JPH08318432A - Electric discharge machine - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain an electric discharge machine in which a machining head and a workpiece maintain verticality even when the ram overhangs in a ram moving electric discharge machine. [Structure] The curved mounting portion 12 of the ram horizontal portion 1c is processed so as to be curved, and the portion corresponding to the curved mounting portion 12 of the Y-axis direction guide rail 5A is also made into a curved surface. By making the inclination that the portion 1a inclines due to an overhang be the same, the inclination amount is canceled and the perpendicularity between the processing head 2 and the comparative object 10 is corrected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric discharge machine equipped with a movable machining head capable of preventing a reduction in machining accuracy caused by deformation of a ram due to its own weight when the ram overhangs. is there.

[0002]

2. Description of the Related Art FIG. 10 is a configuration diagram showing a configuration of a conventional electric discharge machine, in which 1 is a ram composed of a vertical portion 1a and a horizontal portion 1b, and 2 is a machining head mounted on the ram 1. Reference numeral 3 is a guide rail guide for moving the ram 1 in the X-axis direction via an X-axis direction guide rail 4 which is a linear guide mechanism, and in the Y-axis direction via a Y-axis direction guide rail 5 which is a linear guide mechanism. Saddle as a part, 6 is a column, 7 is a head on which the column 6 and the processing tank 8 are loaded, 9 is an electrode mounted on the processing head 2, and 10 is a position in the processing tank 8 facing the electrode 9. Is the work piece installed in.

In such a conventional electric discharge machine, since the machining head 2 is installed in the ram vertical portion 1a, the spatial distance between the electrode 9 and the saddle 3 is shortest, as shown in FIG. 10 (a). When the Y-axis direction guide rail 5 is not moved in the longitudinal direction (hereinafter referred to as an overhang) so that the spatial distance gradually becomes longer from the reference position that becomes, the electrode 9 is applied to the workpiece 10 to be processed. Although kept perpendicular to the ram 1, as shown in FIG. 10B, when the ram 1 largely moves in the Y-axis direction (left direction in the drawing) and overhangs, the ram 1 and the machining head 2 The electrode 9 tilts δ with respect to the workpiece 10 due to its own weight. In order to obtain high processing accuracy of the workpiece 10, the processing head 2
Is required to maintain verticality at all times, and the machining head 2 does not move in the vertical direction unless verticality is achieved.
Machining in the depth direction (Z-axis direction) is not possible and dimensional accuracy is poor. Therefore, it is necessary to maintain the verticality of the processing head even when it overhangs.

As a technique for maintaining the verticality of the machining head 2 when the ram 1 overhangs, the rigidity of the ram 1 is increased to cope with the inclination θ of the ram 1 and the machining head 2 due to its own weight. . Generally, the rigidity of the ram 1 is determined by the moment of inertia of area (width x height ³ /
12), the means for increasing the rigidity of the ram 1 may be to increase the height in the Z-axis direction. Therefore, conventionally, as a technique for maintaining the verticality of the machining head 2 even when the ram 1 overhangs, a reinforcing plate 11 is fixed to the ram 1 as shown in FIG. 11, and as a result, the rigidity of the ram 1 is increased. There has been proposed an electric discharge machine in which the height in the Z-axis direction of the portion where is required to be increased is increased to increase the moment at the cross-section, that is, the rigidity. The reinforcing plate 11 increases the height in the Z-axis direction, increases the rigidity of the ram vertical portion 1a, and even when the ram 1 moves in the Y-axis direction (left direction in the drawing) and overhangs, the machining head 2 Is prevented, and the verticality of the processing head 2 is maintained.

[0005]

In the conventional electric discharge machine as described above, since the height in the Z-axis direction is increased by the reinforcing plate 11 as described above, the rigidity of the ram vertical portion 1a is increased, and the ram vertical portion 1a is increased. The inclination when 1 overhangs decreases. However, since the reinforcement plate 11 is newly added, the ram 1
There was a problem in that the weight of the
Further, in order to obtain higher rigidity, it is necessary to increase the width (X-axis direction) by thickening the reinforcing plate 11. If the weight of the reinforcing plate 11 increases, the capacity of the motor 23 required to move the ram 1, the reinforcing plate 11 and the processing head 2 in order to process the workpiece 10 must be increased. There were also problems.

