KR100276792B1 - Inch Worm Motor - Google Patents

Abstract

The present invention relates to an inchworm-type motor, which reduces the manufacturing cost by providing a single power source for clamping a rotating body and a rotating power source, thereby providing an inchworm-type motor having a compact structure and having a rotational area of 360 °. The purpose is to provide an inch-worm type motor that extends beyond this

The present invention includes a cylindrical rotor mounted to rotate about a fixed axis; A belt mounted to be in close contact or spaced apart from the outer circumferential part while surrounding the outer circumferential part of the rotor; A pair of actuators for linear driving, which stretches in the longitudinal direction of the belt while supporting both ends of the belt with respect to the base to closely contact or space the belt to the outer circumference of the rotor; And voltage supply means for providing a control voltage to the pair of actuators to control the amount of expansion and contraction of the actuators. Here, the pair of actuators simultaneously inflates by one unit so that the belt is brought into close contact with the rotor, and in the state where the belt is in close contact with the rotor, one actuator is further inflated by one unit while the other actuator is in one unit. The rotor is rotated by one unit by shrinking and restoring by.

Description

Inch Worm Motor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor that is a power source, and more particularly to an inchworm type motor which is a kind of stepping motor.

In general, a motor is used in a device driven by its own power, such as peripherals, factory automation equipment, and industrial equipment. Generally, stepping motors, DC and AC servo motors, and hydraulic motors are mainly used.

Since the general motors need to add a separate braking device for accurate braking control, the structure is complicated to improve the precision of the motor. On the other hand, if a separate braking device is not added for a compact structure, the precision of the motor is deteriorated, and thus it cannot be used in a device requiring high precision, such as a semiconductor automation facility or a digital video displayer (DVD).

Here, the inchworm type motor refers to a kind of stepping motor that continuously generates a multi-stage rotation divided by a small amount as crawling by an inchworm. Such an inch worm type motor is described in US Patent No. 5,034,647 "Inchworm type driving mechanism". In addition, the article "Piezoelectric-driven turntable with high positioning", T. Tojo and K. Sugihara, Bull. Japan Soc. of Prec. Engg., Vol. 23, No. 1, 1989, describes an inch-worm type motor capable of high-precision position control.

The conventional inch worm type motor disclosed in the above-described US patent includes a rotating body separated into two parts, a plate-shaped first clamp for clamping a part of the rotating body, and a plate-shaped clamping part for clamping the other part of the rotating body. 2 clamps, a first power source for closely contacting the first clamp to the rotating body, a second power source for closely contacting the second clamp to the rotating body, a third power source for rotating the rotating body, the kinetic force of the first, second power source It consists of a plurality of power transmission elements for transmitting the first and second clamp and a plurality of power transmission elements for transmitting the kinetic force of the third power source to the rotating body.

In particular, the first clamp and the second clamp for clamping the rotating body include a pair of arms that simultaneously engage the upper and lower surfaces of the rotating body, wherein a first power source or a second power source is inserted between the pair of arms. do. That is, when the first power source to the second power source is driven to expand, the pair of arms rotates about the hinge to engage the rotating body simultaneously from above and below. As such, when the third power source is driven while the first clamp or the second clamp clamps the rotating body, the motor rotates while the rotating body rotates.

As mentioned above, the conventional inch-worm type motor has a thicker thickness of the entire motor because the clamp clamps the upper, lower and upper surfaces of the rotating body, and the power source for clamping the rotating body with the two clamps. Since the power source for rotating the rotating body must be provided separately, there is a problem in that the structure is complicated and the number of parts increases and the manufacturing cost increases. In addition, the inch worm type motor presented in the above paper has a problem that the rotation range is limited to 0 ° ~ 90 °.

Accordingly, the present invention has been made in order to solve the problems of the prior art as described above, by unifying the power source for clamping the rotating body and the power source for rotating, to provide an inch-worm type motor of a compact structure and reduced manufacturing cost Its purpose is to. In addition, another object of the present invention is to provide an inch-worm type motor in which the rotation region extends beyond 360 °.

1 is a perspective view showing an inch worm type motor according to an embodiment of the present invention,

2 (a) to 2 (a) are views illustrating a process in which the inch worm type motor shown in FIG. 1 rotates in a counterclockwise direction.

