KR102523626B1 - pressure intensifier - Google Patents

Abstract

The pressure intensifier (10) has drive cylinders (14, 16) arranged on both sides of a pressure booster cylinder (12), and a knock pin (90) with which the pistons (36, 38) of the drive cylinder abut at their moving ends. A pair of pilot valves 72 and 74 having a and a pair of operation valves 48 and 52 for switching the supply state of the pressure fluid to the pressurized chambers 24a and 26a of the driving cylinder, When the pilot valve on one side or the other side is switched to the first position by pressing the knock pin by the piston, the state in which the pressure fluid is supplied to the pair of operation valves is switched, and the pilot valve is maintained at the first position. Pressure acts on the knock pin.

Description

pressure intensifier

The present invention relates to a pressure intensifying device that boosts and outputs a pressure fluid.

BACKGROUND OF THE INVENTION [0002] Conventionally, a pressure intensifying device that continuously increases and outputs pressure fluid by reciprocating motion of a piston is known.

For example, in Japanese Unexamined Patent Publication No. 8-21404, a pair of cylinders for pressure intensification, each of which is directly connected to a piston rod, is arranged to face each other, and an energy recovery function is provided between the pair of cylinders for pressure intensification. A pressure intensifier equipped with a cylinder is described. This pressure intensifier pressurizes and outputs the air entering the compression chamber of one pressure boosting cylinder by introducing compressed air into the compression chamber and operating chamber of one pressure boosting cylinder and the compression chamber of the other pressure boosting cylinder. The supply air switching operation to the pressure boosting cylinder and the flow path switching operation to the recovery cylinder are performed by detecting the piston position of the pressure boosting cylinder with a reed switch and turning on/off the solenoid of the selector valve.

In the pressure intensifier disclosed in Japanese Unexamined Patent Publication No. Hei 8-21404, an operating chamber for driving a piston and a compression chamber for compressing a fluid are provided in a pair of pressure intensifying cylinders, which may limit the degree of freedom in design. . In addition, since a reed switch and a solenoid are used to perform the switching operation, electrical means including electric wiring are required.

Here, the present applicant patents the invention of a pressure intensifier capable of performing a switching operation without relying on electrical means while separately installing a cylinder for driving a piston and a cylinder for compressing a pressurized fluid and arranging them organically. An application was filed (Japanese Patent Application No. 2017-164945).

The pressure intensifying device according to the above patent application includes a pair of pilot valves having driving cylinders arranged on both sides of the pressure increasing cylinder, and a push rod to which a piston of the driving cylinder comes into contact at its moving end, and pressurization of the driving cylinder. A pair of operation valves are provided for switching the supply state of the pressure fluid from the pressure fluid supply source to the chamber.

In the pressure intensifier according to the above patent application, when the output of the pressure intensifier approaches saturation, for example, when the piston of the drive cylinder weakens the force pressing the push rod and the pilot valve is not sufficiently switched, the push rod moves through the spring force. , and it was not always possible to be satisfied. The present invention has been made against the backdrop of such circumstances, and an object of the present invention is to provide a pressure intensifying device capable of reliably switching a pilot valve even when the force of a piston of a driving cylinder presses the pilot valve is weak.

A pressure intensifying device according to the present invention has driving cylinders arranged on both sides of a pressure increasing cylinder, a pair of pilot valves having knock pins with which a piston of the driving cylinder contacts at its moving end, and pressurization of the driving cylinder. A pair of operation valves are provided for switching the supply state of the pressure fluid from the pressure fluid supply source to the chamber. And, when the pilot valve on one side or the other side is switched to the first position by pressing the knock pin by the piston, the state in which the pressure fluid is supplied to the pair of operation valves is switched, and the pilot valve is maintained at the first position. of fluid pressure acts on the knock pin.

According to the pressure intensifying device, the knock pin in contact with the piston of the driving cylinder can be pushed to the end with a predetermined fluid pressure, so that the pilot valve can be maintained in a sufficiently switched position.

According to the pressure intensifier according to the present invention, since a predetermined fluid pressure acts on the knock pin so that the pilot valve is maintained at the switched position, even if the force of the piston of the driving cylinder presses the knock pin is weak, the knock pin is pushed all the way. I can attach it and can change a pilot valve surely.

1 is an external perspective view of a pressure intensifier according to an embodiment of the present invention.
Figure 2 is a side view of the pressure intensifier of Figure 1;
FIG. 3 is a III-III sectional view of FIG. 2 .
4 is a IV-IV sectional view of FIG. 2 .
5 is an overall schematic diagram of the pressure intensifier of FIG. 1 using a circuit diagram.
6 is a cross-sectional view of the first pilot valve of the pressure booster of FIG. 1;
Fig. 7 is a view corresponding to Fig. 6 when the knock pin of the first pilot valve is moved to another position.
Fig. 8 is a view corresponding to Fig. 6 when the knock pin of the first pilot valve is moved to another position.
FIG. 9 is a view corresponding to FIG. 5 when the pressure intensifying device transitions from the state of FIG. 5 to another state.

