JP5420924B2 - Electric servo press - Google Patents

Description

  The present invention relates to an electric servo press.

  Conventionally, as a relatively small electric servo press having excellent versatility, a structure in which the slide is moved up and down by pushing and pulling a toggle link mechanism connected to the slide with an eccentric mechanism is known (for example, , See Patent Document 1).

However, since the toggle link mechanism of such an electric servo press is configured to include a pair of links arranged in series in the vertical direction, even though it is small, it has a considerable height dimension, and has a large blow-off space. In a building (factory) where it is difficult to secure, there are cases where it cannot be easily installed. In addition, the provision of an eccentric mechanism is a factor that increases the overall height.
Furthermore, in the electric servo press provided with the toggle link mechanism, the pair of links and the eccentric mechanism are connected by a triaxial (triangular) link. Play is likely to occur.

  In order to solve such a problem, it has been proposed to move the slide up and down by a slider crank mechanism (see, for example, Patent Document 2). In addition, it is possible to directly connect a servo motor as a drive source to the eccentric shaft of the slider crank mechanism, and the overall height can be more reliably suppressed by omitting a reduction gear, a large-diameter pulley, and the like. In addition, if a hollow servomotor is used as the electric servomotor, the motor itself can be reduced in size and the overall height can be further reduced.

JP 2004-017098 A JP 2006-255745 A

However, hollow servo motors are ordered as special orders from motor manufacturers according to the press capacity (capacity). Therefore, if you try to line up the different servo motor product lineups as a product system, a custom-made hollow servo with different specifications The number of motors increases, making it very expensive.
In addition, in the existing electric servo press installed in the press line, it will take a lot of time to obtain a hollow servo motor with different specifications for the request to change the press capacity, There is also a problem that it cannot be dealt with immediately.

  An object of the present invention is to provide an electric servo press that can be manufactured at a low cost and can quickly cope with a change in capacity.

An electric servo press according to the present invention includes a main body frame composed of a plurality of plate-like frame members, a bolster installed on the lower front surface of the main body frame, and a slider crank mechanism provided on the upper portion of the main body frame. A slide movably connected to the slider crank mechanism and a hollow servo motor for driving the slider crank mechanism, and the slider crank mechanism is inserted into the hollow servo motor and driven by the hollow servo motor. An eccentric shaft, a slider crank that is slidably provided on the outer periphery of the eccentric shaft, and an outer periphery that is eccentric with respect to the inner periphery, and a slider crank that is slidably provided on the outer periphery of the slider crank and that moves up and down. and a universal and has been slider connecting rod, the upper portion of the body frame, wherein the plurality of frame Formed in a box shape by arm member, housing space hollow servomotor different numbers according to the press capacity is accommodated is provided in advance, the eccentric shaft, the ones having a length corresponding to the number of the hollow servo motor It is characterized by being exchanged .
The electric servo press according to the present invention includes a main body frame composed of a plurality of plate-like frame members, a bolster installed on the lower front surface of the main body frame, and a slider crank provided on the upper portion of the main body frame. A mechanism, a slide coupled to the slider crank mechanism so as to freely move up and down, and a hollow servo motor for driving the slider crank mechanism,
The slider crank mechanism is provided with an eccentric shaft that is inserted into the hollow servomotor and driven by the hollow servomotor, and is slidably provided on the outer periphery of the eccentric shaft, and the outer periphery is eccentric with respect to the inner periphery. A slider crank, and a slider connecting rod that is slidably provided on the outer periphery of the slider crank and is movable up and down, and is formed in a box shape by the plurality of frame members on the upper part of the main body frame; Storage spaces for accommodating different numbers of hollow servomotors corresponding to the press capacity are provided in advance, and the eccentric shaft is supported by a bearing plate erected on the body frame, and the number of the hollow servomotors is The bearing plate can be replaced with a length corresponding to the length of the eccentric shaft. Flip and upright position is changed.

In the electric servomotor of the present invention, when a plurality of hollow servomotors are accommodated in the accommodation space, it is desirable that these hollow servomotors have the same specifications.
Here, “the specifications are the same” means the same outer shape, output, torque, rated rotational speed, etc., such as having the same model number.

  In the electric servomotor of the present invention, the slide may be connected to the slider connecting rod via a wrist pin.

