JPH04344891A - Device for transmitting motive power of press - Google Patents

Abstract

PURPOSE:To transform a constant rotary motion to an inconstant rotary motion without using gears. CONSTITUTION:The device is characterized by that a first transmission means 40, which is rotated by receiving the rotation of a flywheel 14, and a second transmission means 42, which is rotated by the rotation of the first transmission means, are essentially on a common rotary axis line P1; that the pivot P54, which is rotatably moved along an imaginary circle 66 having as its center an eccentric point P2 from the rotary axis line of the first transmission means, is formed on a third transmission means 44, 46 which is pivotally connected to the second transmission means; and that the third transmission means is pivotally connected by means of a fourth transmission means 48 to a fifth transmission means 50 which is connected to a crank shaft 16 to rotate the crank shaft.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission device for a press machine that transmits the rotational motion of a flywheel to a crankshaft.

0002

2. Description of the Related Art Generally, a power transmission device for a press machine, which converts uniform rotational motion of a flywheel into nonuniform rotational motion and transmits the same to a crankshaft, receives the rotation of the flywheel and transmits the rotational motion of the flywheel. It includes a pinion gear rotated around an axis, a main gear meshed with the pinion gear, and a pair of links that transmit the rotation of the main gear to the crankshaft (for example, Japanese Patent Laid-Open No. 124498/1983) reference). One link is pivotally connected at one end to an eccentric portion of the main gear, and the other link is pivotally connected to the other end of the one link and fixed to the crankshaft. There is.

However, in the conventional power transmission device described above, since the rotational axes of the two gears are separated from each other, an unbalanced force acts between the two gears, resulting in vibration. In addition, the power transmission device becomes large and complicated by an amount corresponding to the distance between the rotational axes of both gears.

0004

SUMMARY OF THE INVENTION An object of the present invention is to convert uniform rotational motion into inconstant rotational motion without using gears.

[0005]

[Solution, operation, and effect] The power transmission device for a press machine of the present invention provides a first
a second transmitting means rotated by the rotation of the first transmitting means and having an essentially common axis of rotation with the first transmitting means; a second transmitting means rotated by the rotation of the second transmitting means; a third transmission means pivotally connected to the second transmission means to rotate along an imaginary circle centered on a point eccentric to the rotational axis of the first transmission means; a third transmission means having a pivot point to be moved; a fourth transmission means pivotally connected to said third transmission means to be rotated by rotation of said third transmission means; a fifth transmission means pivotally connected to the fourth transmission means to be rotated by the rotation of the transmission means, and a fifth transmission means connected to the crankshaft to rotate the crankshaft.

[0006] The first and second transmission means perform uniform rotational motion in accordance with the uniform rotational motion of the flywheel. However, since the rotation center of the third transmission means is eccentric with respect to the rotation axis of the first transmission means,
It performs non-uniform rotational motion along with the uniform rotational motion of the flywheel. This non-uniform rotational motion is transmitted to the fifth transmission means via the fourth transmission means, and is transmitted to the crankshaft by the fifth transmission means. When a uniform rotational motion is converted into an inconstant rotational motion, adjacent transmission means undergo relative angular rotation due to their pivotal connection, and the third transmission means rotates about its pivot point. performs an angular rotation. This absorbs the difference between the angular velocity of the first transmission means that rotates at a constant speed and the angular velocity of the fifth transmission means that rotates at an inconstant speed. The rotational speed of the fifth transmission means relative to the rotation angle of the first transmission means, that is, the reciprocating speed of the slide is determined by the distance between the rotation axis of the first transmission means and the rotation center of the pivot point of the third transmission means. , the direction of relative displacement between the rotational axis of the first transmission means and the rotation center of the pivot point of the third transmission means, the distance between the pivot points of adjacent transmission means, etc.

According to the invention, the first and second transmission means have essentially a common axis of rotation, and the third transmission means has an eccentric point with respect to the axis of rotation of the first transmission means. Since it has a pivot point that rotates along a virtual circle as the center, it is possible to convert uniform rotational motion to inconstant rotational motion without using gears as the first and second transmission means. Moreover, no unbalanced force acts between the first and second transmission means.

Preferably, the axis of rotation of the first transmission means essentially coincides with the axis of rotation of the flywheel. This makes the device smaller and simpler than known devices using a pair of gears and a pair of links. The third transmission means includes a link that is pivotally connected to the first transmission means, and a link that is pivotally connected to the link on a virtual circle centered on the eccentric point, and and an annular member rotatable about a point essentially as a center of rotation. The fifth transmission means may be mounted on the crankshaft such that its axis of rotation essentially coincides with the axis of rotation of the crankshaft.

[0009] It is preferable that the first transmission means rotatably support the flywheel and support a clutch/brake mechanism provided in association with the flywheel in a relatively unrotatable manner. This results in
Compared to known devices using a pair of gears and a pair of links, the device becomes more compact and simpler. The rotational axis of the fifth transmission means may be an axis extending parallel to and separated from the rotational axis of the first transmission means; Therefore, it is preferable that the rotational axes of the first and fifth transmission means essentially coincide.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a press machine 10 has a power transmission device 12 of the present invention disposed between a flywheel 14 and a crankshaft 16.

