JP4883097B2 - Vibration type linear actuator - Google Patents

Description

  The present invention relates to a vibration type linear actuator that can be used as a drive source for a reciprocating electric shaver or the like.

  Conventionally, an electromagnetic core block having an electromagnet, a pair of movers that are provided with permanent magnets and a back yoke and are movably supported with respect to the electromagnetic core block, and a connecting spring portion that connects the pair of movers And a connecting body having a spring property for attaching the mover to the electromagnetic core block, while maintaining a constant gap between the magnetic pole surface of the electromagnet in the electromagnetic core block and the magnetic pole surface of the permanent magnet provided on the mover, A vibration type linear actuator is known in which the movable element is driven to reciprocate by an electric current supplied to an electromagnet in alternating directions (see, for example, Patent Document 1).

  FIGS. 9 to 11 show a partial configuration of an example of this type of vibration type linear actuator. FIG. 9A is a view from the inside when the actuator is cut vertically between two movers. FIG. 9B is a sectional view of the cut part, FIG. 10 is a plan view showing the structure when horizontally cut at the upper surface of the back yoke inserted into the two movers, and FIG. FIG. 11 is a diagram showing the configuration of the back yoke of the front (front side) mover and the back yoke of the rear (rear) mover, and FIG. 11 (a-1) is a plan view of the back yoke of the front mover. 11 (a-2) is a side view thereof, FIG. 11 (b-1) is a plan view of a back yoke of a rear movable element, and FIG. 11 (b-2) is a side view thereof.

  In FIG. 9, 101 is an electromagnetic core block, 102 is a mover, 107 is a rectangular plate-shaped permanent magnet, and 108 is a rectangular plate-shaped back yoke joined to the upper surface thereof. The pair of movers 102 and 102 are juxtaposed adjacent to each other in the front-rear direction of the vibration type linear actuator, and are supported so as to be movable in the left-right direction orthogonal to the juxtaposition direction. Each mover 102 is inserted into a fitting space 112a provided in a resin mover housing 112 on the outer side in the direction in which the movers 102 are juxtaposed [the opposite side of the paper surface of FIGS. 9 (a) and 9 (b). ] By inserting the back yokes 108 respectively.

  The electromagnetic core block 101 is configured by attaching an electromagnet 106 to a stator housing 111, and includes a stator housing 111, a mover housing 112, a connecting spring portion 113 that connects the pair of movers 102 and 102, and A connecting body 114 having a spring property for attaching the mover 102 to the electromagnetic core block 101 is constituted by an integrally formed block 110 made of synthetic resin.

  Further, as shown in FIG. 10, each of the front and rear back yokes 108F and 108R (108) has a magnetic circuit component 181 at the center in the moving direction (left-right direction) of the mover 102, and both sides thereof. The pair of arm portions 182 and 182 extend from the rear end to the front end in the insertion direction. The pair of arms 182 and 182 protrude forward in the insertion direction by the same dimension as the length of the magnetic circuit component 181, and the rear wall of the fitting space 112 a of the mover housing 112 has a tip of the arm 182. The through-hole 112b to enter is open.

  Further, the back yokes 108F and 108R (108) are inserted into the fitting spaces 112a of the mover housing 112 at appropriate positions of the magnetic circuit components 181 of the back yokes 108F and 108R (108). , 108R (108) are provided with screwing portions 183 for screwing the mover housing 12 and the back yokes 108F, 108R (108). In this case, the screwing 183 is formed on the substantially same surface as the upper surface of the magnetic circuit component 181 (fitting surface with respect to the fitting space 112a) or a surface that is recessed by one step.

JP 2005-354879 A

  By the way, in the conventional example shown in FIGS. 9 to 11, the through hole 112 b into which the tip of the arm portion 182 of the back yoke 108 enters is opened in the back wall of the fitting space 112 a of the mover housing 112. The rigidity of the mover housing 112 may be reduced. For this reason, the magnetic force (arrow Q in FIG. 9) of the permanent magnet 107 cannot be set large, and the thickness of the back yoke 108 must be increased to compensate for it. There was a problem that it was difficult to realize downsizing.

