Actuator

Abstract

To provide an actuator having strength required for a fixing part between a cylindrical member and a lid member constituting a cylindrical case.SOLUTION: A case 5 of an actuator 1 comprises a cylindrical member 20 and a first lid member 21 that closes an opening at one side of the cylindrical member 20. A fixing part 27 fixing the first lid member 21 to the cylindrical member 20 comprises: a first protrusion 81 protruding from the first lid member 21 toward an outer periphery side; a second protrusion 82 protruding from the first lid member 21 toward the outer periphery side, in a second direction X2 of the first protrusion 81; a first recessed part 91, formed on an inner peripheral surface of the cylindrical member 20, into which the first protrusion 81 is inserted; and a second recessed part 92 into which the second protrusion 82 is inserted. In a state where the first protrusion 81 is not yet inserted into the first recessed part 91, a first protrusion width dimension D1 of the first protrusion 81 is larger than a first recessed part width dimension E1 of the first recessed part 91, and a second protrusion width dimension D2 of the second protrusion 82 is larger than a second recessed part width dimension E2 of the second recessed part 92.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an actuator in which a movable body vibrates within a case. [Background technology]

[0002] Such an actuator is described in Patent Document 1. The actuator in this document includes a support having a case, a movable body housed in the case, a connection member connecting the case and the movable body so that they can move relative to each other, and a magnetic drive mechanism for moving the movable body relative to the support. The support includes a holder fixed to the case and a coil held by the holder. The movable body includes a yoke and a magnet fixed to the yoke and facing the coil. The connection member is a viscoelastic body and is disposed between the case and the yoke. The magnetic drive mechanism is composed of the coil of the support and the magnet of the movable body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-13086 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present inventors have proposed an actuator in which a movable body is accommodated in a cylindrical case and the movable body is vibrated along the axis of the case. In such an actuator, the case includes a cylindrical member located on the outer circumferential side of the movable body and a lid member that closes an axial opening of the cylindrical member. A connection member that connects the movable body and the support includes an annular viscoelastic body, an inner frame member fixed to an end face on the inner circumferential side of the viscoelastic body, and an outer frame member fixed to an end face on the outer circumferential surface of the viscoelastic body. The connection member is arranged coaxially with the case. The inner frame member of the connection member is connected to the movable body. The outer frame member is held from the outside in the radial direction and from one side in the axial direction by a holder fixed to the cylindrical member. A lid member abuts against the outer frame member from the other side in the axial direction. The lid member prevents the viscoelastic body from being exposed to the outside of the case and prevents the outer frame member from moving to the other side in the axial direction.

[0005] In such an actuator, when an external impact is applied due to being dropped, for example, an external force acts on the movable body, causing the movable body to move within the case. In addition, when the movable body moves, the force acting on the movable body is transmitted to the lid member via the connecting member. Therefore, when the actuator receives an external impact, a load is applied to the lid member in the axial direction. Therefore, in such an actuator, the fixing portion between the tubular member and the lid member needs to have strength so that the lid member does not fall off from the tubular member when an external impact is received.

[0006] In view of the above problems, an object of the present invention is to provide an actuator having strength in the fixed portion between the cylindrical member and the cover member that constitute the cylindrical case. [Means for solving the problem]

[0007] In order to achieve the above object, an actuator according to the present invention includes a case including a cylindrical member and a cover member that is inserted into the cylindrical member and closes one opening in an axial direction of the cylindrical member, a movable body contained in the case, a connection member that connects the movable body and the case so as to be relatively movable in the axial direction, and a magnetic drive mechanism that vibrates the movable body in the axial direction relative to the case, wherein the case includes a plurality of fixing parts that fix the cover member to the cylindrical member, and when one of the axial directions is defined as a first direction and the other as a second direction, the cover member includes an abutment part that abuts against the connection member from the side in the first direction, and each fixing part is disposed around a periphery of the cover member. a first protrusion protruding outward from a portion of the circumferential direction of the cover member in the second direction, a second protrusion protruding outward from a portion of the circumferential direction of the first protrusion in the second direction, a first recess provided on an inner circumferential surface of the cylindrical member and into which the first protrusion is inserted, and a second recess provided on the inner circumferential surface of the cylindrical member and into which the second protrusion is inserted, wherein a pair of first end faces located at both ends of the circumferential direction of the first protrusion contact a pair of first side walls of the first recess opposed to each other in the circumferential direction, and a pair of second end faces located at both ends of the circumferential direction of the second protrusion contact a pair of first side walls of the first recess opposed to each other in the circumferential direction, the first projection contacts each of a pair of second side walls of the second recess facing each other in the circumferential direction, a first contact area where each first end face contacts each first side wall is larger than a second contact area where each second end face contacts each second side wall, and before the first projection is inserted into the first recess, a first projection width dimension between the pair of first end faces in the circumferential direction is larger than a first recess width dimension between the pair of first side walls in the circumferential direction, and a second projection width dimension between the pair of second end faces in the circumferential direction is larger than a second recess width dimension between the pair of second side walls in the circumferential direction.

[0008] In the present invention, the cover member is provided with a first protrusion and a second protrusion protruding outward, and the inner peripheral surface of the tubular member is provided with a first recess into which the first protrusion is inserted and a second recess into which the second protrusion is inserted. In addition, before the first protrusion is inserted into the first recess, the first protrusion width dimension of the first protrusion is larger than the first recess width dimension of the first recess, and the second protrusion width dimension of the second protrusion is larger than the second recess width dimension of the second recess. Therefore, when the cover member is inserted into the tubular member and fixed thereto, in each fixing portion, the first protrusion is pressed into the first recess, and the second protrusion is pressed into the second recess. Therefore, the plurality of fixing portions can provide a strength sufficient to prevent the cover member from falling off the tubular member. In addition, each fixing portion is provided with two press-in portions. Therefore, even if the first protrusion or the second protrusion is damaged by an external impact and the press-in portion becomes one, the cover member can be prevented from falling off the tubular member. Furthermore, the first contact area where the first end face of the first projection contacts the first side wall of the first recess is larger than the second contact area where the second end face of the second projection contacts the second side wall of the second recess. This increases the frictional force between the first end face of the first projection and the first side wall of the first recess, making it easier to prevent the lid member from falling off the tubular member. Here, in the actuator, when the vibration of the movable body is transmitted to the lid member via the connecting member, the vibration causes the lid member to rotate around the axis, making the lid member more likely to fall off the tubular member. In contrast, in the present invention, the first contact area where the first end face of the first projection contacts the first side wall of the first recess is larger than the second contact area where the second end face of the second projection contacts the second side wall of the second recess. Therefore, the contact between the first end face of the first projection and the first side wall of the first recess can prevent the lid member from rotating relative to the tubular member, and can prevent the lid member from easily falling off the tubular member.

