WO2007117099A1

WO2007117099A1 - Hydraulic pressure transformers

Info

Publication number: WO2007117099A1
Application number: PCT/KR2007/001698
Authority: WO
Inventors: Young-Don Ju; Jin-Young Joo; Da-Young Ju
Original assignee: Jung-A Hydraulic Co., Ltd.
Priority date: 2006-04-12
Filing date: 2007-04-06
Publication date: 2007-10-18
Also published as: KR100704958B1; CN101421522A

Abstract

The present invention relates to a hydraulic pressure intensifier that has all of the advantages of the pneumatic cylinder and the hydraulic cylinder and includes first operating chambers, a hydraulic operating chamber, front and back operating chambers, and second operating chambers formed sequentially from the front side thereof. The front and back operating chambers and the hydraulic operating chambers are connected through an excess flow bore, and an operating rod is moved forwardly by the supply of the air pressure to the first operating chambers and the front and back operating chambers. Then, only upon the application of a high load the air pressure is selectively supplied to the second forwardly moving operating chamber through a pilot valve and a master valve, thereby generating a high pressure in the hydraulic operating chamber.

Description

HYDRAULIC PRESSURE TRANSFORMERS

Technical Field

[1] The present invention relates to a hydraulic pressure intensifier, and more particularly, to a hydraulic pressure intensifier that is capable of improving the performance and output of a pneumatic cylinder as widely utilized in all kinds of industrial fields. Background Art

[2] Pneumatic cylinders and hydraulic cylinders are mainly used for applying a pressurizing force, and therefore, they are adopted in clamp devices, compression devices, cocking devices, and the like. The clamp devices or compression devices does not need an operating force at the time of starting an operation, but need a relatively large operating force at the time of finishing the operation. Thus, the cylinders that are used for applying a given pressurizing force should provide a much larger operating force at the end portion of extruding a piston rod.

[3] For this reason, the cylinder having an unnecessarily large diameter and weight should be adopted so as to obtain the necessary large operating force at the end portion of extruding the piston rod. In case where such the cylinder having the substantially large diameter and weight is used, however, the operating speed is relatively slow, thereby reducing the working efficiency, and a large quantity of air pressure or hydraulic oil is needed, thereby causing the loss of energy and the increased consumption of costs.

[4] To address and solve these problems, there has been proposed a conventional cylinder where a booster is connected to a pipeline that supplies oil pressure or air pressure to the cylinder so as to apply a substantially high pressure at the end portion of extruding the piston rod, thereby increasing the operating force at the end portion of the piston rod.

[5] However, since it is required that the conventional cylinder should have a relatively complex structure and includes four or more electronic valves, a variable pump, and a control unit, it becomes expensive and has high failure rates.

Disclosure of Invention

Technical Problem

[6] Accordingly, the present invention has been made in an effort to solve the problems occurring in the conventional hydraulic pressure intensifier, and it is an object of the present invention to provide a hydraulic pressure intensifier that has high output despite its small size, has high energy efficiency, and has a simplified configuration, and that conduct an intensifying operation and a backwardly moving operation in more rapid and accurate manners, thereby enhancing the precision of the operations and preventing the generation of malfunctions. Technical Solution

