JPH044168Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention consists of a detector supported by the main body and a Y
The present invention relates to an improvement in a movable table measuring machine that measures the dimensions of an object by involving the object attached to a table supported movably in the axial direction.

[Background technology and its problems]

Measuring machines are known that measure the dimensions, shape, etc. of a measuring object by moving a detector such as a touch signal probe or a video camera relative to the object to be measured in one or more axial directions while involving the two. There are various types of methods, such as two-dimensional measuring machines, three-dimensional measuring machines, digital contracers, inner and outer diameter measuring machines, etc.

In such a measuring machine, for example, the X, Y, and Z of a three-dimensional measuring machine are There is a movable table type in which a table on which an object to be measured is attached can be moved in one axis direction, such as the Y-axis direction.

The conventional structure of this movable table measuring machine is that the table is supported by rotating rollers on the horizontal sliding surface of the main body, and the main body has a V-shaped sliding surface and a corresponding V-shaped groove is provided on the table side for engagement. Things such as guides were popular.

However, the conventional structure described above not only has a large sliding resistance, which increases the driving power, but also has the disadvantage that it is difficult to process rotating rollers, V-shaped grooves, etc., increasing the economic burden and resulting in poor measurement accuracy. It was hot. By the way, in order to reduce the sliding resistance, it is possible to move the main body and the table by interposing a so-called air bearing, but the main problem is that the air bearing can cause positional fluctuations in the direction orthogonal to the direction of movement of the table. It has not been used in high-precision measuring instruments because of problems such as decreased accuracy and unstable accuracy due to the floating height of the table.

[Purpose of invention]

The present invention was devised in view of the above-mentioned conventional problems, and its purpose is to provide a movable table measuring machine that reduces sliding resistance and ensures high precision measurement.

[Means and effects for solving the problem] In the present invention, the position of the table is regulated in the direction (X-axis direction) orthogonal to the direction of movement (Y-axis direction) by a pair of air bearings, and the direction ( Z
In the axial direction, the position is regulated by a pair of air bearings, and in order to prevent the floating of the air bearings and fluctuations in the flying height, a table floating prevention means using magnets is provided to eliminate the above-mentioned conventional problems.

For this reason, in a movable table measuring machine that measures the dimensions of an object by involving a detector supported by the main body and an object attached to a table supported movably in the Y-axis direction by the main body, , the main body is provided with a pair of Y guide rails extending in the Y-axis direction, and includes a pair of air bearings that engage with the side end surfaces of each Y-guide rail and are oriented in opposite directions to each other in the X-axis direction. An X-axis position regulating means formed to regulate the position in the X-axis direction with respect to the main body is provided, and
A Z-shape includes a pair of air bearings each engaging the upper end surface of a guide rail and oriented in the same direction in the Z-axis direction, and is formed to regulate the position of the table relative to the main body in the Z-axis direction.
Table floating prevention means is provided with an axial position regulating means and includes a magnet acting on a magnetic portion of the main body attached to the table, and is formed to prevent the table from rising in the Z-axis direction with respect to the main body. The position of the table relative to the main body in the X-axis and Z-axis directions can be controlled to be constant regardless of variations in the weight of the object to be measured attached to the table and/or the air pressure supplied to both the position regulating means. This structure achieves the above purpose.

Therefore, the position in the X-axis direction is regulated by an X-axis position regulating means consisting of a pair of air bearings oriented in opposite directions on the side end surface of each Y guide rail, and the position in the Z-axis direction is regulated by , are regulated by Z-axis direction position regulating means consisting of a pair of air bearings that respectively engage the upper end surfaces of each Y guide rail in the same direction. Furthermore, the position in the Z-axis direction is
The table floating prevention means prevents the table from floating due to the Z-axis direction position regulating means, thereby ensuring position regulation.

Here, even if the weight of the object to be measured attached to the table or the air pressure supplied to each air bearing fluctuates, the position in the X-axis and Z-axis directions can be accurately regulated, thereby reducing sliding resistance. It is possible to guarantee high precision measurement while maintaining small size and smooth operation.

〔Example〕

An embodiment of the movable table measuring machine according to the present invention will be described with reference to the drawings.

The measuring machine in this embodiment is a three-dimensional measuring machine, and this three-dimensional measuring machine is constructed as a whole as shown in FIG.

