JPH0727103A - Extra high pressure producing device - Google Patents

Abstract

PURPOSE:To provide a simple and inexpensive device by forming a hydraulic circuit in which one booster is driven into pre-pressurizing, pressurizing, and intake strokes by a hydraulic pump, and another booster is driven similarly by another hydraulic pump. CONSTITUTION:A booster 1 is driven by a hydralic pump 11 and a hydraulic cylinder 6a to perform the pre-pressurizing, pressurizing, and intake strokes, and a booster 2 is driven similarly by a hydraulic pump 12 and a hydraulic cylinder 6b. Rod-chamber side ports Pr of the boosters 1, 2 are then connected to each other by means of a line 23 provided with a back pressure setting check valve 24 to supply the pressure oil discharged from the advancing side booster to the returning side booster to accelerate the returning action. Thus, even when an accumulater is not provided on the delivery lines 15, 16 of the hydraulic pumps, load fluctuations in the hydraulic pumps 11, 12 can be reduced. As a result, the displacements of the hydraulic pumps can be reduced, manufacturing cost can be reduced, and the device can be miniaturized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrahigh pressure generator having a booster for pressurizing water sucked into a plunger chamber to an ultrahigh pressure by reciprocating a hydraulic cylinder.

[0002]

2. Description of the Related Art Conventionally, as an ultrahigh pressure generator of this type,
For example, the one shown in FIG. 5 is known. This ultrahigh pressure generator pressurizes the water sucked from the water supply line 7 into the plunger chambers 3a and 3b through the check valves 4a and 4b by the reciprocating movement of the hydraulic cylinders 6a and 6b, and then through the check valves 5a and 5b. It has a first booster 1 and a second booster 2 for discharging to the discharge line 8, and three switching positions of pressurization, pre-pressurization, and suction, and the first load port A has a hydraulic cylinder 6a,
First and second switching valves 9 and 10, which are respectively connected to the head chamber side port Ph of 6b and whose outlet port R is connected to the return line 20 leading to the tank 32, a check valve 54 and an accumulator 55 are provided. The discharged discharge line 53 is connected to the pressure ports P of both the switching valves 9 and 10, and a hydraulic pump 51 for pressurizing the pistons of both hydraulic cylinders is moved forward, and a discharge line 56 provided with a check valve 57. , Line 5
To the rod chamber side port Pr of both hydraulic cylinders 6a, 6b via 8 and a suction hydraulic pump 52 for returning the pistons of both hydraulic cylinders, and a line 59 connecting the line 58 and the return line 20. The water discharge line 8 including the relief valve 60 interposed and the opening / closing valve 33 interposed
From the jet nozzle 34 installed at the tip of the super high pressure water (3000kgf
/ Cm ² ) is sprayed to cut the material 35 to be cut. A cooler 21 and a filter 22 are sequentially provided on the return line 20.

[0003]

In the above-mentioned conventional ultrahigh pressure generator, the first switching valve 9 is at the left side (pressurization) position in the drawing, and the piston of the hydraulic cylinder 6a of the first booster 1 is
When the piston moves forward at high speed by the pressure oil supplied from the pressurizing hydraulic pump 51 to the port Ph on the head chamber side, the return end sensor 6 is reached before the piston reaches the forward end sensor 62a.
The second switching valve 10 is switched from the right side (suction) position to the neutral (pre-pressurization) position by the detection signal of 3b, and the second booster 2
However, it changes from the suction stroke to the pre-pressurization stroke, which moves at a low speed.
Then, at the time when the first booster 1 reaches the forward end sensor 62a and finishes the discharge of the ultra-high pressure water to the water discharge line 8, the second booster 2 having advanced the pre-pressurization process is the forward end sensor 62a. When the second booster 2 is in the pressurizing stroke, it switches from the neutral position to the left (pressurizing) position by the detection signal of and discharges the ultra-high pressure water to the water discharge line 8. The first booster 1 is designed to perform the same pre-pressurization stroke, and even if the water discharge line 8 does not have an accumulator, it is possible to reduce fluctuations in the water pressure of the ultrahigh pressure water.

