JP2002346798A - Driving device for crank press - Google Patents

Abstract

PROBLEM TO BE SOLVED: To overcome such a problem that the speed-up of press work machin ery is restricted, the constitution of the press work machinery is made compli cated and becomes larger or the like in the press work machinery which is driven with a crank mechanism. SOLUTION: A vertical motion of the crank mechanism is transmitted to a slide through a link mechanism. The link mechanism is provided with rocking base shafts 21A, 21B, rocking links 22A, 22B, rocking pivots 23A, 23B and lever links 24A, 24B which are pivotally connected to these rocking pivots and a connecting pivot 16 on one side of which is rockable like a balance is pivotally connected to the linearly moving connecting rod 13 of the crank mechanism and connecting pivots 25A, 25B on the other side of which are pivotally connected to slide driving links 41A, 41B. A balance weight 15 is provided on the straight advancing connecting rod 13 attachably and detachably and the moments of mutual forces which act on the connecting pivot 16 and the connecting pivots 25A, 25B are balanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crank mechanism for vertically moving a connecting rod by rotating a crankshaft and a link mechanism for transmitting the vertical movement of the crank mechanism to the slide by leverage. The present invention relates to a crank press driving device that moves an upper die up and down.

[0002]

2. Description of the Related Art As a conventional technique according to the present invention, for example, a power transmission device for transmitting a rotational motion of a crankshaft to a slide and a balancing device for balancing an unbalanced inertial force caused by the motion of the slide are disclosed. Japanese Patent Application Laid-Open No. Hei 7-132400 (hereinafter referred to as "prior art publication") related to a press equipped with the same.
Is known. In the following description of this prior art, the reference numerals described in the official gazette are used, and therefore, the reference numerals of the present invention partially overlap. This is applied only to the column of “Issues to be done”.

As shown in FIG. 7, a power transmission device 30 provided in a press 10 according to the invention disclosed in this prior art publication has a frame 1 having a longitudinal center portion pivoted by pivots 58,58.
4 and a first link 38a, 38a pivotable about the pivots 58, 58, and a first link 38 at the upper end.
a, 38 a pivotally connected to one end (pivots 54, 54) and the lower end is connected to the slide 20 via the rod 22.
A connecting piece (connecting rod) 32 having links 38b, 38b and reciprocating by rotation of the crankshaft 16, and pivoting ends of fourth links 36b, 36b, one end of which is pivotally supported at a fixed position, are pivoted by pivots 46, 46. Third links 36 a, 36 pivotally connected to the connecting piece 32 at one end pivotally connected to the center and serving as a swing fulcrum.
a, one end of which is pivotally connected to the other ends of the third links 36a, 36a and the other ends of which are the first links 38a, 38a and the second link 3
8b, 38b are connected to each other by pivots 54, 54. The first links 38a, 38a and the second links 38b, 38 are rotated by rotation of the crankshaft 16.
b and the slide 20 is reciprocated up and down by bending and extending the b.

[0004] The other balancing device 84 is a frame 1
Balance weight 86 supported so as to be able to reciprocate up and down on 4
A power transmission device 30 having a lower end portion connected to the first link 38a, the other end portion (the pivot 94) of the first link 38a, and an upper end portion connected to the balance weight 86.
First link 38a, 38a and second link 38b, 38
b is bent and stretched, so that the connecting links 90, 90
, The balance weight 86 is reciprocated up and down. By preventing the balance weight 86 from reciprocating in the horizontal direction, vibration of the press machine 10 in the horizontal direction due to the reciprocation of the balance weight 86 is prevented.