  In view of the above circumstances, an object of the present invention is to provide a vibration type linear actuator that can reduce the thickness of a back yoke, and thereby can reduce the size of the mover and the entire actuator.

  In order to solve the above-mentioned problems, the invention of claim 1 includes a permanent magnet, which has a rectangular plate shape, and a back yoke integrally coupled to the permanent magnet, and is arranged adjacent to each other. And a pair of movers supported so as to be movable in a direction orthogonal to the juxtaposed direction, an electromagnetic core block provided with an electromagnet and arranged to face the movers via a gap, and the pair of pairs A connecting spring portion for connecting the movers to each other; and a connecting body having a spring property for connecting the movers to the electromagnetic core block in a movable state, and each of the movers is made of resin. The back yoke is configured to be inserted into a fitting space provided in the mover housing from the outside in the direction in which the movers are arranged side by side, and each back yoke has a central portion in the moving direction of the mover. To magnetic circuit And a pair of arms extending from the rear end to the front end in the insertion direction on both sides thereof, and a permanent magnet provided on the magnetic pole surface of the electromagnet in the electromagnetic core block and the mover In a vibration type linear actuator in which the movable element is reciprocally driven by a current supplied in an alternating direction to the electromagnet while maintaining a constant gap with the magnetic pole surface of the movable element housing, a fitting space of the movable element housing is inserted. An opposite wall facing the tip of the arm portion is provided at the back end in the direction.

  A second aspect of the present invention is the vibration type linear actuator according to the first aspect, wherein the length of the arm portion in the insertion direction of the back yoke is shorter than the length of the magnetic circuit constituent portion. Yes.

  The invention according to claim 3 is the vibration type linear actuator according to claim 1 or 2, wherein the back yoke is provided with a screwing portion having a screw hole penetrating in the thickness direction thereof. The stop part protrudes in the convex shape from the fitting surface with respect to the fitting space of the said needle | mover housing of the said magnetic circuit structure part.

  The invention according to claim 4 is the vibration type linear actuator according to any one of claims 1 to 3, wherein the weight balance of the back yoke is set to the rear end side in the insertion direction of the back yoke. It is characterized in that a weight block part is provided for movement.

  According to the first aspect of the present invention, the opposing wall facing the tip of the arm portion of the back yoke is provided at the back end in the insertion direction of the fitting space of the mover housing. Since the hole is closed by the wall, the rigidity of the mover housing can be increased. Therefore, as the rigidity of the mover housing increases, the permanent magnet can be enlarged to increase the magnetic force with the electromagnet. As a result, the back yoke can be made thinner and the actuator can be made smaller. Become.

  According to the second aspect of the present invention, since the arm portion of the back yoke is shortened, the armature housing is provided with an opposing wall facing the tip of the arm portion while increasing the length of the magnetic circuit component. It becomes possible.

  According to the invention of claim 3, the thickness of the screwing portion is increased while realizing a reduction in the thickness of the magnetic circuit constituting portion of the back yoke, so that a sufficient screw allowance for fixing the back yoke to the mover housing is obtained. Can be easily secured. In other words, in the past, since the screw fixing portion was formed on the substantially same surface as the fitting surface or the one-step recessed surface, the entire thickness of the magnetic circuit component portion was increased from the viewpoint of securing the screw margin. However, by increasing the thickness of only the screwing portion, it is possible to reduce the thickness of the entire magnetic circuit component of the back yoke.

  According to invention of Claim 4, there can exist the following effect. That is, when a driver element extending to the other movable element side connected in parallel is connected to each movable element, the weight balance of each movable element is shifted to the other movable element side, and a rotational moment is applied to the movable element. However, by providing a weight block at the rear end of the back yoke, the deviation of the weight balance can be corrected (center of gravity adjustment), so the rotational moment can be relaxed,