The present invention has been made to solve the above problems, and a first object thereof is to perform electric discharge machining capable of correcting the inclination due to overhang of a ram without using a reinforcing plate. To get the opportunity. A second object is to obtain an electric discharge machine that does not require the inclination of the guide rail to be preset in addition to the first object. Further, a third object is to obtain an electric discharge machine capable of automatically adjusting the inclination of the guide rail according to the moving amount of the overhang, in addition to the second object. Furthermore, the fourth purpose is that precision is not required for creating the inclination of the guide rail set in advance,
However, after mounting the guide rail on the ram, it is necessary to correct it to obtain an electric discharge machine that can obtain a highly accurate inclination. Further, in addition to the above-mentioned first object, a fifth object is to obtain an electric discharge machine capable of automatically adjusting the inclination according to the amount of movement of the overhang of the machining head without the worker himself / herself working. That is.

[0007]

SUMMARY OF THE INVENTION In an electric discharge machine according to the present invention, a machining head supporting an electrode facing a workpiece, a ram vertical portion on which the machining head is mounted, and a ram vertical portion are suspended. A ram horizontal portion to be provided, which moves the ram in parallel, guide means for processing the workpiece placed in the processing tank by the electrode into an arbitrary shape, and when the ram is translated, Inclination means for inclining the ram in a direction for canceling the inclination generated in the processing head is provided.

Further, a machining head supporting an electrode for machining a workpiece, a ram vertical portion on which the machining head is mounted,
And a ram having a ram horizontal portion that vertically extends the ram vertical portion so as to face the workpiece placed in the processing tank, and is fixed to a lower surface of the ram horizontal portion of the ram,
A guide rail that gradually inclines upward from a reference position where the spatial distance from the electrode is the shortest to a position where the spatial distance is the longest, and a guide rail guide portion that guides the ram in the longitudinal direction of the guide rail. And ,.

Further, the upward inclination of the guide rail is
The guide rail and the electrode are formed by a curve forming means that pulls up an end portion of the guide rail on the side where the spatial distance between the guide rail and the electrode is longest.

Further, the curve forming means includes a moving amount detecting means for detecting a moving amount of the machining head along the guide rail,
The guide rail end portion is pulled upward in accordance with the movement amount detected by the movement amount detection means, and a forming means for forming an upward inclination is provided.

Furthermore, the upward inclination of the guide rail is the upward inclination provided in advance on the guide rail and the guide on the side where the spatial distance between the guide rail and the electrode is the longest due to the bending adjusting means. The adjustment inclination is generated when the rail end is pulled up.

A counter that moves relatively in a direction opposite to the moving direction of the working head according to the moving amount of the working head along the guide rail and gives a moment to the working head according to the moving amount. It has a weight.

[0013]

In the electric discharge machine configured as described above, when the ram is moved in parallel during electric discharge machining, the ram itself is tilted in a direction that cancels the tilt generated in the machining head, and the ram itself is inclined by the weight of the machining head. Due to the inclination from the vertical and the inclination provided in the opposite direction in advance, it is possible to cancel the inclination generated in the processing head by a method that does not increase the weight without using the reinforcing plate.

Further, the guide rail is provided so as to incline upward from the reference position where the spatial distance from the electrode is the shortest toward the position where the spatial distance is the longest. The inclination from the vertical due to the above and the inclination of the ram horizontal portion set in advance via the guide rail cancel each other out so that the electrode can always be oriented in the vertical direction.

Furthermore, since the guide rail is inclined upward by the curve forming means for pulling up the end of the guide rail on the side where the spatial distance between the guide rail and the electrode is the longest, the inclination of the guide rail is increased. It can be formed arbitrarily, and it is not necessary to pre-tilt the guide rail.

Furthermore, the curve forming means detects the movement amount of the machining head along the guide rail, and the guide rail end portion is moved upward according to the movement amount detected by the movement amount detecting means. The guide rail can be formed on the guide rail according to the amount of movement of the machining head without the need for the operator to perform the work.

In addition, the upward inclination of the guide rail is such that the guide rail end on the side where the spatial distance between the guide rail and the electrode becomes the longest by the upward inclination provided in advance on the guide rail and the curvature adjusting means. Since it is composed of an adjustment tilt that occurs when the part is pulled up, the tilt can be adjusted reliably for any guide rail with any tilt, and the tilt of the electrode can be corrected. You can

Further, according to the movement amount of the machining head along the guide rail, the counter weight relatively moves in a direction opposite to the movement direction of the machining head and gives a moment corresponding to the movement amount to the machining head. Since we set up
Different tilts caused by the movement amount of the ram can be corrected by the moment force that changes according to the movement amount of the processing head.

