JP2006272531A - Guide device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a guide device capable of removing abrasion powder without using compressed gas by a simple structure. <P>SOLUTION: This guide device includes: an ultrasonic motor having a vibrator making elliptic motion and a friction member for transmitting the elliptic motion of the vibrator; a mover 63 having an abutting surface abutting on the friction member and moved by the frictional driver of the friction member and the abutting surface; and an abrasion powder scattering preventing casing for covering the ultrasonic motor which has opposite surfaces opposite to the abutting surface on both sides of the ultrasonic motor, wherein a plurality of grooves are formed on the opposite surfaces, respectively, and the space between the abutting surface and the opposite surfaces and the shapes of the grooves are set so that the abrasive power is caught in the grooves with the movement of the mover 63. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a guide device that drives a movable body that performs linear motion and rotational motion by friction drive of an ultrasonic motor.

  The ultrasonic motor has a feature that the minimum amplitude is as small as nanometer order, positioning with high resolution is possible, and the driving force is larger than other electromagnetic motors of the same size. Taking advantage of this feature, it has been put to practical use mainly in a rotational motion system such as a lens zoom mechanism of a camera and a vibration alarm of a wristwatch, but recently it has also been applied to a linear motion system.

  FIG. 8 shows an example of a conventional guide device disclosed in Patent Document 1 in which an ultrasonic motor is used as a drive source for a movable body. As shown in FIG. 8, in this guide device, a stage 63 which is a movable body is provided on a base board 61 via a pair of guide members 62 such as a cross roller guide, and the stage 63 is linearly moved by an ultrasonic motor. It is designed to guide you.

  In this conventional guide device, a driving force transmission member 64 is provided on one side surface of the stage 63 in parallel with the guide member 62, and a linear scale is provided on the other side surface of the stage 63 in parallel with the driving force transmission member 64. 65 is installed. In addition, a measuring head 66 is provided at a position facing the linear scale 65 to constitute the position detecting means 67, and an ultrasonic motor 500 is provided at a position facing the driving force transmitting member 64, thereby providing an ultrasonic motor. The friction member 56 is in contact with the contact surface 64a of the driving force transmission member 64 perpendicularly.

  In the figure, 57 is a housing for accommodating the ultrasonic motor, 68 is a control unit for controlling the driving conditions of the stage 63 based on the position information obtained from the position detecting means 67, and 69 is output from the control unit 68. The driver outputs a command signal for driving the ultrasonic motor based on the received signal.

  FIG. 9 shows a cross section of an ultrasonic motor housed in a casing 57 used for this guide device. The ultrasonic motor 500 includes a vibrating body 55 held by four springs 58 in a casing. The vibrating body 55 is formed on almost the entire surface of the piezoelectric ceramic plate 52, electrode films 53 a, 53 b, 53 c, 53 d formed on one main surface of the piezoelectric ceramic plate 52, and the other main surface of the piezoelectric ceramic plate 52. And a common electrode film (not shown). The four divided electrode films 53a, 53b, 53c, and 53d formed on one main surface of the piezoelectric ceramic plate 52 are connected to the opposite electrode film 53a and the electrode film 53d, and the other pair. The electrode film 53b and the electrode film 53c located at the corner are connected. Further, a friction member 56 made of ceramics or glass is provided on one end face of the vibrating body 55.

  In the ultrasonic motor configured as described above, when the common electrode film is grounded and voltages having different phases are applied to the electrode film 53b and the electrode film 53d, longitudinal vibration and lateral vibration are generated in the piezoelectric ceramic plate 52. The friction member 56 is elliptically moved by the resultant force of these vibrations.

  In addition, the ultrasonic motor 500 has both sides of the casing 57 held by springs 58, but a spring 59 is provided on the end surface opposite to the side where the friction member is provided. The vibration body 55 is pressed by the spring 59 and pressed against a driving force transmission member 64 provided on the stage 63 to apply a preload.

  The guide device disclosed in Patent Document 1 is configured as described above. When the ultrasonic motor 500 is driven, the stage 63 can be moved along the guide member 62 by the friction drive of the friction member 56. The control unit 68 can perform, for example, PID calculation processing based on parameters that change according to the deviation between the position information from the position detection unit 67 accompanying the movement of the stage 63 and the preset reference position information of the stage 63. The stage 63 is moved and positioned by performing feedback control for outputting a command signal to the ultrasonic motor 51 to the driver 69.

