JPH07205066A - Transport mechanism - Google Patents

Abstract

(57) [Abstract] [Object] Regarding a transfer mechanism for transferring a sample holder into a vacuum chamber of an electron beam exposure apparatus, a drive source dedicated to a clamp mechanism is not required, and there are no restrictions on mounting conditions, and the mechanism is simple. It is an object of the present invention to provide a transport mechanism that is inexpensive and enables the clamp mechanism to reliably operate. [Structure] The clamp mechanism 12 that clamps / releases an object to be transferred 30 by using the motion of the articulated transfer arm 11 near the dead point is provided on a guide plate 27 of the articulated transfer arm 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer mechanism for transferring a sample holder into a vacuum chamber such as an electron beam exposure apparatus.

[0002]

2. Description of the Related Art A transport mechanism for feeding a sample holder into a vacuum chamber such as an electron beam exposure apparatus requires that the sample holder be clamped and pushed into the vacuum chamber, and the exposed sample holder be re-clamped and pulled back. . Therefore, a loader mechanism and a clamp mechanism are required. There are the following two types of such transport mechanisms.

FIG. 9 is a block diagram of a conventional transport mechanism. In the figure, reference numeral 1 is an articulated transfer arm using two sets of cardan circles as a loader mechanism. The articulated transfer arm 1 is provided with a clamp mechanism 3 that holds / releases the sample holder 2. The clamp mechanism 3 is driven by a solenoid 4 and an air cylinder provided on the articulated transfer arm 1.

In addition, there is also one in which a drive source for the clamp mechanism is not provided on the articulated transfer arm 1 but a drive source is provided on the base side and power is supplied to the clamp mechanism using a transmission shaft that expands and contracts.

Only the clamp mechanism is stopped by an external stopper during the stroke of the loader mechanism, and the clamp mechanism is opened and closed by the driving force of the stroke of the remaining loader.

[0006]

However, the transport mechanism having the above structure has the following problems. Since the drive source of the clamp mechanism is provided on the loader mechanism, the loader mechanism becomes heavy. Moreover, the electric wire of the drive source is required, and the electric wire is dragged during the driving of the loader mechanism. Further, due to noise or the like, an inadvertent malfunction occurs.

There are restrictions on the mounting conditions for the clamp mechanism, the stopper provided outside, and the like. The present invention has been made in view of the above problems, and an object of the present invention is that a drive source dedicated to a clamp mechanism is unnecessary, the mounting conditions are not limited, the mechanism is simple, the cost is low, and the clamp mechanism is reliable. It is to provide a transport mechanism capable of various operations.

[0008]

According to a first aspect of the present invention for solving the above-mentioned problems, a fixed base, a drive source for driving a gear fixed to the base, and a rotatably provided on the base, A first joint arm driven by a drive source, a first gear arranged at the center of rotation of the first joint arm and fixed to a base, rotatably at a rotation end of the first joint arm A second joint arm provided with a second gear that is provided at the center of rotation thereof and that engages with the first gear and has a gear ratio with the first gear of 2: 1; A third gear disposed at the center of rotation and fixed to the first joint arm, rotatably provided at the rotating end of the second joint arm, and meshing with the third gear,
The guide plate includes a fourth gear having a gear ratio of 1: 2 with the third gear, and each of the first gear, the second gear, the second gear, and the fourth gear. The articulated transfer arm in which the distances between the rotation centers of the two are set equal to each other and the guide plate of the articulated transfer arm are provided, and the transferred object is pinched / released by using the motion near the dead point of the articulated transfer arm. And a clamp mechanism that operates.

According to a second aspect of the present invention, in the clamp mechanism according to the first aspect of the present invention, the base end portion is rotatably attached to the guide plate, and the first and the second portions hold and release the object to be conveyed in cooperation.
And a second hook, a first urging member that urges the first and second hooks in the anti-clamping direction, a lever having an intermediate portion rotatably provided on the guide plate, and the first hook. A first pin provided on a side portion of the second joint arm and capable of abutting on one rotating end of the lever; and the first pin on the guide plate.
And a linear guide provided between the second hook, a slider slidably engaged on the linear guide, and a first rotary end of the lever, the base end of which is rotatably provided.
Link and an intermediate part are rotatably provided on the first hook, one end is rotatably attached to a tip part of the first link, and the other end is rotatably attached to the slider. A second link attached thereto, and a third link having one end rotatably attached to the second hook and the other end rotatably attached to the slider. is there.