[0009] Also, when the first end face of the first projection and the second end face of the second projection overlap when viewed from the axial direction, and the first side wall of the first recess overlaps with the second side wall of the second recess, the first end face of the first projection and the second end face of the second projection are arranged on a straight line in the axial direction, and the first side wall of the first recess and the second side wall of the second recess are arranged on a straight line in the axial direction. In this case, when an axial force is applied to the cover member, there is a problem that each of the first projections and the second projections is easily removed from the first recess and the second recess in the axial direction. In contrast, in the present invention, each of the first end faces and each of the second end faces can be located at different positions in the circumferential direction, and each of the first side walls and each of the second side walls can be located at different positions in the circumferential direction. In this way, the first end face and the second end face are not arranged on a straight line in the axial direction, and the first side walls and the second side walls are not arranged on a straight line in the axial direction. Therefore, it is easy to prevent the cover member from falling off the cylindrical member.

[0010] In the present invention, the first protrusion width dimension is longer than the second protrusion width dimension, the first recess width dimension is longer than the second recess width dimension, the second protrusion is located circumferentially inside the first protrusion when viewed from the axial direction, and the second recess is located in the second direction of the first recess and communicates with the first recess in the axial direction. In this way, the first protrusion and the second protrusion are provided at a position where they overlap in each fixing portion. Therefore, by pushing each fixing portion in the second direction, the first protrusion and the second protrusion can be inserted into the first recess and the second recess. Furthermore, when viewed from the first direction side, the second protrusion is located inside the first protrusion. Therefore, when the state in which the cover member is fixed to the cylindrical member is viewed from the first direction side, the second protrusion and the second groove into which the second protrusion is inserted can be hidden by the first protrusion.

[0011] In the present invention, a first press-fit allowance obtained by subtracting the width dimension of the first recess from the width dimension of the first protrusion can be equal to or smaller than a second press-fit allowance obtained by subtracting the width dimension of the second recess from the width dimension of the second protrusion. In this way, the strength of each fixing portion can be ensured by pressing the second protrusion into the second recess away from the open end of the tubular portion. Therefore, the first cover member is less likely to fall off the tubular member. In addition, in this way, deformation of the open end of the tubular member can be prevented or suppressed when the first protrusion is pressed into the first recess provided on the side closer to the open end of the tubular portion.

[0012] In the present invention, the first protrusion may protrude more radially outward than the second protrusion, and the first recess may be recessed more radially outward than the second recess. In this way, it is easy to make the first contact area where the first circumferential end face of the first protrusion contacts the first side wall of the first recess larger than the second contact area where the second circumferential end face of the second protrusion contacts the second side wall of the second recess. This makes it easy to increase the frictional force between the first end face of the first protrusion and the first side wall of the first recess, making it easier to prevent the lid member from coming off the tubular member. In addition, since the first contact area between the first end face of the first protrusion and the first side wall of the first recess is large, it is possible to prevent the lid member from rotating relative to the tubular member when vibration of the movable body is transmitted to the lid member.

[0013] In the present invention, each first end surface may be a curved surface that is curved when viewed from the axial direction, and each first side wall may be a transfer surface having a shape transferred from the curved surface. In this way, it is easy to make the first contact area where the first end surface of the first protrusion contacts the first side wall of the first recess larger than the second contact area where the second end surface of the second protrusion contacts the second side wall of the second recess. This makes it easy to increase the frictional force between the first end surface of the first protrusion and the first side wall of the first recess, making it easier to prevent the lid member from coming off the tubular member. In addition, since the first contact area between the first end surface of the first protrusion and the first side wall of the first recess is large, it is possible to prevent the lid member from rotating relative to the tubular member when vibration of the movable body is transmitted to the lid member.

[0014] In the present invention, it is preferable that three or more fixing parts are provided at equal angular intervals. In this way, the multiple fixing parts can easily ensure a strength sufficient to prevent the lid member from falling off the tubular member.

[0015] In the present invention, the connecting member includes a holder fixed inside the case, and the connecting member includes a ring-shaped viscoelastic body expanding in the radial direction, an inner frame member fixed to an end surface on the inner periphery side of the viscoelastic body, and an outer frame member fixed to an end surface on the outer periphery side of the viscoelastic body, and the holder holds the outer frame member from the outer periphery side and the side in the second direction, the inner frame member is connected to the movable body, and the abutting portion abuts against the outer frame member. In this way, the outer frame member of the connecting member can be held in an axially immovable state by the cover member constituting the support and the holder. In addition, the cover can prevent the viscoelastic body of the connecting member from being exposed to the outside of the case. Effect of the Invention

[0016] In the present invention, the first protrusion and the second protrusion provided on the cover member are press-fitted into the first groove and the second groove provided on the inner circumferential surface of the tubular member. Therefore, the multiple fixing parts that fix the cover member and the tubular member provide a strength that prevents the cover member from falling off the tubular member. In addition, the fixing portion is provided with two press-fitting points. Therefore, even if the first protrusion or the second protrusion is damaged by an external impact and only one press-fitting point remains, the lid member can be prevented from falling off the tubular member. Furthermore, the first contact area where the first end face of the first protrusion contacts the first side wall of the first recess is larger than the second contact area where the second end face of the second protrusion contacts the second side wall of the second recess. This increases the frictional force between the first end face of the first protrusion and the first side wall of the first recess, making it easier to prevent the lid member from falling off the tubular member. In addition, the lid member can be prevented from rotating relative to the tubular member. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a perspective view of an actuator according to an embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] 2 is a cross-sectional view taken along line AA in FIG. 1. [Figure 4] FIG. 2 is a cross-sectional view of FIG. [Diagram 5] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] (Overall composition) Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of an actuator 1 according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the actuator 1 shown in FIG. 1. FIGS. 3 and 4 are cross-sectional views of the actuator 1 shown in FIG. 1. FIG. 3 is a cross-sectional view taken along line AA in FIG. 1. FIG. 4 is a cross-sectional view taken along line BB in FIG. 1. FIG. 4 is a cross-sectional view taken along a direction perpendicular to FIG. 3.

