JPH06197570A - Ultrasonic motor with power increasing mechanism - Google Patents

Abstract

PURPOSE:To directly drive an ultrasonic motor in a power increased and low- speed condition without changing the size of a driving module utilizing a friction-transmission driving mechanism. CONSTITUTION:A transmission system is constituted in such a way that a driving roller 5 having a larger diameter is press-contacted with a direct-acting shaft and another driving roller 6 having a smaller diameter is directly coupled with the roller 5. Then a frame shaft 8 is press-contacted with the outside diameter section of the roller 6 as an output shaft. In addition, the rollers 5 and 6 are constituted so that they can have rigid properties in their rotating directions and required elastic functions in their diametral directions and the movement of the direct-acting shaft is transmitted by friction to the shaft (output shaft) 8 through the rollers 5 and 6 by giving pressing forces to the contact sections of the roller 5 and shaft 8 required for friction drive. The transmission system is increased in power and reduced in speed in proportion to the diametral ratio between the rollers 5 and 6 and united with an ultrasonic linear motor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear type ultrasonic motor which presses a drive module against a linear shaft to obtain a linear drive.

[0002]

2. Description of the Related Art FIG. 4 shows an example of a conventional linear type ultrasonic motor in which a drive module is arranged on a linear drive shaft to obtain a linear drive. FIG. 4 is a front view of an essential part showing an example of the ultrasonic motor, and FIG. 5 is a side view of FIG. 4, in which a drive module 1 ′ integrally constructed by using a piezoelectric element or the like is provided on a guide surface 11 of a linear motion shaft 11.
It is pressed against a and placed on it, fixed by mounting brackets 2 ′, and guide rollers 4 ′ are placed on both ends of the guide surface 11a to pivotally support the linear shaft 11 so that it can move only in the straight traveling direction. These are integrally constructed to form a linear ultrasonic motor. The driving operation of the ultrasonic motor configured as described above will be described. When the driving module 1 ′ is driven in the right direction, for example, in the right direction, a pulse for the right (for the right in FIG. 4) is pulsed. Drive module 1'if power is supplied
The counterclockwise elliptical wave motion is synthesized (not shown) on the lower surface of the pressing contact (A 'part in FIG. 4), and the linear shaft 11 pressing on this surface transmits the wave motion by friction force. It is driven straight ahead. Of course, in order to obtain driving in the left direction, the power supply for the right may be turned off and the power supply for the left may be supplied.

[0003]

However, in the above structure, the wave force and speed of the pressing surface of the drive module 1'are determined by the size of the drive module 1 '. That is, in order to increase the force, the area of the piezoelectric element must be increased, in order to reduce the speed, the wave system path must be long, and the driving wave number (it is necessary to resonate with longitudinal waves to obtain a large output). Because of) it is necessary to lower. The former becomes larger in the plane direction (area direction), the latter becomes larger in the vertical direction, and eventually the whole becomes larger. Therefore, theoretically, it is possible to obtain the desired high output and low speed,
Actually, if the piezoelectric element is enlarged, the piezoelectric characteristics (voltage → force
Distortion), processing accuracy, etc.
Since it requires a large mass and cannot be increased so much in practical use, the output and speed are ultimately limited. However, for example, when an extremely large force and a low-speed linear drive are required as a drive source for ultra-precision positioning of labor-saving equipment, machine tools, etc. However, the power is insufficient and the speed is too fast to be utilized, which is extremely problematic. The present invention was devised in view of the above-mentioned points, and an object thereof is to obtain a large direct power and an extremely low speed without changing the size (plane, vertical direction of the chair) of the drive module 1 '. As described above, the present invention provides a linear ultrasonic motor having a boosting mechanism.

[0004]

[Means for Solving the Problems] In other words, a means for achieving the object is a linear type ultrasonic motor in which a drive module is arranged on a linear motion shaft to obtain a linear drive, and is pressed against the linear motion shaft. A drive roller having a large diameter, and directly connected to it, a drive roller having a diameter smaller than that of the drive roller described above is arranged, and a frame shaft is arranged so as to be pressed against this outer diameter portion, and this is used as the output shaft. , The large and small drive rollers are rigid in the rotating direction and have a required elastic function in the radial direction,
A required pressing force necessary for friction drive is applied to each pressing portion, and the movement of the direct acting shaft is friction-transmitted to the frame shaft (output shaft) via the large and small driving rollers, and the large and small driving rollers. The transmission system is constructed by increasing and decelerating by the diameter ratio, and integrated as a linear ultrasonic motor.

[0005]

The operation will be described in detail in conjunction with the embodiment described below.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a front view of a main part of an embodiment of the present invention,
2 is a plan view in the direction of arrow A in FIG. 1, and FIG. 3 is a sectional view taken along the line E-I in FIG. 1. In FIGS. 1, 2, and 3, the drive module 1 is pressed against the upper guide surface 3a of the linear shaft 3. , Is fixed elastically by the mounting bracket 2. Further, each driving roller 5 having a large diameter is arranged on the upper and lower guide surfaces 3a of the linearly moving portion 3, and the linking shafts 7 are arranged on both sides by being directly connected to the driving roller 5, and the diameters of the driving rollers 5 having a larger diameter are arranged on both ends thereof. The drive roller 6 having a small diameter is arranged, the required diameter ratio is set so that this diameter ratio becomes the power increasing ratio, and the guide surface 8a of the frame shaft 8 is arranged on the outer diameter portion of each drive roller 6 having a small diameter. The linking shaft 7 is fixed by supporting a rotary shaft with a bearing 10. The structures of the large and small drive rollers 5 and 6 are assumed to be rigid in the rotating direction and have a required elastic function in the radial direction. The pressing force required for friction driving is applied to the guide surfaces 3a and 8a, and the frame shaft 8 has a substantially rectangular frame shape. The linear shaft 3 is arranged in the middle of the frame. Then, the guide surfaces 8a on both sides thereof are pivotally supported by the guide rollers 9 so that the frame shaft 8 can be linearly moved only in the longitudinal direction (horizontal direction in FIG. 1), and one end of the frame shaft 8 is connected to the output shaft. 8b, both ends of the guide surface 3a of the linear motion shaft 3 are pivotally supported by the guide rollers 4, and these are integrated to transmit the force from the drive module 1 to the linear motion shaft 3 to drive each large and small drive. It is configured to be transmitted to the rollers 5 and 6, and to be transmitted to the frame shaft 8 after being decelerated by an amount corresponding to this diameter ratio, so that linear drive can be obtained.

