JP4274629B2 - Press machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a press machine that reciprocates a slide by bending and stretching a pair of levers by rotation of a crankshaft.
[0002]
[Prior art]
As one of the press machines, there is a press machine using a link mechanism such as a knuckle mechanism or a toggle mechanism (for example, JP-A-10-109194). This press machine has a crankshaft rotated by a driving source, a link mechanism in which an upper lever having a fixed fulcrum and a lower lever having a movable fulcrum are pivotally connected to each other, and both levers are rotated by the crankshaft. And a position adjusting mechanism for connecting the fixed fulcrum to the frame so that the position of the fulcrum can be adjusted. The upper slide is connected to the movable fulcrum.
[0003]
The coupling mechanism couples the crankshaft and the coupling mechanism by a pair of links coupled so as to be able to bend and extend, and restricts the moving direction of the pivot coupling point of both links in the horizontal direction by a plurality of auxiliary links. The position adjusting mechanism moves the fixed fulcrum in the moving direction of the pivot connection point of both links, thereby changing the bending angle of both levers and changing the stroke length of the slide.
[0004]
[Problems to be solved]
However, in the above conventional press machine, the moving direction of the fixed fulcrum is horizontal, so when the stroke length is changed, the lever having the fixed fulcrum is rotated angularly around the pivot connection point of both levers. The pivot connecting point of both levers is displaced in the vertical direction, so that the bottom dead center position of the upper slide changes. When the bottom dead center position changes in this way, the positional relationship between the upper and lower molds changes. Therefore, the positional relationship between the upper and lower molds must be adjusted each time the stroke length is adjusted.
[0005]
Therefore, in this type of press, it is important that the bottom dead center position does not change even if the slide stroke length is changed.
[0006]
[Solution, action and effect]
The press according to the present invention includes a frame, a crankshaft disposed on the frame so as to be rotatable around an axis extending in a first direction, and a second direction extending in a direction intersecting the first direction. A slide disposed on the frame so as to be capable of reciprocating; and one or more motion converters for reciprocating the slide as the crankshaft rotates.
[0007]
The motion conversion device interconnects a first lever having a fixed fulcrum and a second lever having a movable fulcrum connected to the slide so as to be capable of bending and extending around an axis extending in the first direction. A link mechanism, a connecting mechanism for causing the levers to bend and extend as the crankshaft rotates, and a position adjusting mechanism for connecting the fixed side fulcrum to the frame, around the connecting axis of the levers. And a position adjusting mechanism that adjusts the position of the fixed-side fulcrum on an arc that is convex on the side opposite to the slide side.
[0008]
When both levers bend and extend, the fixed side fulcrum does not move, but the movable side fulcrum reciprocates in the second direction, whereby the slide is reciprocated in the second direction. When the position of the fixed fulcrum around the connecting axis of both levers is changed, the angle of the bending and stretching movements of both levers is changed, thereby changing the stroke length of the reciprocating movement of the slide.
[0009]
When changing the stroke length, the first lever is rotated angularly around the connecting axis of both levers, but the position of the fixed fulcrum is changed around the connecting axis of both levers. The position of the connecting axis does not change. Thereby, even if the stroke length is changed, the bottom dead center position is not changed.
[0010]
The position adjusting mechanism is a rotating body pivotally connected to the first lever at the fixed fulcrum, and the pivot connecting point to the first lever is rotatable around the connecting axis of the two levers. And a rotating mechanism that rotates the rotating body around the connecting axis of the two levers. In this way, the position of the rotating body around the connecting axis of the two levers can be finely adjusted. Therefore, the slide stroke length can be finely adjusted.
[0011]
The rotating body may include a gear having external teeth extending in an arc around the connecting axis of the two levers, and the rotating mechanism may include a worm screw portion that meshes with the gear. In this way, the position of the gear around the connecting axis of both levers can be adjusted by the worm screw, so that the stroke length of the slide can be adjusted more finely.
[0012]
The connection mechanism includes a first link pivotally connected to the eccentric shaft portion of the crankshaft, a second link pivotally connected to the first link and the levers, and the second link. And a restricting tool for restricting the position of the pivot connecting portion of both the links in the direction of the. In this way, the positions of the pivot connecting portions of the first and second links in the second direction are restricted, so that the bending motion of the first and second levers and the first and second links is smooth. And the reciprocating motion of the slide becomes smooth.