[0005]

In order to increase the speed of the press machine, the unbalanced inertial force caused by the vertical movement of the slide is balanced, and the reciprocating movement and the oscillating movement are performed by the rotational movement of the crankshaft. It is required to reduce the total mass of the movable part. However, the invention of the above prior art publication has a configuration in which the total mass of the movable portion is increased.
That is, the pivots 58, 58 of the first links 38a, 38a
With the mass of the slide 20 and the power transmission device 30 acting as a fulcrum for the moment of inertia force acting on one end (the pivots 54, 54) of the power transmission device 30 and the power transmission system between the crankshaft 16 and the slide 20. Balance weight 86 installed
The balance of the inertia force acting on the other ends (the pivots 94, 94) is balanced by the mass of the slide 20, and the unbalanced inertia force resulting from the vertical movement of the slide 20 is balanced. In other words, the forces acting on the pivots 54, 54 are configured so that the inertial force due to the mass of the slide 20 and the inertial force due to the mass of the power transmission device 30 act in the same direction and act together.

Therefore, when considering the moments about the pivots 58, 58, the inertial force due to the mass of the power transmission device 30 and the inertial force due to the mass of the slide 20 cannot only be canceled, but are added together. The mass of the weight 86 requires extra mass to correspond to the inertia of the slide 20 and the power transmission device 30. As a result, there has been a problem that the speed of the press machine is restricted because the total mass of the movable part increases.

Further, the arrangement position of the balance weight 86 is located outside the power transmission system between the crankshaft 16 and the slide 20 (upper part of the power transmission device 30), requiring a large number of links, Due to factors such as the need to securely support the balance weight 86 and the rod 22 of the slide 20 in order to absorb horizontal vibrations due to the component forces of the multiple links that bend and extend, the configuration of the press machine is complicated and large. In addition, there is a problem that the manufacturing cost is high.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and an object of the present invention is to provide a press machine driven by a crank mechanism in which an arrangement position of a balance weight is a power source. Attempts to solve problems such as the limitation of high-speed press machines due to being located outside the transmission system and the problem of complicated and large-sized press machines and high manufacturing costs Things.

[0009]

In order to solve the above-mentioned problems, a first aspect of the present invention is directed to a crank mechanism for vertically moving a connecting rod by rotating a crankshaft, and a vertical movement by the crank mechanism. A link mechanism that moves the slide up and down by leverage, and a drive device of a crank press that reciprocates an upper die provided on the slide, wherein the link mechanism is a symmetrical position that sandwiches the vertical movement axis of the crank mechanism. Each link mechanism includes a swing base shaft supported by a frame, a swing link pivotally supported by the swing base shaft and capable of pendulum movement, and a swing end supported by the swing end of the swing link. And one of the crank-side ends pivotally connected to the pivot shaft and swingable like a balance is pivotally connected to the connecting rod of the crank mechanism and the other slide-side end is provided. The upper part of the slide is provided with a lever link pivotally connected to a slide drive link of a bearing, and the mass acting on each crank side end is provided with the pivotal connection part of each swinging pivot of the pair of lever links as a fulcrum of the lever action. And the moment of the inertial force due to the mass acting on each slide side end is balanced.

According to the first aspect of the present invention, a pair of lever links that can swing like a balance are provided, the crank-side end of each lever link is pivotally connected to the connecting rod of the crank mechanism, and the slide-side end is connected. Since it is connected to the top of the slide,
By equalizing the moment of the inertial force due to the mass of the crank mechanism acting on the crank end and the moment of the inertial force due to the mass of the slide and upper die acting on the slide end in the opposite direction, The moments of the mutual inertial forces can be balanced by using the pivot point between the crank-side end and the slide-side end as a fulcrum of the lever action, and can balance the unbalanced inertial force caused by the vertical movement of the slide. .

Since the moments of the mutual inertial forces acting on the crank side end and the slide side end of each lever link are offset in the power transmission system between the crank shaft and the slide, the movable part Can be balanced without increasing the total mass of. Therefore, since the inertial load on the crankshaft is small, the speed of the press machine can be easily increased. In addition, the press machine is composed of a small number of links, and there is no horizontal vibration due to the link that bends and stretches, so that the press machine can be simplified and downsized.

