JP6395624B2 - Manufacturing method of linear actuator and linear actuator - Google Patents

Description

  The present invention relates to a method for manufacturing a linear actuator including a driving coil and a driving magnet. The present invention also relates to a linear actuator including a driving coil and a driving magnet.

  Conventionally, a linear actuator for moving a predetermined operation object linearly in a predetermined direction is known (for example, see Patent Document 1). The linear actuator described in Patent Document 1 includes a drive coil, a drive magnet unit, a coil holder that holds the drive coil, a magnet holder that holds the drive magnet unit, a coil holder, and a magnet holder. It has a leaf spring that connects the body. The magnet holder is linearly movable relative to the coil holder. The magnet holder includes two case bodies divided in the relative movement direction (vertical direction) of the magnet holder with respect to the coil holder. The two case bodies are made of a soft magnetic material. Further, the two case bodies are formed in a substantially bottomed cylindrical shape, and a magnet holder is formed by welding and fixing the two case bodies in a state where they overlap each other in the vertical direction. The leaf spring includes a coil side fixing part fixed to the coil holding body, a magnet side fixing part arranged on the outer peripheral side of the coil side fixing part and fixed to the magnet holding body, a coil side fixing part and a magnet side fixing part. And a plurality of arm portions connecting the two. The magnet side fixing portion is fixed to the magnet holder in a state of being sandwiched between the two case bodies.

  Conventionally, a lens holding member for holding a lens, a base member and a yoke for holding the lens holding member so as to be movable in the optical axis direction of the lens, and driving the lens holding member in the optical axis direction with respect to the base member and the yoke 2. Description of the Related Art A lens driving device is known that includes a magnet and a coil, a lower plate spring that connects a lens holding member and a base member, and an upper plate spring that connects a lens holding member and a yoke (see, for example, Patent Document 2). . In the lens driving device described in Patent Document 2, the lower leaf spring is composed of a pair of spring pieces. The spring piece includes an outer plate portion fixed to the base member, an inner plate portion fixed to the lens holding member, and a meandering spring plate portion connecting the outer plate portion and the inner plate portion. Before assembling the lens driving device, the pair of spring pieces are connected by a frame portion (hoop material) disposed on the outer peripheral side of the outer plate portion, and the frame portion is cut by a laser when the lens driving device is assembled. Has been removed.

Japanese Patent Laying-Open No. 2015-8573 JP 2012-247655 A

  As in the lens driving device described in Patent Literature 2, when the lower plate spring before assembly of the lens driving device is provided with a frame portion, when the lower plate spring before assembly is handled, the outer plate portion and the inner plate are used. If the frame part is gripped without gripping the part and the spring plate part, the lower leaf spring before assembly can be handled. Therefore, in this lens driving device, it is possible to prevent deformation and damage of the outer plate portion, the inner plate portion, and the spring plate portion when the lower plate spring before assembly is handled. Therefore, for example, in the linear actuator described in Patent Document 1, the inventor of the present application is considering providing a frame portion on a plate spring before the assembly of the linear actuator. However, when the frame portion is provided on the plate spring before the assembly of the linear actuator, a step of cutting and removing the frame portion from the plate spring is required at the time of assembling the linear actuator, and the manufacturing process of the linear actuator becomes complicated.

  Accordingly, an object of the present invention is to provide a linear actuator including a coil holder that holds a drive coil, a magnet holder that holds a drive magnet, and a spring member that connects the coil holder and the magnet holder. An object of the present invention is to provide a method for manufacturing a linear actuator that can simplify the manufacturing process of the linear actuator even if the frame member is provided on the spring member before assembly of the actuator. Another object of the present invention is to provide a linear actuator including a coil holder that holds a drive coil, a magnet holder that holds a drive magnet, and a spring member that connects the coil holder and the magnet holder. An object of the present invention is to provide a linear actuator that can simplify the manufacturing process of the linear actuator even if the frame member is provided on the spring member before the assembly of the actuator.

  In order to solve the above-described problems, a manufacturing method of a linear actuator according to the present invention includes a driving coil wound in a substantially cylindrical shape, a driving magnet disposed on the inner peripheral side of the driving coil, and a driving coil. A cylindrical coil holder that holds the magnet, a magnet holder that holds the drive magnet, and the magnet holder that is linearly movable relative to the coil holder in the axial direction of the winding of the drive coil. If the relative direction of movement of the magnet holder with respect to the coil holder is the first direction, the magnet holder is the outer periphery of at least a part of the coil holder. A coil-side fixing portion that is disposed so as to surround the side and includes a cylindrical first tube portion and a second tube portion that are divided in the first direction, and the spring member is fixed to the coil holder; The magnet is placed on the outer circumference side of the coil side fixed part And a plurality of arm portions connecting the coil side fixing portion and the magnet side fixing portion, and the magnet side fixing portion includes a first tube portion and a second tube portion in the first direction. Is a method of manufacturing a linear actuator disposed between the frame-side fixed portion and the magnet-side fixed portion, which is arranged on the outer peripheral side of the magnet-side fixed portion, and cuts the connection portion between the magnet-side fixed portion with a laser. The cutting and welding step of fixing the magnet side fixing portion to the end surface of the first tube portion by laser welding, and the end surface of the first tube portion and the end surface of the second tube portion after the cutting and welding step are in contact with each other. A cylinder part welding step of fixing the one cylinder part and the second cylinder part by laser welding is provided.

