JP2002144094A - Press machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the stroke length of a slide changeable by using a bell crank and to enable a higher speed operation. SOLUTION: The press machine includes a crank shaft 16 which is rotatably born at a frame 14 and a power transmission device 30 which transmits the rotating motion of the crank shaft to the slide 20. The power transmission device includes the bell crank 70 which is born at the frame oscilatably movable around the axis parallel to the axis of rotation of the crank shaft, a connecting member 72 which connects the bell crank and the slide so as to vertically move the slide by accompanying the oscillation motion of the bell crank, a connecting mechanism which is connected to the crank shaft, the bell crank and the slider so as to oscillate the bell crank by accompanying the rotation of the crank shaft and a position regulating mechanism 40 which regulates the position of the slider in a vertical direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press machine for converting a rotary motion of a crankshaft supported on a frame into a reciprocating motion and transmitting the reciprocating motion to a slide.

[0002]

2. Description of the Related Art One of the presses capable of adjusting the stroke length of a slide is disclosed in Japanese Patent Publication No. 7-5538.
There is a technique described in Japanese Patent Application Laid-Open No. 9-90. In this technology,
The rotational movement of the crankshaft is converted into a vertical movement of the slide by a toggle mechanism. Therefore, as compared with the crank press, the slide speed is greatly reduced near the bottom dead center. As a result, the slide stroke near the bottom dead center is long, but the slide stroke near the top dead center is short.

[0003]

However, in the above press machine, high-precision machining is possible because the stroke near the bottom dead center is long, but the stroke near the top dead center is short. The time allowed to transfer material into the mold is reduced, thereby hindering higher speeds for products that do not require very high precision. In a press machine using a toggle mechanism, a change in slide acceleration near the top dead center is large, which also hinders speeding up.

[0004] There is known a press machine which converts the rotational motion of a crankshaft into a vertical motion of a slide by a bell crank mechanism (for example, Japanese Patent Publication No. 7-114474). However, in this press machine, the stroke length of the slide cannot be changed.

An object of the present invention is to make it possible to change the stroke length of a slide using a bell crank and to make it possible to increase the speed.

[0006]

A press machine according to the present invention comprises:
It includes a crankshaft rotatably supported by a frame, and a power transmission device for transmitting the rotational motion of the crankshaft to a slide. The power transmission device includes: a bell crank supported on the frame so as to be swingable about an axis parallel to a rotation axis of the crankshaft; and a vertical movement of the slide along with the swing movement of the bell crank. A connecting member for connecting the bell crank and the slide so that the slider is disposed on the frame so as to be movable in a vertical direction, and the bell crank is swung with the rotation of the crank shaft. A connection mechanism connected to the crankshaft, the bell crank, and the slider; and a position adjustment mechanism that adjusts a position of the slider in a vertical direction.

When the position of the slide is changed by the position adjusting mechanism, the angular range of the swing motion of the bell crank is changed via the connecting mechanism connected to the slide, and the stroke length of the slide in the vertical direction is changed. Is done.

A press using a bell crank is
Compared with a press using a toggle mechanism, there is no large difference in the slide stroke near the bottom dead center and near the top dead center, so that the speed can be increased.

As a result, according to the present invention, the stroke length of the slide can be changed and the speed can be increased.

[0010] The press machine may further comprise a balancing device having a balancing weight disposed on the frame so that the bell crank can move up and down. It may include a connected balancing device. In this case, since the vertical movement of the slide and the balance weight is opposite to each other, the imbalance force caused by the vertical movement of the slide and the balance weight is canceled.

The balance weight is located above the crankshaft, the bell crank and the coupling mechanism and is reciprocally movable in the frame in the vertical direction. And a connecting body connected to the bell crank and connected to the counterweight at the upper end side.

The bell cranks have an angle with each other.
It has a T-shape with one arm, one arm being connected to the connection mechanism, the other arm being connected to the connection member, and the remaining arm being the counterbalance. It can be connected to a device.

[0013] The press machine may further include one or more weight guides for regulating the vertical movement of the counterweight in the vertical direction. By doing so, the reciprocating motion of the balance weight in the horizontal direction is prevented, so that the vibration of the press machine in the horizontal direction due to the reciprocation of the balance weight can be prevented.