In this embodiment, the drive module 1 using a piezoelectric element is pressed against the linear drive shaft 3, but the drive module 1 is not limited to this, and the linear drive shaft 3 can be installed to drive the linear drive. Drive source such as electromagnetic type, air type, hydraulic type,
Of course, any of various linear type motors can be applied. Next, the driving operation of the ultrasonic motor with the power increasing mechanism configured as described above will be described.

When the driving module 1 is driven in the right direction, for example, in the right direction, a pulsed power source is supplied to the right side (the right side in FIG. 1), and the pressing lower surface of the driving module 1 (see FIG. 1A) is supplied. (Part) is composed of counterclockwise elliptical wave motions (not shown), and the linear axis 3 pressing against this surface
The wave motion moves straight by being transmitted by frictional force. Then, the drive roller 5 having a large diameter, which is pressed against the linear motion shaft 3 by applying the required elastic force, rotates, and the drive roller 6 directly connected thereto and having a small diameter also rotates. Further, the frame shaft 8 pressed against this also moves linearly by friction transmission in accordance with this rotation. Of course, the pressing force is set by applying a required elastic force so that the friction transmission force is greater than the direct drive force in each drive transmission system. The power transmission ratio of the linear drive shaft 3 and the frame shaft 3 (output shaft 8b) and the speed reduction ratio are constructed in accordance with the ratio of the diameter of the driving roller 5 and the diameter of the driving roller 6. If the diameter ratio between the diameter side and the small diameter side is set to 2: 1, the power increase is doubled and the deceleration is halved, so that straight drive can be obtained from the output shaft 8b.

[0009]

As described above, according to the present invention, the driving force can be increased and decelerated by the outer diameter ratio of the driving roller 5 having a large diameter and the driving roller 6 having a small diameter without changing the size of the driving module 1. Also in terms of size and mass, the weight is much smaller than that in the case where the drive module 1 is enlarged to obtain an equivalent output. Further, the purpose of increasing or decelerating the gear can be achieved by the gear reduction mechanism of the gear ← → rack instead of the driving rollers 5 and 6 having large and small friction transmissions. ,
It has great advantages such as ultra-precision positioning control because the response of the transmission system is fast, and it is extremely useful as a drive source for labor-saving equipment, machine tool feeding, robots, etc. Will be high.

[Brief description of drawings]

FIG. 1 is a front view of essential parts showing an embodiment of an ultrasonic motor with a power increasing mechanism according to the present invention.

FIG. 2 is a plan view in the direction of arrow A in FIG.

FIG. 3 is a sectional view taken along the line E-I of FIG.

FIG. 4 is a front view of a main part of a conventional ultrasonic motor.

FIG. 5 is a side view of FIG.

[Explanation of symbols]

 1 Drive Module 1'Drive Module 2 Mounting Bracket 2'Mounting Bracket 3 Linear Shaft 4 Guide Roller 4'Guide Roller 5 Drive Roller 6 Drive Roller 7 Linkage Shaft 8 Frame Shaft 9 Guide Roller 10 Bearing 11 Direct Drive Shaft 3a Guide Face 8a Guide surface 8b Output shaft 11a Guide surface

Claims (1)

[Claims] 1. In a linear type ultrasonic motor for driving a linear drive by arranging a drive module on the linear drive shaft, drive rollers each having a large diameter are arranged on the upper and lower guide surfaces of the linear drive shaft and are directly connected to this. The driving shafts with smaller diameters than the driving rollers at both ends, and set the required diameter ratio so that this diameter ratio is the boosting ratio. The guide surface of the frame shaft is arranged on the outer diameter portion of the roller, and the linking shaft is fixed by rotatably supporting the shaft with a bearing, and the structure of the drive rollers of large and small diameters has a property of being rigid in the rotation direction, It has a required elastic function in the radial direction, and is provided on the guide surface by applying a required pressing force required for frictional driving to the pressing portions of the driving rollers of different diameters. The structure of the is made into a substantially rectangular frame shape, the direct acting shaft is arranged in the middle part of the frame, and the guide surfaces on both sides of The inner roller is pivotally supported so that the frame shaft can be linearly moved only in the longitudinal direction, one end of the frame shaft is used as an output shaft, and both ends of the guide surface of the direct drive shaft are pivotally supported by the guide rollers. By integrating these, the force from the drive module is transmitted to the linear drive shaft, and further transmitted to each large and small drive roller, and the speed is increased and reduced by this diameter ratio and then transmitted to the frame shaft to obtain straight drive. An ultrasonic motor with a booster mechanism characterized by being configured as described above.