JPS61293741A - Table transferring device - Google Patents

Abstract

PURPOSE:To provide a long distance motion by interposing a plurality of linear motors between two movable tables and thereby moving one of the tables while the other is in the condition fixed to a bed through the action of a brake. CONSTITUTION:A stationary bed 1 is equipped at both sides flanges protruding upward and extending parallelly in the longitudinal direction, and a track table 3 is fixed to the bed 1 with a fixture alongside the inner side faces of the two flanges. No.1 and 2 movable tables 5, 6 are installed on said track table 3 through a linear bearing in such a way as borne movable freely along the track table 3. Two pairs of linear motors 7, 8 are interposed between the mating faces of No.1 and 2 movable tables 5, 6. A stator 7b and a moving element 8a are arranged on the No.1 table side 5 while a moving element 7a and a stator 8b are arranged on the No.2 table side 6.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a table transfer device used in, for example, machine tools.

(Prior Art) In a conventional table transfer device, a movable table is slidably attached to a fixed bed, and the feeding mechanism of this movable table is composed of a ball screw and a rotating motor such as a servo motor or a stepping motor that rotates the ball screw. It was common practice to control the linear motion of a movable table using the rotational motion of a ball screw for highly accurate positioning. However, due to bank lash of the ball screw, the responsiveness during starting and stopping is poor, making it impossible to achieve high positioning accuracy.Also, if the pitch of the ball screw is reduced to achieve high accuracy, the high speed will be poor, and the relationship between the ball screw and the rotation There were drawbacks such as the need to assemble the motor, which increased the size of the device.

On the other hand, using a linear motor does not require a mechanical drive transmission mechanism such as a ball screw, so it has good responsiveness and can be driven at high speed. Various table transfer devices using linear motors have been proposed, which have advantages such as being able to be incorporated between a table transfer device and a fixed bed and being miniaturized.

(Problem to be Solved by the Invention) However, in the case of such a conventional example, the stator is usually fixed to the fixed bed side and the movable table moves on it, so the movable range of the movable table is It was limited to the length of the stator. Therefore, when moving a long distance, it was necessary to manufacture a long stator. On the other hand, the stator teeth of the stator are formed by etching a steel plate or the like, but as the stator becomes longer, a longer bus for etching is required, which increases production equipment and increases costs. Furthermore, there is a problem in that the manufacturing cost of the stator itself increases in proportion to its length. In order to solve this problem, it is possible to form a long stator by joining together several short stators, but the joint part of each stator must be formed with the same accuracy as the pinch of the stator teeth. It is difficult to add joints, and for example, even when traveling at a pitch of 1 m, there is a problem that the pitch exceeds or is less than 1.5 wbm at the joint portion, resulting in poor running accuracy of the movable table. Furthermore, there is a problem in that the feed pitch still varies depending on the accuracy of the stator teeth.

The present invention was made to solve the above problems, and its purpose is to
To provide a table transfer device which is infinitely movable even over a long distance longer than the length of a stator and can be precisely fed.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a first movable table and a second movable table spaced apart from each other in the vertical direction on a fixed bed. A first movable table and a second movable table are respectively attached via linear bearings so as to be movable in the same direction, and the first movable table and the second movable table are attached to the fixed bed. A brake means is attached between the first movable table and the second movable table to select one of the first movable table and the second movable table to the fixed bed by the brake means. It consists of a plurality of interposed linear motors that move one motor while the other is fixed.