Hereinafter, a preferred embodiment of the pressure intensifier according to the present invention will be described in detail with reference to the accompanying drawings. The pressure intensifying device 10 according to the embodiment of the present invention is arranged between an unillustrated pressurized fluid supply source (pressure) and an unillustrated actuator operated by the increased pressure fluid.

As shown in FIGS. 1 and 3 , the pressure intensifying device 10 includes first driving cylinders 14 on one end side (A1 direction side) and the other end side (A2 direction side) of the pressure increasing cylinder 12, respectively. And it has a three-component cylinder structure in which the second driving cylinders 16 are installed in succession. That is, in the pressure intensifying device 10, the first driving cylinder 14, the pressure increasing cylinder 12, and the second driving cylinder 16 are installed consecutively in this order from the direction A1 to the direction A2.

A block-shaped first cover member 18 is inserted between the first driving cylinder 14 and the pressure boosting cylinder 12, and between the pressure boosting cylinder 12 and the second driving cylinder 16 A block-shaped second cover member 20 is inserted.

A pressure increasing chamber 22 is formed inside the pressure increasing cylinder 12, and a first driving chamber 24 and a second driving chamber 24 are formed inside the first driving cylinder 14 and the second driving cylinder 16, respectively. A thread 26 is formed. In this case, the third cover member 28 is fixed to the end of the first driving cylinder 14 in the A1 direction, and the first cover member 18 is arranged at the end in the A2 direction, so that the first drive chamber (24) is formed. In addition, the second cover member 20 is arranged at the end of the second driving cylinder 16 in the A1 direction, and the end in the A2 direction is closed with the wall portion 30, so that the second drive chamber 26 is formed. is formed

As shown in FIG. 3 , a piston rod 32 is arranged passing through the first cover member 18 , the pressure increasing cylinder 12 and the second cover member 20 . One end of the piston rod 32 extends into the first driving chamber 24, and the other end of the piston rod 32 extends into the second driving chamber 26.

In the pressure boosting chamber 22, a pressure boosting piston 34 is connected to the central portion of the piston rod 32. Thus, the pressure increasing chamber 22 is partitioned into a first pressure increasing chamber 22a on the A1 direction side and a second pressure increasing chamber 22b on the A2 direction side (see Fig. 5). In the first driving chamber 24, a first driving piston 36 is connected to one end of the piston rod 32. Thus, the first drive chamber 24 is partitioned into a pressure chamber 24a on the A1-direction side and a back-pressure chamber 24b on the A2-direction side (see Fig. 5). Moreover, in the 2nd driving chamber 26, the 2nd driving piston 38 is connected to the other end of the piston rod 32. Thus, the second drive chamber 26 is divided into a pressure chamber 26a on the A2-direction side and a back-pressure chamber 26b on the A1-direction side (see Fig. 5). The piston for pressure increase 34, the 1st piston for drive 36, and the 2nd piston for drive 38 are integrally connected via the piston rod 32.

As shown in FIG. 1, a supply port 40 through which pressure fluid is supplied from a pressure fluid supply source (not shown) is formed on the front upper portion of the pressure increasing cylinder 12. 4 and 5, inside the pressure increasing cylinder 12, the first cover member 18, and the second cover member 20 communicate with the supply port 40, and the pressure fluid is supplied thereto. A fluid supply mechanism is provided to supply the first pressure increasing chamber 22a and the second pressure increasing chamber 22b. The fluid supply mechanism includes a first supply flow path 42a communicating between the supply port 40 and the first pressure increasing chamber 22a, and a second supply flow path communicating between the supply port 40 and the second pressure increasing chamber 22b. (42b).

In the first supply passage 42a, a flow of fluid from the supply port 40 to the first pressure increasing chamber 22a is allowed, and a flow of fluid from the first pressure increasing chamber 22a to the supply port 40 is allowed. A first supply check valve 42c for blocking is provided. In the second supply passage 42b, the flow of fluid from the supply port 40 to the second pressure increasing chamber 22b is allowed, and the flow of fluid from the second pressure increasing chamber 22b to the supply port 40 is allowed. A blocking second supply check valve 42d is provided.

As shown in FIG. 1 , an output port 44 is formed at the lower front surface of the pressure increasing cylinder 12 to output the fluid increased in pressure by a pressure increasing operation described later to the outside. 4 and 5, inside the pressure increasing cylinder 12, the first cover member 18 and the second cover member 20 communicate with the output port 44, and the first pressure increasing chamber 22a or a fluid output mechanism for outputting the fluid pressure-increased in the second pressure-increasing chamber 22b from the output port 44 is provided. The fluid output mechanism includes a first output flow path 46a communicating between the first pressure increasing chamber 22a and the output port 44, and a second output flow path communicating between the second pressure increasing chamber 22b and the output port 44. (46b).

