JPH0528598U - Gravity balancer for press machine - Google Patents

Abstract

(57) [Summary] [Purpose] Perform vertical balance smoothly while absorbing horizontal component force. [Structure] The guide mechanism 50 (50A, 50B) is provided with a reversing lever 51 (51A, 51B) and an upper / lower link rod (5).
4, 57) and is configured to vertically guide the second weight (21) and to absorb the horizontal component force by the frame (1) to absorb it.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a weight balance device for a press machine including a weight type horizontal balance part and a vertical balance part.

[0002]

[Prior Art]

 In a press machine in which the eccentric shaft of the crankshaft and the slide are connected by a connecting rod, and the slide reciprocates vertically as the crankshaft rotates, a gravity balance device having a weight-type horizontal balance part and a vertical balance part is used. Is provided.

The horizontal balancing portion (10) is composed of so-called horizontal balancing weights (10), and as shown in FIG. 4, the crankshaft 2 has an eccentric shaft shape and is opposite in position to the slide driving eccentric shaft portion 3. Is integrally molded into. That is, as shown in FIG. 4, the distance from the central axis Z of the crankshaft (2) to the central axis Z1 of the eccentric shaft portion 3 is e1, the distance to the central axis Z2 of the first weight 10 is e2, and the eccentricity is When the weight of the shaft portion 3 is W1 and the weight of the first weight is W2, W1 · e1 = W2 · e2 is formed in the horizontal direction about the axis Z.

On the other hand, since the vertical balance unit 20 is for vertically balancing the slide 6, the vertical balance unit 20 is formed to reciprocate in the vertical direction with a phase difference of 180 degrees with respect to the slide 6. That is, the vertical balancing portion 20 is composed of a second weight 21 guided by the guide mechanism (41) so as to be vertically reciprocally movable, and a drive mechanism 31 for driving the second weight 21.

As shown in FIG. 4, the drive mechanism 31 includes a journal pin 25 fitted into the second weight 21 and a drive rod 32 whose ends are rotatably supported by the first weight 10. The second weight 21, like the slide 6, is vertically reciprocated about a vertical axis Y passing through the axis Z of the crankshaft 2. Therefore, since the eccentric shaft portion 3 and the first weight (eccentric shaft portion) 10 have opposite directions, the second weight 21 is vertically reciprocated with a phase difference of 180 degrees with respect to the slide 6, so that the vertical weight is vertical. Be balanced.

Here, in the conventional guide mechanism (41), a plurality of (two in the figure) bushes (holes) 22A, 22B are provided in the second weight 20 as shown by the solid line in FIG. It is configured to be fitted to a plurality (two) of guide rods 42A and 42B provided.

If the inner diameters of the bushes 22A and 22B are d2 and the outer diameters of the guide rods 42A and 42B are d1, the difference between the inner and outer diameters, that is, the clearance (d2-d1) can be reduced. It can move up and down smoothly without rattling. Increasing the pitch P of each of the guide rods 42A and 42B has the same effect. The reason why the plurality of guide rods (42A, 42B) are provided is that the second weight 21 is also configured to prevent rotation within the plane.

[0008]

[Problems to be solved by the device]

 However, in the above-described conventional structure, the horizontal component force from the drive rod 32 must be received by the guide mechanism 41. Therefore, the clearance (d1-d2) is enlarged depending on the ratio of the pitch P of the guide rods 42A and 42B and the guide length (the length of the bushes 22A and 22B) that cannot be formed uniformly due to diversification. As shown by the dotted line and the one-dot chain line in Fig. 5, tilt and shake occur, which deteriorates the product accuracy. Smooth equilibrium is disturbed, causing vibration and noise. Further, if the deterioration deteriorates, a situation may occur in which the vertical reciprocating movement of the second weight 21 is disturbed.

On the other hand, when a plurality of guide rods 42A and 42B are used, the clearance (d2-d1) must be increased in order to absorb the thermal expansion with the second weight 21. In other words, the clearance has to be increased more and more with the increase in size of the press machine, resulting in the above-mentioned problems from the beginning, and it is becoming difficult to use it especially in high-speed press machines.

An object of the present invention is to eliminate the enlargement of the clearance by the multiple guide rod method and to absorb the horizontal component force from the drive mechanism to stabilize the smooth gravity balance and to perform a highly accurate press machine operation. To provide a gravity balance device.