[0019] As shown in Fig. 1, the actuator 1 has a cylindrical appearance. As shown in Figs. 3 and 4, the actuator 1 includes a support 2 having a cylindrical case 5, a movable body 3 housed in the case 5, and a first connecting member 11 and a second connecting member 12 that connect the support 2 and the movable body 3 so as to be relatively movable in an axial direction X along an axis L of the case 5. The first connecting member 11 connects the movable body 3 and the support 2 at one end in the axial direction X within the case 5. The second connecting member 12 connects the movable body 3 and the support 2 at the other end in the axial direction within the case 5.

[0020] The actuator 1 also includes a magnetic drive mechanism 6 that moves the movable body 3 in an axial direction X. The magnetic drive mechanism 6 includes a magnet 61 arranged in the movable body 3 and a coil 62 arranged in the support body 2. In the following description, one side of the axial direction X is referred to as a first direction X1, and the other side of the axial direction X is referred to as a second direction X2.

[0021] (First connecting member and second connecting member) As shown in FIG. 2, the first connection member 11 includes a ring-shaped viscoelastic body 10, a first inner frame member 36 fixed to an end face on the inner circumference side of the viscoelastic body 10, and a first outer frame member 51 fixed to an end face on the outer circumference side of the viscoelastic body 10. The viscoelastic body 10 is bonded to the first inner frame member 36 and the first outer frame member 51 by its own adhesiveness. The first inner frame member 36 is fixed to the movable body 3, and the first outer frame member 51 is held by the support 2. The second connection member 12 includes a ring-shaped viscoelastic body 10, a second inner frame member 37 fixed to an end face on the inner circumference side of the viscoelastic body 10, and a second outer frame member 52 fixed to an end face on the outer circumference side of the viscoelastic body 10. The viscoelastic body 10 is bonded to the second inner frame member 37 and the second outer frame member 52 by its own adhesiveness. The second inner frame member 37 is fixed to the movable body 3 , and the second outer frame member 52 is held by the support body 2 .

[0022] The viscoelastic body 10 may be a gel-like material such as silicone gel, natural rubber, diene rubber (e.g., styrene-butadiene rubber, isoprene rubber, butadiene rubber, chloroprene rubber, acrylonitrile-butadiene rubber, etc.), non-diene rubber (e.g., butyl rubber, Various rubber materials such as ethylene-propylene rubber, ethylene-propylene-diene rubber, urethane rubber, silicone rubber, fluororubber, and thermoplastic elastomers, and modified materials thereof can be used. The viscoelastic body 10 may be a composite member that combines a gel-like material, rubber, or a modified material thereof with an elastic body such as a spring.

[0023] (Support) The support 2 includes a case 5 and a coil holder 4 fixed to the inside of the case 5. As shown in Figs. 1 and 2, the case 5 includes a cylindrical tubular member 20, a first cover member 21 that closes an opening of the tubular member 20 in a first direction X1 of an axial direction X, and a second cover member 22 that closes an opening of the tubular member 20 in a second direction X2. The coil holder 4 is tubular and arranged coaxially with the case 5. As shown in Figs. 3 and 4, the coil holder 4 is located between the first cover member 21 and the second cover member 22 on the inner periphery side of the tubular member 20. The coil holder 4 holds the coil 62 and also holds the first outer frame member 51 of the first connection member 11.

[0024] In addition, the support body 2 includes an annular connecting member holding portion 25 protruding from the inner circumferential surface of the tubular member 20. The connecting member holding portion 25 is located between the coil holder 4 and the second cover member 22 in the axial direction X. The connecting member holding portion 25 holds the second outer frame member 52 of the second connecting member 12.

[0025] (Cylindrical member, first cover member, and second cover member) The cylindrical member 20 is made of resin. As shown in FIG. 2, the cylindrical member 20 has a notch portion 65 formed by cutting an edge in a first direction X1 of the axial direction X in a second direction X2. The cylindrical member 20 also has a board holding portion 69 in the second direction X2 of the notch portion 65. A wiring board 7 is fixed to the board holding portion 69. A power supply lead wire 8 is electrically connected to the wiring board 7. A lead wire holding portion 70 that holds the lead wire 8 is provided at a position circumferentially adjacent to the wiring board 7. The lead wire 8 is connected to the coil 62 via the wiring board 7.

[0026] The first cover member 21 is made of resin. The first cover member 21 includes a circular first end plate portion 211 and an annular first side plate portion 212 extending in the second direction X2 from the outer periphery of the first end plate portion 211. The first end plate portion 211 includes an annular rib 213 protruding in the second direction X2 on the inner periphery side of the first side plate portion 212. The rib 213 is coaxial with the first side plate portion 212. A plurality of protrusions 214 protruding in the second direction X2 are provided at equal angular intervals on the end surface of the rib 213 in the second direction. In this example, three protrusions 214 are provided. A cover portion 66 protruding in the second direction X2 is provided on a part of the circumferential direction of the first side plate portion 212.

[0027] 1, the first cover member 21 is inserted into the tubular member 20 from the side in the first direction X1 and fixed to an end portion of the tubular member 20 in the first direction X1. When the first cover member 21 is inserted into the tubular member 20 from the side in the first direction X1, the cover portion 66 is inserted into the cutout portion 65 from the side in the first direction X1. When the cover portion 66 is inserted into the cutout portion 65, a gap is formed between the end edge of the cover portion 66 in the second direction X2 and the cutout portion 65, which is a wiring pull-out portion 60 for pulling out the coil wire 63 of the coil 62 to the outside of the case 5.