(Example) In the following, the present invention will be explained based on the illustrated embodiment. In Figs. 1 to 6 showing a linear motor according to a first embodiment of the present invention, 1 is a fixed bed, and Flanges 2.2 are formed at the ends to project upward and extend parallel to each other in the longitudinal direction, and a track 3.3 is installed in parallel along the inner surface of both flanges 2.2 to attach fasteners such as bolts. 4, it is stuck to the fixed bed l and is worn out. The first movable table 5 and the second movable table 5 are connected to the track 3.3 via near bearings.
A movable table 6 is movably supported along a track 3.3. First movable table 5 and second movable table 6
Two sets of linear motors 7.8 (near pulse motors in this embodiment) are interposed between the opposing surfaces of the motors. The arrangement of the stator 7b and the movable element 7a of one of the first linear motors 7 and 8 is such that the stator 7b is on the pull 5 side and the movable element is on the second movable table 6 side. 7a is arranged, and the arrangement of the stator 8b and mover 8a of the other second linear motor 8 is opposite to that of the first linear motor 7, and the mover 8a is on the first movable table 5 side, A stator 8b is arranged on the second movable table 6 side. The first and second movable tables 5.6 each have four pairs of linear base flanges 9.6. ... ;lO...
It is supported on the tracks 3, 3 by. That is, taking the second movable table 6 as an example, two pairs of linear bearings 9. ... is a fastener 11 such as a bolt
..., and two pairs of linear bearings 9. are attached to both sides of the stator 8b of the second linear motor 8. ... are fixed by fixing tools 11.... Further, between the linear bearings 9.9, electromagnetic brakes 12.12 as a pair of braking means are fixed, and a second
A pair of electromagnetic brakes 12.12 are also fixed to both sides of the central portion of the stator 8b of the linear motor 8 between the linear bearings 9.9.

The first movable table 5 also has the same configuration as the second movable table 6, and has four pairs of linear bearings of 10° and 2
Pair of electromagnetic brakes 12. ... is installed.

On the other hand, each linear bearing 9. attached to the first movable table 5 and the second movable table 6 is mounted on the track base 3.3. Ball rolling grooves 3a... in which lO is guided are formed at two locations, upper and lower, and the first movable table 5 runs linear bearings 10... along the lower ball rolling grooves 3a... At the same time, the second movable table 6 moves along the upper ball rolling i$13a through the linear bearings 9. Each first and second movable table 5.6 has an electromagnetic brake 12. It is fixed to the fixed bed 1 by..., but this electromagnetic brake 12
．． . . is the track base 3 when braking as shown in Fig. 7.
A brake shoe 13 that is pressed against the brake shoe 13, a plunger 14 that moves the brake shoe 13 back and forth in a direction perpendicular to the track base 3, and an electromagnetic coil 1 that operates the plunger 14.
5, when the plunger 14 is energized, the plunger 14 is attracted and the brake shoe 13 is separated from the track 3, and when the power is not energized, the brake shoe 13 is pressed against the track 3 by the spring 16.

Each linear bearing9. As shown in FIGS. 8 to 10, 1O has a bearing block 19 which is provided with two ball rolling grooves 17°17 on one side and a ball escape hole 18°18 inside, and The ball retainer 2o holds a row of loaded balls, and a pair of side covers 21.21 communicate the ball rolling grooves 17, 17 with the ball relief holes 18.18. Is the load ball 22.22... the ball rolling groove 17.1? and ball escape holes 18.18. This ball rolling groove 17°1
The contact angle α between 7 and the load ball 22.22... is approximately 45
degree, but it is not limited to 45 degrees, but 3 degrees.
It may be within the range of 0 to 60 degrees. Also, each linear bearing9. ..., 10. . . . and the track base 3°3, for example, with a clearance adjustment bolt 23 as shown in FIG.・
Adjusted by... In other words, the clearance adjustment bolt 23
9. Linear bearing by tightening. ...,
10. . The reaction force of the pressing force of... acts on the linear bearing 9 on the opposite side, and preload is applied to the load balls 22.... As a method for applying preload, an eccentric pin, a taper gib, etc. may also be used.

Next, FIG. 11 shows the main parts of the first linear motor used in this embodiment, in which the mover 7a has, for example, a permanent magnet 24 interposed in the center, and two magnetic cores 25. 26 are arranged opposite to each other, one magnetic core 25 has a first magnetic pole 27 and a second negative magnetic pole 28 magnetized to the north pole by the permanent magnet 24, and the other magnetic core 26 has The permanent magnet 24 forms a third magnetic pole 29 and a fourth magnetic pole 30 that are magnetized to the S pole.

As shown in FIG. 11, the stator 7b has fixed teeth 7b' having a U-shaped cross section extending in a direction substantially perpendicular to the longitudinal direction, and are provided at equal intervals at the same pitch P over substantially the entire length in the longitudinal direction. There is. Magnetic pole teeth 27a to 30a having the same pitch as the stator 7b are also formed at each of the magnetic poles 27 to 3 degrees, respectively.