[0011]

[Means for Solving the Problems]

 The present invention includes a horizontal balancing portion composed of an eccentric shaft-shaped first weight, which is attached to a crankshaft so as to face an eccentric shaft portion that vertically reciprocates a slide via a connecting rod, and is vertically movable by a guide mechanism. A gravity balance device for a press machine comprising a guided second weight, a vertical balance portion formed by including a journal pin inserted into the second weight, and a drive rod connecting the first weight, The guide mechanism includes a reversing lever mounted on the journal pin so as to be rotatable relative to the journal pin, and a pair of both-end rotation supporting type link rods connecting the upper end and the lower end of the reversing lever to the frame. However, the effective lengths of both link rods are the same, and the distance between the rotation support part of the reversing lever of each link rod and the axis of the journal pin is the same. That it is configured to be absorbed in the horizontal direction component force induced from the driving force of the driving rod and, characterized.

[0012]

[Action]

 In the present invention having the above structure, when the drive rod forming the drive mechanism moves up (down) the second weight, a horizontal component force is generated between the second weight and the second weight due to the tilting of the drive rod. Therefore, the journal pin tries to move horizontally, but it cannot move because the upper and lower ends of the reversing lever are connected to the frame via the link guide. That is, the horizontal component force is received by the frame. Therefore, the concept of expanding the clearance in the case of the conventional guide rod system does not occur.

Further, since the effective lengths of the link rods are the same and the tip rotation support portions of the link rods and the journal pins are equidistant from each other, the reversing lever tilts but the axis line of the journal pin is tilted. Moves vertically. Therefore, the second weight can be smoothly vertically guided without tilting or swinging.

[0014]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. The gravity balancing device of the present press machine is shown in FIGS. In FIG. 1, reference numeral 1 denotes a frame that holds a crankshaft 2 in rotation, and a pair of connecting rods 4A and 4B are fitted on an eccentric shaft 3 that is integral with the crankshaft 2. The lower ends of the connecting rods 4A and 4B are rotatably supported by the slide 6 by pins 5A and 5B. Therefore, by rotating the crankshaft 2, the slide 6 can be reciprocated in the vertical direction.

Here, a first weight (eccentric shaft portion) 10 integrally formed with the crankshaft 2 in the opposite direction to the eccentric shaft portion 3 forms a horizontal balancing portion (10). The details are the same as in the conventional example (Fig. 4).

On the other hand, the vertical balance unit 20 is composed of a second weight 21, a drive mechanism 31, and a guide mechanism 50 (50A, 50B), as shown in FIGS. A journal pin 25 is fitted on the second weight 20.

The base end portion 33 of the drive rod 32 forming the drive mechanism 31 is fitted to the first weight 10 via the bush 34, and the tip end portion 35 is fitted to the journal pin 25 via the bush 36. There is. Therefore, when the crankshaft 2 is rotated, the drive mechanism 31 (32) can reciprocate the second weight 21 upward and downward with a phase difference of 180 degrees with respect to the slide 6.

As shown in FIGS. 1 and 2, one hole 23 is formed in the second weight 21, and a rotation stop pin 24 is inserted from the frame 1 into this hole 23. The idea is to prevent the second weight 21 from rotating within the plane (the plane of FIG. 2). Therefore, the clearance C may be extremely large as compared with the case of the conventional guide rod system.

Now, as shown in FIG. 3, the guide mechanism 50 (in this embodiment, a pair of left and right pair 50A and 50B is provided), which is a technical feature of the present invention, has a reversing lever 51A ( 51B) and upper (lower) link rods 54A (54B) and 57A (57B), which guide the journal pin 25 movably in the vertical axis Ya and Yb directions and also based on the tilting of the drive rod 32. The horizontal component force generated as a result can be absorbed by the frame 1 via the link rods 54 and 57.

That is, the reversing lever 51 A (51 B) is rotatably supported by the journal pin 25, the upper end portion 52 thereof is rotatably connected to the tip end portion 54 F of the upper link rod 54 by the pin 53, and the lower end portion 55 thereof. A pin 56 is rotationally connected to the tip 57F of the lower link rod 57. The base ends 54B and 57B of the link rods 54 and 57 are rotatably supported on the frame 1 by pins 59U and 59L as shown in FIGS.

Here, the distances between the pins 59U and 59L of the link rods 54 and 57 and the pins 53 and 56, that is, the effective lengths L1 and L2 are the same (L1 = L2) as shown in FIG. , 56 and the journal pin 25 have the same distances H1 and H2 (H1 = H2).

Therefore, when a pushing-up force in the N direction shown in FIG. 3 is applied from the driving rod 32, the upper link rod 54 moves the pin 59U counterclockwise and the lower link rod 57 moves the pin 59L. As it rotates clockwise around the center, the journal pin 25 (axis Q) moves to the position QH. That is, the axis Q moves on the vertical axis Ya (Yb) shown in FIG. 1 between the positions QH and QL.

The horizontal component force from the driving rod 32 applied to the journal pin 25 is absorbed by the frame 1 via the two link rods 54 and 57.