According to the present invention, by employing a slider crank mechanism including a slider crank and a slider connecting rod, mechanical backlash is eliminated, molding accuracy and rigidity are excellent, and the overall height can be reliably reduced. Further, in the present invention, since a storage space for storing a different number of hollow servomotors corresponding to the press capacity is provided in advance, if a larger press capacity is desired, a larger number of hollow servomotors are provided. It is only necessary to house the eccentric shaft and drive it. If the specifications of the hollow servo motor are limited at this time, the types of hollow servo motors can be reduced and can be ordered without special orders. As a result, electric servo presses can be manufactured at low cost. In addition, by limiting the specifications of the hollow servo motor, it is possible to shorten the delivery time from ordering to delivery of the hollow servo motor, so that it is possible to respond quickly to capacity changes.
As described above, it is possible to promote the grouping due to the difference in press capability as a product system of the electric servo press.

  When multiple hollow servomotors are used, if the specifications are all the same, one type of hollow servomotor may be used, which can be manufactured at a lower cost, and can respond more quickly to changes in capacity. Because of the single type, management can be facilitated.

  When the slider connecting rod and the slide are connected via the wrist pin, the mechanical backlash does not increase significantly. Rather, this backlash can absorb the tilt of the slide due to the eccentric load during molding, and molding. Can be improved.

1 is a front view showing a partial cross section of an electric servo press according to a first embodiment of the present invention. It is a sectional side view of the said electric servo press, and the II-II sectional view taken on the line of FIG. The sectional side view which shows the case where the number of attachment of a hollow servomotor is changed. The sectional side view of the electric servomotor which concerns on 2nd Embodiment of this invention.

[First Embodiment]
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment of the invention will be described with reference to the drawings. FIG. 1 is a front view showing a partial cross section of an electric servo press 1 according to the present embodiment. FIG. 2 is a side cross sectional view of the electric servo press 1, and is a cross-sectional view taken along the line II-II in FIG.

  1 and 2, an electric servo press 1 includes a main body frame 2 composed of a plurality of plate-like frame members, a bolster 3 installed on the lower front surface of the main body frame 2, and an upper portion of the main body frame 2. The slider crank mechanism 4 provided, a slide 5 connected to the slider crank mechanism 4 so as to be movable up and down, and a hollow servo motor 6 that drives the slider crank mechanism 4 are provided.

  Specifically, the main body frame 2 includes a pair of vertical plate-like frames 21 that form both sides, and a thick plate-like slide support frame 22 fixed inside each plate-like frame 21, and the front side is open. The whole is formed in a C shape. On the lower side of the main body frame 2, the plate-like frames 21 (slide support frames 22) are connected by plates 23 and 24. The bolster 3 is supported on the lower side of the plates 23 and 24 and the frames 21 and 22, and the slide 5 is supported on the upper portion of the slide support frame 22 so as to be movable up and down.

  The upper side of the main body frame 2 is formed in a box shape by the plate-shaped frame 21, the support plate 25, the top plate 26, the front plate 27, and the like, and the slider crank mechanism 4 and the hollow servo motor 6 are accommodated therein. The lower surface of the support plate 25 and the upper part of the slide support frame 22 are connected by a vertical connection plate 28. However, the specific structure of the main body frame 2 is not limited to that of the present embodiment, and may be arbitrarily determined for the implementation.

  The slider crank mechanism 4 includes an eccentric shaft 41 driven by the hollow servomotor 6, a slider crank 42 that swings in the circumferential direction by the rotation of the eccentric shaft 41, and a slider connecting rod 43 that moves up and down by the swing of the slider crank 42. It has.

  The eccentric shaft 41 is integrally formed with an eccentric drum 44 at a position on the front side (front side) in the longitudinal direction, and is supported by bearing plates 11 and 12 provided on the main body frame 2 before and after the eccentric drum 44. Has been. The eccentric shaft 41 is long on the rear side from the portion supported by the bearing plate 12, and the rear end side is supported by the bearing plate 13 that is erected further rearward than the hollow servomotor 6.

