JPH10263960A - Machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a machine tool which can secure the necessary areal duplication of each stator and each moving element, and the necessary length of each stator without increasing the weights of an X slide and a Y slide, and also making them large in size, can actualize to quickly accelerate/decelerate shaft driving, and also can avoid the degradation of processing accuracy due to vibration. SOLUTION: In this machine tool, each linear motor 20 is interposed between a Y slide 5 which is supported by a X slide 4 in such a way that it can be moved along vertical frame parts 4a and 4b, and each vertical frame part 4a and 46, and the Y slide 5 is thereby driven by each linear motor 20 so as to be propelled. In this case, the stator 21 of each linear motor 20 is arranged in the inner side surfaces of the vertical frame parts 4a and 4b, a motor mounting part projected toward an upper frame part 4c is formed in the Y slide 5, each moving element 22 is arranged in the outer side surface of a motor mounting part 33 in such a way as to be faced to the stator 21, an escape part 30 to which the motor mounting part of the Y slide 5 is advanced in, is formed in an upper frame part 4c, and the stator 21 disposed in each vertical frame part 4a and 4b is extended to the escape part 30 so as to be disposed thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machine tool using a linear motor for a feed device.

[0002]

2. Description of the Related Art In machining small workpieces with a machine tool (for example, a machining center), there are many short-distance movements that must be decelerated before the moving speed reaches a maximum speed during a positioning operation. Therefore, in such a feeder, it is important that the acceleration is larger than the maximum speed (the acceleration / deceleration time is short). However, the conventional ball screw drive system has a structure in which the driving force of the servo motor is transmitted via the ball screw, has low efficiency, and has a limit in increasing acceleration.

[0003] For this reason, a non-contact, frictionless linear motor has recently been adopted as a feeder. This linear motor is configured such that a moving element is disposed so as to face a stator disposed over the entire length of a shaft moving stroke with a predetermined gap therebetween, thereby obtaining a thrust. When such a linear motor is used, the transmission efficiency of the motor power is higher than that of a conventional ball screw drive system, so that a large acceleration of 1 to 1.5 G can be obtained in the case of a machining center. .

[0004] By the way, a large thrust is required to rapidly drive a heavy moving member to accelerate or decelerate. However, the thrust of the linear motor is proportional to the opposing area (overlapping area) of the moving element and the stator. In order to achieve this, the motor becomes large and a large mounting area is required, and the whole machine becomes large. In this case, since the width of a commercially available linear motor is generally constant, it is necessary to increase the length of the moving element in order to obtain a large thrust. On the other hand, since the length of the stator is determined by the sum of the length of the above-mentioned mover and its movement stroke, if the length of the mover is increased to obtain a large thrust, the length of the machine in the stroke direction becomes longer. Become.

In the above-described linear motor, the stator and the moving element must be fixed to the machine body while maintaining a predetermined interval over the entire length of the axial movement stroke. Since the force acts, it is necessary to increase the rigidity of the mounting portion, and from this point too, the weight tends to increase.

Further, in the control system, since the linear scale is used for detecting the position and the speed, the adverse effect of the mechanical vibration on the servo system becomes a problem. In adopting the linear motor, the machine rigidity is sufficiently ensured and the weight of the machine body is reduced. It is necessary to plan.

In order to secure a large thrust without increasing the length of the mover, a plurality of linear motors must be arranged in parallel, but this increases the motor weight and complicates the control.

[0008] In response to each of these problems,
The present applicant disposes a Y slide in a rectangular frame-shaped X slide so as to be movable in the vertical direction, and attaches the X slide to the Y slide.
A slide frame part surrounding the left and right vertical frame parts of the slide is formed, a stator is arranged on the outer surface of each vertical frame part of the X slide, and a moving element is arranged on the inner surface of the slide frame part of the Y slide. Machine is proposed (Japanese Patent Application No. 8-76191)
No., Japanese Patent Application No. 8-76210).