However, in such a structure, it is necessary to supply pressure oil from the pressurizing hydraulic pump 51 to both one booster in the pressurizing stroke and the other booster in the prepressurizing stroke. There is no choice but to increase the capacity of the hydraulic pump 51. Further, the load of the hydraulic pump 51 greatly changes between the strokes of one-side pressurization and the other side pre-pressurization and the strokes of the one-side pressurization and the other side suction, and the stroke of the pre-pressurization is lengthened in order to suppress this change. It is necessary to provide an accumulator 55 for hydraulic pressure in the discharge line 53. Therefore, there are problems that the hydraulic pump and the booster are increased in size and the manufacturing cost is increased. Further, when the first and second boosters 1 and 2 approach the stroke end, the suction hydraulic pump 52.
The pressure of the line 58 is increased by the pressure oil supplied from
Due to this pressure increase, the relief valve 60 of the line 59 is opened, and excessive pressure oil is discharged to the tank 32, which causes a problem of energy loss.

Therefore, an object of the present invention is to drive one booster with one hydraulic pump in pre-pressurization, pressurization and suction strokes,
By devising the hydraulic circuit so that the other pump similarly drives the other booster, there is no need for a hydraulic accumulator, the hydraulic pump can have a small capacity, energy loss can be eliminated, and the water discharge line It is an object of the present invention to provide a simple and inexpensive ultrahigh pressure generator capable of omitting the high pressure accumulator.

[0006]

In order to achieve the above object, an ultrahigh pressure generator according to the present invention comprises hydraulic cylinders 6a and 6b.
The first booster 1 and the second booster 2 that pressurize the water sucked into the water pressurizing plunger chambers 3a and 3b and discharge the water to the water discharge line 8 by the reciprocating movement of the first hydraulic pump 11
And the second hydraulic pump 12, the pressure ports P connected to the discharge lines 15 and 16 of the first and second hydraulic pumps 11 and 12, and the heads of the first and second hydraulic cylinders 6a and 6b. Each first load port A connected to the room side port Ph
And the respective outlet ports R connected to the return line 20 leading to the tank 32, and having the three switching positions of pressurization, pre-pressurization and suction, the first switching valve 9 and the second switching valve 1
0, and a line 2 connecting the rod chamber side port Pr of the first and second hydraulic cylinders 6a, 6b and the return line 20.
3 and the check valve 24 for setting back pressure, the hydraulic cylinder side of the check valve 24 for setting back pressure in the line 23, and the second load ports of the first and second switching valves 9 and 10. The lines 25 and 26 connecting B are provided with check valves 27 and 28, respectively, which are interposed so as to prevent the flow toward the first and second switching valves 9 and 10, respectively. To do.

[0007]

In the ultrahigh pressure generator according to the present invention, it is assumed that the first switching valve 9 is switched to the pressurizing switching position and the second switching valve 10 is switched to the suction switching position. Then, from the first hydraulic pump 11 through the first switching valve 9, the first booster 1
While the pressure oil is supplied to the head chamber side port Pr of the second
Pressure oil is supplied from the hydraulic pump 12 to the rod chamber side port Pr of the second booster 2 via the line 23 having the second switching valve 10 and the check valve 28 interposed therebetween.
It is discharged from the port Pr on the rod chamber side of the booster 1 and merges with the pressure oil whose flow to the tank 32 is regulated by the check valve 24 for setting the back pressure. Therefore, the first booster 1 moves forward and discharges the high-pressure pressurized water from the plunger chamber 3a to the water discharge line 8, while the second booster 2 returns to the plunger chamber 3b at high speed by the combined pressure oil. Inhale. When the second booster 2 reaches the backward movement end, the second switching valve 10 is switched to the pre-pressurization switching position, so that the first booster 1 reaches the forward movement end and ends the water discharge. The second booster 2 that has undergone the pressurization process is in a state capable of discharging high-pressure pressurized water from the plunger chamber 3b. And the first
When the booster 1 reaches the forward end, the first switching valve 9 is switched to the switching position from pressurization to the suction, and the second switching valve 10 is switched to the switching position from pre-pressurization to pressurization. Therefore, the first booster 1 starts returning and changes to the suction stroke, and the second booster 2 changes to the high-speed pressurization stroke to change the water discharge line 8
Fluctuations in the water pressure of the ultra-high pressure water discharged to are significantly reduced even without a high pressure accumulator.