In the crank mechanism according to the second aspect of the present invention, the moment of inertial force due to the mass acting on the crank side end of each lever link of the link mechanism is applied to the slide side end of each lever link. It is a configuration that can be adjusted according to the moment of inertia force due to the acting mass,
A balance weight is detachably provided on the connecting rod of the crank mechanism, and by adjusting the mass of the balance weight, the balance weight acts on each crank side end as a pivot point of the lever link as a fulcrum of the lever action. The moment of the inertial force due to the mass of the crank mechanism and the balance weight is balanced with the moment of the inertial force due to the mass of the slide and the upper die acting on each slide side end.

According to the second aspect of the present invention, the connecting rod of the crank mechanism is provided with a detachable balance weight. Therefore, even if the mass of the balance weight changes due to replacement of the upper die, the mass of the balance weight is reduced. By making adjustments to equalize the moment of inertia due to the mass of the crank mechanism and the balance weight and the moment of inertia due to the mass of the slide and upper die acting in the opposite direction, the mutual inertia force is reduced. The moments are balanced,
Unbalanced inertial force caused by the vertical movement of the slide can be balanced.

Since the balance weight is disposed inside the power transmission system between the crankshaft and the slide, the weight can be reduced, and the total weight of the movable parts can be reduced to a minimum. Can be done. Therefore, as in the invention according to the first aspect, the speed of the press machine can be increased, and the press machine can be simplified and downsized.

The link mechanism according to the third aspect of the present invention is configured such that the position of the bottom dead center of the slide can be adjusted, and each of the swing base shafts is supported by a frame and is rotatable. And an eccentric shaft portion that pivotally supports the end of each of the swing links with an axis eccentric with respect to the support shaft portion, and is integrally formed with each other, and each support shaft portion of each of the swing base shafts is formed. A pivoting shaft rotating means for synchronously rotating is provided, and the eccentric shafts are moved up and down by rotating each of the pivoting shafts by a predetermined angle by the pivoting shaft rotating means. The vertical position of the swing center at which the dynamic link makes a pendulum motion is adjusted.

According to the third aspect of the invention, each swing base shaft includes a support shaft portion rotatably supported by the frame and an eccentric shaft portion pivotally supporting an end of each swing link. 3. A press machine according to claim 1 or 2, wherein a swing base shaft rotating means which is integrally formed and synchronously rotates each bearing shaft portion of each swing base shaft is provided. By rotating each swing base shaft by a predetermined angle by the moving means, the swing center of each swing link can be adjusted in the vertical direction. That is, the position of the bottom dead center of the upper die provided on the slide can be easily adjusted corresponding to the configuration of the die.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a drive device for a crank press according to the present invention will be described below with reference to FIGS. 1 is a vertical sectional view taken along the line AA of FIG. 2 showing a crank mechanism and a link mechanism constituting the drive device. FIG. 2 is a vertical sectional view taken along the line BB of FIG. FIG. 4 is a sectional view taken along the line CC of FIG.
Is a cross-sectional view taken along the line DD of FIG. 1 showing a main part of the link mechanism;
FIG. 5 is a cross-sectional view taken along the line EE of FIG. 1 showing a connecting portion with the slide.

The driving device of the crank press is shown in FIGS.
A crank mechanism 10 for vertically moving a connecting rod (in this example, composed of a swinging connecting rod 12 and a straight connecting rod 13) by the rotational movement of a crankshaft 11 shown in FIG.
A link mechanism 20 for vertically moving the slide mechanism, and a pivoting shaft rotating means 30 capable of adjusting the bottom dead center position of the slide 4.
The upper die (not shown) provided on the slide 4 is reciprocated up and down. As the upper die reciprocates up and down, press work is performed with a lower die (not shown) provided on the bolster 5.

First, a crank mechanism 10 for vertically moving a connecting rod includes a rotatable crankshaft 11, a connecting rod (a swinging connecting rod 12 and a vertically movable connecting rod 13) which can move vertically, and a balance weight 1
5 and 15. The crankshaft 11 has an eccentric shaft portion 11c having an axis eccentric with respect to the rotating base shaft portions 11a and 11b on both sides, which is integrally formed at a central portion. It is rotatably supported by bearings. The swing connecting rod 12
The upper end is supported by the eccentric shaft 11c of the crankshaft 11, and moves up and down by the eccentric rotation of the eccentric shaft 11c.