The first magnetic pole 27 and the second magnetic Pi 28 on the N pole side include
A first coil 31 and a second coil 32 are wound and connected in series so that magnetic fluxes in opposite directions are generated when current flows, and are connected to a pulse generation source (not shown). electrically connected. On the other hand, a third magnetic pole 29 and a fourth magnetic pole 30 on the S pole side are also wound with a third coil 33 and a fourth coil 34, which are similarly connected in series. )It is connected to the. Here, for convenience of explanation, for example, the magnetic pole tooth 2 of the first magnetic pole 27
The phase of the magnetic pole tooth 28a of the second magnetic pole 28 with respect to 7a is
It is assumed that the magnetic pole teeth 30a of the fourth magnetic pole 30 are also shifted in phase by a pinch (VlP) with respect to the magnetic pole teeth 29a of the third magnetic pole 29. The third magnetic pole tooth 8i27 on the north pole side and the magnetic pole teeth 27a, 28a of the second magnetic pole 28 on the south pole side
magnetic pole teeth 29a, 30 of the magnetic pole 29 and the fourth magnetic pole 30
It is assumed that a is out of phase by 2 pitches (AP).

Here, the operating principle of the linear pulse motor of this embodiment will be explained. 12 fal to ldl are schematic diagrams showing the operating principle of the linear pulse motor, in which the first coil 31 and the second coil 32 are connected to the terminal a, the third coil 33 and the fourth coil A pulse is input to the terminal 34 from the terminal. In Fig. 12(a), terminal a is turned in the direction of exciting the first magnetic pole 27゛ (mode ■).
, FIG. 12 (in BL, the terminal A is in the direction of exciting the fourth magnetic pole 30 (mode ■), in FIG. 12 (C), the terminal a is in the direction of exciting the second magnetic pole 28 (mode ■), Figure 12 (In dl, the terminal is in the direction of exciting the third magnetic pole 29 (
mode (■), each shows a state in which a pulse is input.

Here, Table 1 shows the magnetic force generation state of each magnetic pole in the case of modes ① to ②.

As shown in Table 1, the magnetic force of the first magnetic pole 27 on the N pole side is strong, and the magnetic force of the first magnetic pole 27 and the stator 7b is strong.
The movable element 7a is held in a stable state by the suction force between it and the fixed teeth 7b'. On the other hand, the third and fourth magnetic poles 29 and 30 on the S pole side are connected to the stator 7b and the fixed tooth 7b', respectively.
The phase is shifted by 2 pitches. In mode (2), the magnetic force of the coil 31 of the first magnetic pole 27 disappears, and instead the magnetic force of the fourth magnetic pole 30 on the S pole side becomes strong, and the movable element 7a Fixed tooth 7 b
A pitch (
It will advance by W p). At this time, the first and second magnetic poles 27 and 28 on the N pole side are out of phase by 2 pitches (!4 P).

Furthermore, in mode (2), the magnetic force of the second magnetic pole 28 on the N pole side becomes stronger, and the second magnetic pole 28
The movable element 7a moves relatively in the direction in which the phase matches '' and advances by x pitch (AP), and the third and fourth magnetic poles 29.30 on the S pole side are out of phase by Z pitch (!4P). .

In mode (2), the magnetic force of the third magnetic pole 29 on the S pole side becomes strong, and the mover 7a moves relatively in the direction where the third magnetic pole 29 matches the fixed tooth 7b' of the stator 7b in phase. 〃Go forward by a pitch (!4 p). Return to mode ■ again and N
The magnetic force of the first magnetic pole 27 on the pole side becomes strong, and the movable element 6
moves relatively by A pitch (%P) and reaches the state shown in Figure 12 (al).In this way, by repeating mode ■ to ■, it moves by A pinch (!4 P) per pulse. .

In the above explanation, one-phase excitation was explained, but it may be driven by two-phase excitation in which two-phase current is constantly passed, or a 1-2-phase excitation method in which current is passed alternately in one phase and two phases may be used. .

