KR20030025803A - Dynamic balancer for a press - Google Patents

Abstract

PURPOSE: To provide a dynamic balancer device for press machine better adapted to speeding up a press machine as well as allowing cost reduction by minimizing the number of parts. CONSTITUTION: The dynamic balancer device 220 installed the upper side of a drive mechanism section 210 is provided with a balancer weight 223. The balancer weight 223 is rotatably formed with its one end pivoted by a support point pin 225, and its center of gravity is located close to a plumb line passing through the center of gravity on a slide 104. Therefore an inertial force generated by the vertical motion of the slide 104 can be balanced out despite the swing motion of the balancer weight 223. Additionally the number of connecting rods can be reduced than before, and the member of connecting rod for slide can be the same member of the balancer weight.

Description

Dynamic balancing device for presses {DYNAMIC BALANCER FOR A PRESS}

Technical Field

The present invention relates to a dynamic balancer for canceling the inertial forces generated by the vertical reciprocating motion of a press slide.

Prior art

As the slides of the press reciprocate vertically, the combined inertial forces cause vibrations of the press that depend on the size (mass) of the slides, the number of strokes (strokes per minute (spm)), etc. Can have In order to prevent this, it has been customary to use a dynamic balancing device (DB) having a mass approximately equal to the mass of the slide and operating in the opposite way.

1 shows a dynamic balancing device according to the prior art. In FIG. 1, the frame of the press 100 comprises a crown 101, a bed 103, four pillars 102 and a tie rod (not shown), the tie rod being a crown ( 101, through the column 102 and the bed 103 to tie them together. A slide 104 is provided below the crown 101 (above the bed 103) which can be reciprocated in the vertical direction because it is guided along the guide post 105. The bolster 106 is secured to the top surface of the bed 103 facing the bottom surface of the slide 104. The bottom die (not shown) of the press die is fixed to the top surface of the bolster 106, while the top die is fixed to the bottom surface of the slide 104. In the press 100, the workpiece is processed (pressurized) by the die (upper die and lower die) not shown in the figure as the slide 104 performs a vertical stroke.

The vertical stroke of the slide 104 is driven by the drive mechanism 110 embedded in the crown 101. The drive mechanism 110 is provided with a crankshaft 111 rotatably supported by the bosses 112a and 112b. The flywheel 113 is fixed to the right end of the crankshaft 111. The flywheel 113 is driven by a motor (not shown) which causes rotation, while the crankshaft is driven by a clutch-and-brake device 114 in which the rotational energy of the flywheel is provided on the flywheel 113. Is passed to 111.

The slide driving eccentric portion 111a is provided in the middle portion of the crankshaft 111. The end of the connecting rod 115 having a larger size is rotatably connected to the slide driving eccentric 111a by the bushing 116. On the other hand, the plunger 108 is provided on the slide 104 by the die height adjusting device 107 and guided by the plunger guide 109 freely to perform a stroke in the vertical direction. The end of the connecting rod 115 having a smaller size is connected to the plunger 108.

With respect to the height adjusting device 107, the threaded portion 108a at the end of the bottom of the plunger 108 meshes with the inner circumference of the worm wheel 107a, while the worm wheel 107a can rotate freely in the horizontal plane, The retainer 107c can be held in place. The outer circumference of the worm wheel 107a is engaged with the worm shaft 107b. The worm shaft 107b is driven to rotate by a motor (not shown). Therefore, when the worm shaft 107b rotates to drive the worm wheel 107a, the slide 104 (worm wheel 107a) moves up and down relative to the plunger 108 (screw portion 108a). Thus, the height of the die (denoted by DH in FIG. 1) is adjusted.

The driving device 110 is provided with a dynamic balancing device 120. The dynamic driver 120 is provided with DB (dynamic balancing device) driving eccentric portions 111b and 111c located next to the slide driving eccentric portion 111a on the crankshaft 111. The DB driving eccentric portions 111b and 111c are provided in phases opposite to the slide driving eccentric portions 111a. Large end portions of the DB connecting rods 121a and 121b are rotatably connected to the DB driving eccentric portions 111b and 111c by bushings 122a and 122b. On the other hand, the balance weight 123 is provided on the dynamic balancing device 120 (drive mechanism 110). The counterweight 123 is guided to move up and down by the guide pin 124. The connecting pin 125 connects the small end of the DB connecting rod 121 and the balance weight 123. The mass of the counterweight 123 is approximately equal to the total mass of the slide 104 and all members (such as the die height adjusting device 107) attached to the slide 104.