[0028] Here, a plurality of fixing parts 27 for fixing the first cover member 21 and the cylindrical member 20 with a predetermined strength are provided in the circumferential direction between them. In this example, the fixing parts 27 are provided at three positions at equal angular intervals. The details of each fixing part 27 will be described later.

[0029] The second cover member 22 is made of resin. The second cover member 22 comprises a circular second end plate portion 221 and an annular second side plate portion 222 extending in the first direction X1 from the outer periphery of the second end plate portion 221. As shown in Figs. 3 and 4, the second cover member 22 comprises an annular rib 223 on the second end plate portion 221. The rib 223 is coaxial with the second side plate portion 222 and protrudes in the first direction X1. The end face of the rib 223 in the second direction has three protrusions 224 protruding in the first direction X1 at equal angular intervals. It is provided.

[0030] The second cover member 22 is inserted into the tubular member 20 from the side in the second direction X2, and fixed to an end portion of the tubular member 20 in the second direction X2. Three fixing portions 27 for fixing the second cover member 22 and the tubular member 20 with a predetermined strength are provided between the second cover member 22 and the tubular member 20 at equal angular intervals in the circumferential direction. Each fixing portion 27 has the same configuration as the fixing portion 27 provided between the first cover member 21 and the tubular member 20.

[0031] (coil holder) 2, the coil holder 4 includes a coil holding portion 40 that holds the coil 62, and a connection member holding portion 41 that holds the first outer frame member 51 of the first connection member 11 in the first direction X1 of the coil holding portion 40. As shown in FIGS. 3 and 4, the coil 62 held by the coil holding portion 40 is located in the center of the case 5 in the axial direction X.

[0032] The connection member holding portion 41 is annular. An annular first recess 43 is provided on the inner peripheral surface of the connection member holding portion 41, which is cut out from the first direction X1 and inner peripheral side. A first step portion 44 is provided at an end portion of the first recess 43 in the second direction X2. The first outer frame member 51 of the first connection member 11 is press-fitted into the first recess 43 from the first direction X1 side. During the press-fitting, the first step portion 44 abuts against the first outer frame member 51 from the second direction X2 side, and positions the first outer frame member 51 in the axial direction X. As a result, the coil holder 4 holds the first outer frame member 51 of the first connection member 11 from the outer peripheral side and the second direction X2 side.

[0033] As shown in Figs. 2 and 3, two terminal pins 63 protrude from the outer periphery of the connection member holding portion 41. Ends of the coil wire 63 drawn from the coil 62 are wound around the two terminal pins 64. When the coil holder 4 is fixed to the case 5, the two terminal pins 64 protrude to the outside of the case 5 through the wiring draw-out portion 60. Here, as shown in Figs. 1, 2, and 3, the two terminal pins 64 protruding to the outside of the case 5 penetrate two holes 71 provided in the wiring board 7 and are electrically connected to lands provided on the edges of the holes 71. This electrically connects the coil wire 63 to the power supply lead wire 8.

[0034] 3 and 4, when the first cover member 21 is fixed to the cylindrical member 20, the protrusion 214 of the first cover member 21 abuts against the first outer frame member 51 from the side in the first direction X1. That is, the protrusion 214 of the first cover member 21 is an abutting portion that abuts against the first outer frame member 51 from the side in the first direction X1. When the first cover member 21 is fixed to the cylindrical member 20, the first cover member 21 prevents the first outer frame member 51 from moving in the first direction X1. In addition, the first cover member 21 prevents the viscoelastic body 10 of the first connecting member 11 from being exposed to the outside.

[0035] (Connection member holding part) The connection member holding portion 25 is located in the second direction X2 of the coil holder 4. The connection member holding portion 25 is annular. An annular second recess 43 is provided on the inner peripheral surface of the connection member holding portion 25, which is cut out from the second direction X2 and the inner peripheral side. A second step portion 45 is provided at an end portion of the second recess 46 in the first direction X1. The second outer frame member 52 of the second connection member 12 is press-fitted into the second recess 46 from the second direction X2 side. During the press-fitting, the second step portion 45 abuts against the second outer frame member 52 from the first direction X1 side, and positions the second outer frame member 52 in the axial direction X. As a result, the connection member holding portion 25 holds the second outer frame member 52 of the second connection member 12 from the outer peripheral side and the first direction X1 side.

[0036] Here, when the second cover member 22 is fixed to the tubular member 20, the protrusion 214 of the second cover member 22 abuts against the second outer frame member 52 from the second direction X2 side. In other words, the protrusion 214 of the second cover member 22 is an abutting portion that abuts against the second outer frame member 52 from the second direction X2 side. When the second cover member 22 is fixed to the tubular member 20, the second cover member 22 is in contact with the second outer frame member 52 from the second direction X2 side. In addition, the second cover member 22 prevents the viscoelastic body 10 of the second connection member 12 from being exposed to the outside.

[0037] (movable body) As shown in Figs. 2 to 4, the movable body 3 has a support shaft 30 extending in an axial direction X at the radial center of the support body 2. The support shaft 30 is a metal round bar. The axis of the support shaft 30 is the axis of the movable body 3 and coincides with the axis L of the case 5. A magnet 61 is supported by the support shaft 30. The magnet 61 has, in its center, an axial hole 610 through which the support shaft 30 passes.

[0038] Further, a yoke 35 is supported on the support shaft 30. The yoke 35 includes a first yoke 31 overlapping the magnet 61 in a first direction X1 of the axial direction X, and a second yoke 32 overlapping the magnet 61 in a second direction X2.

[0039] The first yoke 31 has a disk shape with a predetermined thickness. The first yoke 31 has a shaft hole 310 in the center, through which the support shaft 30 passes. The first yoke 31 is fixed to the surface of the magnet 61 in the first direction X1 by a method such as gluing. Here, the outer diameter dimension of the first yoke 31 is larger than the outer diameter dimension of the magnet 61. Therefore, the outer peripheral surface of the first yoke 31 protrudes radially outward beyond the outer peripheral surface of the magnet 61.