As shown in FIGS. 3 to 6, the flywheel 14 is rotatably supported on the power transmission device 12 by a plurality of bearings 18 about an axis extending in the horizontal direction. On the other hand, the crankshaft 16 is rotatably supported by a frame 22 of the press 10 by a plurality of bearings 20 around an axis extending in the horizontal direction. The rotation axis of the flywheel 14 and the rotation axis of the crankshaft 16 are aligned with each other.

Motor 24 attached to frame 22
The rotation is caused by the pulley 2 attached to the rotating shaft of the motor.
6 and a belt 28 wound around the pulley and the flywheel 14, the transmission is transmitted to the flywheel 14, and further from the flywheel 14 to a known clutch/brake mechanism 3 disposed in relation to the flywheel.
0 and is transmitted to the crankshaft 16 via the power transmission device 12.

The crankshaft 16 has two eccentric parts, and a common slide 34 is supported on the eccentric parts via a connector 32. The slide 34 is reciprocated in the vertical direction with respect to a bolster 36 attached to the frame 22 as the crankshaft 16 rotates. Displacement of the slide 34 in the horizontal direction is regulated by a pair of guide rods 38 attached to the frame 22 in parallel with each other.

As shown in FIGS. 2 to 6, the power transmission device 12
The rotating shaft 40 receives the rotational motion of the flywheel 14 via the clutch/brake mechanism 30, the arm 42 is attached at one end to the end of the rotating shaft 40, and the arm 42 is connected to the other end of the arm 42 at one end. The connected first link 44 is connected to the first link 44 on a virtual circle 66 centered on a point P2 eccentric from the rotation axis P1 of the rotating shaft 40, and rotates around the eccentric point P2. a second link 48 connected at one end to the other end of the first link 44; and a lever 50 connected at one end to the other end of the second link 48. include.

The arm 42 and the first link 44, the first link 44 and the annular member 46, the first link 44 and the second link 48, and the second link 48 and the lever 50 are as follows:
They are pivotally connected by pins 52, 54, 56 and 58, respectively. Below, pins 52, 54, 5
The rotation axes of 6 and 58 are P52 and P54, respectively.
, P56 and P58.

The arm 42 has a plurality of bearings 6 so that its axis of rotation P1 coincides with the axis of rotation of the crankshaft 16.
0 rotatably supported on the crankshaft 16,
Further, the flywheel 14 is rotatably supported by a plurality of bearings 62 so as to have a common axis of rotation with the flywheel 14, and the clutch/brake mechanism 3 has a common axis of rotation with the clutch/brake mechanism 30.
0 is supported relatively unrotatably.

The annular member 46 has a ring portion rotatably supported around a point P2 by a guide ring 64 attached to the side of the frame 22, and a protrusion portion that protrudes inward from the ring portion. and is connected to the first link 44 at the protrusion so as to be pivotable about an axis P54.

The lever 50 is relatively non-rotatably attached to the crankshaft 16 so that its axis of rotation coincides with the axis of rotation of the crankshaft 16 and so as to transmit rotational motion to the crankshaft 16.

When the rotation of the flywheel 14 is transmitted to the rotating shaft 40 via the clutch/brake mechanism 30, the arm 42 is rotated together with the rotating shaft 40, thereby causing the first link 44, the annular member 46, and the second link 48 and lever 50 are rotated, and finally crankshaft 16 is rotated by lever 50.

As the rotating shaft 40 rotates, the arm 4
2 is rotated around the rotation axis P1 of the rotation shaft 40, whereas the connecting portion between the first link 44 and the annular member 46, that is, the pivot point P54 is rotated along an imaginary circle 66 centered on the point P2. The flywheel 14
Along with the uniform rotational movement of the rotary shaft 40 and the arm 42, the rotating shaft 40 and the arm 42 perform a uniform rotational movement around the rotational axis P1.
The annular member 46 rotates at an inconstant speed around the axis P2. Therefore, the crankshaft 16 is connected to the flywheel 14.
Along with the constant rotational movement of the motor, the rotational movement of the rotary axis P1 is performed at an inconstant speed around the rotational axis P1.

When uniform rotational motion is converted to inconstant rotational motion, the arm 42 and the first link 44, the first link 44 and the second link 48, and the second link 48 and the lever 50 are , axes P52, P56 and P5, respectively
8 and the first link 44 undergoes an angular rotation relative to the annular member 46 about its pivot point P54. This absorbs the difference in the angular velocity of the lever 50, which rotates at an inconstant velocity, with respect to the angular velocity of the rotating shaft 40 and arm 42, which rotate at a constant velocity.