  However, there is a problem that the friction member 56 of the ultrasonic motor 500 and the driving force transmission member 64 of the stage 63 are worn away, and the wear powder adheres to the contact surface 64 a of the driving force transmission member 64. When this amount of adhesion increases, the wear powder scatters to the surroundings due to the vibration of the friction member 56, or the wear powder accumulated on the base board 61 scatters to the surroundings due to the vibration when the stage 63 moves, so the surrounding atmosphere is reduced. There was a problem of contamination. In particular, an apparatus in which the amount of dust adhering to the wafer is limited, such as a semiconductor manufacturing apparatus, is a serious problem.

In order to solve the above problem, Patent Document 1 discloses that a wear powder removing pad having a compressed gas injection hole and an exhaust groove is provided in a wear powder scattering prevention housing.
JP 2003-251541 A

  However, since the method disclosed in Patent Document 1 uses compressed gas, in order to use it in a vacuum, it is necessary to perform differential exhaust so that the compressed air does not leak into the vacuum. There are problems that it is additionally required, that the abrasion powder removing pad is very large, and that the positioning accuracy of the stage is deteriorated because the piping for differential exhaust is routed.

  Then, an object of this invention is to provide the guide apparatus which can remove an abrasion powder with a simple structure, without using compressed gas.

In order to achieve the above object, a guide device according to the present invention has an ultrasonic motor having an oscillating body that moves elliptically and a friction member that transmits the elliptical motion of the oscillating body, and the friction member. A movable body having a contact surface that comes into contact with the friction member and the contact surface so as to be movable by friction driving, and opposing surfaces facing the contact surface are provided on both sides of the ultrasonic motor. A guide device including a casing for preventing abrasion powder covering the ultrasonic motor,
A plurality of grooves are formed on each of the facing surfaces, and the distance between the contact surface and the facing surface and the shape of the grooves are set so that wear powder is captured in the grooves as the movable body moves. It is characterized by that.

  In the above guide device according to the present invention, a plurality of grooves are formed on the facing surface, and the gap between the contact surface and the facing surface and the shape of the groove are worn on the grooves as the movable body moves. Since the powder is set to be captured, it is possible to provide a guide device capable of removing the wear powder with a simple structure without using compressed gas.

  Hereinafter, embodiments of the present invention will be described. In the drawings of the embodiment, the same parts as those in the conventional example are denoted by the same reference numerals.

  FIG. 1 is a guide device according to an embodiment of the present invention, and uses an ultrasonic motor as a drive source of a movable body. 2A is a plan view showing the stage 63 and the ultrasonic motor portion in the guide apparatus of FIG. 1, and the wear powder scattering prevention cover 5 is shown so that the configuration of the wear powder removing means in the guide apparatus of the present invention can be understood. The upper surface is removed. Moreover, FIG. 2B is sectional drawing about the AA line of FIG. 2A. In FIG. 2A, the ultrasonic motor portion is shown in a sectional view.

As shown in FIG. 1 and the like, the guide device of this embodiment includes a pair of guide members 62 such as cross roller guides on a base board 61 as in the conventional example, and a stage as a movable body by these guide members 62. 63 is linearly guided so as to be able to reciprocate.
Further, the stage 63 has a driving force transmission member 64 attached to one side of the stage 63 in parallel with the guide member 62, and a linear scale 65 parallel to the driving force transmission member 64 on the other side of the stage 63. Respectively. A measuring head 66 is provided at a position facing the linear scale 65 to constitute a position detecting means 67, and one ultrasonic motor (not shown) is disposed at a position facing the driving force transmitting member 64. In addition, the friction member 56 of the ultrasonic motor 500 is brought into contact with the contact surface of the driving force transmission member 64 perpendicularly.