[0040] The second yoke 32 is composed of two members, a cup-shaped first magnetic member 33 and a disk-shaped second magnetic member 34. The first magnetic member 33 includes a circular end plate portion 331 having an axial hole 330 through which the support shaft 30 penetrates at the center, a bent portion 332 bent in the first direction X1 from the outer edge of the end plate portion 331, and a cylindrical portion 333 extending in the first direction X1 from the bent portion 332. The end plate portion 331 of the first magnetic member 33 is fixed to an end face of the magnet 61 in the second direction X2. The second magnetic member 34 has an axial hole 340 through which the support shaft 30 penetrates at the center. The second magnetic member 34 is fixed to the end plate portion 331 of the first magnetic member 33 from the opposite side to the magnet 61. As shown in FIG. 2, the second magnetic member 34 has a plurality of through holes penetrating in the axial direction X on the outer periphery side of the axial hole 340. Each through hole is a weight adjustment portion 38 for adjusting the weight of the movable body 3.

[0041] 3 and 4, the first inner frame member 36 of the first connecting member 11 is fixed to the support shaft 30 in the first direction X1 of the first yoke 31. More specifically, an annular protrusion 361 that protrudes radially inward is provided at the end in the second direction X2 on the inner circumferential surface of the first inner frame member 36, and the support shaft 30 is press-fitted into the center hole of the annular protrusion 361. In this way, the first inner frame member 36 is fixed to the support shaft 30.

[0042] Moreover, the second inner frame member 37 of the second connecting member 12 is fixed to the support shaft 30 from the second direction X2 side of the second yoke 32. More specifically, an annular protrusion 371 that protrudes radially inward is provided on the inner circumferential surface of the second inner frame member 37 at the end in the first direction X1, and the support shaft 30 is press-fitted into the center hole of the annular protrusion 371. In this way, the second inner frame member 37 is fixed to the support shaft 30.

[0043] When the first inner frame member 36 and the second inner frame member 37 are fixed to the support shaft 30, the first inner frame member 36 abuts against the first yoke 31 from the side in the first direction X1. Moreover, the second inner frame member 37 abuts against the second magnetic member 34 from the side in the second direction X2. Therefore, the magnet 61 and the yoke 35 supported by the support shaft 30 are fixed to the support shaft 30 from both sides in the axial direction X by the first inner frame member 36 and the second inner frame member 37.

[0044] When the magnet 61 and the yoke 35 are fixed to the support shaft 30, the magnet 61 and the yoke 35 are located at the center of the support shaft 30 in the axial direction X. The cylindrical portion 333 of the second yoke 32 is located at a position radially outwardly spaced from the outer circumferential surface of the magnet 61 and the outer circumferential surface of the first yoke 31, and is located radially outwardly of the outer circumferential surface of the magnet 61 and the first yoke 31. Here, when the support body 2 and the movable body 3 are connected via the first connecting member 11 and the second connecting member, a part of the coil 62 of the movable body 3 is located between the cylindrical portion 333 of the second yoke 32 and the outer circumferential surface of the magnet 61. In addition, a part of the coil 62 of the movable body 3 is located between the cylindrical portion 333 of the second yoke 32 and the outer circumferential surface of the first yoke 31.

[0045] (Actuator operation) In the actuator 1, when electricity is applied to the coil 62, the magnetic driving mechanism 6 generates a driving force that drives the movable body 3 in the axial direction X. When electricity is cut off to the coil 62, the movable body 3 returns to the origin position by the return force of the viscoelastic body 10. Therefore, by intermittently applying electricity to the coil 62, the movable body 3 vibrates in the axial direction X. In addition, by adjusting the AC waveform applied to the coil 62, the acceleration at which the movable body 3 moves in the first direction X1 of the axial direction X can be made different from the acceleration at which the movable body 3 moves in the second direction X2. Therefore, a person holding a device to which the actuator 1 is attached as a haptic device can feel a vibration having a directionality in the axial direction X. In addition, the actuator 1 can be used to configure a speaker.

[0046] (fixed part) Next, the fixing part 27 that fixes the tubular member 20 and the first lid member 21 will be described in detail. Fig. 5 is an explanatory diagram of the fixing part 27. Note that the fixing part 27 that fixes the second lid member 22 and the tubular member 20 is the same as the fixing part 27 that fixes the first lid member 21 and the tubular member 20. Therefore, the fixing part 27 that fixes the first lid member 21 and the tubular member 20 will be described, and a description of the fixing part 27 that fixes the second lid member 22 and the tubular member 20 will be omitted.

[0047] 1, the first cover member 21 and the cylindrical member 20 have fixing portions 27 at three locations in the circumferential direction about the axis L. The three fixing portions 27 are provided at equal angular intervals. Each fixing portion 27 has the same configuration.

[0048] 5, each fixing portion 27 includes a first protrusion 81 protruding outward from a circumferential portion of the first side plate portion 212 of the first cover member 21, and a second protrusion 82 protruding outward from a circumferential portion of the first cover member 21 in the second direction X2 of the first protrusion 81. Each fixing portion 27 also includes a first recess 91 provided on the inner circumferential surface of the cylindrical member 20 and into which the first protrusion 81 is inserted, and a second recess 92 provided on the inner circumferential surface of the cylindrical member 20 and into which the second protrusion 82 is inserted. The first protrusion 81 is inserted into the first recess 91 from the side in the first direction X1. The second protrusion 82 is inserted into the second recess 92 from the side in the first direction X1.

[0049] The first projection 81 has a pair of first end faces 81a located at both ends in the circumferential direction. The second projection 82 has a pair of second end faces 82a located at both ends in the circumferential direction. A first projection width dimension D1 between the pair of first end faces 81a in the circumferential direction is larger than a second projection width dimension D2 between the pair of second end faces 82a in the circumferential direction. When viewed from the axial direction X, the first projection 81 and the second projection 82 overlap, and the second projection 82 is located inside the first projection 81 in the circumferential direction. In this example, the second projection 82 is located in the central portion of the first projection 81 in the circumferential direction. The first end faces 81a of the first projection 81 and the second end faces 82a of the second projection 82 are located at different positions in the circumferential direction.

