WO2004080703A1

WO2004080703A1 - Electrically driven press machine

Info

Publication number: WO2004080703A1
Application number: PCT/JP2004/001330
Authority: WO
Inventors: Shoji Futamura; Keizo Unno
Original assignee: Hoden Seimitsu Kako Kenkyusho Co., Ltd.
Priority date: 2003-03-14
Filing date: 2004-02-09
Publication date: 2004-09-23
Also published as: TWI232800B; TW200418633A; KR20040080973A; JP2004276053A

Abstract

An electrically driven press machine has a frame body (4), a slider (5) that has an upper die (6) installed to it and slides on struts (3), a connection mechanism for vertically moving the slider (5) through a ball screw shaft (19) rotated in forward and reverse directions by an AC servomotor (9), a lower die (22), a stepless speed changer (10) that is provided between the AC servomotor (9) and the ball screw shaft (19), a pulse scale (23) for detecting the position of the upper die (6), and a control device (25) that, based on a position signal detected by the pulse scale (23), sets the AC servomotor (9) to a torque-added mode in a press position period where the upper die (6) presses an object (24) to be pressed placed on the lower die (22), and rapidly lowers and raises the upper die (6) through the switching of the stepless speed changer (10) in a non-pressing period that is the period other than the press position period.

Description

Description Electric press machine Technical field

The present invention relates to an electric press working machine, and particularly to an electric press working machine that performs press working using a motor as a drive source by an upper die attached to a lower end of a slider that reciprocates and a lower die attached to a bed. In, the upper die at the upper limit standby position descends and comes into contact with the workpiece placed on the lower die or just before the contact, and the upper die rises from the lower limit position and returns to the upper limit standby position. The present invention relates to an electric press machine in which the upper die is moved at a high speed during each time until the one step (cycle) of the press is shortened. '' Background technology

Conventionally, in an electric press machine that performs press working using a motor as a drive source, the speed at which the work is pressed is determined by the speed of the upper die that performs the press work, and the stage where the work is not pressed However, in general, reciprocating motion was performed at a constant low speed, which is the speed of the upper die when the upper workpiece is pressed.

In the stage where the work is not pressed as in the past, the press process is performed in accordance with the speed of the upper die when the work is pressed. there were.

To solve this drawback, Patent Document 1 discloses that two motors are used as one set of drive sources among one or more sets of drive sources, and the upper die is pressed by the first motor among them. An electric press machine that moves the workpiece to the vicinity of the processing position in a short time and then presses the workpiece into a predetermined shape by moving the upper mold to the lower mold by the second motor for press working has been released. ing.

However, in the prior art disclosed in Patent Document 1, the first motor 66 for high-speed descent / upward movement that operates during a so-called non-pressing period and the second motor for a press-working mode that operates during a so-called press period are used. Two drive motors with two motors 6 7 In addition, the control of the electric press machine was complicated as well as the overall configuration of the electric press machine. The equipment itself was large, and the cost was high because two drive motors were used separately.

An object of the present invention is to solve the above-mentioned drawbacks. In a stage in which a single drive motor is used as a set of drive sources to move up and down all, and a workpiece during a so-called press working period is not subjected to press working. An object of the present invention is to provide an electric press machine capable of shortening the time required for one step of press working by moving the upper mold at high speed, and at the same time, increasing the torque during working.

[Patent Document 1] Japanese Published Patent Application No. 200 1--6 2 597 Disclosure of the Invention

An object of the present invention is to reduce the time required for one step of press working by switching the continuously variable transmission during a non-press period other than the press working period, and at the same time, increase the torque during the press working period. An object of the present invention is to provide an electric press machine that can be peeled off.

Another object of the present invention is to provide a control device suitable for reducing the time required for one step of press working.

Still another object of the present invention is to provide a continuously variable transmission that can reduce the time required for one step of press working and increase the torque during the press working period.

Still another object of the present invention is to provide a V-belt type continuously variable transmission having a structure suitable for a press machine.

