c).

[0031] In particular, in this embodiment, the outer end 184a of the notch is tapered. Therefore, the crimped portion 164 deforms along the tapered shape of the end 184a. With this configuration, the contact area between the crimped portion 164 and the notch 184 is increased, which reduces the surface pressure when an impact is applied. Therefore, it is possible to effectively prevent wear deformation of the crimped portion 164 and the notch 184.

[0032] As described above, according to the actuator 100 of this embodiment, the crimped structure can withstand the load when the shaft 102 is extended and when the shaft 102 is retracted, as shown in Figures 1(a) and 1(b). Even if the crimped structure is slightly deformed by the load, the protrusion 162 and the fitting hole 182 come into contact with each other to support the load, thereby suppressing further deformation of the crimped structure. Therefore, the rigidity of the case-like yoke that houses the plunger 110 and the coil 120 can be increased, and the shock resistance when the actuator is driven can be improved.

[0033] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such examples. It is clear that those skilled in the art can conceive of various modifications and alterations within the scope of the claims, and it is understood that such modifications and alterations also fall within the technical scope of the present invention. [Industrial Applicability]

[0034] The present invention can be used as an actuator including a plunger that moves integrally with a shaft axis, a coil, and a box-shaped case that houses them. [Explanation of symbols]

[0035] 100...actuator, 102...shaft, 110...plunger, 120...coil, 126...magnet, 132...first fixed iron core, 134...second fixed iron core, 140...case, 150...first body, 152...rear face, 152a...insertion hole, 154...top face, 156...bottom face, 162...projection portion, 162a...tapered shape, 164...crimped portion, 170...second body, 172...front face, 172a...insertion hole, 174...side face, 174a...fixed foot, 174b...end portion, 176...side face, 176a...fixed foot, 182...fitting hole, 182a...corner portion, 184...notch, 184a...tapered shape

Claims

[Claim 1] An actuator including a plunger that moves integrally with a shaft axis, a coil, and a box-shaped case that contains them, In the case, when one surface in the shaft axial direction is the front surface and the other surface is the back surface, The case is a first body including the back surface, the top surface, and the bottom surface; a second body including the front surface and both side surfaces; It is a combination of a snap-fit ​​structure formed by a protrusion provided on a rear surface of the first body and fitting holes provided at open ends of a pair of side surfaces of the second body; an actuator having a crimping structure consisting of crimping portions provided at open ends of the top and bottom surfaces of the first body and a notch provided in the front surface of the second body;

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