It is the perspective view seen from the vibration type linear actuator of the embodiment of the present invention. It is the perspective view seen from the bottom of the vibration type linear actuator. It is the side view seen from the rear side of the vibration type linear actuator. It is the side view seen from the left-right direction of the vibration type linear actuator. It is a horizontal sectional view of the part which inserted the back yoke of the vibration type linear actuator. FIG. 10 is a diagram for comparing the vibration type linear actuator of the embodiment of the present invention with the conventional example of FIG. 9, and (a) shows a configuration viewed from the inside when the actuator is cut vertically between two movers. A perspective view and (b) are sectional views of the cut portion. FIG. 6 is a diagram showing the configuration of a back yoke of a front (front side) mover and a back yoke of a rear (rear side) mover in the vibration type linear actuator, (a-1) is a back yoke of a front mover. (A-2) is a side view thereof, (b-1) is a plan view of a back yoke of a rear mover, and (b-2) is a side view thereof. It is a side view shown in order to demonstrate the relationship of the weight balance in the front-back direction of the vibration type linear actuator. A partial configuration of an example of a conventional vibration type linear actuator is shown, (a) is a perspective view showing a configuration viewed from the inside when the actuator is cut vertically between two movers, and (b) is a perspective view thereof. It is sectional drawing of the part cut | disconnected. In the same vibration type linear actuator, it is a top view which shows the structure at the time of cut | disconnecting horizontally by the upper surface of the back yoke each inserted in two movers. FIG. 7 is a diagram showing the configuration of a back yoke of a front (front side) mover and a back yoke of a rear (rear side) mover in the conventional vibration type linear actuator, (a-1) being a front mover. (A-2) is a side view thereof, (b-1) is a plan view of a back yoke of a rear movable element, and (b-2) is a side view thereof.

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

  1 is a perspective view of the vibration type linear actuator according to the embodiment as seen from above, FIG. 2 is a perspective view of the vibration type linear actuator as seen from below, and FIG. 3 is a side view as seen from the rear side of the vibration type linear actuator. 4 is a side view of the same vibration type linear actuator as viewed from the left and right, FIG. 5 is a horizontal sectional view of the portion where the back yoke of the same vibration type linear actuator is inserted, and FIG. FIG. 6 (a) is a perspective view showing a configuration viewed from the inside when the actuator is cut vertically between two movers, and FIG. 6 (b) is a view for comparison with a conventional example. FIG. 7 is a sectional view of a part, and FIG. 7 is a view showing the configuration of the back yoke of the front (front side) mover and the back yoke of the rear (rear side) of the vibration type linear actuator. 1) FIG. 7 (a-2) is a side view thereof, FIG. 7 (b-1) is a plan view of the back yoke of the rear mover, and FIG. 7 (b-2). These are the side views, and are side views shown for explaining the relationship of weight balance in the front-rear direction of the vibration type linear actuator. In each figure, F indicates the front side (front side), and R indicates the rear side (rear side).

  The vibration type linear actuator M is mounted as a driving source of a movable blade (inner blade) on the head portion of a reciprocating drive type electric razor. Is reciprocated in the left-right direction, whereby the hair that has entered the blade hole of the outer blade is cut by the cooperation of the inner blade and the outer blade.

  The blade portion provided in the head portion is provided with a plurality of outer blades (net outer blade and slit outer blade) arranged in the front-rear direction of the actuator, and inner blades are respectively provided corresponding to these outer blades, A driver is provided so that each inner blade can be driven. As shown in FIG. 8, the driving elements 5 and 5a are provided corresponding to the inner blades 51 and 52, and the driving elements 5c are also provided for use in the wrinkle.

  As shown in FIGS. 1 to 4, the vibration type linear actuator M includes a pair of movers 2 (2F, 2R) including a permanent magnet 7 and a back yoke 8, an electromagnet 6, and a gap. The electromagnetic core block 1 disposed opposite to the movable element 2 (2F, 2R), the connecting spring portion 14 that couples the pair of movable elements 2 (2F, 2R) to each other, and the movable element 2 (2F, 2R). ) Are connected to the electromagnetic core block 1 in a movable state, and have a plate-like coupling body 13 having a spring property, and the magnetic pole surface of the electromagnet 6 in the electromagnetic core block 1 and the mover 2 (2F, The movable element 2 (2F, 2R) can be reciprocated by supplying alternating current to the electromagnet 6 while maintaining a constant gap with the magnetic pole surface of the permanent magnet 7 provided in 2R). It is configured.

