JPH01301033A - Xy table with linear motor - Google Patents

Abstract

PURPOSE:To improve responsibility and a positioning accuracy by fitting an intermediate saddle in an X axial direction to a base and a table main body in a Y axial direction to the intermediate saddle freely slidably via a linear bearing respectively and driving by a linear motor. CONSTITUTION:An intermediate saddle 2 is fitted to a base 1 in an X axial direction and a table main body 3 to the intermediate saddle 2 in a Y axial direction freely slidably via a linear bearing 5 respectively. Plural stators 9 of linear motors are arranged in parallel so that the phase of the respective fixed tooth may be slided on either one part of the upper face of the base 1 or the lower face of the intermediate saddle 2 and either one part of the upper face of the intermediate saddle 2 or the lower face of the table main body 3 and also plural needles 8 of the linear motors corresponding to the stator 9 are provided in parallel at the respective other parts. The responsibility of the actuation/stopping time is improved by lightening an XY table, a fine adjustment and quick feeding are enabled and positioning accuracy can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an XY child table using a linear motor as a drive section.

(Prior Art) In a conventional XY child table, the table main body attached to the base via an intermediate saddle has an X axis that is orthogonal to each other,
It is configured to be able to slide freely in the Y-axis direction, and its feeding mechanism uses a Gale screw and a ceramic screw. It was constructed by combining a rotating motor such as a motor or a stepping motor (Japanese Patent Application Laid-Open No. 58-214015).

That is, a rotatable screw shaft is disposed in the upper part of the base in the X-axis direction, a nut that is screwed onto this screw shaft is fixed to an intermediate saddle, and a rotary motor is connected to the end of the screw shaft. Due to the rotation of A nut to be screwed onto the screw shaft is placed at the bottom of the table body, and the table body is moved in the Y-axis direction relative to the intermediate saddle by the rotation of a rotary motor connected to the end of the screw shaft. It had become.

Also? There is also known a transfer device in which the nut rotates relatively with the rotation of the 1M-hole screw, thereby making it possible to finely move and rapidly move the shifter body based on the sum and difference of the rotations of the 1M-hole screw and the nut.

(Problems to be Solved by the Invention) By the way, in the structure of the conventional example described above, by controlling the rotation of the rotary motor, the Y-axis, Y-axis, and
Although the axial movement is controlled, the inertia of the moving parts is large due to the installation of rotating motors, ball screws, etc.
There has been a problem in that the responsiveness at the time of starting and stopping is poor, resulting in poor positioning accuracy.

In addition, since a ball screw is used, the rotational torque causes twisting of the screw shaft, and backlash occurs between the screw shaft and the NAND, resulting in poor responsiveness.

As expected, there were problems in that the positioning accuracy could not be made high, space was required to install the rotary motor and ball screw, and the overall size of the XY table became large.

In addition, for models capable of fine movement and rapid traverse, a motor for rotating the nut is required in addition to the motor for rotating the ball screw, and it is necessary to install two motors each in the Y-axis and Y4111 directions. There were problems in that the weight increased and the inertia force became large, the positioning accuracy deteriorated, and the overall size of the xY table further increased.

Therefore, the present invention aims to reduce the weight of moving parts such as the table body, increase the responsiveness during starting and stopping, improve the positioning accuracy of the table body, achieve -59+z, @quantization, and reduce fine movement. Another object of the present invention is to provide an XY table that allows fast forwarding.

(Means for solving the problem) In order to achieve the above purpose, the intermediate saddle is attached to the base via a linear bearing on the X axis. At the same time, the table body is attached to the intermediate saddle via a linear bearing so as to be slidable in the Y-axis direction perpendicular to the Y-axis, and between the intermediate saddle and the base and between the intermediate saddle and A linear motor consisting of a stator and a movable element is interposed between the table body and the table body. A plurality of stators are arranged in parallel on either the upper surface of the base or the lower surface of the intermediate saddle so that the fixed teeth of each stator are out of phase, and on the other side, a plurality of movers corresponding to the stators are arranged in parallel. has been done.

Further, on either the upper surface of the intermediate saddle or the lower surface of the table body, a plurality of stators are arranged in parallel so that the fixed teeth of each stator are out of phase, and on the other side, a plurality of movers corresponding to the stators are arranged in parallel. (Embodiments) The present invention will be described below based on the illustrated embodiments. 11. In FIGS. 1 to 6 showing an XY table with a linear motor according to an embodiment of the present invention. ] is the base, 3
is a table body attached to a base 1 via an intermediate saddle 2.

