JP3405930B2 - Press equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press machine used for sheet metal working, for example, and more particularly to a press machine capable of fixed point machining which requires accurate position control.

[0002]

2. Description of the Related Art Conventionally, a fluid pressure cylinder has been widely used as a means for driving a ram contacting a work in a press working apparatus, and a hydraulic cylinder has been widely used.
In this press device driven by a hydraulic cylinder, when performing fixed-point machining, that is, machining in which the distance between the ram and the table is kept constant, it is necessary to perform machining commonly called "trunking".

FIG. 3 is an explanatory view showing a conventional barrel thrusting process. In FIG. 3, reference numeral 31 is a table, and a ram 32 of a press device is vertically moved with respect to the table 31 by a hydraulic cylinder, for example, so that a work 33 is pressed. In this case, in order to accurately machine the work 33 to the thickness t, the protrusion 3 corresponding to the thickness t is provided at the lower end of the ram 32 downward from the operating surface 34.
Project 5

When the ram 32 is operated downward with the above-described structure, the work 33 can be subjected to predetermined processing by the operating surface 34. However, when the protrusion 35 of the ram 32 contacts the table 31, the work 33 is processed. The thickness t is accurately ensured, machining can be performed without variation in dimensions, and the machining accuracy for the work 33 can be improved.

[0005]

In the processing mode shown in FIG. 3, the fixed point processing can improve the processing accuracy, but has the following problems. That is, in addition to the ram 32 impactingly contacting the work 33, the projecting portion 35 of the ram 32 also collides with the table 31 to generate a collision sound, and particularly the ram 32 per unit time. In the case of high-speed machining in which the number of times of operations is large, there is a problem that the noise becomes severe and the working environment is damaged.

On the other hand, fixed-point machining by an electric press has been conventionally used, and it is known that it is advantageous in preventing the generation of noise caused by the cylinder thrusting by the hydraulic press.

FIG. 4 is a longitudinal sectional view of an essential part showing an example of a conventional electric press, which is described in, for example, Japanese Patent Laid-Open No. 6-218591. In FIG. 4, reference numeral 41 is a pressing force generating means, which is housed in a head frame body 44 provided on a column 43 formed integrally with the table 42.

Reference numeral 45 denotes a cylindrical main body, which is provided in the head frame body 44 and has a bearing portion 46 at the upper end. Reference numeral 47 denotes a screw shaft, the upper end portion of which is supported by the bearing portion 46 and is formed in a suspended state. Next, 48 is a ram shaft, which is formed in a hollow cylindrical shape, a nut body 49 screwed with the screw shaft 47 is fixed to the upper end portion thereof, and is provided in the cylindrical main body 45 so as to be vertically movable. . Reference numeral 50 denotes a pressing body, which is detachably provided at the lower end of the ram shaft 48. The screw shaft 47 and the nut body 49 are engaged with each other by a ball screw.

Next, 51 is a steady rest, and the head frame 44
A guide portion 52 provided inside, a steady rod 53 provided vertically movable in the guide portion 52, and a connecting plate 54 provided at a lower end portion of the ram shaft 48 and the steady rod 53. There is. 55 is a drive motor, and the head frame 4
4, the screw shaft 47 is formed so as to be rotatable in the forward and reverse directions via a pulley 56 and a belt 57 provided at the upper end of the screw shaft 47.

It should be noted that the initial position of the pressing body 50, the fixed position stop point, the rotation speed of the drive motor 55, the forward / reverse direction, etc. can be given by a measuring means (not shown), a central processing unit or the like.

With the above structure, the screw shaft 47 is driven by the operation of the drive motor 55 via the belt 57 and the pulley 56.
When is rotated, the ram shaft 48, to which the nut body 49 is fixed at the upper end, descends, and the pressing body 50 contacts the workpiece W at a preset position and pressing force as shown by the chain line, and Processing is performed. After the processing is completed, the ram shaft 48 and the pressing body 50 are raised by the reverse rotation of the drive motor 55,
Return to the initial position. By repeating the above operation, it is possible to successively perform a predetermined fixed point machining on a plurality of workpieces W.

