JPH057561B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic pressure generator for a hydraulic press, and more particularly to a hydraulic pressure generator for reversibly generating high-pressure, large-capacity hydraulic pressure at high speed to operate a hydraulic press at high speed.

Press machines can be classified according to the type of drive source: mechanical presses, such as screw presses, and hydraulic presses, which use hydraulic cylinders. In general, mechanical presses are more suitable for high-speed operation, especially those that store work energy in the form of rotational energy in a flywheel and extract it at any time using a clutch and brake mechanism. The quality is also good. However, if a large slide adjustment is required for the slide screwed onto the screw spindle, the structure becomes complicated, and especially in a casting press that requires high pressure relative to its size, it can be reduced to a realistic size. This is a difficult point to raise.

On the other hand, hydraulic presses are superior in that they can provide a relatively large pressing force, but there are various problems in obtaining the hydraulic pressure that serves as the driving source.

In conventional hydraulic presses, there are two methods: one that relies on the horsepower of a hydraulic pump to generate all of its work energy, and the other that temporarily stores potential energy in an accumulator and releases it all at once during work.

In the former case, the pump has pressure or discharge limitations, and the oil pressure cannot be increased too high, making it difficult to increase the speed. Therefore, if you try to increase the speed, you will be forced to waste an unrealistically large amount of energy. In addition, a cylinder with a large diameter is required to achieve high pressure, and it is difficult to realistically reduce the size of the cylinder.

On the other hand, the latter type of accumulator press requires a complicated control system, and in addition, the accumulator requires a large installation space and frequent maintenance and inspection.

Additionally, hydraulic presses generally require a control valve to be provided in the main circuit, which creates a large resistance to the flow of hydraulic pressure and causes a large pressure loss.

Furthermore, these valves cannot withstand use under high pressure, which is a major obstacle to increasing the pressure of hydraulic presses.

SUMMARY OF THE INVENTION An object of the present invention is to provide a high-pressure, high-speed, energy-saving hydraulic pressure generator with little noise.

Furthermore, the present invention eliminates the above-mentioned drawbacks and problems regarding the hydraulic power source of conventional hydraulic presses, eliminates the need to provide a valve in the main circuit, and allows hydraulic presses to operate at high speeds comparable to or even higher than mechanical presses, and with high loads. It is an object of the present invention to provide a hydraulic pressure generating device for driving a hydraulic press that can be operated under pressure.

Further, it is an object of the present invention to provide a hydraulic generating device (pump) for driving various hydraulic devices that is easy to control, can be assembled compactly as a whole, and is easy to maintain.

The hydraulic pressure generating device according to the present invention penetrates the respective rotating shafts of a pair of outer gears that are rotated in opposite directions by a flywheel, and selectively connects the outer gears and the rotating shafts via a clutch to form a gear train. a drive unit that rotates the screw spindle in forward and reverse directions; and a drive unit that rotates the screw spindle in the forward and reverse directions; The hydraulic oil in the cylinders, into which the plungers on both sides of the slide member enter and exit, is alternately pumped and reversed to and from the closed circuit hydraulic system connected to the respective cylinders. has been done.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a hydraulic pressure generator for driving a high-speed hydraulic press according to an embodiment of the present invention.

The hydraulic pressure generating device of this embodiment is composed of a hydraulic pressure generating section and its driving section.

First, the hydraulic pressure generating section will be explained.

A hydraulic pressure generating unit housing is constituted by fixed frames 15, 16, and 17 that are fastened in the axial direction with tie boilers, and a screw spindle 14 is pivotally supported on the frame 15 at the end of the driving unit via a bush 21. ing.

The screw spindle 14 is provided with a threaded portion extending into the housing, and a slide 20 that moves within the frame is screwed into the threaded portion.

Annular plungers 18 and 19 are fixed to both end surfaces of the slide 20, and the plungers 18 and 19 are fixed to the frames 15 and 17 at both ends, respectively.
Annular cylinder chambers 22 and 23 into which 19 is slidably fitted
A hydraulic suction port or discharge port 24, 25 communicating with the cylinder chamber is formed.

The slide 20 is guided by an intermediate annular frame 16 that forms the housing, and moves left and right within the housing by rotation of the screw spindle 14, and the plungers 18 and 19 move in their respective cylinder chambers 22 and 23 accordingly. Slide inside. By sliding these plungers 18 and 19, the liquid (hydraulic pressure) for driving a hydraulic press (not shown) is passed through the suction port or the discharge port 24 or 25 into the cylinder chamber 22.
Or, the oil is sucked out from inside 23 and the return oil is in the cylinder chamber 2.
Inhaled within 3 or 22 hours.

Note that the present invention is not limited to the embodiment in which the plungers 18, 19 and the cylinder chambers 22, 23 are formed in an annular shape and provided one each on the frames 15, 17 at both ends, but a plurality of plungers are provided at both ends. A plunger and a cylinder chamber may be provided. In this case, the plunger is formed into a solid rod shape, and the cylinder chambers are correspondingly formed into a plurality of independent hollow chambers.

Next, the driving section of this embodiment will be explained with reference to FIG. 2 as well.

