JP3889930B2 - Power transmission device for press machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power transmission device for a press machine provided with a slide and a balance weight spaced in the vertical direction.
[0002]
[Prior art]
One of the presses that convert the rotational movement of the crankshaft into the reciprocating movement of the slide is one that uses a toggle mechanism in a power transmission device (for example, Japanese Patent Publication No. 7-55399). In this press machine, the slide is moved using two sets of link mechanisms, and the stroke length of the slide can be changed using a position adjusting mechanism.
[0003]
[Problems to be solved]
However, since this press machine uses two sets of link mechanisms, the structure is complicated.
[0004]
An object of the present invention is to simplify the structure of a press machine including a toggle mechanism and a slide stroke length adjusting mechanism.
[0005]
[Solution, action and effect]
A press machine according to the present invention is a power transmission device for a press machine that transmits the rotational movement of a crankshaft to a slide that is vertically spaced to move the slide up and down, and is spaced apart from each other in the vertical direction. and first and second sliders disposed movable frame vertically, a connection for connecting the first slider to the eccentric portion of the crankshaft, is bendable pivot connected to each other and the first and First and second link pieces pivotally connected to the second slider, respectively, and first and second link pieces pivotally connected to pivot connection points of the first and second link pieces and pivotally connected to a plunger extending from the slide. 3 link pieces, and a position adjusting mechanism for adjusting the height position of the second slider in the vertical direction.
[0006]
The rotational movement of the crankshaft is transmitted to the first and second link pieces by the connection, and the first and second link pieces are bent and stretched. The bending and stretching movements of the first and second link pieces are transmitted to the third link piece pivotally connected to the pivot connection point of the first and second link pieces, and are moved from the third link piece to the slide by the plunger. Communicated. Thus, the slide is reciprocated in the vertical direction with the bending and stretching movements of the first and second link pieces.
[0007]
When the height position of the second slider in the vertical direction is changed by the position adjustment mechanism, the bending angle of the first and second link pieces is changed, and the stroke length of the slide is changed.
[0008]
When the pivot connection point of the first and second link pieces is pivotally connected to the plunger extending from the slide by the third link piece, the link piece pivotally connected to the frame is not required, so A pivot and a bracket are also unnecessary, and the structure is simplified.
[0009]
The plunger is arranged so as not to move in the horizontal direction on the frame, so that the movement of the pivot connection point between the plunger and the third link piece in the horizontal direction and the movement of the slide in the horizontal direction are possible. This prevents the slide from moving stably.
[0010]
In a preferred embodiment, the position adjusting mechanism is configured to rotate around the axis extending in one direction and to rotate in the direction of rotation, and a disk-shaped rotating body arranged on the frame so as not to move in the one direction. One of the second slider and the rotating body has a female screw hole, and the other of the slider and the rotating body has a male screw portion screwed into the female screw hole.
[0011]
The press machine further includes other first and second link pieces pivotably connected to each other and pivotally connected to the first and second sliders, respectively, and the other first and second links. is pivotally connected to the pivot connection point of the piece, and seen contains and another third link piece is pivotally connected to the other of the plunger extending from said slide, said first, said another second and third link piece The first, second, and third link pieces may be arranged symmetrically with respect to an axis extending in the vertical direction via the rotation center of the crankshaft . By doing so, since the slide is connected to the link mechanism at two places, the movement of the slide is stabilized.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 to 5, the press machine 10 includes a lower frame 12 on which a lower mold is placed, and an upper frame 14 supported by the lower frame 12. 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 the rotation of the flywheel 18 shown in FIG. A so-called slide 20 that supports the upper mold is assembled to the lower ends of a pair of plungers 22 that pass through the lower end of the upper frame 14 so as to be movable in the vertical direction.
[0013]
Both plungers 22 extend upward in parallel from both ends of the slide 20 and are reciprocated in the vertical direction by a power transmission device 30 that converts the rotational motion of the crankshaft 16 into reciprocating motion in the vertical direction. Thereby, the slide 20 is reciprocated up and down.
[0014]
The power transmission device 30 includes a connection 32 coupled to the crankshaft 16 and a pair of first couplings disposed on the upper frame 14 so as to be reciprocable in the vertical direction and pivotally connected to the connection 32, that is, pivotally coupled to the connection 32 . The slider 34, a pair of link mechanisms 36 (first link piece 36a and second link piece 36b) which are bent and extended following the reciprocation of the first slider 34 and in synchronization with each other, and the link mechanism 36 A pair of third link pieces 38 which are individually moved and moved up and down following the bending and stretching movements of the corresponding link mechanisms 36, and are arranged on the upper frame 14 so as to be vertically displaceable and pivoted on both link mechanisms 36. A pair of second sliders 40 that are connected to each other and a position adjusting mechanism 42 that adjusts the position of the second slider 40 in the vertical direction.