The straight connecting rod 13 has a U-shaped groove 13a formed at the upper end as shown in FIG. 2, and a connecting shaft 14 is fixed to the U-shaped groove 13a. Is pivotally connected at its lower end.
The middle body portion of the straight connecting rod 13 is vertically movably inserted along a sliding guide provided on the frame 1, and the balance weights 15, 15 shown in FIGS.
Are replaceably fastened. A connecting pivot 16 to be described later is pivotally supported at an intermediate portion between the middle body and the lower end of the straight connecting rod 13.

The crank mechanism 10 constructed as described above
When the crankshaft 11 is rotated via the pulley 3 by the rotation drive of the motor 2, the oscillating connecting rod 12 swings up and down around the connecting shaft 14 due to the eccentric rotational movement of the eccentric shaft 11 c. Exercise. Due to the vertical movement of the swinging connecting rod 12, the rectilinear connecting rod 13 is rotated by the rotating base shafts 11 a and 11 b of the crankshaft 11 and the eccentric shaft 11.
It reciprocates up and down depending on the eccentricity with c.

Next, as shown in FIGS. 1, 3 and 4, the link mechanism 20 for moving the slide 4 up and down comprises a pair of swing base shafts 21A and 21B and a pair of swing bases 21A and 21B each capable of pendulum movement. Dynamic links 22A, 22A and 22B, 22B
And a pair of pivot links 23A, 23B, and a pair of lever links 24A, 24A and 24B, 24B each of which can pivot in a balance-like manner.

The pair of swing base shafts 21A and 21B are provided in the same shape at symmetrical positions with respect to the vertical movement axis of the straight connecting rod 13 shown in FIG. Swing base shaft 2 shown in FIG.
1A includes rotating base shaft portions 21a, 21b, 21 having the same axis.
eccentric shaft portions 21 having the same phase and the same amount of eccentricity with respect to e
c and 21d are integrally formed at respective intermediate positions of the rotation base shaft portions 21a, 21b and 21e, and the rotation base shaft portions 21a, 21b and 21e of the swing base shaft 21A are rotated by bearings provided on the frame 1. It is movably supported. The swing base shaft 21B is also provided in the same manner as the swing base shaft 21A, and all the eccentric shaft portions have the same phase relationship.

One swing link 22 shown in FIGS.
A, 22A are eccentric shaft portions 21c, 21 of the swing base shaft 21A.
d pivots the respective upper ends, and the other swing link 22
The upper ends of the swing base shafts 21B and 22B have the same configuration.
The eccentric shaft part is pivotally supported. A pair of swing pivots 23A,
23B is a swing pivot 23A, and one swing link 22A,
Each swing end (lower end) of the swing shaft 22A
At B, the other swing links 22B, 22B are fastened so as to connect the respective swing ends.

A pair of lever links 24A, 24A and 2
4B and 24B are each formed in a balancing rod shape. Each of the lever links 24A, 24A has a center portion in the shape of a balance rod, and each of the pivot links 22A, 22A is pivoted by a pivot shaft 23A.
A is pivotally connected to A and swings in a balance-like manner around the swing pivot shaft 23A. Also, the other lever links 24B, 24B
Similarly, the other swing link 22 is moved by the swing pivot 23B.
B and 22B, and swings like a balance around the swinging pivot 23B.

Each of a pair of lever links 24A, 24A
And 24B, 24B, 24C, and an intermediate portion of the straight connecting rod 13 are connected by a connecting pivot 16. In addition, each of the pair of lever links 24A, 2A
4A and 24B, 24B are connected to each slide-side end of one lever link 24A, 24A by a connecting pivot 25A, and the other lever link 24B, 24B by the connecting pivot 25B.
Are fixed so as to connect the respective slide side ends.