In the figure, 68 is a control unit for controlling the driving conditions of the stage 63 based on the position information obtained from the position detecting means 67, and 69 is for driving the ultrasonic motor based on the signal output from the control unit 68. A driver 5 outputs a command signal for causing the wear powder scattering prevention cover 5 to accommodate the wear powder scattering prevention casing 1 for preventing the wear powder scattering generated by the ultrasonic motor 500 from scattering. Reference numeral 3 denotes a base for fixing an electrostatic adsorption sheet that adsorbs wear powder.
Further, the structure of the ultrasonic motor and the attachment structure of the ultrasonic motor shown in FIG. 1 are the same as those shown in FIG. 8 and FIG.

Hereinafter, the details of the abrasion powder scattering prevention mechanism, which is a characteristic part of the present invention, will be described with reference to FIGS. 2A and 2B.
First, in the guide device of the present embodiment, the abrasion powder scattering prevention casing 1 shown in FIG. 3A and the like covers the ultrasonic motor 500 and wear between the driving force transmission member 64 and the ultrasonic motor 500. The powder is not scattered around.

  Here, in particular, in this embodiment, the housing 1 for preventing wear powder scattering has wear powder collecting grooves 2 a and 2 b on both sides of the ultrasonic motor 500 on the facing surface facing the driving force transmission member 64. The distance between the facing surface and the contact surface of the driving force transmission member 64 and the shape of the wear powder collecting grooves 2a and 2b are changed according to the movement of the stage (movable body). It is set to be captured to effectively prevent the scattering of wear powder.

That is, the present invention
(1) The distance between the facing surface of the casing 1 for preventing abrasion powder scattering and the contact surface of the driving force transmission member 64;
(2) The shape of the wear powder collecting grooves 2a, 2b provided on both sides of the ultrasonic motor 500 is
When set to an appropriate range,
Due to the movement of the stage (movable body), the relative movement of the facing surface of the casing 1 for preventing wear powder scattering and the contact surface of the driving force transmission member 64 is
The present invention has been completed by finding that the wear powder can be effectively captured in the wear powder collecting grooves 2a and 2b without using compressed air or a suction mechanism.
It is preferable that the wear powder collecting grooves 2a and 2b have a longitudinal direction substantially orthogonal to the moving direction of the movable body.
This is because the wear powder scattered in the longitudinal direction of the wear powder causes irregular reflection in the wear powder collecting grooves 2a and 2b if the angle formed by the trajectory drawn by the movable body and the grooves 2a and 2b is 90 °. Abrasive powder collecting effect is sufficiently generated.
Here, the movement direction of the wear powder collecting grooves 2a and 2b is substantially orthogonal means a range where the trajectory drawn by the movement of the movable body and the grooves 2a and 2b is 90 ° ± 20 °. Furthermore, the angle is more preferably 90 ° ± 2 °.
Further, the wear powder collecting grooves 2a and 2b are preferably parallel to each other. This is because, if there is only one wear powder collecting groove 2a, 2b on one side, the scattering speed of the wear powder is hardly attenuated, so that the wear powder jumps out of the wear powder collecting grooves 2a, 2b. Then, since the scattering speed of the wear powder is attenuated by the irregular reflection of the wear powder twice, the wear powder collecting effect is sufficiently generated.

  In the present invention, in order to more effectively capture the wear powder in the wear powder collecting grooves 2a and 2b, the surface (contact surface) of the driving force transmitting member 64 and the wear powder scattering prevention casing 1 opposed thereto are arranged. The distance T between the opposing surfaces is preferably 10 to 300 μm. This point is significantly different from the configuration of Patent Document 1 in which the distance is set in the range of 0.5 to 10 μm.

  This is because, in the configuration according to the present invention, if the distance T between the two is less than 10 μm, in the configuration according to the present invention in which compressed air or a suction mechanism is not used, the abrasion powder is worn on the contact surface of the driving force transmission member 64. This is because it becomes easy to bite into the gap with the powder scattering prevention casing 1. That is, according to the present invention, the wear powder collecting groove 2a, the relative movement between the facing surface of the wear powder scattering prevention casing 1 and the contact surface of the driving force transmission member 64 accompanying the movement of the stage (movable body). Since the wear powder is captured in 2b, it is preferable that the wear powder is three-dimensionally moved between the facing surface of the housing 1 for preventing wear powder scattering and the contact surface of the driving force transmission member 64. This seems to be because a wider interval is required compared to the configuration of Patent Document 1.

