KR100269189B1 - Actuator for Positioning Mechanism - Google Patents

Abstract

An actuator for positioning mechanism is disclosed.

A through hole is formed at one side of the main frame, and an installation part is provided at an outer circumferential surface thereof; The movement member is positioned to maintain a predetermined gap with the tip of the main frame and is displaceable within the range of the gap; One end of the elastic member is inserted into the through hole and installed in the main frame, and the other end is installed in the movement member to relatively elastically bias the movement member and the main frame; The solenoid is installed in the installation portion of the main frame, by changing the elastic force of the elastic member by generating a magnetic field by the current applied from the outside to displace the moving member relative to the main frame; A damping means is provided between the main frame and the movement member to attenuate the displacement movement while supporting the movement member.

Therefore, the actuator can reduce the size of the apparatus because the micro displacement of the actuator driven at high speed can be determined within a predetermined gap range by using the principle of equilibrium / unbalance between the magnetic force of the solenoid and the elastic force of the elastic member. The fall of the response characteristic with respect to an electric current by miniaturization can be prevented.

Description

Actuator for Positioning Mechanism

The present invention relates to an actuator for a small / high speed positioning mechanism that requires fine adjustment, such as an optical device, for example. The resolution of the positioning mechanism is repeatedly driven at high speed within a micro displacement of about 50 μm or less. The present invention relates to an actuator for positioning mechanism that can increase accuracy, accuracy, and the like.

In general, an optical apparatus such as a CCD imager or the like has a two-axis positioning mechanism for moving the optical lens 2 on the XY plane so that light can be accurately irradiated onto an image element not shown, as shown in FIG. Prepared. This biaxial positioning mechanism is provided with an actuator 10 for adjusting the position of the optical lens 2 so that light emitted from a light source not shown can be accurately irradiated onto the image pickup device. The actuator 10 is formed by vertically overlapping the X-axis actuator 4 and the Y-axis actuator 6, which constitute two axes, respectively, and on the actuator 10, the movable table 8 on which the optical lens 2 is mounted is provided. Is installed.

Since the X-axis actuator 4 and the Y-axis actuator 6 should be compact because the two-axis positioning mechanism requires the necessity of precise control due to its characteristics, it is usually configured to exhibit electrical polarization by mechanical deformation from the outside. Piezo-electric elements are used.

However, the X and Y axis actuators 4 and 6 according to the prior art cannot obtain a large displacement because their driving distance is too limited, and in order to expand the movable displacement of the movable table 8, the piezoelectric The devices must be stacked in multiple layers. Therefore, the actuator 10 is enlarged, which hinders the demand for miniaturization of the device, which is a characteristic of the positioning mechanism.

The present invention was devised in view of the above problems, and the positioning mechanism has been improved in such a way that the moving member can be driven within a fine displacement at high speed by the balance / unbalance of the force between the magnetic force of the solenoid and the elastic force of the elastic member. The purpose is to provide an actuator for the purpose.

1 is a perspective view schematically showing an example of a conventional positioning mechanism actuator.

Figure 2 is an exploded perspective view schematically showing the main parts of the positioning mechanism actuator according to an embodiment of the present invention.

3 is a cross-sectional view of FIG.

4 is a bottom view schematically showing the bottom of the mainframe of FIG.

5 and 6 are a cross-sectional view and a bottom view schematically showing the movement member portion of FIG.

7 is a graph for explaining a correlation between the elastic force of the elastic member and the magnetic force of the solenoid in the actuator for positioning mechanism according to the present invention.