The link mechanism is a link mechanism having a pair of links connected so as to bend and extend with the rotation of the crankshaft. One link is connected to the crankshaft and the other link is connected to the crankshaft. The link mechanism may include a link mechanism connected to the slide, and a link that swings the bell crank in accordance with the bending and extending movement of the link mechanism. In such a case, when the position of the slider is changed by the position adjusting mechanism, the bending angle range of both link pieces is changed, and the swing angle range of the bell crank is changed.

The power transmission device further includes a second bell crank supported on the frame so as to swing around an axis parallel to a rotation axis of the crank shaft;
A second connecting member for connecting the second bell crank and the slide so as to cause the slide to move up and down with the swinging motion of the bell crank; and connecting the second bell crank to the crankshaft. A second coupling mechanism coupled to the crankshaft, the second bell crank and the slider so as to swing with rotation, the coupling mechanism flexing and extending with rotation of the crankshaft; First and second link mechanisms each having a pair of links operatively connected, one link being commonly connected to the crankshaft and the other link being commonly connected to the slide; First and second link mechanisms, and first and second connections respectively corresponding to the first and second link mechanisms and individually corresponding to the bell crank. Each A link can include a first and a second connecting link swinging the bell crank corresponding with the bending and stretching motion of the corresponding link mechanism.

The position adjusting mechanism includes a bracket pivotally connected to the slider, and a disk-shaped bracket disposed on the frame so as to be rotatable around an axis extending in one direction and immovable in the one direction. It includes a rotating body and a rotating mechanism for rotating the rotating body. One of the bracket and the rotating body has a female screw hole, and the other can have a male screw portion screwed into the female screw hole. Thereby, the position of the slider in the one direction can be finely adjusted, so that the stroke curve of the slide and the instantaneous speed at each point of the vertical movement can be finely adjusted according to the type of press working.

The press may further include a second slider disposed on the frame so as to be vertically movable, the second slider being connected to the crankshaft and the connection mechanism.

[0018]

1 to 6, a press machine 10 includes a lower frame 12 on which a lower die is placed, and an upper frame 14 supported by the lower frame 12. As shown in FIG.
The crankshaft 16 is supported by the upper frame 14 so as to be rotatable about an axis extending in the horizontal direction, and receives rotation of a flywheel 18 shown in FIG. The flywheel 18 is rotated by a motor (not shown) such as an electric motor.

The so-called slide 20 for supporting the upper mold is:
It is assembled to a pair of connecting rods that penetrate the lower end of the upper frame 14 movably in the vertical direction, that is, the lower end of the plunger 22. Both plungers 22 are slide 2
0 extend from both ends in parallel upward and reciprocate up and down by the power transmission device 30 and a bell crank 70 described later with the rotational movement of the crankshaft 16. As a result, the slide 20 is reciprocated in the vertical direction.

The power transmission device 30 is vertically spaced apart from the connection 32 connected to the crankshaft 16 so as to be able to reciprocate up and down in the upper frame 14 and is pivotally movable to the connection 32 (that is, the connection 32 is pivotable). A pair of upper sliders 34 pivotally connected to each other, a pair of link mechanisms 36 that bend and extend following the reciprocating movement of the upper sliders 34 and in synchronism with each other, and the upper frame 14 so as to be vertically displaceable. And two link mechanisms 36
And a pair of lower sliders 38 pivotally connected to each other, and a position adjusting mechanism 40 for adjusting the positions of the lower sliders 38 in the vertical direction.

The connection 32 is pivotally connected to the eccentric portion of the crankshaft 16 and reciprocates up and down while swinging with the rotation of the crankshaft 16. The sliders 34 and 38 are received by guide portions 42 and 44 (see FIG. 3) formed on the upper frame 14 so as to be vertically movable.

The upper slider 34 reciprocates up and down following the reciprocation of the connection 32 to bend and extend both link mechanisms 36. The lower slider 38 reciprocates in the vertical direction following the bending and extending movements of both link mechanisms 36.

Each link mechanism 36 includes a pair of links 36.
a, 36b. Link 36 of each link mechanism 36
A and 36b are connected to each other by a pivot 46 at the lower end of the link 36a and the upper end of the link 36b so as to be bendable.

One link 36a of both link mechanisms 36
Are pivotally connected at an upper end to a connection 32 and an upper slider 34 by a common pivot 48. The other link 36b of both link mechanisms 36 is pivotally connected to the lower slider 38 at the lower end by a common pivot 50.

