JPH05312556A - Apparatus for measuring coordinates - Google Patents

Abstract

PURPOSE:To obtain an apparatus for measuring coordinates which reduces the cost and prevents deterioration of precision in measurement and deficiency of the strength of a surface plate. CONSTITUTION:A pair of leg parts 54A and 54C of a support member 54 provided along the opposite side parts of a surface plate 64 are joined by an arm 54B, and one leg part 54A is provided for a right-side Y column 52A of a Y carriage 52. A reference air pad 66 of the leg part 54A is supported movably along one side face of the surface plate 64, while an air pad 70 for a counter force provided movably for the other leg part 54C is biased by a prescribed biasing force onto the other side face of the surface plate 64 by a coned disk spring 69. Moreover, a leaf spring 76 joins a left-side Y column 52B of the Y carriage 52 and the leg part 54C of the support member 54 together, while absorbing the thermal deformation of the support member 54. Accordingly, it is unnecessary to fit a guide member directly to the surface plate 64 and to make a groove for guide by machining directly in the surface plate 64.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate measuring machine, and more particularly to a coordinate measuring machine for measuring a shape of an object to be measured by moving a probe in three directions of X, Y and Z axes.

[0002]

2. Description of the Related Art A three-dimensional coordinate measuring machine measures a shape of an object to be measured by moving a probe in three directions of X, Y and Z axes.
As shown in FIGS. 5 and 6, the three-dimensional coordinate measuring machine includes a Y carriage 10, and the Y carriage 10 is a guide 1.
2 along the Y-axis. That is, the guide 12
Is attached to the surface or side surface of the surface plate 14 via bolts 16, 16, ..., And the air pads 18, 18 of one leg portion 10A of the Y carriage 10 are slidably supported on both sides of the guide 12. ing. In this case, the surface plate 14 is formed with screw holes 14A, 14A ... In which the bolts 16, 16 ...

The other leg 10 of the Y carriage 10
B is provided with an air pad 20, and the other leg 1
OB moves along the surface of the surface plate 14 via the air pad 20. As a result, the Y carriage 10 is moved to the guide 12
Along the Y axis. In the above conventional example, Y
Although the carriage 10 was configured to move along the guide 12, as shown in FIG. 7 and FIG.
A three-dimensional coordinate measuring machine that moves the Y carriage 10 along the groove 22 of is also generally known. The same members as those in FIGS. 5 and 6 are designated by the same reference numerals and the description thereof will be omitted.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
Since 4 is made of granite, screw holes 14A, 14
There is a problem that the processing cost of A ... Or the groove 22 becomes high and the cost of the product cannot be reduced. Also, the guide 12
When attached via the bolts 16, 16 ..., there is a problem that the accuracy is deteriorated due to loosening of the bolts 16, 16 ..., When the groove 22 is machined in the surface plate 14, the surface plate 14 becomes insufficient in strength. There is a problem.

The present invention has been made in view of the above circumstances, and provides a coordinate measuring machine capable of reducing cost and preventing deterioration of accuracy and insufficient strength of a surface plate. With the goal.

[0006]

In order to achieve the above object, the present invention provides a Y carriage having a pair of columns standing at both ends of a measuring table along the surface of the measuring table in the Y-axis direction. In the coordinate measuring machine that moves to, there is provided a pair of legs connected to one side surface and the other side surface of the measurement table and connected by an arm member disposed below the measurement table. A support member provided on one column of the Y carriage, and a reference air pad member provided on one leg of the support member and movably supported along one side surface of the measurement table. A reaction force air pad member movably provided on the other leg of the support member, and a reaction force air pad member that is fixed to the other side surface of the measurement table by absorbing thermal deformation of the support member. A spring member for urging in force, the Y
The other column of the carriage and the other leg of the support member are connected to each other, and a connection member that absorbs thermal deformation of the support member is provided.