  The slider crank 42 is formed in an annular shape whose outer periphery is eccentric with respect to the inner periphery, and the inner periphery is slidably disposed on the outer periphery of the eccentric drum 44 via a bush (not shown). Here, in the thin wall portion where the inner and outer circumferences of the slider crank 42 are closest, the slide 5 has a top dead center (a position indicated by a two-dot chain line in FIG. 1) and a bottom dead center (a position indicated by a solid line in FIGS. 1 and 2). Is located directly below the eccentric shaft 41. With this configuration, the moving speed at the bottom dead center position of the slide 5 is reduced, and the formation accuracy can be improved.

  A flat surface 45 having a two-surface width is formed on the outer periphery of the slider crank 42. The flat surface 45 is formed along the eccentric direction of the inner and outer circumferences of the slider crank 42. In this way, by omitting both sides of the slider crank 42, the weight is reduced as compared with the case where the slider crank 42 is circular. The outer periphery of the slider crank 42 is slidably disposed in a circular opening 46 provided in the slider connecting rod 43 via a bush (not shown).

  The slider connecting rod 43 has a substantially pentagonal shape having a pair of vertical sliding portions 47 on both the left and right sides. The sliding portion 47 is in contact with a guide portion 29 provided on the inner surface of the plate-like frame 21, and the entire slider connecting rod 43 slides up and down while being guided by the guide portion 29. On the lower side of the slider connecting rod 43, a rod portion 48 hanging downward is integrally provided. The rod portion 48 is connected to the plunger 51 of the slide 5 via a wrist pin 49.

  As described above, the slider crank mechanism 4 has a structure in which mechanical backlash hardly occurs between the eccentric shaft 41 and the slider connecting rod 43 as compared with the toggle link mechanism, and can realize excellent molding accuracy. is there. In addition, since the structure is less likely to cause backlash, the rigidity is increased and the capacity limit can be further increased.

  On the other hand, the slider crank mechanism is normally directly connected to the slide 5, but in this embodiment, the slider crank mechanism 4 and the slide 5 are connected via the wrist pin 49, The slight backlash absorbs the inclination of the slide 5 due to the uneven load at the time of molding and suppresses the main body frame 2 from being greatly distorted.

  The slide 5 has a structure in which a plunger 51 and a slide body 52 below the plunger 51 are connected by a screw shaft 53. That is, a female screw is engraved on the plunger 51, and a male screw portion engraved on the upper side of the screw shaft 53 is screwed to the female screw portion. A lower side of the screw shaft 53 is rotatably attached to the slide body 52.

  In the slide body 52, a worm wheel 54 is provided on the outer periphery on the lower end side of the screw shaft 53. A worm (not shown) is engaged with the worm wheel 54. The worm is rotationally driven by an induction motor 55 provided on the back surface of the slide body 52, and this rotation is transmitted to the screw shaft 53 via the worm wheel 54. The slide body 52 moves up and down by the rotation of the screw shaft 53, and the die height can be adjusted.

  In the electric servo press 1 shown in FIG. 2 of the present embodiment, two hollow servo motors 6 are used along the axial direction of the eccentric shaft 41 in order to realize the press capability. That is, in the present embodiment, the space on the rear side of the bearing plate 12 is the accommodating space 60 of the hollow servomotor 6 in the box-shaped portion at the top of the main body frame 2. A different number of hollow servomotors 6 corresponding to the press capacity are accommodated in the accommodating space 60 (two in FIG. 2 of this embodiment). The hollow servomotors 6 to be accommodated have the same specifications such as output, torque, and rated rotational speed.

  Such a hollow servomotor 6 includes a magnet 61 fixed on the eccentric shaft 41 side and a coil 62 disposed so as to face the magnet 61, and is inserted through the eccentric shaft 41. In the hollow motor 6, the eccentric shaft 41 side on which the magnet 61 is provided functions as a rotor, and the coil 62 side functions as a stator. An encoder 63 is provided at the rear end of the eccentric shaft 41, and a rotation angle signal output from the encoder 63 is used for driving control of the hollow servomotor 6.

  Here, the bearing plates 11, 12, etc., that support the eccentric shaft 41 are provided so as to be split up and down, or are provided detachably with respect to the main body frame 2. The bearing plate 13 can also be divided into upper and lower parts, can be attached to and detached from the main body frame 2, and can be erected with its position changed. The eccentric shaft 41 can be easily replaced by dividing the bearing plates 11 to 13 or by detaching them from the main body frame 2.