According to the machine tool according to the above proposal, the X slide has a so-called double column structure having a pair of left and right vertical frames, so that rigidity can be improved, and a stator is provided on the outer surface of the vertical frame. Since the stator is disposed, the stator can be disposed over the entire length of the vertical frame portion, and the necessary thrust and moving stroke can be secured without increasing the height of the machine in the stroke direction, whereby rapid acceleration / deceleration driving can be realized.

[0010]

However, in the above-mentioned proposal, since the slide frame surrounding each vertical frame is formed on the Y slide, the weight of the entire Y slide increases and the size of the Y slide is easily increased. There is.

In the above-mentioned proposal, the linear motor is disposed between the outer surfaces of the left and right vertical frames separated to the left and right and the slide frame of the Y slide surrounding the vertical frames. Therefore, the driving unit is located at the left of the center of gravity of the Y slide,
Since it is located right away, vibration is likely to occur from this point, and there is a concern that the vibration will adversely affect machining accuracy.

Here, in order to reduce the weight and size of the Y slide and to avoid the problem of vibration, a stator is disposed on the inner surface of each vertical frame of the X slide, and the outer surface of the Y slide is provided. It is conceivable to dispose the mover in the area. In such a case, the slide frame portion of the Y slide can be made unnecessary, and the drive unit can be arranged near the center of the Y slide, thereby avoiding the adverse effect on the processing accuracy due to the vibration.

However, in the case of the structure in which the stator is disposed on the inner side surface of the X slide, it is necessary to extend the vertical length of the vertical frame portion in order to secure the necessary length of the moving member and the necessary moving stroke. As a result, the weight and the size of the entire X slide increase, and the same problem as described above may occur.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and does not increase the weight and size of the X-slide and the Y-slide, and does not cause the required overlapping area of the stator and the moving element, and the required length of the stator. It is an object of the present invention to provide a machine tool which can secure a sharp acceleration / deceleration axis drive and can avoid deterioration of machining accuracy due to vibration.

[0015]

According to a first aspect of the present invention, there is provided a rectangular shape in which one end of a pair of first and second frame portions and the other end portion are connected by a third frame portion and a fourth frame portion. A frame-shaped column member, and a slide member disposed so as to pass through the column member and supported by the column member so as to be movable along the first and second frames. And a linear motor disposed between the first and second frame portions, and the linear motor drives the slide member by propulsion. A stator for a linear motor is provided, a motor mounting portion is formed on the slide member so as to project toward at least one of the third and fourth frame portions, and a movable member is mounted on an outer surface of the motor mounting portion with the stator. And at least the third and fourth frame portions are provided. On the other hand, to form a relief portion for the motor mounting portion of the slide member enters, the first,
The present invention is characterized in that the stator arranged in the second frame portion is extended to the relief portion.

According to a second aspect of the present invention, in the first aspect, the column member is formed by connecting the upper ends of a pair of left and right vertical frames to each other.
The lower end is joined by an upper frame and a lower frame to form an X slide supported by a vertical bed so as to be movable in the X-axis direction, and the slide member is disposed so as to pass through the X slide. A Y-slide supported movably in the Y-axis direction by the X-slide, a linear motor stator is disposed on an inner surface of the vertical frame portion, and a motor mounting portion is formed on the Y-slide to protrude upward. A mover is disposed on the outer surface of the motor mounting portion so as to face the stator, and an escape recess for the motor mounting portion to enter is formed in the upper frame portion, and is disposed in the vertical frame portion. The extended stator is extended to the escape recess.

In the present invention, among the components of the linear motor, those which are attached to a fixed member (a member for movably supporting a mating member such as a column member or an X slide of the present invention) are referred to as a stator. A member attached to a movable member (a member movably supported by a mating member such as a slide member or a Y slide according to the present invention) is referred to as a mover.

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 8 are views for explaining a machine tool according to an embodiment of the present invention,
FIG. 1 is a perspective view of an assembled state of an X slide, a Y slide, a Z slide and a bed, and FIGS. 2 to 5 are perspective views, front views, and cross-sectional right side views of an assembled state of an X slide, a Y slide and a Z slide, respectively. Top view, FIG. 6 shows Y slide and Z
FIG. 7 is a perspective view of a slide assembly, FIG. 7 is a sectional view of a rail and a guide, and FIG. 8 is a schematic configuration diagram of a linear motor.

