JPH0446253A - Actuator mechanism having displacement enlarging and power assisting function - Google Patents

Abstract

PURPOSE:To enable positioning highly accurately and finely for very small working and assembly by generating displacement and force on the output point for working through bending of a plurality of members due to drive energy from the outside. CONSTITUTION:A lever mechanism member 1 is composed of a rigid member 11 and a bimorph member 12 bendingly deforming, and the rigid member 11 is combined with a base through a rigid or an elastic joint. A member 2 is a bimorph member, and joined with the member 12 through an elastic joint 32. A working output point 4 is joined with a member 22 through an elastic joint 33. The member 1 is pushed with a cutout 13 as the input point of the rigid member 11 sideways, and received input displacement and force. Then the member 1 is worked as the lever mechanism supported with the combined part with the base, and displacement is laterally magnified at an elastic joint 31 part. This displacement is transmitted to the toggle mechanism member 12 and magnified in the second step. Further the bimorph members 12,22 are driven, and displacement, speed, and force are added to a tool 41.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to an actuator that performs work by generating minute displacements by bending the members themselves by driving energy applied to a plurality of members connected to each other. It is.

[Technical background of the invention and its problems] In electronics and precision equipment parts, miniaturization on the order of microns and submicrons and thinning of constituent materials are rapidly progressing. The production system for these parts requires minute and highly accurate movements. Currently, the processing machine most commonly used in the production of micro parts is a mechanical press, and in particular, what is called a high-speed precision press is used. In order to obtain high machining accuracy, it is necessary to improve the movement accuracy of the tool, but it is necessary to improve the movement accuracy of the arm that supports the tool, the positioning of the workpiece, the processing table that supports the lower part of the mold, and even more. Although the processing part is minute, the moving parts are large, so it is essential to increase the rigidity of the entire machine, which requires a large and sturdy main body. As a result, the cost of the machine is necessarily high, a large installation requires a large area, and most of the power required is used to operate the machine, with only a small amount needed for the job. In addition, there was a problem that the limit of the microscopic work that could be done was relatively large, and that there was not enough room left to perform microscopic work. The reason for this is that these machines were not originally created with the idea that the machines would perform minute tasks.

In order to solve the above-mentioned problem of minute work, it is necessary to develop a mechanism with a structure that allows for high precision and minute work, and whose main body is compact. The principle of its construction is shown in Fig. 1. The member 1 is a lever mechanism part that is connected to the base by a rigid or elastic joint and has no play.It receives input displacement and force at the input point 3 and is pushed from the side. Two members 0 and 1, which expand the displacement of the first stage, constitute a toggle mechanism unit connected with the member L by elastic joints, and expand the displacement of the second stage.

Break #sA is a stationary state before driving, and when input is input to input point 3, it becomes state BB. Further, member 1 and member 2 each constitute a member that actively deforms itself upon receiving drive energy, and the left and right four parts are driven independently. As a result, although the apparent rigidity is low, the bending deformation is suppressed under the reaction force of the output, resulting in state C, which increases the withstand load, and changes the output point's displacement, speed, and
The change characteristics of the generated force can be adjusted. This characteristic is the length and offset angle θ of the driving amount adjustment member 1.2.

It can be changed by θ2. By independently adjusting the amount of drive of the active members at four locations, it is possible to correct operations such as deviation or tilting of the axis of the output point 4. In addition, since the inertia can be reduced compared to conventional rigid members, high-speed response is improved, so in the operation of output point 4, residual vibrations that occur when acceleration increases are suppressed, and the accuracy of minute positioning is affected. It is easily possible to superimpose a vibration component on the operation of the output point 4 in order to reduce the frictional force.

[Purpose of the Invention] This invention eliminates bearings and uses elastic joints to eliminate friction and play in moving parts that cause deterioration of movement accuracy, so that actuators are suitable for small and high-precision tasks. . In addition, by eliminating the transmission-only mechanism, the transmission member itself serves as the driving part or a part of it, keeping the inertia of the moving part low and improving the responsiveness of the movement. This enables high precision and fine positioning for dense machining and assembly of minute parts.

[Summary of the Invention] The actuator mechanism of the present invention uses a lever mechanism to amplify input displacement in the first stage, and a toggle mechanism connected to the lever mechanism to amplify the input displacement in a second stage. In addition, the bimorph member formed in the lever and toggle mechanism is driven to generate a bending moment in the member itself, further increasing the displacement of the output point, increasing the force, making variable adjustments, and correcting deviations, tilting, etc. of the axis center. , it is possible to suppress residual vibrations or, conversely, to superimpose vibrations on motion.

[Embodiments of the Invention] The actuator mechanism of this invention will be explained with reference to FIGS. 2 and 3, which are drawings of embodiments.

