JP3290804B2 - Intensifier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure intensifier, and more particularly, to a pressure intensifier capable of increasing pressure-increasing efficiency and discharge efficiency.

[0002]

2. Description of the Related Art Generally, in a factory, hydraulic pressure is used for, for example, clamping of a formwork and clamping of a work. However, piping high-pressure hydraulic piping throughout the factory is disadvantageous in terms of equipment costs. Not only that, it is disadvantageous for maintenance. In order to eliminate such a problem, many factories use a so-called intensifier to supply high-pressure oil only where high-pressure oil is required.

As shown in FIG. 3, for example, a conventional pressure intensifier has a cylindrical pressure intensifying chamber 103 having an inlet 101 for sucking hydraulic oil and an outlet 102 for discharging pressurized hydraulic oil.
A suction check valve 104 for opening and closing the inlet 101 is inserted into the inlet and outlet so as to be able to advance and retreat, and the outlet 102 is connected to the discharge check valve 10.
5 is connected. The suction check valve 104 has a cylindrical plunger chamber 106 recessed from the side opposite to the inlet, and the plunger chamber 106 is always connected to the outlet 102 of the pressure increasing chamber 103 through a communication hole 107. .

[0004] A plunger 108 is inserted into the plunger chamber 106 so as to be able to advance and retreat.
As shown in FIG.
The pressure in the plunger chamber 106 is reduced by retracting in the direction in which the volume of the plunger chamber 106 is increased. Hydraulic fluid is sucked into the pressure-intensifying chamber 103.

[0005] Thereafter, as shown in FIG.
When 08 enters the plunger chamber 106, the internal pressure of the plunger chamber 106 is increased, the suction check valve 104 is closed, and as shown in FIG.
And the operating oil in the pressure intensifying chamber 103 is increased, and
Then, the discharge check valve 105 is opened to discharge to the load circuit.

The means for driving the plunger 108 includes:
Although not particularly limited, a reciprocating motion generating engine 11 driven by air taken out from a pressurized air pipe provided in a factory
0 is frequently used. The reciprocating engine 110 is inserted into the cylinder chamber 111 so as to be able to advance and retreat, and is integrally connected to the plunger 108. And a piston 112.

Further, the reciprocating motion generating engine 110 is configured such that the cylinder chamber 111 is provided with a supply port 113 for pressurized air and an exhaust port 1.
14, and a pilot valve 116 for driving the directional control valve 115.
And The pilot valve 116 is driven by a piston 112 to connect a pilot pressure receiving chamber 117 partitioned below the direction control valve 115 to a supply port 113 and an exhaust port 1.
A switching connection is made with an exhaust passage 118 communicating with the exhaust passage.

First, as shown in FIG. 3, when the pilot valve 116 rises to connect the pilot pressure receiving chamber 117 to the supply port 113, the direction control valve 115 is driven upward by the internal pressure of the pilot pressure receiving chamber 117. The supply port 113 is connected to the cylinder chamber 11 through the directional control valve chamber 119.
1, whereby pressurized air is introduced into the cylinder chamber 111, and the piston 112 moves downward against the return spring 120.

As shown in FIG. 4, when the piston 112 descends by a certain amount or more, the pilot valve 116
2, the pilot pressure receiving chamber 117 is communicated with the exhaust port 114 via the exhaust path 118, and the directional control valve 115 is moved downward by the pressure of the pressurized air acting on the directional control valve 115 from the directional control valve chamber 119. And the cylinder chamber 111 is communicated with the exhaust port 114. As a result, the pressure in the cylinder chamber 111 is reduced to the atmospheric pressure, and as shown in FIG.
2 is driven upward.

When the piston 112 moves upward by a certain amount or more, the pilot valve 116 is driven upward by the piston 112, and the direction control valve 115 is switched again to the position shown in FIG. By repeating such a series of operations, the piston 112 reciprocates up and down, and the plunger 108 moves in the plunger chamber 106 integrally with the piston 112.