The first output passage 46a allows the flow of fluid from the first pressure boosting chamber 22a to the output port 44, and allows the flow of fluid from the output port 44 to the first pressure boosting chamber 22a. A blocking first output check valve 46c is provided. In the second output passage 46b, the flow of fluid from the second pressure boosting chamber 22b to the output port 44 is allowed, and the flow of fluid from the output port 44 to the second pressure boosting chamber 22b is allowed. A blocking second output check valve 46d is provided.

Next, the configuration of the operating valve will be described. As shown in FIG. 1, a first housing 50 having a first operating valve 48 is arranged on the upper part of the first driving cylinder 14, and an upper part of the second driving cylinder 16 At , a second housing 54 with a second operating valve 52 is arranged.

As shown in FIG. 5 , the first operation valve 48 has first ports 56A to fifth ports 56E as connection and switching points of flow passages, and drives the first driving piston 36. It is configured so as to be switchable between a first position for driving and a second position for driving the first driving piston 36 in accordance with the driving of the second driving piston 38.

The 1st port 56A is connected to the pressurization chamber 24a of the 1st drive cylinder 14 by the flow path 58a. The second port 56B is connected to the back pressure chamber 24b of the first driving cylinder 14 via a flow path 58b. The 3rd port 56C is connected to the 1st supply flow path 42a by the flow path 58c. The fourth port 56D is connected to the first silencer 62 equipped with a discharge port through a flow path 58d. The fifth port 56E is connected halfway to the flow path 58a by the flow path 58e. A first fixed orifice 60 is interposed in the passage 58d.

When the first operating valve 48 is in the first position, the first port 56A and the third port 56C are connected, and the second port 56B and the fourth port 56D are connected. . As a result, the pressure fluid from the supply port 40 is supplied to the pressure chamber 24a through the passage 58c and the passage 58a, and the fluid in the back pressure chamber 24b passes through the passage 58b and the passage ( 58d) and is discharged through the first fixed orifice 60 and the first silencer 62.

When the first operation valve 48 is in the second position, the first port 56A and the fourth port 56D are connected, and the second port 56B and the fifth port 56E are connected. . As a result, part of the fluid in the pressure chamber 24a passes through the flow passage 58a, flow passage 58e, and flow passage 58b to be returned to the back pressure chamber 24b, and the rest passes through the flow passage 58d to return to the first pressure chamber 24b. It is discharged through the fixed orifice 60 and the first silencer 62.

The 1st operation valve 48 also has a pilot port 56F for introducing pilot pressure from the 2nd pilot valve 74 mentioned later. The first operating valve 48 is in the first position when pressure fluid (pilot pressure) is supplied to the pilot port 56F, and when pressure fluid (pilot pressure) is not supplied to the pilot port 56F. It is in the second position.

The 2nd operation valve 52 has the 1st port 64A to the 5th port 64E as a connection and switching point of a flow path, and the 1st position for driving the 2nd driving piston 38 and a 1st drive It is comprised so that switching is possible between the 2nd position for driving the 2nd piston 38 for a drive along with the drive of the piston 36 for drive.

The 1st port 64A is connected to the pressurization chamber 26a of the 2nd driving cylinder 16 by the flow path 66a. The second port 64B is connected to the back pressure chamber 26b of the second driving cylinder 16 via a flow path 66b. The third port 64C is connected to the second supply flow path 42b through the flow path 66c. The fourth port 64D is connected to the second silencer 70 equipped with a discharge port through a flow path 66d. The fifth port 64E is connected halfway to the flow path 66a by the flow path 66e. A second fixed orifice 68 is interposed in the passage 66d.

When the second operation valve 52 is in the first position, the first port 64A and the third port 64C are connected, and the second port 64B and the fourth port 64D are connected. . As a result, the pressure fluid from the supply port 40 is supplied to the pressure chamber 26a through the passage 66c and the passage 66a, and the fluid in the back pressure chamber 26b passes through the passage 66b and the passage ( 66d) and is discharged through the second fixed orifice 68 and the second silencer 70.

When the second operation valve 52 is in the second position, the first port 64A and the fourth port 64D are connected, and the second port 64B and the fifth port 64E are connected. . As a result, a part of the fluid in the pressure chamber 26a passes through the passage 66a, the passage 66e, and the passage 66b to be returned to the back pressure chamber 26b, and the rest passes through the passage 66d to return to the second pressure chamber 26b. It is discharged through the fixed orifice 68 and the second silencer 70.