In the illustrated example, the pivots 48 and 50 are provided such that their pivot points coincide with an axis 52 (see FIG. 2) extending vertically through the center of rotation of the crankshaft 16. However, the pivots 48, 50 need not be so arranged.

In the illustrated example, the link 3 of the link mechanism 36
Although 6a is directly connected to the connection 32 and the upper slider 34, the link 36a of the link mechanism 36 may be connected to only one of the connection 32 and the upper slider 34.

The position adjusting mechanism 40 includes a bifurcated bracket 54 pivotally connected to the two links 36b and the slider 38 by a pivot 50, a male screw 56 extending downward from the bracket 54, and a worm screwed to the male screw. The worm wheel 58 includes a worm screw 60 that meshes with the worm wheel 58. Instead of using the bracket 54, the external thread 56 may be pivotally connected to the two links 36b and the lower slider 38 by the pivot 50.

The male screw 56 is connected to the bracket 54 so as not to rotate about the axis 52. The worm wheel 58 is supported by the supporting portions 62 and 64 of the upper frame 14 so as to be rotatable around the axis 52 and immovable in the vertical direction. The shaft of the worm screw 60 rotatably extends through the upper frame 14 and has a sprocket 66 at an end (see FIG. 6). The sprocket 66
It is rotated by a rotation mechanism (not shown) such as an electric motor.

When the sprocket 66 is rotated, the worm screw 60 is rotated, and the worm wheel 58 meshed with the worm screw 60 is rotated. Therefore, the male screw 56 screwed with the worm wheel 58 moves upward or downward. Then, the lower slider 38 is finally moved upward or downward. Therefore, the worm wheel 58 acts as a rotating body.

The power transmission device 30 also includes a link mechanism 3
6 and a pair of bell cranks 70 respectively supported on the frame 14 for swinging movement about an axis parallel to the rotation axis of the crankshaft 16, and bells individually corresponding to and corresponding to the bell cranks 70. The bell crank 70 is moved through the plunger 22 so that the slide 20 moves up and down with the swinging movement of the crank 70.
And a pair of connectors that respectively correspond to the set of the link mechanism 36 and the bell crank 70 and follow the bending / extending movement of the corresponding link mechanism 36 to swing the corresponding bell crank 70. Connecting link 7
4 is included.

One set of the bell crank 70, the connecting member 72, and the connecting link 74 corresponds to the one plunger 22 and the link mechanism 36, and is pivotally connected to the one plunger 22 and the link mechanism 36. The other set of the bell crank 70, the connecting member 72, and the connecting link 74 corresponds to the other plunger 22 and the link mechanism 36, and is pivotally connected to the other plunger 22 and the link mechanism 36.

Each bell crank 70 has a T-shape with three arms having the same angle (90 degrees in the illustrated example) with each other. It is pivotally assembled at the branch of the three arms.

Each of the bell cranks 70 has one arm connected to the link mechanism 36 by a connecting member 72, and the link mechanism 36 swings by bending and extending. The swing motion of each bell crank 70 is transmitted to the slide 20 so as to move the slide 20 up and down by a connection link 74 connected to another one arm.

The press 10 further includes a balancing device 80 for balancing an unbalanced force caused by the vertical movement of the slide 20.
including. The balancing device 80 includes a balancing weight 82 located above the crankshaft 16, both link mechanisms 36, and both bell cranks 70 and movably arranged in the upper frame 14 in the vertical direction. And a pair of connecting pieces or connecting bodies 86 individually corresponding to the bell crank 70.

Each link 86 is pivotally connected at its lower end to the corresponding arm of the bell crank 70 at a lower end by a horizontally extending pivot, and by a horizontally extending pivot at the upper end to a counterweight 82 at the upper end. Are connected pivotally. The reciprocating motion of the balance weight 82 may be limited in the vertical direction by using one or more weight guides 84.

The pivots, such as the pivots 46, 48, 50, etc., which pivotally connect or support a plurality of members, extend horizontally in parallel with the axis of rotation of the crankshaft 16. Therefore, the pivotal movement of the members interconnected by or supported by each pivot is a movement about an axis extending horizontally.

In the press machine 10, the upper slider 34
Is the connection 3 as the crankshaft 16 rotates.
2 is reciprocated in the up-down direction, thereby reciprocating in the same direction. On the other hand, the lower slider 38 is not moved unless the worm wheel 58 is rotated. Thus, the pivot 48 acts as a movable fulcrum of the link mechanism 36, and the pivot 50 acts as a fixed fulcrum of the link mechanism 36.