When the internal pressure of the pressure-increasing chamber 103 reaches a predetermined pressure, the plunger 108 is restricted from lowering by the internal pressure of the plunger chamber 106.
The sum of the pressure of the return spring 120 and the pressure of the cylinder chamber 111
The piston 112 and the plunger 108 stop when the pressure acting on the piston 112 is balanced. And
The suction check valve 104 is urged to a closed position by a suction check valve spring 109.

By the way, in recent pneumatic equipment, in order to achieve both miniaturization and high performance, the air pressure is set to 25 to 50 kg / cm ² which is much higher than the conventional pressure of about 5 to 8 kg / cm ^2.
It is required to increase the pressure to about cm ² , and it is difficult to increase the pressure to such a high pressure with a pressure intensifier that directly increases the hydraulic oil using a conventional reciprocating engine. Therefore, the present inventor has found that the compression of air, which is a compressible fluid, is much easier than the compression of hydraulic oil, which is a non-compressible fluid, and that the working compressed fluid, whose pressure has been increased to about 25 to 50 kg / cm ² , And tried to increase the pressure of air, which is a compressible fluid, by compressing air with a pressure booster having a structure similar to that of hydraulic oil, which is a conventional non-compressed fluid. .

[0013]

However, in this conventional pressure intensifier, since the inlet 101 of the pressure intensifying chamber 103 is communicated with, for example, a hydraulic oil tank, the cylinder chamber 111 is not provided.
The return spring 120 is used to raise the piston 112 and the plunger 108 when the piston is in communication with the exhaust port 114.
The return spring 120 has a problem in that when the piston 112 and the plunger 108 are lowered, the deflection increases and the spring load increases.

Further, since the suction check valve spring 109 is provided in the plunger chamber 106, the gap volume of the plunger chamber 106 with respect to the stroke movement volume of the plunger 108.
There is also a problem that the ratio of (waste volume) is large and the ejection effect is reduced. The present invention has been made in view of the above circumstances, and has as its object to solve a technical problem of providing a pressure intensifier capable of increasing discharge efficiency.

[0015]

According to the present invention, a piston is reciprocated by alternately switching the supply and discharge of a pressure fluid acting on the piston by a directional control valve, and the switching of the directional control valve is performed by reversing the reciprocating motion of the piston. In order to achieve the above-mentioned object, the following means are employed in a pressure intensifier which reciprocates a plunger connected to the piston by switching a pilot flow path by a pilot valve switched by a piston.

That is, the first intensifier according to the present invention comprises:
A cylindrical pressure intensifying chamber having an inlet and an outlet, an injection check valve that opens and closes the inlet and slides and retracts the plunger from the side opposite to the inlet, a discharge check valve connected to the outlet, and a plunger. A cylindrical plunger chamber communicating with the inlet side portion of the pressure intensifying chamber is formed in the injection check valve to be slid into and recessed, and an annular friction member is provided on one of the tip of the plunger and the peripheral surface of the plunger chamber. The friction member is brought into contact with the plunger tip or the inner peripheral surface of the injection check valve in the plunger chamber at a predetermined contact pressure, a pressurized fluid supply source is connected to the inlet, and the injection check valve is opened. Then, the pressurized fluid flows into the plunger chamber to press the plunger, whereby the piston is reciprocated by the reaction force applied to the piston and the supply and exhaust of the pressurized fluid acting on the piston by the directional control valve to increase the pressure. And wherein the Rukoto.

Further, a third technical means according to the present invention is such that a pressurized fluid supply source is connected to the inlet and one of the tip of the plunger and the peripheral surface of the plunger chamber is replaced with the frictional body. A latch member is provided, and an engagement groove in which the latch member is disengaged is provided on the other side.