That is, the base 3 is installed on the base 1. This base 3 has a pair of supports 25 in the X-axis direction,
25 is erected with its base end 27 fixed. A cross beam member 30 extending in the X-axis direction is spanned between the pillars 25, 25, and a Z guide box 40 is integrally provided on the X slider 35 which is movable along the cross beam member 30. . A spindle 4 having a detector 42 serving as a video camera at its tip
1 is supported by a Z guide box 40 so as to be slidable in the Z-axis direction. Here, base 3, pillars 25, 2
5. The main body 100 is composed of the cross beam member 30, the X slider 35, and the Z guide box 40, and the moving mechanism for the detector 42 is configured to move the detector 42 in the X-axis direction and the Z-axis direction. . on the other hand,
The table 20 is movable in the Y-axis direction and the base 3
is supported by Therefore, the object to be measured (not shown) placed on the table 20 and the detector 42 are movable relative to each other in three-dimensional directions.

In addition, the base 3 is provided with a recess 5 having a U-shaped cross section and distributed in the center along the Y-axis direction.
Inside the recess 5, an X-axis position regulating means 50, a Z-axis position regulating means 60, a Y-axis displacement detecting means (not shown), a driving means 80, etc., which will be described later, are accommodated. Furthermore, the bellows 92a and 92b form a dustproof device 90. Note that electronic parts such as a data processing device are not shown.

As seen in FIG. 1, which is based on the - arrow line in FIG. 7 is provided. In addition, 1
Numerals 7 and 17 are adjustment bolts for correcting the posture of the base 3 with respect to the base 1. Y guide rails 38, 38, which are centered in the X-axis direction, are provided on the intermediate floor portion 4 of the base 3 along the Y-axis direction, and are fixed by bolts 8, 8. Y guide rail 3
The cross section of 8 is a rectangular parallelepiped, and each surface 29, 39 is finished smooth. Therefore, the table 20 is formed to be positioned based on the upper end surface 29 and side end surface 39 of the Y guide rails 38, 38. And base end portions 27, 27 of the struts 25, 25.
are fixed bolts 26, 26 to secure the upright parts 7, 7 of the base 3.
are fixed to the upper end surface of each. As a result, the height of the supports 25, 25 is higher than the base end 2 of the Y guide rails 38, 38 that guide the table 20.
Since 7 and 27 are at high positions, they can be shortened.

Now, the Z-axis position regulating means 60 is
A pair of air bearings 6 oriented in the same direction (downward in the Z-axis direction in the figure) provided on the lower end surface 22 of the
1 and 61, an intermediate floor portion 4 which is a magnetic part of the base 3 which is the main body 100, and a table floating prevention means 66 which includes a magnet 62 attached to the table 20 which acts as an attraction. The air bearings 61, 61 are supplied with compressed air from an air source (not shown), and the table 20 is levitated by several μm to several + μm by jetting the air onto the upper end surfaces 29, 29 of the Y guide rails 38, 38. This allows the table 20 to move in the Y-axis direction while regulating its position in the Z-axis direction.
It should be noted that the magnets 62, 62 are arranged with centers distributed in the X-axis direction. Here, table 2
When the table 20 is small and lightweight, or considering the weight of the measurement object (not shown) to be placed,
A magnet 62 which attracts the intermediate floor portion 4, which is a magnetic material portion, is provided as a table floating prevention means 66 for pulling the table downward in FIG. The magnet 62 is adjusted in the height direction with an adjustment bolt 64, and the mounting bolt 6 is adjusted so that it has a minute clearance with the top surface of the flattened intermediate floor 4.
5 and is fixed to the table 20. Note that the magnet 62 is fixed to the table 20 via a magnetic body 63 in order to improve magnetic efficiency. Therefore, the table 20 is formed so that its position in the Z-axis direction is regulated by the balance between the downward attractive force caused by the magnetic force of the table floating prevention means 66 and the air pressure of the air bearing 61 that resists this force. . In addition,
The magnet 62 is attached to the table 20 through a non-magnetic material 67 in addition to a magnetic material 63.
This is to prevent leakage of magnetic force.

On the other hand, the X-axis direction position regulating means 50 is formed of air bearings 51, 51 which are oriented in opposite directions and correspond to the respective side end surfaces 39, 39 of the respective Y guide rails 38, 38.
1 and 51, the clearance thereof can be adjusted by adjustment bolts 53 and 53 while ensuring freedom of posture through balls 52 and 52.

Further, the driving means 80 is for automatically moving the table 20 in the Y-axis direction, and includes a ball screw 81 rotatably supported by a support stand 83 fixed to the base 3, and a ball screw 81 screwed into the ball screw 81. Nut member 82 that is assembled and attached to table 20
and a motor (not shown).