[0050] Moreover, the first projection 81 protrudes more radially outward than the second projection 82. Therefore, a projection-side step 83 having an end face facing the second direction X2 is provided between the first projection 81 and the second projection 82.

[0051] Here, each of the first end faces 81a is a curved surface that is curved when viewed from the axial direction X. When viewed from the axial direction X, each of the first end faces 81a is curved in an S shape.

[0052] The first recess 91 has, on its inner wall surface, a pair of first side walls 91a facing each other in the circumferential direction, and a first peripheral wall 91b of a circular arc extending between the pair of first side walls 91a in the circumferential direction. The first peripheral wall 91b faces the radially inward direction of the cylindrical member 20. The second recess 92 has, on its inner wall surface, a pair of second side walls 92a facing each other in the circumferential direction, and a second peripheral wall 92b of a circular arc extending between the pair of first side walls 91a in the circumferential direction. The second peripheral wall 92b faces the radially inward direction of the cylindrical member 20. When viewed from the axial direction X, the first recess 91 and the second recess 92 overlap, and the end of the second recess 92 in the first direction X1 communicates with the central portion of the first recess 91 in the circumferential direction. Therefore, the first side walls 91a of the first recess 91 and the second side walls 92a of the second recess 92 are at different positions in the circumferential direction.

[0053] The first recess 91 is recessed more deeply toward the outer periphery than the second protrusion 82. Therefore, the first peripheral wall 91b is located radially outward than the second peripheral wall 92b. Therefore, a groove-side step 93 having an end face facing the first direction X1 is provided between the first recess 91 and the second recess 92.

[0054] Here, each first side wall 91a is a transferred surface having a shape transferred from the curved surface of the first projection 81. Therefore, each first side wall 91a is a curved surface, and has an S-shape when viewed from the axial direction X.

[0055] In a state in which the first cover member 21 is fixed to the cylindrical member 20, the pair of first end faces 81a of the first projection 81 contact the pair of first side walls 91a of the first recess 91, respectively, and the pair of second end faces 82a of the second projection 82 contact the pair of second side walls 92a of the second recess 92 that face each other in the circumferential direction. A first contact area F1 where each first end face 81a contacts each first side wall 91a is larger than a second contact area F2 where each second end face 82a contacts each second side wall 92a.

[0056] Here, before the first protrusion 81 is inserted into the first recess 91, the first protrusion width dimension D1 of the first protrusion 81 is larger than the first recess width dimension E1 between a pair of first side walls 91a in the circumferential direction of the first recess 91. Also, the second protrusion width dimension D2 of the second protrusion 82 is larger than the second recess width dimension E2 between a pair of second side walls 92a in the circumferential direction of the second recess 92. The first press-fit allowance obtained by subtracting the first recess width dimension E1 from the first protrusion width dimension D1 is equal to or smaller than the second press-fit allowance obtained by subtracting the second recess width dimension E2 from the second protrusion width dimension D2. In this example, the first press-fit allowance is 0.05 mm to 0.1 mm. The second press-fit allowance is 0.1 mm to 0.2 mm.

[0057] (Action and effect) In this example, the first cover member 21 is provided with a first protrusion 81 and a second protrusion 82 protruding outward, and the inner peripheral surface of the tubular member 20 is provided with a first recess 91 into which the first protrusion 81 is inserted and a second recess 92 into which the second protrusion 82 is inserted. In addition, before the first protrusion 81 is inserted into the first recess 91, the first protrusion width dimension D1 of the first protrusion 81 is larger than the first recess width dimension E1 of the first recess 91, and the second protrusion width dimension D2 of the second protrusion 82 is larger than the second recess width dimension E2 of the second recess 92. Therefore, when the first cover member 21 is inserted into the tubular member 20 and fixed thereto, the first protrusion 81 is pressed into the first recess 91 and the second protrusion 82 is pressed into the second recess 92 in each fixing portion 27. Therefore, the multiple fixing portions 27 can provide a strength sufficient to prevent the first cover member 21 from falling off the tubular member 20.

[0058] Furthermore, two press-fitting points are provided in each fixing portion 27. Therefore, even if the first protrusion 81 or the second protrusion 82 is damaged due to an external impact, leaving only one press-fitting point, it is possible to prevent the first cover member 21 from falling off the tubular member 20.

[0059] Furthermore, the first end surface 81a of the first projection 81 comes into contact with the first side wall 91a of the first recess 91. The first contact area F1 is larger than the second contact area F2 where the second end face 82a of the second projection 82 contacts the second side wall 92a of the second recess 92. This increases the frictional force between the first end face 81a of the first projection 81 and the first side wall 91a of the first recess 91, making it easier to prevent the first cover member 21 from coming off the cylindrical member 20.

[0060] Here, in the actuator 1, when the vibration of the movable body 3 is transmitted to the first cover member 21 via the first connecting member 11, the first cover member 21 rotates around the axis L due to the vibration, and the first cover member 21 becomes easily detached from the cylindrical member 20. In contrast, in this example, the first contact area F1 where the first end face 81a of the first projection 81 contacts the first side wall 91a of the first recess 91 is larger than the second contact area F2 where the second end face 82a of the second projection 82 contacts the second side wall 92a of the second recess 92. Therefore, the first cover member 21 can be prevented from rotating relative to the cylindrical member 20 due to the contact between the first end face 81a of the first projection 81 and the first side wall 91a of the first recess 91. Therefore, the first cover member 21 can be prevented from becoming easily detached from the cylindrical member 20.