* Explanation of symbols for main parts of the drawings

11 base 12 fixed shaft

13: rotor 14: bearing

21: first belt 22: second belt

31: first piezoelectric element 32: first support pillar

33: first connecting rod 34: second piezoelectric element

35: second support pillar 36: second connecting rod

37: third piezoelectric element 38: third support pillar

39: third connecting rod 40: fourth piezoelectric element

41: fourth support pillar 42: fourth connecting rod

51 control device 52 high voltage amplifier

Inch worm type motor according to the present invention for achieving the above object, and a cylindrical rotor mounted to rotate about a fixed axis as a central axis;

A belt mounted to be in close contact or spaced apart from the outer circumferential part while surrounding the outer circumferential part of the rotor;

A pair of telescopic actuators provided on each end of the belt for linearly moving the ends of the belt,

The pair of actuators simultaneously expand by one unit to bring the belt into close contact with the rotor,

In the state in which the belt is in close contact with the rotor, one actuator is further inflated by one unit and the other actuator is contracted and restored by one unit to rotate the rotor by one unit.

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

1 is a configuration diagram showing an inch worm type motor according to an embodiment of the present invention, Figure 2 is a view showing an operation state diagram when the inch worm type motor shown in Figure 1 rotates in a counterclockwise direction. .

Referring to FIG. 1, an inch worm type motor according to the present invention includes a base 11, a fixed shaft 12 supported in a vertical direction to the base 11, and a rotation about the fixed shaft 12 as a central axis. The cylindrical rotor 13 and the bearing 14 inserted between the fixed shaft 12 and the cylindrical rotor 13, and the outer peripheral portion of the rotor 13, while being closely attached to the outer peripheral portion or It is mounted so as to be spaced apart and provided to each of the belt (21, 22) for providing a rotational force to the rotor 13 in a state in close contact with the outer peripheral portion, and the ends of the belt is linearly moved And a pair of flexible actuators, and a voltage supply means for providing a control voltage to the actuators to control the amount of expansion and contraction of the actuators.

In the above inch worm type motor, when the two belts 21 and 22 are mounted to each other at positions different from each other, the inch worm type motor can be obtained in which the rotational area of the motor can be infinitely extended and high precision braking control is possible. . At this time, if the two belts 21 and 22 are configured to have a phase difference of 180 °, a more accurate rotation angle of the motor can be obtained.

The actuator uses a piezoelectric element in which the amount of expansion and contraction varies according to the control voltage. That is, a first piezoelectric element 31 and a second piezoelectric element 34 are provided at both ends of the first belt 21, wherein the first piezoelectric element 31 and the second piezoelectric element 34 are first supported. It is supported with respect to the base 11 by the pillar 32 and the 2nd support pillar 35, respectively. The first piezoelectric element 31 and the first belt 21 are connected by the first connecting rod 33, and the second piezoelectric element 34 and the first belt 21 are connected by the second connecting rod 36. do.

In addition, a third piezoelectric element 37 and a fourth piezoelectric element 40 are connected to both ends of the second belt 22, and the third piezoelectric element 37 and the fourth piezoelectric element 40 are supported by a third support. It is supported with respect to the base 11 by the pillar 38 and the 4th support pillar 41, respectively. The third piezoelectric element 37 and the second belt 22 are connected by the third connecting rod 39, and the fourth piezoelectric element 40 and the second belt 22 are connected by the fourth connecting rod 42. do. In this case, the first and second connectors 33 and 36 and the third and fourth connectors 39 and 42 use elastic joints to amplify the displacement of the piezoelectric elements 31, 34, 37, and 40. It can be replaced by displacement amplifier.

The voltage supply means includes a control device 51 for outputting a control signal and a high voltage amplifier for amplifying the control signal supplied from the control device 51 and providing the piezoelectric elements 31, 34, 37, and 40 to each piezoelectric element 31. 52).

The operation and effects of the present invention configured as described above are as follows.

First, the control unit 51 outputs a control signal to the high voltage amplifier 52 by calculating the rotation direction and the rotation angle of the inch worm type motor. The high voltage amplifier 52 amplifies the control signal to a high voltage and then applies it to the first piezoelectric element 31 to the fourth piezoelectric element 40. The piezoelectric elements 31, 34, 37, and 40 are expanded in length by the voltage applied thereto, and are contracted to the initial state when the applied voltage is removed.