According to the electric press as described above, fixed point processing can be performed without generating noise, but the conventional one has the following problems. That is, the height dimension h of the lower end surface of the pressing body 50 from the table 42 in FIG. 4 is controlled so as to be always constant because of the fixed point processing, and at this position, the workpiece is processed via the pressing body 50. A predetermined pressing force is applied to W.
In other words, the reaction force corresponding to the pressing force acts on the screw shaft 47 and the nut body 49 at the same relative position at all times.

On the other hand, the screw shaft 47 and the nut body 49 are engaged with each other by a ball screw in order to accurately and accurately control the positions of the ram shaft 48 and the pressing body 50, and a ball forming a ball screw. The ball groove is engaged in line contact or point contact. For this reason, when the reaction force acts on the ball and the ball groove at the same relative position a number of times, the ball and / or the ball groove is locally worn, resulting in a decrease in machining accuracy and a short life. There is a problem. Incidentally, the screw shaft 47 and the nut body 4
Even when 9 and 9 are normal screw engagements, the above problems exist.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the problems existing in the above-mentioned prior art and to provide a press machine for fixed point machining which has high machining accuracy and long life.

[0015]

In order to solve the above-mentioned problems, in the present invention, a flat plate-shaped substrate,
A guide bar having one end portion on the substrate is provided so as to be orthogonal, a support plate formed on provided so as to be perpendicular to the guide bar and flat at the other end of the guide bar, this support A screw shaft supported by a plate parallel to the guide bar and rotatable in the forward and reverse directions, a movable body engaged with the guide bar so as to be movable in the axial direction thereof, and formed into a hollow cylindrical shape.
A nut member formed to be screwed with the screw shaft with made and having having a differential for male screw on the outer peripheral surface, the hollow cylinder
-Shaped and screwed on the inner peripheral surface with the differential male screw
A differential member having a female screw for differential and formed so as to be rotatable in the movable body, and fixed to the differential member.
Moreover , the technical means of using a worm wheel that engages with the worm is adopted.

In the present invention, the substrate and the support plate may be arranged parallel to the horizontal plane, and the axis of the guide bar may be arranged vertically.

Next, in the above invention, the screw shaft and the nut member can be engaged with each other by a ball screw. With such a configuration, the movable body can be moved smoothly and its positional accuracy can be improved.

In the above invention, the screw shaft and / or
Alternatively , the worm can be configured to be driven by a pulse motor.

[0019] In still above invention, a displacement of the movable body due to the rotation of the differential members offset by the rotation of the screw shaft, variable
The distance between the substrate and the movable body when the moving body is not operating can be kept constant.

[0020] Naoneji axis and thread pitch p ₁ and the differential for male thread and differential Me screw nut member and a pitch p ₂ may be p _1> p _2.

[0021]

1 is a vertical sectional front view of an essential part showing an embodiment of the present invention, and FIG. 2 is a sectional plan view of the essential part taken along the line AA in FIG. In both figures, 1 is a substrate, for example, is formed in a rectangular flat plate shape, for example, on its four corners cylindrical guide bar over 2 are erected. 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 a fastening member 4, for example.

Next, 5 is a screw shaft, which is rotatably supported in the central portion of the support plate 3 so as to pass through the bearing member 6 and penetrate the support plate 3. A movable body 7 is engaged with the guide bar 2 so as to be movable in the axial direction. 8 is a nut member, and a cylindrical portion 11 formed in the nut portion 10 and the hollow cylindrical shape having a flange portion 9 is formed by bonding together. Note nut portion 10 with screwed by 5 and the ball screw engagement the screw shaft, the outer peripheral surface of the cylindrical portion 11 providing a differential for ridge Ji 1 3.

[0023] 14 is a differential member, formed into a hollow cylindrical shape, the inner circumferential surface to the differential male screw 13 screwed to providing a 1 5 Flip sleep <br/> Me differential. A worm wheel 16 is integrally fixed to the differential member 14 and formed so as to engage with the worm 17. Reference numerals 18 and 19 respectively denote a radial bearing and a thrust bearing, which are provided in the movable body 7.
The differential member 14 and the worm wheel 16 are respectively supported.