The linear motor having such a configuration is driven as follows. First, the electromagnetic brake 12 of the first movable table 5. ... is turned off, the first movable table 5 is fixed to the track base 3.3, and the electromagnetic brake 12.3 of the second movable table 6 is turned off. . . is turned on to make the second movable table 6 free with respect to the track base 3.3, and the first movable table 6 is turned on. A pulse is input to each movable element 7a, 8a of the second linear motor 7°8, and the second movable table 6 is driven forward by a predetermined amount (leftward in the figure) as shown in FIG. 13 (al, fbl, (C1)).
In this case, the mover 7a of the first linear motor 7
moves forward relative to the stator 7b, but the second linear motor 8
In order to move the stator 8b, the movable element 8a is attached to the first movable table 5 fixed to the track base 3.
In the direction of retreating relative to the stator 8b (to the right in the figure),
A pulse is input to , and the stator 8b is moved as a reaction. Next, after the second movable table 6 advances a predetermined amount and stops, the electromagnetic brake 12 of the second movable table 6 is turned off, the second movable table 6 is fixed to the track base 3.3, and the first movable table 6 is fixed to the track base 3.3. Electromagnetic brake of table 5 12.・
. . is turned on to make the first movable table 5 free with respect to the tracks 3, 3. 1st. Second linear motor7.
A pulse is input to each of the movable elements 7a and 8a in the direction in which the second movable table 6 moves backward (to the right in the figure) with respect to the first movable table 5. Then, the first movable table 5
Figure 3 (Forward as shown in C1 to let (left direction in the figure)
and stop at the specified position.

Furthermore, the first movable table 5 is moved again in the state shown in FIG.
The electromagnetic brake 12 of the second movable table 6 is turned off and the first movable table 5 is fixed relative to the tracks 3, 3, and the electromagnetic brake 12 of the second movable table 6 is turned off. . . is turned on, the second movable table 6 is made free, and the above-described operation is repeated, so that the second movable table 6 and the first movable table 5 alternately move forward (
(to the left in the figure), and moves infinitely along the tracks 3, 3.

Since the linear motors are configured in two series in this way, the propulsive force of each movable table 5.6 is doubled. Also each 1st. If there is variation in the feed amount per pulse by the second linear motor 7.8, for example if one linear motor advances too much than the predetermined feed amount and the other feed amount lags behind, the feed amount will change. Errors cancel out. In addition, if both of the tables 5 and 6 advance too far beyond the predetermined feed amount, the error in the feed amount of each table 5, 6 can be suppressed to an intermediate value between the errors of both linear motors 7.8, and the first linear motor 7 and the second linear motor 8 mutually correct each other, and the feeding accuracy of each table 5, 6 is improved.

Furthermore, since the stators 7b, 8b and movers 7a, 8a of the first linear motor 7 and second linear motor 8 are arranged in reverse, the first movable table 5 and the second movable table 6 have the same shape. , with one movable table. It can also be used as the second movable table 5.6, increasing versatility.

Also linear bearing 9. ..., 10. Each first . Since the second movable table 5.6 is moved,
Sliding resistance is small, and even when a large load is applied, the increase in frictional resistance is small and the product slides smoothly. Moreover, the linear bearing 9 of this embodiment. ....

By using lOl..., a linear bearing 9. ..., 10. 1 compared to not using ...
It becomes possible to support 0 to 100 times the load. Furthermore, linear bearing9. ..., 10. The contact angle between the loaded balls 22 and the ball rolling surfaces 17 was approximately 45 degrees. The load applied to the second movable table 5°6 in four directions, up, down, left and right, can be supported equally. Furthermore, since high rigidity is achieved by applying a preload, the gap between the first movable table 5 and the second movable table 6 is maintained constant, stable running performance is obtained, and pitching meandering where the pitch varies during running is avoided. Problems such as yawing and rolling, which involves moving while turning from side to side, are prevented.

Next, a second embodiment of the present invention is shown in FIGS. 14 to 19, and the same components as in the first embodiment will be described with the same reference numerals. Well,
Similar to the first embodiment, the linear motor 7.8 has a double configuration, but the track 3.3 has two ball rolling grooves 17.
A linear bearing 10 is only provided and is fixed to the first movable table 5. ...and the second movable table 6
Linear bearing fixed to 9. ... move along the same ball rolling groove 17.

With this configuration, unlike the first embodiment, the table cannot be shared, but the device can be made thinner by the thickness of the linear bearing. The other configurations and functions are the same as those in the first embodiment, so their explanations will be omitted.

In the second embodiment of Wooden Tablet-1, the arrangement of the stator and mover of each linear motor is reversed, but two stators are placed on the first movable table side and two stators are placed on the second movable table side. A configuration in which two movers are provided, or the opposite configuration may be used. Further, although an example of two linear motors is shown, three or more linear motors may be installed. Further, although a linear pulse motor driven by a pulse signal is used as the linear motor, a linear induction motor, a linear DC motor, etc. may also be used.