[0018]

In the first pressure intensifier of the present invention, a pressurized fluid supply source is connected to the inlet, the injection check valve is opened and closed, pressurized fluid flows into the plunger chamber, and the plunger is pressed. Accordingly, the piston is reciprocated by the reaction force applied to the piston and the supply and exhaust of the pressure fluid acting on the piston by the directional control valve to increase the pressure.

In the first pressure intensifier of the present invention,
The friction member externally fitted to the distal end of the plunger is brought into contact with the plunger distal end or the inner peripheral surface of the injection check of the plunger chamber with a predetermined contact pressure, so that the frictional body is generated between the plunger chamber of the suction check valve and the friction body. The suction check valve moves in and out of the booster chamber in conjunction with the operation of the plunger due to frictional force.
As a result, the suction check valve opens and closes the inlet of the pressure increasing chamber.

Further, in the second pressure intensifier of the present invention, the suction check valve advances and retreats in the pressure intensifying chamber in conjunction with the operation of the plunger due to the engagement between the latch member and the engagement groove, and the inlet of the pressure intensifying chamber. Will be opened and closed. And the first of the present invention
In the pressure intensifier described above, the plunger is urged in the direction of withdrawing from the plunger chamber by the pressurized air supplied from the inlet to the plunger chamber through the pressure intensifying chamber, so that the plunger is urged in the direction of withdrawing from the plunger chamber. The return spring can be omitted, and a decrease in the pressure increasing efficiency due to the resistance of the return spring can be eliminated.

In the first pressure booster and the second pressure booster according to the present invention, the injection check valve spring is omitted, the plunger can be in close contact with the inner periphery of the injection check valve, and the plunger chamber with respect to the stroke movement volume of the plunger. The ratio of the void volume (waste volume) can be reduced, and a decrease in the discharge efficiency can be prevented.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a pressure intensifier according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings.
The present invention is not limited to this embodiment, but extends to the whole range of the technical idea that is truly intended by the present invention, which is apparent from the entire description of the present specification and the accompanying drawings.

The pressure intensifier according to the embodiment of the present invention shown in the sectional views of FIGS. 1 and 2 alternately switches the supply and discharge of the pressurized fluid acting on the piston 12 by the directional control valve 15. The piston reciprocates and switches the direction control valve 15 by reversing the reciprocating motion of the piston 12 by switching the pilot flow path 21 by the pilot valve 16 switched by the piston 12 to reciprocate the plunger 8 connected to the piston 12. An injection check valve 4 and a discharge check valve 5 for moving, injecting the pressurized fluid flowing into the plunger chamber 6 from a certain direction, increasing the pressure, and discharging the same are provided.

A cylindrical pressure intensifying chamber 3 having an inlet 1 and an outlet 2, an injection check valve 4 for opening and closing the inlet 1 and slidingly plunging the plunger 8 from the side opposite to the inlet 1;
A cylindrical plunger chamber 6 is formed in a discharge check valve 5 connected to the outlet 2 and an injection check valve 4 for slidingly plunging a plunger 8, the cylindrical plunger chamber 6 communicating with the inlet side of the pressure intensifying chamber 3. An annular friction body is fitted to one of the tip and the peripheral surface of the plunger chamber, and brought into contact with the plunger tip or the peripheral surface of the plunger chamber with a predetermined contact pressure of the friction body,
The injection check valve 4 is opened, a pressurized fluid flows into the plunger chamber 6, a pressurized fluid supply source is connected to the inlet 1, and the plunger 8 is pressed.
The piston 12 is reciprocated by the supply and exhaust of the pressure fluid acting on the piston 12 by the directional control valve 15 and the plunger 8 connected to the piston 12 is reciprocated to increase the pressure.

At the tip of the plunger 8, for example, O
A friction body 9 made of a ring is fitted on the outside, and the friction body 9 is slidably brought into contact with the inner peripheral surface of the injection check valve 4 of the plunger chamber 6 at a predetermined contact pressure. This pressure intensifier includes a reciprocating motion generating engine 10 for driving the plunger 8. The reciprocating motion generating engine 10 has a reciprocating motion used in a conventional pressure intensifier except that a return spring 120 is omitted. It is configured similarly to the generating engine 10.