According to a third aspect of the invention, instead of the third link of the second aspect of the invention, an intermediate portion is rotatably provided on the second hook, and one end of the slider is rotatable on the slider. A third pin attached to the second pin which is erected on the other rotating end of the lever, and a base end which is rotatable on the other rotating end of the third 'link. The second pin is attached to the rotating end side, and the second pin abuts on the first pin and the second pin to hold the first and second hooks in a sandwiched state. The first hook and the second hook hold the release groove in the released state, the third hook formed with the guide portion for guiding the second pin from the release groove to the holding portion, and the third hook. Alternate mechanism including a second biasing member that rotationally biases in the second pin direction It is those provided.

[0011]

In the transport mechanism according to the first and second aspects of the invention, the clamp mechanism clamps / releases the object to be transported by the movement of the articulated transport arm in the vicinity of the dead point.

In the transport mechanism of the invention according to claim 3,
The third hook and the second pin realize an alternate mechanism that holds the clamped / released state of the clamp mechanism with respect to the transported object.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to the drawings. 1 is a plan view of an embodiment of the present invention, FIG. 2 is a front sectional view of FIG. 1, FIG. 3 is a view for explaining the operation of the articulated transfer arm shown in FIG. 2, and FIG. 4 is an articulated type shown in FIG. FIG. 5 is a diagram illustrating all steps of the operation of the transfer arm, and FIG.
6 is an enlarged view of the hook of FIG. 6, FIG. 6 is a front view of FIG. 5, FIG. 7 and FIG.
FIG. 3 is a diagram for explaining the operation of the clamp mechanism in FIG. 1.

The transfer mechanism of this embodiment comprises an articulated transfer arm 11 and a clamp mechanism 12 provided on the articulated transfer arm 11. First, the articulated transfer arm 11 will be described with reference to FIG.

A motor 15 as a drive source for driving the pinion 14 is fixed to the base 13. Further, a shaft 16 is erected on the base 13, and a first joint arm 17 is rotatably attached to the shaft 16.

A gear portion 17a meshing with the pinion 14 of the motor 15 is formed in the lower portion of the first joint arm 17, a shaft 18 is erected at the rotating end portion, and a shaft 19 is rotated at the intermediate portion. It is possible.

The shaft 16 is provided with a first gear 20, and the shaft 19 is provided with an intermediate gear 21 which meshes with the first gear 20.
Are installed respectively. A gear portion 22 a as a second gear that meshes with the intermediate gear 21 is provided below the second joint arm 22 rotatably attached to the shaft 18.
Are formed. Here, the first gear 20 and the gear portion 2
The gear ratio with 2a is set to 2: 1.

A shaft 23 is rotatably attached to the rotating end portion of the second joint arm 22, and a shaft 24 is rotatably attached to the middle portion thereof. The shaft 18 has a third gear 2
5, the shaft 24 is provided with an intermediate gear 26 that meshes with the third gear 25. A guide plate 27 provided with the clamp mechanism 12 is attached to the shaft 23,
A gear portion 27 a as a fourth gear that meshes with the intermediate gear 26 is formed on the lower portion of the guide plate 27. Here, the gear ratio between the third gear 25 and the gear portion 27a is 1:
It is set to 2. Further, the distance (l) between the rotation centers of the first gear 20 and the gear portion 22a as the second gear, and the distance between the rotation centers of the gear portion 22a as the second gear and the fourth gear 27a. The distance (l ') is set equal.

Next, the operation of the articulated transfer arm having such a structure will be described with reference to FIG. Now, as shown in FIG. 3A, the initial state is a state in which the first joint arm 17, the second joint arm 22, and the guide plate 27 are aligned. When the motor 15 is rotated, its rotational force is the pinion 1
4 is transmitted to the gear portion 17a. When the gear portion 17a rotates, the first joint arm 17 integrated with the gear portion 17a also rotates. Here, as shown in FIG. 6 (b), the first joint arm 17 moves counterclockwise until the rotation angle (θ) = α with respect to the line L1.
It shall be rotated in the (CCW) direction. At this time, the rotation direction of each gear is as shown by the arrow in (b).