The second booster 2 in the pressurization stroke discharges high-pressure pressurized water from the plunger chamber 3b to the water discharge line 8, while the first booster 1 in the suction stroke sucks water into the plunger chamber 3a. At this time, similarly to the above, the second
The pressure oil discharged from the rod chamber side port Pr of the booster 2 and regulated in flow to the tank 32 by the back pressure setting check valve 24 is supplied from the first hydraulic pump 11 to the rod chamber side port Pr of the first booster 1. It joins the pressure oil supplied to. Therefore, the first booster 1 returns to the high speed by the combined pressure oil and sucks water into the plunger chamber 3a. Then, when the first booster 1 reaches the return end, the first switching valve 9 is switched to the pre-pressurization switching position. As a result, when the second booster 2 reaches the forward end and finishes water discharge, the second booster 2 having advanced the pre-pressurization stroke is in a state capable of discharging high-pressure pressurized water from the plunger chamber 3b. . Then, when the second booster 2 reaches the forward end, the second switching valve 10 is switched from the pressurization to the suction switching position, and the first switching valve 9 is switched from the pre-pressurization to the pressurization switching position. Therefore, the second booster 2 starts moving back and changes to the suction stroke, and the first booster 1 changes to the high-speed pressurization stroke, and the water pressure fluctuation of the ultra-high pressure water discharged to the water discharge line 8 changes to the high pressure accumulator. Even without it, it is significantly reduced.

As described above, the first hydraulic pump 11 and the first hydraulic cylinder 6a drive the first booster 1 so as to perform the prepressurizing, pressurizing, and suction strokes, and the second hydraulic pump 12 and the second hydraulic pump 12a. The second booster 2 is similarly driven by the cylinder 6b, and the rod chamber side ports Pr of both boosters 1 and 2 are driven.
Are connected to each other through a line 23 having a check valve 24 for setting back pressure, and the pressure oil discharged from the booster on the forward movement side is supplied to the booster on the backward movement side to accelerate the backward movement. The load fluctuations of the hydraulic pumps 11 and 12 can be reduced without providing accumulators in the discharge lines 15 and 16 of the hydraulic pumps, and a large amount of excess pressure oil is not discharged to the tank through a relief valve as in the conventional case. Therefore, energy loss can be reduced.

[0010]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 is a circuit diagram showing an ultrahigh voltage generator of the present invention. In this ultrahigh pressure generator, a first booster 1 and a second booster 2 are connected to an ultrahigh pressure water discharge line 8 in parallel with each other via discharge check valves 5a and 5b. , The water sucked from the water supply line 7 into the plunger chambers 3a, 3b for water pressurization through the suction check valves 4a, 4b by the reciprocating motions of the hydraulic cylinders 6a, 6b, respectively, to an ultrahigh pressure, and the water discharge line 8 To discharge. First above
Between the booster 1 and the variable displacement type first hydraulic pump 11, and between the second booster 2 and the variable displacement type second hydraulic pump 12, the hydraulic cylinders 6a and 6b are pressurized so as to reciprocate,
First and second switching valves 9, 10 having switching positions for pre-pressurization and suction
And each of the hydraulic pumps 11 and 12 and the tank 32 constitute a hydraulic power source.

That is, the first switching valve 9 includes a pressure port P, an outlet port R, a first load port A, and a second load port B.
Each port of PA, PA,
RB connection, PB, RA connection at right position, ie suction position,
In the neutral position, that is, in the pre-pressurization position, the PAs are connected by a passage having a throttle 13, and the RBs are closed. The second switching valve 10 also has the same structure as the above-described first switching valve 9 except that the PAs are connected by a passage having a throttle 14 at the neutral position. The pressure port P of each switching valve 9, 10 is connected to the corresponding hydraulic pump via the discharge lines 15, 16 having the check valve 19, and the first load port A is connected via the line 17, 18 for the corresponding hydraulic cylinder 6a, 6b. And the outlet port R is connected to the head chamber side port Ph of the common return line 20 with the cooler 21 and the filter 22 interposed therebetween.
Connected to. The rod chamber side port Pr of each hydraulic cylinder 6a, 6b is connected to the return line 20 by a common line 23 provided with a check valve 24 for setting a back pressure that regulates the flow to the tank 32. Further, on the hydraulic cylinder side from the check valve 24 of the common line 23,
Connected to the second load port B of each switching valve 9, 10 by a line 25, 26 in which check valves 27, 28 are provided so as to block the flow toward the first and second switching valves 9, 10. There is.