In the gravity balancing apparatus having such a configuration, both the horizontal balancing unit 10 and the vertical balancing unit 20 excluding the guide mechanisms 50A and 50B work in the same manner as in the conventional example described with reference to FIG. At this time, the horizontal component force applied to the second weight 21 of the vertical balance portion 20 is absorbed by the frame 1 via the link rods 54 and 57 of the guide mechanism 50A (50B). The journal pin 25 (axis Q) moves on the vertical axes Ya and Yb by the action of the guide mechanism 50A (51, 54, 57) [50B]. That is, the second weight 21 can be vertically reciprocated vertically without tilting or swinging.

According to this embodiment, however, the guide mechanism 50 (50A) is composed of the reversing lever 51 and the upper and lower link bars 54 and 57, and the second weight 21 (journal pin 25) is always kept. Since the horizontal force component transmitted from the driving rod 32 is received by the frame 1 while being held on the vertical axis lines Ya and Yb, the problem of increasing the clearance between the conventional guide mechanism 40 and the guide rods 42A and 42B is eliminated. The vertical equilibrium action is always smooth and high precision press working is possible. It can also be applied as is to high-speed press machines.

Further, since the guide mechanism 50 is provided on both sides (50A, 50B) of the second weight 21, a smoother vertical balance can be ensured and the horizontal component force is applied to the frame 1 at a plurality of points. Since they can be held, the link rods 54, 57, etc. can be downsized.

Further, it is not necessary to provide the second weight 21 with a plurality of guide holes (bushings 22A and 22B) of the conventional example, and the clear run holding adjustment with the plurality of guide rods 42A and 42B is not necessary. Therefore, the assembly and adjustment are easy and the cost can be reduced.

Furthermore, there is no room for the problem of thermal expansion of the second weight 21 in the case of the conventional example, and thermal contraction of the second weight 21 is freely allowed on the journal pin 25.

In the above embodiment, the guide mechanism 50 is provided on each side of the second weight 21 as a pair of two sets 50A, 50B, but this may be implemented by one set. For example, it may be provided between the connecting rods 4A and 4B.

[0030]

[Effect of the device]

 As described above, according to the present invention, in the gravity balance device of the press machine formed of the horizontal balance part and the vertical balance part having the second weight, the guide mechanism, and the drive mechanism, the guide mechanism is provided with the reversing lever and the upper and lower parts. It is composed of a link rod and is configured to guide the second weight vertically and to absorb the horizontal component force by the frame to absorb it. Therefore, the guide rod system can prevent the second weight from tilting, swinging or thermally expanding. It has the excellent effects of being able to eliminate defects, being easy to assemble and adjust, being compact and low-cost, being able to operate smoothly even on high-speed press machines, and being capable of high-precision press working.

[Brief description of drawings]

FIG. 1 is a front sectional view showing an embodiment of the present invention.

FIG. 2 is likewise a plan view based on the line of arrow − in FIG.

FIG. 3 is also a side view based on the arrow line in FIG.

FIG. 4 is a diagram for explaining the principle of horizontal balancing and vertical balancing of the present invention and the conventional example.

FIG. 5 is a diagram for explaining a problem of a conventional example.

[Explanation of symbols]

 1 frame 2 crankshaft 3 eccentric shaft part 4, 4A, 4B connecting rod 6 slide 10 horizontal balance part (first weight) 20 vertical balance part 21 second weight 22A, 22B bush 23 hole 24 whirl-stop pin 25 journal pin 31 drive mechanism 32 drive rod 41 conventional guide mechanism 42A, 42B guide rod 50, 50A, 50B guide mechanism 51A, 51B reversing lever 52 upper end portion 53 pin (rotation support portion) 54 upper link rod 54B base end portion 54F tip end portion 55 lower end portion 56 Pin (rotary support part) 57 Lower link rod 57B Base end part 57F Tip part 59U, 59L Pin

Claims (1)

[Scope of utility model registration request] 1. A horizontal balancing portion composed of an eccentric shaft-shaped first weight mounted on a crankshaft so as to face an eccentric shaft portion for vertically reciprocating a slide via a connecting rod, and vertically movable by a guide mechanism. In a gravity balance device for a press machine, which comprises a vertical weight formed by including a second weight guided to the second weight, a journal pin fitted into the second weight, and a drive rod connecting the first weight, The guide mechanism includes a reversing lever mounted on the journal pin so as to be rotatable relative to each other, and a pair of both-end rotation-supporting link rods connecting the upper end and the lower end of the reversing lever to the frame, The effective lengths of both link rods are the same, and the distances between the rotation support portions of the reversing levers of the link rods and the shaft center of the journal pin are the same. That it is absorbed configured to be able to horizontal component force induced from the driving force of the driving rod Te, gravity balancing device for a press machine according to claim.