Still another object of the present invention is to provide a connecting mechanism suitable for vertically moving a slider to which an upper die is attached.

Still another object of the present invention is to provide a coupling mechanism that ensures the accuracy of processing by a press machine.

Still another object of the present invention is to provide ball bearing position adjusting means for ensuring the durability of a press machine.

Still another object of the present invention is to appropriately operate the control timing of the control device. To provide a position detector.

In the disclosed embodiment, a frame formed of a bed, a crown, and a plurality of columns, a slider having a configuration in which an upper die is attached to a lower end surface and the columns are freely slid, and a drive motor A coupling mechanism for moving the slider up and down via a screw shaft driven in reverse rotation by a reverse rotation, and a lower die fixed to the bed at a position corresponding to the upper die. Contact between the continuously variable transmission provided between the drive motor shaft and the screw shaft, and the workpiece placed on the upper and lower dies A position detector that detects the position and detects the upper and lower standby positions and lower descent positions of the upper die, and a workpiece on which the upper die is mounted on the lower die based on the position signals detected by the position detector. During the non-pressing period other than the press working period And a control device for rapidly lowering and raising the upper die through switching of the step transmission. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an explanatory view of a main part of an embodiment of an electric press working machine according to the present invention.

FIG. 2 is an enlarged explanatory view of one embodiment of the continuously variable transmission.

FIG. 3 is a sectional view for explaining the structure of an embodiment of the differential mechanism.

FIG. 4 is a cycle diagram of an embodiment of the electric press machine according to the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is an explanatory view of a main part of an embodiment of an electric press working machine according to the present invention. In FIG. 1, sliders 5 are provided inside a frame 4 formed by a bed 1, a crown 2, and a plurality of columns 3, and the four corners of the slider 5 are engaged with the columns 3 to engage with the axes of the columns 3. Sliding holes in which the slider 5 freely slides in the directions are provided. The upper die 6 is attached to the lower end surface of the slider 5.

At the top of the crown 2, a mounting base 7 is provided. An AC servomotor 9 having a built-in encoder 8 is mounted on the mounting base 7, and two pulse motors 11 and 12 constituting a continuously variable transmission 10 are mounted on the mounting base 7.

Gears 13 and 2 fixed to the shaft of the AC servomotor 9 inside the mounting base 7 V pulleys 14, 15, and these two V pulleys that constitute a continuously variable transmission 10 slidably mounted in the axial direction of the motors 11, 12 on the shafts of the motors 11, 12. Contains V-belt 16 hung on 14 and 15.

The gear 13 fixed to the shaft of the AC servomotor 9 is engaged with the gear 17 provided at one end of the V pulley 14, and the V pulley 15 to which the rotational force is transmitted via the V belt 16. The gear 18 provided at one end of the gear 5 is engaged with the gear 20 fixed to the tip of a ball screw shaft 19 provided through the threaded portion of the screw portion of the crown 2. In addition, a differential mechanism 21 (the differential mechanism 21 will be described in detail in FIG. 3 later) is fixed corresponding to the ball screw shaft 19.

The ball screw shaft 19 is screwed with a differential mechanism 21 having a ball and a nut member provided therein. The ball screw shaft 19 and the differential mechanism 21 couple the crown 2 and the slider 15 together. It has a linked structure. That is, when the AC servo motor 9 provided on the mounting base 7 is rotated forward or backward, the slider 5 is raised or lowered via the continuously variable transmission 10, and the slider 5 is reciprocated by the rotation control of the AC servo motor 9. Can exercise. In addition, the two pulse motors 11 and 12 are rotated, and the actual diameter ratio of the two V pulleys 14 and 15, that is, the ratio of the pitch circle diameter of the V pulley 14 to the pitch circle diameter of the V pulley 15 By changing the speed, the movement speed of the slider 5 can be changed.

A lower mold 22 is fixed to the bed 1 at a position corresponding to the upper mold 6, and a pulse scale 23 for detecting the position of the slider 5 is attached between the bed 1 and the crown 2. The contact position between the workpiece 24 placed on the lower mold 22 and the upper mold 6 is detected, and the upper-limit standby position and the lower-limit lowering position of the upper mold 6 are detected.