The 2nd operation valve 52 also has a pilot port 64F for introducing pilot pressure from the 1st pilot valve 72 mentioned later. The second operation valve 52 is in the first position when pressure fluid (pilot pressure) is supplied to the pilot port 64F, and when pressure fluid (pilot pressure) is not supplied to the pilot port 64F. It is in the second position.

Next, the configuration of the pilot valve will be described. A first pilot valve 72 is arranged inside the first cover member 18, and a second pilot valve 74 is arranged inside the second cover member 20.

The first pilot valve 72 has a first port 76A to a fourth port 76D, and has a first position for generating a pilot pressure for the second operation valve 52 and a position for dissipating the pilot pressure. It is configured to be switchable between the second position and the second position.

The first port 76A is connected to the pilot port 64F of the second operation valve 52 through the first pilot oil passage 78b. The second port (supply port) 76B is connected to the first supply flow path 42a through a flow path 78a. The third port 76C constitutes an exhaust port. The fourth port (cooperation port) 76D is connected to a first port 80A of a second pilot valve 74 described later by a branch oil passage 82c and a second pilot oil passage 82b described later. are connected Further, a branch oil passage 78c reaching a fourth port 80D of a second pilot valve 74 described later is branched off from the first pilot oil passage 78b and is provided.

When the first pilot valve 72 is in the first position, the first port 76A and the second port 76B are connected. As a result, the pressure fluid from the supply port 40 is supplied to the pilot port 64F of the second operation valve 52 through the passage 78a and the first pilot passage 78b, and the first pilot It is supplied to a fourth port 80D of a second pilot valve 74 described later through a branched flow path 78c branching from the flow path 78b.

When the first pilot valve 72 is in the second position, the first port 76A and the third port 76C are connected. As a result, the pressure fluid supplied to the pilot port 64F of the second operation valve 52 is discharged through the first pilot oil passage 78b, and the fourth port of the second pilot valve 74 ( The pressure fluid supplied to 80D) is discharged through the branch passage 78c and the first pilot passage 78b.

The second pilot valve 74 has a first port 80A to a fourth port 80D, and has a first position for generating a pilot pressure with respect to the first operating valve 48 and a position for dissipating the pilot pressure. It is configured to be switchable between the second position and the second position.

The first port 80A is connected to the pilot port 56F of the first operation valve 48 through the second pilot oil passage 82b. The second port (supply port) 80B is connected to the second supply flow path 42b via the flow path 82a. The third port 80C constitutes an exhaust port. The fourth port 80D (cooperating port) is connected to the first port 76A of the first pilot valve 72 by the branch oil passage 78c and the first pilot oil passage 78b. Further, a branch oil passage 82c reaching the fourth port 76D of the first pilot valve 72 is branched off from the second pilot oil passage 82b.

When the second pilot valve 74 is in the first position, the first port 80A and the second port 80B are connected. As a result, the pressure fluid from the supply port 40 is supplied to the pilot port 56F of the first operation valve 48 through the passage 82a and the second pilot passage 82b, and the second pilot It is supplied to the fourth port 76D of the first pilot valve 72 through the branched flow path 82c branching from the flow path 82b.

When the second pilot valve 74 is in the second position, the first port 80A and the third port 80C are connected. As a result, the pressure fluid supplied to the pilot port 56F of the first operating valve 48 is discharged through the second pilot oil passage 82b, and the fourth port of the first pilot valve 72 ( The pressure fluid supplied to 76D) is discharged through the branch passage 82c and the second pilot passage 82b.

Here, the specific structure of the 1st pilot valve 72 is demonstrated, referring FIGS. 6-8. Note that, since the specific structure of the second pilot valve 74 is the same as that of the first pilot valve 72, description thereof is omitted.

The first pilot valve 72 includes a valve seat 86 accommodated in a valve accommodating hole 84 provided in the first cover member 18, a valve seat retainer 88, and a knock pin 90. The valve accommodating hole 84 is closed on the pressure increasing cylinder 12 side and open on the first driving cylinder 14 side. The closing side end of the valve accommodating hole 84 consists of a large-diameter hole portion 84a, and the fourth port 76D communicates with this large-diameter hole portion 84a.

The valve accommodating hole 84 has a small-diameter hole portion 84b following the large-diameter hole portion 84a and a medium-diameter hole portion 84c on the opening side following the small-diameter hole portion 84b. The first port 76A, the second port 76B, and the third port 76C communicate with the small-diameter hole portion 84b of the valve accommodating hole 84 . Among these three ports, the second port 76B is located closest to the fourth port 76D, and the third port 76C is located farthest from the fourth port 76D.