[7] To achieve the above object, according the present invention, there is provided a hydraulic pressure intensifier including: first operating chambers having a backwardly moving air pressure passageway formed at the front side thereof and a forwardly moving air pressure passageway formed at the rear side thereof and having an operating piston disposed therein, the operating piston having an operating rod protruded outwardly therefrom; a hydraulic operating chamber having a guide rod formed at the rear side of the operating piston disposed therein; operating chambers having a piston disposed around the inner peripheries thereof and connected at the front side thereof to the rear side of the hydraulic operating chamber to form oil pressure, the piston having a forwardly moving air pressure passageway formed at the rear side thereof; second operating chambers having a pressure-intensifying piston disposed therein, the pressure-intensifying piston having a pressure-intensifying rod adapted to pass through the piston for moving forwardly and backwardly inside the hydraulic operating chamber and a spring disposed around the outer periphery thereof, the second operating chambers having an air pressure passageway formed at the front side thereof and a forwardly moving air pressure passageway formed at the rear side thereof; and a master valve connected to the forwardly moving air pressure passageway of the second operating chambers and sequentially partitioned by means of a spool pin disposed therein into a forwardly moving operating chamber having a forwardly moving air pressure inlet formed thereon, a backwardly moving discharging chamber having a backwardly moving air pressure outlet formed thereon, a backwardly moving operating chamber having an internal air pressure passageway formed at the front side thereof, and an intensifying operating chamber connected to a pilot valve or a check valve disposed at the backwardly moving air pressure passageway, such that the spool pin is moved backwardly to block the forwardly moving air pressure passageway at the initial forward movement of the operating rod, the oil pressure of the forwardly moving operating chamber is higher than the intensifying operating chamber to move the spool pin forwardly at the application of a high load, thereby sending the oil pressure to the forwardly moving air pressure passageway, and the spool pin returns to the original position thereof at the backward movement of the operating rod.

[8] On the other hand, the master valve and the pilot valve or the check valve are formed integrally or separately with/from a hydraulic pressure intensifier body. [9] Further, the piston has a check valve adapted to prevent the air pressure at the rear side thereof from being supplied to the front side thereof and a sealing ring adapted to seal the oil supplied thereto.

Advantageous Effects

[10] According to the present invention, there is provided a hydraulic pressure intensifier that does not conduct the intensifying operation upon the application of a low load, but conducts the intensifying operation upon the application of a high load, thereby reducing the quantity of air consumed and minimizing the operating time.

Brief Description of the Drawings

[11] FIG.1 is a longitudinal sectional view showing a configuration of a master valve- embedded hydraulic pressure intensifier according to a first embodiment of the present invention; [12] FIG.2 is a longitudinal sectional view showing the backward moving state of the hydraulic pressure intensifier according to the first embodiment of the present invention; [13] FIG.3 is a longitudinal sectional view showing the low load state upon the forward movement operation of the hydraulic pressure intensifier according to the first embodiment of the present invention; [14] FIG.4 is a longitudinal sectional view showing the high load state of the hydraulic pressure intensifier according to the first embodiment of the present invention; [15] FIG.5 is a longitudinal sectional view showing the backward moving state of a pilot valve constituting the hydraulic pressure intensifier according to the first embodiment of the present invention; [16] FIG.6 is a longitudinal sectional view showing the low load state upon the forward moving operation of the pilot valve of the hydraulic pressure intensifier according to the first embodiment of the present invention; [17] FIG.7 is a longitudinal sectional view showing the high load state upon the forward moving operation of the pilot valve of the hydraulic pressure intensifier according to the first embodiment of the present invention; [18] FIG.8 is a longitudinal sectional view showing a configuration of a hydraulic pressure intensifier according to a second embodiment of the present invention wherein a check valve is connected in place of the pilot valve; [19] FIG.9 is a longitudinal sectional view showing a configuration of a hydraulic pressure intensifier according to a third embodiment of the present invention wherein an external master valve is provided at a state of being coupling with the pilot valve; and [20] FIG.10 is a longitudinal sectional view showing a configuration of a hydraulic pressure intensifier according to a fourth embodiment of the present invention wherein an external master valve is provided at a state of being coupling with the check valve.

[21]

[22] * Explanation on the reference numerals on the main parts in the drawings *

[23] 1: body 10a, 10b: first operating chamber

[24] 11: operating rod 13: operating piston

[25] 20: hydraulic operating chamber 21: guide rod

[26] 23: excess flow bore 30a,30b: operating chamber

[27] 33: piston 40a, 40b: second operating chamber

[28] 41: pressure-intensifying rod 42: spring

[29] 43: pressure-intensifying piston

[30] 46: forwardly moving air pressure passageway

[31] 60: master valve 62: spool pin

[32] 70: pilot valve 71 : operating pin

Mode for the Invention

[33] Hereinafter, an explanation on a preferred embodiment of the present invention will be in detail given with reference to the attaching drawings.

[34] FIGS.1 to 7 show a master valve-embedded hydraulic pressure intensifier according to a first embodiment of the present invention.

