JPH0767581B2 - Movable table moving mechanism of machine tool - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a movable table moving mechanism of a machine tool including a movable table for setting a workpiece and performing machining.

[Prior Art] Conventionally, for example, a machine tool having a movable table as shown in Fig. 5 is known. This machine tool is provided with two parallel rails 102 for guiding linear movement of a movable table 101, and each rail 102 is supported by these rails 102.
The movable table 101 is mounted on the movable bases 104 that slide on it and placed thereon to perform the linear motion of the movable table 101.

Then, a drive mechanism 10 including a ball screw or the like for controlling the positioning of the movable table 101 at a desired position.
3 was provided between the two parallel rails 102.

A machine tool provided with a movable table 101 that is movable in the X and Y directions is provided with a movable table 105 equivalent to this movable table 101 on the movable table 101 described above, and each movable table moves orthogonally. It is configured to be able to.

[Problems to be Solved by the Invention] However, in the conventional technology as described above, the straightness and squareness indicating the accuracy of the linear motion of the movable tables 101 and 105 are parallel to the straightness of the two parallel rails 102. Although it depends on the degree, it is a very difficult work to form these two rails 102 with straightness with high precision and to arrange the rails 102 in perfect parallel with each other. It is impossible to make them completely parallel to each other.

Therefore, since the distance between the two rails varies depending on the position, when the movable tables 101 and 105 move, the friction between the rail 102 and the moving table 104 that slides along the rail 102 greatly varies depending on the moving position. Then, this friction generates a couple of forces to rotate the movable table with the driving mechanism 103 such as a ball screw as a fulcrum, and the movable tables 101, 105
Since it rotates, the accuracy of the linear motion is greatly reduced. Further, since the frictional force between the rail 102 and the moving table 104 varies depending on the moving position of the movable tables 101 and 105, the output of the servo motor (not shown) for positioning and moving the movable tables 101 and 105 also fluctuates irregularly and the movable tables 101 and 105 move. Since the table cannot move stably, there is a drawback that the positioning accuracy is lowered.

Therefore, in order to solve the above-mentioned problems, the present invention provides a case where the movable table is rotated by providing an independent drive mechanism for positioning drive in the vicinity of each of the two parallel rails 102 which are separated from each other. The two rails are parallel to each other by preventing the generation of force from each other and by providing a connecting plate between one of the drive mechanisms and the movable table that can be finely moved in the direction perpendicular to the traveling direction of the movable table. It is an object of the present invention to provide a movable table moving machine of a machine tool that eliminates variations in sliding friction caused by the non-existence and enables highly accurate positioning.

[Means for Solving Problems] Next, means for solving the above problems will be described with reference to FIGS. 1 to 4 corresponding to the embodiment.

A movable table moving mechanism of a machine tool according to the present invention is provided with a drive mechanism for converting a rotary motion into a linear motion, the movable table performing a linear motion, and a rail that guides the linear motion by supporting the movable table. In the movable table moving mechanism of the machine tool according to the above; a first driving mechanism A, a first movable table 15 that linearly moves by the first driving mechanism A, and a guide for linear movement that supports the first movable table 15. The first combined with the first rail 12
A second driving mechanism B provided as a pair at a position apart from the first driving mechanism A, a second movable table 33 that linearly moves by the second driving mechanism B, and A second linear motion mechanism in which a second rail 30 that supports the second movable table 33 and guides linear motion is combined; and the first drive mechanism A and the second drive mechanism B are interlocked with each other. A connecting shaft 23; a movable table 41 which is erected on the first movable table 15 and the second movable table 33 and fixed to either one of the movable tables.
The movable table 41 is provided between the movable table 41 and the other movable base to which the movable table 41 is not fixed,
Connecting plate 73 that is flexible in the direction orthogonal to the movement direction of
By fixing one end of the connecting plate 73 to the one movable base and fixing the other end of the connecting plate 73 to the movable table 41, a direction orthogonal to the movement direction of the movable table 41. In addition, the movable table 41 is characterized by being capable of fine movement.