On the other hand, the first hydraulic cylinder 6a of the above embodiment.
Includes a first forward movement sensor 29 including a magnet type reed switch for detecting that the piston in the forward stroke, that is, the pressure stroke, has reached the vicinity of the end of the pressure stroke, and the piston in the backward stroke, that is, the suction stroke, A similar first return sensor 29 'is provided to detect that the proximity has been reached. Further, the second hydraulic cylinder 6b is also provided with the same second forward movement sensor 30 and second return movement sensor 30 '. The relationship between the mounting positions of the above-described sensors is a graph in which the vertical axis represents a stroke with the suction stroke (return) end set to zero, and the horizontal axis represents time, showing the change over time in the stroke of each hydraulic cylinder 6a, 6b. 3 is explained as follows. That is, when the first hydraulic cylinder 6a indicated by the solid line descending to the right in FIG. 3 reaches the first return sensor 29 ', the first switching valve 9 is moved from the right position to the neutral position and pressure is applied to the first hydraulic cylinder 6a. When the oil is supplied, the second hydraulic cylinder 6 shown by the broken line rising to the right in FIG.
Before b reaches the second forward movement sensor 30 at the end of the pressure stroke,
The pressure stroke of the first hydraulic cylinder 6a is increased up to the compression volume of water as shown by the solid line rising to the right in the figure, for example, 300
In the case of pressurization of 0 kg / cm ² , the process proceeds up to 9% of the entire stroke, and the water pressure in the plunger chamber 3 a of the first booster 1 becomes a predetermined ultrahigh discharge pressure. On the contrary, it is clear from FIG. 3 that the same can be said while the second hydraulic cylinder 6b reaches the second backward movement sensor 30 ′, switches to the pressurization stroke, and reaches the second forward movement sensor 30. is there.

Further, as shown in FIG. 1, in the ultrahigh pressure generator of the above-mentioned embodiment, each of the sensors 29, 29 ', 30,
In response to the detection signal from 30 ', the first and second switching valves 9,1
A control unit 31 is provided as a control unit for switching control of 0. When the first switching valve 9 is located at the left side position in the drawing and the first booster 1 is in the pressurizing stroke, the control unit 31 receives the detection signal of the second backward movement sensor 30 'and receives the second switching valve. 1
0 is switched from the right side position to the neutral position, and then the first switching valve 9 is moved from the left side position to the right side position and the second switching valve 10 is moved from the neutral position to the left side position in response to the detection signal of the first forward movement sensor 29. Switch. Further, when the second switching valve 10 is located at the left side position in the drawing and the second booster 2 is in the pressurizing stroke, the first switching valve 9 is moved to the right side position in response to the detection signal of the first backward movement sensor 29 '. To the neutral position, then the second
In response to the detection signal of the forward movement sensor 30, the second three-position switching valve 10 is switched from the left side position to the right side position, and the first three-position switching valve 9 is switched from the neutral position to the left side position.

More specifically, by the control unit 31,
The switching valves 9 and 10 are controlled as follows. That is, FIG.
At time t ₁ , the first switching valve 9, which has been in the neutral position in FIG. 1 until then, is switched to the left position by the detection signal of the second forward movement sensor 30, and when the discharge pressure is, for example, 3000 kgf / cm ² , The first booster 1, which had advanced to 9% of the total pressurization stroke at a low speed until then, enters the high-speed pressurization stroke (see the solid line in FIG. 3), while the second switching valve that was at the left side position in FIG. 1 until then. 1
0 is switched to the right side position by the detection signal of the second forward movement sensor 30, and the second booster 2 moves from the pressurization stroke to the suction stroke.
(See the broken line in FIG. 3) (see FIG. 2 (A)). Next, at time t ₂ in FIG. 3, when the second return sensor 30 ′ detects the approach of the piston, the second switching valve 10 is switched to the neutral position in FIG. 1 and the second stroke which has reached the end of the suction stroke. Booster 2
Enters the low-speed pressurization stroke by refueling through the throttle 14 (Fig. 2
(See (B)). Further, at time t ₃ in FIG. 3, when the first booster 1 reaches the end of the pressurizing stroke and the first switching valve 9 is switched to the right position in FIG. 1 by the detection signal of the first forward movement sensor 29, The 2nd, which proceeded at a low speed up to 9% of the pressure stroke
In the booster 2, the second switching valve 10 is switched to the left side position by the detection signal of the first forward movement sensor 29,
The high-speed pressure stroke is entered (see FIG. 2 (C)). In addition,
The first and second boosters 1 and 2 are the throttles 13 of the switching valves 9 and 10,
14 to pressurize to the compression volume of water, eg 3000kg
In case of pressurization of / cm ² , the water pressure in the plunger chamber 3 becomes the discharge pressure of the specified ultra high pressure (eg 3000kgf / cm ² ) when the speed has reached to 9% of the total pressurization stroke at low speed. It has become.

