JP6514880B2 - Linear actuator - Google Patents

Description

  The present invention relates to a linear actuator provided with a magnetic drive mechanism.

  As a linear actuator, in order to drive the movable body in the axial direction, a magnetic drive mechanism provided with a coil and a permanent magnet is provided, and an elastic member consisting of a thin plate elastic member and a coil spring is disposed between the movable body and the fixed body. A configuration that has been proposed is proposed (see Patent Document 1).

JP, 2006-7161, A JP 2002-78310 A

  When a magnetic drive mechanism is used to drive the movable body and the elastic member is provided between the movable body and the fixed body as in the configuration described in Patent Document 1, depending on the frequency at which the movable body reciprocates, There is a problem that resonance occurs and the operation of the movable body can not be controlled.

  In view of the above problems, it is an object of the present invention to effectively suppress the resonance of the movable body even when the magnetic drive mechanism is used to drive the movable body and the spring member is connected to the movable body. To provide a linear actuator that can

In order to solve the above problems, a linear actuator according to the present invention is connected to a fixed body, a movable body, the movable body and the fixed body, and axially moves the movable body with respect to the fixed body. A movable member, a magnetic drive mechanism for driving the movable body in the axial direction, and a gel-like damper member disposed between the fixed body and the movable body; The center of gravity of the body and the connection position of the spring member with respect to the movable body are separated in the axial direction, and the gel-like damper member is positioned on the central axis of the movable body and a position surrounding the central axis The fixed body includes a pivot extending on the central axis, and the movable body includes an axial hole extending on the central axis and the pivot is positioned inside The gel-like damper member , Characterized in that it is arranged in a cylindrical shape between the outer peripheral surface and the inner peripheral surface of the shaft hole of the support shaft. Further, in order to solve the above problems, a linear actuator according to the present invention is connected to a fixed body, a movable body, the movable body, and the fixed body, and the movable body is axially moved relative to the fixed body. A spring member movably supporting the magnetic body, a magnetic drive mechanism for driving the movable body in the axial direction, and a gel-like damper member disposed between the fixed body and the movable body, The center of gravity of the movable body and the connecting position of the spring member with respect to the movable body are separated in the axial direction, and the gel-like damper member is fixed to both the movable body and the fixed body. It features.

In the present invention, since the magnetic drive mechanism is used to drive the movable body and the spring member is connected between the movable body and the fixed body, the propulsive force of the magnetic drive mechanism and the biasing force of the spring member are used. Thus, the movable body can be driven in the axial direction. Even in such a configuration, in the present invention, since the gel damper member is provided between the fixed body and the movable body, the resonance of the movable body can be suppressed. In addition, since the center of gravity of the movable body and the connection position of the spring member with respect to the movable body are separated in the axial direction, even when tilt vibration occurs in the movable body, a radially displacing force is applied to the spring member. . For this reason, since the tilt vibration of the movable body can be reduced, it is possible to suppress the generation of abnormal noise and the decrease in reliability due to the collision between the movable body and the fixed body caused by the tilt vibration of the movable body. Further, since the gel-like damper member is disposed at least one of the position on the central axis of the movable body and the position surrounding the central axis, the resonance of the movable body can be effectively suppressed. Alternatively, since the gel-like damper member is fixed to both the movable body and the fixed body, the gel-like damper member can be prevented from moving with the movement of the movable body. In addition, in the portion where the gel-like damper member is provided, even when the movable body moves in the direction of separating from the fixed body, the gel-like damper member is deformed following the movement to effectively resonate the movable body. Can be suppressed.

In the present invention, the spring member is a plate-like spring member whose thickness direction is directed in the direction along the axial direction, and a fixed body side connecting portion connected to the fixed body and the movable body are connected. A configuration provided with a movable body side connection portion and an arm portion connected to the fixed body side connection portion and the movable body side connection portion can be adopted. According to this configuration, the portion occupied by the spring member in the axial direction can be narrowed. Further, when tilt vibration occurs in the movable body, a force to displace in the radial direction is applied to the arm portion of the spring member, but the resonance frequency with respect to the displacement in the radial direction of the arm portion is high. For this reason, even when tilt vibration occurs in the movable body, resonance does not easily occur. Therefore, since the tilt vibration of the movable body is small, it is possible to suppress the generation of abnormal noise and the decrease in reliability due to the collision between the movable body and the fixed body caused by the tilt vibration of the movable body.

  In the present invention, it is preferable that the magnetic drive mechanism includes a permanent magnet provided on the movable body, and a coil provided on the fixed body and radially opposed to the permanent magnet. it can.

  In the present invention, the fixed body includes a fixed body side facing portion that faces the movable body in the axial direction, and the gel-like damper member is configured to have the fixed body side facing portion and the movable body in the axial direction. It is preferable that it is arrange | positioned between.

  In the present invention, the movable body includes a shaft portion protruding toward the fixed body side facing portion on the central axis, and the gel-like damper member is configured to face the fixed body side facing portion of the shaft portion in the axial direction. The structure arrange | positioned between the end surface of the said, and the said fixed body side opposing part is employable.

  In the present invention, the gel-like damper members may be arranged at three positions surrounding the central axis.