In the small-diameter hole portion 84b of the valve accommodating hole 84, a cylindrical valve seat 86 having a thin thickness and a valve seat retainer 88 having a thick cylindrical shape are fitted and inserted. The end face of the valve seat retainer 88 on one side in the axial direction faces the back pressure chamber 24b of the first driving cylinder 14, and the end face on the other side in the axial direction abuts against the valve seat 86. A stop ring 92 abutting against the valve seat retainer 88 is fixed to the middle diameter hole portion 84c of the valve receiving hole 84. Thereby, the valve seat 86 and the valve seat retainer 88 are positioned and fixed in the valve receiving hole 84 in the axial direction. Further, the valve seat 86 is engaged with a stepped portion provided in the middle of the small-diameter hole portion 84b.

An annular groove 86a opposing the first port 76A is provided on the outer periphery of the central portion in the axial direction of the valve seat 86, and the valve seat 86 on the side abutting against the valve seat retainer 88 is formed in the axial direction. An annular concave portion 86b facing the third port 76C is provided on the outer periphery of the end portion. The annular groove 86a of the valve seat 86 communicates with the inner circumferential side of the valve seat 86 via a first through hole 86c penetrating the valve seat 86 in the radial direction. The annular concave portion 86b of ) communicates with the inner peripheral side of the valve seat 86 via a second through hole 86d penetrating the valve seat 86 in the radial direction.

On the outer circumferential surface of the valve seat 86, a first sealing material 94a and a second sealing material 94b, which abut against the small-diameter hole portion 84b of the valve receiving hole 84, are attached via grooves, respectively. The first sealing material 94a prevents communication between the first port 76A and the second port 76B through a gap between the valve seat 86 and the valve receiving hole 84, and the second sealing material 94b ) prevents the first port 76A and the third port 76C from communicating through a gap between the valve seat 86 and the valve receiving hole 84.

On the outer circumferential surface of the valve seat retainer 88, a third sealing material 96a, which abuts against the small-diameter hole portion 84b of the valve receiving hole 84, is mounted via a groove, and on the inner circumferential surface of the valve seat retainer 88, a knock A fourth sealing material 96b which is in sliding contact with the pin 90 is mounted through the groove portion. The third sealing material 96a and the fourth sealing material 96b seal between the third port 76C and the back pressure chamber 24b of the first driving cylinder 14 .

The knock pin 90 has a large-diameter shaft portion 90a, a medium-diameter shaft portion 90b, and a small-diameter shaft portion 90c. The large-diameter shaft portion 90a is fitted and inserted into the small-diameter hole portion 84b of the valve accommodating hole 84. The medium-diameter shaft portion 90b is inserted into the valve seat 86 in a state where a portion of it protrudes from the valve seat 86, and the portion that protrudes from the valve seat 86 is the valve receiving hole 84 It opposes the small-diameter hole portion 84b in the radial direction at a predetermined interval. The small-diameter shaft portion 90c is fitted and inserted inside the valve seat retainer 88.

The large-diameter shaft portion 90a of the knock pin 90 is fitted with a first packing 98a that slides into the small-diameter hole portion 84b of the valve accommodating hole 84 via a groove portion. The first packing 98a seals between the second port 76B and the fourth port 76D. A second packing 98b and a third packing 98c capable of sliding contact with the inner circumferential surface of the valve seat 86 are attached to the middle-diameter shaft portion 90b of the knock pin 90 via grooves. On the outer periphery of the middle-diameter shaft portion 90b of the knock pin 90, between the portion where the second packing 98b is attached and the portion where the third packing 98c is attached, an annular groove 90d is formed. It is installed.

In the knock pin 90, there is a gap between the end of the large-diameter shaft portion 90a and the bottom surface (closed end face) of the valve receiving hole 84, and between the medium-diameter shaft portion 90b and the small-diameter shaft portion 90c. It is slidable between the position where the stepped surface 90e abuts against the end surface of the valve seat retainer 88. When the knock pin 90 abuts against the end surface of the valve seat retainer 88, the small-diameter shaft portion 90c of the knock pin 90 protrudes from the back pressure chamber 24b of the first driving cylinder 14. The length (hereinafter referred to as "protrusion length of the knock pin") becomes the maximum. The first driving piston 36 is in contact with the end of the knock pin 90 on the side of the small-diameter shaft portion 90c, and can press the knock pin 90 toward the bottom of the valve receiving hole 84.

Regardless of the protruding length of the knock pin 90, the annular groove 90d of the knock pin 90 communicates with the annular groove 86a via the first through hole 86c of the valve seat 86. . In other words, the annular groove 90d of the knock pin 90 always communicates with the first port 76A regardless of the position of the knock pin 90 . In addition, the second port 76B always communicates with the gap formed between the medium-diameter shaft portion 90b of the knock pin 90 and the small-diameter hole portion 84b of the valve accommodating hole 84. .

