JPH06226571A - Table moving device of machine tool - Google Patents

Abstract

PURPOSE:To surely avoid interference with another machine tool at taking out a ball screw, and exchange the ball screw or a nut member simply and efficiently. CONSTITUTION:The table moving device 14 is provided with a table 20 loaded with a working unit 18 containing a tool 16, guide rails 22a-22c for guiding the table 20, a supporting part 24 provided on the table 20, a nut member 26 fitted to the supporting part 24, and a ball screw 28 which is threadedly engaged with the nut member 26 and arranged outside the guide rails 22a-22c together with the nut member 26.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a table movement in a machine tool in which a table on which a machining unit including a tool is placed is movable back and forth under the guide action of a guide rail via a ball screw and a nut member. Regarding the device.

[0002]

2. Description of the Related Art Normally, a machining unit constituting a machine tool is mounted on a table which is movable along two or more guide rails provided on a base, and the table moves in a predetermined direction. At the same time, the spindle provided in the processing unit is rotated to perform a desired processing operation on the work.

A ball screw connected to a rotary drive source is widely used as a moving device for moving the table. The ball screw is arranged between two or more guide rails, and is configured so that the ball screw is screwed into a nut member fixed to the lower portion of the table.

[0004]

By the way, if the above moving device is frequently used, a part of the ball screw or the nut member is likely to be worn, and it is necessary to replace the ball screw or the nut member. Become. However, in the above-mentioned prior art, since the ball screw is arranged between two or more guide rails, this ball screw must be taken out in the axial direction. It has been pointed out that when another machine tool is arranged adjacent to the machine tool, it interferes with the machine tool and cannot be taken out. Therefore, conventionally, the ball screw and / or the nut member is replaced with the table on which the processing unit is placed being lifted, which is complicated and inefficient. There is a problem.

The present invention solves this kind of problem, and it is possible to reliably avoid interference with other machine tools when taking out the ball screw, and to simplify the ball screw and nut members. An object of the present invention is to provide a table moving device in a machine tool that can be efficiently replaced.

[0006]

In order to achieve the above object, the present invention provides two or more means for supporting a table on which a machining unit including a tool is mounted and guiding the table in a predetermined direction. Guide rails, a support portion that is provided on the table so as to project to the outside of the two or more guide rails, a nut member that is attached to the support portion, And a ball screw which is arranged along the guide rails and is screwed into the nut member to move the table along the two or more guide rails.

Further, it is preferable that the table includes a linear movement guide roller bearing that engages with the two or more guide rails.

[0008]

In the table moving device for a machine tool according to the present invention described above, the two or more guide rails for supporting the table are provided with the supporting portions projecting outward, and the nut member attached to the supporting portions is attached to the supporting members. Has a ball screw arranged outside the two or more guide rails. Therefore, the ball screw and the nut member are located outside the guide rail, and the ball screw and the nut member can be taken out in a direction intersecting the axial direction of the ball screw. As a result, even if a particularly long ball screw is used, another machine tool or the like can be arranged close to the axial direction thereof.

Further, when a linear movement guide roller bearing that engages with two or more guide rails is used, even if the ball screw is arranged outside of the two or more guide rails, the table can be smoothly and smoothly raised. It can be moved with precision.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A table moving device for a machine tool according to the present invention will be described below with reference to the accompanying drawings.

1 to 3, reference numeral 10 indicates
1 shows a machine tool incorporating a table moving device according to the present embodiment. The machine tool 10 includes a base 12, and a table moving device 14 according to the present embodiment is provided on the base 12.

The table moving device 14 supports a table 20 on which a processing unit 18 including a tool 16 is placed, and three guide rails 22a to 22c for guiding the table 20 in a predetermined direction, A support portion 24 provided on the table 20 so as to project outward from the guide rails 22a to 22c, a nut member 26 attached to the support portion 24 via a plurality of fixing bolts 25, and the guide rails 22a to 22a. A ball screw 28 which is disposed outside the guide rails 22c along the guide rails 22a to 22c, and which is screwed into the nut member 26 to move the table 20 along the guide rails 22a to 22c. Equipped with.

