JP2024098897A - Drive unit - Google Patents

Abstract

[Problem] A movable body can be moved stably. [Solution] A driving device according to the present disclosure has a driving section, a movable section, and a connecting section. The driving section has a first guide rail extending along a first direction, and a driving body movable along the first guide rail. The movable section has a second guide rail extending along the first direction, and a movable body movable along the second guide rail. The connecting section connects the driving body and the movable body. When the moving distance of the driving body in the first direction is defined as a first distance, the moving distance of the movable body in the first direction is the first distance. When a direction perpendicular to the first direction is defined as a second direction, the connecting section transmits a driving force in the first direction generated by the driving body to the movable body while allowing the driving body to move in the second direction. [Selected Figure] Figure 1

Description

This disclosure relates to a drive device.

Conventionally, there is known a driving device that moves a movable body along a guide member. For example, Patent Document 1 discloses a linear driving device for focusing that uses a piezoelectric actuator as a linear driving source.

Japanese Patent Application Publication No. 9-158948

This disclosure provides technology that allows a movable body to move stably.

A driving device according to one aspect of the present disclosure has a driving unit, a movable unit, and a connecting unit. The driving unit has a first guide rail extending along a first direction and a driving body movable along the first guide rail. The movable unit has a second guide rail extending along the first direction and a movable body movable along the second guide rail. The connecting unit connects the driving body and the movable body. When the moving distance of the driving body in the first direction is defined as a first distance, the moving distance of the movable body in the first direction is the first distance. When the direction perpendicular to the first direction is defined as a second direction, the connecting unit transmits the driving force in the first direction generated by the driving body to the movable body while allowing the driving body to move in the second direction.

According to the present disclosure, it is possible to move the movable body stably.

FIG. 1 is a schematic plan view illustrating an example of the configuration of a drive device according to an embodiment. FIG. 2 is a schematic plan view showing a configuration example of a connection portion according to the embodiment. FIG. 3 is a schematic cross-sectional view taken along the line III-III in FIG. FIG. 4 is a diagram illustrating an example of the operation of the drive device according to the embodiment. FIG. 5 is a diagram illustrating an example of the operation of the drive device according to the embodiment. FIG. 6 is a schematic plan view showing a configuration example of a drive device according to a modified example of the embodiment.

Below, a detailed description will be given of a form for implementing a drive device according to the present disclosure (hereinafter, referred to as an "embodiment") with reference to the drawings. Note that the present disclosure is not limited to this embodiment. Furthermore, each embodiment can be appropriately combined as long as the processing content is not contradictory. Furthermore, the same parts in each of the following embodiments are given the same reference numerals, and duplicated descriptions will be omitted.

In addition, in the embodiments described below, expressions such as "constant," "orthogonal," "vertical," and "parallel" may be used, but these expressions do not necessarily mean "constant," "orthogonal," "vertical," or "parallel" in the strict sense. In other words, each of the above expressions allows for deviations due to, for example, manufacturing precision, installation precision, and the like.

In addition, in order to make the explanation easier to understand, the drawings referred to below may show an orthogonal coordinate system in which the X-axis, Y-axis, and Z-axis directions are defined as being perpendicular to each other, and the positive direction of the Z-axis is the vertically upward direction. Also, the direction of rotation about the vertical axis may be referred to as the θ direction.

Conventionally, there is known a driving device that moves a movable body in a moving direction along a guide member. For example, Patent Document 1 discloses a linear driving device for focusing that uses a piezoelectric actuator as a linear driving source.

However, in the technology described in Patent Document 1, the table, which is the movable body, and the piezoelectric actuator, which is the driving body, are fixed together. Therefore, if deformation or malfunction occurs in any of the movable body, driving body, or guide member, there is a risk that the linear movement of the movable body will be hindered. Even if there is no deformation or malfunction, external factors such as vibrations may hinder the linear movement of the movable body. For this reason, there is room for further improvement in terms of stably moving the movable body.

Therefore, there is a need for technology that can move movable objects stably.

(Embodiment)
First, a configuration example of a driving device 100 according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing a configuration example of a driving device 100 according to an embodiment.