When the protruding length of the knock pin 90 is large, the second packing 98b comes into contact with the inner surface of the valve seat 86 and the third packing 98c separates from the inner surface of the valve seat 86 (Fig. see 6). Therefore, the first port 76A is the gap between the knock pin 90 including the annular groove 90d of the knock pin 90 and the inner surface of the valve seat 86, and the second port of the valve seat 86. It communicates with the third port 76C through the through hole 86d and the annular concave portion 86b.

When the first driving piston 36 abuts against the knock pin 90 and the protruding length of the knock pin 90 is slightly reduced than above, both the second packing 98b and the third packing 98c are valve seats. It abuts on the inner surface of (86) (see FIG. 7). Therefore, the 1st port 76A communicates with neither the 2nd port 76B nor the 3rd port 76C.

When the protruding length of the knock pin 90 is small, the second packing 98b moves away from the inner surface of the valve seat 86, and the third packing 98c abuts on the inner surface of the valve seat 86 (Fig. 8). Therefore, the first port 76A has a gap between the knock pin 90 including the annular groove 90d of the knock pin 90 and the inner surface of the valve seat 86 and the middle diameter of the knock pin 90. It communicates with the second port 76B through a gap formed between the shaft portion 90b and the small-diameter hole portion 84b of the valve accommodating hole 84.

When pressurized fluid is supplied to the fourth port 76D, the knock pin 90 is pressed in a direction in which the protrusion length increases. The reason for this is that the area (pressure receiving area) where the fluid pressure of the fourth port 76D applied in the direction of increasing the protrusion length of the knock pin 90 acts in the direction of decreasing the protrusion length of the knock pin 90 This is because the fluid pressure applied to the second port 76B is greater than the acting area (pressure receiving area).

On the other hand, when the pressurized fluid is not supplied to the fourth port 76D, the knock pin 90 is pressed in a direction in which the protrusion length decreases. The reason is that the fluid pressure of the fourth port 76D applied in the direction of increasing the protrusion length of the knock pin 90 is lost, while the second pressure applied in the direction of reducing the protrusion length of the knock pin 90 is lost. This is because the fluid pressure of the port 76B is maintained.

The pressure intensifier 10 according to the first embodiment of the present invention is basically configured as described above, and its operation and effect will be described next. As shown in FIG. 5 , the first operation valve 48 is in a state of being switched to the second position and the second operating valve 52 is in a state of being switched to the first position, and the pressure-increasing piston 34 ) is located near the center of the pressure increasing chamber 22 as the initial position. In the following description, in order to distinguish between the knock pin of the first pilot valve 72 and the knock pin of the second pilot valve 74, the former is referred to as "knock pin 90-1" and the latter as "knock pin 90-1". Pin 90-2". In addition, in order to distinguish between the valve accommodating hole of the first pilot valve 72 and the valve accommodating hole of the second pilot valve 74, the former is referred to as "valve accommodating hole 84-1" and the latter is referred to as "valve accommodating hole ( 84-2)”.

In this initial position, by supplying the pressure fluid from the pressure fluid supply source to the supply port 40, the pressure fluid flows into the first supply passage 42a and the second supply passage 42b. Then, it is introduced into the first pressure increasing chamber 22a and the second pressure increasing chamber 22b of the pressure increasing cylinder 12 through the first supply check valve 42c and the second supply check valve 42d.

A part of the pressure fluid supplied from the supply port 40 passes through the flow path 66c, the second operation valve 52 in the first position and the flow path 66a, and pressurizes the second driving cylinder 16. It is supplied to yarn 26a. The second driving piston 38 is driven in the A1 direction by the pressure fluid supplied to the pressure chamber 26a. As a result, the pressure boosting piston 34 integrally connected to the second drive piston 38 slides, and the pressure fluid in the first pressure boosting chamber 22a of the pressure boosting cylinder 12 is increased. This increased pressure fluid passes through the first output passage 46a and the first output check valve 46c, is led to the output port 44, and is output.

On the other hand, when the first driving piston 36 integrally connected to the second driving piston 38 slides, the volume of the pressure chamber 24a of the first driving cylinder 14 decreases. Since the first operating valve 48 is in the second position, a part of the pressure fluid in the pressurized chamber 24a passes through the flow path 58a, the flow path 58e and the flow path 58b to the back pressure chamber 24b. It is recovered, and the remainder is discharged through the passage 58d.

As described above, in the stroke in which the pressure boosting piston 34 moves from the initial position to a predetermined distance in the A1 direction, the first pilot valve 72 is in the first position, and the pressure fluid from the supply port 40 is supplied to the fourth port 80D of the second pilot valve 74 through the first pilot valve 72. On the other hand, the second pilot valve 74 is in the second position, and no pressure fluid is supplied to the fourth port 76D of the first pilot valve 72 . Therefore, in the 1st pilot valve 72, the protrusion length of the knock pin 90-1 is pressed in the direction of decreasing, and the 1st pilot valve 72 is stably maintained in the 1st position. Moreover, in the 2nd pilot valve 74, the knock pin 90-2 is pressurized in the direction in which the protruding length increases, and the 2nd pilot valve 74 is stably maintained in the 2nd position.