[35] According to the first embodiment of the present invention, as shown in FIGS.1 to

4, the hydraulic pressure intensifier includes: first operating chambers 10a and 10b having an operating piston 13 disposed therein; a hydraulic operating chamber 20 having a guide rod 21 disposed therein; operating chambers 30a and 30b having a piston 33 disposed around the inner peripheries thereof and connected to the rear side of the hydraulic operating chamber 20; second operating chambers 40a and 40b having a pressure-intensifying piston 43 disposed therein, the pressure-intensifying piston 43 having a pressure-intensifying rod 41 adapted to pass through the piston 33 for moving forwardly and backwardly inside the hydraulic operating chamber 20 and a spring 42 disposed around the outer periphery thereof; a master valve 60 disposed at the rear side of the second operating chamber 40a (hereinafter, referred to as a second forwardly moving operating chamber) formed on the rear portion of the pressure-intensifying piston 43 for controlling the flow of the air pressure supplied and discharged to and from the second forwardly moving operating chamber 40a; and a pilot valve 70 mounted at the master valve 60 for controlling the master valve 60.

[36] First, the first operating chambers 10a and 10b are formed at the front side of the body 1 and have the operating piston 13 disposed therein, the operating piston 13 having an operating rod 11 protruded outwardly toward the front side thereof and a guide rod 21 protruded backwardly toward the inside of the hydraulic operating chamber 20. The formation of the operating piston 13 makes the first operating chamber 10b defined as a first backwardly moving operating chamber 10b and makes the first operating chamber 10a defined as a first forwardly moving operating chamber 10a. Thus, at the front side of the first backwardly moving operating chamber 10b is provided a backwardly moving air pressure passageway 15, and at the rear side of the first forwardly moving operating chamber 10a is provided a forwardly moving air pressure passageway 17.

[37] Further, the hydraulic operating chamber 20 has the guide rod 21 disposed therein and is connected to the front operating chamber 30a through an excess flow bore 23 disposed at the rear side thereof, for preventing the hydraulic oil in the front operating chamber 30a from lacking upon the generation of intensified pressure.

[38] The operating chambers 30a and 30b are connected to the hydraulic operating chamber 20 at the front side thereof and have a forwardly moving air pressure passageway 35. The formation of the piston 33 makes the operating chamber 30a the front operating chamber and makes the operating chamber 30b the rear operating chamber.

[39] On the other hand, the piston 33 has an oil invasion-preventing chamber 38 so as to prevent the air pressure in the rear operating chamber 30b from flowing to the front operating chamber 30a, the oil invasion-preventing chamber 38 having a check valve 36 disposed at a portion connected to the front operating chamber 30b and a sealing ring 37 disposed at the both sides thereof in such a manner as to maintain the air tightness therein.

[40] The operating chambers 40a and 40b are formed at the rear side of the body 1, and the pressure-intensifying rod 41 is passed through the piston 33 to move forwardly and backwardly inside the hydraulic operating chamber 20, such that the oil pressure is intensified or released. The formation of the pressure-intensifying piston 43 having the spring 42 disposed around the outer periphery thereof makes the front operating chamber 40b defined as a second backwardly moving operating chamber 40b and makes the rear operating chamber 40a defined as a second forwardly moving operating chamber 40a. Thus, at the front side of the second backwardly moving operating chamber 40b is provided an air passageway 44, and at the rear side of the second forwardly moving operating chamber 40a is provided a forwardly moving air pressure passageway 46 connected to the master valve 60.

[41] Further, the second forwardly moving operating chamber 40a is connected at the rear side thereof to the master valve 60 adapted to be controlled by means of the pilot valve 70. The master valve 60 connects a forwardly moving air pressure inlet 61a and the forwardly moving air pressure passageway 46 upon the application of a high load during the forward movement and discharges the air pressure supplied to the second forwardly moving operating chamber 40a through a backwardly moving air pressure outlet 61b during the backward movement.