  In the linear actuator manufacturing method of the present invention, in the cutting and welding process, the magnet side fixing portion is fixed to the end surface of the first tube portion by laser welding while cutting the connection portion between the magnet side fixing portion and the frame portion with a laser. Yes. That is, in this invention, when fixing the magnet side fixing | fixed part to the end surface of a 1st cylinder part by laser welding, a frame part is cut | disconnected and removed with a laser. Therefore, in the present invention, it is not necessary to separately provide a process for removing the frame portion when manufacturing the linear actuator. Therefore, in the present invention, it is possible to simplify the manufacturing process of the linear actuator even if the frame portion is provided on the spring member before the assembly of the linear actuator.

  It is preferable that the manufacturing method of the linear actuator of this invention is equipped with the spring welding process which fixes a magnet side fixing | fixed part to the end surface of a 1st cylinder part by laser welding before a cutting welding process. If comprised in this way, even if it is a case where a magnet side fixing | fixed part is fixed to the end surface of a 1st cylinder part by laser welding, cutting the connection location of a magnet side fixing | fixed part and a frame part with a laser in a cutting welding process. Thus, it is possible to prevent the magnet side fixing portion from being displaced in the cutting and welding process.

  In the present invention, in the spring welding process, it is preferable to fix the connecting portion with the arm portion of the magnet side fixing portion to the end surface of the first tube portion by laser welding. Moreover, in this invention, you may fix a connection location with the arm part of a magnet side fixing | fixed part to the end surface of a 1st cylinder part by laser welding at a cutting welding process. If comprised in this way, since it becomes possible to fix the base of an arm part to the end surface of a 1st cylinder part, it becomes possible to make the spring force of an arm part act appropriately.

  In order to solve the above problems, a linear actuator of the present invention includes a drive coil wound in a substantially cylindrical shape, a drive magnet disposed on the inner peripheral side of the drive coil, and a drive coil. A cylindrical coil holder that holds the magnet, a magnet holder that holds the drive magnet, and a magnet holder that can linearly move relative to the coil holder in the axial direction of the winding of the drive coil. And a spring member that connects the coil holding body and the magnet holding body, and the relative direction of movement of the magnet holding body with respect to the coil holding body is the first direction, the magnet holding body is at least part of the outer circumference side of the coil holding body. A coil-side fixing portion fixed to the coil holding body, a coil-side fixing portion that includes a cylindrical first cylinder portion and a second cylinder portion that are divided in the first direction. The magnet holder is arranged on the outer peripheral side of the side fixing part. And a plurality of arm portions that connect the coil side fixing portion and the magnet side fixing portion, and the magnet side fixing portion includes a first cylinder portion and a second cylinder portion in the first direction. A frame-shaped frame portion and a magnet that are arranged between and connected to the magnet-side fixing portion at the outer peripheral side of the magnet-side fixing portion at the boundary portion between the first cylinder portion and the second cylinder portion in the first direction While the connecting part with the side fixing part is cut with a laser, the magnet side fixing part is formed so that the cut welding part which is a mark fixed to the end face of the first tube part by laser welding protrudes to the outer peripheral side, A cylindrical part welded portion, which is a mark where the first cylindrical part and the second cylindrical part are fixed by laser welding, is formed.

  In the linear actuator of the present invention, the magnet side fixing portion is the first while the connecting portion between the magnet side fixing portion and the frame portion is cut by the laser at the boundary portion between the first cylinder portion and the second cylinder portion in the first direction. A cut welding portion, which is a mark fixed to the end face of the cylindrical portion by laser welding, is formed so as to protrude to the outer peripheral side. That is, in the present invention, at the time of manufacturing the linear actuator, the magnet side fixing portion is fixed to the end surface of the first cylindrical portion by laser welding while cutting the connection portion between the magnet side fixing portion and the frame portion with a laser. When the magnet side fixing part is fixed to the end face of one cylinder part by laser welding, the frame part is cut and removed by laser. Therefore, in the present invention, it is not necessary to separately provide a process for removing the frame portion when manufacturing the linear actuator. Therefore, in the present invention, it is possible to simplify the manufacturing process of the linear actuator even if the frame portion is provided on the spring member before the assembly of the linear actuator.

  In the present invention, at the boundary portion between the first tube portion and the second tube portion in the first direction, the trace where the connecting portion with the arm portion of the magnet side fixing portion is fixed to the end surface of the first tube portion by laser welding. It is preferable that a spring weld location is formed. If comprised in this way, since the base of an arm part is being fixed to the end surface of the 1st cylinder part, it becomes possible to make the spring force of an arm part act appropriately.

