JPH0133294B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is applicable to X, Y, and Z axes in machine tools such as NC machines, automatic tool changers, automatic welding machines,
The present invention relates to a linear guide device that guides linear reciprocating motion in the sliding portion of general industrial machines such as injection molding machines and industrial robots.

[Conventional technology]

Conventionally, there has been a track base having a pair of ball transfer grooves along the longitudinal direction of both left and right shoulders, a slide base disposed above the track base, and a slide base provided on both left and right sides of the slide base. A linear guide device is known that includes a bearing having a large number of balls that transfer loads in the vertical and horizontal directions within each ball transfer groove of the track base.

In this type of linear guide device, the load acting on the slide table in the vertical and horizontal directions is applied by a large number of balls in the bearings installed between the slide table and the track base, so each of these balls is accurately controlled. By incorporating it between the slide table and the track base, there is an advantage that stable linear sliding and linear guidance can be performed.

[Problem that the invention seeks to solve]

However, a feeding mechanism for linearly sliding the sliding table along the track must be installed separately from this linear guide device, which increases the size of the device and also requires a separate feed mechanism. If a manual feed handle is used, it is difficult to make precise fine-feeds or determine the feed amount according to the purpose.
There is a problem in that rapid feed requires a lot of effort, and if an automatic feed mechanism using a servo motor is adopted as this feed mechanism, a gear reduction mechanism is required, resulting in a complicated structure, and In order to achieve high precision feed, it is necessary to increase the division precision of the encoder.If the encoder division precision is increased, the load on the servo motor itself will increase, resulting in the problem that it will not be possible to obtain minute high precision feed. be.

[Means for solving problems]

The present invention has been proposed in order to solve the above-mentioned problems in view of this point of view.Firstly, the first invention consists of a track base having ball transfer grooves along the left and right longitudinal directions; A sliding table is arranged above the way with a predetermined gap from the top surface thereof, and a sliding table is provided on both the left and right sides of the sliding table, and a load is applied to each ball transfer groove of the way. A stator having a large number of teeth extending in the width direction is attached to the top surface of the above-mentioned track base along the longitudinal direction of the track base. is a linear guide in which a mover having a plurality of excitation parts is mounted with a predetermined clearance maintained between the stator and the stator, and the stator and mover constitute a linear motor mechanism that drives the slide table. It is a device.

In principle, the linear guide device of the present invention incorporates a linear motor mechanism consisting of a stator and a mover between a track base and a sliding base, and this linear motor mechanism is a variable reluctance type. , a permanent magnet type, or a composite type combining these, but in order to obtain high precision and high thrust, it is preferable to have a permanent magnet and a plurality of permanent magnets at the tip of the excitation core facing the teeth of the stator. A composite type including a plurality of electromagnets with inductor teeth is preferable.

Furthermore, as a method for exciting the plurality of excitation parts incorporated in the movable element of the linear motor mechanism, there is a one-phase excitation method in which current is always passed through only one phase to the movable element excitation part to perform step feeding. Alternatively, a two-phase excitation method may be used in which a two-phase current is constantly applied to the movable excitation part to perform step feeding, but preferably a high thrust can be obtained;
Moreover, a two-phase excitation method is preferable because it has less damped vibration and can respond to a wide frequency range.

Regarding the track base and slide base in which the above-mentioned linear motor mechanism is incorporated, conventionally known ones can be adopted as they are, but preferably, the stator is used to control the thrust and holding force of the linear motor mechanism. And the clearance between the track base on which the movable element is attached and the sliding base can be adjusted.

As a means for adjusting the clearance between the track base and the slide base, the slide base and the bearing blocks of each bearing provided on the lower surface side on both the left and right sides of the slide base are formed separately, and the slide base is A method of inserting a shim between the sliding table and each bearing block to adjust the clearance between the stator and mover of the linear motor mechanism, and a method of interposing a shim to adjust the clearance between the stator and mover of the linear motor mechanism, and a method of interposing a shim between the sliding table and each bearing block, and a method of interposing a shim to adjust the clearance between the stator and mover of the linear motor mechanism, and There are methods such as adjusting the height by grinding, but these methods require disassembling the device when adjusting the clearance, which requires a great deal of effort.

The second invention solves this problem of clearance adjustment, in which the slide table is composed of a body main body and a taper gib.

That is, the second invention is the linear guide device according to the first invention, in which the sliding base is moved by a sliding tapered surface that is inclined along the front-back direction of the upper surface and a movable element of the linear motor mechanism in a predetermined front-back direction. Consisting of a body main body having a through hole that is loosely fitted while maintaining a space, and a taper gib that is movably attached to the sliding tapered surface of the body main body and to which the movable element is attached to the lower surface side, This is a linear guide device in which the clearance between the stator and the movable element of the linear motor mechanism can be adjusted by moving the taper gib in the longitudinal direction on the sliding tapered surface of the body main body.

