JPH10128599A - In-line type hydraulic accumulator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simultaneously achieve large capacity accumulator function and a space saving by arranging a piston having an orifice hole in a pressure receiving face in a cylinder against a spring means energizing in the pressure receiving direction of a cylinder so as to enable a sliding displacement in the longitudinal direction. SOLUTION: This in-line type accumulator 8 for pulsation absorption is arranged with a piston 10 and a compression coil spring 11 in an in-line type and straight tubular slender cylinder container 9, further, an orifice hole 12 for passing a T line is pierced at the center part of the piston 10. Thus, it is very easy to accommodate/arrange the accumulator 8 in a press machine main body due to an in-line construction space-wise. Further, due to the fact the orifice hole 12 is arranged at the center part of the piston 10 of the accumulator 8, a throttle function as a passing hole of the T line is realized so as to have a function to appropriately absorb pulsation pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an accumulator for absorbing a hydraulic pulsation of, for example, a hydraulically driven sheet metal working machine, and more particularly to an in-line hydraulic accumulator.

[0002]

2. Description of the Related Art For example, a hydraulic tank line of a hydraulic circuit used in a conventional ram hydraulic driven sheet metal working machine such as a punching press absorbs a hydraulic pulsation such as a water hammer at the time of oil recirculation from a ram. FIG. 3 shows an example of a simplified diagram thereof. For example, a spring piston type accumulator as shown in Japanese Utility Model Publication No. Hei 7-15678, for example,
T (tank) of manifold of hydraulic cylinder for ram drive
It was arranged downward in the port section.

In FIG. 3, 1 is a hydraulic tank, 2 is a hydraulic cylinder for driving a ram of a punch press, 3 is its piston, 4 is a servo valve, 5 is a manifold, 6 is its T (tank) port, 7 is 3 shows a flexible rubber hose.

At the outlet of the T port 6 of the manifold 5,
A pulsation absorbing accumulator 8 </ b> A is provided between the rubber hose 7. The main body of the accumulator 8A is a normal cylindrical cylinder container 9A, in which a piston 10A and a compression coil spring 11A are provided.

[0005]

However, as the punching press of this kind becomes larger and more powerful, the flow rate of the drain which is rapidly recirculated to the tank line when the piston 3 rises is increased. The capacity and size of the accumulator 8A are also increased, making it difficult to accommodate the accumulator 8A in the frame of the punch press machine body.

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and by using a conventional cylindrical accumulator with an in-line configuration, it is possible to simultaneously increase the capacity of this type of accumulator function and save space. It is intended to provide means that can be realized and housed in a press machine frame.

[0007]

Therefore, in the present invention, a part of the circulation circuit from the hydraulic press forms a relatively long cylinder vessel in the form of a straight pipe, and an orifice is formed in the cylinder in the pressure receiving surface. A piston with a hole,
Against spring means for urging in the pressure receiving direction of the cylinder,
By providing an in-line hydraulic accumulator characterized by being slidably displaceable in the longitudinal direction,
It is intended to achieve the above object.

[0008]

According to the structure of the present invention described above, since the outer shape is inlined, the storage of the accumulator in the machine main body is advantageous in terms of space, and the orifice hole structure of the piston provides a sufficient pulsating pressure absorbing capacity. T with
The pressure resistance and the like of the flexible rubber hose reaching the hydraulic tank of the port line can be protected.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
This will be described in detail based on one embodiment.

[0010]

FIG. 1 is a schematic sectional view showing an embodiment of an in-line hydraulic accumulator according to the present invention. The same (corresponding) functional components as in FIG. 3 of the prior art are denoted by the same reference numerals or the same reference numerals without suffixes.

(Structure) In FIG. 1, 1 is a hydraulic tank,
2 is a hydraulic cylinder for ram operation of a punch press, 3 is its piston, 4 is a servo valve, 5 is a manifold,
6 is a T (tank) port, and 7 is a flexible rubber hose.

A feature of the embodiment of the present invention is that an accumulator 8 for absorbing pulsation is formed in an in-line type, and a piston 10 and a compression coil spring 11 are provided inside an elongated cylinder container 9 having a straight pipe shape. An orifice hole 12 for passing the T line is formed in the center of the.

(Operation) The accumulator 8 of the present embodiment comprises:
With the in-line configuration as described above, the conventional example shown in FIG.
Unlike the bulk-like outer shape shown in Fig. 7, it is extremely easy to space and house in the press machine body.

The provision of the orifice hole 11 in the center of the piston 10 of the accumulator 8 realizes the function of a throttle as a passage hole for the T line, and thereby the piston 3 of the ram cylinder 2 (FIG. 3). When the pressure rises, a sudden discharge pressure is applied to the pressure receiving surface of the accumulator piston 10, which strokes against the urging force of the spring 11, thereby functioning to appropriately absorb the pulsating pressure.

(Operation) The above operation will be described with reference to FIG. FIGS. 4A and 4B schematically show the stroke displacement of the piston 10 and the change in the amount of oil passing through the orifice hole 11 when the flow rate of the T line is relatively small and the flow rate is relatively large, respectively. FIG.

As shown in both figures, it is possible to avoid an excessive pressure applied to the flexible rubber hose 7 in accordance with the amount of the recirculated oil, thereby protecting the pressure resistance thereof.

[0017]

As described above, according to the present invention, the in-line accumulator can be disposed in the hydraulic circuit of a hydraulically driven sheet metal working machine or the like in a machine body in a space advantageous manner. Thus, a desired pulsation absorbing effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an external configuration of an in-line hydraulic accumulator according to one embodiment.

FIG. 2 is an operation explanatory diagram of the accumulator.

FIG. 3 is a schematic sectional view of an example of a conventional hydraulic accumulator for a punch press.

[Explanation of symbols]

 Reference Signs List 1 hydraulic tank 2 ram drive hydraulic cylinder 3 piston 4 servo valve 5 manifold 6 T (tank) port 7 rubber hose 8 in-line accumulator 8A cylindrical accumulator 9 pipe-shaped cylinder container 9A cylindrical cylinder container 10, 10A piston 11, 11A compression Coil spring 12 orifice hole

Claims (1)

[Claims] 1. A part of a circulation circuit from a ram of a hydraulic press forms a relatively long cylinder container having a straight pipe shape, and a piston having an orifice hole in a pressure receiving surface in the cylinder is provided. An in-line hydraulic accumulator characterized in that it is slidably displaceable in the longitudinal direction against spring means for urging in the direction.