The press 100 (drive mechanism 110, dynamic balancing device 120, etc.) configured as described above generates the vertical stroke of the counterweight 123 opposite to the vertical stroke of the slide 104. That is, since the counterweight 123 has approximately the same mass as the slide 104 and operates on the opposite side of the slide 104, the inertial force generated by the vertical stroke of the slide 104 causes the counterweight 123 to vertically stroke. Offset by the inertial forces generated by

The prior art dynamic balancer has several disadvantages. In the case of prior art presses, for example, despite the fact that it is a single point press, three points of the crank must have an eccentric. Such a crankshaft with three eccentrics is difficult to manufacture (and perform machining) and expensive to manufacture. Moreover, since it has DB driving eccentrics on both sides of the slide driving eccentric, the large end of the connecting rod (slide driving eccentric) connected to the plunger (slide) should be made larger than the DB driving eccentric. As the diameter of the large end (slide driving eccentric) bore increases, the speed in the circumferential direction of the bore increases. This, in turn, results in temperature rise and lubrication breakdown in certain areas, adversely affecting the increase in the number of slide strokes per minute. One alternative to avoid increasing the large end of the connecting rod (slide driving eccentric) is to construct the large end of the connecting rod with a divided structure, but this causes an increase in manufacturing cost and makes the press more heavy.

It is an object of the present invention to provide a dynamic balancing device for presses that is light and suitable for reducing manufacturing costs, such as increasing the working speed of the press and reducing costs by, for example, reducing the number of components.

A DB driving eccentric mounted on the crankshaft to operate in an opposite phase to the slide driving eccentric; And a DB connecting rod for connecting to the DB driving eccentric on its large end and connecting to a counterweight on its small end, wherein the balancing is its work. It can be swiveled about a pivot provided on the end, and formed in such a way that the center of gravity of the counterweight is located on a plumb line that approximately passes through the center of gravity of the slide.

The configuration of this dynamic balancing device requires only one DB driving eccentric and one slide driving eccentric on one crankshaft. The result of this configuration is that the number of connecting rods (DB connecting rods) to be connected to the counterweight is reduced from two to one. The counterweight is formed to be pivotable and includes various members (hardware) (pivot pins, etc.) for the purpose, but the important thing is that the counterweight guide device and the like are eliminated, and as a whole, the number of parts and the manufacture of the entire dynamic balancing device The cost is reduced.

Furthermore, since there is no eccentric on one side of the crankshaft, the larger end of the connecting rod is divided by increasing the diameter of the slide driving eccentric or considering the assembly of the connecting rod connected to the slide on the crank shaft (slide driving eccentric). There is no need to do it. Since it is not necessary to increase the diameter of the slide driving eccentric, it is very advantageous to increase the working speed of the press, and since it is not necessary to divide it, the press weight can be reduced.

Even if the counterweight is turning, the center of gravity of the counterweight is always approximately in line with the vertical line passing through the center of gravity of the slide. As a result, the inertia force of the slide and the inertia force of the counterweight cancel each other, thus providing the advantage of suppressing the vibration of the press due to the stroke of the slide as in the prior art.

Therefore, the present dynamic balancing device not only reduces the production cost of the dynamic balancing device (press) compared to the press of the prior art, but also provides a dynamic balancing device for presses suitable for increasing the working speed of the press and reducing the weight of the press. Can be.

In another aspect, the present dynamic balancing device includes a DB connecting rod, which is the same member as the connecting rod for driving the slide. This device enables the connecting rod connected to the slide to share a common component with the connecting rod connected to the counterweight. Sharing parts can reduce parts manufacturing costs due to the effect of mass production. Therefore, such a configuration can provide a dynamic balancing device for a press that not only lowers the manufacturing cost but also realizes the above-mentioned advantages.

1 is a front view of a conventional press,

2 is a front view of a press according to the first embodiment,

3 is a partial plan view of the press of FIG. 2, illustrating a dynamic balancing device, FIG.