When the piezoelectric elements 31, 34, 37, and 40 are in an initial state, the first belt 21 and the second belt 22 are spaced apart from the rotor 13. When the sum of the expansion amounts of the first piezoelectric element 31 and the second piezoelectric element 34 is 2 units (2α), the first belt 21 is in close contact with the rotor 13 and the third piezoelectric element 37 When the fourth piezoelectric element 40 expands by 2 units (2α), the second belt 22 is in close contact with the rotor 13.

In this way, the rotor 13 can be rotated while the first belt 21 or the second belt 22 is in close contact with the rotor 13. For example, the first belt 21 is attached to the rotor 13. When the second piezoelectric element 34 is contracted while the first piezoelectric element 31 is expanded while being in close contact, the rotor 13 is rotated toward the first piezoelectric element 31 by the first belt 21. In addition, when the second piezoelectric element 34 is expanded while the first piezoelectric element 31 is contracted while the first belt 21 is in close contact with the rotor 13, the rotor 13 is the first belt 21. It rotates toward the 2nd piezoelectric element 34 by this.

When the fourth piezoelectric element 40 is contracted while expanding the third piezoelectric element 37 while the second belt 22 is in close contact with the rotor 13, the rotor 13 is rotated by the second belt. Rotate towards element 37. When the fourth piezoelectric element 40 is inflated while the second belt 22 is in close contact with the rotor 13 and the third piezoelectric element 37 is contracted, the rotor 13 is moved by the second belt 22. Rotate toward the fourth piezoelectric element 40.

In the inch-worm type motor according to the present invention, the rotor 13 is rotated by the first belt 21 and the rotor 13 is rotated by the second belt 22 as described above. It becomes possible to drive. That is, after the first belt 21 is in close contact with the rotor 13 to rotate the rotor 13, the second belt 22 is in close contact with the rotor 13, and the second belt 22 is in the rotor 13. After being in close contact with the first belt 21 is spaced apart from the rotor 13, the second belt 22 rotates the rotor (13). Then, after the first belt 21 is in close contact with the rotor 13, the second belt 22 is spaced apart from the rotor 13, and the rotor 13 is rotated by the first belt 21. When the above operation is repeated, the rotor 13 continuously rotates.

Thus, since one belt is always in close contact with the rotor 13 while the rotor 13 is rotated by the first belt 21 and the second belt 22, the rotor 13 is driven by an external force. It is always possible to obtain a highly accurate rotation angle without being affected.

Hereinafter, a process in which the inch worm type motor rotates counterclockwise will be described with reference to the operation state diagram of FIG. 2.

2A illustrates an initial state. In the initial state, since the first piezoelectric element 31 to the fourth piezoelectric element 40 are all in a contracted state, the first belt 21 and the second belt ( 22 are all spaced apart from the rotor 13. 2B illustrates a state in which the third piezoelectric element 37 and the fourth piezoelectric element 40 are inflated at a displacement of 1 unit (α) so that the second belt 22 is in close contact with the rotor 13. Illustrated. That is, the control signal output from the control device 51 is amplified by the high voltage amplifier 52, and then applied to the third piezoelectric element 37 and the fourth piezoelectric element 40, and the third and fourth piezoelectric elements. (37, 40) expands by one unit (α) displacement, whereby the second belt 22 is in close contact with the rotor 13.

2 (c) shows that the third piezoelectric element 37 is further inflated by one unit α and the fourth piezoelectric element 40 is contracted by one unit α and returned to its initial position. , The rotor 13 is rotated counterclockwise by the second belt (22). That is, the controller 51 causes the voltage applied to the third piezoelectric element 37 to be doubled so that the third piezoelectric element 37 expands by 2 units (2α) displacement, and the fourth piezoelectric element 40 The fourth piezoelectric element 40 is contracted by a displacement of 1 unit (α) to return to the initial position by removing the voltage applied thereto. The rotor 13 rotates counterclockwise because the third piezoelectric element 37 expands and the fourth piezoelectric element 40 expands and contracts while the second belt 22 is in close contact with the rotor 13. .

2 (d) shows a state in which the first belt 21 is in close contact with the rotor 13 by expanding the first piezoelectric element 31 and the second piezoelectric element 34 by a displacement of 1 unit (α). do. That is, when the control signal output from the control device 51 is amplified by the high voltage amplifier 52 and then applied to the first piezoelectric element 31 and the second piezoelectric element 34, the first piezoelectric element 31. And the second piezoelectric element 34 respectively expand by one unit (α) displacement, whereby the first belt 21 is in close contact with the rotor 13. At this time, both the first belt 21 and the second belt 22 are in close contact with the rotor 13.