The link mechanism 20 configured as described above is
When the straight connecting rod 13 of the crank mechanism 10 moves up and down, the center position of the pair of swinging pivots 23A and 23B moves on an arc locus centered on the connecting pivot 16 and one of the swinging links 22A and 22A swings. With the base axis 21A as the center,
The other swing link 22B, 22B is connected to the swing base shaft 21.
Each swings around B.

In parallel with these swings, the pair of lever links 24A, 24A and 24B, 24B is moved up and down by the connecting pivot 16 so that one of the lever links 24A, 24A.
Swing about the swing axis 23A as a swing center, and the other lever links 24B, 24B swing like a balance about the swing axis 23B as the swing center, respectively, and a pair of connecting pivots 25A, 25B.
Is moved up and down in the direction opposite to the up and down movement direction of the connecting pivot 16.

Next, below the link mechanism 20, a pair of slide drive links 41A, 41 for driving the slide 4 is provided.
1B and a pair of drive rods 44A and 44B are provided. A pair of slide drive links 41A, 41B
Each upper end shown in FIG. 1 has a pair of connecting pivots 25A,
25B, each lower end is formed in a forked shape (see FIG. 5).

A pair of drive rods 44A and 44B are shown in FIG.
Each upper end shown in FIG. 5 is connected to a pair of slide drive links 41A, 41 shown in FIG.
B is connected between the forked lower ends thereof, and each lower end is fastened to the upper end surface of the slide 4. The middle body portions of these drive rods 44A and 44B are respectively inserted to be vertically movable along sliding guides provided on the frame 1. The tie rods 43, 43 shown in FIG. 5 are fixed to the respective shaft ends of the pair of connection shafts 42A, 42B.
The distance between A and the connecting shaft 42B is fixed at a constant distance.

When the pair of connecting pivots 25A and 25B of the link mechanism 20 move up and down, a pair of slide drive links 41A and 41B and a pair of connecting shafts 42A and 42B are provided.
The slide 4 is vertically guided by the slide guides 6 and 6 via the pair of drive rods 44A and 44B. Further, since the pair of connecting shafts 42A, 42B are held by the tie rods 43, 43, even if there is a slight difference between the left and right link mechanisms shown in FIG. 1, vibration in the left and right directions can be prevented.

Next, as shown in FIGS. 1 and 3, the pivoting base shaft rotating means 30 capable of adjusting the position of the bottom dead center of the slide 4 corresponds to each of the pair of pivoting base shafts 21A and 21B. It comprises worm wheels 31A and 31B provided, a worm shaft 32, and a steering wheel 33.
The pair of worm wheels 31A and 31B have the same tooth profile engraved on the outer circumference, respectively.
And a worm wheel 31B is similarly keyed to the swing base shaft 21B.

The worm shaft 32 is mounted on the frame 1 on an axis perpendicular to the axis of the pair of worm wheels 31A and 31B.
Worm portions 32a and 32b having worm teeth formed thereon are integrally formed at positions where the worm shafts can be engaged with the upper portions of the pair of worm wheels 31A and 31B. Handle wheel 3 for rotating 32
3 is fixed.

Oscillating base shaft rotating means 3 constructed as described above
0 is the worm shaft 32 due to the turning operation of the steering wheel 33.
Is rotated, the pair of worm wheels 31A and 31B meshing with the worm portions 32a and 32b are respectively rotated by the same rotation angle together with the pair of swing base shafts 21A and 21B. By this rotation, the eccentric shaft portion 2 of the swing base shaft 21A is formed.
1c and 21d move upward or downward because they are eccentric with respect to the pivot base shafts 21a, 21b and 21e.
Similarly, the swing base shaft 21B simultaneously moves upward or downward by the same amount.

By moving the pair of pivot base shafts 21A, 21B upward or downward, the pair of pivot shafts 23A, 23B together with the pair of pivot links 22A, 22A and 22B, 22B are moved upward or downward. Respectively, the pair of lever links 24A, 24A and 24B, 24B respectively swing upward or downward about the connection pivot 16 as the pivot center, and a pair of connection pivots 25A,
25B is moved upward or downward.

