JP2007136465A - Press machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a press machine in which the local wear between a ball and a ball groove can be prevented, and the undesired rotation of a nut supporting member can be suppressed, and which can withstand strong pressing force caused in a press working. <P>SOLUTION: In the motor-driven press machine, a rotation lock means of suppressing the rotation in a nut supporting member is provided, and, the connection between a differential member and a slider is made into the relation of screw bonding, and then, the displacement of the height position of the slider to the rotation of the differential member is made fine. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a press apparatus used for, for example, sheet metal processing and the like, and more particularly to a press apparatus capable of fixed point processing requiring accurate position control.

  Conventionally, as a means for driving a ram that abuts against a workpiece in a press working apparatus, a fluid pressure cylinder has been widely used, and in particular, a hydraulic cylinder has been frequently used. In the press device driven by the hydraulic cylinder, when performing fixed point processing, that is, processing in a state in which the distance between the ram and the table is kept constant, it is necessary to perform processing commonly referred to as “barrel thrust processing”.

  As an alternative to the press device driven by the hydraulic cylinder described above, an electric press method in which a screw shaft is rotated with respect to a nut member by an electric motor to move a slider up and down is being adopted.

  According to such an electric press, fixed point machining can be performed without generating noise, but there are the following problems. That is, the height h from the table on the lower end surface of the pressing body is controlled so as to be always constant because of fixed point machining, and a predetermined pressing force is applied to the workpiece through the pressing body at this position. Will be applied. In other words, the reaction force corresponding to the pressing force is always applied to the screw shaft and the nut body at the same relative position, and the same is applied to the screw shaft, the nut member, and the ball interposed between them. Repeated force is applied to the location, and the screw shaft, nut member and ball are undesirably scratched.

  The applicant of the present application has filed a patent application (Patent Document 1) that has taken measures to solve the above-described problems in the electric press, and has become a patent.

  FIG. 3 is a front view of a main part longitudinal section showing the form of the press device disclosed in Patent Document 1, and FIG. 4 is a cross-sectional plan view of the main part of FIG. In both figures, 1 is a board | substrate, for example, is formed in rectangular flat plate shape, for example, the cylindrical guide bar 2 is standingly arranged in the four corners. A support plate 3 formed in, for example, a rectangular flat plate shape is fixed to the upper end portion of the guide bar 2 via, for example, a fastening member 4.

  Next, reference numeral 5 denotes a screw shaft, which is supported at the center of the support plate 3 through the bearing member 6 so as to pass through the support plate 3 so as to be able to rotate forward and backward. A movable body 7 is engaged with the guide bar 2 so as to be movable in the axial direction thereof. A nut member 8 is formed by integrally connecting a nut portion 10 having a flange portion 9 and a cylindrical portion 11 formed in a hollow cylindrical shape. The nut portion 10 is screwed with the screw shaft 5 by ball screw engagement, and a differential male screw 13 is provided on the outer peripheral surface of the cylindrical portion 11.

  Reference numeral 14 denotes a differential member, which is formed in a hollow cylindrical shape, and is provided with a differential female screw 15 that is screwed into the differential male screw 13 on the inner peripheral surface. Reference numeral 16 denotes a worm wheel that is integrally fixed to the differential member 14 and is formed to engage with the worm 17. Reference numerals 18 and 19 denote radial bearings and thrust bearings, which are provided in the movable body 7 and support the differential member 14 and the worm wheel 16, respectively.

  Reference numeral 20 denotes a worm shaft that is inserted into and fixed to the central portion of the worm 17 and is rotatably supported by bearings 21 and 21 provided in the movable body 7 at both ends. Reference numerals 22 and 23 denote pulse motors, respectively, which are provided so that the screw shaft 5 and the worm shaft 20 can be rotated. Reference numeral 24 denotes a presser, which is detachably provided on the lower surface of the central portion of the movable body 7. The pulse motors 22 and 23 are configured to be controlled and driven by applying predetermined pulses via a control device (not shown).

With the above configuration, when the pulse motor 22 is operated by applying a predetermined number of pulses, the screw shaft 5 rotates, the movable body 7 including the nut member 8 is lowered, and the pressing element 24 has an initial height H _0. Is lowered to a fixed point machining height H and comes into contact with the workpiece W. As a result, fixed-point machining is performed on the workpiece W with a pressing force set in advance via the pressing element 24. After machining end, the movable member 7 is raised by the reverse operation of the pulse motor 22, the presser 24 returns to the position of the initial height H _0. Note that the values of H ₀ and H are measured by measurement means (not shown) and can be controlled in relation to the pulse motor 22.