[Operation] As described above, the mechanism that linearly guides the movable table 41 of the machine tool is made into two independent mechanisms, and the first and second movable units are faithfully guided by the respective independent guide mechanisms to move straight.
Since the movable bases 15 and 33 are provided with the drive mechanisms A and B, respectively, the movable table 41 that is erected over the movable bases 15 and 33 and moves linearly is a movable table 41 that is generated by the movable table of the normal mechanism. It is possible to completely eliminate the movement that tries to turn (movement due to a couple).

Further, a structure is provided between one of the first and second movable bases and the movable table 41 so that the movable table 41 can move in a direction (lateral direction) orthogonal to the movement direction of the movable table 41 without rattling. By connecting the movable table 41 and the movable table 41 via one of the rails, even if the parallelism of the two guiding rails 12, 30 is poor, each rail 12, 30 can be moved when the movable table 41 moves linearly.
The sliding friction resistance generated between the movable table 15 and the movable table 15 and 33 becomes constant.

Further, since the other movable table is not provided with the above-described structure for lateral movement and the movable table and the movable table 41 are fixed to each other, the straightness of the movable table 41 in the movement direction is restricted. Only one rail guiding the movable table fixed to the movable table 41 is provided.

[Embodiment] FIG. 1 is a partially omitted perspective view of a movable table moving mechanism of a machine tool showing an embodiment of the present invention, and FIG. 2 is a partially omitted movable table movement mechanism of a machine tool showing the same embodiment. A side view, FIG. 3 is a sectional view taken along line III-III in FIG. 2 of the same embodiment, and FIG. 4 is a sectional view taken along line IV-IV in FIG.

The movable table moving mechanism of the machine tool of this embodiment is provided in a turret punch press machine by numerical control for punching the workpiece 50, and the workpiece 50 is held on the movable table 41 X and Y. It is to be moved in the direction (see FIG. 1).

First, in this machine tool, the first and second drive mechanisms A and B provided with the first and second ball screws 8 and 28 for moving the movable table in the Y-axis direction on the base frame 71 are parallel to each other. One pair is provided.

The first drive mechanism A, which is one of these drive mechanisms, is provided with a first servomotor 2 as a power source. A first motor gear 3 is fitted on the shaft of the servo motor 2 and meshes with a ball screw gear 4. The ball screw gear 4 is provided by being fitted to one end of the first ball screw 8. A bevel gear 5 is provided at one end of the first ball screw 8 in proximity to the ball screw gear 4. The bevel gear 5 is provided to drive a second drive mechanism B described later. In addition, a bracket having a built-in terminal bearing 10 at the other end of the first ball screw 8
11 is provided and fixed to the base frame 71. In addition, on both sides of the first ball screw 8, a first movable table is provided.
A first guide rail 12 and a first guide bar 14 for sliding linear movement and guiding linear movement are provided on a base frame 71 in parallel with each other.

The second drive mechanism B, which is the other drive mechanism, distributes the power of the first servomotor 2 by a connecting shaft 23 as a connecting body having a bevel gear 20 meshed with the above-described bevel gear 5 at one end. The bevel gear 26 provided at the other end of the connecting shaft 23 and the bevel gear 5 provided at one end of the second ball screw 28 mesh with each other to rotate the second ball screw 28. At the other end of the second ball screw 28, a bracket 11 having a built-in terminal bearing 10 is provided similarly to the first ball screw 8 and is fixed to the base frame 71. A second guide rail 30 and a second guide bar 32 for slidingly guiding the second movable base 33 are provided on both sides of the second ball screw 28 in parallel on the base frame 71. ing.

Then, the first ball screw 8 and the second ball screw 28
The first ball nut 9 and the second ball nut 29 are fitted in and respectively provided in parallel with each other. Then, these ball nuts 9 and 29 are adapted to convert rotational movement into linear movement. In other words, the first ball nut 9 and the second ball nut 29 are connected to the first ball nut 9 by the connecting shaft 23.
The power of the servo motor 2 is transmitted at the same time to make a linear movement in the Y direction.

Next, the movable bases 15 and 33 are the first and second drive mechanisms A and B described above.
The ball nuts 9 and 29 are built into each. The movable bases 15 and 33 are adapted to move linearly by the drive mechanisms A and B, respectively. First, a first guide slider 13 slidably fitted to the guide rail 12 is provided on the lower surface of the first movable table 15. Further, on the side surface of the first movable table 15, a rotatable cam follower 17 is formed on the first guide bar 14 to form a guide portion.
They are arranged in pairs so as to sandwich 14a. Then, the first guide rail 12 and the first guide bar 14
The first ball screw 8 guides the first movable table 15 when it moves linearly.