  Then, by changing the standing position of the bearing plate 13, it is possible to replace the eccentric shaft 41 with a different length on the rear side. At this time, depending on the length of the eccentric shaft 41, different numbers of hollow servomotors 6 are set, and the press capacity can be easily changed by changing the number of eccentric shafts 41 and hollow servomotors 6. can do.

  FIG. 3 shows an example in which another eccentric shaft 41A that is longer than the eccentric shaft 41 shown in FIG. 2 is used as the eccentric shaft 41, for example. In such an electric servo press 1, the bearing plate 13 that supports the eccentric shaft 41 </ b> A is provided as a hollow servo motor 6 that is shifted to the rear side by one machine.

  Accordingly, the number of the hollow servo motors 6 used in the preliminarily provided housing space 60 is three, and a larger press capacity is realized. The added hollow servo motor 6 is attached to a mounting portion provided in advance on the horizontal support plate 25.

  Such an eccentric shaft 41A may be incorporated from the beginning at the manufacturing factory of the electric servo press 1, and in the electric servo press 1 already installed in the press line, it is replaced in the middle to change the press capability. Also good.

  In addition, a single hollow servomotor 6 may be used by using a shorter eccentric shaft 41, or four or more hollow servomotors 6 may be used by using a longer eccentric shaft 41. An appropriate number of attachments can be selected, and the eccentric shaft 41 having a length corresponding to the number of attachments can be used.

The movement of the electric servo press 1 will be described.
When the eccentric shaft 41 is rotated in a predetermined forward rotation direction by supplying an electric current to the hollow servo motor 6, the eccentric drum 44 rotates integrally with the slider crank 42, and the slider crank 42 swings in the reverse rotation direction. Along with the swing, the slider connecting rod 43 descends and the slide 5 descends.

  Further, when the eccentric shaft 41 rotates beyond the predetermined rotation angle toward the rotation angle of 180 degrees, the slider crank 42 swings forward so that it returns, and along with this swing, the slider connecting rod 43 and the slide 5 are further lowered. Thereafter, when the rotation angle of the eccentric shaft 41 reaches 180 degrees and the slider crank 42 returns to the initial position, the slide 5 reaches the bottom dead center (the position indicated by the solid line in FIG. 1).

  When the eccentric shaft 41 is continuously rotated to the forward rotation side, the slider crank 42 swings again to the reverse rotation side, and the slider connecting rod 43 and the slide 5 start to rise. When the rotation angle of the eccentric shaft 41 exceeds a predetermined angle and reaches 360 degrees, the slider crank 42 turns to the normal rotation side and swings, and the slider connecting rod 43 and the slide 5 further rise. When the rotation angle of the eccentric shaft 41 reaches 360 degrees and makes one rotation, the slider connecting rod 43 returns to the starting position again, and the slide 5 returns to the top dead center (the position of the two-dot chain line in FIG. 1).

  In such an electric servo press 1, as described above, it is possible to perform press processing for one stroke by rotating the eccentric shaft 41 once. Further, in the conventional press having the toggle link mechanism, the so-called pendulum operation in which the slide is moved up and down with a small stroke across the bottom dead center is impossible in structure, but according to the electric servo press 1, By switching forward and reverse of the eccentric shaft 41 so that the slide 5 repeats vertical movement across the bottom dead center, the pendulum operation of the slide 5 can be realized, and more various processing methods can be realized.

[Second Embodiment]
In FIG. 4, as the electric servo press 1 according to the second embodiment of the present invention, the eccentric shaft 41A shown in FIG. 3 of the first embodiment is used, and the number of mounting of the hollow servo motors 6 is two. An example is shown. Other configurations are the same as those of the electric servo press 1 of FIG.

  In this embodiment, the long eccentric shaft 41A is used in advance so that the number of hollow servomotors 6 can be changed without exchanging the eccentric shaft 41, so that the eccentric shaft 41 need not be replaced. This makes it easier to change the ability. Of course, it is possible to change the hollow servomotor 6 to one.

  That is, on the support plate 25 side, the entire hollow servomotor 6 is detachable according to the press capability, and in the eccentric shaft 41, in particular, the magnet 61 of the hollow servomotor 6 is detachable. Is provided.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the above embodiment, the slider connecting rod 43 is connected to the plunger 51 via the wrist pin 49. However, since the slider connecting rod 43 does not slide around the wrist pin 49, the slider connecting rod and the plunger are integrated. It may be provided as a thing.