[42] As shown in FIGS.5 to 7, the master valve 60 is sequentially partitioned by means of a spool pin 62 disposed therein into a forwardly moving operating chamber 63 having a forwardly moving air pressure supplied separately thereto, a backwardly moving discharging chamber 64 having the air pressure discharged during the backward movement from the second forwardly moving operating chamber 40a passed therethrough, a backwardly moving operating chamber 65 having an internal air pressure passageway 65a formed at the front side thereof for flowing a backwardly moving air pressure thereto, and an intensifying operating chamber 68 connected to the pilot valve 70 disposed at the backwardly moving air pressure passageway 66. The spool pin 62 has a plurality of packing members 62a disposed along the outer periphery thereof in such a manner as to come into close contact with the inner wall of the master valve 60 for sealing each operating chamber.

[43] Referring to the operation of the master valve 60 as mentioned above, during the backward movement the air pressure supplied through the pilot valve 70 is sent to the intensifying operating chamber 68 and the backwardly moving operating chamber 65 through the internal air pressure passageways 65a and 69, thereby moving the spool pin 62, such that the forwardly moving air pressure passageway 46 and the backwardly moving air pressure outlet 61b are connected with each other.

[44] Then, upon the application of a low load during the forward movement the air pressure remaining in the backwardly moving operating chamber 65 is slowly discharged to the backwardly moving air pressure passageway 66 through the internal air pressure passageway 65a, and if the air pressure supplied to the forwardly moving air pressure inlet 61a is increased to make the air pressure in the forwardly moving operating chamber 63 having a smaller sectional area than the intensifying operating chamber 68 near the air pressure in the intensifying operating chamber 68, the spool pin 62 is moved in an opposite direction thereto, such that the forwardly moving air pressure inlet 61a communicates with the forwardly moving air pressure passageway 46. Thus, the forwardly moving air pressure flows into the second forwardly moving operating chamber 40a to move the pressure-intensifying piston 43 forwardly, thereby allowing the excess flow bore 23 to be blocked to conduct the intensifying operation in the hydraulic operating chamber 20.

[45] The pilot valve 70 has a valve piston 73 disposed at one side of the inside of a valve-operating chamber 74 thereof, a packing member 72 disposed at the other side of the inside of the valve-operating chamber so as to come into close contact with or to be separated from the internal inclined surface of the valve-operating chamber 74 for keeping or releasing air tightness therein, an operating pin 71 having a spring 75 disposed along the outer periphery of the rear portion of the packing member 72 thereof, for allowing the packing member 72 to open and close the space between the backwardly moving air pressure passageway 66 and the internal air pressure passageway 69, the pilot valve 70 being connected at the both sides to the internal air pressure passageway 69 communicating with the intensifying operating chamber 68 and to the internal air pressure passageway 65a communicating with the backwardly moving operating chamber 65 of the master valve 60.

[46] Moreover, the forwardly moving air pressure passageway 35 is connected to forwardly moving air pressure-generating means, and the backwardly moving air pressure passageway 15 is to backwardly moving air pressure-generating means.

[47] Under the above configuration, an explanation of the operation of the hydraulic pressure intensifier according to the present invention will be given below.

[48] Referring first to the backward movement, an air pressure is supplied to the first backwardly moving operating chamber 10b through the backwardly moving air pressure passageway 15, thereby moving the operating piston 13 backwardly, and at the same time, the air pressure is supplied to the backwardly moving air pressure passageway 66 of the pilot valve 70, thereby pushing the valve piston 73 and the operating pin 71 of the valve-operating chamber 74. As a result, the air pressure is sent to the intensifying operating chamber 68 and the backwardly moving operating chamber 65 through the backwardly moving air pressure passageway 66 and the internal air pressure passageways 69 and 65a, thereby pushing the spool pin 62 downwardly, such that the forwardly moving air pressure passageway 46 and the backwardly moving air pressure outlet 61b communicate with each other, thereby discharging the air pressure from the second backwardly moving operating chamber 40a. At this time, the pressure-intensifying piston 43 is moved backwardly by means of the spring 42 and becomes at the state as shown in FIGS.2 and 5.

[49] Next, an explanation of the forward movement of the hydraulic pressure intensifier according to the present invention will be given.