<Explanation of symbols for the main parts of the drawings>

20 ... main frame 22 ... through-hole 22a ... fixed

24 Mounting section 26 Mounting groove 28

29 Set screw 30 Movement member 32

34.Incision 36 ... Tightening groove 38 ... Settling groove

39.Retracting ring 40 ... Elastic member 42 ... Head

44 Elastic part 50 Solenoid 60 Attenuation means

70 ... Cover frame 72 ... V groove

Actuator for positioning mechanism according to the present invention for achieving the above object, the main frame provided on the outer circumferential surface centered on the through-hole formed on one side; A movement member positioned to maintain a predetermined gap with the front end of the main frame and installed to be displaceable within the range of the gap; An elastic member having one end inserted into the through hole and installed in the main frame, and the other end installed in the movement member, the elastic member relatively elastically biasing the movement member and the main frame; A solenoid installed on an installation portion of the main frame, the solenoid for displacing the moving member relative to the main frame by applying a change to the elastic force of the elastic member by generating a magnetic field by an electric current applied from the outside; And damping means installed between the main frame and the movement member to attenuate displacement movement of the movement member while supporting the movement member.

Here, the damping means is silicon filled in the V groove formed between one side of the main frame and the movement member, or further provided with a cover frame installed to surround the outside of the main frame, between the outer surface of the movement member and the cover frame It is preferable to be installed in the formed V groove.

On the other hand, according to another feature of the invention, the movement member is formed with two or more incisions radially around the coupling hole formed in the center so that it can be located coaxially with the through hole, the fastening groove is drawn in the outer peripheral surface It is preferable that the elastic member includes a shrinkage ring for bending the fastening groove in the state inserted into the coupling hole.

Another feature of the actuator according to the present invention, the mounting groove is formed on one side of the through hole of the main frame, the fixing piece mounted to the mounting groove so as to fix one end of the elastic member inserted into the through hole Preferably, the mainframe has a high permeability and is preferably low carbon steel or silicon steel without residual magnetic flux.

Furthermore, in the present invention, the range of the gap is determined to be three times the driving range to remove the nonlinearity of the displacement motion, and the elastic force (Fs) of the elastic member is within a range larger than the magnetic force (Fb) of the solenoid. The voltage is applied to the solenoid. Here, the elastic force (Fs) and the magnetic force (Fb) is calculated by the following equation.

Here, x represents the displacement of the moving member from the parallel state, k represents the elastic modulus, respectively.

On the other hand, in the present invention, it is preferable that the elastic member is a wire spring whose diameter is about 0.20 mm smaller than the diameter of the through hole.

Hereinafter, an actuator for a positioning mechanism according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is an exploded perspective view schematically showing an actuator for a positioning mechanism according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view of FIG.

2 and 3, the actuator of the present invention includes a main frame 20 in which a through hole 22 is formed, and a moving member positioned to maintain a tip and a predetermined gap G of the main frame 20. 30, the elastic member 40 inserted into the through hole 22 and installed on one side of the main frame 20, the solenoid 50 provided on the mounting portion 24 formed on the main frame 20, and the main A damping means 60 provided between the frame 20 and the movement member 30 and a cover frame 70 provided to surround the outside of the main frame 20.

The main frame 20 is a cylindrical member, it is preferable that the magnetic permeability is made of low carbon steel or silicon steel having a high permeability and no residual magnetic flux. The diameter of the through hole 22 formed in the center of the main frame 20 is preferably about 0.20 mm larger than the diameter of the elastic member 40. This is because it must be able to guide this during contraction / expansion of the elastic member 40. In addition, the fixing portion 22a is formed to extend from the through hole 22. The fixing portion 22a is a portion in which the elastic member 40 is pressed and fixed, and has the same diameter as the elastic member 40. Has

As shown in FIG. 4, a mounting groove 26 is provided at one side of the fixing portion 22a of the main frame 20, and a fixing piece 28 is installed in the mounting groove 26 to fix the fixing portion 22a. The fixing piece 28 is pressed to fix the elastic member 30 inserted in the. The fixing piece 28 is fixed by fastening means such as a set screw 29 or the like.

The cover frame 70 may be coupled to the outside of the main frame 20 to protect the main frame 20. The cover frame 70 is also manufactured using the same material as the main frame 20.

The movement member 30 is displaceable within the range of the gap G, and is installed to be connected to an optical lens of an optical device, not shown. Here, the range of the gap G is preferably determined to be three times the driving range of the actuator in order to prevent the nonlinear displacement movement of the actuator.