Reference numeral 20 denotes a worm shaft, which is inserted into and fixed to the center of the worm 17, and both ends thereof are rotatably supported by bearings 21 and 21 provided in the movable body 7. Reference numerals 22 and 23 denote pulse motors, which are provided so as to rotate the screw shaft 5 and the worm shaft 20, respectively. Reference numeral 24 is a pusher, which is detachably provided on the lower surface of the central portion of the movable body 7. In addition, the pulse motor 22,
Reference numeral 23 is configured to be controllable by applying a predetermined pulse via a control device (not shown) .

With the above structure, when a predetermined number of pulses are applied to the pulse motor 22 to operate it, the screw shaft 5 rotates, the movable body 7 having the nut member 8 descends, and the pusher 2 is pressed.
4 descends from the initial height H ₀ to the fixed point processing height H and contacts the workpiece W. As a result, the fixed point machining is performed on the workpiece W with a preset pressing force via the pressing element 24. After the processing is completed, the movable body 7 is raised by the reverse operation of the pulse motor 22, and the pusher 24 returns to the position of the initial height H ₀ . The values of H ₀ and H are measured by a measuring 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. 1, that is, the position of the initial height H ₀ of the presser 24, and the pulse motor 23 is preset. Apply the set number of pulses. As a result, the pulse motor 23 rotates by a predetermined number, and the differential member 14 rotates by a predetermined central angle via the worm shaft 20, the worm 17, and the worm wheel 16. Due to the rotation of the differential member 14, 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.
The movable body 7 is displaced.

Since the initial height H ₀ of the pusher 24 naturally changes due to the displacement of the movable body 7, if the screw shaft 5 is rotated as it is, a predetermined fixed point machining cannot be executed. Therefore, next, a small number of controlled pulses are applied to the screw motor 5 to finely rotate the screw shaft 5 to cancel the displacement of the movable body 7 and the presser 24, and the initial height of the presser 24 is offset. The operation of holding the height H ₀ constant is performed.

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

In this case, the screw shaft 5 and the nut member 8
(Nut part 10) screw pitch is p ₁ , differential male screw 1
3 and the pitch of the differential female screw 15 is p ₂ ,
It is preferable that p ₁ > p ₂ . That is, p ₁ ≤p
_When it is ₂ , there is a possibility that the differential member 14 may be rotated in the opposite direction due to the reaction force when the pressing force is applied to the workpiece W by the pressing element 24, and such an undesired phenomenon is prevented. This is because. Further, it is also effective for keeping the displacement amount of the movable body 7 due to the rotation of the differential member 14 to a minimum value and performing the correction operation easily and quickly.

For example, the outer diameter of the ball screw constituting the screw shaft 5 is 63 mm, the screw pitch p ₁ is 16 mm, and the ball diameter is 9.5.
25mm (3/8 in.), Diameter between ball centers 65.7mm, 1
When the number of balls per circumference is 21 and the pitch p ₂ of the differential male screw 13 and the differential female screw 15 is 1.6 mm, the screw shaft 5 is rotated for one rotation of the differential member 14. The above correction operation is completed by rotating 1/10, that is, rotating by 36 °.

In addition to the above, when the ratio of the number of teeth between the worm 17 and the worm wheel 16 is, for example, 1/40, the worm 17 is rotated 4 times and the worm wheel 16 and the differential member 14 are rotated 1/10. The screw shaft 5 makes 1/100 rotation, that is, a rotation of 3.6 °, but the rotation distance on the circumference of the center of the ball is 2.06 mm, which also contributes to the ball and / or ball groove. It is quite possible to change the relative position with respect to.

In the embodiment of the invention described above, the so-called vertical type in which the substrate 1 and the support plate 3 are arranged in parallel with the horizontal plane and the guide bar 2 connecting them is provided in the vertical direction has been described. The present invention can also be applied to a so-called horizontal type in which the substrate 1 and the support plate 3 are provided in parallel with the vertical plane, and the guide bar 2 is provided in the horizontal direction.

Next, the present invention is particularly effective when the screw shaft 5 and the nut portion 10 constituting the nut member 8 are ball screw engaged, but both are normally screw engaged. It can also be applied. That is, the effect of preventing local wear due to application of a reaction force corresponding to the pressing force at the time of machining to only a specific portion of the screw and prolonging its life can be expected as well. Of course, it is also possible to use a multiple screw or a multiple thread screw, including those with ball screw engagement.