On the other hand, the second movable table 33 is also provided with the second guide slider 31 on the lower surface thereof and the cam followers 17 on the side surfaces thereof similarly to the first movable table. The second movable table 33 is guided by the second guide rail 30 and the second guide bar 32 when it is linearly moved by the second ball screw 28. Further, one end of a connecting plate 73 is fixed to the outer surface of the second movable table 33 by a plurality of screws 74.
The connecting plate 73 is formed in a plate shape by a flexible member.

Further, the movable table 41 is laid on the upper surfaces of the first movable table 15 and the second movable table 33 described above. The movable table 41 is provided with a second servo motor 42 which is a power source for the clamper rail body 45 that moves the workpiece in the X-axis direction. In addition, this movable table 41
A guide slider 47 is provided on the front side, and a cam follower 48 is provided as a pair on the back side of an upper plate 41a formed on the upper part of the movable table 41. Further, the first movable table 15 side of the movable table 41 is fixed to the first movable table 15 with a fixing screw 69. On the outer surface of the movable table 41 on the side of the second movable table 33, the connecting plate described above is attached.
The other end of 73 is fixed by a plurality of screws 74. That is, the second movable table 33 and the movable table 41 are connected by the connecting plate 73. Since the connecting plate 73 is a flexible member, the movable table 41 is adapted to slightly move in a direction orthogonal to the movement direction of the second movable table 33.

A clearance is provided between the movable table 41 and the second movable table 33, and the connecting plate 73 described above is used as the second movable table.
The movable table 41 and the second movable base 33 do not come into contact with each other when the movable table 41 moves in a direction orthogonal to the moving direction of the 33.

Further, the clamper rail body 45 is provided with a plurality of work clampers 49 for chucking a workpiece 50 such as a metal plate. The work clamper 49 chucks the workpiece 50 by air pressure or hydraulic pressure. This clamper rail body has a rack gear 44 and a guide rail 46 on the back side.
Is provided, the second motor gear 43 provided in the second servomotor 42 and the rack gear 44 mesh with each other, and the guide slider 47 and the guide rail of the movable table 41 are provided.
46 is slidably fitted. And
Clamper rail body using the second servo motor 42 as a power source
45 is movable in the X-axis direction. The upper end of the clamper rail body 45 is held by a cam follower 48 provided on the movable table 41 to guide the linear movement in the X-axis direction.

Further, in this machine tool, in order to support the workpiece 50 chucked by the work clamper 49 so as not to bend, a support table 35 is provided between the drive mechanisms A and B on the base frame. ing. And this support table
A plurality of rotary supports 36 are provided on the support 35 so that the workpiece 50 can be smoothly moved on the support table 35.

Therefore, in the movable table moving mechanism of the machine tool configured as described above, when the first servomotor 2 for the Y axis rotates, the first motor gear 3 rotates, and the ball screw gear meshed with the gear 3 is rotated. Rotate 4. This rotation causes the first ball screw 8 to rotate and the first ball screw 8 to rotate.
The bevel gear 5 fitted to the ball screw 8 is also rotated. The rotation of the bevel gear 5 of the first drive mechanism A rotates the bevel gear 20 meshed therewith and fixed to one end of the connecting shaft 23, and further rotates the bevel gear 26 fixed to the other end of the connecting shaft 23. Let The rotation of the bevel gear 5 is fitted to the second ball screw 28,
The bevel gear 5 of the second drive mechanism B meshing with the bevel gear 26 is rotated, and the second ball screw 28 is rotated. As a result, the ball screws 8 and 28 rotate simultaneously, and the first ball nut 9 and the second ball nut 29 fitted to the respective ball screws are moved to the same distance in the linear direction. Due to this movement, the first movable table 15 and the second movable table 33 move in the same direction and the same distance.

Then, the first movable table 15 and the movable table 41 are fixed by the fixing screws 69.
Fixed by the second movable table 33 and movable table
Since 41 is connected by a connecting plate 73 that guides the second movable table 33 in a direction orthogonal to the movement direction of the second movable table 33, the movable table 41 can move accurately and smoothly in the Y direction.