When the above-mentioned fixed point machining reaches a preset number of times, the operation of the pulse motor 22 is stopped at the position shown in FIG. 3, that is, the position of the initial height H ₀ of the presser 24, and the pulse motor 23 is preset. Apply the number of pulses. As a result, the pulse motor 23 rotates by a predetermined number, and the differential member 14 rotates by a predetermined center angle via the worm shaft 20, the worm 17 and the worm wheel 16. As the differential member 14 is rotated, the nut member 8 is stopped and locked, that is, the differential female screw 15 is rotated with respect to the stopped differential male screw 13. Displace.

The initial height H ₀ of the pressing element 24 naturally changes due to the displacement of the movable body 7. Therefore, when the screw shaft 5 is rotated as it is, a predetermined fixed point machining cannot be performed. For this reason, next, a slight number of pulses controlled by the pulse motor 22 is applied to slightly rotate the screw shaft 5 to cancel the displacement of the movable body 7 and the pressing element 24, and the initial height of the pressing element 24 is increased. An operation is performed to keep the height H ₀ constant.

The relative position between the screw shaft 5 and the nut portion 10 is changed by the rotation of the screw shaft 5 described above. That is, the relative position between the ball and the ball groove formed in the ball screw engagement can be changed, and the local wear of the ball and / or the ball groove can be prevented while securing the fixed point processing. After performing the correction operation as described above, the fixed point machining is continued again.
JP 2000-218395 A

  In the press apparatus disclosed in Patent Document 1, the operation by the motor 23 and then by the motor 22 are performed after one processing of fixed point processing or after a plurality of predetermined times (for example, 10 times) processing. Thus, the relative position between the screw shaft 5 and the nut portion 10 and on the ball can be changed.

However, the following problem newly occurred while operating the press apparatus disclosed in Patent Document 1. That is,
(A) The differential member 14 is rotated by the motor 23 via the worm 17 and the worm wheel 16, and at this time, the female screw 15 existing on the inner peripheral surface of the differential member 14 is placed on the outer peripheral surface of the nut member 8. Since the external thread 13 is screwed and the nut member 8 is screwed with the screw shaft 5 and is fixed to the support plate 3 in a non-rotating state, the movable body 7 is consequently formed. It is supposed to move slightly in the vertical direction with respect to the support plate 3 (in other words, with respect to the substrate 1).

  However, although the friction between the screw shaft 5 and the nut member 8 (friction through the ball) is relatively large in the initial stage of operation, there is no problem. It has been found that the friction becomes small, and even the nut member 8 is slightly rotated with respect to the support plate 3 in response to the rotation of the differential member 14.

  If this minute rotation occurs undesirably and irregularly, as described above, the result of rotating the differential member 14 by the motor 23 is corrected by the motor 22, but the canceling operation cannot be performed properly. That is, it has been found that fixed point machining cannot be performed correctly.

(B) The differential member 14 is supported in the vertical direction by the bearings 18 and 18 with respect to the movable body 7. That is, when fixed point machining is performed, when the differential member 14 is moved downward together with the nut member 8 by the motor 22 to perform a pressing operation, the bearing 18 is moved from the movable body 7 side. You will receive a strong reaction force.
For this reason, it has been found that the bearing 18 is worn out.

  In order to solve the above-described problem, the present invention suppresses undesired rotation of a member corresponding to the nut member 8 in Patent Document 1 and uses a means in place of the bearing 18 in Patent Document 1. It is an object.

For this purpose, the press device of the present invention is provided with a substrate, a guide bar provided so that one end thereof is orthogonal to the substrate, and a guide bar provided at the other end of the guide bar. A support plate, a screw shaft supported by the support plate so as to be rotatable forward and backward, a slider engaged with the guide bar so as to be movable in the axial direction of the guide bar, and a hollow shape. A nut support member having a first differential screw on the outer peripheral surface and formed so as to be screwed with the screw shaft, and formed in a hollow shape and screwed with the first differential screw on the inner peripheral surface. In a press device having a differential member that has a second differential screw and is formed to be rotatable with respect to the slider, and a drive member that rotationally drives the differential member.
A third screw including a zero pitch is provided on the outer peripheral surface of the differential member,
A fourth screw including a zero-pitch portion, which is placed on and fixed to the slider and is screwed with the third screw, is provided;
And provided with a rotation lock means placed on the slider to inhibit the rotation of the nut support member relative to the slider,
The pitches of the first differential screw and the second differential screw are different from each other with respect to the pitch of the third screw and the fourth screw.