The drive device 100 may have a drive unit 1, a movable unit 2, and a connecting unit 3.

The drive unit 1 may have a first guide rail 11 and a drive body 12. The first guide rail 11 may extend along the movement direction of the drive body 12, here the X-axis direction.

The driver 12 may be provided on the first guide rail 11. The driver 1 may have a driver 121 such as a motor. The driver 12 can move along the extension direction of the first guide rail 11, here the X-axis direction, by the power generated by the driver 121. The driver 12 may move back and forth along the first guide rail 11. That is, the driver 12 may be capable of moving in both the positive X-axis direction and the negative X-axis direction.

The driver 12 may have, for example, a ball bearing. In this case, the driver 12 may contact the first guide rail 11 via the ball bearing.

In the illustrated example, the driving source 121 is located inside the driving body 12, but the driving source 121 does not necessarily have to be located inside the driving body 12. For example, the driving source 121 may be a ball screw and a motor provided outside the driving body 12.

The movable unit 2 may have a second guide rail 21 and a movable body 22. The second guide rail 21 may extend along the movement direction of the movable body 22, here the X-axis direction. The first guide rail 11 and the second guide rail 21 of the drive unit 1 may be arranged parallel to each other with a gap in a direction perpendicular to the movement direction, here the Y-axis direction.

The movable body 22 may be provided on the second guide rail 21. The movable body 22 may be movable along a moving direction, here the X-axis direction. The movable body 22 may have a gas supply source 221. The movable body 22 can float relative to the second guide rail 21 by blowing compressed gas supplied from the gas supply source 221 toward the second guide rail 21. In this case, the movable body 22 can move without contacting the second guide rail 21. A movable part 2 of this type is sometimes called an air slide.

The connection unit 3 may connect the driving body 12 and the movable body 22. The power generated by the movement of the driving body 12 is transmitted to the movable body 22 by the connection unit 3. This allows the driving device 100 to move the movable body 22 along the second guide rail 21.

The movable body 22 may have a higher straightness than the driving body 12. Straightness refers to the degree of deviation from a straight line in the movement trajectory of the driving body 12 or the movable body 22. In this specification, "high straightness" means that the movement trajectory deviates less from a straight line, i.e., moves more linearly. On the other hand, "low straightness" means that the movement trajectory deviates more from a straight line. For example, a movable body 22 using a non-contact bearing such as an air slide as in the embodiment may have a higher straightness than a driving body 12 using a contact bearing such as a ball bearing.

If the straightness of the driver 12 is lower than that of the movable body 22, the driver 12 will move relatively closer to or farther away from the movable body 22 while moving along the first guide rail 11 due to its low straightness. Therefore, if the driver 12 and the movable body 22 were fixed together, movement of the driver 12 in a direction other than the X-axis direction would be transmitted directly to the movable body 22, which could cause the straightness of the movable body 22 to decrease.

In addition, even if the straightness of the driver 12 is the same as that of the movable body 22, for example, if the first guide rail 11 is deformed, the driver 12 may have difficulty moving with the same straightness as the movable body 22. Even in such a case, if the driver 12 and the movable body 22 are fixed integrally, the movement of the driver 12 may reduce the straightness of the movable body 22. In addition, if the driver 12 and the movable body 22 are fixed integrally, for example, vibrations of the driver 12 are easily transmitted to the movable body 22, and such vibrations may reduce the straightness of the movable body 22.

The connection part 3 of the driving device 100 is designed to transmit only the component of the driving force generated by the driving body 12 in the X-axis direction to the movable body 22. The configuration of the connection part 3 will be described in detail below.

The connection portion 3 may have a first member 31 and multiple, here two, second members 32. The first member 31 may be located on one side of the movable body 22 and the driving body 12, and the second member 32 may be located on the other side of the movable body 22 and the driving body 12. In the example shown in FIG. 1, the first member 31 is located on the driving body 12, and the second member 32 is located on the movable body 22.