The control device 25 that controls the rotation of the AC servo motor 9 and the two pulse motors 11 and 12 that constitute the continuously variable transmission 10 is configured such that various set values are input in advance. , Based on the position signal detected by the pulse scale 23 for detecting the position of the slider 5, when the upper die 6 at the upper limit standby position comes into contact with the workpiece 24 placed on the lower die 22 Alternatively, until the point immediately before the contact, the upper die 6 is rapidly lowered via the continuously variable transmission 10 and the upper die 6 comes into contact with the workpiece 24 or Means that the upper die 6 is continuously lowered from the point immediately before contacting to the point where the upper die 6 descends to the predetermined lower limit drop position (the imaginary line position (6) of the upper die 6 in FIG. 1). The speed is reduced via the transmission 10, the AC servomotor 9 is set to the torque addition mode, the upper die 6 presses the lower die 22, and control is performed to press the workpiece 24 into a predetermined shape. After a lapse of a predetermined time in which the upper die 6 is at the lower limit position, control for rapidly raising the upper die 6 via the continuously variable transmission 10 is performed.

FIG. 2 is an enlarged explanatory view of one embodiment of the continuously variable transmission, and the same components as those in FIG. 1 are denoted by the same reference numerals.

In the figure, rotatable ball screw shafts 26 and 27 each having a positive screw and a reverse screw cut off are fixed to the respective axes of the pulse motors 11 and 12. At the base and tip of the ball screw shaft 26, guide keys 28 and 29 are attached to the mount 7 so that the pole screw shaft 26 can rotate freely. Similarly, guide keys 30 and 31 are attached to the mounting base 7 so that the ball screw shaft 27 can rotate freely, at the base and the tip of the ball screw shaft 27.

A nut member 33 screwed into the ball screw shaft 26 via a plurality of balls (not shown) at the root side of the pulse motor 11 is a bearing on one pulley piece 3 4 constituting the V pulley 14. The nut member 33 has a structure guided by the tip of the guide key 28. Similarly, a nut member 36 screwed into the ball screw shaft 26 via a plurality of poles (not shown) on the distal end side of the pulse motor 11 is provided with a bearing on one pulley piece 3 7 constituting the V pulley 14. The nut member 36 is provided with a structure guided by the tip of the guide key 29. The structure of a ball screw mechanism and the like that are screwed together with the ball screw shaft 26 and the nut members 33 and 36 via a plurality of balls will be described in detail in FIG.

When the pulse motor 11 is rotated, the two pulley pieces 3 4 and 37 constituting the V pulley 14 move in a direction approaching or moving away from each other, and the pulley diameter of the V pulley 14 is reduced. While changing continuously, the two pulley pieces 34 and 37 are integrated by a fixing pin 39 that rotates the two pulley pieces 34 and 37 integrally. Also, a plurality of balls (not shown in the figure) are attached to the ball screw shaft 27 at the base of the pulse motor 12. The nut member 40 that is screwed through the nut is attached via a bearing 42 to one pulley piece 41 that forms the V pulley 15, and the nut member 40 is connected to the guide key 30. It has a structure guided by the tip. Similarly, the nut member 43, which is screwed into the ball screw shaft 27 via a plurality of balls (not shown) at the tip end side of the pulse motor 12, bears a pulley piece 4 4 constituting the V pulley 15 The nut member 43 is provided with a structure guided by the leading end of the guide key 31. The structure of the ball screw mechanism, which is screwed through a plurality of balls of the ball screw shaft 27 and the nut members 40 and 43, will be described later in detail with reference to FIG. In the mechanism, there is no ball bearing position adjusting means described later in FIG. 3, but the ball bearing position adjusting means may be provided).