  In the press apparatus of the present invention, the screw shaft and / or the nut is adopted even if the electric press method is employed in which the screw shaft is rotated with respect to the nut support member by the electric motor to move the slider up and down and the fixed point machining is continued. It is possible to prevent local wear of the parts related to the parts, that is, the balls and / or the ball grooves. And the problem which arises on it, ie, it can prevent that a nut support member rotates undesirably. Further, since the differential member is connected to the slider using the third screw and the fourth screw, the connection by the bearing used in Patent Document 1 can be eliminated.

  More importantly, by performing the connection using the third screw and the fourth screw, the amount of vertical movement of the slider is reduced to, for example, 1/10 compared to the amount of vertical movement accompanying the rotation of the differential member. Thus, the position movement between the ball and the ball groove can be performed very little by little.

  As a result, the position movement between the ball and the ball groove, which is performed after a single fixed point machining or after a plurality of predetermined machinings, can be performed accurately and in minute units.

FIG. 1 is a view for explaining the configuration of the slider vertical movement portion used in the press apparatus of the present invention.
1 shows only portions corresponding to members 2, 3, 4, 5, 6, 7, 8, 10, 11, 13, 14, 15, 16, 17, 18, and 19 in Patent Document 1. The members 1 and 24 are omitted. However, only one slider vertical movement portion disclosed in FIG. 1 may be used in one press device as in the case of the press device shown in Patent Document 1, but generally one unit is used. For example, four press bars are provided at positions corresponding to four guide bars 2, and the sliders (corresponding to the movable body 7 in Patent Document 1) are driven in cooperation with each other. Has been. For this purpose, a dotted line is entered at the right end in FIG.

  In FIG. 1, reference numerals 2 to 15 and 22 correspond to FIG. 3. Among them, reference numerals 7 ′, 8 ′, 10 ′ and 11 ′ are changed from reference numerals 7, 8, 10 and 11 in FIG. 3. It is a thing of the aspect. Reference numeral 23 corresponds to FIG.

  Similar to the press apparatus shown in FIG. 3, cylindrical guide bars 2 are provided upright at four corners of a substrate (not shown). The upper end portion of the guide bar 2 is fixed to the support plate 3 via the fastening member 4.

  The screw shaft 5 is supported so as to be able to rotate forward and backward so as to penetrate the support plate 3 via the bearing member 6 with respect to the support plate 3. The slider 7 ′ is slidably engaged with the guide bar 2 via a slider sliding portion 51. The screw shaft 5 is connected to the rotation shaft of the press motor 22 by a screw shaft connecting portion 52.

  The nut support member 8 ′ is formed by integrally connecting a nut member 10 ′ and a nut moving member 11 ′ formed in a hollow cylindrical shape via a lock support plate 57 and a lock support receiving plate 58. The nut support member 8 ′ is screwed to the screw shaft 5 by ball screw engagement in the nut member 10 ′, and the first differential is attached to the outer peripheral surface of the nut movement member 11 ′ in the nut movement member 11 ′. A screw 13 is provided.

  The differential member 14 is formed in a hollow shape, has a second differential screw 15 screwed to the first differential screw 13 on the inner peripheral surface, and includes one having a zero pitch on the outer peripheral surface. A third screw 70 is provided. Then, a gear 63 that is screwed with the pinion 62 via the pinion 62 is provided, and the differential member 14 is rotationally driven around the central axis by the drive member 60.

  The drive member 60 is composed of, for example, a differential motor 23 supported by a drive member support base 64 fixedly mounted on a slider 7 ′, a speed reduction mechanism 61, and the pinion 62 described above.

  As will be described later, the differential member 14 is rotatable about the central axis as described above, but is further movable up and down in a minute range in the central axis direction. For this purpose, the gear 63 formed on the differential member 14 moves slightly in the vertical direction while being screwed to the pinion on the drive member 60 side.

  In the present invention, as described above, when the differential member 14 is rotated, the nut support member 8 ′ that should be maintained in a non-rotating state is not undesirably rotated. A rotation lock means 53 is provided.