As shown in FIGS. 5 and 6, the movement member 30 has a coupling hole 32 formed at a center thereof so as to be coaxially located with the through hole 22. Two or more cutouts 34 are formed radially. The figure shows an example in which the cutout 34 is formed at an angle of 120 degrees. The cutout 34 is a space provided to compress the outer circumferential surface of the movement member 30 in a state where the elastic member 40 is inserted into the coupling hole 32. To this end, the movement member 30 has a fastening groove 36 is formed in the outer peripheral surface side. The fastening groove 36 is a space in which the shrink ring 39 is fastened, and is bent by using the shrink ring 39 in the fastening groove 36 while the elastic member 40 is inserted into the coupling hole 32. One end of the elastic member 40 is fixed to the coupling hole (32). On the other hand, it is formed to extend in the coupling hole 32, the seating groove 38 is formed is provided a space for the elastic member 40 can be coupled. One side of the movement member 30 is preferably a tab (not shown) is processed to mount the load.

The elastic member 40 includes a head portion 42 and the elastic portion 44. This head portion 42 is seated in the seating groove 38 of the movement member 30, one end of the elastic portion 44 is installed in the main frame 20. The elastic member 40 is a kind of wire spring. The thickness and length of the spring are such that the actuator can be driven within the gap G by the balance / unbalance of its own elastic force and the magnetic force of the solenoid to be described later. It is determined by the elastic modulus of k. On the other hand, the elastic member 40 provided between the main frame 20 and the movement member 30 is relative to the main frame 20, that is, the side facing the main frame 20 or the opposite side The elastic member 30 is elastically biased.

The solenoid 50 is used to displace the movement member 30 with respect to the main frame 20 by changing the elastic force of the elastic member 40 by generating a magnetic field by an electric current applied from the outside. The coil may be wound around the outer peripheral surface of the mounting portion 24 of the frame 20 by a predetermined number of times, or an electronically actuated electronic solenoid may be provided.

The damping means 60 is for attenuating the displacement movement of the movement member 30 while supporting the movement member 30. The damping means 60 includes silicon having excellent performances such as heat resistance, moisture resistance, etc., due to the displacement movement characteristics of the movement member 30. I use it. That is, the silicon is filled in the V groove 72 formed between one side of the main frame 20 or the cover frame 70 and the outer surface of the movement member 30.

Hereinafter, the assembly process of the actuator according to the present invention will be described.

First, the solenoid 50 is installed in the installation portion 24 of the main frame 20. Next, one end of the elastic portion 44 of the elastic member 40 is inserted into the seating groove 38 of the movement member 30 and the head 42 is seated in the seating groove 38. Subsequently, the contraction ring 39 is bent in the fastening groove 38 of the movement member 30 so that the gap of the cutout 34 is narrowed so that the coupling hole 32 of the movement member 30 shrinks. 40) is fixed to the movement member (30). In this state, one end of the elastic portion 44 of the elastic member 40 is inserted into the through hole 22 to reach the fixed portion 22a. Thereafter, after adjusting the desired gap G, the set screw 72 is fastened to fix one end of the elastic portion 44 by the fixing piece 26. Next, the cover frame 70 is fixed to the main frame 20, and then the silicon 70 is filled in the V groove 72 formed between the cover frame 70 and the movement member 30 to move the movement member 30. To be supported by the elastic member 40 and the damping means 70.

Referring to Figure 7 the operation of the actuator assembled as described above is as follows.

As shown, the elastic force (Fs) of the elastic member 40 has a negative slope by the thickness and length of the spring line, the elastic force (Fs) and the magnetic force (Fb) are respectively calculated by the following [Equation] Value. The displacement of the magnetic force Fb and the elastic force Fs in parallel, that is, in the parallel state, the movement member 30 is stopped. In this state, when a current is applied to the solenoid 50, a magnetic force Fb is generated to compress the elastic member 40. In this process, the magnetic force curve C1 is determined by the current flowing in the solenoid 50, and this current is determined by the applied voltage, so that the position of the magnetic force curve C1 can be determined by the applied voltage. For example, if the magnetic force curve C1 becomes high so as not to intersect the elastic curve C2 as in region A of FIG. 7, the gap G becomes zero unless current is removed, so that the movement member 30 is You cannot control the position. Therefore, the voltage applied to the solenoid 50 allows the magnetic force Fb of the solenoid 50 to be determined in a range smaller than the elastic force Fs of the elastic member 40. That is, the range of the voltage applied to the solenoid 50 is determined in the section (region B) where Fs> Fb.