When the pulse motor 12 is rotated, the two pulley pieces 4 1 and 4 4 constituting the V pulley 15 move in a direction approaching or moving away from each other, and the pulley diameter of the V pulley 15 is reduced. While changing continuously, the two pulley pieces 41 and 44 are integrated by a fixing pin 39 that integrally rotates the two pulley pieces 41 and 44. Then, the two pulse motors 11 and 12 receive a signal from the control device 25 (see FIG. 1) for synchronously rotating the two pulse motors 11 and 12 in opposite directions. When the pitch circle diameter of the V pulley 14 on the motor 11 side increases, the pitch circle diameter of the V pulley 15 on the pulse motor 12 side decreases. The pitch circle diameter ratio between V pulleys 14 and 15 increases, and the rotation speed of V pulley 15 transmitted by V belt 16 increases. Conversely, when the pitch circle diameter of the V pulley 14 on the pulse motor 11 side decreases, the pitch circle diameter of the V pulley 15 on the pulse motor 12 side increases. The pitch circle diameter ratio between V pulleys 14 and 15 becomes smaller, and the rotation speed of V pulley 15 transmitted by V belt 16 decreases.

In other words, the rotation of the gear 13 attached to the shaft of the AC servomotor 9 is controlled by the continuously variable transmission mechanism 10 provided inside the mounting base 7, and the gear 2 fixed to the ball screw shaft 19 The rotation is transmitted to 0 by a continuously variable transmission.

FIG. 3 is a sectional view for explaining the structure of an embodiment of the differential mechanism. The present applicant has filed a patent application for the differential mechanism as PCTZJP01-090956. The differential mechanism 21 used in FIG. 1 has the structure shown in FIG. 3, and the differential mechanism 21 includes a ball screw shaft 19, a plurality of balls 50, and a nut member 51. The ball bearing consists of The ball screw mechanism of the ball screw shaft 26 and the nut members 33, 36 and the ball screw shaft 27 and the nut members 40, 43 described in FIG. It has the same mechanism as a ball bearing comprising 9, a plurality of balls 50 and a nut member 51.

In FIG. 3, a ball bearing position adjusting means having a movable member 52, a differential member 53, and a receiving member 54 is further provided.

The nut member 51 is provided with a ball groove 55 in the center of the ball screw shaft 19 which engages with the ball screw shaft 19 via the ball 50. The ball screw shaft 1 via the ball 50 The pole screw engagement between the nut 9 and the nut member 51 enables accurate and highly accurate position control of the upper die 6.

At the lower end of the nut member 51, a movable member 52 having a hole for allowing the ball screw shaft 19 to pass therethrough is fixed at the center, which belongs to the ball bearing position adjusting means. At the center, between the movable member 52 and a receiving member 54 having a central portion provided with a hole through which the ball screw shaft 19 penetrates and having an inclined surface 56 formed at the upper end surface. A hole is provided to allow the ball screw shaft 19 to penetrate and to allow its own sliding. Then, the differential member 53 whose lower end surface is formed with the same inclination angle as the inclined surface 56 formed on the receiving member 54 at the same inclination angle as the inclined surface 56 is positioned in the left-right direction of the drawing (A in FIG. 3). The nut member 51 slides only in the vertical direction (both directions of the arrow B in FIG. 3) via the movable member 52 (the nut member 51 in FIG. 3). The restraint mechanism that moves only in the vertical direction is not shown). By rotating the screw portion 57 with a pulse motor or manually and moving the nut member 51 a small distance in the vertical direction, the line between the pole 50 and the ball groove 55 that constitute the ball screw is formed. For ball screws that engage in contact or point contact, avoid local wear of the pole 50 or ball groove 55 caused by engaging in line or point contact at the same position at all times under load be able to.