That is, a cylindrical cylinder chamber 11 coaxial with the pressure increasing chamber 3 and the plunger chamber 6, a piston 12 inserted into the cylinder chamber 11 so as to be able to advance and retreat, and integrally connected to the plunger 8, A directional control valve 15 for switchingly connecting the cylinder chamber 11 to a supply port 13 and an exhaust port 14 for pressurized air, and a pilot valve 16 for driving the directional control valve 15 are provided.

The pilot valve 16 is used for the piston 1
2, the pilot pressure receiving chamber 17 partitioned below the direction control valve 15 is switched and connected to the supply port 13 and the exhaust path 18 communicating with the exhaust port 14. The inlet 1 of the pressure increasing chamber 3 and the supply port 13 of the reciprocating motion generating engine 10 are connected to a common or separate pressurized air supply source.

Reference numeral 19 denotes a directional control valve chamber which is always in communication with the supply port 13 and is connected to the cylinder chamber 11 depending on the position of the directional control valve 15 or is connected to the cylinder chamber 1.
Blocked from 1. In this pressure intensifier, first, as shown in FIG. 1, when the pilot valve 16 rises and connects the pilot pressure receiving chamber 17 to the supply port 13, the direction control valve 15 is driven upward by the internal pressure of the pilot pressure receiving chamber 17. , The supply port 13 is communicated with the cylinder chamber 11 via the direction control valve chamber 19, whereby pressurized air is introduced into the cylinder chamber 11 to lower the piston 12 and the plunger 8 against the internal pressure of the plunger chamber 6. Will be moved.

At the tip of the plunger 8, a plunger chamber 6 is provided.
Is provided with a frictional body 9 which comes into contact with a predetermined contact pressure on the inner peripheral surface of the valve, so that the injection check valve 4 is lowered as the plunger 8 is lowered, and the inlet 1 is closed. Therefore, there is no danger that the discharge efficiency will decrease due to the delay in closing the injection check valve 4. After that, when the plunger 8 further lowers, the internal pressures of the plunger chamber 6 and the pressure increasing chamber 3 increase, and the discharge check valve 5 opens. The valve is vented and the increased pressure air is discharged to the load circuit.

As shown in FIG. 2, when the piston 12 descends by a certain amount or more, the pilot valve 16 is driven downward by the piston 12, and the pilot pressure receiving chamber 17
8 communicates with the exhaust port 14 and the intake port 13 communicates with the direction control valve chamber 19. Thereby, the direction control valve 15
The direction control valve 15 is moved downward by the internal pressure of the direction control valve chamber 19, and the cylinder chamber 11 is communicated with the exhaust port 14. Thus, the pressure in the cylinder chamber 11 is reduced to the atmospheric pressure, and the plunger 8 and the piston 12 are driven upward by the internal pressure of the plunger chamber 6.

What is important here is that the plunger 8 and the piston 12 are driven upward by the internal pressure of the plunger chamber 6, thereby eliminating the need for a return spring for urging the plunger 8 and the piston 12 upward. It is becoming. As a result, the pressure increase efficiency can be improved by eliminating the resistance of the spring load that is unnecessarily increased due to the increase in the deflection of the return spring when the piston 12 and the plunger 8 are lowered.

When the piston 12 and the plunger 8 rise upward, the injection check valve 4 also rises along with the plunger 8, but at this time, since the discharge check valve 5 closes, the pressure on the load circuit side decreases. It is not. In this intensifier, the fluid to be increased in pressure is air,
Particularly suitable for use in textile factories, food factories, pharmaceutical factories, etc., where the use of oil is avoided.