In this state, the gear ratio of the first gear 20 and the gear portion 22a, which is the second gear, is 2: 1. Therefore, the second joint arm 22 integrated with the gear portion 22a forms a straight line L2. On the other hand, it is displaced by 2α, which is twice α. Therefore, the triangle ABC consisting of the center points A, B, and C of the first gear 20, the gear portion 22a, and the gear portion 27a that is the fourth gear is always an isosceles triangle with ∠A = ∠C. In this case, it is mechanically known that the other one point C always moves on the side AC (Cardan mechanism). Applying this principle, if there is a gear ratio of 1: 2 between the third gear 25 and the gear portion 27a that is the fourth gear, if the guide plate 27 is considered to be fixed, the point C On the other hand, point A moves linearly. In fact, since the base 13 is fixed, the guide plate 27 stands on the straight line AC regardless of whether the first joint arm 17 rotates in the clockwise direction (CW direction) or the counterclockwise direction (CCW direction). Translate without changing.

FIG. 4 is a view showing all the steps of moving the articulated transfer arm 11 shown in FIG. The entire process is completed by rotating the first joint arm 17 counterclockwise by about 180 °. When returning to the original position, the first joint arm 17 may be rotated clockwise this time.

Next, the clamp mechanism 12 will be described with reference to FIG. On the guide plate 27, the base end is the guide plate 27.
Is rotatably attached to and holds the transported object 30 in cooperation.
A first hook 31 and a second hook 32 for releasing are provided. These first and second hooks 31, 32
Are urged in the anti-clamping direction by a spring 33 as a first urging member engaged with both.

On the center of rotation of the guide plate 27, the lever 3
The middle part of 4 is rotatably mounted. In addition, a long hole 27b as a linear guide is provided at the rotating end of the guide plate 27.
Are formed.

A first pin 35 is provided on the side portion of the second joint arm 22 so as to come into contact with one rotating end of the lever 34. The other rotating end of the lever 34 has a first
The base end portion of the first link 36 extending toward the hook 31 is rotatably attached. An intermediate portion of the second link 37 is rotatably attached near the rotation base end portion of the first hook 31, and one rotation end portion of the second link 37 is a tip end portion of the first link 36. Is rotatably mounted on. Further, the other rotating end of the second link 37 is
It is rotatably attached to a pin 38 as a slider that slidably engages with the elongated hole 27b.

In the vicinity of the rotation base end portion of the second hook 32,
The middle part of the third link 39 is rotatably mounted. One rotating end of the third link 39 is rotatably attached to the pin 38 described above.

These second link 37 and third link 3
By the mechanism composed of 9, the pin 38 and the elongated hole 27b, the pin 38 moves along the elongated hole 27b, so that the first hook 31 and the second hook 32 perform opening / closing operation (holding / releasing operation).

At the other rotating end of the third link 39,
The rotation base end of the third hook 40 that realizes the alternate mechanism is rotatably attached using a pin 41.
Since the configuration of the third hook 40 is complicated, FIG.
Will be described with reference to FIG. A second pin 42 is erected on the other rotating end of the lever 34. On the rotation end side of the third hook 40, a holding portion 40a with which the second pin 42 can abut, and a side portion of the third hook 40 are obliquely cut inward toward the tip direction, The release groove 40b with which the second pin engages, and the second pin 42 that is bent upward in the release groove 40b and extends from the release groove 40b to the holding portion 40a.
A guide portion 40c for guiding the release groove 40 and a holding portion 40a.
An evacuation part 40d adjacent to the other via b is formed.

The intermediate portion of the third hook 40 is a pin 4
It is wound around 1, and one end is locked to the third link 39,
The other end is urged in the direction of the second pin 42 by a spring 43 serving as a second urging member locked to the third hook.

Next, the operation of the clamp mechanism having the above structure will be described with reference to FIGS. 7 and 8. In FIG. 7A, when the rotation angle θ of the first joint arm 17 is 0 °, the first hook 31 and the second hook 32 of the clamp mechanism 12 are closed, and the transported object 30 is held. At this time, the holding portion 40a of the third hook 40 presses the second pin 42.

Next, as shown in (b), when the first joint arm 17 is rotated clockwise, the guide plate 27 moves in parallel without changing its posture, and at θ = 180 ° (top dead center). The transport target position of the transported object 30 is reached. Second from around θ = 180 °
The first pin 35 of the articulated arm 22 pushes the lever 34, and the lever 34 starts to rotate counterclockwise.