  In this invention, it is preferable that the cutting welding location is formed in the both sides of the spring welding location in the circumferential direction of a 1st cylinder part and a 2nd cylinder part. If comprised in this way, it will become possible to raise the fixed intensity | strength of the magnet side fixing | fixed part with respect to a 1st cylinder part. Moreover, if comprised in this way, it will become possible to fix a magnet side fixing | fixed part with sufficient balance with respect to a 1st cylinder part.

  In the present invention, it is preferable that a plurality of cutting and welding locations are formed at equal intervals in the circumferential direction of the first cylindrical portion and the second cylindrical portion. That is, before the production of the linear actuator, it is preferable that a plurality of connection portions between the magnet side fixing portion and the frame portion are formed at equal intervals in the circumferential direction of the first cylindrical portion and the second cylindrical portion. If comprised in this way, it will become possible to suppress the bending of a coil side fixing | fixed part, a magnet side fixing | fixed part, and an arm part when a frame part is hold | gripped before manufacture of a linear actuator. Therefore, it becomes possible to prevent deformation and damage of the coil side fixing part, the magnet side fixing part and the arm part before the production of the linear actuator.

  In the present invention, the spring member includes a plurality of magnet side fixing portions that are divided in the circumferential direction of the first cylinder portion and the second cylinder portion, and the magnet side fixing portion is disposed on the end surface of the first cylinder portion. It is preferable that a recess is formed. If comprised in this way, even if the magnet side fixing | fixed part is arrange | positioned between the 1st cylinder part and the 2nd cylinder part in a 1st direction, the end surface of a 1st cylinder part and the end surface of a 2nd cylinder part are ensured. It becomes possible to make it contact | abut. Therefore, the first tube portion and the second tube portion can be easily fixed by laser welding.

  As described above, in the present invention, in the linear actuator including the coil holding body that holds the driving coil, the magnet holding body that holds the driving magnet, and the spring member that connects the coil holding body and the magnet holding body, Even if the frame member is provided on the spring member before the assembly of the linear actuator, the manufacturing process of the linear actuator can be simplified.

It is a perspective view of the linear actuator concerning an embodiment of the invention. It is sectional drawing of the EE cross section of FIG. It is a disassembled perspective view of the linear actuator shown in FIG. FIG. 2 is an exploded perspective view for explaining an assembly procedure of the linear actuator shown in FIG. 1. It is a top view of the 1st case body and spring member shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Configuration of linear actuator)
FIG. 1 is a perspective view of a linear actuator 1 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line EE of FIG. FIG. 3 is an exploded perspective view of the linear actuator 1 shown in FIG.

  The linear actuator 1 (hereinafter referred to as “actuator 1”) of this embodiment is a device for informing that there is an incoming call or the like in a mobile phone or the like, for example, and is used by being mounted on a mobile phone or the like. . The actuator 1 is formed in a flat and substantially cylindrical shape as a whole. Moreover, the actuator 1 is a small thing, for example, the outer diameter of the actuator 1 is about 10 mm-30 mm, and the thickness of the actuator 1 is about 5 mm-10 mm.

  The actuator 1 includes a drive coil 2, a drive magnet 3, a coil holder 4 that holds the drive coil 2, a magnet holder 5 that holds the drive magnet 3, a coil holder 4, and a magnet holder. And a leaf spring 6 as a spring member that connects The magnet holder 5 is linearly movable relative to the coil holder 4. That is, the leaf spring 6 connects the coil holder 4 and the magnet holder 5 so that the magnet holder 5 can move linearly relative to the coil holder 4. In this embodiment, the drive coil 2 and the drive magnet 3 constitute a drive mechanism that moves the magnet holder 5 relative to the coil holder 4.

  In the following description, the relative movement direction of the magnet holder 5 with respect to the coil holder 4 (the Z direction in FIG. 1 and the like) is the vertical direction. Of the Z directions, the Z1 direction side is the “upper” side, and the Z2 direction side is the “lower” side. The vertical direction of this embodiment is a first direction that is a relative movement direction of the magnet holder 5 with respect to the coil holder 4.

  The coil holder 4 is made of a resin material. The coil holder 4 is formed in a cylindrical shape. Specifically, the coil holder 4 is formed in a substantially bottomed cylindrical shape having a bottom portion 4a and a cylindrical portion 4b. The cylinder portion 4b is formed in a substantially cylindrical shape with the vertical direction as the axial direction. On the upper end side of the cylindrical portion 4b, a substantially annular flange portion 4c is formed that extends outward in the radial direction of the cylindrical portion 4b. The bottom part 4a is formed so as to close the lower end of the cylindrical part 4b. A circular through hole 4d penetrating in the vertical direction is formed at the center of the bottom 4a. The driving coil 2 is wound around the outer peripheral surface of the cylindrical portion 4b below the flange portion 4c. The driving coil 2 is wound along the outer peripheral surface of the cylindrical portion 4b, and is wound in a substantially cylindrical shape with the vertical direction as the axial direction of the winding. In this embodiment, the relative movement direction of the magnet holder 5 with respect to the coil holder 4 and the axial direction of the winding of the drive coil 2 are the same.