  In the present invention, the gel-like damper member is made of, for example, silicone gel.

  In the present invention, preferably, the gel damper member has a penetration of 90 degrees to 110 degrees. According to this configuration, the gel-like damper member has elasticity sufficient to exhibit the damper function, and the gel-like damper member is less likely to break and scatter.

In the present invention, since the magnetic drive mechanism is used to drive the movable body and the spring member is connected between the movable body and the fixed body, the propulsive force of the magnetic drive mechanism and the biasing force of the spring member are used. Thus, the movable body can be driven in the axial direction. Even in such a configuration, in the present invention, since the gel damper member is provided between the fixed body and the movable body, the resonance of the movable body can be suppressed. Further, since the center of gravity of the movable body and the connecting position of the spring member with respect to the movable body are separated in the axial direction, the inclination vibration of the movable body is small even when tilt vibration occurs in the movable body. It is possible to suppress the generation of abnormal noise and the decrease in reliability due to the collision between the movable body and the fixed body caused by the tilt vibration. Further, since the gel-like damper member is disposed at least one of the position on the central axis of the movable body and the position surrounding the central axis, the resonance of the movable body can be effectively suppressed. Alternatively, since the gel-like damper member is fixed to both the movable body and the fixed body, the gel-like damper member can be prevented from moving with the movement of the movable body. In addition, in the portion where the gel-like damper member is provided, even when the movable body moves in the direction of separating from the fixed body, the gel-like damper member is deformed following the movement to effectively resonate the movable body. Can be suppressed.

It is explanatory drawing of the linear actuator which concerns on Embodiment 1 of this invention. It is the disassembled perspective view which decomposed | disassembled the linear actuator concerning Embodiment 1 of this invention finely. 1 is a cross-sectional view of a linear actuator according to Embodiment 1 of the present invention. It is explanatory drawing of the linear actuator which concerns on Embodiment 2 of this invention. It is the disassembled perspective view which decomposed | disassembled the linear actuator concerning Embodiment 2 of this invention finely. It is sectional drawing of the linear actuator concerning Embodiment 2 of this invention.

  Embodiments of the present invention will be described with reference to the drawings. In the following description, the axis L is the central axis of the movable body 6, and the axis L passes through the center of gravity G of the movable body 6. In the following description, in the direction (axial direction) in which the axis L extends, the side on which the movable body 6 is positioned is referred to as one side L1, and the side on which the base 4 of the fixed body 2 is positioned is referred to as the other side L2. .

First Embodiment
(overall structure)
FIG. 1 is an explanatory view of a linear actuator according to Embodiment 1 of the present invention, and FIGS. 1A and 1B are a perspective view of the linear actuator and an exploded perspective view of the linear actuator. FIG. 2 is an exploded perspective view of the linear actuator according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view of the linear actuator according to Embodiment 1 of the present invention.

  As shown in FIG. 1, FIG. 2 and FIG. 3, the linear actuator 1 of this embodiment has a fixed body 2, a movable body 6, and a spring member 8 connected to the movable body 6 and the fixed body 2. The spring member 8 supports the movable body 6 movably in the direction of the axis L with respect to the fixed body 2. The linear actuator 1 also has a magnetic drive mechanism 5 for driving the movable body 6 in the direction of the axis L. The linear actuator 1 is used, for example, as a device or the like that reports an incoming call or the like by vibration in a field such as a mobile phone.

(Configuration of fixed body 2)
The fixed body 2 has a coil bobbin 3 around which a coil 51 constituting the magnetic drive mechanism 5 is wound, and a base 4 for holding the coil bobbin 3 on the other side L2 in the direction of the axis L (the lower side in the figure). . The coil bobbin 3 has a cylindrical body 31 around which a coil 51 is wound, flanges 32 and 33 expanding in diameter on both sides of the body 31, and the base 4 continuously from the flange 31 from the body 31 The coil bobbin 3 is connected to the base 4 via the projecting portion 35. The protruding portions 35 are provided with terminal portions 361 and 362 in which the end portions of the coil 51 are tangled, and in the terminal portions 361 and 362, the end portions of the coil 51 are connected to the wiring substrate 29.

  The base 4 has a substantially disk shape, and a notch 49 in which the wiring board 29 is disposed is formed. A circular first recess 41 is formed in the center located on the axis L on the surface on one side L1 (upper side in the figure) of the axis L direction of the base 4 and a second recess is formed to surround the axis L 42 are formed. In the present embodiment, the second recesses 42 are formed at equal angular intervals at three locations in the circumferential direction so as to surround the axis L, and the three second recesses 42 are separated from the axis L (from the first recess 41 Distance is equal.

  The first concave portion 41 and the second concave portion 42 are concave portions for arranging a gel damper member 9 (a first gel damper member 91 and a second gel damper member 92) which will be described later.