Lever 50 with respect to rotation angle of rotation shaft 40
The rotational speed of the slide 34, that is, the reciprocating speed of the slide 34 is determined by the distance between the axes P1 and P2 (the amount of eccentricity), the axis P1,
Distance between P52, distance between axes P53 and P54, distance between axes P54 and P56, distance between axes P56 and P58, distance between axes P1 and P58, angle of line connecting axes P1 and P2 with respect to the horizontal line, etc. It depends.

The axis of rotation of the lever 50 may be an axis extending parallel to and separated from the axis of rotation of the rotating shaft 40. The vertical position, reciprocating speed, and acceleration of the slide 34 relative to the rotation angle of the rotating shaft 40 are shown by curves A, B, and C in FIG. 7, respectively.

As is clear from FIG. 7, in the above embodiment, the bottom dead center of the slide 34 is reached when the rotating shaft 40 has rotated approximately 200 degrees, and the slide 34 gradually descends and rapidly rises. That is, the uniform rotational motion of the flywheel 14 is converted by the power transmission device 12 into an inconstant rotational motion that causes the slide 34 to gradually lower and then rapidly rise.

According to the power transmission device 12, the flywheel 14, the rotating shaft 40, and the arm 42 have a common rotational axis. The unbalanced force acting on the device is small, and the device becomes smaller and simpler. Furthermore, since the lever 50 is attached to the crankshaft 16, it can be easily assembled into an existing press machine.

If the unbalanced force caused by the rotation of the arm 42, first link 44, cylindrical member 46, second link 48, and lever 50 becomes a problem, a counterweight is attached to the rotating shaft 46 or the crankshaft 16. Alternatively, a disk may be used in place of the arm 42 and lever 50. Furthermore, instead of directly attaching the lever 50 to the crankshaft 16, an output shaft to which the lever 50 is attached may be provided and the output shaft may be connected to the crankshaft. It may also be rotated around a rotation axis.

Instead of pivotally connecting the second link 48 to the first link 44, the second link 48 is connected to the tubular member 4.
6 , or both the first link 44 and the tubular member 46 , ie, the pin 54 .

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of a press machine equipped with a power transmission device of the present invention.

FIG. 2 is a right side view showing an embodiment of the power transmission device of the present invention.

FIG. 3 is an enlarged cross-sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is an enlarged cross-sectional view taken along line 4-4 in FIG. 2;

FIG. 5 is an enlarged cross-sectional view taken along line 5-5 in FIG. 2;

FIG. 6 is an enlarged cross-sectional view taken along line 6-6 of FIG. 2;

FIG. 7 is a diagram showing the relationship between the vertical position, reciprocating speed, and acceleration of the slide with respect to the rotation angle of the rotating shaft.

[Explanation of symbols]

10 Press machine 12 Power transmission device 14 Flywheel 16 Crankshaft 22 Frame 24 Motor 30 Clutch and brake mechanism 34 Slide 40 Rotating shaft (first transmission means) 42 Arm (second transmission means) 44 First link (second transmission means) 3 transmission means) 46 Cylindrical member (third transmission means) 48 Second link (fourth transmission means) 50 Lever (fifth transmission means) 52-58 Pivot connection pin 56 Virtual circle P1 Rotation axis of rotation shaft P2 Rotation center of cylindrical member P54 Pivot point

Claims (6)

[Claims] 1. A power transmission device for a press machine that transmits the rotation of a flywheel to a crankshaft, the first transmission means being rotated in response to the rotation of the flywheel; and the first transmission means. a second transmission means rotated by the rotation of the second transmission means and having an essentially common axis of rotation with the first transmission means; a second transmission means pivoted to the second transmission means to be rotated by the rotation of the second transmission means; a third transmission means connected to the first transmission means, the third transmission having a pivot point rotatably moved along an imaginary circle centered on a point eccentric to the rotational axis of the first transmission means; means, a fourth transmission means pivotally connected to said third transmission means to be rotated by rotation of said third transmission means; and said fourth transmission means to be rotated by rotation of said fourth transmission means. A power transmission device for a press machine, comprising: a fifth transmission means pivotally connected to a fourth transmission means, and a fifth transmission means connected to the crankshaft for rotating the crankshaft. 2. The power transmission device according to claim 1, wherein the axis of rotation of the first transmission means essentially coincides with the axis of rotation of the flywheel. 3. The third transmission means includes a link that is pivotally connected to the first transmission means, and a link that is pivotally connected to the link on a virtual circle centered on the eccentric point. 3. The power transmission device according to claim 1, further comprising: a rotatable annular member whose center of rotation is essentially the eccentric point. 4. The fifth transmission means is mounted on the crankshaft such that the axis of rotation thereof essentially coincides with the axis of rotation of the crankshaft. Power transmission device. 5. The fifth transmission means having an essentially common axis of rotation with the first transmission means,
5. The power transmission device according to 2, 3 or 4. 6. The first transmission means rotatably supports the flywheel and relatively unrotatably supports a clutch/brake mechanism provided in association with the flywheel. , 2, 3, 4 or 5.