And, as shown in FIG. 9, in the vicinity of the stroke end where the pressure boosting piston 34 displaces in the A1 direction, the second driving piston 38 moves the knock pin 90- of the second pilot valve 74. 2) touches The knock pin 90-2 is pushed by the second driving piston 38 to displace, and the first port 80A and the second port 80B of the second pilot valve 74 come into communication. Then, the pressure fluid from the supply port 40 passes through the second pilot passage 82b and is supplied to the pilot port 56F of the first operation valve 48, and passes through the branch passage 82c to remove pressure fluid. 1 is supplied to the fourth port 76D of the pilot valve 72. Thereby, while the 1st operation valve 48 switches to a 1st position, the 1st pilot valve 72 switches to a 2nd position.

When the first pilot valve 72 is switched to the second position, the pressure fluid supplied to the pilot port 64F of the second operation valve 52 passes through the first pilot oil passage 78b and the first pilot valve ( 72) is discharged from the third port 76C. By this, the second operation valve 52 is switched to the second position.

Further, when the first pilot valve 72 is switched to the second position, the pressure fluid supplied to the fourth port 80D of the second pilot valve 74 flows through the branch passage 78c and the first pilot passage 78b. ) and discharged from the third port 76C of the first pilot valve 72. For this reason, in the second pilot valve 74, the fluid pressure acts in the direction of reducing the protruding length of the knock pin 90-2. In this way, the knock pin 90-2 displaced until the first port 80A and the second port 80B of the second pilot valve 74 communicate with each other by the pressurization of the second driving piston 38. ) is held in a position in contact with the bottom surface of the valve receiving hole 84-2 while receiving further fluid pressure. That is, the second pilot valve 74 is stably maintained in the first position. The state in which the second pilot valve 74 is held in the first position is maintained until the first driving piston 36 is driven in the A2 direction to displace the knock pin 90-1, as will be described later. .

This time, part of the pressure fluid supplied from the supply port 40 passes through the flow path 58c, the first operating valve 48 in the first position and the flow path 58a, and the first driving cylinder 14 ) is supplied to the pressure chamber 24a. The first driving piston 36 is driven in the A2 direction by the pressure fluid supplied to the pressure chamber 24a. As a result, the pressure boosting piston 34 integrally connected to the first drive piston 36 slides, and the pressure fluid in the second pressure boosting chamber 22b of the pressure boosting cylinder 12 is increased. This increased pressure fluid passes through the second output flow passage 46b and the second output check valve 46d, is led to the output port 44, and is output.

On the other hand, when the second driving piston 38 integrally connected to the first driving piston 36 slides, the volume of the pressure chamber 26a of the second driving cylinder 16 decreases. Since the second operation valve 52 is in the second position, a part of the pressure fluid in the pressure chamber 26a passes through the flow path 66a, the flow path 66e, and the flow path 66b to the back pressure chamber 26b. It is recovered, and the remainder is discharged through the passage 66d.

Then, in the vicinity of the stroke end where the pressure boosting piston 34 displaces in the direction A2, the first driving piston 36 abuts against the knock pin 90-1 of the first pilot valve 72. The knock pin 90-1 is pushed by the first driving piston 36 to displace, and the first port 76A and the second port 76B of the first pilot valve 72 come into communication. Then, the pressure fluid from the supply port 40 passes through the first pilot passage 78b and is supplied to the pilot port 64F of the second operation valve 52, and passes through the branch passage 78c to remove pressure fluid. 2 is supplied to the fourth port 80D of the pilot valve 74. Thereby, while the 2nd operation valve 52 switches to a 1st position, the 2nd pilot valve 74 switches to a 2nd position.

When the second pilot valve 74 is switched to the second position, the pressure fluid supplied to the pilot port 56F of the first operation valve 48 passes through the second pilot oil passage 82b to allow the second pilot valve ( 74) is discharged from the third port 80C. With this, the first operating valve 48 is switched to the second position.

Further, when the second pilot valve 74 is switched to the second position, the pressure fluid supplied to the fourth port 76D of the first pilot valve 72 flows through the branch passage 82c and the second pilot passage 82b. ) and discharged from the third port 80C of the second pilot valve 74. For this reason, in the 1st pilot valve 72, the fluid pressure acts in the direction which reduces the protruding length of the knock pin 90-1. In this way, the knock pin 90-1 displaced until the first port 76A and the second port 76B of the first pilot valve 72 communicate with each other by the pressurization of the first driving piston 36 ) is maintained at a position in contact with the bottom surface of the valve receiving hole 84-1 while receiving further fluid pressure. That is, the first pilot valve 72 is stably maintained in the first position. The state in which the first pilot valve 72 is held in the first position is maintained until the second driving piston 38 is driven in the direction A1 again to displace the knock pin 90-2. Thereafter, the pressure boosting piston 34 repeats the reciprocating motion in the same manner, and the increased pressure fluid is continuously output from the output port 44 .