(Configuration of movable body 6)
The movable body 6 has a shaft 63 fitted in the central hole 530 of the permanent magnet 53 constituting the magnetic drive mechanism 5 and a yoke 67 covering the permanent magnet 53. The shaft 63 has a central axis of the movable body 6. It extends in the direction of the axis L on (axis L). The yoke 67 has a disk-shaped end plate portion 671 that contacts the permanent magnet 53 on one side L1 in the axis L direction, and a cylindrical tube extending from the outer edge of the end plate 671 to the other side L2 in the axis L direction. The cylindrical portion 672 covers the permanent magnet 53 radially outward at a predetermined interval on the outer peripheral surface of the permanent magnet 53. In the present embodiment, the movable body 6 has an annular spacer 65 fixed to the inner peripheral surface of the cylindrical portion 672 and the other side L2 in the direction of the axis L of the end plate portion 671 by a method such as adhesion.

  A circular recess 674 is formed in the center of the end plate portion 671 of the yoke 67 on the other side L2 in the direction of the axis L, and a hole 675 is formed in the center of the recess 674.

  In this embodiment, the end of one side L1 in the direction of the axis L of the shaft 63 is welded at a plurality of circumferential positions S1 in a state of being fitted in the hole 675, and the shaft 63 and the yoke 67 are connected by such welding. There is.

  Further, the movable body 6 has a washer 66 that abuts around the central hole 530 on the other side L2 in the direction of the axis L of the permanent magnet 53, and the end of the other side L2 in the direction of the axis L of the shaft 63 is The washer 66 is welded to the surface of the other side L2 in the direction of the axis L at a plurality of circumferential positions S2. As a result, the permanent magnet 53 is fixed between the washer 66 and the end plate portion 671 of the yoke 67.

  In this embodiment, the permanent magnet 53 is composed of two magnet pieces 531 and 532 sandwiching the disc-shaped core 538 from both sides in the direction of the axis L.

  The movable body 6 has a cover 61 at an end of the other side L2 in the direction of the axis L. The cover 61 has a circular bottom plate portion 611, and a side plate portion 612 projecting from the outer edge of the bottom plate portion 611 to one side L1 in the direction of the axis L. The bottom plate portion 611 is located between the flange portion 33 of the coil bobbin 3 and the base 4. For this reason, the bottom plate portion 611 is formed with an opening 613 that allows the protrusion 35 of the coil bobbin 3 to protrude on one side L1 in the direction of the axis L. Further, in the bottom plate portion 611, concave portions 614 are formed at three locations overlapping with the second concave portions 42 of the base 4.

(Configuration of spring member 8)
The spring member 8 is connected to the fixed body side connecting portion 81 connected to the fixed body 2, the movable body side connecting portion 82 connected to the movable body 6, and a plurality connected to the fixed body side connecting portion 81 and the movable body side connecting portion 82. It is a plate-like spring member provided with a book arm portion 83, and has a thickness direction oriented in a direction along the axis L. In the present embodiment, the movable body side connection portion 82 is annular, and is positioned radially outward of the fixed body side connection portion 81 and the arm portion 83. The fixed body side connecting portion 81 is divided into three in the circumferential direction, and an arm portion 83 extends in the circumferential direction from each of the three fixed body side connecting portions 81. All of these three fixed body side connection parts 81 are connected to the surface of the other side L 2 in the direction of the axis L of the flange part 33 of the coil bobbin 3 by a method such as adhesion or welding.

  In the present embodiment, the movable body side connection portion 82 is sandwiched between the side plate portion 612 of the cover 61 and the end of the other side L2 of the cylindrical portion 672 of the yoke 67, and welding at a plurality of locations S3 in the circumferential direction. , The cover 61 and the yoke 67.

  In a state in which the side plate portion 612 of the cover 61 and the cylindrical portion 672 of the yoke 67 are welded and coupled, the end of the other side L2 of the shaft 63 in the axis L direction is from the movable body 6 (cover 61) in the axis L direction. The shaft portion 631 that protrudes on the other side L 2 (the side of the base 4) is configured, and the end surface 630 (the end surface 630 on the base 4 side) of the other side L 2 in the axis L direction of the shaft portion 631 Against one side L1 in the direction of the axis L.

  In the arm portion 83 of the spring member 8 (plate-like spring member) configured in this manner, the spring constant for the displacement of the movable body 6 in the radial direction is larger than the spring constant for the displacement of the movable body 6 in the axis L direction. is there. Therefore, in the arm portion 83 of the spring member 8, the resonance frequency with respect to the displacement of the movable body 6 in the radial direction is higher than the resonance frequency with respect to the displacement of the movable body 6 in the axis L direction.

(Positional relationship between the center of gravity G of the movable body 6 and the connection position C of the spring member 8 with respect to the movable body 6)
In the linear actuator 1 of this embodiment, in the movable body 6, the shaft 63 is fitted in the central hole 530 of the permanent magnet 53, and the end plate portion 671 of the yoke 67 is in contact with the permanent magnet 53 on one side L1 in the axis L direction. I am in touch. In the movable body 6, the cover 61 is connected to the cylindrical portion 672 of the yoke 67. Therefore, the center of gravity G (see FIG. 3) of the movable body 6 is located on the axis L on the one side L1 from the center in the direction of the axis L of the shaft 63. As a result, the center of gravity G of the movable body 6 is positioned on one side L1 in the direction of the axis L from the magnetic center in the direction of the axis L of the magnetic drive mechanism 5 (center position in the direction of the axis L of the permanent magnet 53, position of the core 538). Do. Here, the movable body side connection portion 82 of the spring member 8 is sandwiched between the side plate portion 612 of the cover 61 and the end of the other side L 2 of the cylindrical portion 672 of the yoke 67. Therefore, the connection position C (see FIG. 3) of the spring member 8 to the movable body 6 is located on the other side L2 in the direction of the axis L with respect to the gravity center G of the movable body 6 And the connection position C of the spring member 8 with respect to the movable body 6 are separated in the direction of the axis L.