If the elongated direction of the base 1 is the Y-axis, and the direction parallel to the top surface of the base and orthogonal to the Y-axis is the Y-axis, then the top surface of the base has tracks 4, 4 extending in the X-axis direction. These tracks 4, 4 are held in parallel by four linear bearings 5, 5, 5, 5 attached to the lower surface of the intermediate saddle 2, and the intermediate saddle 2 is connected to the track base. It is slidable in the axial direction of 4 and 4. Furthermore, four linear bearings 5, 5, 5.5 are attached to the upper surface of the intermediate saddle 2, and the track base is arranged on the lower surface of the table body 3 in the Y-axis direction by these linear bearings 5, 5, 5.5. 6.6 is held,
The table main body 3 is slidable in the Yl11h direction with respect to the base.

Linear bearing 5. ...as shown in Figure 3.

Two ball rolling grooves 5a, 5a are provided on one side, and one groove is provided inside. - a bearing block 5C provided with ball relief holes 5b, 5b, a retainer 5d for holding two rows of load balls, ball rolling grooves 5a, 5a and a ball relief hole 5b;
A side lid 5e communicating with the side lid 5b.

Load balls 5f, . . . are ball rolling grooves 5a, 5a and ball relief holes 5b.

5b. This ball roll a
Although the contact angle α between the load ball 5f and the load ball 5f is approximately 45 degrees, it is not limited to 45 degrees and may be in the range of 30 to 60 degrees.

Also, between the base 1 and the intermediate saddle 2, and between the intermediate saddle 2
and the linear bearing 5.5, 5 between the table body 3
．． The gaps between 5 and the tracks 4, 4 and 6, 6 are adjusted by gap adjusting bolts 7, . In other words, gap adjustment? Ruto 7. By tightening..., the linear bearings 5, 5 are pressed toward the track 4 side, and the gap is adjusted. The reaction force of the pressing force of the bolt 7°7 is the intermediate saddle 2
It acts on the linear bearing 5.5 on the opposite side via , presses against the track 4 side, and applies preload to the load balls 5f, . . . .

On the other hand, linear motors are interposed between the intermediate saddle 2 and the base and between the intermediate saddle 2 and the table main body 3, respectively. In this embodiment, the linear motor is a linear motor and is composed of a combination of a movable element 8 and a stator 9. Pulses are input to the movable element 8 from a pulse generation source (not shown). On the base, there are two rows of flat plate-shaped first stators 9a and second stators parallel to the track 4.4. The lower surface of the intermediate saddle 2 faces the first stator 9a and the second stator 9b, and the movable elements 8.8, 8. 8
is installed. Each movable element 8 is composed of a permanent magnet 8a interposed in the center and two magnetic cores facing each other on the left and right sides of the permanent magnet 8a. First magnetic pole 8b and second magnetic pole 8
C is formed, and the other m score includes a third magnetic pole 8d and a fourth magnetic pole 8e which are borated to the S pole by the permanent grinding stone 8a.
is formed.

The first stator 9a and the second stator 9b have fixed teeth having a U-shaped cross section extending across the X-axis as shown in the sixth section. are placed at equal intervals. Each magnetic pole 8b, &c
, +3d, and +3e are also formed with magnetic pole teeth having the same pitch as the first stator 9a and the second stator 9b.

A coil lla and a second coil 11b are wound around the first S pole 8b and the second magnetic pole 8C on the N pole side, and when a current flows, they rotate in opposite directions. The pulse generators are connected in series so as to be electrically connected to a pulse generation source (not shown). On the other hand, a third coil 11C and a fourth coil 11. which are connected in series are also connected to the third magnetic pole 8d and the fourth magnetic pole 8e on the S pole side. d is wound and connected to a pulse generation source.

Here, for example, the second m pole 8 is
In C, the phase of the magnetic pole teeth is shifted by ]/2 pitches, and the phase of the magnetic pole teeth of the fourth magnetic pole 8e is similarly shifted by ]/2 pitches from the third magnetic pole 8d. . Further, with respect to the magnetic pole teeth of the magnetic pole 8b and the second magnetic pole 8C on the N pole side, the third magnetic pole 8d and the 40th sharpened pole 8 on the S pole side
The magnetic pole teeth of e are out of phase by 17'4 pitches, and furthermore, the first stator 9a and the second stator 9b described above are out of phase.
will be explained below under the condition that the phases are shifted by ]/8 pinches, respectively.