FIG. 2 shows a main configuration of the rotation lock means.
A lock support plate 57 is fixed to the lock support receiving plate 58, and the lock support plate 57 is supported by sliding support shafts 55-1, 55-2, and 55-3 at three locations in the illustrated case. Thus, the nut support member 8 ′ is prevented from rotating undesirably. Each sliding support shaft 55-i is inserted into the sliding receiving portion 56-i, and each sliding receiving portion 56-i is fixed to the slider 7 '. The sliding support shaft 55-i and the sliding receiving portion 56-i constitute a vertical sliding portion 54-i that allows the sliding support shaft 55-i to slide in the vertical direction.

  Further, in the present invention, a fourth screw 71 including a zero-pitch portion that meshes with the third screw 70 provided on the outer peripheral surface of the differential member 14 is provided, and the fourth screw 71 is fixedly attached to the slider 7 '. It is also important in the present invention that the pitch of the first differential screw 13 and the second differential screw 15 is different from the pitch of the third screw and the fourth screw. It is configured.

  That is, the pitch between the third screw 70 and the fourth screw 71 is, for example, 14 mm / pitch, and the pitch between the first differential screw 13 and the second differential screw 15 is, for example, 12 mm / pitch.

  In such a configuration, the press motor 22 is now stopped, and therefore the screw shaft 5 is stopped and the nut support member 8 ′ is stopped with respect to the support plate 3. To do.

Under this state, it is assumed that the differential member 14 is rotated once by the drive member 60 through screwing of the pinion and the gear. That is, the second differential screw 15 existing on the inner peripheral surface of the differential member 14 is one pitch away from the first differential screw 13 existing on the outer peripheral surface of the nut moving member 11 ′ that is stopped. It is assumed that the differential member 14 has moved down by, for example, 12 mm. At this time, the third screw 70 positioned on the outer peripheral surface of the differential member 14 makes one rotation with respect to the fourth screw 71 fixed to the slider 7 ′. At this time, one rotation is performed while meshing with the fourth screw 71 fixed in a non-rotating state with respect to the slider 7 ′, but the pitch between the third screw 70 and the fourth screw 71 is 14 mm. Therefore, the fourth screw 71 is lowered by 2 mm. Furthermore, the slider 7 'is lowered by 2 mm. That is, the slider 7 'is 14mm-12mm = 2mm.
Will only descend.

In the press apparatus of the present invention having the above-described configuration, when the press motor 22 is operated for press working (the drive member 60 is stopped during the press work), the screw shaft 5 rotates. Since the nut member 10 'is screwed to the screw shaft 5 (not to mention, the nut member 10', more specifically, the nut support member 8 'is in a non-rotating state), the nut support The member 8 'descends. At this time, the nut support member 8 ′ has the first differential screw 13 and the second differential screw 15 engaged with the differential member 14 and the third screw 70 with respect to the slider 7 ′. While the fourth screw 71 is engaged, the entire screw descends in a state of non-rotating with respect to the support plate 3. That is, as in the conventional case shown in FIG. 3, the presser 24 (see FIG. 3) attached below the slider 7 ′ is lowered from the initial height H ₀ to the fixed point processing height H, and the workpiece is processed. It contacts the object W (see FIG. 3). As a result, fixed-point machining is performed on the workpiece W with a pressing force set in advance via the pressing element 24.

After the processing end, the slider 7 'is raised by reverse actuation of the press motor 22, the presser 24 returns to the position of the initial height H _0. Note that the values of H ₀ and H are measured by measurement means (not shown) and can be controlled in relation to the press motor 22.

When the above-mentioned fixed point machining reaches once or a preset number of times, that is, the press motor 22 is stopped at the initial height H ₀ of the presser 24, and the differential motor 23 is rotated by a predetermined amount. The rotation of the differential motor 23 is decelerated by the speed reduction mechanism 61 and is further decelerated by the pinion 62 and the gear 63 so that the differential member 14 is rotated by a minute amount.

As described above, the result of the rotation of the differential member 14 by the minute amount is that the slider 7 'is moved by the minute amount Δ (actually, Δ is a value of about 10 μm), and the height position of the above-mentioned H _0. For example, it will be lowered. Therefore, when the next press working is executed under this condition, the initial height is (H ₀ −Δ), and therefore, the predetermined fixed point machining cannot be performed. In order to return this (H ₀ −Δ) to the original H ₀ , the press motor 22 is slightly rotated prior to the next press work to raise the slider 7 ′ by Δ, which is necessary for fixed point machining. The initial height H ₀ is maintained. During the correction operation of Δ, the position between the nut member 10 ′ and the screw shaft 5 changes slightly, that is, the position between the ball and the ball groove changes slightly, and the next fixed point machining is performed. This means that the positional relationship between the ball and the ball groove that has occurred during the last fixed point machining is slightly changed.