Furthermore, in the linear guide devices of the first and second inventions, in order to perform stable linear sliding and linear guidance, the track base has a pair of ball transfer grooves along the left and right longitudinal directions, and also has a sliding groove. It is preferable that a large number of balls of the bearings provided on the left and right sides of the stand transfer the load in the vertical and horizontal directions within each ball transfer groove of the way, and that the way and the slide It is preferable that the bearing that loads the load be formed so that the preload can be adjusted.

As a means for adjusting the preload of the bearing in this way, for example, a bearing block of the bearing provided on at least one of the left and right sides of the slide table is formed separately from the slide table, and this bearing block is attached to an eccentric pin. There is a method of attaching it to the sliding table via.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, the linear guide device of this invention will be specifically explained based on an Example.

1 to 11, a linear guide device according to an embodiment of the invention is shown. This linear guide device includes a track 1 having a pair of ball transfer grooves 5 along the left and right longitudinal directions, and a sliding base disposed above the track 1 with a predetermined gap from the upper surface of the track 1. 2, each ball transfer groove 5 of the track base 1 is provided on both left and right sides of the sliding base 2.
From a bearing 3 having a large number of balls 26 that transfer loads while applying loads in the vertical and horizontal directions, a stator 7 attached to the track base 1 side, and a movable element 11 attached to the slide base 2 side. It is composed of a linear motor mechanism 4 that drives the slide table 2.

The track 1 has ball transfer grooves 5 on both sides thereof.
A stator 7 is provided along the longitudinal direction at the center of the upper surface of the rail 6, and the stator 7 has a large number of teeth 9 extending in the width direction.
is formed. Note that the track base 1 does not necessarily need to be formed of one rail 6, and the
As shown in FIG. 3, it may be formed into a split type consisting of a pair of rails 6 and a bolster 8.

On the other hand, the sliding table 2 has a movable element 11 of a linear motor mechanism 4 equipped with a plurality of excitation parts 10 with a predetermined clearance maintained between it and the stator 7 on the lower surface thereof, and child 7 and mover 11
It is designed to be driven by the magnetic action that acts between the

In this embodiment, the linear motor mechanism 4 composed of the stator 7 and the movable element 11 is a composite type that uses both variable reluctance and permanent magnets, and as shown in FIG. It includes a permanent magnet 12 and an exciting core 12'. Further, a plurality of inductor teeth 13 facing the teeth 9 of the stator 7 are formed on the lower surface of the tip of the excitation core 12'. Note that, as the excitation method for exciting the linear motor mechanism 4, a two-phase excitation method is adopted which can obtain a high thrust, has little damped vibration, and can respond to a wide frequency range.

In this embodiment, the linear motor mechanism 4
The relationship between the track base 1 and the sliding base 2, in which the linear motor mechanism 4 is installed, is such that the thrust and holding force of the linear motor mechanism 4 can be adjusted by adjusting the clearance between the stator 7 and the movable element 11. 1 and the sliding table 2 can be adjusted.

That is, as shown in FIGS. 5 and 6, the sliding tapered surface 14a of the sliding table 2 that slopes along the front-back direction of the upper surface and the movable element 11 maintain a predetermined movement space in the front-back direction. Through-hole 14b that can be fitted
a body main body 14 having
The taper gib 15 is movably attached to the sliding tapered surface 14a of the main body 14, and the movable element 11 is attached to the lower surface side of the taper gib 15. By moving 15 in the front-back direction, the clearance between the stator 7 and the movable element 11 of the linear motor mechanism 4 can be adjusted. In this case, a screw hole 16 is provided on the upper surface of the body main body 14, and a long hole 17 extending in the front-rear direction is formed in the taper gib 16, and the screw is connected to the screw hole 16 through this long hole 17. The body main body 14 is attached by the mounting bolt 18.
and the taper gib 15, and at this time, the tip of the push screw 21, which passes through the plate 20 fixed to the front and rear ends of the body body 14 by the fixing screw 19, is brought into contact with the taper gib 15. Taper give 15
The clearance between the stator 7 and the movable element 11 can be adjusted by moving the movable element 11. As a result, the clearance between the stator 7 and the movable element 11 can be adjusted to the minimum to maximize thrust and holding force, and the movable element 11 can be positioned within the through hole 14b of the body main body. As a result, the entire structure can be made thin and compact, improving stability, and the movable parts can be made lighter.
Since the inertial force can be reduced accordingly,
Improves responsiveness and accuracy of linear guidance movement.

