JPS6029385Y2 - XY moving table - Google Patents

Description

[Detailed description of the invention] This invention has a lower table provided on the base and an upper table provided on the lower table, and these two tables are moved by feed screws in directions perpendicular to each other. This is an XY moving table that is capable of moving the upper table, and the feed screw that moves the upper table is supported by the base, and a connection mechanism with a degree of freedom is interposed between the nut screwed onto the feed screw and the upper table. The present invention relates to an XY moving table that enables accurate movement of an upper table corresponding to the rotational displacement of a screw.

A lower table supported by a first guiding means provided on the base and movable in one direction, and a second guiding means provided on the lower table move in a direction perpendicular to the moving direction of the lower table. It has a movable upper table,
The XY moving table in which the respective tables are moved by feed screws generally has a feed screw that moves the lower table supported on the base, and a feed screw that moves the upper table supported on the lower table. However, in this type of Y-moving table, the motor, which is the power source for driving the upper table, is attached to the table, so the weight of the lower table increases and the inertia of the lower table increases. There was a drawback that it was difficult to move the table at high speed.

Further, in the case where the motor is attached to the lower table, there is a drawback that the table vibrates due to vibrations generated by the motor, and the table does not stabilize immediately even if the motor is stopped.

An XY moving table that eliminates these drawbacks has a feed screw that moves the upper table supported on the base, and a pair of guide rollers installed on a sliding block screwed onto the feed screw to control the direction of movement of the upper table. An XY moving table is known that has one end bent and held between guide rollers.

However, since this XY moving table uses a sliding block, if there is eccentricity in the feed screw or in the part that supports the feed screw, the nut will run out, and the surface pressure applied to the sliding surface of the sliding block will change. Therefore, the sliding resistance of the sliding block changes, making it difficult to accurately position the table.

This idea was created by focusing on the above-mentioned drawbacks of the conventional XY moving table, and its purpose is to enable high-speed movement of the table and prevent eccentricity of the feed screw or the part that supports the feed screw. To provide an XY moving table capable of accurately positioning the table even if there is some eccentricity.

To achieve this objective distantly, this invention supports a feed screw that moves the upper table on a base, and attaches a pair of guide surfaces perpendicular to the axial direction of the feed screw to either the nut or the upper table. A first connecting part in which an arm having rollers at both ends that engage with this guide surface is swingably attached to the other member, and a pair of guide surfaces parallel to the axial direction of the feed screw are connected to a nut or A second connecting part is provided on either the base or the base member, and an arm having rollers at both ends that engage with this guide surface is swingably attached to the other member, and the elasticity of each arm is Due to the deformation, each of the guide surfaces is preloaded by two rollers, thereby making it possible to accurately position the upper table in accordance with the rotation of the feed screw.

Next, embodiments of this invention will be described with reference to the drawings.

The lower table 1 is supported by two sets of first guide means 3 provided on a base 2 and is movable in one direction.

This first guide means 3 uses a cross roller linear motion guide in which rollers 6 whose axis directions are alternately changed at right angles are arranged between two guide blocks 4 and 5, but other types of guides are used. It may also be a guide means.

The upper table 7 has two sets of second
The lower table 1 is supported by a guide means 8 and is movable in a direction perpendicular to the direction of movement of the lower table 1.

This second guide means 8 comprises two guide blocks 9, 10
A cross-roller linear motion guide is used in which rollers 11 whose axes are alternately oriented at right angles are disposed therebetween, but other types of guide means may be used.

The feed screw 12 has an axis parallel to the moving direction of the upper table 7, and is rotatably supported by two bearings 15 and 16 fitted into a bearing 13 and a bracket 14.

A coupling 17 is attached to the end of the feed screw 12, and the shaft of a motor 19, which is attached to the bracket 14 via a spacer 18, is coupled to the feed screw 12 through the coupling 17.