Furthermore, Y-axis displacement detection means (not shown) including a main scale extending in the Y-axis direction and a corresponding index scale is provided at the center of the base 3 in the X-axis direction.

Note that the dustproof device 90 includes a bellows device 91 and a dustproof cover 101. This bellows device 9
1 is the first bellows 9, as is clear from FIG.
2a and a second bellows 92b, the first bellows 9
2a is stretched between one end of the table 20 in the Y-axis direction and one end of the base 3. The second bellows 92b also corresponds to the base 3 on the other end side of the table 20 in the Y-axis direction.
Similarly to the first bellows 92a, it is stretched between the other end side. Therefore, both bellows 92a, 92b are
Each of them can expand and contract as the table 20 moves in the Y-axis direction, and the recess 5 of the base 3 on which each means is disposed can be closed. Further, the dustproof covers 101, 101 are fixed to the base 3 via the support members 11, 11, and their tip sides can be inserted into recesses 21 provided on each side of the table 20, respectively. Therefore, the width equivalent to the table 20 is determined by the bellows device 91, and the width of the table 20 is
The recessed portion 5 of the base 3 can be closed by the dustproof covers 101, 101 with respect to the gap in the X-axis direction between the raised portion 7 of the base 3 and the raised portion 7 of the base 3. Of course, both ends of the base 3 in the Y-axis direction are attached to the bellows mounting plates 94, 94.
is blocked by. Recess 12 of support member 11
Rubber 13 is pasted to accommodate tools.

Note that a position detection means 110 formed from a limit switch 111 attached to the base 3 and an engagement member 112 attached to the table 20 detects the limit position of the table 20 in the Y-axis direction.

In the coordinate measuring machine configured in this way, a measurement target (not shown) placed on the table 20
While relatively moving the detector 42 and the detector 42 in three-dimensional directions, the dimensions of the object to be measured can be measured with high precision by using output signals from a Y-axis displacement detecting means (not shown) or the like.

Here, the table 20 is moved in the Y-axis direction by rotating the ball screw 81 of the drive means 80 with a motor (not shown). The position of the table 20 in the X-axis direction is regulated by the X-axis position regulating means 50, 50 whose clearance is adjusted in advance, while the position of the table 20 in the X-axis direction is regulated by the Z-axis position regulating means 60, 6.
0 by the upper end surface 2 of the Y guide rails 38, 38
9 and 29, the Z-axis direction position is restricted. Therefore, the table 20, that is, the object to be measured placed on the table 20, is positioned in the X and Z axes while being regulated in the Y direction.
is moved in the axial direction.

During this movement in the Y-axis direction, the bellows 92a and 92b expand and contract as the table 20 moves without floating, and cover the X-axis position regulating means 50, Z-axis position regulating means 60, etc. accommodated in the recess 5. Dustproof. Furthermore, since the clearance in the X-axis direction between the table 20 and the base 3 is covered by the dustproof covers 101, 101, reliable dustproofing is achieved.

According to this embodiment, the base 3 is provided with a recess 5 for sorting, and the Y guide rails 38, 38 are provided in the recess 5.
and position regulating means 50, 60, Y
Shaft displacement detection means (not shown) and drive means 80
etc., the height of the table 20 in the Z-axis direction can be lowered, that is, the supports 25, 25 can be attached to the base 3 at a higher position. As a result, pillar 2
Since the detectors 5 and 25 can be made shorter in size, they can be made smaller and lighter and/or more rigid, and the position of the detector 42 can be made immovable to achieve high precision measurement.

The Z-axis position regulating means 60 is composed of air bearings 61, 61 and table floating prevention means 66, 66 using magnets 62, 62 that bias the table 20 downward against the air bearings 61, 61. Even if the table 20 is lightweight or the measurement object to be placed is lightweight, the position of the table 20 in the Z-axis direction can be accurately regulated without making minute adjustments to the air supplied to the air bearings 61, 61. . That is, the table floating prevention means 66, 66 prevent the table 20 from moving as shown in the figure by attracting the magnet 62 attached to the table 20 to the intermediate floor 4, which is the magnetic part of the base 3, which is the main body 100. The air bearing 61, which is forcibly pulled downward, regulates the position in the Z-axis direction by balancing the force that causes the table 20 to float upward in the figure against the upper end surface 29 of the Y guide rail 38. In this case, the magnet 62 is the magnetic body 6
Since it is attached to the table 20 via 3,
Since the magnetic force of the magnet 62 is magnified with respect to the intermediate floor portion 4, it acts effectively and can increase the attraction effect. Furthermore, since the magnets 62 are arranged at equal distances from the center in the X-axis direction (distributed to the center in the X-axis direction), the table 20 is not unbalanced and the top surface of the table 20 can be maintained horizontally, which is effective. The position in the Z-axis direction can be kept constant throughout the measurement range, ensuring high precision measurement.