The guide rails 22a to 22c are indicated by arrows X.
The guide rails 22a to 22c.
The ball screw 28 extending in the direction of the arrow X in parallel with is rotatably supported by a fixed bearing 30 fixed at one end on the base 12, and the other end is fixed at the first end on the base 12. It is connected to the servo motor 32 (see FIG. 2).

On the lower side of the table 20, two linear movement guide roller bearings 34a to 34c which engage with the guide rails 22a to 22c are mounted. The roller bearings 34a to 34c may be of any type as long as they can smoothly move the table 20 in the direction of the arrow X, and are disclosed in, for example, JP-A-57-101121 and JP-A-58-81215. You can use what has been done.

On the table 20, rail members 36a and 36b extending in the arrow Z direction intersecting with the arrow X direction and the second rail members 36a and 36b are provided.
A ball screw 40 fixedly attached to the servo motor 38 and connected to the second servo motor 38 to extend in the arrow Z direction.
, But is screwed into a nut member (not shown) fixed to the Z table 42. A vertically long column 44 is placed on the Z table 42, and an elevating motor 46 is fixed to an upper portion of the column 44 in a vertically downward direction.

A Y table 50 is engaged with a ball screw 48 which is connected to the lifting motor 46 and extends downward, and the processing unit 18 is mounted on the Y table 50 via a turning motor 51 so as to be screwed. To be done. The tool 1 is attached to the spindle 52 extending forward from the processing unit 18.
6 is attached, and the tool 16 is positioned in a predetermined posture with respect to the work W positioned and fixed on the work table 54.

Next, the operation of the table moving device 14 thus constructed will be described in connection with the machine tool 10 incorporating the same.

First, the work W is positioned and held on the work table 54, and the predetermined tool 16 is mounted on the spindle 52 of the processing unit 18. Therefore, the tool 16 is positioned corresponding to the processed portion of the work W. That is, the ball screw 2 is operated under the action of the first servo motor 32 that constitutes the table moving device 14 according to the present embodiment.
8 is rotated, and the table 20 provided with the nut member 26 screwed to the ball screw 28 moves in the arrow X direction under the guiding action of the guide rails 22a to 22c and the roller bearings 34a to 34c. Further, the ball screw 40 is rotated under the action of the second servo motor 38, and the Z table 42 is moved by the arrow Z under the action of guiding the rail members 36a and 36b.
Direction, which positions the column 44 in the X and Z directions.

On the other hand, the lifting motor 46 is driven to rotate the ball screw 48, the Y table 50 is moved in the vertical direction, and the machining unit 18 is swung under the action of the swivel motor 51. The tool 16 is rotated under the action of. Therefore, the tool 16 is the work W
Automatically perform a predetermined processing operation.

By the way, when the table moving device 14 is frequently used, a part of the ball screw 28 for moving the table 20 in the direction of the arrow X and the nut member 26 are likely to be worn, and the ball screw 28 and the nut member are easily worn. 26
Need to be replaced. In this case, in this embodiment, the ball screw 28 and the nut member 26 are the guide rail 22.
It is arranged outside a to 22c. Therefore, the fixing bolt 25 that fixes the nut member 26 to the support portion 24 of the table 20 is loosened, and the fixed bearing 30 and the first servomotor 32 are removed from the base 12, and then the ball screw 28, The nut member 26, the fixed bearing 30, and the first servomotor 32 are integrally taken out in the arrow Z direction.

Therefore, in this embodiment, the considerably long ball screw 28 can be taken out in the direction (the arrow Z direction) intersecting the axial direction (the arrow X direction), and especially the other machine screw 10 can be taken out. When the machine tools 10 are arranged adjacent to each other in the arrow X direction, the ball screw 28 does not interfere with the other machine tools 10. As a result, it is possible to arrange the plurality of machine tools 10 close to each other in the arrow X direction, and it is possible to easily and efficiently replace the long ball screw 28 and the nut member 26. can get.