(Configuration of gel-like damper member 9)
In the linear actuator 1 of the present embodiment, a gel-like damper member 9 is disposed between the fixed body 2 and the movable body 6. The gel-like damper member 9 is disposed between the fixed body 2 and the movable body 6 at least at one of the position on the axis L and the position surrounding the axis L. In the present embodiment, the gel-like damper member 9 is disposed between the fixed body 2 and the movable body 6 both at the position on the axis L and at the position surrounding the axis L.

  More specifically, in the fixed body 2, the base 4 is a fixed body side facing portion facing the movable body 6 on the other side L 2 in the axis L direction, and the base 4 and the movable body are in the axis L direction. A gel-like damper member 9 is disposed between the two.

  In the present embodiment, first, the columnar first gel-like damper member 91 is disposed as the gel-like damper member 9 in the first concave part 41 of the base 4, and the first gel-like damper member 91 is It is located between the end surface 630 of the shaft portion 631 of the shaft 63 protruding from the movable body 6 on the axis L and the base 4. For this reason, the first gel-like damper member 91 is disposed on the opposite side to the center of gravity G with respect to the connection position C of the spring member 8 in the direction of the axis L. In the first gel-like damper member 91, the surface on one side L1 in the direction of the axis L is fixed to the end surface 630 of the shaft 63 with an adhesive, and the surface on the other side L2 is an adhesive on the bottom of the first recess 41 of the base 4. It is fixed by.

Further, in the three second recesses 42 of the base 4, cylindrical second gel-like damper members 92 are disposed as the gel-like damper members 9 respectively, and the second gel-like damper members 92 have the axis L In the direction, it is located between the cover 61 of the movable body 6 and the base 4. Therefore, the second gel-like damper member 92 has a center of gravity G with respect to the connection position C of the spring member 8 in the direction of the axis L.
And is located on the opposite side.

  The second gel-like damper member 92 is disposed to surround the axis L. More specifically, the second recesses 42 of the base 4 are formed at equal angular intervals at three points around the axis L, and the second gel-like damper members 92 are equally spaced at three points around the axis L Is located in The second gel-like damper member 92 has a surface on one side L1 in the direction of the axis L bonded to the back side of the portion of the cover 61 where the recess 614 is formed, and the surface on the other side L2 is the second recess in the base 4 Bonded to the bottom of 42.

  In the present embodiment, the gel-like damper member 9 is made of silicone gel having a penetration of 90 degrees to 110 degrees. The penetration degree is a depth in which a 1/4 cone needle with a total load of 9.38 g at 25 ° C. enters in 5 seconds as defined in JIS-K-2207 or JIS-K-2220. Is a value expressed in 1/10 mm units, and the smaller the value is, the harder it is.

(Operation)
In the linear actuator 1 of the present embodiment, the movable body 6 is at the origin position where the mass of the movable body 6 and the holding force (biasing force) of the spring member 8 are balanced while the energization of the coil 51 is stopped. In this state, when the coil 51 is energized, the movable body 6 receives a propulsive force by the magnetic drive mechanism 5 and moves to one side L1 in the direction of the axis L against the biasing force of the spring member 8. The amount of movement at that time is defined by the value of the current supplied to the coil 51 and the biasing force of the spring member 8. Then, when the energization of the coil 51 is stopped, the biasing force of the spring member 8 returns to the home position. Therefore, when energization of the coil 51 is performed intermittently, the movable body 6 repeats reciprocating movement in the direction of the axis L.

  Also, when a constant current is supplied to the coil 51, the movable body 6 stops at a position defined by the current value supplied to the coil 51 and the biasing force of the spring member 8.

(Main effects of this form)
In the linear actuator 1 of the present embodiment, the movable body 6 may resonate at a frequency corresponding to the mass of the movable body 6 and the spring constant of the spring member 8 depending on the frequency at which the movable body 6 reciprocates. In the present embodiment, the gel-like damper members 9 (first gel-like damper member 91 and second gel-like damper member 92) are disposed between the base 4 (fixed-body-side facing part) of the fixed body 2 and the cover 61 of the movable body 6. The gel-like damper member 90 is provided, and absorbs the vibration of the movable body 6 while being deformed following the movement of the movable body 6. For this reason, the resonance of the movable body 6 can be suppressed.