[0015]
The connection 32 is connected to the eccentric portion of the crankshaft 16 and is reciprocated in the vertical direction as the crankshaft 16 rotates. The first and second sliders 34 and 40 are arranged on a guide portion 44 formed on the upper frame 14 so as to be movable in the vertical direction. The first sliders 34 are reciprocated in the vertical direction following the reciprocation of the connection 32. The second sliders 40 are not reciprocated in the vertical direction by the bending and stretching movements of the link mechanisms 36.
[0016]
Each link mechanism 36 includes first and second link pieces 36a and 36b. Both the link piece 36a, 36b of each link mechanism 36, the upper end portion of the lower end portion of the first link piece 36a and the second link piece 36b, and is flexibly connected to one another by a pivot 46. Each pivot 46 pivotally connects both link pieces 36 a and 36 b of the link mechanism 36 to the upper end portion of the corresponding third link piece 38.
[0017]
The first link pieces 36a of both the link mechanisms 36 are connected to the connection 32 and the first slider 34 at the upper end portion by a common pivot 48 so as to be pivotable. The second link pieces 36b of both the link mechanisms 36 are connected to the second slider 40 at the lower end by a common pivot 50 so as to be pivotable.
[0018]
In the illustrated example, the pivots 48 and 50 are provided so that their pivot points coincide with an axis 52 (see FIG. 2) extending in the vertical direction via the rotation center of the crankshaft 16. However, the pivots 48 and 50 need not be so arranged.
[0019]
In the illustrated example, also, the first link piece 36a of the link mechanism 36 is directly coupled to the connection 32 and the first slider 34, a connection 32 and the first slider 34 and the pivot coupling, link The first link piece 36 a of the mechanism 36 may be pivotally connected to only one of the connection 32 and the first slider 34.
[0020]
Each third link piece 38 is connected to the pivot connecting point of both link pieces 36a and 36b of the corresponding link mechanism 36 at the upper end portion by the pivot 46, and can be pivotally moved to the plunger 22 by the pivot 54 at the lower end portion. It is connected.
[0021]
Position adjusting mechanism 42 includes a second of the two link pieces 36b and bifurcated bracket 70 which is pivotally movably connected to the second of the two sliders 40 by the pivot 50, a male screw 72 extending downward from the bracket 70, the male screw 72 includes a worm wheel 74 screwed, a worm screw 76 that meshes engagement with the worm wheel 74. Instead of using the bracket 70, the male screw 72 may be connected to the second link pieces 36 b and the second slider 40 by the pivot 50 so as to be pivotable.
[0022]
The male screw 72 is connected to the bracket 70 so as not to rotate around the axis 52. The worm wheel 74 is supported by the support portions 78 and 80 of the upper frame 14 so as to be rotatable around the axis 52 and not movable in the vertical direction. The shaft portion of the worm screw 76 passes through the upper frame 14 in a rotatable manner, and includes a sprocket 82 at the end (see FIG. 4). The sprocket 82 is rotated by a rotation mechanism (not shown) such as an electric motor.
[0023]
When the sprocket 82 is rotated, the worm screw 76 is rotated, the worm wheel 74 is rotated to engage engagement with the worm screw 76, worm wheel 74 and screwed to the male screw 72 is moved upward or downward, and finally the The second slider 40 is moved upward or downward.
[0024]
In the press 10, the first slider 34 is reciprocated in the same direction as the connection 32 is reciprocated in the vertical direction as the crankshaft 16 rotates. However, the second slider 40 is not moved unless the worm wheel 74 is rotated. Therefore, the pivot 48 acts as a movable fulcrum for the link mechanism 36, and the pivot 50 acts as a fixed fulcrum for the link mechanism 36.
[0025]
The pivots 46, 48, 50 and 54 extend in the horizontal direction in parallel with the rotation axis of the crankshaft 16. Therefore, the pivotal movement of the members connected to each other by the pivots or the members supported by the pivots is a movement around the axis extending in the horizontal direction.
[0026]
When the rotation of the flywheel 18 is transmitted to the crankshaft 16, the connection 32 and the first slider 34 are reciprocated in the vertical direction along with the rotation of the crankshaft 16, so that both link mechanisms 36 are synchronized. Bend and stretch. As a result, the third link pieces 38 are moved up and down synchronously, and as a result, the slide 20 is reciprocated in the up and down direction.
[0027]
The reciprocating movement of the slide 20 is restricted in the vertical direction by restricting the reciprocating movement of the plunger 22 in the vertical direction by the frame 14. For this reason, although the third link piece 38 is not supported by the frame 14, the displacement of the slide 20 in the horizontal direction is surely prevented and the vertical movement of the slide 20 is stabilized.
