JPH0715678Y2 - Hydraulic press machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial field of application) The present invention relates to a hydraulic press machine for punching a work.

(Prior Art) Conventionally, there has been known a hydraulic press machine in which a ram is moved up and down by a hydraulic cylinder to cause an upper die and a lower die to cooperate with each other to perform punching on a work.

In this hydraulic press machine, since a large amount of oil flows,
When the oil returned from the hydraulic cylinder to the tank of the hydraulic unit, a metallic noise and vibration called a water hammer was generated. For this reason, in order to eliminate the phenomenon of the water hammer, a means for absorbing a metallic sound by contracting the rubber is provided by providing a rubber hose in the return circuit of the hydraulic circuit in the hydraulic cylinder.

(Problems to be solved by the invention) By the way, with the above-mentioned means of providing a rubber hose in the return circuit of the hydraulic circuit in the hydraulic cylinder, the metallic sound generated by the phenomenon of the water hammer is not completely removed, and the rubber Had a problem that its life was extremely short and maintenance was very difficult.

The object of the present invention is to provide a cylinder type accumulator for pulsation prevention in the return circuit of the hydraulic circuit in the hydraulic cylinder to almost completely eliminate the metallic sound of the phenomenon of water hammer and to prevent pulsation. It is to provide a hydraulic press machine that can be semi-permanently used.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention has a ram (43) via a piston (39) by the operation of a hydraulic cylinder (37).
A hydraulic press machine for vertically pressing a work (W) in cooperation with an upper die (17) and a lower die (19), the cylinder chamber 7 of a hydraulic circuit in the hydraulic cylinder (37). And the return circuit (75,7) connecting the tank (71)
7, 79) is provided with a cylinder type accumulator (81), and when the piston (39) is raised, the oil discharged from the cylinder chamber is removed by the cylinder type accumulator (81).
The cylinder type accumulator (81) is configured so that the pressure of the drained oil is lowered once, and the drained oil gradually flows from the cylinder type accumulator (81) to the tank (71) instead of in a lump form. It is what

(Operation) By adopting the hydraulic press machine of the present invention, the ram is moved up and down by the hydraulic cylinder so that the upper die and the lower die cooperate with each other to press the work. When the ram descends by the hydraulic cylinder and punches up the work, it then rises, and a large amount of oil flows out from the cylinder chamber to the tank in a short time, causing a large pressure and a metallic hammer noise. To do.

At this time, when a part of the return oil enters the pulsation-preventing cylinder type accumulator provided in the return circuit of the hydraulic circuit in the hydraulic cylinder, the high-pressure oil pushes the piston of the accumulator and is relieved by the force of the spring. The pressure of the oil discharged becomes smaller.

Next, when the second wave of return oil enters the accumulator, it collides with the first wave of return oil and a pressure lower than atmospheric pressure is generated. However, since the opposite side of the return oil inlet of the accumulator is released to the atmospheric pressure, here, the oil breathes to relax the pulsating flow and the return oil is returned to the tank.
As a result, the water hammer is almost completely removed, and the life of the accumulator becomes semi-permanent so that the accumulator can be used for cost reduction.

(Embodiment) Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 4, for example, a hydraulic punch press 1 as a hydraulic press machine is integrally configured with a lower frame 3, a column 5 and an upper frame 7 in a gate shape.
Between the lower frame 3 and the upper frame 7, a rotatable lower turret 11 is provided on a shaft 9 provided on the lower frame 3 and a shaft 13 provided downward on the upper frame 7.
A rotatable upper turret 15 is supported on each of them. Moreover, the lower turret 13 and the upper turret 15 are rotated in synchronization with each other.

A plurality of punches 17 as upper molds are mounted on the circumference of the upper turret 15, and a die 19 as a lower mold is mounted on the circumference of the lower turret 13 at a position corresponding to the punches 17. The upper frame 7 is provided with a hydraulic cylinder device 21.