  Both the permanent magnet 7 and the back yoke 8 have a rectangular plate shape, and the back yoke 8 is integrally joined to the upper surface of the permanent magnet 7. The pair of movers 2 (2F, 2R) are arranged adjacent to each other in the front-rear direction (direction orthogonal to the vibration direction) of the actuator, and the left-right direction (vibration direction) orthogonal to the side-by-side direction (front-rear direction). ) Is supported in a movable state. The pair of movable elements 2 (2F, 2R) arranged side by side are integrally connected by a connecting spring portion 14. The connecting spring portion 14 has a spring property in the vibration direction (left-right direction) of the mover 2 (2F, 2R).

  The electromagnetic core block 1 is configured by attaching an electromagnet 106 composed of a core, a bobbin, and a coil to a resin-made stator housing 11, and the lower surface of the stator housing 11 is fixed to the casing of the head portion. It is fixed to the upper surface of the base 3.

  Further, each mover 2 (2F, 2R) is inserted into the fitting space 12a provided in the resin mover housing 12 from the outside in the direction in which the movers 2 (2F, 2R) are arranged in parallel. 4 and the back yoke 8 is inserted in the directions of arrows A and B in FIG. The lower wall of the fitting space 12a has an open central region so that the permanent magnet 7 can be exposed.

  As shown in FIGS. 5 and 7, the back yokes 8F and 8R (8) constituting the front and rear movable elements 2F and 2R (2) are moved in the moving direction of the movable elements 2F and 2R (2). A magnetic circuit component 81 having a large area is provided at the center in the (left-right direction), and a pair of arms 82, 82 extending from the rear end to the front end in the insertion direction (arrows A and B directions) on both sides thereof. have. The pair of arm portions 82 and 82 is shorter than the length of the magnetic circuit constituting portion 81 by the dimension t. As shown in FIG. 5 and FIG. An opposing wall 12b that faces the tip of the arm portion 82 is provided.

  In this case, the stator housing 11, the mover housing 12, the connecting spring portion 13 that connects the pair of movers 2 (2 F, 2 R), and the spring property for attaching the mover 2 to the electromagnetic core block 1. The connecting body 14 is composed of a synthetic resin integral molding block 10.

  In addition, as shown in FIG. 7, the back yokes 8F and 8R (8) are provided in the fitting space 12a of the mover housing 12 at appropriate positions of the magnetic circuit components 81 of the back yokes 8F and 8R (8). A screwing portion 83 for screwing the back yoke 8F, 8R (8) to the mover housing 12 and the back yoke 8F, 8R (8) in the inserted state is provided. In this case, the screwing 83 protrudes in a convex shape from the upper surface (fitting surface with respect to the fitting space) of the magnetic circuit component 81.

  Further, the rear end portion of each back yoke 8F, 8R (8) in the insertion direction (arrow A, B direction) is for moving the weight balance of each back yoke 8F, 8R (8) to the rear end side. A weight block portion 84 is provided.

  Each armature 2 (2F, 2R) is provided with an arm 15 so as to extend to the other armature side provided side by side, and the driver 5 is connected to each arm 15 so that the front side The driver 5 is connected to the rear movable element 2R, and the rear driver 5 is connected to the front movable element 2F.

  In this vibration type linear actuator, as shown in FIGS. 5 and 6, the opposing wall 12 b facing the tip of the arm portion 82 of the back yoke 8 is provided at the back end in the insertion direction of the fitting space 12 a of the mover housing 12. In other words, since the through hole 112b (see FIG. 9) into which the tip of the arm portion enters is closed with a wall, the rigidity of the mover housing 12 can be increased. Therefore, as the rigidity of the mover housing 12 increases, the permanent magnet 7 can be enlarged to increase the magnetic force between the electromagnet 6 (arrow Q in FIG. 6). As a result, the back yoke 8 is thin. Therefore, the actuator can be miniaturized.

  Further, by reducing the length of the arm portion 82 of the back yoke 8, the movable housing 12 is provided with an opposing wall 12b facing the tip of the arm portion 82 while increasing the length of the magnetic circuit component 81. Is possible.