On the other hand, the bearing 3 is shown in FIGS.
As shown in FIGS. 1 and 4, a bearing block 24 is attached to both left and right sides of the sliding table 2 with bolts 22 or eccentric pins 23, and side covers are attached to both end surfaces of the bearing block 24. 25, and a large number of balls 26 that are transferred while applying a load inside each ball transfer groove 5 of the track base 1.
It is composed of a retainer 27 that holds each of these balls 26, and is capable of applying vertical and horizontal loads acting on the sliding table 2. Therefore, in this embodiment, even if vertical and horizontal loads are applied to the sliding table 2, the clearance between the stator 7 and the mover 11 does not change, and the holding force is always stable. and can be obtained.

In the above embodiment, a case has been described in which the bearing blocks 24 of the bearings 3 provided on both left and right sides of the slide table 2 are formed separately from the slide table 2, but they do not necessarily have to be separate bodies. Without,
For example, as shown in FIG. 12, the sliding table 2 and the bearing block 24 of each bearing 3 may be formed integrally.

〔Effect of the invention〕

According to the linear guide device of the present invention, the stator is attached to the upper surface of the track base, and the lower surface of the slide base is provided with a plurality of excitation parts while maintaining a predetermined clearance between the slide base and the stator. The stator and movable element form a linear motor mechanism that drives the sliding table to perform linear reciprocating motion of the sliding table, so there is no need to provide a separate feeding mechanism. , it is possible to reduce the size of the device. Moreover, unlike the conventional saddle type, there is no motor coupling screw shaft, making the movable parts lighter, and since there is no rotating part like a screw shaft or coupling motor, the response is good.
Further, it is possible to achieve accurate fine movement feed and a feed amount according to the purpose with high precision. In addition, since it uses rolling contact using balls, there is less wear and tear.
In addition, since the distance between the track base and the sliding base is kept constant, the thrust and holding force of the linear motor mechanism are stable, making it possible to provide a linear guide device that exhibits stable thrust and holding force. .

[Brief explanation of drawings]

FIG. 1 is a plan view of a linear guide device according to an embodiment of the present invention, FIG. 2 is a side view of FIG. 1, and FIG.
Figure 4 is a front view, Figure 4 is a sectional view taken along the line - in Figure 1,
Figure 5 is a cross-sectional view taken along the - line in Figure 1, and Figure 6 is a cross-sectional view of Figure 1.
Fig. 7 is a plan view showing the bearing shown in Fig. 1, Fig. 8 is a side view of Fig. 7,
Figure 9 is a cross-sectional view taken along the - line in Figure 7, Figure 10 is a cross-sectional view taken along the - line in Figure 7, and Figure 11 is a cross-sectional view taken along the - line in Figure 8.
12 is a sectional view showing a modified example of the slide table, and FIG. 13 is a partial perspective view showing a modified example of the track base. Explanation of symbols 1...Railway platform, 2...Sliding platform, 3
...Bearing, 4...Linear motor mechanism, 5...
...Ball transfer groove, 6...Rail, 7...Stator,
8... Bolster, 9... Teeth, 10... Excitation part,
11...Mover, 12...Permanent magnet, 12'...
Excitation core, 13... Inductor tooth, 14... Body main body, 14a... Sliding taper surface, 14b... Through hole,
15... Taper gib, 16... Screw hole, 17...
Long hole, 18...Mounting bolt, 19...Fixing screw,
20...Plate, 21...Push screw, 22...
Bolt, 23... Eccentric pin, 24... Bearing block, 25... Side cover, 26... Ball, 27
...Retainer.

Claims (1)

[Scope of Claims] 1. A track base having ball transfer grooves along the left and right longitudinal directions, and a stator having a large number of teeth extending in the width direction on the upper surface thereof, and a stator above the track base. A sliding base is disposed with a predetermined gap from the upper surface, and has a movable element on the lower surface side that together with the stator constitutes a linear motor mechanism for driving the sliding base, and this sliding base. and a bearing having a large number of balls that are installed on the left and right sides of the track base and transfer a load through each ball transfer groove of the track base, and the slide base is tilted along the front-rear direction of the upper surface thereof. A body body having a sliding taper surface and a through hole into which the mover of the linear motor mechanism loosely fits while maintaining a predetermined movement space in the front-rear direction, and the body body is movably attached to the sliding taper surface of the body body. and a taper gib to which the movable element is attached on the lower surface side, and the taper gib is moved in the front and back direction on the sliding tapered surface of the body main body to increase the clearance between the stator and the movable element of the linear motor mechanism. A linear guide device characterized by adjustment. 2. The wayway has a pair of ball transfer grooves along its left and right longitudinal directions, and a large number of balls of bearings provided on both left and right sides of the slider move inside each ball transfer groove of the wayway in the vertical and horizontal directions. A linear guide device according to claim 1, which transfers a load while being applied. 3. The linear guide device according to claim 1 or 2, wherein the slide table and the bearing block constituting each bearing are integrally formed. 4. According to any one of claims 1 to 3, wherein the track base is composed of a pair of rails having a ball transfer groove and a bolster located between the pair of rails and having a stator on the upper surface. The linear guide device described.