A table 23 movable in the left-right direction (hereinafter referred to as the Y-axis direction) in FIG. 4 is provided on the lower frame 3, and a carriage base 25 is attached to the left end of the table 23. . The carriage base 25 is provided with a carriage 27 which is movable in a direction (hereinafter, referred to as X-axis direction) orthogonal to the paper surface in FIG. A plurality of work clamps 29 that can clamp the work W are attached to the carriage 27.

With the above configuration, the hydraulic cylinder device 21 is actuated on the work W clamped by the work clamp 29 to perform punching.
By moving 17 up and down, desired press working is performed by the cooperation of punch 17 and die 19, and work W is moved by moving the work W in the X-axis and Y-axis directions.
More than one press work will be performed.

As shown in FIG. 1, the punch 17 is attached to the upper turret 15 through a punch holder 31, and the groove 15V formed in the upper turret 15 and the punch holder 3 are attached.
A lifter spring 33 is urged upward with respect to 1 and is interposed, and a stripper spring 35 is urged upward with respect to the punch 17 and the punch holder 31. .

The specific configuration of the hydraulic cylinder device 21 is also shown in FIG. That is, in FIG. 1, a piston 39 is vertically movably mounted on a hydraulic cylinder 37 of a hydraulic cylinder device 21, and a ram 43 is supported by a wrist pin 41 at a lower portion of the piston 39. A striker 47 is attached to the lower end of the ram 43 with a plurality of bolts 45.

Inside the hydraulic cylinder 37, an upper cylinder chamber 49 is formed on the upper side and a lower cylinder chamber 51 is formed on the lower side with a piston 39 as a boundary. An oil passage 53 communicating with the upper cylinder chamber 49 is formed in the upper part of the hydraulic cylinder 37.
A servo valve 57 is connected to 53 via a pipe 55.

A hydraulic pump 61 is connected to the servo valve 57 via a pipe 59. An accumulator 65 is connected to the middle of the pipe 59 via a pipe 63. One end of a pipe 67 is connected to the hydraulic pump 61, and the other end of the pipe 67 communicates with a tank 71 via a filter 69. A drive motor 73 is linked to the hydraulic pump 61.

An oil passage 75 communicating with the lower cylinder chamber 51 is formed in the hydraulic cylinder 37, and the oil passage 75 is communicated with the tank 71 via a pipe 77. A pulsation-preventing cylinder type accumulator 81 is connected in the middle of the pipe 77 via a pipe 79.

With the above configuration, by driving the drive motor 73, the hydraulic pump 61 operates, and the oil in the tank 71 is discharged to the pipe 59 via the filter 69 and the pipe 67. The oil discharged to the pipe 59 is sent to the servo valve 57 by the operation of the accumulator 65, and the valve of the servo valve 57 is controlled based on a preset machining pattern by an NC device (not shown) to move the oil passage 53. Then, it is sent to the upper cylinder chamber 49 of the hydraulic cylinder 37.

The oil sent into the upper cylinder chamber 49 of the hydraulic cylinder 37 causes the ram 43 to descend via the piston 39. When the ram 43 descends, the striker 47 descends to press and lower the punch 17, whereby the punch 17 and the die 19 cooperate with each other to perform desired press working on the work W.

After the desired press work is applied to the work W, the piston
When 39 rises, a large amount of oil is returned from the lower cylinder chamber 51 to the tank 71 through the oil passage 75 and the pipe 77.

At this time, since a large amount of oil flows in a short time, a large pressure is generated and a metallic sound such as a water hammer is generated, but at this time, by putting a part of the return oil into the cylinder type accumulator 81, this metal It can almost completely eliminate the target sound.

As a concrete configuration of the cylinder type accumulator 81, as shown in FIG. 2, a vertically movable piston 85 is mounted in a cylinder body 83. Further, the upper cover 87 and the lower cover 89 are provided on the upper and lower parts of the cylinder body 83.
Is provided. A plurality of springs 91 and 93 are interposed between the piston 85 and the lower cover 89 so as to urge them upward.