In the figure, reference numeral 1 denotes a machine tool main body, which is provided with a processing table (not shown) in front of the vertical bed 2 (on the front side as viewed from the front of the machine), and is mounted and fixed to the processing table. Three axes (X
(Y axis, Y axis, Z axis).

A column-shaped X is provided on the front of the vertical bed 2.
A slide 4 is movably supported in the X-axis direction (horizontal horizontal direction when viewed from the front of the machine), and a Y slide 5 is supported on the X slide 4 so as to be movable in the Y-axis direction (vertical direction). . A tool (not shown) is attached to the Y slide 5.
A Z-slide 6 which constitutes a ram rotatably supporting the main shaft 3 on which is mounted is supported so as to be movable in a Z-axis direction (a front-back direction when viewed from the front of the machine). The slides 4, 5, and 6 are formed of a light metal material such as an aluminum alloy. A counter balance cylinder 40 is disposed on the left and right sides of the X slide 4, thereby reducing the couple acting on the Y slide 5.

The vertical bed 2 has a substantially L shape when viewed from the left side and a rectangular frame shape when viewed from the front. A rail 10 extending in the X-axis direction is provided at the lower portion of the front surface of the upper frame portion 2a of the vertical bed 2, and two rails 10 extending in the X-axis direction are provided on the upper surface of the lower frame portion 2b projecting forward. , 10 are arranged parallel to one another.

The X slide 4 has a pair of left and right vertical frames 4a and 4b whose upper ends are connected by an upper frame 4c and whose lower ends are connected by a lower frame 4d in a front view. It has a vertically long rectangular frame shape. Here, the lower frame portion 4d
Is set to be the same as the front and rear widths of the vertical frame portions 4a and 4b, whereas the front and rear width of the upper frame portion 4c is set smaller than the front and rear widths of the vertical frame portions 4a and 4b. As a result, an escape recess 30 is formed at the front of the upper frame 4c.

Two guides 11 slidably engaged with the rail 10 are provided on the back surface of the upper frame 4c of the X slide 4.
Are arranged at intervals. X slide 4
Guides 11 are slidably engaged with the rails 10 at four corners on the bottom surface of the lower frame portion 4d. A Y slide 5 is provided on the lower surface of the upper frame 4c and the upper surface of the lower frame 4d.
The stoppers 9, 9 for restricting the amount of movement of the Y-axis are formed to protrude.

Each of the rails 10 is, as shown in FIG.
A rod body having a substantially I-shaped cross section, and the upper frame portion 2a or the lower frame portion 2b is bolted by a bolt 12 inserted in the center in the width direction.
Is fixed. Each of the guides 11 has a substantially C-shaped cross section, and is in rolling contact with the rail 10 with a ball 13 interposed therebetween. Each of the guides 11 is fixed to the upper frame 4c or the lower frame 4d of the X slide 4 by bolts 14, 14. The rail 10 and the guide 11 allow the X slide 4 to move only in the X axis direction, and restrict the movement in the Y axis and Z axis directions.

The stators 21 and 21 of the linear motor 20 are arranged in parallel with the rails 10 between the rails 10 on the upper frame 2a and the lower frame 2b of the vertical bed 2 by bolting or bonding. The rear surface of the upper frame 4c of the X slide 4 and the lower frame 4d
The moving elements 22, 22 of the linear motor 20 are arranged and fixed to the bottom surface of the linear motor 20 by bolting or bonding, respectively.

Rails 31, 31 are fixed to the front surfaces of the vertical frame portions 4a, 4b by bolts, and each of the rails 31 has a length from the vicinity of the upper surface of the lower frame portion 4d to the upper end of the vertical frame portions 4a, 4b. Have.