4 is a partially enlarged cross-sectional view of the press of FIG. 2, illustrating a dynamic balancing device;

5 is a plan view of a dynamic balancing device according to a second embodiment for use in a press, such as the press of FIG.

6 is an enlarged cross-sectional view of the dynamic balancing device of FIG.

2 to 4 illustrate the first embodiment. In order to simplify the description and omit the omission, parts and parts of the present press which are similar to the conventional press 100 shown in FIG. 1 according to the prior art are denoted by the same reference numerals. 2 is an overall front view of a press 200 according to the first embodiment of the present invention. 3 is a plan view of the dynamic balancing device shown in more detail in FIG.

2 to 4, the crankshaft 211 of the drive mechanism 210 is provided with a slide driving eccentric portion 211a. The large end of the connecting rod 212 is connected to the slide driving eccentric 211a by the bushing 213. The dynamic balancing device 220 is provided on the crown 101 (drive mechanism unit 210). The dynamic balancing device 220 is provided with a DB driving eccentric portion 211b on the crank shaft 211 opposite to the slide driving eccentric portion 211a on the crank shaft 211 adjacent to the slide driving eccentric portion 211a. do. The large end of the DB connecting rod 221 is rotatably connected to the DB driving eccentric 211b by the bushing 222.

The counterweight 223 is provided on the dynamic balancing device 220 (crown 101). In addition, the bracket 224 is fixed on the left side of the inner plate 101a of the left side of the crown 101, the pivot pin 225 is fixed to the bracket 224. The counterweight 223 is slidably connected to the pivot 225 by a bushing 224. That is, the counterweight 223 is supported by the pivot pin 225 (bracket 224) so as to pivot about the pivot pin. The balance weight 223 configured as described above is connected to the small end of the DB connecting rod.

As a result, the dynamic balancing device 220 performs a swiveling action pivoted up and down by the pivot pin 225 in a phase opposite to the slide 104 by pivoting about the pivot pin 205. do.

The dynamic balancing device 223 has its mass approximately equal to the mass of the slide 104 or the like (including the die height adjusting device 107, etc.), and the position of its center of gravity on the horizontal plane (xy plane) is horizontal. It is formed in substantially the same manner as the uncentered center of the slide 104 or the like on the (xy plane). That is, the center of gravity of the balance weight 223 is located on a vertical line passing through the center of gravity of the members (slide 104, etc.) that the inertial force is offset. The center of gravity of the slide 104 or the like is generally the center of the press. Thus, the center of gravity of the counterweight 223 is arranged to be at point G shown in FIGS. 3 and 4. As a result, the inertial forces generated by the vertical stroke of the slide 104 cancel out as the counterweight 223 pivots out of phase with the vertical stroke of the slide 104.

By configuring the dynamic balancing device 220 in this manner, only two eccentric parts are needed on the crankshaft 211. Therefore, the connecting rod 212 connected with the slide 104 can be assembled from the side (right side in the drawing) in which the DB driving eccentric portion 211b is not provided. In the prior art dynamic balancing device, since there is a DB driving eccentric on both sides of the slide driving eccentric, the large end of the connecting rod 212 in order to enlarge the diameter of the slide driving eccentric or to assemble the connecting rod 212. While the parts need to be divided, in the present embodiment, no special device is required, and the slide driving eccentric portion 211a can have the same diameter as the DB driving eccentric portion 211b. That is, the present embodiment can reduce the diameter of the slide driving eccentric portion and make the connecting rod 212 lighter than the prior art design, thereby providing a dynamic balancing device suitable for presses operating at higher working speeds. .

Moreover, since the same diameter can be used for the DB driving eccentric portion 211b and the slide driving eccentric portion 211a, the DB driving rod 221 for the DB driving can share a common part with the connecting rod 212. Part sharing can reduce manufacturing costs.

A second embodiment having such an effect is shown in FIGS. 5 and 6. FIG. 5 corresponds to a plan view of the dynamic balancing device of FIG. 6, and FIG. 6 illustrates an enlarged cross section of the press to illustrate the dynamic balancing device of the present embodiment. Common parts and regions in FIG. 5 are indicated by the same reference numerals as in the previous embodiment in order to simplify or omit unnecessary description.