  On the other hand, if the distance T exceeds 300 μm, the distance from the contact surface 64a of the driving force transmission member 64 to the housing 1 for preventing wear powder scattering is too far away, so that the scattered wear powder is scattered around the environment. This is because the contamination of the stage 63 and the engagement with the guide member 62 of the stage 63 adversely affects the movement accuracy of the stage 63. Furthermore, the distance T is more preferably 10 to 100 μm.

  In addition, the material of the casing 1 for preventing abrasion powder scattering is preferably a metal such as an aluminum alloy or a stainless alloy that does not resonate with the vibration of the ultrasonic motor 500 or a ceramic such as alumina or zirconia.

  Moreover, it is preferable to set the depth and width of each of the wear powder collecting grooves 2a and 2b of the housing 1 for preventing wear powder scattering to be in the range of 1 to 5 mm. That is, if the depth and width are less than 1 mm or more than 5 mm, the efficiency of capturing the wear powder in the wear powder collecting grooves 2a and 2b is lowered. Outside this range, irregular reflection of wear powder does not occur, and the amount discharged from the gap tends to increase. Further, if there is only one wear powder collecting groove 2a, 2b on one side, the wear powder capturing efficiency is poor, and it is preferable to provide two or more wear powder collecting grooves on one side.

  Thus, according to the present invention, the distance between the surface (abutment surface) of the driving force transmission member 64 and the opposed surface of the abrasion powder scattering prevention casing 1 facing it is determined between the abutment surface and the opposed surface. It is set so as to move while repeating the reflection, and the wear powder is irregularly reflected on the inner walls of the wear powder collecting grooves 2a and 2b to be trapped and trapped in the wear powder collecting grooves 2a and 2b.

  Therefore, in the present invention, for example, as shown in FIG. 4, the opening width of the wear powder collecting grooves 2 a and 2 b is set so as not to release the wear powder captured in the wear powder collecting grooves 2 a and 2 b to the outside of the groove. It is preferable to make it narrower than the internal maximum width. In this way, the angle formed between the side wall of the groove and the facing surface becomes an acute angle, and the wear powder captured in the wear powder collecting grooves 2a and 2b can be hardly released to the outside of the groove. In addition, as shown in FIG. 4, when the width at the bottom of the wear powder collecting grooves 2a and 2b is set to the maximum width, the probability that the wear powder reflected by the side wall of the groove is reflected toward the inside of the groove increases. More effectively, the captured wear powder can be prevented from being discharged outside the groove.

  Further, in the guide device of the present embodiment, the wear powder scattering prevention cover 5 is provided to more reliably prevent the wear powder from scattering to the outside. That is, in this embodiment, since the abrasion powder scattering prevention housing 1 has a slight gap between the contact surface of the driving force transmission member 64, the abrasion powder collection grooves 2a and 2b are completely disposed. Can not stop the discharge of wear powder. Therefore, the abrasion powder scattering prevention cover 5 surrounding the abrasion powder scattering prevention casing 1 is attached to the driving force transmission member 64.

The wear powder scattering prevention cover 5 is attached so that there is no gap between it and the driving force transmission member 64, and the electrostatic adsorption sheets 4 a and 4 b on the base 3 are provided with a gap of 10 to 500 μm. I try not to. The wear powder scattering prevention cover 5 attached in this way moves together with the stage 63 and receives the abrasion powder that has jumped out of the abrasion powder scattering prevention casing 1 on the inner side of the upper surface and the side surface of the abrasion powder scattering prevention cover 5. 3, and is adsorbed by electrostatic adsorption sheets 4 a and 4 b (to be described later) provided on the base 3 to prevent the fallen wear powder from directly scattering around.
The wear powder scattering prevention cover 5 is preferably made of a metal such as an aluminum alloy or a stainless alloy that does not resonate with the vibration of the ultrasonic motor 500 or a ceramic such as alumina or zirconia.