The Y slide 5 has a tubular box frame 15 having a rectangular cross section having a rectangular through-hole 15a into which the Z slide 6 is inserted. And a slide frame portion 33 fixed at a right angle.

The box frame 15 of the Y slide 5 is
It penetrates through the slide 4 and projects rearward. Further, the slide frame portion 33 has a rectangular plate-like slide wall 33 in front view.
The left and right sides of the motor holding wall 33b and the left and right sides of the box frame 15 are flush with each other. And a motor holding surface 15b. Reference numeral 36 denotes an opening for reducing the weight, and reference numeral 37 denotes a cavity formed by forming the motor holding wall 33b into a U-shape, and the weight is reduced from this point as well.

Here, the slide wall 33a and the motor holding wall 33b are formed so as to extend upward from the upper surface of the box frame portion 15, and the motor holding wall 33b is Y
When the slide 5 moves to the upper end position in the Y-axis direction, the slide 5 is located in the escape recess 30.

The left and right edges of the slide wall 33a overlap the front surfaces of the vertical frame portions 4a and 4b, and the rear surface of each overlap portion includes a pair of upper and lower members slidably engaged with the rails 31. Guides 34, 34 are fixed respectively.
The mounting structure of the rail 31 and the guide 34 is the same as the structure of the rail 10 and the guide 11.

The inner surface 4 of each of the vertical frame portions 4a, 4b
The stator 21 of the linear motor 20 is arranged and fixed to 4a and 44b by bolting or bonding. Here, each of the stators 21 has an extension surface 30a, 3 of the inner side surface 44a, 44b formed by providing the escape recess 30.
0b. The moving member 22 is fixed to the motor holding surface 15b extending over the left and right outer surfaces of the motor holding wall 33b and the left and right outer surfaces of the box frame 15 by bolting or bonding. Reference numeral 22 faces the stator 21 with a predetermined gap.

The Z slide 6 is constructed by inserting and holding the main shaft 3 into the axis of a rectangular parallelepiped slide body 6a which is inserted into the through hole 15a of the box frame 15 so as to be able to move forward and backward.

Although not shown, the left and right outer surfaces of the slide body 6a of the Z slide 6 and the box frame 1 of the Y slide 5
On the left and right inner side surfaces of the through hole 15a, a moving member and a stator having the same structure as the moving member 22 and the stator 21, respectively, are arranged so as to face each other at a predetermined interval, and are fixed similarly. ing.

Each of the linear motors 20 is a synchronous type linear motor, and has a strip-shaped stator 21 having a length corresponding to the axial movement stroke of each of the slides 4, 5, and 6; And a moving element 22 that faces with a gap. In addition, as the above linear motor,
Of course, a pulse type or an induction type can also be adopted.

The stator 21 of each linear motor 20 is
As shown in FIG. 8, a large number of field magnets 24 alternately magnetized in the longitudinal direction with N poles and S poles are arranged at equal intervals on the upper surface of the magnet fixing plate 23 and fixed with an adhesive. 24 are molded with a resin member (not shown). The moving element 22 of each linear motor 20
Is the stator 21 of the flat plate 25 formed by stacking silicon steel plates.
A plurality of grooves 25a extending in a direction perpendicular to the moving direction are formed on the opposing surface 22a, and an armature coil 26 is inserted into each of the grooves 25a and molded with a resin member.

Next, the operation and effect of this embodiment will be described. In the machine tool 1 according to the present embodiment, when a current is supplied to each of the moving elements 22 of the linear motor 20, a thrust is generated between the moving element 22 and the stator 21. , Z slide 6 are the X axis, Y
It relatively moves in the axis and Z-axis directions.

In the present embodiment, the escape recess 30 is formed on the front surface of the upper frame portion 4c of the X slide 4, whereby
Extension surfaces 30a, 30b extending continuously from the inner surfaces 44a, 44b of the left and right vertical frame portions 4a, 4b are provided.
Is a length reaching the upper ends of the extension surfaces 30a, 30b. Further, the motor holding wall 33b of the Y slide 5 is formed so as to protrude so as to enter the escape recess 30. 15, so that it is possible to secure a large thrust while securing the necessary Y-axis stroke without increasing the height of the X slide 4.
As a result, it is possible to realize axial feed by rapid acceleration / deceleration drive.