  The drive magnet 3 is formed in a flat cylindrical shape, and is arranged so that its axial direction and the vertical direction coincide. The driving magnet 3 is disposed on the inner peripheral side of the cylindrical portion 4 b of the coil holding body 4. That is, the driving magnet 3 is disposed on the inner peripheral side of the driving coil 2. The magnet holder 5 includes a disk-shaped magnetic plate 9 on which the upper surface of the driving magnet 3 is fixed, a disk-shaped magnetic plate 10 that is fixed on the lower surface of the driving magnet 3, the magnetic plates 9, 10, and A case body 11 that surrounds the outer peripheral side of the driving magnet 3 and covers the upper surface of the magnetic plate 9 is provided. The case body 11 includes a first case body 12 and a second case body 13 that are divided in the vertical direction.

  The magnetic plates 9, 10, the first case body 12, and the second case body 13 are made of a soft magnetic material. Further, the magnetic plates 9, 10, the first case body 12 and the second case body 13 are made of a metal material. The magnetic plates 9, 10, the first case body 12, and the second case body 13 of this embodiment form yokes for forming a magnetic circuit.

  The first case body 12 is formed in a flat bottomed cylindrical shape, and a cylindrical tube portion 12 a that forms the outer peripheral surface of the first case body 12 and a circle that forms the upper end surface of the first case body 12. And a plate-like end surface portion 12b. The end surface portion 12 b constitutes the upper end surface of the magnet holder 5. The upper surface of the magnetic plate 9 is fixed to the lower surface of the end surface portion 12b. A concave portion 12c in which a magnet side fixing portion 6b (described later) constituting the leaf spring 6 is disposed is formed on the lower end surface of the cylindrical portion 12a. In this embodiment, concave portions 12c are formed at three equal intervals in the circumferential direction of the cylindrical portion 12a at three locations on the lower end surface of the cylindrical portion 12a. That is, a step is formed on the lower end surface of the cylindrical portion 12a at a constant pitch in the circumferential direction of the cylindrical portion 12a.

  The second case body 13 is formed in a flat and substantially cylindrical shape, and includes a cylindrical tube portion 13a constituting the outer peripheral surface of the second case body 12, and a radial direction of the tube portion 13a from the lower end of the tube portion 13a. And an annular bottom 13b extending inward. The inner diameter of the cylinder part 13a is equal to the inner diameter of the cylinder part 12a, and the outer diameter of the cylinder part 13a is equal to the outer diameter of the cylinder part 12a. The 1st case body 12 and the 2nd case body 13 are being fixed by laser welding in the state which the lower end surface of the cylinder part 12a and the upper end surface of the cylinder part 13a are contact | abutting. The cylindrical portions 12 a and 13 a are arranged so as to surround the outer peripheral side of the upper end side portion of the coil holding body 4. The cylinder part 12a of this form is a 1st cylinder part, and the cylinder part 13a is a 2nd cylinder part. In the following description, the circumferential direction (circumferential direction) of the cylindrical portions 12a and 13a is referred to as “circumferential direction”.

  The leaf spring 6 includes a plurality of coil side fixing portions 6a fixed to the coil holding body 4, a magnet side fixing portion 6b fixed to the magnet holding body 5, and a plurality of connecting the coil side fixing portion 6a and the magnet side fixing portion 6b. Arm portion 6c. The coil side fixing portion 6a is formed in a substantially annular shape. The magnet side fixing part 6b is formed in a substantially arc shape. That is, the leaf spring 6 includes a plurality of magnet side fixing portions 6b that are divided in the circumferential direction. The leaf spring 6 of this embodiment includes three magnet side fixing portions 6b arranged at a 120 ° pitch. Moreover, the magnet side fixing | fixed part 6b is formed in the circular arc shape whose center angle becomes about 60 degrees. The three magnet side fixing portions 6b are arranged on the outer peripheral side with respect to the coil side fixing portion 6a. Further, the outer diameter of the magnet side fixing portion 6b formed in a substantially arc shape is substantially equal to the outer diameter of the cylinder portions 12a and 13a, and the inner diameter of the magnet side fixing portion 6b is the inner diameter of the cylinder portions 12a and 13a. It is almost equal.

  The arm portion 6c connects each of the three magnet side fixing portions 6b to the coil side fixing portion 6a. That is, the leaf spring 6 of this embodiment includes three arm portions 6c arranged at a 120 ° pitch. The arm portion 6c is formed in a substantially arc shape, and is disposed between the coil side fixing portion 6a and the magnet side fixing portion 6b in the radial direction of the coil side fixing portion 6a. Moreover, the arm part 6c is connected with the center part of the magnet side fixing | fixed part 6b in the circumferential direction.