[0061] In addition, in each fixing portion 27, when the first end face 81a of the first projection 81 and the second end face 82a of the second projection 82 overlap when viewed from the axial direction X, and the first side wall 91a of the first recess 91 and the second side wall 92a of the second recess 92 overlap, the first end face 81a of the first projection 81 and the second end face 82a of the second projection 82 are arranged on a straight line in the axial direction X, and the first side wall 91a of the first recess 91 and the second side wall 92a of the second recess 92 are arranged on a straight line in the axial direction X. In this case, there is a problem that when a force in the axial direction X is applied to the first cover member 21, each of the first projections 81 and the second projections 82 is easily removed from the first recess 91 and the second recess 92 in the axial direction X. In contrast, in this example, the first end faces 81a and the second end faces 82a are located at different positions in the circumferential direction, and the first side walls 91a and the second side walls 92a are located at different positions in the circumferential direction. Therefore, the first end face 81a of the first projection 81 and the second end face 82a of the second projection 82 are not aligned in a straight line in the axial direction X, and the first side wall 91a of the first recess 91 and the second side wall 92a of the second recess 92 are not aligned in a straight line in the axial direction X. This makes it easy to prevent the first cover member 21 from falling off the cylindrical member 20.

[0062] Here, in this example, when viewed from the axial direction X, the second protrusion 82 overlaps with the first protrusion 81. Therefore, when the first cover member 21 is fixed to the tubular member 20, the first protrusion 81 can be pressed into the first recess 91 and the second protrusion 82 can be pressed into the second recess 92 by pushing each fixing portion 27 in the second direction X2. Furthermore, when viewed from the first direction X1 side, the second protrusion 82 is hidden by the first protrusion 81. Therefore, when the state in which the first cover member 21 is fixed to the tubular member 20 is viewed from the first direction X1 side, the second protrusion 82 and the second recess 92 into which the second protrusion 82 is inserted can be hidden by the first protrusion 81.

[0063] Moreover, the first protrusion 81 protrudes more radially outward than the second protrusion 82, and the first recess 91 is recessed more radially outward than the second recess 92. Therefore, the first contact area F1 where the first circumferential end face 81a of the first protrusion 81 contacts the first side wall 91a of the first recess 91 can be made larger than the second contact area F2 where the second circumferential end face 82a of the second protrusion 82 contacts the second side wall 92a of the second recess 92. This increases the frictional force between the first end face 81a of the first protrusion 81 and the first side wall 91a of the first recess 91, making it easier to prevent the first cover member 21 from coming off the cylindrical member 20. In addition, since the first contact area F1 between the first end face 81a of the first protrusion 81 and the first side wall 91a of the first recess 91 is increased, when vibration of the movable body 3 is transmitted to the first cover member 21, the first cover member 21 can be prevented from rotating relative to the tubular member 20.

[0064] Furthermore, in this example, since the first projection 81 protrudes further outward than the second projection 82, a projection-side step 83 having an end face facing the second direction X2 is formed between the first projection 81 and the second projection 82. Meanwhile, since the first recess 91 is recessed deeper outward than the second recess 92, a groove-side step 93 having an end face facing the first direction X1 is formed between the first recess 91 and the second recess 92. Therefore, when each fixing portion 27 is pushed in the second direction X2 to fix the first cover member 21 to the cylindrical member 20, the projection-side step portion 83 and the groove-side step portion 93 come into contact with each other in the axial direction X. Therefore, when fixing the first cover member 21 to the cylindrical member 20, the first cover member 21 can be positioned in the axial direction X.

[0065] In this example, each first end face 81a is a curved surface that is curved when viewed from the axial direction X, and each first side wall 91a is a transferred surface having a shape transferred from the curved surface. Therefore, the first contact area F1 where the first end face 81a of the first protrusion 81 contacts the first side wall 91a of the first recess 91 can be made larger than the second contact area F2 where the second end face 82a of the second protrusion 82 contacts the second side wall 92a of the second recess 92. This increases the frictional force between the first end face 81a of the first protrusion 81 and the first side wall 91a of the first recess 91, making it easier to prevent the first cover member 21 from coming off the cylindrical member 20. In addition, since the first contact area F1 between the first end face 81a of the first protrusion 81 and the first side wall 91a of the first recess 91 is increased, when vibration of the movable body 3 is transmitted to the first cover member 21, the first cover member 21 can be prevented from rotating relative to the tubular member 20.

[0066] Furthermore, in this example, the first press-fitting allowance obtained by subtracting the first recess width dimension E1 from the first protrusion width dimension D1 is equal to or less than the second press-fitting allowance obtained by subtracting the second recess width dimension E2 from the second protrusion width dimension D2. Therefore, by press-fitting the second protrusion 82 into the second recess 92 away from the open end of the tubular member 20, it is possible to ensure a strength greater than that between the second protrusion 82 and the second recess 92 than between the first protrusion 81 and the first recess 91. This makes it difficult for the first cover member 21 to fall off from the tubular member 20. In addition, since the first press-fitting allowance is equal to or less than the second press-fitting allowance, it is possible to prevent or suppress deformation of the open end of the tubular member 20 when the first protrusion 81 is press-fitted into the first recess 91 provided on the side closer to the open end of the tubular member 20.

[0067] Here, in this example, three fixing parts 27 are provided at equal angular intervals. Therefore, the multiple fixing parts 27 make it easy to ensure a strength sufficient to prevent the first lid member 21 from falling off the tubular member 20.

[0068] In this example, the actuator 1 includes a coil holder 4 fixed inside the case 5. The first connection member 11 includes an annular viscoelastic body 10 arranged coaxially with the case 5, a first inner frame member 36 fixed to an end face on the inner periphery side of the viscoelastic body 10, and a first outer frame member 51 fixed to an end face on the outer periphery side of the viscoelastic body 10. The coil holder 4 holds the first outer frame member 51 from the radial outside and the second direction X2 side. The first inner frame member 36 is connected to the movable body 3. The first abutment portion 28 provided on the first cover member 21 abuts against the first outer frame member 51 from the first direction X1 side. Therefore, the first cover member 21 constituting the support 2 and the coil holder 4 can hold the first outer frame member 51 immovably in the axial direction X. In addition, the first cover member 21 can prevent the viscoelastic body 10 from being exposed to the outside of the case 5.