Then, as shown in (c), when the first joint arm 17 is further rotated clockwise by θ = 185 °, the second pin 42 on the lever 34 rotated counterclockwise is
The third hook 40 moves from the holding portion 40a of the third hook 40 through the release groove 40b to the retracting portion 40d of the third hook 40.
Along with the movement of the second pin 42, the lever 34 rotates counterclockwise, and the first hook 36 and the second hook 37 and the second link 37 pass through the first link 36, the second link 37, and the third link 39. The hook 32 is opened against the urging force of the spring 33, and the conveyed object 30 is released from the pinched state.

Next, as shown in FIG. 8 (d), when the first joint arm 17 is returned counterclockwise to θ = 180 °, the first pin 35 of the second joint arm 22 is rotated clockwise. The lever 34 also rotates clockwise, and the second pin 42 on the lever 34 moves from the retracting portion 40d of the third hook 40 to the release groove 4a.
0b and engages the release groove 40b. Also at this time,
Through the first link 36, the second link 37, and the third link 39, the first hook 31 and the second hook 32
Is open against the biasing force of the spring 33.

That is, the movement of the articulated transfer arm 11 near the dead point (θ = 175 ° → θ = 180 ° → θ = 185 ° → θ = 180 °) is used to release the clamp mechanism 12 from the clamped state. Has been made.

At this time, the speed of the guide plate 27, which changes according to the sine curve, becomes extremely low near the dead center (θ = 0 °, 180 °), and the stroke (movement amount of the guide plate 27) changes. Is few. Further, in such a transport mechanism, a mechanism is provided in which the fixed position of the transported object 30 is not determined only by the stop position of the guide plate 27 and the transported object 30 is called up to a fixed position on the other side. Therefore, the stop position of the guide plate 27 does not matter in practice even if it is not strict.

Then, as shown in (e), the first joint arm 17 is rotated counterclockwise and returned to θ = 0 °. Here, the difference between FIG. 7 (a) and FIG. 8 (e) is that the second pin 42 on the lever 34 engages with the release groove 40 b of the third hook 40, and the first and second This is the point where the hooks 31 and 32 are open.

Next, in order to recover the transported object 30, the first joint arm 17 is rotated clockwise by 180 °,
The guide plate 27 (clamp mechanism 12) is moved in parallel to the target position. Then, when the first joint arm 17 is rotated up to about θ = 185 °, the second pin 42 on the lever 34 slips under the guide portion 40c of the third hook 40 and moves to the holding portion 40a, The first and second hooks 31, 32 hold the transported object 30.

That is, the movement of the articulated transfer arm 11 near the dead point (θ = 175 ° → θ = 180 ° → θ = 185 ° → θ = 180 °) is used to clamp the clamp mechanism 12 from the released state to the clamped state. Will be made.

In this state, when the angle is returned to θ = 0 °, FIG. 7 (a)
In this state, the article 30 is completely recovered. According to the above configuration, the top dead center (θ = 18
Since the clamp mechanism 12 is clamped / released by using the movement in the vicinity of (0 °), a dedicated drive source such as the conventional clamp mechanism is unnecessary.

Also, there are no restrictions on the mounting conditions, the mechanism is simple and inexpensive, and the clamp mechanism can operate reliably.
The present invention is not limited to the above embodiment. In the above embodiment, the third hook 40 and the second pin 42 are provided in order to realize the alternate operation of the clamp mechanism 12. However, the third hook 40 and the second pin 42 can be eliminated by providing a mechanism for moving the set transferred object 30 up and down on the side receiving the transferred object 30. This clamp mechanism 12 is θ = 180 °
The release operation is performed in the vicinity, and the clamping state is always established at other rotation angles. In this case, the third link 39 is
It is only necessary to connect with the hook 32 of.

Further, in the above embodiment, the first joint arm 17 is rotated up to θ = 185 ° so that the stroke of the lever 34 can be sufficiently taken. However, the lever 34, the first link 36, and the second link 36 If the link ratio of the link mechanism composed of the link 37 and the third link 39 is set appropriately and the opening angle of the first and second hooks 31 and 32 can be sufficiently secured, even if the rotation is up to θ = 180 °. It is possible.