As shown in FIG. 1, the ultrahigh pressure generator of the present invention has a water discharge line 8 connected to the first and second boosters 1 and 2, and an opening / closing valve 33 and a jet nozzle 34 toward the tip.
Are sequentially provided, and the material 35 to be cut is cut by the ultrahigh pressure water jetted from the jet nozzle 34.

The operation of the ultrahigh pressure generator having the above-mentioned structure is shown in FIG.
Will be described next with reference to. First, before the piston of the second booster 2 reaches the end of the pressurizing stroke shown in FIG. 2 (A), when the piston of the first booster 1 passes the first backward movement sensor 29 ', the sensor 29' The control unit 31 which has received the passage detection signal of the above switches the first switching valve 9 from the right side position to the neutral position, whereby the first booster 1 enters the low speed pressurization process by the throttle 13 from the suction process, and FIG. As shown in (A), when the second booster 2 reaches the end of the pressurizing stroke, the discharge pressure of the first booster 1 is, for example, 3000 kgf / cm ²
In the case of, the state is such that the pressurized water having the above-mentioned discharge pressure is discharged from the plunger chamber 3a by advancing by 9% of the entire pressurizing stroke. That is, when the second booster 2 finishes discharging the ultra-high pressure pressurized water, the ultra-high pressure pressurized water is discharged from the first booster 1, so that the high-pressure accumulator 61 (see FIG. 5) changes the water pressure in the water discharge line 8. Even if it is not provided, it is reduced, and ultra high pressure water without pulsation is jetted from the jet nozzle 34 at the tip (see FIG. 1) to the material 35 to be cut. And the second
The control unit 31 that receives the detection signal of the forward movement sensor 30 moves to the second
The switching valve 10 is switched from the left position to the right position, and the first switching valve 9 is switched from the neutral position to the left position. Thus,
The second booster 2 changes to the suction stroke, and the first booster 1
Turns into a fast pressurization stroke.

Next, as shown in FIG. 2B, when the second booster 2 reaches the second return sensor 30 'near the suction stroke end under the pressure stroke of the first booster 1, this sensor The control unit 31 that has received the passage detection signal from the 30 ′ has the second switching valve 1
0 is switched from the right side position to the neutral position, and the second booster 2
Starts a low-speed pressurization stroke by the throttle 14. Then, as shown in FIG. 2 (C), when the first booster 1 reaches the end of the pressurizing stroke, the second booster 2 has a discharge pressure of, for example,
In the case of 3000 kgf / cm ² , 9% of the total pressurizing stroke has progressed, and the pressurized water having the above-mentioned discharge pressure is discharged from the plunger chamber 3b. That is, at the time when the first booster 1 finishes discharging the ultra-high pressure pressurized water, the ultra-high pressure pressurized water is discharged from the second booster 2, so that the water pressure fluctuation in the water discharge line 8 is also reduced, and the jet nozzle 34 discharges the water. Ultra-high pressure water without pulsation is jetted. Then, the first forward movement sensor 29
The control unit 31 which has received the detection signal switches the first switching valve 9 from the left position to the right position and the second switching valve 10 from the neutral position to the left position. Thus, the first booster 1
Changes to the suction stroke, and the second booster 2 changes to the high-speed pressure stroke. As described above, even if an expensive ultrahigh pressure accumulator 61 (see FIG. 5) is not provided in the water discharge line 8, the water pressure fluctuation of the ultrahigh pressure pressurized water is reduced and the ultrahigh pressure water without pulsation is discharged from the jet nozzle 34. Since it can be injected into the cutting material 35, the performance and life of equipment such as boosters 1 and 2 used in hydraulic and hydraulic circuits can be improved, and the manufacturing cost and size of the ultra-high pressure control device and by extension the water jet cutting device can be reduced. Can be planned.