[0013]
The restricting tool is a first auxiliary link extending in a second direction, the first auxiliary link pivotally connected to the pivot coupling portion of the first and second links at the lower end, and the first auxiliary link A pair of second links pivotally connected to one end of one auxiliary link spaced apart in a third direction intersecting the first and second directions and pivotally connected to the frame; And an auxiliary link.
[0014]
In addition, the balance includes a pair of balance weights arranged on the outside of the motion conversion device, and each balance weight is pivotally connected to the frame and the movable side fulcrum by third and fourth auxiliary links at the upper end and the lower end, respectively. Each fourth auxiliary link is pivotally connected to the frame by a fifth auxiliary link at an intermediate portion thereof. In this way, the vibration of the press machine is remarkably reduced.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 and 2, a press machine 10 includes a frame 12 and a crank rotatably supported on an upper portion of the frame 12 about an axis extending in a front-rear direction (a direction perpendicular to the paper surface in FIG. 1). It includes a shaft 14, a bolster 16 mounted on the lower part of the frame 12, and a slide 18 for assembling the upper mold.
[0016]
The crankshaft 14 is rotated at a constant speed by a drive source (not shown) such as an electric motor. Although not shown, the crankshaft 14 is supported by the frame 16 at a plurality of main shaft portions, and has a pair of eccentric main shaft portions. Both eccentric shaft portions have the same amount of eccentricity, but the eccentric direction is shifted by 180 degrees around the crankshaft 14.
[0017]
The slide 18 is attached to the lower ends of a pair of rods 20 penetrating through the intermediate portion of the frame 12 so as to be movable in the vertical direction, and is regulated by the frame 12 to reciprocate in the vertical direction.
[0018]
The press machine 10 also includes a pair of motion converters 22 that reciprocate the slide 18 in the vertical direction as the crankshaft 14 rotates, and a pair of balance weights 24. The motion conversion device 22 is symmetrically disposed on the top of the frame 12 with the crankshaft 14 in between, and the balance weight 24 is symmetrically disposed on the top of the frame 12 with the motion conversion device 22 in between.
[0019]
Each motion converter 22 connects the upper and lower levers 26 and 28 connected to bendable / extendable to the crankshaft 14 by a pair of links 30 and 32 connected to bendable / extendable, and the upper lever 26 is moved by a position adjusting mechanism 34. It is connected to the frame 12.
[0020]
The pivot 36 forming the connection axis of the levers 26 and 28 and the pivot 38 forming the connection axis of the links 30 and 32 extend parallel to the rotation axis of the crankshaft 14, so that the levers 26 and 28 and the links 30 and 32 are They can bend and stretch in a plane perpendicular to their connecting axis. The upper and lower levers 26 and 28 are connected to each other by pivots at the lower end and the upper end, respectively.
[0021]
The upper lever 26 is connected to the position adjusting mechanism 34 at the upper end portion by a pivot 40 having an axis acting as a fixed side fulcrum. The lower lever 28 is connected to the upper end of the rod 22 at the lower end by a pivot 42 having an axis that acts as a movable fulcrum.
[0022]
The link 30 is pivotally connected to one eccentric shaft portion of the crankshaft 14, and the link 32 is connected to a connection portion of both levers 26 and 28 by a pivot shaft 36. The position of the pivot 38 in the vertical direction (that is, the position of the connecting axis of the links 30 and 32) is regulated in the horizontal direction by a regulating tool. Such a restricting tool includes a T-shaped auxiliary link 44 extending in the vertical direction, and a pair of auxiliary links 46 extending in an eight-character shape obliquely downward from a position spaced in the left-right direction at the upper end of the auxiliary link 44. Prepare.
[0023]
The auxiliary ring 44 is pivotally connected to the pivot coupling portions of the links 30 and 32 by the pivot 38 at the lower end. Both auxiliary links 46 are connected to the upper end of the auxiliary link 44 at the upper end by a pivot extending in the front-rear direction at a position spaced in the left-right direction, and to the bracket part 48 provided on the frame 12 in the front-rear direction. It is connected by an extending pivot.