In this embodiment, the bracket 224 (pivot pin 225) is provided on the front plate 101c of the crown 101. The operation is similar to that of the first embodiment (FIGS. 2 to 4), except that the pivot for pivoting the counterweight 323 is made in front of the press 300. According to the second embodiment, the connecting rod connected to the slide can share the same parts as the DB connecting rod connected to the counterweight, thereby realizing additional cost reduction through mass production of common components and the first embodiment. The advantages of the example can be realized.

The device overcomes the disadvantages associated with conventional devices and provides several advantages not available in conventional structures. For example, according to the present apparatus, the same diameter can be used for both the slide driving eccentric portion and the DB driving eccentric portion, so that the diameter of the slide driving eccentric portion can be reduced. This results in a reduction in the circumferential speed of the slide driving eccentric, which brings a very good advantage in terms of temperature rise and lubrication problems when trying to increase the working speed of the press (slide). Therefore, the present invention provides a dynamic balancing device suitable for faster operation of a press. Furthermore, since the number of eccentrics is reduced to two from three in the prior art, the manufacturing cost for the crankshaft can be reduced. The number of DB connecting rods is also reduced from two to one, further reducing the production cost of the press.

While the invention has been shown and described in detail with reference to preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Claims (15)

A dynamic balancing device driving eccentric unit mounted on the crankshaft and operating in an opposite phase to the slide driving eccentric unit, which is also mounted on the crankshaft; And In a dynamic balancing device for a press comprising a dynamic balancing device connecting rod for connecting a first end to the eccentric for driving the dynamic balancing device, and for connecting the opposite second end to a counterweight. The counterweight can pivot about a pivot provided at one end thereof and is formed in such a way as to have a center of gravity of the counterweight located approximately on a plumb line passing through the center of gravity of the slide. Dynamic balancing device. The method of claim 1, And a bracket coupled to the support structure, wherein the bracket has a pivot pin coupled thereto, the balance being supported by the fiber pin to permit pivot movement about the pivot pin. The method of claim 1, Dynamic balancing device, characterized in that the first end has a larger dimension than the second end. The method of claim 1, And the eccentric portion for driving the dynamic balancing device and the slide eccentric portion for mounting on the crankshaft. The method of claim 1, The dynamic balancing device connecting rod is a dynamic balancing device, characterized in that the balance is connected to the counterweight at the opposite end of the one end pivoting about the pivot. The method of claim 1, And the diameter of the slide driving eccentric portion is substantially the same as the diameter of the dynamic balancing device driving eccentric portion. The method of claim 1, And the counterweight is pivoted in such a way as to cancel the reciprocating motion of the slide such that the center of gravity of the counterweight is substantially aligned with the axis passing through the center of gravity of the slide. The method of claim 1, The dynamic balancing device connecting rod is a dynamic balancing device, characterized in that the same member as the connecting rod for driving the slide. A dynamic balancing device driving eccentric unit mounted on the crankshaft and operating in an opposite phase to the slide driving eccentric unit, which is also mounted on the crankshaft; And In a dynamic balancing device for a press comprising a dynamic balancing device connecting rod for connecting a first end to the eccentric for driving the dynamic balancing device, and for connecting the opposite second end to a counterweight. The counterweight can pivot about a pivot provided at one end thereof, and the dynamic balancing device cancels the inertia force generated by the vertical reciprocating motion of the slide and cancels its horizontal plane (xy plane). Dynamic balancing device, characterized in that the position of the center of gravity of the counterweight according to the configuration and arrangement is approximately equal to the center of gravity of the slide along its horizontal plane (xy plane). The method of claim 9, And a bracket coupled to the support structure, wherein the bracket has a pivot pin coupled thereto, the balance being supported by the fiber pin to permit pivot movement about the pivot pin. The method of claim 9, Dynamic balancing device, characterized in that the first end has a larger dimension than the second end. The method of claim 9, And the eccentric portion for driving the dynamic balancing device and the slide eccentric portion for mounting on the crankshaft. The method of claim 9, The dynamic balancing device connecting rod is a dynamic balancing device, characterized in that the balance is connected to the counterweight at the opposite end of the one end pivoting about the pivot. The method of claim 9, And the diameter of the slide driving eccentric portion is substantially the same as the diameter of the dynamic balancing device driving eccentric portion. The method of claim 9, The dynamic balancing device connecting rod is a dynamic balancing device, characterized in that the same member as the connecting rod for driving the slide.