[0019]

【Example】

Example 1. FIG. 1 is a configuration diagram showing a configuration of an electric discharge machine according to an embodiment of the present invention. FIG. 1 (a) shows a state when the ram 1 is not overhung, and FIG. 1 (b) is a ram. 1 shows the state when 1 overhangs. In the figure, 1 to 4 and 6 to 10 are the same as the above-mentioned conventional device, and the description thereof is omitted. Reference numeral 1c denotes a ram horizontal portion, and the machining dimension thereof is a curved mounting portion 12 which is inclined upward by an amount equal to the amount by which the machining head 2 is inclined so that the ram vertical portion 1a becomes vertical when overhung. Has been done. Reference numeral 5A denotes a Y-axis direction guide rail for moving the saddle 3 in the Y-axis direction. The curved mounting portion 12 of the ram horizontal portion 1c has a curved side portion (upward by an amount equal to the amount by which the machining head 2 tilts). Is formed). (See Fig. 1)

The ram moving type electric discharge machine has a ram vertical portion 1a.
Height of 660mm, ram horizontal part 1c length is 760m
m, the weight of the processing head 2 is 200 kg, and the processing head 2 has a maximum of 250 mm in the Y-axis direction and a maximum of 15 in the X-axis direction.
When it is possible to move by 0 mm and perform electric discharge machining,
The horizontal axis indicates the displacement amount of the ram 1 in the Y-axis direction (mm),
The vertical axis indicates the inclination of the ram vertical portion 1a from the vertical (deflection angle θ)
Thus, in the conventional device that is not reinforced by the reinforcing plate 11, as shown by the broken line A, the relationship between the displacement amount (mm) in the Y-axis direction and the angle of the inclination θ from the vertical is a finite element. It appears as a substantially straight line by the deformation analysis by the method. The increase of the inclination θ from the vertical with the increase of the displacement amount, which is shown by the broken line A in FIG. 2, is caused by the movement amount of the ram 1 in the Y-axis direction. Appears, and the processing accuracy is reduced.

On the other hand, in the ram movement type electric discharge machine shown in this embodiment, the reinforcing plate 11 is not used and the broken line A is used.
Of the ram 1 in advance in order to cancel the inclination θ when the ram vertical portion 1a moves L in the Y-axis direction as shown in FIG. A curved mounting portion 12 having an inclination θ is provided in the ram horizontal portion 1c so as to incline the entire ram 1 by −θ when it is moved L along the rail 5A in the Y axis direction. It is installed. Here, the inclination θ changes according to the movement amount L and is not necessarily constant.

Next, as shown in FIG. 3, the movement amount L of the ram 1 and the inclination θ of the ram vertical portion 1a which changes according to the movement amount L.
Using the curved mounting portion 1 provided on the ram horizontal portion 1c
Define a slope of 2. In order to cancel the inclination θ of the ram vertical portion 1a which changes depending on the movement amount L of the ram 1, if the ram vertical portion 1a is set in advance so as to be −θ when L is moved in the Y-axis direction, as a result, , The inclination of θ and the inclination of −θ cancel each other without being caught by the amount of movement L in the Y-axis direction, and the inclination of the ram vertical portion 1a from the vertical is always zero.

Actually, the machining size of the ram horizontal portion 1c to which the Y-axis direction guide rail 5A is attached is such that the height H (curved state of curved surface: curvature) from the horizontal plane of the ram horizontal portion 1c to which the Y-axis direction guide rail 5A is attached. It is processed so as to become the mounting portion 12). This height H changes with the moving distance L, and when this height H is formulated, H = Ltan θ H: height of the ram horizontal portion 1c from the horizontal plane (bending condition of the curved mounting portion 12) L: ram The movement amount of 1 is θ: can be defined as the inclination of the ram vertical portion 1a from the vertical.

FIG. 4 shows the ram vertical portion 1 shown in this embodiment.
The height of a is 660 mm, and the length of the ram horizontal portion 1c is 760 mm.
mm, the weight of the processing head 2 is 200 kg, the processing head 2
Is up to 250 mm in the Y-axis direction and up to 150 m in the X-axis direction
The approximate value of the height H in the ram movement type electric discharge machine which can be moved by m is shown. As shown in FIG. 4, the height H in the present embodiment is such that the inclination θ from the vertical increases with an increase in the displacement amount of the ram 1 (see FIG. 2) and H = Ltan θ.
The ram horizontal portion 1c is processed so that the height H becomes that value, which is obtained from the relationship represented by the equation. In fact, Ram 1
The height H from the horizontal plane is set to 3.3 μm when the object moves 125 mm in the Y-axis direction, and the height H from the horizontal surface is 13 μm when the maximum movement amount is 250 mm.
It is processed into a curved surface so as to be m.

By processing in this way, the ram 1 has 25
When moved forward by 0 mm, that is, the saddle 5 is attached to the curved mounting portion 12 in the Y-axis direction guide rail 5A.
When it reaches the curved surface of the ram 1, since the ram 1 is directed upward (inclined by −θ), the forward inclination (θ) due to the overhang of the ram vertical portion 1a is offset by each other, and the inclination of the ram vertical portion 1a uses the reinforcing plate 11. Is easily corrected (see solid line B in FIG. 2).