Since the throttles 13 and 14 are provided in the PA connecting passages in the neutral position, which is the pre-pressurizing switching position of the switching valves 9 and 10, the hydraulic pumps 11 and 12 are connected to the boosters 1 and 2, respectively. There is an advantage that the flow rate of the pressure oil supplied can be adjusted, the hydraulic pressure of the pressurized water in each of the plunger chambers 3a and 3b can be set to a predetermined discharge pressure with a short pre-pressurization stroke, and the cylinder can be downsized. In addition, the hydraulic cylinder 6 of each booster 1 and 2
The rod chamber side ports Pr of a and 6b are connected to the tank 32 by a common line 23 in which a check valve 24 for setting back pressure is provided.
To the return line 20 connected to the line 23, and to the lines 25 and 26 connecting the hydraulic cylinder side of the check valve 24 of the line 23 and the second load port B of the switching valves 9 and 10 to prevent the flow toward the switching valve. Check valves 27 and 2 respectively
8, the pressure oil discharged from the booster on the pressurizing stroke side is irrespective of the switching positions of the switching valves 9 and 10.
Since the flow to the tank 32 is regulated and flows into the booster on the suction stroke side to accelerate the suction stroke, that is, the backward movement of the piston, there is an advantage that the cycle time can be shortened.

Further, the first hydraulic pump 11 and the first hydraulic cylinder 6a drive the first booster 1 so as to perform the steps of pre-pressurization, pressurization and suction, and the second hydraulic pump 12 and the second hydraulic pump 12
Since the second booster 2 is similarly driven by the hydraulic cylinder 6b, in combination with the above-described acceleration of the backward movement by the supply of the pressure oil discharged from the forward side to the backward side, the pump discharge line 15, Even if the accumulator 55 (see FIG. 5) is not provided in 16, the load fluctuations of the hydraulic pumps 11 and 12 can be reduced, and excessive pressure oil is supplied to the tank through the relief valve 60 (see FIG. 5) as in the conventional case. The energy loss can be reduced because it is not released into the air. Further, the load fluctuation of the first and second boosters 1 and 2 can be reduced as compared with the case of refueling with a single and common hydraulic pump, and therefore, the water pressure of the super high pressure water discharged to the water discharge line 8 can be reduced. There is also an advantage that fluctuations can be reduced.

In the above embodiment, each hydraulic cylinder 6a, 6b is
Forward / backward movement sensors 29, 29 ', 30, 30' are provided on the both sides, and the control unit 31 alternately switches the first and second switching valves 9 and 10 on the basis of the detection signals of these sensors, so that both boosters are provided. Since the phase difference between 1 and 2 is controlled automatically,
There is an advantage that ultra-high pressure water without pulsation can be reliably obtained without providing an expensive high pressure accumulator in the water discharge line 8. In the above embodiment, the forward and backward movement sensors 29, 29 ', 30, 30' and their detection signals are used to control the phase difference between the boosters 1 and 2 via the first and second switching valves 9 and 10. Although the control unit 31 is provided, the control unit may be omitted.

FIG. 4 shows the hydraulic cylinder 6 of the first booster 1.
It is a side view showing an example of a forward and backward movement sensor provided in a. The first booster 1 includes head covers 37a and 37b that close both ends of the cylinder tube 36 and four tie bolts 38.
And a nut 39, and a piston 40 is fitted inside the hydraulic cylinder 6a, and a rod 41 continuing from the tip side of the piston 40 is fitted inside the plunger chamber 3a, and is connected to the tip side of the hydraulic cylinder 6a. Plunger tube 41
Consists of. Head covers 37a, 37b of the hydraulic cylinder 6a
Are head chamber side port Ph and rod chamber side port Pr respectively.
Is provided, and the head cover 4 of the plunger tube 41 is provided.
2 is provided with check valves 4a and 5a for suction and discharge. Cylinder tube 36 and head cover 37a, 37
The b is made of a non-magnetic material such as 18-8 stainless steel, while the piston 40 is made of a magnetic material such as steel. On the other hand, the sensor 29 is composed of a magnet type reed switch slidably fitted on the tie bolt 38 as shown by an arrow A, can be fixed at any position by a screw, and the built-in magnet is sensitive to the approach of the piston which is a magnetic body. The contacts are then closed.

Therefore, if the two sensors 29, 29 'are arranged on the desired forward and backward ends of the hydraulic cylinder, and these are moved to desired positions and fixed, the contacts are closed. Based on the detection signal, the control unit 31 causes the first and second switching valves 9,
Since the switching control of 10 is performed as described above, unlike the conventional sensor embedded and fixed in the cylinder tube, the stroke of the cylinder can be freely adjusted with a simple and inexpensive structure to discharge the high-pressure water by the cylinder. Can be adjusted freely.