  Furthermore, the guide device according to the present embodiment includes electrostatic adsorption sheets 4a and 4b as shown in FIGS. 3A and 3B. 3A is a top view, and FIG. 3B is a cross-sectional view taken along line BB in FIG. 3A. In the guide device of the present embodiment, as shown in FIG. 3A, when the stage 63 is moved to the right side with respect to the ultrasonic motor, the wear powder scattering prevention cover 5 moves together, so that the surface of the base 3 is exposed. On the other hand, the base 3a is exposed even if it moves to the left. Therefore, when the surface of the base 3 is exposed, if there are no electrostatic attraction sheets 4a and 4b, the wear powder adhering to the base 3 is floated again by the vibration when the stage 63 is moved to contaminate the surroundings. . Even if it is not exposed, the abrasion powder is slightly discharged also from the gap between the abrasion powder scattering prevention cover 5 and the base 3.

  Therefore, in the guide device of the present embodiment, electrostatic adsorption sheets 4a and 4b are provided in order to completely prevent wear powder from floating and discharging. In the present embodiment, the electrostatic adsorption sheets 4a and 4b have a structure in which two comb-shaped aluminum electrodes are alternately arranged and sandwiched between, for example, 50 μm polyimide resin. With the above structure, a voltage of -1 kV to -5 kV is applied between the two comb-like aluminum electrodes to generate static electricity on the surface to adsorb the wear powder. For example, a voltage of −1 kV to −5 kV is applied to one of the aluminum electrodes, and the other is grounded to the ground. By providing such electrostatic adsorption sheets 4a and 4b, the amount of scattering to the surroundings can be greatly reduced even if the stage 63 moves. In the present invention, the structure of the electrostatically adsorbing sheets 4a and 4b is not limited to such a structure, and any structure that can adsorb the wear powder may be used.

As described above, in the present embodiment, the guide device in which the movable body moves linearly has been described as an example. However, it goes without saying that the present invention can be applied to a guide device in which the movable body rotates, and further, an ultrasonic motor that drives the movable body. In addition, the present invention is not limited to the multi-mode type, and may be a single-vibration mode standing wave type or traveling wave, a multi-vibration mode mode conversion type, or a composite vibration type ultrasonic motor.
Thus, it goes without saying that the present invention can be applied to various improvements and modifications as long as they do not depart from the gist of the present invention.

Examples according to the present invention will be described below.
Example 1
In this embodiment, the wear powder scattering prevention housing 1 and the wear powder scattering prevention cover 5 of FIG. 2 and the guide device of the present invention shown in FIG. 1 provided with the electrostatic adsorption sheets 4a and 4b, and the wear powder scattering of FIG. A conventional guide device not provided with a prevention housing was prepared, and the amount of wear powder adhering to the upper surface portion of the stage 63 after moving the stage 63 of each guide device for 10 hours was compared.
In this example and the conventional example, the specifications of the guide device used for the experiment were as follows.
A cross roller guide having a stroke of 100 mm was used as the guide member 62 constituting the guide device, and the stage 63 having a weight of 5 kg was moved by the guide member 62. A driving force transmission member 64 made of alumina ceramic is disposed on one side surface of the stage 63, and the surface roughness of the contact surface 64a with the ultrasonic motor 51 is 0.05 μm in terms of arithmetic average roughness (Ra). did.

On the other hand, the ultrasonic motor 51 that is a drive source of the stage 63 is formed by forming a vibrating body 55 by a lead zirconate titanate-based piezoelectric ceramic body 52 that is a rectangular parallelepiped having a length of 30 mm, a width of 7.5 mm, and a thickness of 3 mm. A material obtained by joining a friction member 56 made of alumina ceramic having a length of 4.2 mm and a diameter of 3 mm to the end face of the vibrating body 55 was used. The contact surface of the friction member 56 with the driving force transmission member 64 was a spherical surface with a radius of curvature of 7 mm.

  The applied voltage to the electrostatic chucking sheets 4a and 4b used in the guide device of the present invention was set to -2 kV. In addition, in the case of only the wear powder scattering prevention casing 1 (data 1), the wear powder scattering prevention casing 1 and the wear powder scattering prevention cover 5 (data 2), the wear powder scattering prevention casing 1 and the wear powder scattering prevention cover. 5 and three types of experiments were performed when voltage was applied to the electrostatic adsorption sheets 4a and 4b (data 3).