In general, in order to prevent the machining accuracy of the workpiece 10 from being affected by the distance between the electrode 9 and the workpiece 10, the deflection angle, which is the inclination from the vertical, is set to the maximum. It should be 0.001 ° or less. The deflection angle in the ram movement type electric discharge machine configured as in this embodiment is as shown by the solid line B in FIG. 2 by the deformation analysis by the finite element method, and is less than 0.001 ° at the maximum, and the displacement of the overhang is large. It becomes almost constant regardless of the amount (movement amount of the ram 1). In the present embodiment, an example in which the curved mounting portion 12 is processed on the ram horizontal portion 1c for mounting the Y-axis direction guide rail 5A is described. However, the surface of the Y-axis direction guide rail 5A that contacts the saddle 3 is processed. Needless to say, the same effect can be obtained by forming similar curved surfaces.

Example 2. FIG. 5 is a configuration diagram showing an example in which the curved mounting portion 12 of the ram horizontal portion 1c shown in the above-described first embodiment is configured to be capable of fine angle adjustment.
5A shows the state when the ram 1 is not overhung, and FIG. 5B shows the state when the ram 1 is overhung. In the figure, 1 to 12 are the same as those in the above-described first embodiment, and therefore description thereof will be omitted. Reference numeral 13 is a support portion fixed to the ram horizontal portion 1c by, for example, four bolts, and 14 is an external force adjusting device 1 having one end attached to the support portion 13 and the other end fixed to the ram horizontal portion 1c.
5 is a coil spring attached to 5 for generating an external force, which has elasticity higher than the rigidity of the ram horizontal portion 1c by the support portion 13, the coil spring 14 and the external force adjusting device 15, and is provided in advance upward. Y with a tilt
A bend adjusting means for pulling up the guide rail end portion on the side where the spatial distance between the axial guide rail 5A and the electrode 9 is the longest is configured.

FIG. 6 shows the supporting portion 13 and the coil spring 1.
4 and the external force adjusting device 15 are detailed configuration diagrams, and FIG. 6A is a side view seen from the X-axis direction.
6B is a top view, and FIG. 6C is a side view seen from the Y-axis direction. As shown in the figure, the external force adjusting device 15 is an end portion 15a which is an end portion of a guide rail to which one end of the coil spring 13 is attached, and by the two screws 15b penetrating, only the Y-axis direction is provided. You can move around freely. Reference numeral 15c is a fixing device that fixes the screws 15b so as to be parallel to the Y-axis direction, and is fixed to the ram horizontal portion 1c by, for example, bolts. Reference numeral 15d is a hexagon nut that is passed through two of each of the screws 15b. By changing the position of the hexagon nut 15d on the screw 15b with a wrench or the like,
The position of the end portion 15a, that is, the mounting position of the coil spring 13 is changed.

Next, the operation will be described. In the ram movement type electric discharge machine configured as described above, for example, by changing the position of the hexagon nut 15d and moving the end 15a to a position away from the support 13 (rightward in the figure), the coil The spring 14 gradually extends and generates a spring force. Here, it is necessary to use the coil spring 14 having a large spring constant, that is, one having a spring force capable of overcoming the rigidity of the ram horizontal portion 1c and deforming the ram horizontal portion 1c. The operator changes the position of the end portion 15a or changes the spring constant of the coil spring 14 to generate a spring force according to the change of the end portion 15a, whereby the curved mounting portion of the ram horizontal portion 1c is bent. The degree of curvature of 12 (corresponding to the adjustment inclination) can be adjusted. Also, the screw 15b
The reason why the two rams are used is to prevent the ram horizontal portion 1c and the Y-axis direction guide rail 5A from being deformed unevenly.

According to the present embodiment, by the adjusting mechanism of the curved portion of the ram horizontal portion 1c of the external force adjusting device 15 described above, the curvature attached in advance to the curved mounting portion 12 can be further adjusted, for example. Since it is also possible to make adjustments, the processing accuracy of the curved mounting portion provided in the ram horizontal portion 1c is reduced in advance, and fine adjustment is performed by the external force adjusting device 15 to make the inclination θ of the ram vertical portion 1a from the vertical direction θ. You can also deal with. Further, it is possible to correct a fine deviation that may occur due to variations in the installation state of the ram movement type electric discharge machine itself.

Here, as the adjustment inclination, the curved mounting portion 1
When it is necessary to further adjust the curve of No. 2 by ζ (ζ + θ = θ1), ζ = Ltan θ1 ζ: the height at which the curve mounting portion 12 needs to be adjusted L: the amount of movement of the ram 1, as in the first embodiment θ1: It can be defined as the inclination of the ram vertical portion 1a from the vertical. In addition, if there is a tilt θ1 of 0.001 ° or more from the vertical of the ram vertical portion 1a that cannot be corrected by only the method of the first embodiment, it may be corrected.