As shown in FIG. 1, the first member 31 may be spherical. The first member 31 may be disposed between two second members 32. The first member 31 may be fixed to the driver 12 via a rod-shaped body 33 located in the driver 12. The connection portion 3 does not necessarily have to have a rod-shaped body 33. That is, the first member 31 may be fixed directly to the driver 12. The rod-shaped body 33 does not necessarily have to be rod-shaped, and may have any shape as long as it has the function of connecting the first member 31 and the driver 12.

The second member 32 may be a flat member. The second member 32 can be brought into contact with and separated from the first member 31. In other words, the second member 32 is not fixed to the first member 31.

Such a connection part 3 can transmit the driving force in the X-axis direction generated by the driver 12 to the movable body 22 while allowing the driver 12 to move in directions perpendicular to the X-axis direction, in this case, in the Y-axis direction and the Z-axis direction. An example of such an operation will be described later with reference to Figures 4 and 5.

Here, a detailed configuration example of the connection unit 3 according to the embodiment will be described with reference to Figs. 2 and 3. Fig. 2 is a schematic plan view showing a configuration example of the connection unit 3 according to the embodiment. Fig. 3 is a schematic cross-sectional view taken along the line III-III shown in Fig. 2. Fig. 3 is a side view of the connection unit 3 as viewed from the drive unit 1 side.

As shown in FIG. 3, the driver 12 may have a first main surface 122 and a second main surface 123. The first main surface 122 may be the upper surface of the driver 12. The second main surface 123 may be the lower surface of the driver 12. In this case, the first member 31 may be located on the first main surface 122 side of the driver 12. Specifically, the first member 31 may be located on the first main surface 122 side of the driver 12 relative to the center of the driver 12.

2, the two second members 32 may be arranged at an interval in the X-axis direction, which is the movement direction of the movable body 22. The two second members 32 may be arranged to sandwich the first member 31 from both sides in the X-axis direction. Specifically, as shown in FIGS. 2 and 3, one of the two second members 32 may be arranged on the negative X-axis side relative to the first member 31, and the other may be arranged on the positive X-axis side relative to the first member 31.

As shown in FIG. 3, the distance D1 between the two second members 32 may be greater than the diameter D2 of the first member 31. In other words, when the first member 31 is disposed between the two second members 32, a gap may be formed between the first member 31 and the second member 32.

Next, an operation example of the driving device 100 according to the embodiment will be described with reference to Figs. 4 and 5. Figs. 4 and 5 are diagrams showing an operation example of the driving device 100 according to the embodiment. Fig. 4 shows an operation example when the movable part 2 is moved in the positive direction of the X-axis. Fig. 5 shows an operation example when the movable part 2 is moved in the negative direction of the X-axis.

As shown in FIG. 4, the first member 31 of the connection portion 3 is in contact with the second member 32. Specifically, the end of the first member 31, which is a spherical body, on the X-axis positive side may be in point contact with the second member 32, which is a plate-like body arranged on the X-axis positive side. In this state, when the driver 12 moves in the X-axis positive direction along the first guide rail 11, the driving force of the driver 12 is transmitted to the movable body 22 via the first member 31 and the second member 32. As a result, the movable body 22 moves in the X-axis positive direction following the driver 12.

As shown in FIG. 5, when the driver 12 is moved in the negative X-axis direction along the first guide rail 11, the first member 31 of the connection part 3 comes into contact with the other second member 32. Specifically, the end of the first member 31 on the negative X-axis direction side comes into point contact with the second member 32 arranged on the negative X-axis direction side. In this state, when the driver 12 moves in the negative X-axis direction along the first guide rail 11, the driving force of the driver 12 is transmitted to the movable body 22 via the first member 31 and the second member 32. As a result, the movable body 22 moves in the negative X-axis direction following the driver 12.

When the movement distance of the driver 12 in the X-axis direction is defined as a first distance, the movement distance of the movable body 22 in the X-axis direction is the same first distance as the driver 12. In other words, the movable body 22 moves the same distance as the driver 12 moves.