On the other hand, when there is an external excitation force in the equilibrium state and the gap G becomes small, the reaction force due to the elastic force Fs of the elastic member 40 is greater than the magnetic force Fb, so that the movement member (G) increases. 30) is moved, on the contrary, when the gap G is increased by the external excitation force, the magnetic member Fb is larger than the elastic force Fs, so that the movement member 30 moves in the direction of decreasing the gap G. .

As a result, the actuator of the present invention is a structure that can control the position of the movement member 30 in accordance with the voltage applied by the process of moving the movement member 30 to the parallel to the disturbance. As described above, the gap G is determined to be three times the driving range in order to avoid nonlinearity of the actuator. Further, the time constant τ of the solenoid 50 represents an increase rate of the current according to the applied voltage, so it is preferable to make it as small as possible. This is because the maximum tracking speed of the current to the voltage for the high speed operation.

[Equation]

Here, x denotes the displacement from the parallel state of the moving member, and k denotes the elastic modulus, respectively.

As described above, the actuator for positioning mechanism according to the present invention can determine the fine displacement of the actuator driven at high speed within the range of the predetermined gap by using the principle of equilibrium / unbalance of the magnetic force of the solenoid and the elastic force of the elastic member. Therefore, the device can be miniaturized, and the degradation of the response characteristics with respect to the current due to the miniaturization can be prevented.

In addition, when setting the gap corresponding to three times the driving range of the actuator, it is possible to maximize the linear characteristics of the actuator.

Claims (10)

A main frame having an installation portion provided at an outer circumferential surface of the through hole formed at one side thereof; A movement member positioned to maintain a predetermined gap with the front end of the main frame and installed to be displaceable within the range of the gap; An elastic member having one end inserted into the through hole and installed in the main frame, and the other end installed in the movement member, the elastic member relatively elastically biasing the movement member and the main frame; A solenoid installed on an installation portion of the main frame, the solenoid for displacing the moving member relative to the main frame by applying a change to the elastic force of the elastic member by generating a magnetic field by an electric current applied from the outside; And And damping means provided between the main frame and the movement member to attenuate displacement movement of the movement member while supporting the movement member. The method of claim 1, The damping means is an actuator for positioning mechanism, characterized in that the silicon filled in the V groove formed between one side of the main frame and the movement member. According to claim 1, wherein the movement member is formed with two or more incisions radially around the coupling hole formed in the center so as to be located coaxially with the through hole, the outer peripheral surface is formed with a fastening groove is introduced, And a shrinkage ring for bending the fastening groove in a state in which an elastic member is inserted into the coupling hole. The method of claim 1, The mounting groove is formed on one side of the through-hole of the main frame, and having a fixing piece mounted to the mounting groove for fixing one end of the elastic member inserted into the through-hole Actuator. The method of claim 1, And a cover frame installed to surround the outside of the main frame, wherein the damping means is installed in a V groove formed between the outer surface of the moving member and the cover frame. The method of claim 1, The mainframe has a high permeability, actuator for positioning mechanism, characterized in that the low carbon steel or silicon steel without residual magnetic flux. The method of claim 1, The range of the gap is determined by three times the driving range to remove the non-linearity of the displacement movement actuator for a positioning mechanism. The method of claim 1, And the voltage is applied to the solenoid within a range in which the elastic force (Fs) of the elastic member is greater than the magnetic force (Fb) of the solenoid. The actuator for positioning mechanism according to claim 8, wherein the elastic force (Fs) and the magnetic force (Fb) are values calculated by the following equation. [Equation] Here, x represents the displacement of the moving member from the parallel state, k represents the elastic modulus, respectively. The method of claim 1, And the elastic member is a wire spring whose diameter is about 0.20 mm smaller than the diameter of the through hole.