Further, in this embodiment, the coil spring 1
4 and the function of the external force adjusting device 15, the curved mounting portion 1
Although the description has been made by taking the case of performing the adjustment of 2 as an example, it is needless to say that any one may be used as long as it has an external force that deforms the ram horizontal portion 1c, for example, an external force generating mechanism by a magnetic force or the like. ,

Further, although the embodiment in which the bending adjusting means is constituted by the supporting portion 13, the coil spring 14 and the external force adjusting device 15 has been described, the bending forming means for pulling up the end portion 15a corresponding to the end portion of the guide rail is raised. Similarly, if the support portion 13, the coil spring 14 and the external force adjusting device 15 are similarly configured, the ram horizontal portion 1 can be obtained by pulling up the end portion 15a corresponding to the guide rail end portion.
cY-axis direction guide rail 5 installed parallel to the bottom surface
It is also possible to give A an inclination equal to the inclination from the vertical that occurs in the processing head. According to this structure, when the coil spring 14 is selected so that the spring constant overcomes the rigidity of the ram horizontal portion 1c and can be performed by the ram horizontal portion 1c, the ram horizontal portion 1c is set in advance and the mounting portion 1 is attached.
It is not necessary to provide 2, and the ram horizontal portion 1c is changed later by changing the position of the end portion 1 vertically with the hexagon nut 15d.
It is possible to accurately provide a curved line (a phase portion to the curved mounting portion 12), which facilitates the design and processing of the ram horizontal portion 1c. At this time, it goes without saying that the Y-axis direction guide rail 5A automatically inclines upward.

Example 3. Further, in the above-described first embodiment, an example in which the curved mounting portion 12 is provided in advance on the ram horizontal portion 1c is shown, but by using the technical idea shown in the second embodiment, as shown in this embodiment. In addition, the coil spring 14 whose spring constant overcomes the rigidity of the ram horizontal portion 1c and can deform the ram horizontal portion 1c is selected.
The curved mounting portion 12 is formed on the ram horizontal portion 1c according to the amount of movement of the overhang in the Y-axis direction, and the degree of inclination of the curved mounting portion 12 may be automatically changed according to the amount of movement in the Y-axis direction. it can. FIG. 7 is a configuration diagram showing the configuration of the present embodiment. In the figure, 1 to 14 are the same as those in the above-described embodiment, and therefore description thereof will be omitted. Reference numeral 16 is a motor-driven external force adjusting device corresponding to the external force adjusting device 15 in the second embodiment, and based on the displacement amount of the ram 1 in the Y-axis direction.
End 16 to which one end of the coil spring 14 is attached
a is displaced in the Y-axis direction, and the spring mounting force (elastic restoring force) of the coil spring 14 deforms the curved mounting portion 12 of the ram horizontal portion 1c.

Next, the function of the motor-driven external force adjusting device 16 with respect to the ram horizontal portion 1c will be described in detail below. Figure 7
As shown in (a), when the ram 1 is not overhung, the end portion 1 of the motor-driven external force adjusting device 16 is
6a is in a state of being closest to the support portion 13,
The spring force (elastic restoring force) of the coil spring 14 does not act on the ram horizontal portion 1c, and of course, the Y-axis direction guide rail 5A provided on the ram horizontal portion 1c is tilted horizontally with respect to the saddle 3. There is no state. However, as shown in FIG. 7 (b), the ram 1 becomes Y by the electric discharge machining.
When the motor-driven external force adjusting device 16 overhangs in the axial direction by the displacement amount L, the motor-driven external force adjusting device 16 calculates the displacement amount L in the Y-axis direction, and the inclination from the vertical with the displacement amount L (deflection angle: see FIG. 2). In order to tilt the ram vertical portion 1a in advance in order to cancel the above, the end portion 16a is moved in the direction opposite to the Y-axis direction in which the ram 1 is displaced.

By moving the end portion 16a in the direction opposite to the displacement direction of the ram 1, the coil spring 14 is extended in the Y-axis direction and a spring force (elastic restoring force) is generated.
Due to this spring force (elastic restoring force), when considering the rigidity of the support portion 13 and the ram horizontal portion 1c, if the rigidity of the ram horizontal portion 1c is smaller, the ram horizontal portion 1c loses the spring force, and Curved mounting portion 12 having a curvature equal to the inclination
Is formed. The bending of the curved mounting portion 12 depends on the spring constant of the coil spring 14 and the movement amount of the end portion 16a. When the ram 1 moves the displacement amount L in the Y-axis direction,
Since the displacement amount of the curved mounting portion 12 to be curved forward of the ram 1 can be obtained in advance (see FIG. 4), the end portion 16a is set to the moving direction of the ram 1 in the Y-axis direction by the spring constant of the coil spring 14. Can be calculated in advance how much to move in the opposite direction, and based on the pre-calculated movement amount result of the end portion 16a, the end of the ram 1 can be calculated in accordance with the displacement amount L in the Y-axis direction. The portion 16a is automatically moved by a motor or the like.