The rotation of the flywheel 18 corresponds to the crankshaft 1
6, the connection 32 and the slider 34 are reciprocated in the vertical direction with the rotation of the crankshaft 16, so that the two link mechanisms 36 are bent and extended in synchronization. As a result, both bell cranks 70 swing in synchronization, and as a result, the slide 20 reciprocates.

When the two bell cranks 70 swing, the balance weight 82 follows the swing motion of the two bell cranks 70,
Moved up and down. The reciprocating movement of the balance weight 82 at this time becomes lower when the slide 20 is moved upward, becomes upper when the slide 20 is moved downward, and is restricted by the weight guide 84 to reciprocating movement in the vertical direction. Thus, the unbalance force caused by the vertical movement of the slide 20 is canceled by the balance weight 82.

The balance weight 82 is reciprocated vertically by the bell crank 70 via the connecting body 86. For this reason, even though the balance weight 82 is connected to the bell crank 70 that moves the slide 20 up and down, the displacement of the balance weight 82 in the horizontal direction is reliably prevented, resulting from the reciprocating motion of the balance weight 82. Vibration of the press in the horizontal direction is prevented.

The reciprocating movement of the slider 34 is controlled by the guide 42
Is regulated in the vertical direction. Therefore, the bending and stretching movements of the two link mechanisms 36 are correctly synchronized, and thereby the slide 2
Horizontal vibration of the zero and balance weights 82 is reliably prevented.

When the slider 38 is moved upward by the position adjusting mechanism 40 regardless of the rotation of the crankshaft 16,
Since the bending angle of each link mechanism 36 is reduced and the swing angle of both bell cranks 70 is increased, the slide 20 is moved downward. On the other hand, slider 3
When the position 8 is moved downward by the position adjustment mechanism 40, the bending angle of each link mechanism 36 increases, and the swing angle of both bell cranks 70 decreases, so that the slide 20 moves upward.

When the slider 38 is moved upward or downward, since the position of the upper slider 34 in the vertical direction does not change, the bending angle of the link mechanism 36 (size of the bending angle range) changes, but the bending range (the bending angle range) is changed. The bending position does not move vertically. Therefore, by rotating the sprocket 66, the position of the bottom dead center and the stroke length of the slide 20 can be adjusted.

Since the press 10 uses the bell crank 70 and the position adjusting mechanism 40, there is a large difference in the sliding stroke near the bottom dead center and the top dead center as compared with the press using the toggle mechanism. Therefore, the stroke length of the slide 20 can be changed by the position adjusting mechanism 40 even though the speed can be increased.

When the position adjusting mechanism 40 is used, since the amount of movement of the slider 38 is small with respect to the amount of rotation of the worm screw 60, both the bottom dead center position and the stroke length are finely and accurately adjusted. can do. However, another position adjusting mechanism using a lever mechanism or the like may be used.

As described above, the two link mechanisms 36 and 2
If two bell cranks 70 are used, the reciprocating movement of the slide 20 and the balance weight 82 is stabilized. In particular, the two link mechanisms 36 are arranged symmetrically about the axis 52, and the bell cranks 70 are arranged symmetrically about the axis 52 on both sides thereof,
Equilibrium weight 8 above crankshaft 16 and link mechanism 36
2 are arranged symmetrically with respect to the axis 52, and the lower ends of the horizontal ends of the balance weight 82 are connected to the bell crank 70.
The reciprocating movement of the slide 20 and the balance weight 82 is stabilized.

In order to further stabilize the reciprocating movement of the slide 20 and the balance weight 82, in particular, one of the link mechanisms 3
6, one set of one connection link 74, one bell crank 70 and one connection body 86, the other link mechanism 36, the other connection link 4, and the other bell crank 7
0 and the other set consisting of the other connecting body 86
Preferably, the slide 20 and the counterweight 82 are symmetrically arranged with respect to the axis 52.

In the above embodiment, the balance device 80 is provided, but such a balance device 80 does not necessarily have to be provided. Further, instead of moving the slider 38 in the vertical direction, the slider 38 may be moved in a direction other than the vertical direction, for example, in the horizontal direction.

The present invention is not limited to the above embodiment. The present invention can be variously modified without departing from the gist thereof. For example, only one set of one link mechanism 36 and one bell crank 70 may be used.

