JPS624901A - Uniflow type boosting device - Google Patents

Abstract

PURPOSE:To prevent reduction of discharge quantity at a stroke end by changing, the direction of the stroke for one of two set of boosting pistons, when the other set of boosting pistons reaches the intermediate part of the stroke. CONSTITUTION:An boosting device is provided with two sets of boosting pistons, each set of which is provided with not only pistons 20 of large diameter on its both ends but also pistons 26 of small diameter projecting outward from said pistons 20 of large diameter. A housing 16, located nearly in the center of the range of a stroke for each piston 20 of large diameter, is provided with changeover means 46, 48 of a distributing changeover valve 32 changed over by means of the pistons of large diameter. When one set of pistons 20AR, 20AL of large diameter reaches the vicinity of the center of its stroke, a distributing changeover valve 32B for the other set of pistons 20BL, 20BR of large diameter is changed over, therefore, discharge quantity of the whole boosting device is not reduced even when the pistons 20AR, 20AL of large diameter reach the stroke end.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a pressure booster that is operated with a relatively low pressure liquid and supplies a higher pressure liquid to the outside, and particularly relates to a pressure increase device that is operated with a relatively low pressure liquid and supplies a higher pressure liquid to the outside. This invention relates to a pressure increase device that can continuously supply pressure.

BACKGROUND OF THE INVENTION The pressure increasing device as described above is disclosed in, for example, Japanese Utility Model Publication No. 59-2230.
This is already known from Publication No. 1 and the like.

In the pressure booster described in this publication, as shown in FIG.
A pair of small diameter pistons 106 are fixed to both ends of the large diameter screw I/N 104, and a large diameter piston 104 is fitted in the small diameter hole 108 in a liquid tight and sliding manner. possible to be mated. 2 11 & 1 hydraulic pressure chambers formed on both sides of the large-diameter piston 104]]0, a relatively low pressure liquid is switched by the switching valve 112,
They are supplied alternately. This switching valve 112
is a spool-type switching valve of the Pyritho 1 type, and the liquid to be supplied to the hydraulic pressure chamber 110 is supplied as pilot pressure via a spool-type on-off valve 116. The on-off valves 116 are opened when the large-diameter pistons 104 reach their respective stroke ends on both sides.
Further, the pilot pressure chambers 118 and 120 of the spool 114 of the switching valve z2 have different pressure receiving areas U. Furthermore, a suction valve 122 and a discharge valve 124 are provided for each small diameter hole 108, respectively.

Problems to be Solved by the Invention This pressure booster is designed to have the large diameter piston 104 reciprocate in short cycles, and in such cases it operates normally, but it does not work very well. If it reciprocates periodically or if the hydraulic pressure is maintained while it is almost stopped, there is a risk that it will not operate normally. For example, switching valve 1
In order to maintain the liquid pressure with the spool 114 of No. 12 in the position shown in Fig. 3, it is necessary to prevent the liquid trapped in the work chamber 120 from leaking. However, since it is impossible to completely eliminate such leakage in a spool-type valve, the spool 1
14 is slowly pylon I Royal 1. 20 side, and eventually the hydraulic fluid is not supplied to the hydraulic pressure chamber 110 on either side of the switching valve 112 or the large diameter piston 104, and the hydraulic pressure holding function is disabled. Enough is enough;
The cost of existence will be lost. A similar situation may also occur when the large-diameter piston 104 reciprocates over a long period of time, resulting in a temporary but significant drop in the output.

In addition, in such a reciprocating type pressure booster, it is inevitable that the discharge amount -) J < will drop momentarily at the pump of the large-diameter piston 104. However, since the switching valve 112 in this pressure booster is of a pilot type, a certain amount of liquid is consumed to switch the switching valve 112 at the end of the stroke of the large diameter piston 104, resulting in the above-mentioned drop in discharge volume. There is also the problem that this becomes even more pronounced.

If the switching valve 112 is replaced with an electromagnetic switching valve, the switching valve will switch instantaneously, so a pressure booster that operates almost normally even when maintaining hydraulic pressure as described above can be obtained, and a large-diameter piston can be used. Although the instantaneous drop in the discharge amount at the end of the stroke is also reduced, this may not be sufficient depending on the use of the pressure booster.