When the pair of connecting pivots 25A and 25B move upward or downward, the pair of slide drive links 41
The slide 4 can be moved upward or downward via the drive rods A, 41B and the pair of drive rods 44A, 44B. That is, the lower dead center position of the slide 4 can be adjusted upward or downward by rotating the handle wheel 33.

Next, the operation of balancing the unbalanced inertial force caused by the vertical movement of the slide 4 will be described with reference to FIG. FIG. 6 is an enlarged view of FIG. 1 showing an operation relationship between the crank mechanism 10 and the link mechanism 20, and a left half portion shows a bottom dead center position of the slide 4,
The right half shows the top dead center position.

When the crankshaft 11 is rotated by 180 degrees from the top dead center position of the slide 4 shown in the right half of FIG. 6 as shown in the left half, the swinging connecting rod 12 is rotated by the rotation of the eccentric shaft 11c. The connecting pivot 16 moves from the lower end position to the upper end position via the connecting shaft 14 and the straight connecting rod 13.
At this time, the lever link 24A swings counterclockwise with the swing pivot 23A as a swing fulcrum, and the connection pivot 25A has a direction opposite to the direction in which the inertial force due to the mass acting on the connection pivot 16 acts. The inertial force due to the mass acts on the body.
At this time, the inertial force due to the mass also acts on the connecting pivot 25B in a direction opposite to the direction in which the inertial force due to the mass acting on the connecting pivot 16 acts.

Further, from the bottom dead center position of the slide 4 shown in the left half of FIG.
When rotated by 80 degrees, the connection pivot 16 moves from the upper end position to the lower end position, the lever link 24B swings counterclockwise with the swing pivot 23B as a swing fulcrum, and the connection pivot 25B The inertial force due to the mass acts in a direction opposite to the direction in which the inertial force due to the mass acting on the body acts.
At this time, the inertial force due to the mass also acts on the connecting pivot 25A in a direction opposite to the direction in which the inertial force due to the mass acting on the connecting pivot 16 acts.

Therefore, the moment of the inertial force due to the mass of the crank mechanism 10 acting on the connecting pivot 16 and the moment of the inertial force due to the mass of the slide 4 and the upper die (not shown) acting on the connecting pivots 25A and 25B are balanced. By doing so, the unbalanced inertial force caused by the vertical movement of the slide 4 can be balanced. In order to adjust the moments of the inertial forces to be balanced, the adjustment can be performed by adjusting the mass of the balance weight 15.

It should be noted that the drive device for a crank press according to the present invention is not limited to the above-described embodiment at all, and can be configured in various forms without departing from the gist of the present invention.

[0042]

As described above, the present invention has the following effects.

According to the first aspect of the present invention, a pair of swingable lever links is provided in a balance-like manner, and the inertial force due to the mutual mass acting on the crank side end and the slide side end of each lever link is provided. Since the moments are balanced, the moments of the inertial force due to the mutual mass cancel each other out in the power transmission system between the crankshaft and the slide, and can be balanced without increasing the total mass of the movable part. Therefore, since the inertial load on the crankshaft is small, productivity can be improved by increasing the speed of the press machine. Further, since the link is composed of a small number of links and there is no horizontal vibration due to the link that bends and extends, the manufacturing cost can be reduced by simplifying and reducing the size of the press machine.

According to the second aspect of the present invention, the connecting rod of the crank mechanism is provided with a replaceable balance weight, and the mass of the balance weight is adjusted even if its mass changes by replacing the upper die. By doing so, the moment of inertia force due to the mutual mass acting on the crank side end and the slide side end of each lever link is balanced, so that high-speed operation of the press machine corresponding to various dies is easy. it can. In addition, since the setup can be quickly changed by replacing the mold, the work efficiency can be improved.