(Effects of the Invention) The present invention has the above-described configuration and operation, and the first movable table and the second movable table are each provided with a brake means, and one of the first movable table and the second movable table is selectively operated. Since the stator is fixed to a fixed bed and the first movable table and the second movable table are moved alternately, it is possible to move an infinitely long distance regardless of the length of the stator. Therefore, even when transporting long distances,
There is no need to manufacture a long stator as in the past, making it easier to manufacture the device and reducing costs. Furthermore, precise feeding is possible without deterioration in feeding accuracy due to variations in joints that occur when stators are connected as in the past.

In addition, since linear bearings are used, there is no variation in pitch (pitching), meandering (yawing), or sideways shaking (rolling) when moving, resulting in stable and smooth running performance. Furthermore, by arranging multiple linear motors, several times the propulsive force can be obtained, and even if the feed amount of each linear motor varies, the error in the feed amount is reduced by mutually correcting, and the feed accuracy is increased. Various effects can be obtained, such as the ability to

[Brief explanation of drawings]

1 is a plan view of a table transfer device according to a first embodiment of the present invention, FIG. 2 is a longitudinal sectional view of the device shown in FIG. 1, and FIG. 3 is a sectional view taken along the line 4 is a sectional view taken along the line rV-IV of FIG. 1, FIG. 5 is a sectional view taken along the line V-V of FIG. 1, FIG. 6 is a sectional view taken along the line Vl-Vl of the present invention, and FIG. FIG. 8 is a front view of the linear bearing of the device in FIG. 1, FIG. 9 is a plan view of the device in FIG. 8, and FIG. 1O is the X in FIG. 9. -X, *Cross-sectional view, Figure 11 is an enlarged cross-sectional view of the main parts of the mover and stator, Figure 12 +al
18) to +dl are schematic front views of linear pulse motors showing the operating principle of linear pulse smoke;
1 is a schematic front sectional view showing the operating state of the device shown in FIG. 1, FIG. 14 is a plan view of a table transfer device according to a second embodiment of the present invention, and FIG. 15 is a longitudinal sectional view of the device shown in FIG. 14. Figure, 1st
6 is a sectional view taken along the line xvr-xvr in FIG. 14, FIG. 17 is a sectional view taken along the line X■-X■ in FIG. 14, FIG. 18 is a sectional view taken along the line The figure is a sectional view taken along the line XIX-XIX. Explanation of symbols 1... Fixed bed 5... First movable table 6... Second movable table 7... First linear motor 8... Second linear motor 9. 10... Linear Bearing 12... Electromagnetic brake (braking means) Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 10 Q ″0 Fig. 13 <a> (e) Fig. 16 Procedural amendment stamped) September 18, 1986 Japan Patent Office Commissioner Kuro 1) Mr. Yu Akira 2, Invention title table transfer device 3, Relationship with the amendment person case Patent applicant address 2-34-8-4 Higashi Tamagawa, Setagaya-ku, Tokyo;
Agent 〒105 □ Address Shinbashi OWK, Shintachibana'3-s-2, Rental Ward, Tokyo
5th floor of the building (1) Drawings (Figures 4, 5, and 7) 6. Details of correction (1) The drawings (Figures 4, 5, and 7) will be corrected as shown in the attached sheet. Above Figure 5 Figure 7

Claims (2)

[Claims] (1) A first movable table and a second movable table are provided vertically apart from each other on a fixed bed, and the first movable table and the second movable table are respectively attached to be movable in the same direction via linear bearings, A brake means is attached to the first movable table and the second movable table for fixing the first movable table and the second movable table to the fixed bed, and a brake means is attached to the first movable table and the second movable table. The table transfer method is characterized in that a plurality of linear motors are interposed to move one of the first movable table and the second movable table while the other is selectively fixed to the fixed bed using a brake means. Device. (2) There are two movable tables arranged between the first movable table and the second movable table in the moving direction of the first and second movable tables.
A patent characterized in that a linear motor is interposed, one movable element of the linear motor is disposed on the first movable table side, and a movable element of the other linear motor is disposed on the second movable table side. A table transfer device according to claim 1.