JPH11156598A - Slide stroke variable device of press machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable various kinds of press operations by one press machine having a toggle mechanism. SOLUTION: An upper link constituting a toggle mechanism is extended towards the opposite side of a supporting point shaft 20 to be a swing link 21, and a crankshaft 27 is installed at the rear of the tip part of the swing link 21. A supporting point pin 25 provided in a connecting rod 28 being connected with a decentered part 26 of the crank shaft 27 is slidably engaged with an arch-shaped groove 24 of the swing link 21. The piston of an oil hydraulic cylinder arranged inside the swing link 21 is connected to the ring engaged with the supporting point pin 25, so that the position of the supporting point pin 25 can be switched to the position P near the supporting shaft 20 and the position Q far from the shaft. Also, the swing angel of the swing link 21 is varied due to the rotation of the crankshaft 27 so as to make the slide stroke variable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for varying the slide stroke of a press machine, and is effective when it is desired to make the slide stroke of a press machine using a toggle mechanism variable.

[0002]

2. Description of the Related Art A press machine using a toggle mechanism for driving a slide up and down and having a variable slide stroke is known as a coining press 1 shown in FIG. The coining press 1 is composed of a connecting rod 6 connected to an eccentric shaft 5 of a crankshaft 4 that is rotationally driven via a gear group 3 by a drive source 2, and includes a toggle link 7 and a toggle lever 8.
To move the slide 9 up and down, and the toggle link 7
The mover 10 having the upper end connected thereto is moved up and down a little distance by moving the wedge 12 right and left by the screw mechanism 11, and the position of the bottom dead center of the slide 9 is moved slightly up and down.

[0003] In another example of the prior art, FIG.
The upper end of the toggle link 7 is connected to the frame of the press machine so as to be movable left and right, and the position of the bottom dead center of the slide 9 is slightly moved up and down.

[0004]

SUMMARY OF THE INVENTION The above-mentioned prior art is
It relates to a coining press and the like, and the movement of the bottom dead center position may be small and is suitable for coining.However, if this press machine is used for other molding, the height of the product, the molding height It is not suitable to increase the productivity by changing the slide stroke to a large or small size depending on the depth of the material, the shape of the material, and the like.

[0005] There has been no other press machine using a toggle mechanism with a variable slide stroke.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a variable slide stroke device of a press machine which is capable of changing a slide stroke and suitable for various press operations.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a press machine which raises and lowers a slide by bending and extending a connecting portion between an upper link and a lower link of a toggle mechanism. A swing link formed by extending the upper link that swings around the fulcrum axis on the opposite side of the fulcrum axis, and a position changeable in the longitudinal direction of the swing link at the tip of the extended side of the swing link Fulcrum pin, and a crankshaft that is rotatably provided on the frame of the press machine behind the fulcrum pin and has an eccentric portion connected to the fulcrum pin and a connecting rod, and the swing link is changed by changing the position of the fulcrum pin. The swing stroke is switched to make the slide stroke variable.

The shape of the swing link is not a straight line but a bell crank shape. In this case, a fulcrum pin is provided at one end of the bell crank that swings around a fulcrum axis of the frame of the press machine, and the swing angle of the bell crank is changed by changing the position of the fulcrum pin as described above. To make the slide stroke variable.

[0009]

1 to 5 show a first embodiment of a variable slide stroke device for a press machine according to the present invention. 1 to 3 show a press machine 15 provided with a variable slide stroke device. An upper end of a slide 17 provided on a frame 16 of a press machine 15 so as to be able to move up and down and a lower end of a link 18 are rotatably connected by a pin 19 oriented in a horizontal direction. Above it, a fulcrum shaft 20 provided on the frame 16 of the press machine 15 in the horizontal direction supports a central portion of a linearly long swinging link 21 rotatably,
The lower end of the oscillating link 21 and the upper end of the link 18 are rotatably connected by a pin 22 which faces in the horizontal direction. The lower end of the oscillating link 21 is opened in a U-shape at the lower side, and FIG.
As shown in the figure, the upper end of the link 18 is inserted into the U-shaped portion and connected by the pin 22.

The upper end of the oscillating link 21 is opened upward in a U-shape in the same manner as the lower end, and as shown in FIG.
The hydraulic cylinder 23 is located between the bottom of the U-shaped portion and the fulcrum shaft 20.
Are provided upward, and a piston 23 </ b> A that protrudes and retracts by hydraulic pressure in the hydraulic cylinder 23 is provided. On both side surfaces of the upper U-shaped portion, arc-shaped grooves 24, 24 centering on the center of the crankshaft 27 shown in FIG. 1 are provided. Groove 24,
24 has a fulcrum pin 25 that penetrates it in the horizontal direction and is slidably provided along the grooves 24. A connecting rod in which a crankshaft 27 having an eccentric portion 26 is rotatably provided on the frame 16 of the press machine 15 behind the upper end of the swing link 21 on the frame 16 of the press machine 15 and one end of which is connected to the eccentric portion 26 As shown in FIG. 3, the other end of the pin 28 has a bifurcated shape with a horizontal front facing, and is connected to both ends of the fulcrum pin 25.

That is, as shown in FIGS. 2 and 3, the fulcrum pin 25 is connected at both ends to a connecting rod 28,
The inside thereof penetrates the grooves 24 of the swing link 21, and the center portion penetrates a ring 29 connected to a piston 23 </ b> A provided inside the hydraulic cylinder 23. Therefore, when the pressure fluid is supplied / discharged to / from the hydraulic cylinder 23 and the fulcrum pin 25 is moved via the ring 29 to a position shown by a dotted line far from the fulcrum shaft 20 shown in FIG. By the rotation of the crankshaft 27, the swing angle of the swing link 21 driven to swing by the eccentric portion 26, the connecting rod 28 and the fulcrum pin 25 changes.