[Brief description of the drawings]

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

FIG. 2 is an enlarged sectional view of a portion near a power transmission device and a balancing device of the press machine of FIG.

FIG. 3 is an enlarged sectional view taken along line 3-3 in FIG.

FIG. 4 is an enlarged sectional view taken along line 4-4 in FIG.

FIG. 5 is an enlarged sectional view taken along line 5-5 in FIG.

FIG. 6 is an enlarged sectional view taken along line 6-6 in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Press machine 12, 14 Frame 16 Crankshaft 18 Flywheel 20 Slide 22 Plunger 30 Power transmission device 32 Connection 34 Upper slider 36 Link mechanism 36a, 36b Link 38 Lower slider 40 Position adjustment mechanism 42, 44 Guide part 54 Bracket 56 Male screw 58 Worm wheel (rotating body) 60 Worm screw 66 Sprocket 70 Bell crank 72 Connection member 74 Connection link 76 Bracket 80 Equilibrium device 82 Balance weight 84 Weight guide 86 Connection body

Claims (8)

[Claims] 1. A crankshaft rotatably supported on a frame, and a power transmission device for transmitting rotation of the crankshaft to a slide, wherein the power transmission device is parallel to a rotation axis of the crankshaft. A bell crank supported on the frame so as to be swingable about an axis, and a connecting member that connects the bell crank and the slide so as to cause the slide to move up and down with the swing movement of the bell crank. A slider arranged on the frame movably in the up-down direction, a coupling mechanism coupled to the crankshaft, the bell crank and the slider to swing the bell crank with the rotation of the crankshaft, A position adjusting mechanism for adjusting the position of the slider in the up-down direction,
Press machine. 2. An equilibrium device having an equilibrium weight disposed on the frame so as to be able to move up and down, the balance device being connected to the bell crank to move up and down by 180 degrees in phase with the up and down movement of the slide. The press according to claim 1, comprising a balancing device. 3. The balance weight is disposed above the crankshaft, the bell crank, and the coupling mechanism so as to be vertically reciprocable on the frame, and the balance device further includes a lower end portion. The press according to claim 2, further comprising a connection body connected to the bell crank on a side of the counterweight and connected to the counterweight on a side of an upper end. 4. The bell crank has a T-shape with three arms having angles to each other, wherein one arm is connected to the connection mechanism, and the other arm is 4. The press according to claim 2, wherein the press is connected to the connection member, and the remaining arm is connected to the balancing device. 5. 5. The link mechanism according to claim 1, wherein the link mechanism includes a pair of links connected to each other so as to bend and extend with the rotation of the crankshaft, wherein one link is connected to the crankshaft and the other link is connected to the crankshaft. The press according to any one of claims 1 to 4, wherein a link includes a link mechanism connected to the slide, and a connection link that swings the bell crank in accordance with the bending and extending movement of the link mechanism. 6. The power transmission device further includes: a second bell crank supported on the frame so as to swing around an axis parallel to a rotation axis of the crank shaft; and the second bell crank. A second connecting member for connecting the second bell crank and the slide so as to make the slide move up and down with the swinging motion of the slide, and moving the second bell crank with the rotation of the crank shaft. A second coupling mechanism coupled to the crankshaft, the second bell crank, and the slide for swinging, wherein the coupling mechanism is coupled to bend and extend with the rotation of the crankshaft. First and second link mechanisms each having a pair of links, wherein one link is connected to the crankshaft and the other link is connected to the slide. First and second link mechanism,
First and second link mechanisms individually corresponding to the first and second link mechanisms and individually corresponding to the bell crank.
And a first link and a second link, each of which swings a corresponding bell crank in accordance with a bending / extending movement of a corresponding link mechanism.
A press according to any one of the preceding claims. 7. A position adjustment mechanism comprising: a bracket pivotally connected to the slider; and a disk disposed on the frame so as to be rotatable around an axis extending in one direction and immovable in the one direction. And a rotating mechanism for rotating the rotating body, wherein one of the bracket and the rotating body has a female screw hole, and the other has a male screw part screwed into the female screw hole. The press according to any one of 1 to 6. 8. The apparatus according to claim 1, further comprising a second slider disposed on said frame so as to be vertically movable, said second slider being connected to said crankshaft and said connecting mechanism. A press according to any one of the preceding claims.