In the embodiment, the C-shaped frame is adopted as the main body frame 2, but an O-shaped frame may be adopted by using a plate-shaped frame member having no opening.
In the above-described embodiment, the slide 5 is operated by the single slider crank mechanism 4. However, a plurality of slider crank mechanisms 4 may be employed when the larger slide 5 is moved up and down.

  In the above embodiment, the die height is adjusted by the worm gear having the screw shaft 53 screwed to the plunger 51 and the worm wheel 54 meshing with the screw shaft 53, but between the slider crank 42 and the slider connecting rod 43. A structure in which an eccentric ring for slide adjustment is interposed may be used. In such a case, the slide 5 does not require a die height adjusting mechanism, and therefore the slide 5 can be integrally provided on the lower side of the slider connecting rod 43.

  In the above embodiment, the hollow servomotor 6 is juxtaposed on the support plate 25, but the frontmost hollow servomotor 6 is fixed to the vertical surface of the bearing plate 12, and the hollow servomotor 6 is next to the hollow servomotor 6. An installation structure in which the hollow servomotor 6 is directly attached may be employed.

  In the above-described embodiment, all the hollow servomotors 6 have the same specifications. However, as long as there are not so many types, the present invention includes the case where a plurality of types of hollow servomotors 6 having different specifications are prepared. It is.

  The present invention can be used as a general-purpose electric servo press systematized according to the press capability, and also as a retrofit-compatible electric servo press.

  DESCRIPTION OF SYMBOLS 1 ... Electric servo press, 4 ... Slider crank mechanism, 5 ... Slide, 6 ... Hollow servo motor, 41, 41A ... Exen shaft, 42 ... Slider crank, 43 ... Slider connecting rod, 49 ... Wrist pin, 60 ... Accommodating space.

Claims (4)

A body frame composed of a plurality of plate-like frame members;
A bolster installed on the lower front surface of the main body frame;
A slider crank mechanism provided at an upper portion of the main body frame;
A slide connected to the slider crank mechanism to be movable up and down;
A hollow servo motor that drives the slider crank mechanism;
The slider crank mechanism is
An eccentric shaft that is inserted through the hollow servomotor and driven by the hollow servomotor ;
A slider crank that is slidably provided on the outer periphery of the eccentric shaft, and the outer periphery is eccentric with respect to the inner periphery;
A slider connecting rod which is slidably provided on the outer periphery of the slider crank and which is movable up and down ;
The upper part of the main body frame is formed in a box shape by the plurality of frame members, and is provided with a storage space for storing a different number of hollow servomotors according to the press capacity ,
The electric servo press characterized in that the eccentric shaft is replaced with one having a length corresponding to the number of the hollow servo motors . A body frame composed of a plurality of plate-like frame members;
A bolster installed on the lower front surface of the main body frame;
A slider crank mechanism provided at an upper portion of the main body frame;
A slide connected to the slider crank mechanism to be movable up and down;
A hollow servo motor that drives the slider crank mechanism;
The slider crank mechanism is
An eccentric shaft that is inserted through the hollow servomotor and driven by the hollow servomotor ;
A slider crank that is slidably provided on the outer periphery of the eccentric shaft, and the outer periphery is eccentric with respect to the inner periphery;
A slider connecting rod which is slidably provided on the outer periphery of the slider crank and which is movable up and down ;
The upper part of the main body frame is formed in a box shape by the plurality of frame members, and is provided with a storage space for storing a different number of hollow servomotors according to the press capacity ,
The eccentric shaft is supported by a bearing plate erected on the main body frame and can be exchanged for a length corresponding to the number of the hollow servo motors.
The electric servo press characterized in that the bearing plate has a standing position changed according to the length of the eccentric shaft . In the electric servo press according to claim 1 or 2 ,
The electric servo press characterized in that when a plurality of hollow servomotors are accommodated in the accommodating space, these hollow servomotors have the same specifications. In the electric servo press according to any one of claims 1 to 3 ,
The electric servo press, wherein the slide is connected to the slider connecting rod via a wrist pin.

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