  Further, in the linear actuator 1 of the present embodiment, the position of the center of gravity G of the movable body 6 and the connection position C of the spring member 8 with respect to the movable body 6 are separated in the axial line L direction. Therefore, when the movable body 6 is vibrated in the direction of the axis L, the inclination shown by the arrow R1 in FIG. 3 in the movable body 6 due to the deviation between the thrust acting on the movable body 6 and the center of gravity G of the movable body 6 Even when vibration occurs, a force to displace in the radial direction is applied to the arm portion 83 of the spring member 8, and the force to displace in the direction of the axis L is small. Here, in the arm portion 83 of the spring member 8, the resonance frequency with respect to the displacement of the movable body 6 in the radial direction is higher than the resonance frequency with respect to the displacement of the movable body 6 in the axis L direction. Even when it occurs, it is difficult for resonance to occur. Therefore, since the tilt vibration of the movable body 6 is small, it is possible to suppress the generation of abnormal noise caused by the collision between the movable body 6 and the fixed body 2 caused by the tilt vibration of the movable body 6 and the reduction in reliability. .

Further, among the gel-like damper members 9, the first gel-like damper member 91 is provided at a position on the central axis (axis line L) of the movable body 6, and the second gel-like damper member 92 is the center of the movable body 6. It is provided in three places surrounding the axis (axis L). For this reason, the gel-like damper member 9 can effectively suppress the resonance of the movable body 6.

  Further, the gel damper member 9 (the first gel damper member 91 and the second gel damper member 92) is fixed to both the movable body 6 and the fixed body 2. For this reason, it is possible to prevent the gel damper member 9 from moving with the movement of the movable body 6. Further, even when the movable body 6 moves in the direction of separating from the fixed body 2 at the portion where the gel-like damper member 9 is provided, the gel-like damper member 9 deforms following such movement, and the movable body 6 Resonance can be effectively suppressed.

  In addition, the gel damper member 9 has a penetration of 90 degrees to 110 degrees. Therefore, the gel-like damper member 9 has sufficient elasticity to exhibit the damper function, and the gel-like damper member 9 is less likely to break and scatter.

  Further, in the present embodiment, since the spring member 8 is a plate-like spring member, the portion occupied by the spring member 8 in the direction of the axis L can be narrowed.

[Modification of Embodiment 1]
In the first embodiment, both the first gel damper member 91 and the second gel damper member 92 are provided, but only one of them may be provided.

  Moreover, in the said Embodiment 1, although the 2nd gel-like damper member 92 was provided in three places of the circumferential direction, you may provide in four or more places. In addition, the second gel-like damper member 92 may be provided in an annular shape.

Second Embodiment
(overall structure)
FIG. 4 is an explanatory view of a linear actuator according to a second embodiment of the present invention, and FIGS. 2 (a) and 2 (b) are a perspective view of the linear actuator and an exploded perspective view of the linear actuator. FIG. 5 is an exploded perspective view of the linear actuator according to the second embodiment of the present invention. FIG. 6 is a cross-sectional view of a linear actuator according to Embodiment 2 of the present invention. The basic configuration of this embodiment is the same as that of the first embodiment, and therefore the same reference numerals are given to the common parts.

  As shown in FIG. 4, FIG. 5 and FIG. 6, the linear actuator 1 of this embodiment has a fixed body 2, a movable body 6, and a spring member 8 connected to the movable body 6 and the fixed body 2. The spring member 8 supports the movable body 6 movably in the direction of the axis L with respect to the fixed body 2. The linear actuator 1 also has a magnetic drive mechanism 5 for driving the movable body 6 in the direction of the axis L.

(Configuration of fixed body 2)
The fixed body 2 has a coil bobbin 3 around which a coil 51 constituting the magnetic drive mechanism 5 is wound, and a base 4 for holding the coil bobbin 3 on the other side L2 in the direction of the axis L. The coil bobbin 3 has a cylindrical body 31 around which a coil 51 is wound, flanges 32 and 33 expanding in diameter on both sides of the body 31, and the base 4 continuously from the flange 31 from the body 31 The coil bobbin 3 is connected to the base 4 via the projecting portion 35. The protruding portions 35 are provided with terminal portions 361 and 362 in which the end portions of the coil 51 are tangled, and in the terminal portions 361 and 362, the end portions of the coil 51 are connected to the wiring substrate 29.

The base 4 has a substantially disk shape, and a notch 49 in which the wiring board 29 is disposed is formed. In the present embodiment, the fixed body 2 includes a support shaft 45 which protrudes from the base 4 to one side L1 in the direction of the axis L and extends on the axis L. The support shaft 45 has a fixing portion 453 located on the other side L2 in the axis L direction, a flange portion 452 whose diameter is enlarged on one side L1 in the axis L direction of the fixing portion 453, and one side in the axis L direction from the flange portion 452 The support portion 451 protrudes to L 1, and the support portion 451 is thicker than the fixing portion 453. The support portion 451 is a portion that supports the movable body 6, and the fixed portion 453 is a portion that is held by the base 4. Specifically, a recess 44 is formed in the central portion of the base 4, and a hole 46 in which the fixing portion 453 is fitted and fixed is formed in the center of the bottom of the recess 44. With the fixing portion 453 fitted in the hole 46, the flange portion 452 abuts on the bottom of the recess 44 of the base 4. An annular rib-like protrusion 43 is formed around the recess 44 in the base 4.