An oil passage 95 is formed in the upper cover 87 and an oil passage 97 is formed in the lower cover 89, and the oil passage 95 is connected to the pipe 79. The oil passage 97 is open to the atmosphere. With the above configuration, a part of the return oil is put into the cylinder type accumulator 81. That is, high-pressure oil, which is a part of the return oil, enters the cylinder chamber through the oil passage 95 and pushes the piston 85, is relaxed by the biasing force of the springs 91 and 93, and is discharged from the cylinder chamber through the oil passage 95. The oil pressure will decrease.

Next, when the return oil of the second wave comes in, it collides with the return oil of the first wave and a pressure lower than the atmospheric pressure appears. However, since the oil passage 97 formed in the lower cover 89 is released to the atmospheric pressure, the oil breathes here to alleviate the pulsating flow and the return oil is returned to the tank 71. As a result, the metallic sound of the water hammer can be removed almost completely. Also, since the life of the piston 85 and the springs 91, 93 is semi-permanent,
The cylinder type accumulator 81 can be used semipermanently to reduce the cost.

FIG. 3 shows another embodiment of the cylinder type accumulator 81. In FIG. 3, the same parts as those in FIG. 2 are designated by the same reference numerals, and only different points will be described. Spring 91A, 93A;
The piston 85 is in a floating state with B and 93B interposed. This will have the effect of eliminating the negative pressure of the return oil, and it will be possible to further remove the water hammer.

The present invention is not limited to the above-described embodiments, but can be implemented in other modes by making appropriate changes.

[Effect of the Invention] As can be understood from the above description of the embodiment, according to the present invention, the upper die and the lower die cooperate with each other by pressing the ram up and down by the hydraulic cylinder to press the work. Is performed. When the ram descends by the hydraulic cylinder and punches up the work, it then rises, and a large amount of oil flows out from the cylinder chamber to the tank in a short time, causing a large pressure and a metallic hammer noise. To do.

At this time, if a part of the drained oil is put into the cylinder type accumulator provided in the return circuit of the hydraulic circuit in the hydraulic cylinder, the pressure will be reduced in the cylinder type accumulator, and it will flow gradually from the cylinder type accumulator to the tank, not in a lump form. As a result, the noise due to the collision of oil spills can be eliminated, and the metallic sound of the phenomenon called water hammer can be almost completely removed, and the life of the cylinder type accumulator is semi-permanent and it can be used to reduce the cost. You can

[Brief description of drawings]

FIG. 1 shows a main part of the present invention, and an enlarged detailed view of an arrow I portion in FIG. 4, FIG. 2 is an enlarged sectional view of an arrow II portion in FIG. 1, and FIG. Alternative Embodiment Figure, 4th
The drawing is a side view of a hydraulic punch press according to an embodiment of the present invention. 1 …… hydraulic punch press machine (hydraulic press machine), 17 ……
Punch (upper mold), 19 ... Die (lower mold), 21 ... Cylinder mounting, 37 ... Hydraulic cylinder, 39 ... Piston, 43 ... Ram, 51 ... Lower cylinder chamber, 71 ... Tank, 75 ...... Oil passage, 77, 79 ...... Piping, 81 ...... Cylinder type accumulator

Claims (1)

[Scope of utility model registration request] 1. An upper die (17) for moving a ram (43) up and down via a piston (39) by the operation of a hydraulic cylinder (37).
A hydraulic press machine for pressing a work (W) in cooperation with a lower die (19), wherein a cylinder chamber 7 of a hydraulic circuit in the hydraulic cylinder (37) and a tank (71) are connected. A cylinder type accumulator (81) is provided in the middle of the return circuit (75, 77, 79), and when the piston (39) is raised, the drain oil in the cylinder chamber is put into the cylinder type accumulator (81) once. Decrease the pressure of drain oil, and move from the cylinder type accumulator (81) to the tank (7
A hydraulic press machine characterized in that the cylinder type accumulator (81) is configured so that drained oil gradually flows up to 1).