First, the operating principle of the linear pulse motor of this embodiment will be explained. FIGS. 7(a) to 7(a) are schematic diagrams showing the operating principle of a linear pulse motor, in which the first coil IIIL and the second coil]1. Pulses are input from terminal a to b, and from terminals to the third coil Ile and fourth coil Ild. Figure 7 (
In a), the direction (
In mode ■), Fig. 7 10), the fourth magnetic pole 8 is placed on the terminal.
In the direction of exciting the second magnetic pole 8C to the terminal a in FIG. The state in which pulses are input in the direction of excitation (mode ■) is shown.

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 of Table 1 of Kyoshimo Kinpaku, in the case of mode ■, the magnetic force of the first S pole 8b on the N pole side is strong, and the magnetic force between the first magnetic pole 8b and the fixed tooth of the stator 9 is strong. The movable element 8 is held in a stable deaf state by the attractive force between the third and fourth S poles sa, s on the S pole side.
The phases of e are shifted by ]/4 pitch with respect to the fixed teeth of the stator 9, respectively. In mode ■, the magnetic force of the fourth magnetic pole 8e on the S-pole side becomes stronger, and the magnetic force of the fourth magnetic pole 8e on the S-pole side becomes stronger, and the fourth S-pole 8e of the movable element 8 is moved to the stator 9. It will move in the direction that matches the fixed tooth of , and will advance by 1/4 pitch. At this time, the first and second S poles 8b and 8c on the N pole side are out of phase by 1/4 pitch.

Furthermore, in mode ■, the mother side of the second magnetic pole 8c on the N-pole side becomes stronger, and the mover 8 moves in the direction where the second magnetic pole 8c matches the fixed tooth of the stator 9 in phase]/4 Advance the pitch,
The third and fourth S poles on the S pole side are out of phase by ]/4 pinch. In mode 2, the magnetic force of the third S pole 8d on the S pole side is strong, and the movable element 8 moves in the direction where the third S pole 8d matches the fixed tooth of the stator 9 in phase. 4
Pitch forward. Furthermore, return to mode ■ again and
The main side of the magnetic pole 8b becomes strong, and the movable element 8 advances by 1/4 pitch, reaching the 71st (A) state. In this way, by repeating the mode Φ to ■, the movement is made by #)]/4 pitches per pulse. In the case of this embodiment, two movers are used for one stator 9. 8 and 8 constitute a set of motors, but the operating principle is the same as the above-mentioned case of one movable element for one stator, and the combs move by 14 pitches per pulse. It's becoming a trap. By using two movers in this way, the propulsive force is doubled.

On the other hand, between the intermediate saddle 2 and the table body 3, there is also a track base 6 on the lower surface side of the table body 3. - A third stator 9C and a fourth stator 9d are arranged in the Y-axis direction in parallel with the movable elements 8 and 8.8 on the upper surface side of the intermediate saddle 2.
, 8 are installed. The mover 8 has a first arsenic on the N pole side which is arsenized by a permanent grinding stone 8a, similar to the above-mentioned mover.
magnetic pole 8b and second magnetic pole 8c, and a third S pole on the S pole side.
A pole 8d and a fourth magnetic pole 8e are formed, and a first coil 11a1 and a second coil are connected to each magnetic pole]b.

A third coil llc and a fourth coil lid are wound. Furthermore, this first coil lla, second coil]1b1 third coil llc and fourth coil ll
d is electrically connected to the pulse generation source, and the table body 3 is moved to the intermediate saddle 2 by the pulse from the pulse generation source.
In the figure, 12 is a bobbin, and 13 is a yoke.

Next, the operation of the XY table with a linear motor of this embodiment will be explained. First, when the table main body 3 is fast-forwarded in the xah direction, the first stator 9C or the second stator 9d on the base 1 A movable element 8 facing one of the two.
Input a pulse from a pulse generation source to 8, and drive the stator and mover of - pair. In this case, the mover moves by 4 pinches per pulse with respect to the stator, and the mover The table main body 3 is transferred by 1/4 pitch per pulse in the same direction in the Xah direction via the intermediate saddle 2 to which the table body 3 is attached.

Next, when performing fine movement feed, a pulse is input alternately to the movers 8, 8 facing the first stator 9C and the movers 8, 8 facing the second stator 9b. Stator 9
1/4 for a and second stator 9b, respectively.
Although it moves by a pinch, the phases of the fixed teeth of the first stator 9a and the second stator 9b are out of phase by 178 pitches, so
(alternately) (table body 3 by entering Luz)
is finely moved by 178 pinches in the X-axis direction, resulting in twice the resolution as in the - column.

Also, when moving the table body 3 in the Y-axis direction,
It is installed between the table body 3 and the intermediate saddle and is driven by a near motor in the same direction as the X-axis. Drive by inputting a pulse to the movable element facing either the third stator 9C or the fourth stator 9d, or alternately pulse the movable elements facing the two rows of stators 9C and 9d. Similarly, by inputting and driving, it is possible to select whether to feed at ]/4 pitch or fine movement at ]/8 pitch.