As in this embodiment, the displacement amount L of the ram 1 is set in advance.
The inclination (deflection angle) from the vertical due to this is calculated, and the spring constant of the coil spring 14 and the bending degree of the bending attachment portion 12 that is generated with the movement amount of the end portion 16a of the motor-driven external force adjusting device 16 are calculated in advance. Based on the calculation result, the displacement amount L of the ram 1 in the Y-axis direction
The end portion 16a can be automatically moved to cancel the inclination from the vertical. Here, since it is not necessary to previously provide the curved mounting portion 12 on the ram horizontal portion 1c, the ram 1 can be easily designed and processed. Further, since the motor-driven external force adjusting device 16 controls the spring force (elastic restoring force) of the coil spring 14 based on the value stored in advance, the operator does not need to make fine adjustments himself, and the workability is improved. .

Example 4. In the above-described embodiment, the ram horizontal portion 1c is provided with the curved mounting portion 12 that is a curve corresponding to the inclination (deflection angle) from the vertical, and thus the inclination is canceled, but in the present embodiment, In addition to the above-described embodiment, relative to the amount of movement of the ram 1 along the Y-axis direction guide rail 5A, which penetrates the balance bar 17 fixed to the ram vertical part 1a so as to be parallel to the ram horizontal part 1c, The electrode 9 in the opposite direction to the moving direction of the electrode 9,
With respect to the ram vertical portion 1a, the inclination from the vertical is corrected by the weight 18, which is a counter weight that gives a moment according to the moving amount. 8A and 8B are configuration diagrams showing the configuration of the present embodiment. FIG. 8A shows a state when the ram 1 is not overhung, and FIG. 8B is a state where the ram 1 is overhung. It shows the state when it is. Further, FIG. 8C is a view of the ram movement type electric discharge machine seen from the Y-axis direction.

In the figure, 1 to 10 are the same as those in the above-mentioned embodiment, and the explanation thereof is omitted. Reference numeral 17 is a balance bar, one end of which is a stopper 18 and the other end of which is vertically fixed to the ram vertical portion 1a by bolts or the like.
The stopper 18 is screwed and fixed to the balance bar 17 so that it can be removed. , 19 are weights, and the balance bar 17 penetrates through a through hole provided in the center thereof to move, but a stopper 18 prevents the weight from falling off. Reference numeral 20 denotes a weight moving auxiliary device that horizontally moves the weight 19 when the ram 1 moves back and forth, and the ram horizontal portion 1c has a maximum of 150 m in the X-axis direction.
Since the ram 1 is moved by m, even if the ram 1 is moved by the maximum displacement in the X-axis direction, the weight 19 is elongated in the left-right direction so that the weight 19 can be moved. However, it does not support the weight of the weight 19, and is attached via a spring 22 at one end of a holding rod 21 that is bolted to the side of the column 6.

Since the weight moving auxiliary device 20 has the spring 22 interposed therebetween, the weight 19 does not hinder the movement of the ram 1 even if the ram 1 freely moves in the X axis direction and the Y axis direction. Can be moved. Further, the holding rod 21 is bent in the middle, and is designed so that the holding rod 21 and the ram horizontal portion 1c do not interfere with each other even if the ram horizontal portion 1c is displaced to the maximum in the X-axis direction. . (See FIG. 8C) Furthermore, the rigidity of the spring 22 needs to be high so that the weight 19 can move when the ram 1 moves.

Next, the operation will be described with reference to FIG. In the ram movement type electric discharge machine configured as described above, the ram 1 as shown in FIG. 8 (b) is changed to Y from the state in which the ram 1 is not overhung as shown in FIG. 8 (a). An overhang in the axial direction usually causes a tilt (deflection angle) θ from the vertical. Therefore, the curved mounting portion 12 is provided in order to cancel the inclination θ from the vertical in the first to third embodiments described above. However, if the inclination θ from the vertical is not completely offset by the curved mounting portion 12, the weight 19 penetrated by the through hole in the balance rod 18 is not completely offset by the ram vertical portion 1 as shown in this embodiment.
The ram vertical portion 1a is deformed and balanced by a variable force by relatively moving from a position close to a to a position apart in the Y-axis direction, and the curved mounting portion 12 cancels the inclination (deflection angle) from the vertical. If not performed, it functions to offset the tilt (deflection angle) θ2 that has not been offset.