[0069] When the tubular member 20 and the first cover member 21 are made of resin, it is desirable that the hardness of the tubular member 20 is equal to or greater than the hardness of the first cover member 21. In this way, when the first protrusion 81 and the second protrusion 82 of the first cover member 21 are inserted into the first recess 91 and the second recess 92 of the tubular member 20, a change in the outer diameter dimension of the tubular member 20 can be prevented or suppressed.

[0070] (Modification) The first protrusion 81 and the second protrusion 82 provided in the second direction X2 of the first protrusion 81 may be formed at different positions in the circumferential direction. In this case, the first recess 91 and the second recess 92 are provided at different positions in the circumferential direction. In addition, the second recess 92 extends in the axial direction X from the open end of the tubular member 20.

[0071] Furthermore, the pair of first end faces 81a of the first projection 81 may be flat surfaces. Furthermore, the fixing portions 27 may be provided at two locations in the circumferential direction, or at four or more locations. [Explanation of symbols]

[0072] 1...actuator, 2...support, 3...movable body, 4...coil holder, 5...case, 6...magnetic drive mechanism, 7...wiring board, 8...lead wire, 10...viscoelastic body, 11...first connecting member, 12...second connecting member, 20...tubular member, 21...first cover member, 212...second cover member, 25...connecting member holding portion, 27...fixed portion, 30...support shaft, 31...first yoke, 32...second yoke, 33...first magnetic member, 34...second 2 magnetic member, 35...yoke, 36...first inner frame member, 37...second inner frame member, 38...weight adjustment portion, 40...coil holding portion, 41...connection member holding portion, 43...first recess, 44...first step portion, 45...second step portion, 46...second recess, 51...first outer frame member, 52...second outer frame member, 60...wiring lead-out portion, 61...magnet, 62...coil, 63...coil wire, 64...terminal pin, 65...notch portion, 6 6...cover part, 69...board holding part, 70...lead wire holding part, 71...hole, 81...first projection, 81a...first end face, 82...second projection, 82a...second end face, 83...projection side step, 91...first recess, 91a...first side wall, 91b...first peripheral wall, 92...second recess, 92a...second side wall, 92b...second peripheral wall, 93...groove side step, 310...shaft hole of first yoke, 330...shaft hole of first magnetic member, 331...end Plate portion, 332...bent portion, 333...cylindrical portion, 340...shaft hole of second magnetic member, 361...annular protrusion of first inner frame member, 371...annular protrusion 214 of second inner frame member, 610...shaft hole of magnet, D1...first protrusion width dimension, D2...second protrusion width dimension, D2...second protrusion width dimension, E1...first recess width dimension, E2...second recess width dimension, F1...first contact area, F2...second contact area, L...axis of case, X...axial direction

Claims

1. a case including a cylindrical member and a cover member inserted into the cylindrical member to close one opening of the cylindrical member in an axial direction; A movable body accommodated in the case; a connecting member that connects the movable body and the case so as to be relatively movable in the axial direction; a magnetic drive mechanism that vibrates the movable body in the axial direction relative to the case, the case includes a plurality of fixing portions that fix the cover member to the cylindrical member, When one of the axial directions is defined as a first direction and the other is defined as a second direction, the cover member includes an abutment portion that abuts against the connection member from the side of the first direction, Each fixing portion includes a first protrusion protruding outward from a portion of the circumferential direction of the cover member, a second protrusion protruding outward from a portion of the circumferential direction of the cover member in the second direction of the first protrusion, a first recess provided on an inner circumferential surface of the cylindrical member and into which the first protrusion is inserted, and a second recess provided on an inner circumferential surface of the cylindrical member and into which the second protrusion is inserted, a pair of first end faces located at both ends of the first projection in the circumferential direction contact a pair of first side walls of the first recess opposed to each other in the circumferential direction, a pair of second end faces located at both ends of the second projection in the circumferential direction contact a pair of second side walls of the second recess opposed to each other in the circumferential direction, a first contact area where each of the first end faces contacts each of the first side walls is larger than a second contact area where each of the second end faces contacts each of the second side walls; an actuator characterized in that, before the first protrusion is inserted into the first recess, a first protrusion width dimension between the pair of first end faces in the circumferential direction is larger than a first recess width dimension between the pair of first side walls in the circumferential direction, and a second protrusion width dimension between the pair of second end faces in the circumferential direction is larger than a second recess width dimension between the pair of second side walls in the circumferential direction.

2. Each of the first end faces and each of the second end faces are located at different positions in the circumferential direction, The actuator according to claim 1 , wherein each of the first side walls and each of the second side walls are located at different positions in the circumferential direction.

3. The first protrusion width dimension is greater than the second protrusion width dimension, The first recess width dimension is greater than the second recess width dimension, When viewed from the axial direction, the second protrusion is located circumferentially inside of the first protrusion, 3. The actuator according to claim 2, wherein the second recess is located in the second direction of the first recess and communicates with the first recess in the axial direction.

4. 4. The actuator according to claim 1, wherein a first press-fit allowance obtained by subtracting the first recess width dimension from the first protrusion width dimension is equal to or smaller than a second press-fit allowance obtained by subtracting the second recess width dimension from the second protrusion width dimension.

5. The first protrusion protrudes more radially outward than the second protrusion, The actuator according to claim 1 , wherein the first recess is recessed deeper toward the outer periphery than the second recess.

6. Each of the first end surfaces is a curved surface that is curved when viewed from the axial direction, 6. The actuator according to claim 1, wherein each of the first side walls is a transfer surface having a shape transferred from the curved surface.

7. 7. The actuator according to claim 1, wherein three or more of the fixing portions are provided at equal angular intervals.

8. A holder is provided inside the case, the connection member includes an annular viscoelastic body extending in a radial direction, an inner frame member fixed to an end surface on an inner circumferential side of the viscoelastic body, and an outer frame member fixed to an end surface on an outer circumferential side of the viscoelastic body, the holder holds the outer frame member from an outer circumferential side and a side in the second direction, The inner frame member is connected to the movable body, The actuator according to claim 1 , wherein the contact portion contacts the outer frame member.

Images