(Configuration of movable body 6)
The movable body 6 has a cylindrical sleeve 68 fitted in the central hole 530 of the permanent magnet 53 constituting the magnetic drive mechanism 5 and a yoke 67 covering the permanent magnet 53. The cylindrical sleeve 68 is cylindrical, and a hole penetrating in the direction of the axis L is formed in the movable body 6 so as to form an axial hole 69 in which the support shaft 45 is positioned inside. The cylindrical sleeve 68 extends in the direction of the axis L on the central axis (axis L) of the movable body 6. The yoke 67 has a disk-shaped end plate portion 671 that contacts the permanent magnet 53 on one side L1 in the axis L direction, and a cylindrical tube extending from the outer edge of the end plate 671 to the other side L2 in the axis L direction. The cylindrical portion 672 covers the permanent magnet 53 radially outward at a predetermined interval on the outer peripheral surface of the permanent magnet 53. In the present embodiment, the movable body 6 has an annular spacer 65 fixed to the inner peripheral surface of the cylindrical portion 672 and the other side L2 in the direction of the axis L of the end plate portion 671 by a method such as adhesion.

  A hole 675 is formed at the center of the end plate portion 671 of the yoke 67. The end of one side L1 of the cylindrical sleeve 68 in the direction of the axis L is welded at a plurality of circumferential positions S1 in a state of being fitted in the hole 675, and the cylindrical sleeve 68 and the yoke 67 are connected by such welding. There is.

  The movable body 6 also has a washer 66 that abuts around the central hole 530 on the other side L2 in the direction of the axis L of the permanent magnet 53, and the end of the other side L2 in the direction of the axis L of the cylindrical sleeve 68 Is welded to the surface of the other side L2 in the direction of the axis L of the washer 66 at a plurality of points S12 in the circumferential direction. As a result, the permanent magnet 53 is fixed between the washer 66 and the end plate portion 671 of the yoke 67.

  In this embodiment, the permanent magnet 53 is composed of two magnet pieces 531 and 532 sandwiching the disc-shaped core 538 from both sides in the direction of the axis L.

  The movable body 6 also has a cover 61 at an end of the other side L2 in the direction of the axis L. The cover 61 has a circular bottom plate portion 611, and a side plate portion 612 projecting from the outer edge of the bottom plate portion 611 to one side L1 in the direction of the axis L. Here, the bottom plate portion 611 is located between the flange portion 33 of the coil bobbin 3 and the base 4. For this reason, the bottom plate portion 611 is formed with an opening 613 that allows the protrusion 35 of the coil bobbin 3 to protrude on one side L1 in the direction of the axis L. Further, in the bottom plate portion 611, concave portions 614 are formed in two places.

(Configuration of spring member 8)
Similar to the first embodiment, the spring member 8 includes the fixed body side connecting portion 81 connected to the fixed body 2, the movable body side connecting portion 82 connected to the movable body 6, the fixed body side connecting portion 81 and the movable body side connecting portion 82 is a plate-like spring member provided with a plurality of arm portions 83 connected to and 82, and the plate thickness direction is oriented in the direction along the axis L. In the present embodiment, the movable body side connection portion 82 is annular, and is positioned radially outward of the fixed body side connection portion 81 and the arm portion 83. The fixed body side connecting portion 81 is divided into three in the circumferential direction, and an arm portion 83 extends in the circumferential direction from each of the three fixed body side connecting portions 81. All of these three fixed body side connection parts 81 are connected to the surface of the other side L 2 in the direction of the axis L of the flange part 33 of the coil bobbin 3 by a method such as adhesion or welding.

  In the present embodiment, the movable body side connection portion 82 is sandwiched between the side plate portion 612 of the cover 61 and the cylindrical portion 672 of the yoke 67 and is welded to the cover 61 and the yoke 67 by welding at multiple locations S13 in the circumferential direction. It is connected.

  In the arm portion 83 of the spring member 8 (plate-like spring member) configured in this manner, the spring constant for the displacement of the movable body 6 in the radial direction is larger than the spring constant for the displacement of the movable body 6 in the axis L direction. is there. Therefore, in the arm portion 83 of the spring member 8, the resonance frequency with respect to the displacement of the movable body 6 in the radial direction is higher than the resonance frequency with respect to the displacement of the movable body 6 in the axis L direction.

(Positional relationship between the center of gravity G of the movable body 6 and the connection position C of the spring member 8 with respect to the movable body 6)
In the linear actuator 1 of this embodiment, in the movable body 6, the cylindrical sleeve 68 is fitted in the central hole 530 of the permanent magnet 53, and the end plate portion 671 of the yoke 67 is permanent magnet 53 on one side L1 in the axis L direction. In contact with In the movable body 6, the cover 61 is connected to the cylindrical portion 672 of the yoke 67. Therefore, the center of gravity G (see FIG. 6) of the movable body 6 is located on the axis L on one side L1 from the center in the direction of the axis L of the cylindrical sleeve 68. As a result, the center of gravity G of the movable body 6 is positioned on one side L1 in the direction of the axis L from the magnetic center in the direction of the axis L of the magnetic drive mechanism 5 (center position in the direction of the axis L of the permanent magnet 53, position of the core 538). Do. Here, the movable body side connection portion 82 of the spring member 8 is sandwiched between the side plate portion 612 of the cover 61 and the end of the other side L 2 of the cylindrical portion 672 of the yoke 67. Therefore, the connection position C (see FIG. 6) of the spring member 8 to the movable body 6 is located on the other side L2 in the direction of the axis L with respect to the gravity center G of the movable body 6 And the connection position C of the spring member 8 with respect to the movable body 6 are separated in the direction of the axis L.