More specifically, when a tilt (deflection angle) θ2 (0.001 or more) that has not been offset is generated, the tilt θ2 is from the vertical direction of the machining head 2 which affects machining accuracy. Since it exceeds the allowable range of the inclination of
It becomes necessary to correct the inclination θ2. As shown in FIG. 8A, when the overhang of the processing head 2 is small, the position of the weight 19 is small in relative movement due to being brought into contact with the weight movement auxiliary device 20,
It exists near the ram vertical portion 1a. Therefore, the moment M1 acting on the ram vertical portion 1a is small, and the ram vertical portion 1a
Is not deformed. As shown in FIG. 8 (b),
When the overhang of the processing head 2 increases, the position of the weight 19 is brought into contact with the weight moving auxiliary device 20 and relatively moved by the past head 2 from the ram vertical portion 1a by the moving amount of the overhang. Lamb vertical section 1a
Get away from. Therefore, the moment M2 acting on the ram vertical portion 1a becomes large, and as a result, the ram vertical portion 1a
Can be prevented from tilting from the vertical due to its own weight, and the processing accuracy can be further improved.

FIG. 9 shows the inclination θ of the machining head 2 from the vertical.
The moment required to correct 2 is obtained by the finite element method. In the figure, when the horizontal axis is the inclination θ2 (°) from the vertical and the vertical axis is the moment (kg · mm) required to correct the inclination θ2, it is expressed as shown in FIG. From the relationship with the moment required for correction, m = (θ2-0.001) × 10000 m: size of the weight 19 (kg) θ2: inclination of the machining head 2 from the vertical can be obtained.

In the present embodiment, the inclination θ2 when the ram 1 is moved in the Y-axis direction of 250 mm is 0.0015 °. Therefore, considering the processing accuracy, it is necessary to correct the inclination of at least 0.0005 °. . The weight 19 is determined to be 5 kg from m = (0.0015−0.0010) × 10000 in order to correct at least 0.0005 ° of the inclination θ2 of the ram vertical portion 1a from the vertical.

In other words, by providing the weight 19 of 5 kg, the processing accuracy can be improved by the synergistic effect with the first embodiment, for example. The weight 19 is the stopper 1
By removing 8, the weight can be removed from the balance bar 17 and the weight can be changed, the magnitude of the moment acting on the ram vertical portion 1a can be finely adjusted, and fine correction for coping with any inclination is possible. In the above-described embodiment, the method of coping with the tilt in the Y-axis direction is shown.
It goes without saying that the same effect can be obtained by similarly configuring the inclination in the X-axis direction.

[0046]

Since the present invention is constructed as described above, it has the following effects. A ram having a machining head supporting an electrode facing a workpiece, a ram vertical portion on which the machining head is mounted, and a ram horizontal portion vertically extending the ram vertical portion; Guide means for processing the workpiece placed in the processing tank into an arbitrary shape by means of and tilting means for tilting the ram in a direction that cancels the tilt generated in the processing head during parallel movement of the ram. Since the inclination of the bending portion cancels the inclination of the machining head from the vertical, the inclination due to the overhang of the ram can be corrected without using the reinforcing plate. Therefore, high-precision electric discharge machining becomes possible.

Further, a machining head supporting an electrode for machining a workpiece, a ram vertical portion on which the machining head is mounted,
And a ram having a ram horizontal portion that vertically extends the ram vertical portion so as to face the workpiece placed in the processing tank, and the ram is fixed to the lower surface of the ram horizontal portion, and the electrode From a reference position having the shortest spatial distance to a position having the longest spatial distance, and a guide rail that gradually inclines upward, and a guide rail guide portion that guides the ram in the longitudinal direction of the guide rail. Therefore, according to the movement of the horizontal part of the ram, the machining head is inclined by the amount of the inclination provided on the guide rail, and the inclination is offset by the inclination from the vertical depending on the movement amount of the machining head. The tilt due to overhang of the ram can be corrected without using.

Further, since the upward inclination of the guide rail is formed by the curve forming means for pulling up the end portion of the guide rail on the side where the spatial distance between the guide rail and the electrode is longest, the guide rail is inclined with respect to the guide rail. It is not necessary to preset an accurate inclination for canceling the inclination of the electrode, and the guide rail can be easily formed.

Further, the curve forming means detects the movement amount detecting means for detecting the movement amount of the machining head along the guide rail, and the guide rail end portion according to the movement amount detected by the movement amount detecting means. Since the forming means for pulling upward and forming the upward inclination is provided, it is possible to automatically adjust the inclination of the machining head from the vertical according to the moving amount of the ram.