According to the third aspect of the present invention, each swing base shaft includes a support shaft portion rotatably supported by the frame and an eccentric shaft portion pivotally supporting an end of each swing link. The swing shafts are integrally formed, and swing shaft rotating means for synchronously rotating the respective support shafts of the swing shafts are provided, and by adjusting the swing center of each swing link in the vertical direction, the slide shaft is formed. Since the position of the bottom dead center of the provided upper die is adjusted, high-speed operation of the press machine corresponding to the configuration of the die can be easily performed. In addition, since the bottom dead center position can be quickly adjusted, the work efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a crank mechanism and a link mechanism constituting a drive device for a crank press according to the present invention, and is a front view in a longitudinal section taken along line AA of FIG.

FIG. 2 is a side view of the same, as viewed in the direction of arrows BB in FIG.

FIG. 3 is an explanatory view showing the pivoting shaft rotating means, and is a cross-sectional view taken along the line CC of FIG. 1;

FIG. 4 is an explanatory view showing a main part of the link mechanism, and is a cross-sectional view taken along the line DD of FIG. 1;

5 is an explanatory view showing a connection portion with a slide, and is a cross-sectional view taken along the line EE of FIG. 1;

FIG. 6 is an explanatory view showing the operation relationship between the crank mechanism and the link mechanism, and is an enlarged view of FIG. 1;

FIG. 7 is an explanatory view of a press according to a conventional technique,
It is the longitudinal section.

[Explanation of symbols]

 Reference Signs List 4 Slide 10 Crank mechanism 11 Crank shaft 12 Swing connecting rod 13 Straight connecting rod 14 Connecting shaft 15 Balance weight 16 Connecting pivot 20 Link mechanism 21A, 21B Swing base shaft 22A, 22B Swing link 23A, 23B Swing pivot 24A, 24B Lever link 25A, 25B Connecting pivot 30 Swing base pivot means 31A, 31B Worm wheel 32 Worm shaft

Claims (3)

[Claims] An upper die provided on a slide is reciprocated up and down by a crank mechanism that moves a connecting rod up and down by rotating the crankshaft and a link mechanism that moves the slide up and down by leverage of the up and down movement of the crank mechanism. A drive device for a crank press to be moved, wherein the link mechanism is constituted by a pair at symmetric positions sandwiching a vertical movement axis of the crank mechanism, each link mechanism includes a swing base shaft supported by a frame, A swing link pivotally supported by a base shaft and capable of pendulum movement, a swing pivot supported at the swing end of the swing link, and a swingable pivotally connected to the swing pivot to form a balance. And a lever link that is pivotally connected to the connecting rod of the crank mechanism and the other slide-side end is connected to a slide drive link of a bearing at the upper part of the slide. The moment of inertial force due to the mass acting on each crank side end and the inertial force due to the mass acting on each slide side end, with the pivot portion of each pivot axis of the pair of lever links serving as a fulcrum of the lever action. A driving device for a crank press, wherein moment is balanced. 2. The crank mechanism according to claim 1, wherein a moment of inertial force due to a mass acting on a crank side end of each lever link of the link mechanism changes an inertial force due to a mass acting on a slide side end of each lever link. It is a configuration that can be adjusted in accordance with the moment, and a balance weight is detachably provided on the connecting rod of the crank mechanism, and the mass of the balance weight is adjusted to adjust the weight of the connecting portion of each lever link. As the fulcrum of the lever action, the moment of the inertial force due to the mass of the crank mechanism and the balance weight acting on each crank side end, and the moment of the inertial force due to the mass of the slide and the upper die acting on each slide side end. The drive device for a crank press according to claim 1, wherein the drive device is balanced. 3. The link mechanism is capable of adjusting a position of a bottom dead center of a slide, wherein each of the swing base shafts is supported by a frame and is rotatable. An eccentric shaft portion for pivotally supporting an end of each of the oscillating links with an eccentric shaft center, and an oscillating shaft for synchronously rotating each bearing shaft of the oscillating shaft; A rotation means is provided, and the respective eccentric shaft portions are moved up and down by rotating the respective oscillating base shafts by a predetermined angle by the oscillating base shaft rotating means. 3. The crank press driving device according to claim 1, wherein the vertical position of the moving center is adjusted.