As shown in FIG. 1, the crankshaft 27 has
A flywheel 30 having a clutch / brake (not shown) is provided, and the flywheel 30 is driven to rotate by a main motor 31 to swing the swing link 21 and raise and lower the slide 17 via the link 18.

FIG. 4 shows a state in which the fulcrum pin 25 is moved along the grooves 24, 24 of the oscillating link 21 to a position P close to the fulcrum shaft 20 and a position Q far from the fulcrum shaft 20. FIG.
As shown in FIG. 4A, when the fulcrum pin 25 is at a position P close to the fulcrum shaft 20, the swing angle of the swing link 21 is large and the slide stroke is 65 mm, and as shown in FIG. When the pin 25 is moved by 20 mm to the far position Q, the swing angle of the swing link 21 becomes small, and the slide stroke becomes as small as 45 mm.

FIG. 5 shows slide stroke diagrams p and q when the fulcrum pin 25 is located at a position P near and a position Q far away.
Is shown. When the stroke of the diagram p is 65 mm, the bottom dead center is 190 °, and when the stroke of the diagram q is 45 mm,
The bottom dead center is 195 °, and the position of the bottom dead center is slightly shifted due to a change in the swing angle of the swing link 21, but this does not pose a problem in practical use.

Next, FIGS. 6 and 7 show a second embodiment of the present invention in which the linear swing link 21 in the first embodiment has a bell crank shape bent at the fulcrum shaft 20 portion. .

As shown in FIG. 6 and FIG.
A pin 19 that horizontally turns the upper end of the slide 17 and the lower end of the link 38 provided on the frame 36
And rotatably connected. Above it, press machine 3
A fulcrum shaft 40 provided on the frame 36 of FIG.
, The bell crank 52 is rotatably supported, and one of the two fulcrums of the bell crank 52 is rotatably connected to the link 38 by the pin 42 as in the first embodiment.

The other fulcrum portion of the bell crank 52 is provided with an arc-shaped groove 44 centered on a crankshaft 47 having an eccentric portion 46, and penetrates the same horizontally as in the first embodiment. A fulcrum pin 45 is slidably provided along the groove 44, and the other end of the connecting rod 48 is rotatably connected to the fulcrum pin 45. A hydraulic cylinder 43 for moving a fulcrum pin 45 via a ring 49 is provided at a portion of the bell crank 52 supported by the fulcrum pin 40, as in the first embodiment.
A piston 43A is provided in the lower part 3 and protrudes downward by hydraulic pressure.

Accordingly, the fulcrum pin 45 is moved by supplying / discharging the hydraulic pressure to / from the hydraulic cylinder 43, and the swing angle of the bell crank 52 is changed as in the first embodiment. As shown in FIG. 6, a flywheel 30 having a clutch and a brake (not shown) is provided on a crankshaft 47, which is rotationally driven by a main motor 31 to swing a bell crank 52, and To raise and lower the slide 17. As described above, by maintaining the positional relationship with the crankshaft 47 appropriately, the same result as that of the above-described first embodiment can be obtained even with the bell crank 52.

[0019]

As is apparent from the above description, according to the present invention, the toggle mechanism is provided by making the fulcrum pin, which is the connecting shaft between the swing link and the connecting rod, movable in the longitudinal direction of the swing link. The slide stroke of the press machine can be switched between long and short, and the range of press work that can be performed by one press machine can be expanded. The same effect as described above can also be obtained when the swing link has a bell crank shape.

[Brief description of the drawings]

FIG. 1 is a side view of a main part of a press machine having a variable slide stroke device according to a first embodiment of the present invention.

2 is a cross-sectional view of FIG.

FIG. 3 is a cross-sectional view of FIG.

FIG. 4A is an explanatory view of a slide stroke when the distance between the fulcrum pin and the fulcrum shaft is small when the fulcrum pin is shifted in the first embodiment of the present invention; Illustration of slide stroke

FIG. 5 is a slide stroke diagram according to the first embodiment of the present invention.

FIG. 6 is a side view of a main part of a press machine having a variable slide stroke device according to a second embodiment of the present invention.

FIG. 7A is an explanatory view of a slide stroke when the distance between the fulcrum pin and the fulcrum axis is small when the fulcrum pin is shifted in the second embodiment of the present invention. Illustration of slide stroke

FIG. 8 is an explanatory view of a conventional example.

[Description of Signs] 15 and 35 are press machines, 16 and 36 are frames, 17
Is a slide, 18, 38 are links, 19, 22, 42 are pins, 20, 40 are fulcrum shafts, 21 is a swing link, 23,
43 is a hydraulic cylinder, 23A and 43A are pistons, 2
4 and 44 are grooves, 25 and 45 are fulcrum pins, 26 and 46 are eccentric parts, 27 and 47 are crankshafts, 28 and 48 are connecting rods, 29 and 49 are rings, 30 is a flywheel, 31 is a main motor, 52 is a bell crank.

Claims (2)

[Claims] 1. A press machine which raises and lowers a slide by bending and extending a connecting portion between an upper link and a lower link of a toggle mechanism. (A) The upper link swinging around a fulcrum axis of a frame of the press machine is provided with the fulcrum. (B) an oscillating link formed by extending to the opposite side of the shaft, and (b) a fulcrum pin provided at the end of the extending side of the oscillating link so as to be changeable in the longitudinal direction of the oscillating link. A crankshaft that is rotatably provided on the frame of the press machine behind the fulcrum pin and has an eccentric portion connected to the fulcrum pin and a connecting rod; A variable slide stroke device for a press machine, wherein a slide angle is variable by switching a moving angle. 2. A slide stroke varying device for a press machine according to claim 1, wherein said swing link is formed in a bell crank shape.