JP3222230B2 - Small movement XYθ table - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear motion for a small distance along the X-axis direction and the Y-axis direction in XY coordinates, and X,
The present invention relates to an XYθ table that performs a rotational motion at a small angle θ with respect to both Y axes, and particularly to a table having high rigidity.

[0002]

2. Description of the Related Art When constructing an XYθ table, X, Y
In general, a feed mechanism using screws and gears and a speed reduction mechanism such as a worm and a worm wheel are coupled to a feed system and a rotation system in which each shaft is independent, and each table is driven independently.

[0003]

In this construction, a high rigidity XYθ table is manufactured by the rigidity of the linear motion guide and the rotating shaft, the rigidity of the screws, the rigidity of the engagement between the worm and the worm wheel, and the rigidity of each bearing. It is difficult.

The present invention has been made in consideration of the above points, and has as its object to provide an XYθ table having high rigidity.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has four pairs of cam sets each having a pair of rotating cams of the same shape and arranged at each corner of a square. Are arranged so that the distance between adjacent ones of these cam sets is equal, and the distance between opposing ones is also equal. When these cams are rotated by an equal angle in a predetermined direction, the mutual distance is set. A set of cams arranged so as to maintain a predetermined value, each having a pair of rolling linear guides in contact with the peripheral surface of the cam, a guide bar arranged between these rolling linear guides via a rolling element, Four moving members arranged between the cams of the cam set and moved by rotation of the cams of the cam set, a moving table fixed to the guide bar, and at least two of the four pairs of cams The selected fine movement XYθ table and a drive means for synchronously rotating in a predetermined direction,
Is provided.

[0006]

According to the present invention, only two of the four pairs of cams, which are in opposition to each other, are synchronously rotated by the driving means so that the distance between the cams moves straight along the X-axis or the Y-axis. , The acting force is transmitted through the moving member and X
The moving table moves along the axis or the Y axis.

Further, when all four pairs of cam sets are synchronously rotated by the driving means in the same direction so that the distance between the cams is rotated with respect to the X axis and the Y axis, the acting force is increased via the moving member. The moving table rotates with respect to the X axis and the Y axis.

[0008]

As described above, according to the present invention, four moving members including a rolling linear guide, a rolling element and a guide bar are provided between the cam pairs of the four rotating cam sets, and the guide bar is mounted on the moving table. The moving table is moved along the X-axis and the Y-axis by rotating the rotating cam.
It can be moved linearly along an axis or rotated about both axes.

[0009]

FIG. 1 shows a bottom view of a moving table according to an embodiment of the present invention. In FIG. 1, reference numeral 10 denotes a moving table, which is supported on the XY plane by a flat guide ball guide or a flat static pressure guide. Moving table 10
Is the X-axis direction shown around the origin at the center,
The linear motion in the Y-axis direction and the rotational motion with respect to the X-axis and the Y-axis are performed.

On the bottom surface of the moving table 10, four guide bars 11 are provided so that the positions thereof coincide with the X axis and the Y axis.
Is fixed. The guide bar 11 has a flat plate shape and is erected on the bottom surface of the moving table 10. Both side surfaces of the guide bar 11 form a rolling linear guide 13 that is arranged in parallel with the guide bar 11 via a rolling element 12. Is engaged.

The linear guide 13 has a rolling element 1 on one side.
2, the guide bar 11 is in contact with the rotary cams C1 to C8 on the opposite surface. Cam C1 to C8
Is, for example, an involute cam, which is attached to a high-rigidity spindle shaft and is separately connected to a drive motor M. Each drive motor M is a pulse motor or a servomotor, and is driven and controlled by a control device using a computer (not shown) to rotate forward and backward.

The eight rotating cams are C1 and C2, C3 and C
4, C5 and C6, C7 and C8 form a pair, and each pair is disposed at each corner of the square. In each pair, when one of the rotary cams, for example, C1 rotates counterclockwise and the other rotary cam C2 rotates clockwise by the same angle, the two cams C and C keep the distance between the cam surfaces constant.
The interval between C1 and C2 moves downward in the figure.

A moving member including a guide bar 11, a rolling element 12, and a rolling linear guide 13 is inserted between the cams C1 and C2, and the moving member moves downward in the figure. As a result, a downward acting force acts on the right side of the moving table 10 fixed to the guide bar 11 in the figure.

Contrary to the above, when C1 is rotated clockwise and C2 is rotated counterclockwise, the distance between the cams C1 and C2 moves upward in the figure. A similar situation occurs with the cam set of cams C5 and C6.

Therefore, when the pair of cams C1 and C2 and the pair of cams C5 and C6 are simultaneously operated in the same manner, the interval between the pair of cams moves vertically in the figure. Then, the moving member moves in the vertical direction in the drawing, and similarly moves the moving table in the vertical direction in the drawing. At this time, the other two cam sets are not operated.

The cams C3 and C4 and the cams C7 and C8 similarly form a cam pair, and move the moving members 11 to 13 and the moving table 10 in the left and right directions in the figure.

On the other hand, four pairs of cams are formed by two pairs of cams C1 and C2 and C5 and C6 along the X-axis.
By moving the pair of cams 2 downward in the drawing and the pair of cams C5 and C6 upward in the drawing, the moving table 10 rotates clockwise. In accordance with this, for the two cam pairs C3 and C4 and C7 and C8 along the Y axis, the C3 and C4 cam pairs may be moved to the left in the figure, and the C7 and C8 cam pairs may be moved to the right in the figure.

In the above embodiment, the rotating cam is an involute cam. However, if the cam can be moved while rotating the cam by a predetermined amount while keeping the interval between the cam pairs constant,
It goes without saying that other characteristic cams may be used.

[Brief description of the drawings]

FIG. 1 is a diagram showing a bottom surface shape according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Moving table 11 Guide bar 12 Rolling element 13 Rolling linear guide C Rotating cam M Motor

Claims (2)

(57) [Claims] The present invention comprises four pairs of cams each having a pair of rotating cams of the same shape and arranged at each corner of a square, and the distances between adjacent ones of these cam sets are equal.
And a cam set arranged such that the distance between opposing members is equal to each other, and the distance between the cams is maintained at a predetermined value when these cams rotate by an equal angle in a predetermined direction. A pair of rolling linear guides in contact with the peripheral surface of the cam, a guide bar disposed between the rolling linear guides via a rolling element, and disposed between the cams of the cam set; Four moving members that move by rotating; a moving table fixed to the guide bar; and driving means for selecting at least two pairs of the four pairs of cams and synchronously rotating in a predetermined direction. XYθ table for small movement. 2. The table according to claim 1, wherein said rotary cam is an involute cam.
θ table.