The nut 20 is screwed onto the feed screw 12 and is movable in the axial direction of the feed screw 12 as the feed screw 12 rotates.

A first connection part is provided between the upper table 7 and the nut 20 for reliably transmitting the displacement of the nut 20 to the upper table 7, and a first connection part is provided between the nut 20 and the base 2.
A second connection is provided which prevents rotation of the lead screw 12 relative to the lead screw 12.

In this first connection, a rail 23 having guide surfaces 21 and 22 that are parallel and opposite to each other and back to back is fixed to the upper table 7 with bolts 24 so that the guide surfaces are perpendicular to the axis of the feed screw 12. , the guide surface 2 is on the top surface of the nut 20.
1. Support shafts 25 and 26 spaced apart in the axial direction of the feed screw 12 are fixed to each other, and the guide surface 2 is attached to the support shafts 25.
An arm 28 having a rotatable roller 27 at both ends that engages with the guide surface 22 is fitted in a swingable manner to the support shaft 26.
An arm 30 having rotatable rollers 29 at both ends that engage with the arm 30 is fitted in a swingable manner, and the pair of rollers 27 and 29 are pressed against the guide surfaces 21 and 22 from opposite directions. There is.

From the distance between the center of the support shaft 25 and the center of the support shaft 26, the support shaft 25
the distance in a free state from the center of the roller to the common tangent of the two rollers 27 on the side where the roller 27 contacts the guide surface 21
The dimension obtained by subtracting the distance in the free state from the center of the support shaft 26 to the common tangent line of the two rollers 29 on the side where the roller 29 contacts the guide surface 22 is the guide surface 21.2 of the rail 23.
2, the rail 23 elastically deforms the arms 28, 30 and the opposite roller 2.
The rollers 27 and 2 are in a state where the distance between them is expanded.
It is assembled between 9 and 9.

For this purpose, the rollers 27, 29 are always engaged in a prestressed state on the guide surface 21.22 due to the elastic deformation of the arms 28.30.

The arms 28 and 30 have rollers 27 and 39 on the guide surface 21.
．． 22 with an appropriate preload, a notch 31 or 3 is provided.
2 is provided, but other means for obtaining appropriate elasticity may be used.

The second connection connects the key 35 with the bolt 36 to the base 2 in such a way that the guide surfaces 33 and 34 are parallel and opposite to each other and back to back.
Support shafts 37 and 38 that correspond to the guide surfaces 33 and 34 and are spaced apart in a direction perpendicular to the axial direction of the feed screw 12 are fixed to the lower surface of the nut 20. An arm 40 having rotatable rollers 39 at both ends to be engaged is fitted in a swingable manner, and an arm 42 having rotatable rollers 41 at both ends to engage with the guide surface 34 is rocked to the support shaft 38. The pair of rollers 39 are freely fitted together.
and 41 are pressed against the guide surfaces 33 and 34 from opposite directions.

From the distance between the centers of the support shaft 37 and the center of the support shaft 38, the support shaft 37
the distance in a free state from the center of the roller to the common tangent of the two rollers 29 on the side where the roller 39 contacts the guide surface 33;
The dimension obtained by subtracting the distance in the free state from the center of the support shaft 38 to the common tangent line of the two rollers 41 on the side where the roller 41 contacts the guide surface 34 is the same as that of the first connection portion.

For this reason, the rollers 39, 41 are always engaged in a prestressed state with the guide surfaces 33, 34 due to the elastic deformation of the arms 40.42.

The arm 40.42 is provided with a notch 43 or 44 to give the arm 40.42 appropriate elasticity.

The motor 45 that drives the lower table 1 is only shown as being fixed to the base 2.