The pulse motors 22 and 23 for driving the screw shaft 5 and the worm shaft 20 generally have a structure in which they are directly connected coaxially to the shafts, but the transmission means such as a gear or a timing belt is used. May be configured to transmit power. It should be noted that the worm shaft 20 may be rotated manually, in short, as long as the information about the rotation speed of the worm shaft 20 is reflected in the pulse number of the pulse motor 22 for the correction operation and can be controlled. Good.

Further, it is preferable that the guide bar 2 for guiding the movement of the movable body 7 is large in number or is required to have rigidity, but it may be one, and in some cases, a columnar shape. Alternatively, it may be formed in a beam shape, and the movable body 7 may slide or slide along the side surface thereof.

Furthermore, the pressing device of the present invention is not limited to being used singly, but a plurality of units are arranged in tandem, and naturally applied to, for example, progressive feeding of a long workpiece. It is possible. Incidentally, the pressing device of the present invention, in addition to sheet metal working on a plate material, assembling a plurality of parts, press fitting,
It can also be used for processing such as caulking, and further for clamping a molding die in an injection molding machine, die casting, powder metallurgy and the like.

[0037]

EFFECTS OF THE INVENTION Since the present invention has the structure and operation as described above, the following effects can be obtained. (1) Since the relative position between the screw shaft for pressure application and the nut member can be changed appropriately even if the fixed point machining is continued, local wear can be prevented and the life can be extended. (2) Since the above-mentioned operation for changing the relative position can be performed extremely easily and in a short time, the ratio of actual work time is high, and highly efficient and highly efficient production is possible. (3) Since the lower end stop position of the movable body can be accurately controlled,
The processing accuracy can be improved. (4) It is possible to secure a quiet working environment without the noise as in a fluid pressure drive type.

[Brief description of drawings]

FIG. 1 is a front view of a longitudinal cross section of a main part showing an embodiment of the present invention.

FIG. 2 is a cross-sectional plan view of a main part taken along the line AA in FIG.

FIG. 3 is an explanatory view showing a conventional barrel thrusting process.

FIG. 4 is a longitudinal sectional view of an essential part showing an example of a conventional electric press.

[Explanation of symbols]

1 substrate 2 Guide bar 3 Support plate 5 screw shaft 7 movable body 8 Nut member 13 Differential male screw 14 Differential member 15 Female thread for differential 16 worm wheel 17 Worms

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) B30B 1/18 B30B 15/06 B30B 15/14

Claims (7)

(57) [Claims] 1. A substrate formed in a flat plate shape, and a guide bar provided on the substrate so that one end thereof is orthogonal to each other,
A support plate the other end portion of the guide bar is provided to be orthogonal to the guide bar and which is formed in a plate shape, the guide bar parallel to and forward and reverse rotatable supported screw shaft to the support plate A movable body engaged with the guide bar so as to be movable in the axial direction thereof, and formed in a hollow cylindrical shape.
A nut member formed to be screwed with the screw shaft and having a differential for male screw on the outer peripheral surface, the formation of hollow cylinder
And a differential eyeglass that is screwed onto the inner peripheral surface of the differential male thread.
A differential member that has a stirrup and is rotatably formed in the movable body ;
A press device comprising a worm wheel that engages with a diaphragm . 2. The press apparatus according to claim 1, wherein the substrate and the support plate are arranged in parallel with a horizontal plane, and the axis of the guide bar is arranged in the vertical direction. 3. The press device according to claim 1, wherein the screw shaft and the nut member are engaged with each other by a ball screw. 4. The press device according to claim 1, wherein the screw shaft is configured to be driven by a pulse motor. 5. The press device according to claim 1, wherein the worm is configured to be driven by a pulse motor. 6. A structure in which the displacement of the movable body due to the rotation of the differential member is offset by the rotation of the screw shaft, and the distance between the substrate and the movable body is kept constant when the movable body is not operating. The press device according to any one of claims 1 to 5. 7. The screw pitch p of the screw shaft and the nut member.
₁ and claims 1, characterized in that the pitch p ₂ of the differential for the external thread and the differential female screw was p _1> p ₂ press apparatus according to 6 or.