Note that the transfer speed of the table main body 3 becomes faster when the pulse frequency is increased, and becomes slower when the pulse frequency is lowered. Further, the transfer distance is adjusted by the number of input pulses aL'4.

Furthermore, even if a load is applied to the table body 3, the linear bearing 5. ... are preloaded, so there is no wobbling between the table body 3 and the intermediate saddle 2, and between the intermediate saddle 2 and the base], and furthermore, the ball rolling groove 5a and the load goal 5f Since the contact angle with the linear motor is around 45 degrees, it is possible to evenly support loads from four directions (up, down, left and right), the gap between the linear motor's mover and stator is kept constant, and the thrust is always held constant. Further, even when a load is applied to the table body 3, there is no risk of interference between the movable element and the stator, and therefore, the gap between the movable element and the stator can be narrowed, so that a large thrust and stopping force can be obtained.

In this embodiment, the stators are arranged in two rows, but they may be arranged in three rows, four rows, etc. In the case of three rows, the phase of the fixed teeth is set to 1/4 pitch of ]/3, or ]／】2 pitches,
In the case of 4 rows, it is 174 of /4 pilets, or J/16.
It is sufficient to shift the phase by a pinch, and the resolution can be tripled or quadrupled, respectively.

1. In the linear pulse smoke of this embodiment, the pulse unit moves by 174 pinches of the fixed tooth, but any motor that moves the pulse unit by a fixed amount may be used; The motor is not limited to a motor, and other types such as a linear DC motor or a linear synchronous motor may be used.

(Effect of the invention) 1 Haku 11 + 3. It consists of the structure and action on IJ,
By using linear bearings, the table body moves easily, and by using linear motors, there is no need to use ball screws, etc., reducing weight. Responsiveness when stopping is the same as above, and positioning accuracy is improved.

4 (z) In order to input pulses alternately to each movable element facing each stator, the amount of feed of one pulse when using one stator is also very small. Since it can be fed, fine movement or rapid movement can be performed as necessary, and the effect of extremely accurate positioning can be obtained.

Furthermore, unlike conventional ball screws, there is no twisting of the screw shaft or puncture lash between the screw shaft and the nut, so positioning accuracy is improved. A highly accurate XY table can be obtained.

Since it is possible to reduce the number of unused parts, it is possible to reduce costs, improve assembly accuracy, and furthermore, the structure is simplified, so it is possible to prevent the occurrence of failures, among other effects. is obtained.

[Brief explanation of the drawing]

Fig. 1 shows the plane factor of an XY table with a linear motor according to a simple embodiment of the present invention, and Fig. 2 shows the It-It of the device of the first factor.
3 (a), (b) and E are front views and plan views of the linear bearing of the device in FIG. 1, and sectional views along the harbor line, and FIG. and (c) are a plan view of the intermediate saddle of the device shown in Fig. 1, a cross-sectional view along the Rollo line ゜ and a cross-sectional view along the harbor line, and Fig. 5 (a) and (b) are the
A partially enlarged bottom view of the table body of the device shown in the figure, a cross-sectional view along the Rollo line in Figure 5 (A), and Figures 6 1 (A) and (B).
1 is an enlarged front sectional view and a Rolo line sectional view of the movable element and stator of the device shown in FIG. 1, and FIGS.
The operating principle of the linear pulse motor is shown in the schematic front view of the linear pulse motor. 6 Explanation of symbols 1...Base 2...Intermediate saddle: 3...
・Table body 5... Linear bearing 8... Linear motor mover 9... Linear motor stator Patent applicant Hiroshi Teramachi Figure 3 (Inno 5th point; C Ino ζ mouth)

Claims (1)

[Claims] An intermediate saddle is attached to the base via a linear bearing so as to be slidable in the X-axis direction, and a table body is attached to the intermediate saddle via a linear bearing in the Y-axis direction perpendicular to the X-axis. A linear motor consisting of a stator and a movable element is interposed between the intermediate saddle and the base and between the intermediate saddle and the table body, respectively. On either the upper surface or the lower surface of the intermediate saddle, a plurality of stators are arranged in parallel so that the fixed teeth of each are out of phase, and on the other side, a plurality of movers corresponding to the stators are arranged in parallel, A plurality of stators are arranged in parallel on either the top surface of the saddle or the bottom surface of the table body so that the fixed teeth of each stator are out of phase, and a plurality of movers corresponding to the stators are arranged in parallel on the other side. XY with linear motor featuring
table.