Means for Solving the Problems Against the background of the above, the present invention has been developed to provide a method that eliminates the risk of malfunction even when hydraulic pressure maintenance is required, and that is effective even at the slow end and low end of large diameter pistons. The purpose of this device is to provide a uniflow type pressure intensifier that does not reduce the discharge amount, and for this purpose, (a) each is fitted liquid-tightly and slidably into a large diameter hole, and is integrally formed with the other. (b) a large-diameter piston connected to the piston and receiving the pressure of the first liquid on pressure-receiving surfaces facing oppositely to each other, and (b) selectively applying the pressure of the first liquid to the pair of large-diameter pistons; (C) a switching valve that can be switched to act on the small-diameter hole; a pair of small-diameter pistons that move relative to each other; (d) a suction valve that allows the second liquid to flow into the small-diameter holes corresponding to each of the pair of small-diameter pistons, but not to allow it to flow out; and a suction valve that allows the second liquid to flow out but not to flow out. Two pressure intensifiers are provided, and a first liquid supply passage that separates and leads the first liquid from a common first liquid supply source is connected to the switching valve of each pressure intensifier. An inlet passage for guiding the second liquid is connected to the suction valve, and an outlet passage is connected to the discharge valve of each pressure intensifier for merging the second liquid discharged from the discharge valves and supplying the mixture to the outside. is provided with a switching means that is actuated by the large diameter piston or a member that moves integrally with the large diameter piston and switches the switching valve of the opposite pressure intensifier when each large diameter piston passes through the center of its reciprocating range. It is something that

Note that even if we say a pair of large-diameter pistons and a pair of small-diameter pistons, they are not necessarily two pairs in appearance.
It is not necessary that the pistons be separated into two parts (for example, even in the case of the large-diameter piston 104 of the pressure booster described in the above publication, it is assumed that a pair of large-diameter pistons are integrally formed. The small-diameter piston does not necessarily need to be fixed to the large-diameter piston as in the pressure intensifier described above, and it is also possible to fix the small-diameter piston to the housing side and provide the small-diameter hole on the large-diameter piston side.In this case, the small-diameter piston A liquid passage passing through the piston in the axial direction may be formed, and the second liquid may be supplied to and discharged from the small diameter hole through this liquid passage.Furthermore, the first liquid and the second liquid may be separated so that they do not mix with each other. It is also possible to use a series of products, or to use one system for both the first liquid and the second liquid.

Function: In the pressure booster configured as described above, two pressure boosters are operated by the continuously supplied first liquid, and the second liquid, which has a higher pressure than the first liquid, is supplied to the outside. . At that time, when the large-diameter piston of one pressure intensifier passes through the center of its reciprocating range, the switching valve of the other pressure intensifier is switched to change the direction of movement of the large-diameter piston of that pressure intensifier. It will be done. In other words, in the two pressure intensifiers, each large-diameter piston changes the direction of movement of the other large-diameter piston each time it passes through the center of its reciprocating range, and when one large-diameter piston reaches the end of its stroke, In this state, the other one is always moving in the center of the reciprocating range.

In this way, when the large-diameter piston of one pressure intensifier stops to change its direction of movement, the large-diameter piston of the other pressure intensifier is always moving, so that the flow of water discharged from that pressure intensifier is carried out from the outlet passage. Two liquids are supplied to the outside. Of course, the pressure intensifier on the side where the large-diameter piston has stopped will not discharge the second liquid, but the two pressure intensifiers are operated by the first liquid supplied from a common first liquid supply source. Because there is
When the large-diameter piston of one pressure intensifier stops, the large-diameter piston moves to the other pressure intensifier, and the first liquid that would normally be consumed in the pressure intensifier on the side where the large-diameter piston stopped is transferred to the other pressure intensifier. Since the pressure is supplied to the pressure intensifier on that side, the moving speed of the large diameter screw I/N of the pressure intensifier on that side increases and the discharge amount increases.
The decrease in the discharge amount of the second liquid due to the stoppage of one pressure intensifier is compensated for.