According to the pressure intensifying device 10 according to the present embodiment, the first port 76A and the second port 76B of the first pilot valve 72 communicate with each other by the pressurization of the first driving piston 36. The knock pin 90-1 displaced until it is displaced is then pushed in to a position in contact with the bottom surface of the valve receiving hole 84-1 by a predetermined fluid pressure, and can be held at that position. Similarly, the knock pin 90-2 displaced until the first port 80A and the second port 80B of the second pilot valve 74 communicate with each other by the pressurization of the second driving piston 38. Then, by a predetermined fluid pressure, it is pushed to a position where it comes into contact with the bottom surface of the valve accommodating hole 84-2, and can be held at that position.

In addition, the first operation valve 48 is switched to the first position when pilot pressure is supplied from the second pilot valve 74 whose position is switched in cooperation with the first pilot valve 72, and the second pilot valve ( When the pilot pressure is not supplied from 74), it is switched to the second position. Similarly, the second operation valve 52 is switched to the first position when pilot pressure is supplied from the first pilot valve 72 whose position is switched in cooperation with the second pilot valve 74, and the first pilot valve ( When the pilot pressure is not supplied from 72), it is switched to the second position. For this reason, the 1st operation valve 48 and the 2nd operation valve 52 operate stably, and switching is performed simultaneously.

Moreover, when driving the 1st driving piston 36, a part of the fluid supplied to the pressurization chamber 24a follows the 1st driving piston 36 along with the drive of the 2nd driving piston 38. Since it is recovered in the back pressure chamber 24b at the time of operation, the consumption of pressurized fluid can be reduced. Similarly, when driving the 2nd driving piston 38, a part of the fluid supplied to the pressurization chamber 26a drives the 2nd driving piston 38 along with the drive of the 1st driving piston 36. Since it is recovered in the back pressure chamber 26b at the time of operation, the consumption of pressurized fluid can be reduced.

The pressure intensifying device according to the present invention is not limited to the above-described embodiment, and it goes without saying that various configurations can be adopted within a range not departing from the gist of the present invention.

Claims (5)

A pressure intensifying device in which driving cylinders 14 and 16 are arranged on both sides of a pressure increasing cylinder 12,
A pair of pilot valves (72, 74) having knock pins (90) with which the pistons (36, 38) of the driving cylinder come into contact at their moving ends and pressurized chambers (24a, 26a) of the driving cylinder It includes a pair of operation valves 48 and 52 for switching the supply state of the pressure fluid from the pressure fluid supply source for the
When the piston presses the knock pin and the pilot valve on one side or the other side is switched to the first position, the state in which the pressure fluid is supplied to the pair of operation valves is switched, and the pilot valve is switched to the first position. A predetermined fluid pressure acts on the knock pin to hold it in position;
The position of the operating valve on the other side is switched depending on the presence or absence of pilot pressure supplied from the pilot valve on one side, and the operating valve on the one side is positioned depending on the presence or absence of pilot pressure supplied from the pilot valve on the other side. A pressure intensifier that converts delete The method of claim 1,
The pilot valve on one side has a supply port through which the pressure fluid is always supplied, and a cooperative port through which the pressure fluid is supplied through the pilot valve on the other side,
The pilot valve on the other side has a supply port through which the pressure fluid is always supplied, and a cooperation port through which the pressure fluid is supplied through the pilot valve on the one side,
The knock pin of the pilot valve on the one side or the other side is pressed in the direction in which the corresponding pilot valve becomes the second position when the pressure fluid is supplied to the cooperation port, and when the pressure fluid is not supplied to the cooperation port, the knock pin A pressure intensifier in which a predetermined fluid pressure acts. The method of claim 3,
When the pilot valve on the one side is in the first position, pilot pressure is supplied to the operation valve on the other side, and the pressure fluid is supplied to the cooperating port of the pilot valve on the other side, and the pilot valve on the other side is When in the first position, the pressure intensifier is supplied with the pilot pressure to the operation valve on the one side and the pressure fluid is supplied to the cooperating port of the pilot valve on the one side. The method of claim 1,
The operation valve is configured to supply the pressure fluid to the pressurization chamber of the driving cylinder and discharge the pressure fluid from the back pressure chambers 24b and 26b of the driving cylinder, and the pressure fluid in the pressurization chamber of the driving cylinder. A pressure intensifying device that is switched between a state in which a part of is returned to the back pressure chamber of the driving cylinder.

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