That is, in order to secure a large thrust, it is necessary to increase the overlapping area between the moving element 22 and the stator 21.
If an attempt is made to secure the shaft stroke, the height of the X slide 4 will increase, and there is a concern that the machine will become large. In the present embodiment, since the motor holding wall 33b is projected upward from the upper surface of the box frame 15, the area of the movable member 22 can be increased to increase the thrust, and the X-slide 4 has the recess 3
0 is formed, and the motor holding wall 33b is made to enter here. Therefore, it is possible to avoid the interference with the motor holding wall 33b projecting upward without increasing the height of the X slide 4, and to make necessary Y The shaft stroke can be secured.

In this embodiment, since the linear motor 20 is arranged between the inner surface of each of the vertical frame portions 4a and 4b of the X slide 4 and the outer surface of the Y slide 5, the vertical frame portion is provided on the Y slide. The weight and size of the Y slide 5 can be reduced as compared with the case where a slide frame portion to be inserted is formed.
Vibration when starting and stopping in the axial direction can be suppressed, and machining accuracy can be improved. Furthermore, the linear motor 20 can be arranged near the center of the Y slide 5, and from this point, vibration can be suppressed and machining accuracy can be improved.

In the above embodiment, the case where the escape recess 30 is formed in the upper frame 4c of the X slide 4 has been described. However, in the present invention, the escape recess may be formed in the lower frame 4d.
Furthermore, escape recesses may be formed in both the upper frame portion 4c and the lower frame portion 4d. When the escape recess is formed in the lower frame portion 4d, the motor holding wall 33b is made to protrude below the lower surface of the box frame portion 15, so that the moving member 22 has a length extending over the projecting portion. In the case where escape recesses are formed in both the upper frame portion and the lower frame portion and the motor holding wall is formed so as to protrude upward and downward, the overlapping area between the mover and the stator can be further increased, and the size can be further increased. Thrust can be obtained.

In the above embodiment, the escape recess 30 having a U-shape in plan view is formed on the front surface of the upper frame portion 4c. However, the shape of the escape portion of the present invention is not limited to this. For example,
As shown in FIGS. 9 to 11, the upper frame portion 4c of the X slide 4
An escape opening 30 ′ may be formed through the hole, and the motor holding wall 33 b ′ of the Y slide 5 may be set in a shape that can enter the escape opening 30 ′. The effect of is obtained.

In the above embodiment, the stator 21 attached to the inner surfaces of the vertical frames 4a and 4b of the X slide 4 is the field magnet 24 and the like, and the movable member 22 attached to the motor holding surface 15b of the Y slide 5. In the present invention, the armature coil 26 and the like are provided on the X slide side, and the field magnet 24 is provided on the Y slide side.
May be arranged. In this case, there is an effect that cooling for measures against heat generation of the motor of the Y slide 5 becomes unnecessary. In the above embodiment, the description of the cooling device is omitted.

The Y slide 5 moves in both the X axis direction and the Y axis direction, while the X slide 4 moves only in the X axis direction. Therefore, when the armature coil 26 and the like are attached to the X slide 4 side as described above, the wiring of the power supply cable to the armature coil 26 is provided on the X slide 4 side that moves only in the X-axis direction. It will be easier.

[0044]

As described above, according to the machine tool of the present invention, the linear motor stator is mounted on the inner surfaces of the first and second frame portions (left and right vertical frame portions) of the column member (X slide). The slider is disposed on the outer surface of the motor mounting portion of the slide member (Y slide), so that the weight and size of the slide member can be reduced, and the drive unit is provided near the center of gravity of the slide member. There is an effect that the arrangement can be performed, vibration accompanying the movement of the slide member can be suppressed, and processing accuracy can be improved.