  Further, since the screwing portion 83 of the back yoke 8 is formed in a convex shape, the back yoke 8 can be moved by increasing the thickness of the screwing portion 83 while realizing a reduction in thickness of the magnetic circuit component 81. Ensuring sufficient screw margin for fixing to the child housing 12 can be facilitated. In other words, in the past, since the screw fixing portion was formed on the substantially same surface as the fitting surface or the one-step recessed surface, the entire thickness of the magnetic circuit component portion was increased from the viewpoint of securing the screw margin. However, by increasing the thickness of only the screwing portion 83, the entire magnetic circuit constituting portion 81 of the back yoke 8 can be reduced in thickness, which can contribute to downsizing of the actuator.

  Further, since the weight block portion 84 is provided at the rear end of each back yoke 8, useless rotational moment acting on the mover 2 can be reduced. That is, as shown in FIG. 8, when the driving elements 5, 5a, 5c extending to the other movable element side connected in parallel are connected to the movable elements 2R, 2F, the weight of each movable element 2R, 2F. The balance will be shifted to the other mover side, and rotational moments A1 and A2 will act on the movers 2R and 2F, but by providing the weight block portion 84 at the rear end of the back yoke 8, The moments B1 and B2 in the opposite directions are generated, and the deviation of the weight balance can be corrected (center of gravity adjustment), so that the rotational moment can be relaxed.

  In the above embodiment, the case where the magnetic block 2 reciprocally vibrates with respect to the electromagnetic core block 1 is shown as an example. However, when the electromagnetic core block 1 reciprocates with respect to the magnetic block 2, or the electromagnetic core The present invention can also be applied to the case where both the block 1 and the magnetic block 2 vibrate reciprocally. A magnetic material piece may be provided instead of the permanent magnet.

DESCRIPTION OF SYMBOLS 1 Electromagnetic core block 2, 2F, 2R Movable element 6 Electromagnet 7 Permanent magnet 8, 8F, 8R Back yoke 12 Movable element housing 12a Fitting space 12b Opposite wall 13 Connection body 14 Connection spring part 81 Magnetic circuit structure part 82 Arm part 83 Screw fixing part

Claims (4)

Each of them has a rectangular plate-like permanent magnet and a back yoke integrally joined to the permanent magnet, and they are arranged adjacent to each other and movable in a direction perpendicular to the arrangement direction. A pair of supported movers;
An electromagnetic core block including an electromagnet and disposed to face the mover via a gap;
A connecting spring portion for connecting the pair of movers to each other;
A connecting body having a spring property for connecting the mover to the electromagnetic core block in a movable state;
Each of the movers is configured by inserting the back yoke from the outer side in the direction in which the movers are arranged in a fitting space provided in a resin-made mover housing,
Each back yoke has a magnetic circuit component at the center in the moving direction of the mover, and has a pair of arms extending from the rear end to the front end in the insertion direction on both sides thereof. ,
While maintaining a constant gap between the magnetic pole surface of the electromagnet in the electromagnetic core block and the magnetic pole surface of the permanent magnet provided on the mover, the mover is driven to reciprocate by the current supplied to the electromagnet in an alternating direction. In the vibration type linear actuator
A vibration type linear actuator characterized in that an opposing wall facing the tip of the arm portion is provided at the back end in the insertion direction of the fitting space of the mover housing. The vibration type linear actuator according to claim 1,
The vibration type linear actuator characterized in that the length of the arm portion in the insertion direction of the back yoke is shorter than the length of the magnetic circuit component. The vibration type linear actuator according to claim 1 or 2,
The back yoke is provided with a screwing portion having a screw hole penetrating in the thickness direction, and the screwing portion is formed from a fitting surface of the magnetic circuit component portion with respect to the fitting space of the mover housing. A vibration type linear actuator characterized by protruding in a convex shape. It is a vibration type linear actuator given in any 1 paragraph of Claims 1-3,
A vibration type linear actuator characterized in that a weight block portion for moving the weight balance of the back yoke to the rear end side is provided at the rear end portion in the insertion direction of the back yoke.

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