  The coil side fixing portion 6 a is fixed to the upper end surface of the coil holding body 4. For example, the coil side fixing portion 6a is fixed to the upper end surface of the coil holding body 4 by welding. The magnet side fixing portion 6b is fixed to the lower end surface of the first case body 12 (that is, the lower end surface of the cylindrical portion 12a). As described above, the concave portion 12c in which the magnet side fixing portion 6b is disposed is formed on the lower end surface of the cylindrical portion 12a. The depth of the concave portion 12c in the vertical direction is substantially equal to the thickness of the magnet side fixing portion 6b (the thickness in the vertical direction), and the width of the concave portion 12c in the circumferential direction is the magnet side fixing portion 6b in the circumferential direction. Slightly wider than the length of. The magnet side fixing part 6b is fixed to the lower end surface of the cylinder part 12a by laser welding in a state of being arranged in the recess 12c, and between the cylinder part 12a and the cylinder part 13a in the vertical direction. Has been placed.

  In the actuator 1, when a current flowing in a predetermined direction is supplied to the driving coil 2, the magnet holder 5 moves upward relative to the coil holder 4, and a current flowing in the opposite direction flows to the driving coil 2. When supplied, the magnet holder 5 moves relative to the coil holder 4 in the downward direction. A fixed plate (not shown) formed in a flat plate shape is fixed to the lower surface of the bottom portion 4 a of the coil holder 4, and a buffer having viscoelasticity is provided between the fixed plate and the magnetic plate 10. A material (not shown) is arranged. This buffer material is formed of, for example, a silicone-based viscoelastic composition and functions to attenuate the vibration of the magnet holder 5. Further, the lower end side portion of the cushioning material is disposed in the through hole 4 d of the bottom portion 4 a of the coil holding body 4.

(Production method of linear actuator)
4 is an exploded perspective view for explaining an assembly procedure of the linear actuator 1 shown in FIG. FIG. 5 is a plan view of the first case body 12 and the leaf spring 6 shown in FIG.

  Hereinafter, the assembly procedure of the actuator 1 will be described. The leaf spring 6 before assembly of the actuator 1 is provided with a frame-like frame portion 6d disposed on the outer peripheral side of the magnet-side fixing portion 6b. The frame portion 6d is formed in an annular shape. In addition, the frame portion 6d is connected to the magnet-side fixing portion 6b via a plurality of connection portions 6e protruding to the inner peripheral side of the frame portion 6d. In this embodiment, six connection portions 6e arranged at equal intervals in the circumferential direction are formed on the plate spring 6 before assembly. That is, six connection portions 6e arranged at a 60 ° pitch are formed in the plate spring 6 before assembly. Moreover, as shown in FIG. 5, each of the six connection parts 6e is connected with each of the both ends of the magnet side fixing | fixed part 6b in the circumferential direction. Specifically, the inner end of the connection portion 6e in the radial direction of the frame portion 6d is connected to both ends of the magnet side fixing portion 6b in the circumferential direction. When viewed from the up and down direction, the width of the connecting portion 6e in the direction orthogonal to the radial direction gradually narrows toward the inner side in the radial direction at the inner end portion of the connecting portion 6e in the radial direction of the frame portion 6d. .

  When assembling the actuator 1, first, the magnetic plates 9, 10 and the driving magnet 3 are fixed to the first case body 12 to assemble a magnet set. Further, the driving coil 2 is wound around the coil holding body 4 and the coil side fixing portion 6 a of the leaf spring 6 is fixed to the upper end surface of the coil holding body 4 to assemble a coil set. Thereafter, the magnet assembly is arranged so that the lower surface of the magnetic plate 10 faces upward, the driving magnet 3 and the magnetic plate 10 are arranged on the inner peripheral side of the coil holding body 4, and the first case body. The coil set is placed on the magnet set from above so that the magnet side fixing portion 6b of the leaf spring 6 is disposed in the twelve recesses 12c.

  Thereafter, the magnet side fixing portion 6b is fixed to the lower end surface of the cylindrical portion 12a of the first case body 12 by laser welding. Specifically, first, a laser is irradiated from the upper side (Z2 direction side) and the outer peripheral side of FIG. 4 to the connecting portion P1 of the magnet side fixing portion 6b with the arm portion 6c, and the arm portion 6c of the magnet side fixing portion 6b. Is connected to the lower end surface of the cylindrical portion 12a by laser welding (spring welding process). Since the leaf spring 6 includes the three magnet side fixing portions 6b and the arm portions 6c, three locations are fixed by laser welding in the spring welding process.

  Thereafter, the connection location between the magnet side fixing portion 6b and the frame portion 6d (specifically, the connection location between the inner end of the connection portion 6e in the radial direction of the frame portion 6d and the magnet side fixing portion 6b) P2 is shown in FIG. Laser is irradiated from the upper side and the outer peripheral side, and the magnet side fixing portion 6b is fixed to the lower end surface of the cylindrical portion 12a by laser welding while cutting the connection portion P2 with the laser (cutting welding process). In this embodiment, since the magnet side fixing portion 6b and the frame portion 6d are connected at six locations, in the cutting and welding process, the magnet side fixing portion 6b is connected to the cylindrical portion 12a while cutting the six connection locations P2 with a laser. Fix to the bottom surface by laser welding. When the cutting and welding process is completed, the fixing of the magnet side fixing portion 6b to the lower end surface of the cylindrical portion 12a is completed.