[0024]
Each position adjusting mechanism 34 includes a rotating body 50 connected to the upper end of the upper lever 26 by a pivot 40 forming a fixed fulcrum, and a pivot 36 connecting the rotating body 50 to both levers 26 and 28. And a rotating mechanism 52 for rotating. The rotation mechanisms 52 of both the position adjustment mechanisms 34 are rotated by the same amount manually or synchronously by an electric motor.
[0025]
In the example shown in FIGS. 3 and 4, the rotating body 50 includes a gear having outer teeth 54 on the outer peripheral surface extending in an arc around the pivot 36, and the rotating mechanism 52 is a worm screw portion that meshes with the outer teeth of the rotating body 50. And a rod-shaped member that penetrates the bracket portion 48.
[0026]
The rotating body 50 has a plurality of arcuate guides or auxiliary members provided on the frame 12 such that a pivot connecting point (fixed side fulcrum) to the upper lever 26 is angularly rotated along an arc around the pivot 36. The tool 58 is assembled to the frame 12.
[0027]
As shown in FIG. 4, the rotating body 50 has an outer peripheral surface extending in a band shape, an external tooth 54 is formed at the center in the width direction of the outer peripheral surface, and both edges in the width direction of the outer peripheral surface are framed. The 12 arcuate inner surfaces 60 and the auxiliary tools 58 are brought into contact with each other.
[0028]
Each balance weight 24 extends in the vertical direction, and is pivotally connected to the bracket portion 48 and the movable side fulcrum by auxiliary links 62 and 64 at the upper end portion and the lower end portion, respectively. The auxiliary rings 62 and 64 extend in parallel in the left-right direction. The auxiliary link 64 is pivotally connected to the frame 12 in the middle in the longitudinal direction by an auxiliary link 66 extending in the vertical direction.
[0029]
In the press 10, when the crankshaft 14 is rotated, the link 30 is moved in the left-right direction as the eccentric shaft portion of the crankshaft 14 rotates. At this time, since the movement of the pivot connecting portion of both the links 30 and 32 is restricted in the horizontal direction by the auxiliary levers 44 and 46, the link 32 is moved in the left-right direction. As a result, the pivot connecting portions of the levers 26 and 28 are forcibly moved in the left-right direction, and the levers 26 and 28 bend and extend.
[0030]
When the levers 26 and 28 are bent and extended, the fixed fulcrum (the pivot 40) does not move, but the movable fulcrum (the pivot 42) reciprocates in the vertical direction. As a result, the slide 18 is reciprocated in the vertical direction, and each balance weight 24 is shifted 180 degrees from the slide 18 and reciprocated in the vertical direction.
[0031]
When the position of the fixed fulcrum around the connecting axis (the pivot axis 36) of both levers 26, 28 is changed, the bending angle range of both levers 26, 28 is changed as the crankshaft 14 rotates. Thereby, the stroke length of the reciprocating motion of the slide 18 is changed.
[0032]
When changing the stroke length, the rotating body 50 is rotated angularly about the pivot 36 by the rotating mechanism 52, whereby the upper lever 26 is rotated angularly about the connecting axis of both levers 26, 28. . However, at this time, the position of the fixed fulcrum is changed around the connecting axis of the levers 26 and 28, so the position of the connecting axis of the levers 26 and 28 in the vertical direction does not change. Thereby, even if the stroke length is changed, the bottom dead center position is not changed.
[0033]
FIG. 5 schematically shows the positional relationship among the levers 26 and 28, the links 30 and 32, the pivots 36, 38, 40 and 42, and the slide 18 when the stroke length of the slide 18 is changed. 5, (A), (C), and (E) show the state in which the slide 18 is displaced to the bottom dead center where the angle formed by both levers 26 and 28 is the largest, and (B), (D ), (F) show a state in which the slide 18 is displaced to the top dead center where the angle formed by the levers 26, 28 is the smallest.
[0034]
As apparent from FIG. 5, since the position of the pivot 38 in the vertical direction is always regulated by the restricting tool, even if the position of the pivot 40 is changed around the pivot 36, the rotation axis of the crankshaft 14 The distance L1 to the lower end surface of the slide 18 does not change, and therefore the bottom dead center position does not change.
[0035]
On the other hand, when the position of the pivot 40 is changed, the angles of the levers 26 and 28 at the top dead center position and the bottom dead center position are changed. Therefore, the rotation of the crankshaft 14 depends on the position of the pivot 40 around the pivot 36. The distances L21, L22, L23 from the axis to the lower end surface of the slide 18 change, and therefore the position and stroke length of the slide 18 at the top dead center are different.