[50] If the forwardly moving air pressure is supplied through the forwardly moving air pressure passageway 35 formed in the middle portion of the body 1 at the state as shown in FIG.2, the air pressure is first sent to the forwardly moving operating chamber 30b, thereby moving the piston 33 forwardly, and is then sent through the forwardly moving air pressure passageway 17 to the first forwardly moving operating chamber 10a, thereby moving the operating piston 13 forwardly.

[51] At this time, since the backwardly moving air pressure is not supplied anymore, the air pressures in the valve-operating chamber 74 of the pilot valve 70 and the backwardly moving operating chamber 65 of the master valve 60 are discharged through the backwardly moving air pressure passageway 66, such that the operating pin 71 is moved by means of the spring 75 to allow the packing member 72 to come into close contact with the body of the pilot valve 70, thereby blocking the backwardly moving air pressure passageway 66 and the internal air pressure passageway 69.

[52] As a result, the air pressure caught in the intensifying operating chamber 68 is sent to the front side of the spool pin 62, such that even though the forwardly moving air pressure is sent to the forwardly moving operating chamber 63 through the forwardly moving air pressure inlet 61a, the spool pin 62 is not moved at all, as shown in FIG.6.

[53] Therefore, the forwardly moving air pressure inlet 61a and the forwardly moving air pressure passageway 46 are blocked such that the air pressure is not sent to the second forwardly moving operating chamber 40a, which makes the pressure-intensifying piston 43 kept at a halting state, as shown in FIG.3.

[54] After that, the operating piston 13 moves forwardly, and if the operating rod 11 abuts at the front end portion thereof with an object to be worked and does not stand the load, the operating piston 13 halts and the piston 33 also halts, such that the air pressures in the first forwardly moving operating chamber 10a and the rear operating chamber 30b are continuously raised and at the same time the air pressure in the forwardly moving operating chamber 63 of the master valve 60 is raised.

[55] If the air pressure in the forwardly moving operating chamber 63 is raised near the air pressure in the intensifying operating chamber 68, the sectional area of the forwardly moving operating chamber 63 is somewhat larger than that of the intensifying operating chamber 68, such that the spool pin 62 is moved. Thus, the air pressure in the intensifying operating chamber 68 is discharged through the backwardly moving operating chamber 65 to the backwardly moving air pressure passageway 66, and the spool pin 62 is raised up to the rising end thereof.

[56] As shown in FIG.7, therefore, the forwardly moving air pressure inlet 61a and the forwardly moving air pressure passageway 46 communicate with each other, and the forwardly moving air pressure is sent to the second forwardly moving operating chamber 40a, such that the pressure-intensifying rod 41 is passed through the excess flow bore 23, and at the same time, the oil pressure of the hydraulic operating chamber 20 is raised to apply a substantially large force to the front end portion of the operating rod 11.

[57] On the other hand, FIG.8 shows the hydraulic pressure intensifier according to a second embodiment of the present invention, wherein the master valve 60 is formed integrally with the body 1, and in place of the pilot valve, a check valve 76 is connected as a separate part from the body 1 with the intensifying operating chamber 68 of the master valve 60. Further, the internal air pressure passageway 65a connected with the backwardly moving operating chamber 65 is connected to the rear end of the check valve 76. In this case, the operations in the second embodiment of the present invention are the same as in the first embodiment of the present invention, and an explanation on them will be avoided for the brevity of this invention.

[58] FIG.9 shows the hydraulic pressure intensifier according to a third embodiment of the present invention, wherein the master valve 60 and the pilot valve 70 are formed separately from the body 1, and a reference numeral 45 denotes a forwardly moving air pressure passageway connected to the forwardly moving air pressure passageway 46 connected with the second forwardly moving operating chamber 40a.

[59] FIG.10 shows the hydraulic pressure intensifier according to a fourth embodiment of the present invention, wherein the master valve 60 and the check valve 76 are formed separately from the body 1.