  Then, after covering the 2nd case body 13 so that the upper end surface of the cylinder part 13a of the 2nd case body 13 may contact | abut the lower end surface of the cylinder part 12a, the lower end surface of the cylinder part 12a, the upper end surface of the cylinder part 13a, In a state where the cylinder part 12a and the cylinder part 13a are in contact with each other, laser is irradiated from the outer peripheral side of the cylinder part 12a and the cylinder part 13a, and the cylinder part 12a and the cylinder part 13a are fixed by laser welding (cylinder part welding process). As described above, the depth of the concave portion 12c in the vertical direction is substantially equal to the thickness of the magnet side fixing portion 6b, and the width of the concave portion 12c in the circumferential direction is slightly wider than the length of the magnet side fixing portion 6b in the circumferential direction. Thus, the portion of the lower end surface of the cylindrical portion 12a where the concave portion 12c is not formed is in contact with the upper end surface of the cylindrical portion 13a. For this reason, in the tube portion welding process, a laser is irradiated to a portion of the lower end surface of the tube portion 12a where the concave portion 12c is not formed and the upper end surface of the tube portion 13a is in contact with the tube portion 12a and the tube portion 12a. The part 13a is fixed. Specifically, between each of the three concave portions 12c in the circumferential direction, two portions are irradiated with laser to fix the cylindrical portion 12a and the cylindrical portion 13a. That is, a total of six places are irradiated with a laser, and the cylinder part 12a and the cylinder part 13a are fixed. In addition, when the tubular portion welding process is completed, the assembly of the actuator 1 is completed.

  As described above, in the spring welding process, the connecting portion P1 between the magnet side fixing portion 6b and the arm portion 6c is fixed to the lower end surface of the cylindrical portion 12a by laser welding. At the boundary portion between the tube portion 12a and the tube portion 13a, a spring welded portion 17 is formed, which is a mark where the connecting portion P1 is fixed to the lower end surface of the tube portion 12a by laser welding (see FIG. 1). Specifically, three spring welds 17 are formed at equal intervals in the circumferential direction (that is, at a pitch of 120 °).

  Moreover, in the cylinder part welding process, since the cylinder part 12a and the cylinder part 13a are fixed by laser welding, in the actuator 1 after assembly, the cylinder part is formed at the boundary between the cylinder part 12a and the cylinder part 13a in the vertical direction. A cylindrical welded portion 18 is formed, which is a mark where 12a and the cylindrical portion 13a are fixed by laser welding (see FIG. 1). Specifically, six cylindrical welded portions 18 are formed.

  Further, in the cutting and welding process, the magnet-side fixing portion 6b is fixed to the lower end surface of the cylindrical portion 12a by laser welding while the connection portion P2 between the magnet-side fixing portion 6b and the frame portion 6d is cut by a laser. In the actuator 1, the magnet-side fixing portion 6b is fixed to the lower end surface of the cylindrical portion 12a by laser welding at the boundary portion between the cylindrical portion 12a and the cylindrical portion 13a in the vertical direction while the connection portion P2 is cut by the laser. The cut welding location 19 is formed (see FIG. 1). Specifically, six cut welded portions 19 are formed at equal intervals in the circumferential direction (that is, at a pitch of 60 °). Further, the cut welded portions 19 are formed on both sides of the spring welded portion 17 in the circumferential direction. Moreover, the cutting welding location 19 is formed so that it may protrude to the outer peripheral side. Specifically, it is formed so as to slightly protrude from the spring welded portion 17 and the tube portion welded portion 18 to the outer peripheral side.

(Main effects of this form)
As described above, in this embodiment, in the cutting and welding process, laser welding is performed on the magnet side fixing portion 6b to the lower end surface of the cylindrical portion 12a while cutting the connection portion P2 between the magnet side fixing portion 6b and the frame portion 6d with a laser. It is fixed with. That is, in this embodiment, when the magnet side fixing part 6b is fixed to the lower end surface of the cylinder part 12a by laser welding, the frame part 6d is removed by cutting with a laser. Therefore, in this embodiment, it is not necessary to separately provide a process for removing the frame portion 6d when the actuator 1 is assembled. Therefore, in this embodiment, the manufacturing process of the actuator 1 can be simplified even if the frame portion 6d is provided in the leaf spring 6 before the assembly of the actuator 1.

  In this embodiment, in the spring welding process prior to the cutting welding process, the connection point P1 between the magnet side fixing part 6b and the arm part 6c is fixed to the lower end surface of the cylindrical part 12a by laser welding. Therefore, in this embodiment, in the cutting and welding step, the magnet side fixing portion 6b is fixed to the lower end surface of the cylindrical portion 12a by laser welding while cutting the connection portion P2 between the magnet side fixing portion 6b and the frame portion 6d with a laser. Even so, it is possible to prevent the magnet-side fixing portion 6b from shifting in the cutting and welding process.