That is, when the upper die 6 reaches the lowest point, a maximum load is generated to further lower the upper die 6, but the same upper die 6, the same lower die 22 and the same workpiece 24 are generated. Use When machining is continued, the ball screw shaft 19 at the maximum load, the ball 50, and the ball groove 55 of the nut member 51 are aligned with the pole screw shaft 19 and the pole 50 under the same fixed positional relationship. Contact locally, and this contact portion is locally worn. With the use of the differential mechanism 21, the differential member 53 is inserted or ejected in each direction of the arrow A at each press working or at each predetermined press working (for example, about five times). As a result, the positional relationship between the ball screw shaft 19, the ball 50, and the ball groove 55 of the nut member 51 at the maximum load slightly shifts, and wear is prevented. The situation in which the differential member 53 is removed is such that, with a single insertion, the above-mentioned contact portion shifts by about 2 μm on the large diameter of the ball 50 with a diameter of about 10 mm. . In this way, the contact point goes around the large diameter of the ball 50 by inserting the differential member 53 about 157 000 times.

The operation of the thus-configured electric press machine of the present invention will be described with reference to a cycle diagram of one embodiment in the automatic operation shown in FIG.

In FIG. 4, the vertical axis represents the stroke and the horizontal axis represents the time, and the solid line represents the press locus, that is, the locus of the upper die 6.

T0 on the time axis indicates the cycle start time when the upper die 6 is at the upper limit standby position, T1 on the time axis indicates the start time of the lowering of the upper die 6, and T2 on the time axis indicates that the upper die 6 is at the lower position. The time point T 3 on the time axis represents the time point at which the upper mold 6 reaches a predetermined lower limit descent position, and the time point T 3 on the time axis represents the time point of contact with the surface of the flat work piece 24 placed on the mold 22. 4 indicates the time when the upper die 6 starts to rise from the lower limit descent position, T5 on the time axis indicates the time when the upper die 6 reaches the upper limit standby position, and T6 on the time axis indicates the time when one cycle is completed. . In other words, the time T 1 to T 2 is a non-pressing period from the upper limit standby position of the upper die 6 to contact with the workpiece 24 placed on the lower die 22, and the V pulley of the continuously variable transmission 10. 14 and 15 are set to the pitch circle diameter ratio for rapidly lowering the upper die 6, and lowering the upper die 6 rapidly. In other words, the time Τ2 to Τ4 is a press period in which the AC servomotor 9 is in the torque adding mode, and the upper die 6 presses the workpiece 24 placed on the lower die 22. The V pulleys 14 and 15 of the step transmission 10 are reduced to the press mode pitch circle diameter ratio, and the time T4 to T5 is from when the upper die 6 returns from the lower limit lowering position to the upper limit standby position. During the non-pressing period, the continuously variable transmission 10 V pulleys 14 and 15 are on The pitch circle diameter ratio is set so that the die 6 rises rapidly, and the upper die 6 rises rapidly. In this way, the time required for one step (cycle) of press working is reduced.

In the above description, as an example of the continuously variable transmission 10, a belt-type continuously variable transmission with a reliable power transmission has been described. However, a chain-type continuously variable transmission with a reliable power transmission may be used. .

The ball screw shafts 26 and 27 are used for the pulse motors 11 and 12, and the pitch circle diameter of the V pulleys 14 and 15 is changed by the ball screw mechanism. The pitch circle diameters of the V pulleys 14 and 15 may be changed.

Further, a pulse scale is used as a position detector for detecting the contact position between the workpiece 24 placed on the lower mold 22 and the upper mold 6 and detecting the upper standby position and the lower lower limit position of the upper mold 6. Although reference numeral 23 is shown, any other electronic or mechanical position detector can be used as long as it can detect the position and can send a detection signal to the control device 25. Industrial applicability

As described above, according to the present invention, the stepless transmission is used in the electric press working machine having a single press drive motor configuration, and the upper die is moved at high speed in the process of not performing press working. The time required for one step (cycle) of press working can be shortened, and at the same time, the torque can be increased during working.

In an electric press machine, a plurality of sets of drive sources may be used to simultaneously generate a driving force to drive press the upper die. In such an electric press machine having a plurality of sets of drive sources, the single press drive motor described above may be a single press drive motor of the plurality of drive sources. It means that a drive motor is used.