Basically, an elastic gap formed by a pair of laminated piezoelectric elements 5, bimorph piezoelectric element members 12 and 22, an output part 4, a metal plate core material, and a notch part! Consisting of 7531.32.33. In order to eliminate the clearance required when installing the laminated piezoelectric element 5 and to apply a preload, when the support 71 is pushed with the push-in screw 6, the support part rotates around the notch as a fulcrum, and the laminated piezoelectric element Pressed to 5. The other support 72 that supports the laminated piezoelectric element 5 has a lever that forms a bimorph piezoelectric element! 5
! Groove member] Both ends of groove member 2 are embedded and fixed. The lever mechanism section 1 and the toggle mechanism section 2 share the same metal plate core material which is bent and formed into a prescribed shape symmetrical to the tool 41, and piezoelectric ceramic plates are attached to the front and back of each part of the core material. , bimorph type piezoelectric element members 12 and 22 are formed. A core material 33 between the output section 4 and the toggle mechanism member 22. The core member 32 between the toggle mechanism member 22 and the lever mechanism member 12 and the cutout portion 31 integrated with the base function as an elastic joint, and serve as direct opposites without backlash or friction.

The lever mechanism member 1 consists of a rigid member 11 and a bimorph member 12 that bends and deforms. are combined with.

The output point 4 that performs work is connected to the member 22 by an elastic joint 33, and the member 1 is pushed from the side by the notch 13, which is the input point of the rigid member 11, and receives input displacement and force. Then, it acts as a lever mechanism using the joint with the base as a fulcrum, and the elastic joint 31 is displaced and expanded in the lateral direction. This displacement is transmitted to the toggle mechanism member 12 to expand the displacement to the second stage. Furthermore, driving the bimorph members 12 and 22,
Adds displacement, speed, and force to the tool. At this time, tool 4
It is possible to detect the deflection or inclination of the axial center of the needle 1 from the relative positional relationship with the needle 81 fixed to the bottle 82, and to perform corrective driving.

〔Effect of the invention〕

The actuator mechanism according to the present invention is a laminated piezoelectric, and since the elongation caused by applying a voltage to the element 5 is too small, the displacement must be expanded, so the lever mechanism section 1 and the toggle mechanism section 2 are expanded in two steps. Then, a voltage is applied to the bimorph piezoelectric member formed on both types of structural parts to generate a bending moment and further bend the bimorph type piezoelectric member. A feature of the present invention is that this provides the effect of adding the following functions.

By driving the bimorph member, first, it is possible to increase the displacement, speed, and generated force of the output section, and to adjust the characteristics of the displacement, speed, and generated force of the output section relative to the displacement of the laminated piezoelectric element. Second, the bending stiffness of the member can be increased isometrically by driving, and the load capacity of the output point is increased not only by increasing the static bending stiffness due to the DC component of the applied voltage (but also by increasing the load capacity of the output point by the movement of the output point). In order to suppress the residual vibration that occurs, dynamic bending rigidity can be increased by superimposing an alternating current component on the applied voltage to interfere and cancel out the residual vibration.

Thirdly, by independently driving the bimorph members at 5.4 locations of the left and right laminated piezoelectric elements, it is possible to correct operational accuracy such as deviation and tilting of the axis of the tool in the output section. Fourthly, the bimorph member is excited and driven to resonate, and a vibration component is superimposed on the tool operation, thereby reducing the frictional force that affects the precision of minute positioning.

[Brief explanation of the drawing]

FIG. 1 is a diagram of the operating principle of an actuator mechanism according to the present invention, FIG. 2 is a longitudinal sectional view showing a structural example of the actuator mechanism according to the present invention, and FIG. 3 is a plan view thereof. ■...Lever mechanism part, 11...Rigid member, 12.22
... Bimorph member, 13... Notch, 2... Toggle mechanism section, 31.32.33... Elastic joint, 4...
・Output part, 41... Tool, 5... Laminated piezoelectric element,
6...Pushing screw, 71.72...Support, 81
. . . Needle, 82 . . . Bottle, A . . . Non-driving state, B . . . Driving state of only the input point, C . . . State 31 in which the driving of member 1.2 is added to the driving of the input point. Figure and

Claims (3)

[Claims] (1) A plurality of members constituting the lever and toggle mechanism, which are rigidly connected to each other or connected by joints with rotational elasticity, bend statically and dynamically by externally applied driving energy. An actuator that generates displacement and force at an output point attached to a member to perform work. (2) An actuator that performs minute work according to claim 1, which is used as a mechanism for expanding displacement by connecting the output point of the actuator that generates minute displacement to a member. (3) All or part of the material constituting the member is piezoelectric,
Patents that use functional materials that convert electromagnetic energy using electrostrictive or magnetostrictive materials, thermal energy using shape memory alloys, etc., or chemical energy using mechanochemical materials, etc. An actuator that performs minute work according to claim 1.