In the experiment, as the movement profile of the stage 63 set in advance in the control unit 18, the trapezoidal control is set such that the movement distance is 100 mm, the acceleration / deceleration is 0.03 G, and the maximum speed is 100 mm / sec, and the ultrasonic motor 51 is driven at 40 kHz. Driven at frequency.
A sample for wear powder measurement (100 mm × 100 mm) is set on the stage 63, the stage 63 is driven for 10 hours under the above conditions, and the particle size of 1 μm or more adhered to the sample surface for wear powder measurement after the running test. The amount of wear powder was detected with an optical microscope (2000 magnifications) set on a stage. The result is shown in FIG.

  As a result of the experiment conducted based on the above experimental method, as shown in FIG. 5, in the conventional guide device that does not have the wear powder scattering prevention casing 1 and the wear powder scattering prevention cover 5, the amount of wear powder adhesion is 100 pieces. On the other hand, in the guide device of the present invention having only the abrasion powder scattering prevention housing 1 shown in FIG. Further, when the wear powder scattering prevention casing 1 and the wear powder scattering prevention cover 5 are provided, the number is reduced to ten. Further, by applying a voltage to the electrostatic adsorption sheets 4a and 4b, the amount of wear powder adhered was reduced to two. Therefore, the guide device of the present invention can greatly reduce wear powder scattering.

(Example 2)
Using the guide device of only the wear powder scattering prevention housing 1 used in Example 1, the distance between the facing surface of the wear powder scattering prevention housing 1 and the contact surface of the driving force transmission member 64 is 5, 10, Experiments were carried out at 50, 100, 200, 300, and 400 μm. The wear powder collecting groove 2 of the wear powder scattering prevention housing 1 has the groove width and depth of 2 mm. Each of the grooves is arranged such that two longitudinal directions thereof are perpendicular to the moving direction of the movable body, and the two grooves are parallel to each other.

Here, the moving profile of the stage 63 and the method for detecting the amount of wear powder were performed in the same manner as in Example 1. The result is shown in FIG.
As shown in FIG. 6, when the distance between the facing surface of the abrasion powder scattering prevention housing 1 and the contact surface of the driving force transmission member 64 is set between 10 and 300 μm, the amount of wear powder adhering is 30 or less. However, if it exceeds 300 μm, the amount of wear powder attached increases and the effect of the cover becomes low. On the other hand, when the thickness is less than 10 μm, the wear powder is caught in the contact surface between the facing surface of the wear powder scattering prevention housing 1 and the driving force transmission member 64, and the stage 63 does not operate.

(Example 3)
Furthermore, the wear powder collecting groove 2 of the wear powder scattering prevention housing 1 is used with the guide device of the wear powder scattering prevention housing 1 only used in Example 1, and the groove width and depth are 0.5, Experiments were performed with 1, 2, 3, 4, 5, 6, 7 mm. Each of the grooves is arranged such that two longitudinal directions thereof are perpendicular to the moving direction of the movable body, and the two grooves are parallel to each other. In addition, the distance between the facing surface of the abrasion powder scattering prevention casing 1 and the contact surface of the driving force transmission member 64 was set to 200 μm with little abrasion powder scattering in the above experiment.
Here, the moving profile of the stage 63 and the method for detecting the amount of wear powder were performed in the same manner as in Example 1. The result is shown in FIG.

  As shown in FIG. 7, when the groove width and depth are set to 1 to 5 mm, the amount of wear powder adhering to 30 pieces or less. The amount increases. If the opening width of this groove is narrower than the internal maximum width, there is an effect of collecting wear powder, but conversely if it is wider than the internal maximum width, the wear powder does not diffusely reflect and flows to the outside. The amount increases.

Example 4
Furthermore, the wear powder collecting groove 2 of the wear powder scattering prevention housing 1 is changed to 1, 2, 3 using the guide device of the wear powder scattering prevention housing 1 only used in the first embodiment. The experiment was conducted. In addition, the experiment was performed by changing the angle so that the number of grooves is two and the longitudinal direction of the grooves is 0, 60, 70, 80, 90, 100, 110, 120 degrees with respect to the moving direction of the movable body. went. The grooves are arranged so as to be parallel to each other, and the distance between the facing surface of the abrasion powder scattering prevention housing 1 and the contact surface of the driving force transmission member 64 is 200 μm with little abrasion powder scattering in the above experiment. did.
Here, the moving profile of the stage 63 and the method for detecting the amount of wear powder were performed in the same manner as in Example 1. The results are shown in Table 1.