(Configuration of gel-like damper member 9)
In the linear actuator 1 of the present embodiment, a gel-like damper member 9 is disposed between the fixed body 2 and the movable body 6. The gel-like damper member 9 is disposed between the fixed body 2 and the movable body 6 at least at one of the position on the axis L and the position surrounding the axis L. In the present embodiment, the gel damper member 9 is disposed between the fixed body 2 and the movable body 6 at a position surrounding the axis L.

  More specifically, the inner diameter of the shaft hole 69 of the movable body 6 is larger than the support shaft 45 of the fixed body 2, and the inner peripheral surface of the shaft hole 69 and the outer peripheral surface of the support shaft 45 are separated by a gap. It is arranged. That is, in a state in which the support shaft 45 of the fixed body 2 is inserted into the shaft hole 69 of the movable body 6, a cylindrical space is formed between the inner peripheral surface of the shaft hole 69 and the outer peripheral surface of the support shaft 45 In the present embodiment, the gel-like damper member 9 is disposed so as to fill the space. For this reason, the gel-like damper member 9 is composed of a cylindrical gel-like damper member 90 and is disposed so as to surround the axis L.

  In the present embodiment, the gel damper member 90 has an outer peripheral surface fixed to the inner peripheral surface of the shaft hole 69 by an adhesive and an inner peripheral surface fixed to the outer peripheral surface of the support portion 451 of the support shaft 45 by an adhesive. . Here, the dimension of the gel-like damper member 90 in the direction of the axis L is shorter than that of the support 451 of the support shaft 45. Therefore, both the one side L1 and the other side L2 in the direction of the axis L with respect to the gel-like damper member 90 are empty spaces.

  In the present embodiment, the gel damper member 9 (gel damper member 90) is made of silicone gel having a penetration of 90 degrees to 110 degrees. The penetration degree is a depth in which a 1/4 cone needle with a total load of 9.38 g at 25 ° C. enters in 5 seconds as defined in JIS-K-2207 or JIS-K-2220. Is a value expressed in 1/10 mm units, and the smaller the value is, the harder it is.

(Operation)
Also in the linear actuator 1 of the present embodiment, as in the first embodiment, the movable body 6 holds the mass of the movable body 6 and the holding force (biasing force) of the spring member 8 during a period in which the coil 51 is deenergized. Is at the balanced origin position. In this state, when the coil 51 is energized, the movable body 6 receives a propulsive force by the magnetic drive mechanism 5 and moves to one side L1 in the direction of the axis L against the biasing force of the spring member 8. The amount of movement at that time is defined by the value of the current supplied to the coil 51 and the biasing force of the spring member 8. Then, when the energization of the coil 51 is stopped, the biasing force of the spring member 8 returns to the home position. Therefore, when energization of the coil 51 is performed intermittently, the movable body 6 repeats reciprocating movement in the direction of the axis L.

  Also, when a constant current is supplied to the coil 51, the movable body 6 stops at a position defined by the current value supplied to the coil 51 and the biasing force of the spring member 8.

(Main effects of this form)
In the linear actuator 1 of the present embodiment, the movable body 6 may resonate at a frequency corresponding to the mass of the movable body 6 and the spring constant of the spring member 8 depending on the frequency at which the movable body 6 reciprocates. In the present embodiment, the gel-like damper member 9 (gel-like damper member 90) is provided between the support shaft 45 of the fixed body 2 and the cylindrical sleeve 68 of the movable body 6. The vibration of the movable body 6 is absorbed while being deformed following the movement of the movable body 6. For this reason, the resonance of the movable body 6 can be suppressed.

  Further, also in the linear actuator 1 of the present embodiment, as in the first embodiment, the position of the center of gravity G of the movable body 6 and the connection position C of the spring member 8 with respect to the movable body 6 are separated in the axis L direction. For this reason, even when tilt vibration occurs in the movable body 6, resonance does not easily occur. Therefore, since the tilt vibration of the movable body 6 is small, it is possible to suppress the generation of abnormal noise caused by the collision between the movable body 6 and the fixed body 2 caused by the tilt vibration of the movable body 6 and the reduction in reliability. .

  Further, the gel-like damper member 9 (gel-like damper member 90) has a cylindrical shape surrounding the central axis (axis L) of the movable body 6. For this reason, the gel-like damper member 9 can effectively absorb the vibration of the movable body 6 and suppress the resonance.

  Further, the gel-like damper member 9 (gel-like damper member 90) is fixed to both the movable body 6 and the fixed body 2. For this reason, it is possible to prevent the gel damper member 9 from moving with the movement of the movable body 6.