Effects of the Invention In the pressure booster according to the present invention, as described above, 2111
Since the pressure intensifier i1 compensates for the instantaneous drop in discharge volume at the stroke end of each large-diameter piston, the pressure booster as a whole can supply a constant discharge volume of the second liquid to the outside with almost no drop in discharge volume. becomes.

In addition, the two pressure intensifiers are configured to switch the switching valves of the other pressure booster to each other, so that when the switching valve of one pressure booster is switched, the switching valve of the other pressure booster must be completely switched. Therefore, even if the switching valve is switched slowly and the first liquid is not supplied to one pressure intensifier, there is a large diameter piston that is slowly switching the switching valve. Since the first liquid continues to be supplied to the pressure booster on the other side, there is no risk that the entire pressure booster will become inoperable, and the hydraulic pressure can be maintained reliably.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 shows a pressure booster which is an embodiment of the present invention, and this pressure booster includes two pressure boosters 10A,
IOB shares housing 12 with Nl1il.

The housing 12 includes a housing body 16 having two large-diameter holes 14A and 14B, and two covers 18 that are fixed to both end surfaces of the housing body 16 and close the openings at both ends of the large-diameter holes 14A and 14B. It consists of.

Inside the large diameter hole 14A, a pair of large diameter pistons 20AR, 20
The integrated AL is slidably fitted in a liquid-tight manner to form two hydraulic pressure chambers 22AL and 22AR.

In addition, 2 (hard cover 18 has small diameter holes 2/1A, respectively).
1. ．． 24 ARs are formed, each with a large i
Article Bis I/N 20.

20AI';! Small diameter piston 726Al fixed to
26AR is fluid-tightly and slidably fitted into the pressurizing chamber 28A.
L, 28AR are formed.

The liquid passages 30AL and 30AR are connected to the two hydraulic pressure chambers 22AL and 22AR, respectively, and these liquid passages are connected to the soil switching valve 32A, and the switching valve 32A is connected to the soil switching valve 32A.
1] path 3, connected to the liquid 1ffl path 35 by 1/lZ. There are 24 notches 33 on the spool of the switching valve 32A.
A is formed in the notch 33A, and by fitting a spring-loaded pawl (not shown) into these notches 33A, the spool can be stably maintained in any switching position.

Below-1-11 (9 The pressure intensifier 10A side has been explained, but since the pressure intensifier 10B side is similarly configured,
is replaced with B to indicate each component, and detailed explanation will be omitted. Also, A, B, 1. , , The symbol R is used when it is necessary to specifically indicate whether it is a component of
B asked, "When referring collectively to the constituent elements marked J and the constituent elements marked R or A/1, use the symbol without the R, and the constituent elements marked with an 8." When collectively referring to the constituent elements, use the symbol L; l: A, excluding rs.
I will do so.

Each of the above pressurized chambers 28△L, 28A[J has a suction valve 36
Liquid passage 38△L with AL and 36AR.

38AR is connected to the hydraulic chambers 22 A I-, 22A R, and the discharge valves 40AL and 40AR are connected to the
Engineering liquid communication u842 A 1. , 42 A R is connected to the Niyotte liquid jir circuit 44. The liquid passage il+835 is connected to a hydraulic pressure source such as a hydraulic pump, while the 11 passages 44 are connected to target devices such as actuators that require higher hydraulic pressure than the hydraulic pressure source. In other words, the liquid passages 35 and 34 constitute a first liquid supply passage that divides the first liquid supplied from a common hydraulic pressure source to the two pressure intensifiers 10, and A portion of the passage 42 functions as an outlet passage for merging the second liquid discharged from the pressurizing chamber 28 of the Ryogawa pressure device 10 and supplying it to the outside. The 3 m inlet path is constituted by a portion connecting each hydraulic pressure chamber 22 of the liquid passage 38 and the suction valve 36, and in this embodiment, the first liquid supplied to the hydraulic pressure chamber 22 of It is also used as a two-component product.