  That is, as described in Patent Document 1, local wear between the ball and the ball groove can be prevented.

  In the present invention, as described in Patent Document 1, local wear between the ball and the ball groove can be prevented, and the bearing 18 (see FIG. 3) used in Patent Document 1 is pressed during press working. The third screw 70 and the fourth screw 71 support the press pressing force in place of the state where the pressing force was endured, and can withstand a stronger press pressing force.

In the present invention, the rotation lock means 53 prevents the nut support member 8 ′ from turning undesirably. When the differential member 14 is rotated by the drive member 60, and as a result, the slider 7 ′ is displaced in height by the Δ, suppose that the nut support member 8 ′ rotates undesirably. The amount of displacement of the slider 7 'is not the correct Δ but Δ'. As a result, when the press motor 22 cancels only Δ, the initial height at the next fixed point machining is (H ₀ −Δ) + Δ ′.
End up. However, in the present invention, since the rotation of the nut support member 8 ′ is suppressed by the rotation lock means 53, this problem can be solved.

  The rotation lock means prevents undesired rotation of the nut support member, and the configuration using the third screw and the fourth screw can eliminate the conventional bearing, and further, The pitches of the first differential screw and the second differential screw are different from each other with respect to the pitch of the third screw and the fourth screw. The displacement can be made extremely small.

It is a figure explaining the structure of the slider vertical movement part used for the press apparatus of this invention. It is a figure which shows the principal part structure of a rotation lock means. It is a principal part longitudinal cross-section front view which shows the form of the press apparatus disclosed by patent document 1. FIG. FIG. 4 is a cross-sectional plan view of an essential part of the AA line in FIG. 3.

Explanation of symbols

2: Guide bar 3: Support plate 4: Fastening member 5: Screw shaft 6: Bearing member 7 ': Slider 8': Nut support member 10 ': Nut member 11': Nut moving member 13: First differential screw 14 : Differential member 15: second differential screw 22: press motor 23: differential motor 51: slider sliding part 52: screw shaft coupling part 53: rotation locking means 54: vertical sliding part 55: sliding Support shaft 56: Slide receiving portion 57: Lock support plate 58: Lock support receiving plate 60: Drive member 61: Deceleration mechanism 62: Pinion 63: Gear 64: Drive member support base 70: Third screw 71: Fourth screw

Claims (4)

A substrate, a guide bar provided on the substrate so that one end thereof is orthogonal to the substrate, a support plate provided on the other end of the guide bar so as to be orthogonal to the guide bar, and a support plate A screw shaft supported in a reversely rotatable manner, a slider engaged with the guide bar so as to be movable in the axial direction of the guide bar, and a first differential screw formed on the outer peripheral surface with a hollow shape. And a nut supporting member formed to be screwed with the screw shaft, and a second differential screw formed in a hollow shape and screwed to the first differential screw on an inner peripheral surface. In a press device having a differential member formed to be rotatable with respect to the slider, and a drive member that rotationally drives the differential member,
A third screw including a zero pitch is provided on the outer peripheral surface of the differential member,
A fourth screw including a zero-pitch portion, which is placed on and fixed to the slider and is screwed with the third screw, is provided;
And provided with a rotation lock means placed on the slider to inhibit the rotation of the nut support member relative to the slider,
The press device, wherein the pitch between the first differential screw and the second differential screw is set to a different value with respect to the pitch between the third screw and the fourth screw. The nut support member includes a nut member provided with a nut screwed with the screw shaft, and a nut moving member provided with the first differential screw.
The press device according to claim 1, wherein the nut member and the nut moving member are fixed integrally. 2. The press according to claim 1, wherein the rotation lock unit is mounted so as to prevent the nut moving member from rotating and to move relative to the slider in an axial direction of the guide bar. apparatus. The drive member includes a pinion provided to be rotatable with respect to the slider,
The press apparatus according to claim 1, wherein the differential member includes a gear that is screwed with the pinion, and is supported rotatably with respect to the slider via the pinion and the gear. .

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