FIG. 2E shows a state in which the third piezoelectric element 37 is returned to the initial position. That is, the control unit 51 removes the voltage applied to the third piezoelectric element 37, whereby the third piezoelectric element 37 contracts by 2 units (2α) displacement and returns to the initial position, and the second The belt 22 is in a state spaced apart from the rotor 13.

2 (b) shows that the first piezoelectric element 31 returns to the initial position and the second piezoelectric element 34 is further inflated by one unit (α) displacement, so that the rotor 13 has a first belt ( A state rotated counterclockwise by 21) is shown. That is, the controller 51 removes the voltage applied to the first piezoelectric element 31 so that the first piezoelectric element 31 contracts by one unit (α) displacement to return to the initial position, and the second piezoelectric element The second piezoelectric element 34 expands by a displacement of 2 units (2α) by doubling the voltage applied to the element 34. At this time, since the second piezoelectric element 34 expands and the first piezoelectric element 31 contracts while the first belt 21 is in close contact with the rotor 13, the rotor 13 rotates counterclockwise. .

In FIG. 2, the third piezoelectric element 37 and the fourth piezoelectric element 40 are each inflated by one unit (α) displacement so that the second belt 22 is in close contact with the rotor 13. Illustrated. At this time, both the first belt 21 and the second belt 22 are in close contact with the rotor 13.

2 (a) shows a state in which the second piezoelectric element 34 returns to the initial position. That is, the control unit 51 removes the voltage applied to the second piezoelectric element 34, whereby the second piezoelectric element 34 contracts by 2 units (2α) displacement and returns to the initial position, and the first The belt 21 is in a state spaced apart from the rotor 13. After performing the process of (a) as described above, if the steps of (c), (d), (e), (ba), (g), (a) are sequentially repeated, the rotor 13 is Rotate counterclockwise.

Next, when the inch-worm type motor rotates in the clockwise direction, after the first belt 21 is in close contact with the rotor 13, the first piezoelectric element 31 expands and the second piezoelectric element 34 contracts. This causes the rotor 13 to rotate clockwise by the first belt 21. Then, after the second belt 22 is in close contact with the rotor 13, the first belt 21 is spaced apart from the rotor 13. Thereafter, the fourth piezoelectric element 40 expands and the third piezoelectric element 37 contracts so that the rotor 13 is rotated clockwise by the second belt 22. Then, after the first belt 21 is in close contact with the rotor 13, the second belt 22 is spaced apart from the rotor 13. By repeating the above process, the rotor 13 rotates clockwise.

As described above, the present invention provides a simpler structure, reduced number of parts, and a more compact structure of an inch worm-type motor, because the belt unit is in close contact with the rotor and the power source for clamping and the power source for rotating the rotor are unified. And manufacturing cost is effective to reduce. In addition, since the two belts alternately repeat each other, the rotation region is extended to infinity, and the effect of enabling more precise rotation angle control without being influenced by external force is possible.

Claims (4)

A cylindrical rotor mounted to rotate about a fixed axis; A belt mounted to be in close contact or spaced apart from the outer circumferential part while surrounding the outer circumferential part of the rotor; A pair of telescopic actuators provided on each end of the belt for linearly moving the ends of the belt, The pair of actuators simultaneously expand by one unit to bring the belt into close contact with the rotor, And one actuator is further inflated by one unit while the belt is in close contact with the rotor, and the other actuator is contracted and restored by one unit to rotate the rotor by one unit. The method of claim 1, further comprising one belt and a pair of actuators configured identically to the belt and the pair of actuators, The first belt and the first pair of actuators are disposed to have a 180 ° retardation around the second belt and the second pair of actuators and the rotor, and the first belt and the second belt alternately move the rotor one unit. Inch worm type motor, characterized in that for each rotation. 3. The inch worm type motor according to claim 1 or 2, wherein the actuator is a piezoelectric element that expands or contracts according to whether a voltage is applied. 4. The inchworm type motor of claim 3, wherein a displacement amplifier for amplifying the displacement of the piezoelectric element is additionally included between the belt and the piezoelectric element.