[0007]

According to the present invention, the pair of leg portions of the supporting member are arranged on one side surface and the other side surface of the measuring table, and are connected by the arm member arranged below the measuring table, so that one leg portion is connected. On one column of the Y carriage. A reference air pad member was provided on one leg of the support member, and the reference air pad member was movably supported along one side surface of the measurement table.

Further, a reaction force air pad member is movably provided on the other leg portion of the support member, and the spring member absorbs thermal deformation of the support member so that the reaction force air pad member is provided on the other side surface of the measurement table. Energize with a constant energizing force. Further, the connecting member connects the other column of the Y carriage and the other leg of the supporting member and absorbs thermal deformation of the supporting member. Therefore, the reaction force against the measurement table of the reference air pad member is maintained constant by absorbing the thermal deformation of the support member,
It is possible to prevent the other column of the Y carriage connected to the support member from being affected by thermal deformation of the support member.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A coordinate measuring machine according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows an enlarged main part of a coordinate measuring machine 50 according to the present invention, and FIG. 2 shows an A-A arrow view thereof. The coordinate measuring machine 50 includes a Y carriage 52 and a support member 54, and the Y carriage 52 has a right Y column 52A and a left Y column 52B.
The support member 54 has a right leg portion 54A and a left leg portion 54C, and lower ends of the right and left leg portions 54A and 54C are connected by an arm 54B. Arm 54B is a surface plate 6
4 extends along the bottom surface of the right and left legs 54A,
54C are respectively provided upright along the right and left side surfaces of the surface plate 64.

An upper end of a right leg 54A is fixed to a lower end of the right Y column 52A, and a bolt 56A is screwed to an upper end of the right leg 54A. Bolt 56A
A ball 58 is welded to the tip of the. As shown in FIG. 3, the ball 58A is rotatably fitted in the groove 60A, and the groove 60A is formed on the back surface of the vertical air pad 60. Vertical air pad 60 sliding surface 60
A is movably supported along the surface of the right end portion of the surface plate 64.

Further, a bolt 56B is screwed into a substantially central portion of the right leg portion 54A, and a ball 58B is fixed to a tip portion of the bolt 56B. The ball 58B is rotatably fitted in a groove 66A formed on the back surface of the reference air pad 66, and has a sliding surface 66 on the reference air pad 66.
B is movably supported along the right side surface of the surface plate 64.

Further, as shown in FIG. 4, the left leg portion 54C is formed.
A shaft 68 is slidably supported on the shaft 68, and a flange 68A is formed at the tip of the shaft 68.
Shaft 68 between left leg 54C and flange 68A
Is provided with a disc spring 69, and the disc spring 69 biases the flange 68A to the right. A ball 58D is fixed to the flange 68A, and the ball 58D is rotatably fitted in a groove 70A formed on the back surface of the reaction force air pad 70. The sliding surface 70B of the reaction force air pad 70 is movably supported along the left side surface of the surface plate 64.

As described above, since the reaction force air pad 70 is provided on the left side surface of the surface plate 64, the reaction force is applied to the reference air pad 66 provided on the left side surface of the surface plate 64.
Further, since the reaction force air pad 70 is urged by the disc spring 69 toward the left side surface of the surface plate 64, the disc spring 69 moves toward the arm 54B.
Absorbs thermal deformation of the support member 54. Therefore, the reaction force applied to the reference air pad 66 can be kept substantially constant. In this case, the spring constant of the disc spring 69 is set smaller than the spring constant of the reference air pad 66.

A bolt 5 is attached to the lower end of the left Y column 52B.
6C is screwed, and a ball 58C is fixed to the tip of the bolt 56C. The ball 58C is rotatably fitted in a groove 74A formed on the back surface of the vertical air pad 74, and the sliding surface 74B of the vertical air pad 74 is movably supported along the left end of the surface plate 64. Has been done.

An upper end of a leaf spring 76 is attached to the lower end of the left Y column 52B, and the lower end of the leaf spring 76 is connected to the left leg 54C. Therefore, the left leg portion 54C is connected to the left Y column 52B via the leaf spring 76.
It is held in a suspended state. As a result, the arm 54
Since the thermal deformation of the support member 54 such as B is absorbed by the leaf spring 76, the thermal deformation of the support member 54 does not affect the left Y column 52B. Therefore, for example, even if the arm 54B of the support member 54 is thermally deformed, a reaction force due to thermal deformation is not generated in the left Y column 52B.