[0036]
As a result, the pivot connecting point of the levers 26 and 28 (the center of the pivot 36) is moved, so that the bending positions and bending angles of the links 30 and 32 and the levers 26 and 28 are changed as the crankshaft 16 rotates. The stroke lengths L01, L02, and L03 of the vertical movement of the slide 18 change. Therefore, by rotating the rotation mechanism 34, the stroke length of the vertical movement of the slide 18 can be finely adjusted.
[0037]
In the above embodiment, instead of using the rotating body having the external gear 54, other flat-plate rotating bodies such as an internal gear, a toothed wheel, a sprocket, and a timing pulley may be used. Further, instead of the worm screw, a rotation mechanism including other members such as a small gear, a ratchet, a chain, a timing pulley, and a timing belt may be used according to the rotating body.
[0038]
The present invention is not limited to the above embodiments. For example, the present invention can be applied to a pressing machine in which the moving direction of the upper slide is in another direction such as a horizontal direction or an oblique direction. Therefore, the present invention can be variously modified without departing from the gist thereof.
[Brief description of the drawings]
FIG. 1 is a partially sectional front view showing an embodiment of a press machine according to the present invention. FIG. 2 is an enlarged view of an upper portion of the press machine shown in FIG. 1. FIG. FIG. 4 is a cross-sectional view taken along line AA in FIG.
FIG. 5 is a diagram for explaining the slide height position when the slide stroke length is changed.
DESCRIPTION OF SYMBOLS 10 Press machine 12 Frame 14 Crankshaft 16 Bolster 18 Slide 20 Rod 22 Slide motion converter 24 Balance weight 26, 28 Lever 30, 32 Link 34 Position adjustment mechanism 36, 38, 40, 42 Pivot 44, 46, 62 for connection 64 Auxiliary link 50 Rotating body 52 Rotating mechanism 54 Gear 56 Worm screw

Claims (6)

A frame, a crankshaft disposed on the frame for rotation about an axis extending in a first direction, and a reciprocating motion in a second direction extending in a direction intersecting the first direction. And one or more motion converters that reciprocate the slide as the crankshaft rotates,
The motion conversion device interconnects a first lever having a fixed fulcrum and a second lever having a movable fulcrum connected to the slide so as to be capable of bending and extending around an axis extending in the first direction. A link mechanism, a connecting mechanism for causing the levers to bend and extend as the crankshaft rotates, and a position adjusting mechanism for connecting the fixed side fulcrum to the frame, around the connecting axis of the levers. A press machine comprising: a position adjusting mechanism that adjusts a position of the fixed side fulcrum on an arc that is convex on the side opposite to the slide side.   The position adjusting mechanism is a rotating body pivotally connected to the first lever at the fixed fulcrum, and the pivot connecting point to the first lever is rotatable around the connecting axis of the two levers. The pressing machine according to claim 1, further comprising: a rotating body that rotates the rotating body around a connecting axis of the levers.   3. The press according to claim 1, wherein the rotating body includes a gear having external teeth extending in an arc around the connecting axis of the two levers, and the rotating mechanism includes a worm screw portion that meshes with the gear.   The connection mechanism includes a first link pivotally connected to the eccentric shaft portion of the crankshaft, a second link pivotally connected to the first link and the levers, and the second link. The press according to claim 1, 2 or 3, further comprising: a restricting tool for restricting a position of the pivot connecting portion of the both links in the direction of.   The restricting tool is a first auxiliary link extending in a second direction, the first auxiliary link pivotally connected to the pivot coupling portion of the first and second links at the lower end, and the first auxiliary link A pair of second links pivotally connected to one end of one auxiliary link spaced apart in a third direction intersecting the first and second directions and pivotally connected to the frame; The press according to claim 4, comprising an auxiliary link.   In addition, the balance includes a pair of balance weights arranged on the outside of the motion conversion device, and each balance weight is pivotally connected to the frame and the movable side fulcrum by third and fourth auxiliary links at the upper end and the lower end, respectively. The press according to any one of claims 1 to 5, wherein the presses are connected and each fourth auxiliary link is pivotally connected to the frame by a fifth auxiliary link at an intermediate portion thereof.

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