As described above, the first member 31 and the second member 32 can be moved toward and away from each other. Therefore, the connection unit 3 can allow the driver 12 to move toward or away from the movable body 22 relative to the movable body 22 while the driver 12 and the movable body 22 are moving, that is, the driver 12 to move in the Y-axis direction or Z-axis direction perpendicular to the X-axis direction. In other words, the connection unit 3 can release the driving force in the Y-axis direction or Z-axis direction that is generated when the driver 12 moves in the Y-axis direction or Z-axis direction relative to the movable body 22. This allows the connection unit 3 to transmit only the X-axis component of the driving force generated by the driver 12 to the movable body 22. Therefore, the movable body 22 can be moved stably in the moving direction.

In addition, the first member 31 and the second member 32 of the connection part 3 are in point contact, so the contact area can be reduced. This makes it more difficult for components of the driving force generated by the driver 12 in the direction other than the X-axis to be transmitted to the movable body 22.

In addition, with the driving device 100 according to the embodiment, by using the above-mentioned connecting portion 3, it is not necessary to use a driving body with high rigidity, high accuracy, and long life, and the cost of the device itself can be reduced. In addition, for example, the movement of the movable body 22 can be automated, and costs can be reduced, compared to when the driving body 12 is moved manually.

When the driver 12 moves in the positive direction of the X-axis, it comes into point contact with the second member 32 located on the positive side of the X-axis, and when the driver 12 moves in the negative direction of the X-axis, it comes into point contact with the second member 32 located on the negative side of the X-axis. Therefore, the movable body 22 can be moved stably not only in one direction, but also in the opposite direction.

(Modification)
Fig. 6 is a diagram showing a configuration example of a driving device 100 according to a modified example of the embodiment. As shown in Fig. 6, the movable body 22 of the driving device 100 may have a sensor 222. The sensor 222 may be a sensor that measures the flatness, shape, thickness, etc. of a measurement object such as a substrate S.

This configuration makes it possible to measure the flatness, shape, thickness, etc. of the object to be measured while reducing the effect of poor installation accuracy and running precision of the driver 12 on the movable body 22.

In one embodiment, (1) a drive device (for example, drive device 100) has a drive unit (for example, drive unit 1), a movable unit (for example, movable unit 2), and a connection unit (for example, connection unit 3). The drive unit has a first guide rail (for example, first guide rail 11) extending along a first direction, and a drive body (for example, drive body 12) that can move along the first guide rail. The movable unit has a second guide rail (for example, second guide rail 21) extending along the first direction, and a movable body (for example, movable body 22) that can move along the second guide rail. The connection unit connects the drive body and the movable body. When the movement distance of the drive body in the first direction is the first distance, the movement distance of the movable body in the first direction is the first distance. When the direction perpendicular to the first direction is defined as the second direction, the connection portion transmits the driving force generated by the driver in the first direction to the movable body while allowing the driver to move in the second direction.

(2) In the drive device of (1) above, the connection part has a first member located on one side of the movable body and the drive body, and a second member located on the other side of the movable body and the drive body and capable of moving toward and away from the first member, and the first member is spherical. The drive device of claim 1.

(3) In the drive device of (2) above, the first member and the second member may be in point contact.

(4) In any one of the drive devices (1) to (3) above, the movable body may have a sensor.

The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims.

REFERENCE SIGNS LIST 1 Drive section 2 Movable section 3 Connection section 11 First guide rail 12 Drive body 21 Second guide rail 22 Movable body 31 First member 32 Second member 100 Drive device 222 Sensor

Claims (4)

A first guide rail extending along a first direction;
a drive unit having a drive body movable along the first guide rail;
A second guide rail extending along the first direction;
a movable portion having a movable body movable along the second guide rail;
a connection portion that connects the driving body and the movable body,
When a moving distance of the driving body in the first direction is a first distance, a moving distance of the movable body in the first direction is the first distance,
A drive device in which, when a direction perpendicular to the first direction is a second direction, the connection portion transmits the driving force in the first direction generated by the drive body to the movable body while allowing the drive body to move in the second direction. The connection portion is
A first member located on one of the movable body and the driving body;
a second member located on the other side of the movable body and the driving body and capable of coming into contact with and being separated from the first member;
The drive mechanism of claim 1 , wherein the first member is spherical. The drive device according to claim 2, wherein the first member and the second member are in point contact. The drive device according to any one of claims 1 to 3, wherein the movable body has a sensor.

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