  In the present embodiment, in the spring welding process, the connecting portion P1 with the arm portion 6c of the magnet side fixing portion 6b is fixed to the lower end surface of the cylindrical portion 12a by laser welding, and the cylindrical portion 12a and the cylindrical portion 13a in the vertical direction are fixed. In the boundary portion, a spring welded portion 17 is formed, which is a mark where the connecting portion P1 is fixed to the lower end surface of the cylindrical portion 12a by laser welding. That is, in this embodiment, since the root of the arm portion 6c is fixed to the lower end surface of the cylinder portion 12a, the spring force of the arm portion 6c can be appropriately applied.

  In this embodiment, the cut welding points 19 are formed on both sides of the spring welding point 17 in the circumferential direction. Therefore, in this embodiment, it is possible to increase the fixing strength of the magnet side fixing portion 6b with respect to the cylindrical portion 12a. Further, in this embodiment, it is possible to fix the magnet side fixing portion 6b with respect to the cylindrical portion 12a with a good balance.

  In this embodiment, a concave portion 12c in which the magnet side fixing portion 6b is disposed is formed on the lower end surface of the cylindrical portion 12a. In this embodiment, the depth in the vertical direction of the recess 12c is substantially equal to the thickness of the magnet-side fixing portion 6b, and the width of the recess 12c in the circumferential direction is slightly smaller than the length of the magnet-side fixing portion 6b in the circumferential direction. It is getting wider. Therefore, in this embodiment, even if the magnet-side fixing portion 6b is disposed between the cylindrical portion 12a and the cylindrical portion 13a in the vertical direction, the lower end surface of the cylindrical portion 12a and the upper end surface of the cylindrical portion 13a are reliably contacted. It becomes possible to contact. Therefore, in this embodiment, the cylinder part 12a and the cylinder part 13a can be easily fixed by laser welding.

  In this embodiment, six connection portions 6e are formed on the leaf spring 6 before assembling the actuator 1 at regular intervals in the circumferential direction. Therefore, in this embodiment, it is possible to suppress the bending of the coil side fixing portion 6a, the magnet side fixing portion 6b, and the arm portion 6c when the frame portion 6d is gripped before the actuator 1 is assembled. Therefore, in this embodiment, it is possible to prevent deformation and damage of the coil side fixing portion 6a, the magnet side fixing portion 6b, and the arm portion 6c before the assembly of the actuator 1.

(Other embodiments)
The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited to this, and various modifications can be made without departing from the scope of the present invention.

  In the embodiment described above, the spring welding process is provided before the cutting and welding process, but the spring welding process may not be provided before the cutting and welding process. In this case, in place of the six connection portions 6e formed on the plate spring 6 before assembly in the above-described form, the three connection portions 6e arranged at a 120 ° pitch are replaced by the plate spring 6 before assembly. It is preferable that each of the three connection portions 6e is connected to each of the connection points P1 with the arm portion 6c of the magnet side fixing portion 6b. That is, it is preferable to weld and fix only the connection part P1 with the arm part 6c of the magnet side fixing part 6b while cutting in the cutting welding process. Further, in addition to the six connection portions 6e formed on the plate spring 6 before assembly in the above-described form, three connection portions 6e arranged at a 120 ° pitch are formed on the plate spring 6 before assembly. In addition, each of the three connection portions 6e may be connected to each of the connection points P1 with the arm portion 6c of the magnet side fixing portion 6b. In these cases, the connection place P1 and the connection place P2 coincide with each other at three places.

  With this configuration, when the magnet side fixing portion 6b is fixed to the lower end surface of the cylindrical portion 12a by laser welding while cutting the connection location P2 with a laser in the cutting and welding process, the connecting location P1 is below the cylindrical portion 12a. It is fixed to the end face by laser welding. That is, even if the spring welding process is not provided, the base of the arm portion 6c is fixed to the lower end surface of the cylindrical portion 12a. Therefore, even if the spring welding process is not provided, the spring force of the arm portion 6c can be appropriately applied. In addition, in place of the six connection portions 6e formed on the plate spring 6 before assembly in the above-described form, three connection portions 6e arranged at a 120 ° pitch are formed on the plate spring 6 before assembly. In this case, it is preferable to shorten the length of the magnet side fixing portion 6b in the circumferential direction.

  In the embodiment described above, the leaf spring 6 includes the three magnet side fixing portions 6b formed in an arc shape, but the number of the magnet side fixing portions 6b included in the leaf spring 6 may be two. It may be four or more. Moreover, the leaf | plate spring 6 may be provided with the one magnet side fixing | fixed part 6b formed in an annular | circular shape. Moreover, in the form mentioned above, although the six connection parts 6e formed in the leaf | plate spring 6 before an assembly are arrange | positioned at equal intervals in the circumferential direction, the six connection parts 6e are equal intervals in the circumferential direction. It does not need to be arranged in. Further, the number of connecting portions 6e formed on the plate spring 6 before assembly need not be six. In the above-described embodiment, the actuator 1 is formed in a substantially cylindrical shape, but the actuator 1 may be formed in a polygonal column shape such as a quadrangular column shape.