Further, in the above-described embodiment, the plunger 8 is driven by the pneumatic reciprocating motion generating engine 10. However, for example, a hydraulic reciprocating motion generating engine using pressure oil as a driving source instead of pressurized air is used. To drive the plunger 8 or to connect a pressure oil supply source to the inlet of the pressure intensifier 3. In addition, in the above-described embodiment, the friction body 9 is externally fitted to the tip of the plunger 8, and the frictional force of the friction body 9 causes the injection check valve 4 to move.
, But instead of this friction body 9,
The plunger 8 is biased by a spring to support a latch member such as a ball that protrudes and retracts toward the peripheral surface of the plunger chamber 6 and a leaf spring that protrudes and retracts toward the peripheral surface of the plunger chamber 6. It is also possible to form an engagement groove in which the latch member is engaged and disengaged, and the injection check valve 4 is driven by the plunger 8 by the engagement.

Of course, the latch member may be provided so as to protrude and retract from the peripheral surface of the plunger chamber 6 toward the plunger 8, and the plunger 8 may be provided with an engagement groove for engaging and disengaging the latch member.

[0035]

As described above, according to the pressure intensifier of the present invention, the injection check valve is closed in conjunction with the lowering of the plunger by the frictional force of the friction body or the engagement of the latch member with the engagement groove. Since the valve is opened, the discharge efficiency does not decrease due to the delay in closing the injection check valve.

Further, according to the pressure intensifier of the present invention, since the pressurized fluid supply source is connected to the inlet of the pressure intensifying chamber, the plunger is urged by the pressurized fluid in the direction of withdrawing from the plunger chamber. Omitting a return spring that urges the plunger in a direction to exit the plunger chamber and increasing the deflection when the plunger enters the plunger chamber, reducing the resistance of the spring load that is unnecessarily increased and increasing the pressure boosting efficiency. You can do it.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a transition from an injection process to a discharge process according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a transition from a discharge process to an injection process according to an embodiment of the present invention.

FIG. 3 is a sectional view of a conventional discharge stroke.

FIG. 4 is a sectional view of a conventional ejection process.

FIG. 5 is a sectional view of a conventional suction stroke.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Inlet 2 ... Outlet 3 ... Pressure increasing chamber 4 ... Injection check valve 5 ... Discharge check valve 6 ... Plunger chamber 8 ... Plunger 9 ... Friction body 10 ... Reciprocating motion generating engine 20 ... Discharge port

────────────────────────────────────────────────── ─── Continued on the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) F04B 1/00-19/24 F04B 23/00-23/04 F04B 53/00-53/22

Claims (2)

(57) [Claims] A pilot which reciprocates a piston by alternately switching the supply and discharge of a pressure fluid acting on the piston by a directional control valve, and switches the directional control valve by the piston by reversing the reciprocation of the piston. A pressure intensifier is provided by switching a pilot flow path by a valve, and reciprocates a plunger connected to the piston. The pressure intensifier has a cylindrical pressure increasing chamber having an inlet and an outlet, and is slidably provided in the pressure increasing chamber. An injection check valve for opening and closing the inlet and recessing the plunger from the side opposite to the inlet, a discharge check valve connected to the outlet, and an inlet side of the pressure increasing chamber in the injection check valve for slidingly recessing the plunger. A cylindrical plunger chamber communicating with the plunger chamber is formed, and an annular friction body is fitted to one of the tip of the plunger and the peripheral surface of the plunger chamber. Contact the plunger tip or the peripheral surface of the plunger chamber with a predetermined contact pressure, connect a pressurized fluid supply source to the inlet, open the injection check valve, allow the pressurized fluid to flow into the plunger chamber, A pressure intensifier characterized in that the pressure is increased by reciprocating the piston by a reaction force applied to the piston by pressing the plunger and a supply and exhaust of the pressure fluid acting on the piston by the direction control. 2. A latch member is provided at one of a tip end of a plunger and a peripheral surface of a plunger chamber, instead of the friction body.
2. The pressure intensifier according to claim 1, further comprising an engagement groove on the other side where the latch member is engaged and disengaged.