Further, in the above embodiment, the elongated hole 27b is provided as the linear guide provided on the guide plate 27 and the pin 38 is provided as the slider, but the present invention is not limited to this. For example, the linear guide may be a rail laid on the guide plate 27, and the slider may be a roller slidably engaged with the rail.

[0042]

As described above, according to the present invention, the object to be conveyed is clamped by using the motion of the articulated transfer arm near the dead point.
By providing the clamp mechanism for releasing / releasing on the guide plate of the articulated transfer arm, there is no need for a dedicated drive source for the clamp mechanism, there are no restrictions on the mounting conditions, and the mechanism is simple, inexpensive, and reliable. A transport mechanism capable of various operations can be realized.

The clamp mechanism has a third hook and a second hook.
Since the pin is provided, it is possible to realize an alternate mechanism that holds the clamped / released state of the clamp mechanism with respect to the transported object.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of the present invention.

FIG. 2 is a front sectional view of FIG.

FIG. 3 is a diagram for explaining the operation of the articulated transfer arm shown in FIG.

FIG. 4 is a diagram illustrating all steps of the operation of the articulated transfer arm shown in FIG.

5 is an enlarged view of a third hook in FIG. 1. FIG.

FIG. 6 is a front view of FIG.

FIG. 7 is a diagram illustrating the operation of the clamp mechanism in FIG.

FIG. 8 is a diagram for explaining the operation of the clamp mechanism in FIG.

FIG. 9 is a configuration diagram of a conventional transport mechanism.

[Explanation of symbols]

 13 base 11 articulated transfer arm 12 clamp mechanism 15 motor (driving source) 17 first joint arm 20 first gear 22 second joint arm 22a second gear 25 third gear 27 guide plate 27a fourth gear

Claims (3)

[Claims] 1. A fixed base (13), a drive source (15) for driving a gear fixed to the base (13), and a rotatably provided on the base (13), the drive source (15). A first articulated arm (1
7), a first gear (2) arranged at the center of rotation of the first joint arm (17) and fixed to a base (13)
0), rotatably provided at the rotation end of the first joint arm (17), and the first gear (2
0), and the gear ratio with the first gear (20) is 2:
A second joint arm (22) having one second gear (22a), disposed at the center of rotation of the second joint arm (22), and fixed to the first joint arm (17) A third gear (25), the second joint arm (22)
Rotatably provided at the rotation end of the third gear (2
5), and the gear ratio with the third gear (25) is 1:
A guide plate (27) having two fourth gears (27a), the first gear (20) and the second gear (2).
2a), an articulated transfer arm (11) in which the distances between the respective rotation centers of the second gear (22a) and the fourth gear (27a) are set equal, and the articulated transfer arm (11) And a clamp mechanism (12) which is provided on the guide plate (27) and clamps / releases the transferred object (30) by using the movement of the articulated transfer arm (11) near the dead point. Characteristic transport mechanism. 2. The clamp mechanism includes first and second hooks, the base end of which is rotatably attached to the guide plate, and which cooperates to hold / release a transported object, and the first and second hooks. First urging member for urging the hook in the anti-clamping direction, a lever having an intermediate portion rotatably provided on the guide plate, and a lever provided on a side portion of the second joint arm. A first pin capable of abutting on one of the rotating ends, a linear guide provided on the guide plate between the first and second hooks, and slidably engaged on the linear guide. A slider; a first link having a base end rotatably provided on the other rotation end of the lever; an intermediate part rotatably provided on the first hook; and one end of the first link One of the links is rotatably attached to the tip, and the other end is rotatably attached to the slider. A second link operably attached to the slider, one end rotatably attached to the second hook, and the other end rotatably attached to the slider. The transport mechanism according to claim 1, wherein: 3. A third 'link in which an intermediate portion is rotatably provided on the second hook and one end of which is rotatably attached to the slider is used instead of the third link, A second pin erected on the other rotation end of the lever and a base end rotatably attached to the other rotation end of the third 'link are rotatably mounted on the rotation end side. A pin that holds the first and second hooks in a pinched state by abutting two pins, and a pin that holds the second pin hold the first and second hooks in a released state A release groove, a third hook having a guide portion for guiding the second pin from the release groove to the holding portion, and a second hook for rotationally biasing the third hook in the second pin direction. 3. An alternate mechanism comprising a biasing member of the above is provided. Transport mechanism.