The XY moving table of this invention constructed as described above has a structure in which the motor 19 that drives the upper table 7 is fixed to the base 2, so there is no need to provide the lower table 1 with a mechanism that drives the upper table 7. Since the inertia of the lower table 1 does not increase, the operation of the lower table 1 can be made faster. Also, since the motor 19 is supported by the base 2, the table will vibrate due to the vibration of the motor, and the stabilization time of the table will be reduced. It is possible to obtain an XY moving table that does not increase the number of XY moving tables. A second connection part having a degree of freedom in a direction parallel to the axis of the screw 12 is provided between the nut 20 and the base 2, and each of the connection parts is engaged by a preloaded roller. Therefore, even if there is slight wobbling of the nut, the positioning accuracy of the table is less likely to be hindered, and an XY moving table capable of accurate positioning can be obtained.

Furthermore, since rollers that engage with the guide surfaces of the connecting parts are provided at both ends of the arm, the rigidity of the engaging parts is high.
In addition, since the preload force applied to the roller utilizes elastic deformation using the arms as double-supported beams, the spring constant can be reduced, and fluctuations in the preload force due to processing errors during manufacturing are small, making it possible to easily manufacture uniform products. It has this effect.

In this embodiment, a guide surface 21.22 is provided on the side of the upper table 7.
, and the support shafts 25 and 26 are provided on the side of the nut 20.
and a guide surface 33, 34 is provided on the side of the base 2,
Although the second connection section is shown in which the support shafts 37 and 38 are provided on the side of the nut 20, the first connection section is provided with support shafts 25 and 26 on the side of the upper table 7, and the support shafts 37 and 38 are provided on the side of the nut 20. The second connecting portion may have a support shaft 37.38 on the base 2 side and a guide surface 33.34 on the nut 20 side. The same effects can be obtained in both cases.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the XY moving table of this invention, FIG. 2 is a right side view of FIG. 1, and FIG.
4 is a sectional view taken along line AA in the figure, and FIG. 4 is a sectional view taken along line BB in FIG. 1...Lower table, 2...Base, 7
...Top table, 12...Feed screw,
20... Natsu, 21.22, 33.34...
...Guidance surface, 25.26°37.38...
Support shaft, 27, 29, 39.41...Roller, 2
8, 30, 40, 42...Arm.

Claims (1)

[Scope of utility model registration request] a lower table 1 supported by a first guide means 3 provided on a base 2 and movable in one direction;
an upper table 7 supported by a second guide means 8 provided at the base 2 and movable in a direction perpendicular to the moving direction of the lower table 1;
A feed screw 12 rotatably supported by a feed screw 12, a nut 20 screwed onto the feed screw, a first connecting portion provided between the nut 20 and the upper table 7, and a first connecting portion between the nut 20 and the base 2. The first connecting portion is provided on either the nut 20 or the upper table 7 and is perpendicular to the axis of the feed screw 12 and parallel and opposite to each other. A pair of guide surfaces 21.22 are placed back to back, and a pair of guide surfaces 21.22 is fixed to the nut 20 or the other member of the upper table 7 at a distance from each other in the axial direction of the feed screw 12 in correspondence with each of the guide surfaces 21.22. and two arms having rotatable rollers 27 and 29 at both ends, which are swingably fitted into the respective support shafts and engaged with the guide surfaces 21 and 22, respectively. 28.30
The second connecting portion includes a pair of guide surfaces 33 that are provided on either the nut 20 or the base 2 and are parallel to the axis of the feed screw 12 and are parallel and opposite to each other, back to back. .34 and two support shafts 37 and 38 which correspond to the guide surfaces 33 and 34 and are fixed to the nut 20 or the other member of the base 2 in a spaced manner in a direction orthogonal to the axial direction of the feed screw 12; , two arms 40 and 42 having rotatable rollers 39 and 41 at both ends, which are swingably fitted to each of the support shafts and engaged with each of the guide surfaces 33 and 34, The arms 28, 30
, 40. Due to the elastic deformation of 42, the pair of rollers 27°2
9, 39, and 41 respectively approach the guide surface 21 from opposite directions.
22, 33, and 34.
Y moving table.