Claims

The scope of the claims

1. A frame formed of a bed, a crown, and a plurality of columns, a slider having an upper die attached to the lower end surface and freely sliding the columns, and driven forward and backward by a drive motor. Electric press working, which includes a connection mechanism that moves the slider up and down via a screw shaft that is fixed, and a lower die that is fixed to the bed at a position corresponding to the upper die, and presses the workpiece with the upper die and the lower die. On the machine,

A continuously variable transmission provided between the drive motor shaft and the screw shaft,

A position detector that detects a contact position between the upper mold and the work placed on the lower mold, and detects an upper standby position and a lower lower position of the upper mold;

During the press-ready period in which the upper die presses the workpiece placed on the lower die based on the position signal detected by the position detector, the drive motor is in the torque addition mode, and the press die is not in the press-ready period. During the non-pressing period, a control device that rapidly lowers and raises the upper mold through the

An electric press machine comprising:

2. Based on the position signal detected by the position detector, the above-mentioned control unit uses the continuously variable transmission until the upper mold touches or comes into contact with the workpiece placed on the lower mold. The upper die is rapidly lowered, and the upper die is continuously lowered from the time when the upper die comes into contact with the workpiece or immediately before the contact to the time when the upper die descends to the predetermined lower limit descent position. Decelerates via the transmission, sets the drive motor to the torque addition mode, and controls the upper die to press the work placed on the lower die, and the specified time has elapsed when the upper die is at the lower limit lowering position 2. The electric press working machine according to claim 1, wherein the upper die is raised rapidly via a continuously variable transmission.

3. The continuously variable transmission is composed of two pulse motors and two pulley pieces, and the two stepper motors are provided with respective shafts of the two pulse motors in a direction approaching or moving away from each other in the axial direction. A V-belt type continuously variable transmission including two V-pulleys in which two pulley pieces are provided movably and a pitch circle diameter is variable, and a V-belt hung on the two V-pulleys is used. 2. The electric press working machine according to claim 1, wherein

4. Each axis of the pulse motor has a ball screw shaft in which a positive screw and a reverse screw are respectively cut, and a nut member screwed to the ball screw shaft via a plurality of balls has a V member. 4. The electric press working machine according to claim 3, wherein each of the pulley pieces constituting the pulley is mounted via a bearing.

5. The electric press working according to claim 3, wherein a normal screw mechanism is used for each axis of the pulse motor, and the pitch circle diameter of the V pulley is changed. Machine.

6. The electric press working machine according to claim 1, wherein the continuously variable transmission is a chain-type continuously variable transmission.

7. The connecting mechanism for moving the slider up and down has a nut member provided with a plurality of balls and ball grooves, a differential mechanism fixed to the slider, and screwed with the differential mechanism to rotate on the crown. 2. The electric press machine according to claim 1, further comprising a ball screw mechanism having a freely supported ball screw shaft.

8. The differential mechanism of the coupling mechanism that moves the slider up and down must have a pole bearing position adjusting means that shifts the contact position between the ball groove of the pole and the nut member and the contact position of the ball and the pole groove of the ball screw shaft. The electric press working machine according to claim 7, characterized in that:

9. The ball bearing position adjusting means is provided with a movable member having a hole at the center for penetrating the ball screw shaft, a hole at the center for penetrating the ball screw shaft, and an upper end surface. A hole is provided between the movable member and the receiving member having an inclined surface formed therein, and a hole sufficient to allow the ball screw shaft to pass therethrough and to allow its own movement is provided at the center, and a lower end surface A differential member having the same inclination angle as the inclined surface formed on the receiving member and an inclined surface opposite to the inclined surface, and a differential member perpendicular to the center line of the ball screw shaft and in the above inclination angle direction. 9. The electric press working machine according to claim 8, further comprising: a restraining mechanism that moves the movable member by a minute distance only in the axial direction of the ball screw when the member is slid.

10. The position detector is a pulse scale provided between the bed and the crown. 2. The electric press working machine according to claim 1, wherein the position of the upper die is detected from the tool.