[0023]

As is apparent from the above description, the ultra-high pressure control device of the present invention is configured to pressurize the water sucked into each plunger chamber to ultra-high pressure by the reciprocating movement of the hydraulic cylinder.
The second booster is connected to the water discharge line, the pressure port is connected to each discharge line of the first and second hydraulic pumps, and the first port is connected to each head chamber side port of the first and second hydraulic cylinders. In addition to having a load port and each outlet port connected to a return line leading to the tank, and providing first and second switching valves having three switching positions of pressurization, pre-pressurization, and suction, A check valve for back pressure setting is provided in the line connecting the rod chamber side port of the second hydraulic cylinder and the return line. The first and second switching valves are connected to the respective lines connecting the second load ports of the first and second switching valves.
Since the check valves are provided so as to prevent the flow toward each of the second switching valves, the load fluctuation of the hydraulic pump is reduced without providing the hydraulic accumulator, and the first hydraulic pump and the first hydraulic cylinder have the same structure. Pre-pressurize the first booster, pressurize,
Since the second booster is driven in the same way by the second hydraulic pump and the second hydraulic cylinder by driving in the suction stroke, the hydraulic pump can be made small in capacity, excessive relief can be suppressed, energy loss can be reduced, and piston speed can be increased. It is possible to move back, and it is possible to reduce the manufacturing cost and downsize the device.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of an ultrahigh voltage generator of the present invention.

FIG. 2 is a diagram showing an operation sequence of the ultrahigh pressure generator.

FIG. 3 is a diagram showing the change over time of the stroke of the hydraulic cylinders of the first and second boosters in FIG.

FIG. 4 is a side view showing an example of a sensor provided in the hydraulic cylinder of the first booster.

FIG. 5 is a circuit diagram showing a conventional ultrahigh voltage generator.

[Explanation of symbols]

1 ... 1st booster, 2 ... 2nd booster, 3a, 3b ... Plunger chamber, 4a, 4b ... Suction check valve, 5a, 5b ... Discharge check valve, 6a, 6b ... Hydraulic cylinder, 8 ... Water discharge line, 9 ... 1st switching valve, 10 ... 2nd switching valve, 11 ... 1st
Hydraulic pump, 12 ... Second hydraulic pump, 13,14 ... Throttle, 14,15 ... Discharge line, 20 ... Return line, 23
… Line, 24… Check valves for setting back pressure, 27,28
... check valve, 32 ... tank, 33 ... opening / closing valve, 34 ... jet nozzle, 35 ... material to be cut, P ... pressure port, R ... outlet port, A ... first load port, B ... second load port,
Ph ... Head chamber side port, Pr ... Rod chamber side port.

 ─────────────────────────────────────────────────── ─── Continued front page (72) Koichi Hayashi, 1-1 Nishiichitsuya, Settsu-shi, Osaka Prefecture Daikin Industries, Ltd. Yodogawa Manufacturing Co., Ltd. (72) Takaaki Noda 1-1, Nishiichitsuya, Settsu-shi, Osaka Prefecture Daikin Yodogawa Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. A first booster (1) for pressurizing water sucked into a water pressurizing plunger chamber (3a, 3b) by a reciprocating motion of a hydraulic cylinder (6a, 6b) and discharging the water to a water discharge line (8).
And the second booster (2), the first hydraulic pump (11) and the second hydraulic pump (12), and the discharge lines of the first and second hydraulic pumps (11, 12)
Each pressure port (P) connected to (15, 16) and each head chamber side port of the first and second hydraulic cylinders (6a, 6b)
Each first load port (A) connected to (Ph) and the tank (3
The first switching valve (9) and the second switching valve having the respective outlet ports (R) connected to the return line (20) leading to 2) and having three switching positions of pressurization, pre-pressurization and suction. Valve (10)
And a line (2) connecting the rod chamber side ports (Pr) of the first and second hydraulic cylinders (6a, 6b) and the return line (20).
3) The check valve (24) for setting back pressure, which is interposed in the line (23), and the check valve (24) for setting back pressure in the line (23), which is closer to the hydraulic cylinder than the first and second switching valves (9). , 10) to each line (25, 26) connecting each second load port (B),
An ultrahigh pressure generator comprising: a check valve (27, 28) interposed so as to prevent a flow toward each of the first and second switching valves (9, 10).