  Further, in the present embodiment, since the spring member 8 is a plate-like spring member, the portion occupied by the spring member 8 in the direction of the axis L can be narrowed.

[Other Embodiments]
In the above embodiment, a structure in which the gel-like damper member 9 is fixed by an adhesive is adopted, but after providing a precursor for forming the gel-like damper member 9, the precursor is gelled to obtain a gel-like damper The gel-like damper member 9 may be fixed by the adhesive force of the member 9 itself. For example, in the second embodiment, after providing a UV curable precursor for forming the gel-like damper member 9, the precursor is irradiated with UV to be gelled, and the adhesive force of the gel-like damper member 9 itself The gel-like damper member 9 may be fixed.

In the above embodiment, the gel-like damper member 9 is disposed on the opposite side of the center of gravity G with respect to the connection position C of the spring member 8 with respect to the movable body 6 in the axis L direction. The gel damper member 9 may be disposed on the same side as the center of gravity G with respect to the connection position C of the spring member 8 with respect to the above.

  In the above embodiment, in the magnetic drive mechanism 5, the coil 51 provided in the fixed body 2 is opposed to the permanent magnet 53 provided in the movable body 6 at the radially outer side, but the coil 51 is provided in the movable body 6 The present invention may be applied to the linear actuator 1 in which the permanent magnet 53 provided on the fixed body 2 is opposed to the coil 51 in the radial direction outer side.

  In the above embodiment, the gel-like damper member 9 is fixed to the movable body 6 and the fixed body 2 by adhesion, but the gel-like damper member 9 is fitted to the movable body 6 and the fixed body 2 It may be fixed by methods other than adhesion.

1 · · Linear actuator, 2 · · · Fixed body, · · · · · · · · · · · · · · · · · · · · · · · · · · · magnetic drive mechanism, 6 · · · movable body, 8 · · · · Spring member 9, 90 · · Gel-like damper member 45 · · Support shaft (fixed body) 61 · · Cover (movable body) 63 · · · Shaft (movable body) 66 · · · Washer (movable body) , · · · · · · · · · · · · · · · · · · · Yoke (movable body), 68 · · · cylindrical sleeve (movable body), 69 · · shaft hole, 81 · · · · · · · · · · · · · · · · 82 · · · · · · · · · · · · · · · First gel-like damper member, 92 · · second gel-like damper member, 630 · · · end face of shaft · 631 · · shaft portion of shaft · 671 · · · end plate portion 672 · · · · · · · · · · · · · · · · Connection position, G · · · Center of gravity, L · · Axis line

Claims (9)

Fixed body,
Movable body,
A spring member connected to the movable body and the fixed body and supporting the movable body so as to be movable in the axial direction with respect to the fixed body;
A magnetic drive mechanism for driving the movable body in the axial direction;
A gel-like damper member disposed between the fixed body and the movable body;
Have
The center of gravity of the movable body and the connection position of the spring member with respect to the movable body are separated in the axial direction ,
The gel-like damper member is disposed at least one of a position on a central axis of the movable body and a position surrounding the central axis.
The fixed body includes a pivot extending on the central axis,
The movable body is provided with an axial hole which extends on the central axis and in which the support shaft is positioned inside;
The linear actuator characterized in that the gel-like damper member is cylindrically disposed between the outer peripheral surface of the support shaft and the inner peripheral surface of the shaft hole . Fixed body,
Movable body,
A spring member connected to the movable body and the fixed body and supporting the movable body so as to be movable in the axial direction with respect to the fixed body;
A magnetic drive mechanism for driving the movable body in the axial direction;
A gel-like damper member disposed between the fixed body and the movable body;
Have
The center of gravity of the movable body and the connection position of the spring member with respect to the movable body are separated in the axial direction,
The gel-like damper member is characterized and to Brighter near actuator that is fixed to both the movable body and the fixed body. The spring member is a flat spring member whose thickness direction is directed in a direction along the axial direction, and a fixed body side connection portion connected to the fixed body and a movable body side connection portion connected to the movable body When,
Linear actuator according to claim 1 or 2, characterized in that it comprises a, an arm portion that is connected to the fixed body side connecting portion and the movable body side connection portion. The magnetic drive mechanism, a permanent magnet provided on said movable member, provided on the fixed body, according to claim 1 to 3, characterized in that it comprises a coil which faces radially to the permanent magnet The linear actuator according to any one of the above. The fixed body includes a fixed body side facing portion facing the movable body in the axial direction,
The linear actuator according to claim 4, wherein the gel-like damper member is disposed between the fixed body side facing portion and the movable body in the axial direction. The movable body includes a shaft portion protruding toward the fixed body side facing portion on the central axis line,
The linear actuator according to claim 5, wherein the gel-like damper member is disposed between the end face of the shaft portion facing the fixed body side and the fixed body side facing portion in the axial direction. .   The linear actuator according to claim 5, wherein the gel-like damper members are arranged at three positions surrounding the central axis. The linear actuator according to any one of claims 1 to 7 , wherein the gel-like damper member is made of silicone gel. The linear actuator according to any one of claims 1 to 8 , wherein the gel damper member has a penetration of 90 degrees to 110 degrees.

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