[0028]
The reciprocating motion of the first slider 34 is regulated in the vertical direction by the guide portion 44. For this reason, the bending / extending motions of both link mechanisms 36 are correctly synchronized, thereby reliably preventing the vibration of the slide 20 in the horizontal direction.
[0029]
Regardless of the rotation of the crankshaft 16, when the second slider 40 is moved upward by the position adjusting mechanism 42, the bending angle of each link mechanism 36 decreases, and thereby the bending angle of each third link piece 38. Therefore, the slide 20 is moved downward. On the other hand, when the second slider 40 is moved downward, the bending angle of each link mechanism 36 is increased, whereby the bending angle of each third link piece 38 is decreased, so that the slide 20 is moved upward. Moved.
[0030]
When the second slider 40 is moved upward or downward, since the position of the first slider 34 in the vertical direction does not change, the bending angle of the link mechanism 36 changes, but the bending / extension range does not translate in the vertical direction. . For this reason, the bottom dead center position and the stroke length of the slide 20 can be adjusted by rotating the sprocket 82.
[0031]
The bottom dead center position of the slide 20 is adjusted by detecting this with an arbitrary detector, comparing the detected value with a predetermined reference value, and rotating the sprocket 82 so that the detected value becomes the reference value. May be. The stroke length of the slide 20 can be set by rotating the sprocket 82 by a predetermined amount in advance.
[0032]
If the position adjusting mechanism 42 is used, the amount of movement of the second slider 40 relative to the amount of rotation of the worm screw 76 is minute, so both the bottom dead center position and the stroke length are finely and accurately adjusted. can do. However, another position adjustment mechanism using a lever mechanism or the like may be used.
[0033]
If the two link mechanisms 36 and the two third link pieces 38 are used as described above, the reciprocating movement of the slide 20 is stabilized. In particular, if both the link mechanisms 36 are arranged symmetrically with respect to the axis 52 and the third link pieces 38 are arranged symmetrically with respect to the axis 52 on both sides thereof, the reciprocating movement of the slide 20 is stabilized.
[0034]
In order to further stabilize the reciprocating movement of the slide 20, in particular, one set of the first, second and third link pieces 36a, 36b, 38 and the other set of the first, second and third links The link pieces 36a, 36b, 38 are preferably arranged symmetrically with respect to the axis 52. However, for example, only one set of link mechanism 36 and link piece 38 may be used.
[0035]
The present invention is not limited to the above embodiments. The present invention can be variously modified without departing from the gist thereof.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional front view showing an embodiment of a press machine according to the present invention.
FIG. 2 is an enlarged cross-sectional view of a portion of a power transmission device and a balance device of the press machine of FIG.
FIG. 3 is an enlarged cross-sectional view taken along line 3-3 in FIG.
4 is an enlarged cross-sectional view taken along line 4-4 in FIG.
FIG. 5 is an enlarged cross-sectional view taken along line 5-5 in FIG.
[Explanation of symbols]
10 presses 12, 14 the frame 16 crankshaft 18 flywheel 20 slide 22 the plunger 30 power transmission device 32 connections 34, 40 first and second slider 36 link mechanism 36a first link piece 36b second link piece 38 second Link piece 3 42 Position adjustment mechanism 44, 62 guide portion
62 connector 70 bracket 72 male screw 74 worm wheel 76 worm screw 78, 80 support portion 82 sprocket

Claims (4)

A power transmission device for a press machine that transmits the rotational movement of the crankshaft to a slide spaced vertically to move the slide up and down,
First and second sliders arranged on the frame so as to be spaced apart from each other in the vertical direction and movable in the vertical direction;
A connection connecting the first slider to the eccentric part of the crankshaft;
First and second link pieces pivotably connected to each other and pivotally connected to the first and second sliders, respectively;
A third link piece pivotally connected to a pivot connection point of the first and second link pieces and pivotally connected to a plunger extending from the slide;
And a position adjusting mechanism for adjusting a height position of the second slider in the vertical direction.   The power transmission device according to claim 1, wherein the plunger is disposed on the frame so as not to move horizontally.   The position adjusting mechanism includes a disk-shaped rotating body arranged on the frame so as to be rotatable about an axis extending in one direction and not movable in the one direction, and a rotating mechanism for rotating the rotating body. 3. Either one of the second slider and the rotating body has a female screw hole, and the other of the slider and the rotating body has a male screw portion screwed into the female screw hole. Power transmission device.   Further, the other first and second link pieces pivotably connected to each other and pivotally connected to the first and second sliders, respectively, and the other first and second link pieces pivotally connected. Another third link piece pivotally connected to a point and pivotally connected to another plunger extending from the slide, the first, second and third link pieces and the other first, first 4. The power transmission device according to claim 1, wherein the second and third link pieces are symmetrically arranged with respect to an axis extending in a vertical direction via a rotation center of the crankshaft.

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