In addition, since the X-axis position regulating means 50 consists of a pair of air bearings 51, 51 oriented in opposite directions to each side end surface 39, 39 of the Y guide rails 38, 38, each air bearing 51 is oriented in opposite directions.
1 and 51 from the same air source, even if the air pressure fluctuates, the position of the table 20 in the X-axis direction will not shift. Therefore,
The position in the X-axis direction can be kept constant throughout the effective measurement range, ensuring high precision measurement.
Further, since the Y guide rails 38, 38 extend in the Y-axis direction, meandering of the table 20 does not occur.

Furthermore, since the X-axis position regulating means 50 and the Y-axis position regulating means 60 are air bearings, smooth running of the table 20 can be achieved with small sliding resistance.

Furthermore, each means 50, 60, 80 of the base 3
Since the dustproof device 90 is provided to cover the recess 5 in which the device is accommodated, not only can the characteristics and functions of these devices be stably maintained, but also safe work can be ensured.

Furthermore, since the ball screw 81 of the driving means 80 and the nut member 92 are screwed together at the center of the table 20, this together with the function of the X-axis position regulating means 50 prevents rattling and meandering. At the same time, the table 20 can be moved linearly in the Y-axis direction. High precision measurement can also be guaranteed from this point of view.

In the above embodiment, the detector 42 is a video camera, but it may be a touch signal probe or the like, and its type is not limited. Further, the X slider 35, spindle 41, etc. may be of a motor feeding type or a manual feeding type. Of course, the measuring machine is not limited to the above-mentioned three-dimensional measuring machine, but may be a two-dimensional measuring machine, an inner/outer diameter measuring machine, a digital contourer, etc., as long as it has a movable table, and any model can be used.

[Effect of idea]

As is clear from the above explanation, the present invention reduces sliding resistance, and even if there are pressure fluctuations in the air supplied to the air bearing or changes in the weight of the object to be measured,
This has an excellent effect in that it is possible to perform high-precision measurement while accurately regulating the positions of the axes and the Z-axis while maintaining smooth movement of the table.

[Brief explanation of drawings]

Fig. 1 is a front view (based on the - arrow line in Fig. 2) showing an embodiment of a movable table measuring machine according to the present invention, and Fig. 2 is an overall view of the same when the measuring machine is a three-dimensional measuring machine. FIG. 3... base, 5... recess, 20... table,
42...Detector, 50...X-axis direction position regulating means, 51, 61...Air bearing, 60...Z
Axial position regulating means, 62... Magnet, 63
...Magnetic material, 66...Table floating prevention means, 6
7... Non-magnetic material, 80... Drive means, 90... Dust-proof device, 91... Bellows device, 101... Dust-proof cover.

Claims (1)

[Claims for Utility Model Registration] (1) Dimensions, etc. of an object to be measured by involving a detector supported by the main body and an object to be measured attached to a table supported movably in the Y-axis direction by the main body. In a movable table measuring machine for measuring, the main body is provided with a pair of Y guide rails extending in the Y-axis direction, and the pair of Y guide rails are engaged with the side end surfaces of each Y-guide rail and are oriented in opposite directions to each other in the X-axis direction. An X-axis position regulating means is provided, which includes an air bearing and is formed to regulate the position of the table relative to the main body in the X-axis direction, and is engaged with the upper end surface of each Y guide rail, and a magnetic body of the main body attached to the table; and a Z-axis position regulating means formed to regulate the position of the table relative to the main body in the Z-axis direction, including a pair of air bearings oriented in the same direction. A table floating prevention means including a magnet acting on a portion of the table and configured to prevent the table from floating in the Z-axis direction with respect to the main body is provided, and the table float prevention means is configured to restrict the weight and/or the position of the object to be measured attached to the table. 1. A movable table measuring instrument, characterized in that the position of the table relative to the main body in the X-axis and Z-axis directions can be controlled to be constant regardless of fluctuations in the air pressure supplied to the means. (2) The movable table measuring instrument according to claim 1 of the utility model registration, characterized in that the magnet of the floating prevention means is fixed to the table via a non-magnetic material. (3) In claim 1 or 2 of the utility model registration claim, the magnet of the floating prevention means is attached to the table so that its position in the Z-axis direction can be changed with respect to the magnetic part of the main body. A movable table measuring machine.