Table 1

As shown in Table 1, when there are two or more wear powder collecting grooves 2a, 2b, the wear powder scattering rate is attenuated, so the amount of wear powder deposited becomes 30 or less, but the wear powder collecting grooves 2a, 2b However, if there is only one on one side, the scattering rate of the wear powder hardly attenuates, so that the wear powder jumps out of the wear powder collecting grooves 2a and 2b, and the amount of wear powder attached increases.
Furthermore, if the longitudinal direction of the groove is within the range of 90 ° ± 20 ° with respect to the moving direction of the movable body, the amount of wear powder attached is 30 or less, but conversely the range of 90 ° ± 20 °. If it exceeds the inside, irregular reflection of the wear powder is difficult to occur, and the amount of wear powder attached increases.

  The guide device according to the present invention relates to a guide device that drives a movable body that moves linearly or rotationally with an ultrasonic motor, and particularly in the atmosphere and vacuum used in precision processing machines, precision measurement devices, and semiconductor manufacturing devices. It is suitable as a guide device used therein.

It is a perspective view which shows the structure of the guide apparatus with respect to embodiment which concerns on this invention. It is a top view which shows the structure of the stage part and ultrasonic motor part in the guide apparatus of FIG. It is sectional drawing about the AA line of FIG. 2A. It is a top view which shows a mode when a stage is moved in FIG. 2A. It is sectional drawing about the BB line of FIG. 3A. It is a fragmentary sectional view which shows the more preferable form of the abrasion powder collection groove | channel in this Embodiment. It is a graph which shows the abrasion powder collection effect in the guide apparatus of Example 1 which concerns on this invention. It is a graph which shows the abrasion powder collection effect in the guide apparatus of Example 2 which concerns on this invention. It is a graph which shows the abrasion powder collection effect in the guidance apparatus of Example 3 which concerns on this invention. It is a perspective view which shows the structure of the guide apparatus which concerns on a prior art example. It is a top view which shows typically the structure of an ultrasonic motor.

Explanation of symbols

1: Housing for preventing abrasion powder scattering,
2a, 2b: Wear powder collecting groove,
3: Base,
4a, 4b: electrostatic adsorption sheet,
5: Abrasion powder scattering prevention cover,
56: friction member,
61: Base board,
62: a guide member,
63: Stage,
64: Driving force transmission member,
64a: contact surface,
65: Linear scale,
66: Measuring head,
67: Position detecting means,
68: Control unit,
69: Driver,
500: Ultrasonic motor.

Claims (8)

An ultrasonic motor having a vibrating body that moves elliptically and a friction member for transmitting the elliptical movement of the vibrating body;
A movable body that has a contact surface that contacts the friction member, and is movable by friction drive between the friction member and the contact surface;
In the guide device including opposing surfaces facing the contact surface on both sides of the ultrasonic motor, and a housing for preventing abrasion powder covering the ultrasonic motor,
A plurality of grooves are formed on each of the facing surfaces, and the distance between the contact surface and the facing surface and the shape of the grooves are set so that wear powder is captured in the grooves as the movable body moves. Guide device.   The guide device according to claim 1, wherein each of the grooves has a longitudinal direction substantially orthogonal to a moving direction of the movable body.   The guide device according to claim 1, wherein two or more grooves formed on each of the opposing surfaces are parallel to each other.   The guide device according to claim 1, further comprising a wear powder scattering prevention cover that covers the wear powder scattering prevention casing.   The guide device according to claim 4, wherein an adsorption sheet that adsorbs the wear powder is provided under the wear powder scattering prevention casing.   The distance between the contact surface and the facing surface is set in a range of 10 μm to 300 μm, and the groove width and depth are set in a range of 1 mm to 5 mm. Guide device.   The guide device according to claim 1, wherein an opening width of the groove is narrower than an internal maximum width. The guide device according to claim 7, wherein a width of a bottom surface of the groove is the maximum width.

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