1 Actuator (linear actuator)
2 Driving coil 3 Driving magnet 4 Coil holder 5 Magnet holder 6 Spring member (leaf spring)
6a Coil side fixing portion 6b Magnet side fixing portion 6c Arm portion 6d Frame portion 12a Tube portion (first tube portion)
12c Concave portion 13a Tube portion (second tube portion)
17 Spring Welding Location 18 Tube Welding Location 19 Cut Welding Location P1 Location of Connection with Arm of Fixed Side on Magnet Side P2 Location of Connection between Frame and Fixed Side on Magnet Side Z First direction (Axis of winding of drive coil) direction)

Claims (9)

A driving coil wound in a substantially cylindrical shape; a driving magnet disposed on an inner peripheral side of the driving coil; a cylindrical coil holder for holding the driving coil; and the driving magnet. A magnet holder for holding, and the coil holder and the magnet holder so that the magnet holder is linearly movable relative to the coil holder in the axial direction of winding of the drive coil. And a spring member that connects
When the relative movement direction of the magnet holder with respect to the coil holder is the first direction,
The magnet holder is disposed so as to surround at least a part of the outer periphery of the coil holder, and includes a cylindrical first tube portion and a second tube portion divided in the first direction,
The spring member includes a coil-side fixing portion that is fixed to the coil holding body, a magnet-side fixing portion that is disposed on the outer peripheral side of the coil-side fixing portion and is fixed to the magnet holding body, and the coil-side fixing portion. And a plurality of arm portions connecting the magnet side fixing portion,
The magnet side fixing portion is a method of manufacturing a linear actuator disposed between the first tube portion and the second tube portion in the first direction,
The magnet side is disposed on the end surface of the first tube portion while cutting a connection portion between the magnet side fixing portion and a frame-like frame portion arranged on the outer peripheral side of the magnet side fixing portion with the magnet side fixing portion. A cutting and welding step of fixing the fixing portion by laser welding, and the first tube portion and the second tube in a state where the end surface of the first tube portion and the end surface of the second tube portion are in contact with each other after the cutting and welding step. A linear actuator manufacturing method comprising: a cylindrical portion welding step for fixing the cylindrical portion by laser welding.   The method for manufacturing a linear actuator according to claim 1, further comprising a spring welding step of fixing the magnet side fixing portion to the end surface of the first tube portion by laser welding before the cutting and welding step.   3. The method of manufacturing a linear actuator according to claim 2, wherein, in the spring welding step, a connecting portion between the magnet side fixing portion and the arm portion is fixed to an end surface of the first cylindrical portion by laser welding.   3. The method of manufacturing a linear actuator according to claim 1, wherein, in the cutting and welding step, a connecting portion of the magnet side fixing portion with the arm portion is fixed to an end surface of the first cylindrical portion by laser welding. . A driving coil wound in a substantially cylindrical shape; a driving magnet disposed on an inner peripheral side of the driving coil; a cylindrical coil holder for holding the driving coil; and the driving magnet. A magnet holder for holding, and the coil holder and the magnet holder so that the magnet holder is linearly movable relative to the coil holder in the axial direction of winding of the drive coil. And a spring member that connects
When the relative movement direction of the magnet holder with respect to the coil holder is the first direction,
The magnet holder is disposed so as to surround at least a part of the outer periphery of the coil holder, and includes a cylindrical first tube portion and a second tube portion divided in the first direction,
The spring member includes a coil-side fixing portion that is fixed to the coil holding body, a magnet-side fixing portion that is disposed on the outer peripheral side of the coil-side fixing portion and is fixed to the magnet holding body, and the coil-side fixing portion. And a plurality of arm portions connecting the magnet side fixing portion,
The magnet side fixing portion is disposed between the first tube portion and the second tube portion in the first direction,
A frame-like frame portion arranged on the outer peripheral side of the magnet side fixing portion and connected to the magnet side fixing portion at a boundary portion between the first cylinder portion and the second cylinder portion in the first direction, and the A cut welding spot, which is a mark where the magnet side fixing part is fixed to the end face of the first tube part by laser welding while the connection part with the magnet side fixing part is cut by a laser, is formed so as to protrude to the outer peripheral side. In addition, the linear actuator is characterized in that a cylindrical weld location is formed, which is a trace of the first cylindrical portion and the second cylindrical portion being fixed by laser welding.   At a boundary portion between the first tube portion and the second tube portion in the first direction, a connecting portion with the arm portion of the magnet side fixing portion is fixed to the end surface of the first tube portion by laser welding. The linear actuator according to claim 5, wherein a spring welding portion which is a trace is formed.   The linear actuator according to claim 6, wherein the cutting and welding locations are formed on both sides of the spring welding location in a circumferential direction of the first cylindrical portion and the second cylindrical portion.   The linear actuator according to any one of claims 5 to 7, wherein a plurality of the cut and welded portions are formed at equal intervals in the circumferential direction of the first cylindrical portion and the second cylindrical portion. The spring member includes a plurality of the magnet side fixing portions that are divided in the circumferential direction of the first tube portion and the second tube portion,
The linear actuator according to claim 5, wherein a concave portion in which the magnet side fixing portion is disposed is formed on an end surface of the first cylindrical portion.

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