Further, since the motor mounting portion is formed so as to protrude in the moving direction and the mover is disposed at the motor mounting portion, the overlapping area of the mover and the stator, and consequently, the thrust can be increased, and the rapid acceleration / deceleration shaft feed can be performed. There is an effect that can be realized.

Further, the motor mounting portion projecting from any of the third and fourth frame portions (the upper frame portion and the lower frame portion) of the column member (X slide) can enter, that is, the motor mounting portion can be inserted. A relief part is formed to avoid the interference of the shaft member, and the stator is extended to the relief part. Therefore, the necessary axial stroke can be secured without increasing the length of the column member in the sliding member moving direction, and the weight of the column member is reduced. Therefore, there is an effect that an increase in the size of the entire machine can be avoided.

The projecting motor mounting portion can enter any one of the third and fourth frame portions (upper frame portion, lower frame portion) of the column member (X slide). By forming a relief portion for avoiding the interference of the above, when machining the motor mounting portion of the column member, the tool can easily enter and retract, and productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a machine tool according to an embodiment of the present invention as viewed from an oblique front.

FIG. 2 shows an X slide, a Y slide and a Z slide of the machine tool.
It is the perspective view seen from the slanting front of the slide assembly state.

FIG. 3 is a front view showing an assembled state of the X slide, Y slide and Z slide.

FIG. 4 is a cross-sectional right side view of the assembled state of the X slide, Y slide and Z slide.

FIG. 5 is a plan view showing an assembled state of the X slide, the Y slide, and the Z slide.

FIG. 6 is a perspective view of the assembled state of the Y slide and the Z slide as viewed obliquely from the front.

FIG. 7 is a sectional view showing an engagement structure of a rail and a guide of the machine tool.

FIG. 8 is a schematic configuration diagram of a linear motor of the machine tool.

FIG. 9 is a front view of a modified example of an assembled state of the X slide, the Y slide, and the Z slide.

FIG. 10 is a plan view of a modified example of an assembled state of the X slide, Y slide and Z slide.

FIG. 11 is a sectional right side view of a modified example of the X slide, the Y slide, and the Z slide in an assembled state.

[Explanation of symbols]

 Reference Signs List 1 machine tool 4 X slide (column member) 4a, 4b left and right vertical frame parts (first and second frame parts) 4c, 4d upper and lower frame parts (third and fourth frame parts) 5 Y slide (slide 15b Motor holding surface (outer surface of motor attachment portion) 20 Linear motor 21, 22 Stator, mover 30 Escape recess (escape portion) 30 'Escape opening (escape portion) 33b Motor holding wall (motor attachment portion)

Claims (2)

[Claims] 1. A rectangular frame-shaped column member formed by connecting one end of a pair of first and second frame portions and the other end portion of the pair of first and second frame portions with a third frame portion and a fourth frame portion. And a slide member movably supported along the first and second frame portions by the column member. The slide member and the first and second frame portions are In a machine tool in which a linear motor is disposed therebetween and the slide member is driven by the linear motor,
A stator for a linear motor is provided on the inner surface of the second frame, and a motor mounting portion is formed on the slide member so as to project toward at least one of the third and fourth frame portions. A mover is disposed on the side surface so as to face the stator, and at least one of the third and fourth frame portions is formed with a relief portion into which the motor mounting portion of the slide member enters. A machine tool, wherein a stator arranged in a second frame portion is extended to the relief portion. 2. The method according to claim 1, wherein the column member is
The upper and lower ends of a pair of left and right vertical frames are connected by an upper frame and a lower frame to form an X slide supported by a vertical bed so as to be movable in the X-axis direction. A Y-slide arranged to be inserted through the X-slide and supported by the X-slide so as to be movable in the Y-axis direction, and a stator of a linear motor is disposed on an inner surface of the vertical frame portion; A motor mounting portion is formed on the Y slide so as to protrude upward, and a mover is disposed on an outer surface of the motor mounting portion so as to face the stator, and the motor mounting portion enters the upper frame portion. A machine tool, wherein a relief recess is formed, and a stator arranged in the vertical frame portion is extended to the relief recess.