Furthermore, the upward inclination of the guide rails is provided in advance on the guide rails and the guide on the side where the spatial distance between the guide rails and the electrode is the longest by the curve adjusting means. Since the adjustment inclination is generated when pulling up the rail end portion upward, even if the processing accuracy of the upward inclination set in advance on the guide rail is poor, the bending adjustment means can adjust the inclination of the guide rail. The guide rail can be adjusted, and the guide rail is not required to be accurately machined from the beginning, and the workability of forming the guide rail is improved. Further, since the bending adjustment means can adjust a portion where the machining accuracy is low, a highly accurate inclination can be obtained after the guide rail is mounted on the ram, and the inclination of the machining head from the vertical can be reliably corrected. be able to.

In addition, a counter weight that relatively moves in the direction opposite to the moving direction of the electrode according to the moving amount of the machining head along the guide rail and gives a moment corresponding to the moving amount to the electrode is provided. Since it is provided, the counterweight moves away from the machining head relative to the amount of movement of the ram, and the moment based on the relative distance from the machining head ensures the automatic tilt of the machining head from the vertical. It can be corrected and workability is improved.

[Brief description of drawings]

FIG. 1 is a structural diagram of an electric discharge machine showing an embodiment of the present invention.

FIG. 2 is a relationship diagram showing a relationship between a displacement amount of a ram and an inclination of a machining head from a vertical direction.

FIG. 3 is a structural diagram showing a detailed configuration of a curved mounting portion.

FIG. 4 is a relationship diagram showing a relationship between a displacement amount of a ram and a height of a curved mounting portion.

FIG. 5 is a structural diagram of an electric discharge machine showing another embodiment of the present invention.

FIG. 6 is a detailed view showing a detailed configuration of a support portion, a coil spring, and an external force adjusting device.

FIG. 7 is a structural diagram of an electric discharge machine showing another embodiment of the present invention.

FIG. 8 is a structural diagram of an electric discharge machine showing another embodiment of the present invention.

FIG. 9 is a relationship diagram showing a relationship between a tilt of the processing head from the vertical and a moment required to correct the tilt.

FIG. 10 is a configuration diagram showing a configuration of a conventional electric discharge machine.

FIG. 11 is a configuration diagram showing a configuration in which a reinforcing plate is added to a conventional electric discharge machine.

[Explanation of symbols]

1 Ram 1a Ram Vertical Part 1c Ram Horizontal Part 2 Processing Head 8 Processing Tank 9 Electrode 10 Workpiece 12 Curved Mounting Part 13 Supporting Part 14 Coil Spring 15 External Force Adjusting Device 16 Motor Driven External Force Adjusting Device 17 Balance Bar 19 Weight

Claims (6)

[Claims] 1. A ram having a machining head that supports an electrode facing a workpiece, a ram vertical portion on which the machining head is mounted, and a ram horizontal portion that vertically extends the ram vertical portion; A guide means for moving the workpiece in a desired shape, which is moved in parallel by the electrode and arranged in the processing tank, and a direction in which the inclination generated in the processing head during the parallel movement of the ram is offset. An electric discharge machine comprising: an inclining means for inclining a ram. 2. A machining head supporting an electrode for machining a work piece, a ram vertical portion mounted with the machining head, and the electrode so as to face the work piece arranged in a machining tank. A ram having a ram horizontal portion vertically extending a ram vertical portion, and a ram fixed to the lower surface of the ram horizontal portion of the ram from a reference position where the spatial distance from the electrode is the shortest to a position where the spatial distance is the longest. An electric discharge machine comprising: a guide rail that gradually inclines upward as it goes, and a guide rail guide portion that guides the ram in the longitudinal direction of the guide rail. 3. The upward inclination of the guide rail is formed by a curving forming means for pulling up an end portion of the guide rail on the side where the spatial distance between the guide rail and the electrode is the longest. The electric discharge machine according to claim 2. 4. The curve forming means includes a movement amount detecting means for detecting a movement amount of the processing head along the guide rail, and a guide rail end portion according to the movement amount detected by the movement amount detecting means. The electric discharge machine according to claim 3, further comprising a forming unit that pulls upward and forms an upward inclination. 5. The upward inclination of the guide rail is provided on the guide rail in advance, and the guide rail on the side where the spatial distance between the guide rail and the electrode is the longest by the curvature adjusting means. The electric discharge machine according to claim 2, wherein the electric discharge machine comprises an adjustment inclination generated when the end portion is pulled upward. 6. The machining head moves relatively in a direction opposite to the moving direction of the machining head according to the movement amount of the machining head along the guide rail, and a moment corresponding to the movement amount is applied to the machining head. The electric discharge machine according to any one of claims 2 to 5, wherein a counter weight to be given is added.