Further, in this embodiment, the ball screw 28 is arranged outside the guide rails 22a to 22c.
By providing the table 20 with the roller bearings 34a to 34c that engage with the guide rails 22a to 22c, the table 20 can be moved smoothly and highly accurately in the arrow X direction.

That is, as shown in FIG. 4, an experimental machine tool 10a is prepared. The machine tool 10a has the same configuration as the machine tool 10 described above, and the same components are designated by the same reference numerals and detailed description thereof will be omitted.

In the machine tool 10a, as shown by the chain double-dashed line in FIG. 4, a table moving device 14a having a ball screw 28 arranged between guide rails 22b and 22c, and a guide similar to the present embodiment are used. A table moving device 14b (see a solid line in FIG. 4) in which a ball screw 28 is arranged outside the rail 22c is selectively incorporated.

Using the machine tool 10a thus constructed, an experiment was conducted to compare the accuracy of repeated stop and the dynamic accuracy. This repeat stop accuracy refers to the positioning accuracy and yawing (yaw) deformation accuracy when the table 20 is reciprocally moved with a predetermined stroke (600 mm), and the dynamic accuracy is the accuracy when drilling a hole having a diameter of 100 mm. Depth accuracy is referred to (see FIG. 5). The results are shown in Table 1.

[0026]

[Table 1]

As a result, by providing the roller bearings 34a to 34c on the table 20, the table moving devices 14a and 14b were able to obtain almost the same values in terms of repeated stop accuracy and dynamic accuracy. Therefore, the table moving device 14 according to the present embodiment has an advantage that the table 20 can be smoothly and accurately moved in the arrow X direction even if the ball screw 28 is arranged outside the guide rails 22a to 22c. can get.

[0028]

According to the table moving device in the machine tool of the present invention, the following effects can be obtained.

Since the ball screw and the nut member are arranged outside two or more guide rails that support the table, the ball screw and the nut member can be taken out in a direction intersecting the axial direction of the ball screw. it can. As a result, even if a particularly long ball screw is used, another machine tool or the like can be arranged close to the axial direction thereof, and the work of replacing the ball screw and the nut member is simplified. .

Further, when a linear movement guide roller bearing that engages with two or more guide rails is used, even if the ball screw is arranged outside the two or more guide rails, the table can be smoothly and highly elevated. It can be moved with precision.

[Brief description of drawings]

FIG. 1 is a side view of a table moving device of a machine tool according to an embodiment of the present invention.

FIG. 2 is a plan view of the table moving device.

FIG. 3 is a front view of the table moving device.

FIG. 4 is a plan view of the experimental machine tool.

FIG. 5 is an explanatory diagram of depth accuracy tested by the experimental machine tool.

[Explanation of symbols]

 10 ... Machine tool 12 ... Base 14, 14a, 14b ... Table moving device 16 ... Tool 18 ... Processing unit 20 ... Table 22a-22c ... Guide rail 24 ... Support part 26 ... Nut member 28 ... Ball screw 30 ... Fixed bearing 32 ... Servo motors 34a to 34c ... Roller bearing 42 ... Z table 44 ... Column

Claims (2)

[Claims] 1. A two or more guide rails for supporting a table on which a machining unit including a tool is mounted and for guiding the table in a predetermined direction, and projecting outward of the two or more guide rails. A supporting portion provided on the table, a nut member attached to the supporting portion, and a nut member disposed outside the two or more guide rails along the two or more guide rails. A table moving device in a machine tool, comprising: a ball screw that is screwed to move the table along the two or more guide rails. 2. The table moving device according to claim 1, wherein the table includes a linear movement guide roller bearing that engages with the two or more guide rails.