The large-diameter piston 20A is provided with a flange 16A, which engages with the switching lever 488 when the large-diameter piston 20A passes through the middle position of its reciprocating range and pivots it. Rotated around 50A-
By switching the switch valve 32B, the switching valve 32B is switched. The same goes for the pressure intensifier 10B side, when the large diameter piston 20B passes through the middle position of its reciprocating range, the flange 46B and the switching lever 48B
The switching valve 32A can be switched via the switch. That is, the flanges 46A, 46B and the switching lever 4
When the large diameter piston 20 of one pressure intensifier 10 passes through the center position of the reciprocating range due to 8Δ and 48B,
A switching means for switching the switching valve 32 of the pressure booster 10 on the other side is configured.

Next, the operation will be explained.

In the state shown in FIG. 1, the switching valve 32A is switched to the left-hand state, and the --on switching valve 32B is switched to the right-hand state. Therefore, the first liquid supplied to the liquid passage 35 is in the hydraulic pressure chamber 22A on the pressure intensifier 10A side.
R, and on the pressure intensifier 10B side, the hydraulic pressure chamber 22B
(J) is supplied to (J). Therefore, in the state shown in Figure The large diameter piston 20B is exactly on the left side.
The low end is about to be reached, and the flange 46A on the pressure intensifier 10A side engages with the switching lever 48A, and the switching valve 32B is about to be switched.

In this state where both the large diameter pistons 2OA and 20B move to the left, the hydraulic pressure chamber 22AL.

The volume of 22BL decreases, and the first l1shi inside these becomes 11browIIJf7h30△1. ,．． Is it refluxed to the tank via 30B+-? ! 1, pressurized chamber 21'1Al-.

The volume fIli4) of 28th Street 7 decreases, and the second liquid inside them is supplied to the outside from the liquid passage 44 via the discharge valves 40A+= and 40BL. The pressure of the second liquid supplied to the outside is increased by increasing the pressure of the first liquid supplied from the 1&1ffl passage 35 by increasing the area between the human piston 20 and the small diameter screw 26. Become.

When the large diameter piston 2OA moves a short distance to the left from the state shown in FIG. 1, the switching lever 48A is rotated by the flange 46A, and the switching valve 32B is switched to the left state. Therefore, on the pressure intensifier 10B side, the first liquid supplied from the liquid passage 35 flows into the liquid pressure chamber 22B+- via the liquid passage 30BL, and the first liquid in the liquid pressure chamber 22BR flows through the liquid passage 30BR. After that, the tank becomes refluxed,
The direction of movement of the large diameter piston 20B is reversed. At this time, although for a short time, the switching valve 32B is switched to either hydraulic pressure chamber 22131. on the pressure intensifier 10B side. , , 22 +3 R is also not supplied with the first liquid, the large diameter piston 20 +3 is stopped, and the pressure intensifier 1OB is in a state where it does not discharge the second liquid. However, in this state, the first liquid is no longer consumed on the pressure intensifier 10B side, so the first liquid flows into the hydraulic pressure chamber 22AR of the pressure intensifier 10A, and the moving speed of the large diameter piston 2OA is doubled. Therefore, the discharge amount of the second liquid from the pressurizing chamber 28L is doubled, which compensates for the shortage of discharge M due to the stoppage of the pressure intensifier 10B, and the discharge amount of the pressure intensifier as a whole remains unchanged. .

When the large-diameter histone 20A that has switched the switching valve 32B as described above moves further to the left and reaches the vicinity of the left stroke end, the large-diameter piston 20B reaches the middle position of the reciprocating range and the flange 46B engages the switching lever 48B and switches the switching valve 32A. Thereafter, the same process is repeated and the second liquid is continuously supplied to the outside from the liquid passage 44.

It is clear that the above operation is performed without any problem even when the large-diameter piston 20 moves extremely slowly, and this pressure increase device can perform the pressure increase function without any problem even when almost no second liquid flows out from the liquid passage 44. It is also possible to maintain hydraulic pressure.

FIG. 2 shows another embodiment of the invention. In this pressure booster, the switching valves are electromagnetic switching valves 60A and 60B, and the flanges 46A and 46B and the switching lever 48
Annular grooves 62A, 62B and limit switch 64A in place of A, 48B.