A main gear 9 is fixed to the protruding end of the screw spindle 14. A pair of pinions 8 and 10 are meshed with this main gear 9. Pinion shafts (rotating shafts) 7, 12 of each pinion 8, 10
are pivotally supported by the press body via rolling bearings 26, 27 and 28, 29. The rotating shafts 7 and 12 are inserted into outer ring gears 30 and 31 that are always in external engagement with each other and rotate in opposite directions.
Between the rotating shafts 7, 12 and the outer gears 30, 31, there are clutch plates attached to the outer circumferential surfaces of the rotating shafts 7, 12 and clutch plates attached to the inner circumferential surfaces of the outer gears 30, 31. Multi-plate hydraulic clutches 6, 11 are provided.

Therefore, when the multi-disc hydraulic clutch is in the "on" state, the outer gear and rotating shaft rotate together, causing the "off" state.
In this state, only the outer gear rotates and the rotating shaft is free. Further, one of the outer gears 30 (or 31) meshes with a pinion 5 mounted on a flywheel shaft 4 that is pivotally supported by the press body.

This flywheel shaft 4 has a flywheel 3
A belt pulley 2 is attached, and is continuously driven to rotate in one direction via the belt 1 by a motor (not shown). On the other hand, the rotating shaft 12 or 7 penetrates into the other 31 or 30 of the outer ring gear.
A brake mechanism 13 is attached to the shaft end.

In such a configuration, the flywheel 3 is always rotated in one direction by the motor and retains kinetic energy due to rotation.

At the same time, the outer gears 30 and 31 are constantly rotating in opposite directions via the flywheel shaft 4 and the pinion 5 attached to the shaft.

Here, suppose that the outer gear 30 is viewed from the front in the figure.
It is assumed that the rotation direction of the outer ring gear 31 is clockwise and that the outer ring gear 31 is counterclockwise. In this state, one of the clutches 6
When set to "on", the rotating shaft 7 and pinion 8
rotates clockwise, and main gear 9 rotates counterclockwise. This is the screw spindle 1
4 rotates counterclockwise, and in this rotating direction, the slide 20 moves, for example, to the right, and the cylinder chamber 23
Pressure oil is discharged from the cylinder through the discharge port 25, returns to the cylinder chamber 22, and is sucked in through the suction port 24. At this time, the other clutch 11 is in the "disengaged" state, and the rotating shaft 12 and pinion 10 are idle clockwise without being affected by the rotation of the outer gear 31.

Immediately before the slide 20 reaches the right-hand limit position, a signal is given to disengage one clutch 6 and a signal to engage the brake mechanism 13 of the other rotating shaft 12, whereby the pinion 10 transfers the brake torque to the main gear. 9 and pinion 8, these rotating shafts and the screw spindle 14 are stopped, and the slide 20 is also stopped.

As described above, the flywheel 3 and the outer gears 30, 31 of the clutches 6, 11 continue to rotate. When the other clutch 11 is turned on after the slide 20 has stopped, the screw spindle 14 rotates clockwise in the opposite relationship to that described above, and the slide 20 moves to the left, causing the cylinder chambers 22 and 23 to move out. The discharge and suction of hydraulic pressure is the opposite of the above.

As mentioned above, in the present invention, the rotary kinetic energy of the flywheel can be converted into the reciprocating movement of the slide and plunger without waste, so it is possible to generate high-pressure, high-speed, and large-volume hydraulic oil, which is useful for hydraulic presses that require high oil pressure. This is possible, and the hydraulic press can be operated at a high speed comparable to that of a mechanical press.

In addition, there is less noise that is typical of hydraulic presses, and since no control valve is required in the main circuit, there is less pressure loss and significant energy savings can be achieved. Furthermore, not having to use large pressure-limited valves provides significant maintenance benefits in addition to allowing higher pressures in the hydraulic press.

The hydraulic pressure generator of the present invention can be used not only for the above-mentioned hydraulic press but also for hydraulic actuators and other various hydraulic drive devices, and can be used in combination with a position sensor to provide switching signals to each clutch and brake mechanism. , it is possible to obtain a hydraulic pressure generating device that does not require a valve and has good controllability.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a hydraulic pressure generator for driving a hydraulic press according to an embodiment of the present invention, and FIG. 2 is a diagram schematically showing the arrangement of a gear train and a clutch in the embodiment of FIG. . 3... Flywheel, 5, 8, 10... Pinion, 6, 11... Multi-plate hydraulic clutch, 9...
Main gear, 13... Brake mechanism, 14... Screw use spindle, 15, 16, 17... Fixed frame, 18, 19... Plunger, 20...
Slides, 22, 23... cylinder chamber.

Claims (1)

[Claims] 1 A rotating shaft is inserted into each of a pair of outer ring gears that are rotated in opposite directions by a flywheel, and the outer ring gears and the rotating shaft are selectively connected via a clutch to rotate the screw spindle in the forward and reverse directions via a gear train. The plunger is fixed to both end surfaces of a slide member that is screwed into the screw spindle so that the plunger is reciprocated within the thin lid according to the forward and reverse rotation of the screw spindle. The hydraulic oil in the cylinder into which the plungers on both sides of the slide member move in and out is alternately pumped and reversed to a closed circuit hydraulic system connected to the cylinder. Hydraulic pressure generator for driving hydraulic presses.