Claims

[ 1 ] A hydraulic pressure intensifier comprising: first operating chambers having a backwardly moving air pressure passageway formed at the front side thereof and a forwardly moving air pressure passageway formed at the rear side thereof and having an operating piston disposed therein, the operating piston having an operating rod protruded outwardly therefrom; a hydraulic operating chamber having a guide rod formed at the rear side of the operating piston disposed therein; operating chambers having a piston disposed around the inner peripheries thereof and connected at the front side thereof to the rear side of the hydraulic operating chamber to form oil pressure, the piston having a forwardly moving air pressure passageway formed at the rear side thereof; second operating chambers having a pressure-intensifying piston disposed therein, the pressure-intensifying piston having a pressure-intensifying rod adapted to pass through the piston for moving forwardly and backwardly inside the hydraulic operating chamber and a spring disposed around the outer periphery thereof, the second operating chambers having an air pressure passageway formed at the front side thereof and a forwardly moving air pressure passageway formed at the rear side thereof; and a master valve connected to the forwardly moving air pressure passageway of the second operating chambers and having a spool pin disposed therein, the spool pin adapted to be controlled by means of a pilot valve or a check valve, such that at the initial forward movement of the operating rod, the pilot valve or check valve is closed and the spool pin blocks the forwardly moving air pressure passageway by means of an internal air pressure, and upon the application of a high load during a forward movement, the internal air pressure is discharged to cause the spool pin to open the forwardly moving air pressure passageway to send a forwardly moving air pressure to the second operating chambers, thereby generating the intensified pressure.

[2] The hydraulic pressure intensifier according to claim 1, wherein the master valve is sequentially partitioned by means of a spool pin disposed therein and a plurality of packing members formed along the outer periphery of the spool pin into a forwardly moving operating chamber having a forwardly moving air pressure inlet formed thereon, a backwardly moving discharging chamber having a backwardly moving air pressure outlet formed thereon, a backwardly moving operating chamber having a first internal air pressure passageway formed at the front side thereof, the first internal air pressure passageway connected with a backwardly moving air pressure passageway, and an intensifying operating chamber connected to the pilot valve or the check valve disposed at the backwardly moving air pressure passageway and having a smaller size than that of the forwardly moving operating chamber, such that the spool pin is moved backwardly to block the forwardly moving air pressure passageway at the initial forward movement of the operating rod, the oil pressure of the forwardly moving operating chamber is higher than the intensifying operating chamber to move the spool pin forwardly upon the application of a high load, thereby discharging the oil pressure from the intensifying operating chamber to the first internal air pressure passageway through the backwardly moving operating chamber and connecting the forwardly moving air pressure passageway and the forwardly moving air pressure inlet, and the backwardly moving oil pressure is sent to the backwardly moving operating chamber at the backward movement of the operating rod, thereby returning the spool pin to the original position thereof.

[3] The hydraulic pressure intensifier according to claim 2, wherein the pilot valve connected to the master valve has a valve piston disposed at one side of the inside of a valve-operating chamber thereof, a packing member disposed at the other side of the inside of the valve-operating chamber so as to come into close contact with or to be separated from the internal inclined surface of the valve- operating chamber for connecting or blocking the backwardly moving air pressure passageway and the intensifying operating chamber, and an operating pin having a spring disposed along the outer periphery of the rear portion of the packing member, the pilot valve being connected at the both sides to a second internal air pressure passageway communicating with the intensifying operating chamber of the master valve and to the first internal air pressure passageway of the backwardly moving operating chamber.

[4] The hydraulic pressure intensifier according to claim 1 or 2, wherein the intensifying operating chamber of the master valve is connected to a check valve, and the first internal air pressure passageway connected with the backwardly moving operating chamber is connected to the rear end of the check valve.

[5] The hydraulic pressure intensifier according to claim 1 or 2, wherein the master valve and the pilot valve or the check valve are formed integrally or separately with/from a hydraulic pressure intensifier body.

[6] The hydraulic pressure intensifier according to claim 1, wherein the hydraulic operating chamber has an excess flow bore disposed at the rear side thereof, for preventing hydraulic oil in the front operating chamber from lacking upon the generation of a high load.

[7] The hydraulic pressure intensifier according to claim 1, wherein the piston comprises an oil invasion-preventing chamber formed of a check valve and a sealing ring.