[Advantages of the Invention] As described above, the movable table moving mechanism of the machine tool according to the present invention does not deteriorate the drive positioning accuracy even if the parallelism of the two rails for linearly guiding the movable table is low, and the machining is performed. Since no special consideration is required above, a highly accurate positioning mechanism can be easily obtained even if the processing is performed by a general processing machine and the assembly and adjustment technique is used.

Furthermore, in this assembly and adjustment work, it is not necessary to consider the mutual relationship between the two rails, and the work is independent for each side, and the work for producing the straightness of the movement of the movable table is only one for one side. Since it is a rail, it is easy to obtain a movable table with good straightness.

In addition, since the movement of the movable table (rotational motion due to a couple) and vibration during the start / stop of positioning are hindered by the two-system drive mechanism method, there is no change in the sliding resistance, so high-speed positioning The operation can be performed accurately.

As described above, the high-speed operation and high-precision positioning of the machine tool can be performed at the same time, and the assembly and adjustment work can be easily performed, so that the production cost is lower than that of the conventional one-system drive system.

[Brief description of drawings]

FIG. 1 is a partially omitted perspective view of a movable table moving mechanism of a machine tool showing an embodiment of the present invention, and FIG. 2 is a partially omitted side view of a movable table moving mechanism of a machine tool showing the same embodiment. 3 is a sectional view taken along line III-III in FIG. 2 of the same embodiment, and FIG. 4 is a sectional view taken along line IV-IV in FIG.
FIG. 1 is a perspective view showing a conventional machine tool. A: first drive mechanism, B: second drive mechanism, 2 ...
Second servo motor, 3 ... First motor gear, 4 ...
Ball screw gear, 5 ... bevel gear, 8 ... first ball screw, 9 ... first ball nut, 10 ... end bearing,
11 ... Bracket, 12 ... First rail (first guide rail), 13 ... First guide slider, 14 ... First guide bar, 14a ... Guide part, 15 ... First Mobile platform, 17
...... Cam follower, 20 ...... Bevel gear, 23 ...... Coupling (coupling shaft), 26 ...... Bevel gear, 28 ...... Second ball screw, 29 ...... Second ball nut, 30 ...... Second rail (No. 2 guide rails), 31 ... second guide slider, 32 ... second guide bar, 33 ... second movable base, 35
…… Support table, 36 …… Rotary support, 41 …… Movable table, 41a …… Upper plate, 42 …… Second servo motor, 43 ……
Second motor gear, 44 ... Rack gear, 45 ... Clamper rail body, 46 ... Guide rail, 47 ... Guide slider, 48 ... Cam follower, 49 ... Work clamper, 50 ...
… Working material, 69 …… Fixing screw, 71 …… Base frame,
73 …… Connecting plate, 74 …… Screw.

Claims (1)

[Claims] 1. A movable table movement of a machine tool by numerical control, which comprises a movable table for linear movement by incorporating a drive mechanism for converting rotational movement into linear movement, and a rail for supporting the movable table and guiding linear movement. In the mechanism, a first drive mechanism (A), a first movable base (15) that linearly moves by the first drive mechanism (A), and a guide for linear motion that supports the first movable base (15) First rail (12)
A first linear movement mechanism that is a combination of a second driving mechanism (B) and a second driving mechanism (B) that are provided in a pair at a position apart from the first driving mechanism (A). A second movable table (33) which moves linearly and a second rail (30) which supports the second movable table (33) and guides the linear movement.
A second linear motion mechanism that is a combination of the above; and the first drive mechanism (A) and the second drive mechanism (B).
A movable shaft (41) which is erected on the first movable table (15) and the second movable table (33) and is fixed to either one of the movable table (15) and the second movable table (33). A connection provided between the movable table (41) and the other movable base to which the movable table (41) is not fixed, and is flexible in a direction orthogonal to the moving direction of the movable table (41). A plate (73); and one end of the connecting plate (73) is fixed to the one movable table,
By fixing the other end of the connecting plate (73) to the movable table (41), the movable table (41) can be finely moved in a direction orthogonal to the movement direction of the movable table (41). Movable table moving mechanism for machine tools.