64B is provided. That is, when each of the large-diameter screws 1 to 20 passes through the middle position of the reciprocating range, the screws 1 to switches 64A and 64B are switched, and the electromagnetic switching valve 60A is activated based on the electric signal.

60B, these annular grooves 62A, 62B, limit switch 64
A, 64B, etc. constitute the switching means of the switching valve. In other respects, this embodiment is similar to the embodiment described above, so corresponding parts are denoted by the same reference numerals to indicate correspondence, and detailed explanation will be omitted.

In FIG. 2, limit switch 64A is in an on state, and limit switch 64B is in an off state. Therefore, the electromagnetic switching valve 60A is in the right-hand state, the electromagnetic switching valve 60B is in the left-hand state, and both the large diameter pistons 2OA and 20B4J are moving to the left as shown by the arrows. The large-diameter piston 2'OB is located just before reaching the left stroke end, and the large-diameter piston 20A is located approximately at the center of the reciprocating range. From this state, the large diameter piston 2OA moves slightly to the left, the mint switch 64A is switched from the on state to the off state, the switching valve 60A is switched to the left state, and the moving direction of the large diameter piston 20B is changed. be reversed. That is, the pressure increase device of this embodiment operates in substantially the same manner as the pressure increase device of the previous embodiment, and can continuously supply a constant flow rate of the second liquid to the outside from the liquid passage 44.

1 and 2, a part of the liquid passage is shown as being formed inside the housing 12 and the remaining part is provided outside the housing, but most of the liquid passage is formed inside the housing 12. Furthermore, it is also possible to form the housing of the switching valve 32 integrally with the housing of the pressure intensifier 10. Conversely, the pressure booster is 10A.

It is also possible to make the housing of 10B separate, or to configure most of the liquid passages by external piping or manifolds.

Although not illustrated individually, it goes without saying that the present invention can be implemented with various modifications and improvements based on the knowledge of those skilled in the art.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a pressure booster that is an embodiment of the present invention, and is also a front sectional view of a pressure booster that is the main part thereof. FIG. 2 is a diagram corresponding to FIG. 1 showing another embodiment of the present invention. FIG. 3 is a circuit diagram showing an example of a conventional pressure booster, and is also a front sectional view of its main parts. ■OA, IOB: Pressure booster 12; Housing 14A, 1
4. B: Large diameter holes 20AL, 20AR, 20BL, 20BR: Large diameter pistons 22AL, 22AR, 22BL, 22BR: Hydraulic pressure chambers 24AL, 24AR, 24BL, 24BR: Small diameter holes 26AL, 26AR, 26BL, 26BR: Small diameter pistons 28AL, 28AR , 28BL, 28BR: Pressurized chambers 32A, 32B: Switching valves 36AL, 36AR, 36BL, 36BR: Suction valves 38AL, 38AR, 38BL, 38BR: Liquid passage (inlet passage) 40AL, 4.0AR, 40BL, 40BR: Discharge valve 60A, 60B: Solenoid switching valve

Claims (1)

[Claims] a pair of large-diameter pistons that are fluid-tightly and slidably fitted into large-diameter holes, are integrally connected to each other, and receive the pressure of the first liquid on pressure-receiving surfaces facing oppositely to each other; a switching valve that can be switched to selectively apply the pressure of the first liquid to the pair of large diameter pistons; a pair of small-diameter pistons that move relative to the small-diameter holes as the pistons move; a suction valve that allows the second liquid to flow into the small-diameter holes corresponding to the pair of small-diameter pistons, but does not allow the second liquid to flow out; Two pressure intensifiers each having a discharge valve that allows outflow but not inflow are provided, and a first liquid supply is provided in which the first liquid from a common first liquid supply source is separately guided to the switching valve of each pressure intensifier. connecting the passages, connecting an inlet passage for guiding the second liquid to the suction valve of each pressure intensifier, and further connecting the second liquid discharged from the discharge valves to the discharge valve of each pressure intensifier and supplying it to the outside. At the same time, each pressure intensifier is actuated by the large diameter piston or a member that moves together with the large diameter piston when the large diameter piston passes through the center of its reciprocating range. A uniflow pressure booster, characterized in that the pressure booster includes a switching means for switching the switching valve of the pressure booster.