Further, a read head 78 is provided on the right leg 54A, and the read head 78 reads the Y-axis scale 80, whereby the Y of the Y carriage 52 is read.
The amount of movement in the axial direction is detected. The Y-axis scale 80 is provided on the surface plate 64 so as to face the read head 78.
The surface plate 64 is mounted on the pedestal 84 via the bolts 82, 82 ...

The operation of the coordinate measuring machine according to the present invention thus constructed will be described. First, bolts 56A, 5
Adjust 6B, 56C to adjust the air pads 60, 66, 74
To the proper position. That is, the air pad 6
0, 66, 74 sliding surfaces 60B, 66B, 7 respectively
The distance between 4B and the facing surface of the surface plate 64 is set appropriately. In this case, the reaction force air pad 70 is provided on the left side surface of the surface plate 64 because it is provided on the left side surface of the surface plate 64 and is biased by the disc spring 69 toward the left side surface of the surface plate 64. A reaction force is applied to the reference air pad 66.

As a result, the Y carriage 52 is constrained from moving in the X-axis direction and the Z-axis direction and moves only in the Y-axis direction. In the above-described embodiment, the leaf spring 76 is used for the left Y column 52B.
Although the left leg portion 54C is connected to the left leg portion 54C, the present invention is not limited to this, and another connecting member such as a wire may be used.

[0019]

As described above, according to the coordinate measuring machine of the present invention, the thermal deformation of the supporting member is absorbed to keep the reaction force of the reference air pad member against the measuring table constant and to be connected to the supporting member. It is possible to prevent the other column of the Y carriage that is provided from being affected by thermal deformation of the support member.

Therefore, since it is not necessary to directly attach the guide member to the measurement table or to form the guide groove directly on the measurement table, it is possible to reduce the cost, and further, the accuracy is deteriorated and the strength of the surface plate is insufficient. Can be prevented. Further, since the pair of columns of the Y carriage are connected to the supporting member, the twisting of the pair of columns can be prevented.

[Brief description of drawings]

FIG. 1 is a sectional view of a coordinate measuring machine according to the present invention.

FIG. 2 is a view taken along the line AA of FIG.

FIG. 3 is an enlarged view of a main part of the coordinate measuring machine according to the present invention.

FIG. 4 is an enlarged view of a main part of the coordinate measuring machine according to the present invention.

FIG. 5 is a side view of a conventional coordinate measuring machine.

FIG. 6 is a side view of a conventional coordinate measuring machine.

FIG. 7 is a side view of a conventional coordinate measuring machine.

FIG. 8 is a side view of a conventional coordinate measuring machine.

[Explanation of symbols]

 50 ... Coordinate measuring machine 52 ... Y carriage 52A ... Right side Y column 52B ... Left side Y column 54 ... Support member 54A, 54C ... Leg part 54B ... Arm 64 ... Surface plate 66 ... Reference air pad 69 ... Disc spring 70 ... Air force pad for reaction force 76 ... Leaf spring

Claims (1)

[Claims] 1. A coordinate measuring machine for moving a Y carriage equipped with a pair of columns standing on both ends of a measurement table in the Y-axis direction along the surface of the measurement table, wherein A support member provided on a side surface and provided with a pair of leg portions connected by an arm member disposed below the measurement table, one of the pair of leg portions being provided on one column of the Y carriage. A reference air pad member provided on one leg of the support member and movably supported along one side surface of the measurement table, and movably provided on the other leg of the support member. A reaction force air pad member; a spring member that absorbs thermal deformation of the support member to urge the reaction force air pad member to the other side surface of the measurement table with a constant urging force; While connecting the other leg of the square of the column and the support member, the coordinate measuring machine, characterized by comprising a connecting member for absorbing thermal deformation of the support member.