JP2002339914A - Reciprocating piston device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reciprocating piston device having superior practicality and generality and capable of arbitrarily providing the maximum generated load and the maximum generated speed exhibited by a piston by arbitrarily setting a pressure receiving area of a pressure receiving part of the piston. SOLUTION: This reciprocating piston device is provided with a cylinder 1, the piston 3 slidably fitted in a cylinder hole 2 in the cylinder 1, and a fluid extraction/injection device 4 extracting/injecting the fluid from/into the cylinder hole 2 so as to reciprocate the piston 3. The cylinder 1 is provided with two or more divided cylinder holes 2a and 2b, the piston 3 is penetrated through the respective divided cylinder holes 2a and 2b and provided with two or more pressure receiving parts 5a and 5b receiving the hydraulic pressure. The two or more pressure receiving parts 5a and 5b are disposed in the respective divided cylinder holes 2a and 2b, and the fluid extraction/injection device 4 is provided with a changeover device 6 extracting/injecting the fluid from/in an arbitrary hole of the divided cylinder holes 2a and 2b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating piston device.

[0002]

2. Description of the Related Art A reciprocating piston device in which a piston reciprocates by hydraulic control has been proposed as a servo actuator of a vibration test device.

FIG. 1 shows a conventional example of this reciprocating piston device.

In this conventional example, a cylinder 31 and the cylinder 31
Pressure receiving part 35 slidably fitted in cylinder hole 32 in 31
A pump 33 and a servo valve 36 for pouring oil into and out of the cylinder hole 32 to reciprocate the piston 33, and by switching the servo valve 36 while driving the pump 34, The piston 33 is caused to reciprocate by arbitrarily pouring oil into and out of the cylinder hole 32 and alternately pressurizing the pressure receiving portion 35 from the left and right (actually, the difference between the left and right of the pressure receiving portion 35). The pressure is applied by pressure.)

The conventional example has the following problems.

The maximum generated load (Fmax) and the maximum generated speed (Vmax) when the piston 33 reciprocates are determined by the pressure receiving portion.
It is greatly affected by the pressure receiving area S of 35. That is, the maximum generated load and the maximum generated speed are determined by the following equations.

Fmax = Pmax × S, Vmax = Qmax / S, where Pmax = maximum pressure of the oil acting on the cylinder hole 32 Qmax = maximum flow rate of the oil flowing into and out of the cylinder hole 32

Therefore, in the conventional example, since the pressure receiving area S of the pressure receiving portion 35 is constant, the maximum generated load and the maximum generated speed are reduced.
It is determined by the performance of the servo valve 36 and the performance of the servo valve 36, and the piston 33 can be reciprocated only at the load up to the maximum generation load and the speed up to the maximum generation speed, and there is a problem that versatility is poor. .

The present invention solves the above problems,
It is intended to provide a reciprocating piston device excellent in practicability and versatility that can arbitrarily realize the maximum generated load and the maximum generated speed that the piston can exert by setting the pressure receiving area of the pressure receiving portion of the piston arbitrarily. is there.

[0010]

The gist of the present invention will be described with reference to the accompanying drawings.

[0011] A cylinder 1, a piston 3 slidably fitted in a cylinder hole 2 in the cylinder 1, and a fluid injecting / injecting device for injecting fluid into and out of the cylinder hole 2 to reciprocate the piston 3. And a reciprocating piston device provided with two or more divided cylinder holes 2a in the cylinder 1.
2b is provided, the piston 3 is inserted through each of the divided cylinder holes 2a and 2b, and the piston 3 is provided with two or more pressure receiving portions 5a and 5b for receiving fluid pressure,
The two or more pressure receiving portions 5a and 5b are disposed in the divided cylinder holes 2a and 2b, respectively, and the fluid injecting / injecting device 4 has a switching device 6 for injecting and injecting a fluid into any of the divided cylinder holes 2a and 2b.
Provided in the reciprocating piston device.

Further, the reciprocating piston device according to the first aspect is characterized in that the pressure receiving areas of the respective pressure receiving portions 5a and 5b are set to be different.

Further, in the reciprocating piston device according to any one of claims 1 and 2, two or more divided cylinder holes 2a and 2b are arranged in series. Things.

The reciprocating piston device according to any one of claims 1 to 3, wherein the reciprocating piston device is a servo actuator.

[0015]

When the fluid is poured into or out of an arbitrary divided cylinder hole by the switching device while driving the fluid injecting / injecting device, the fluid pressure is applied only to the pressure receiving portion provided in the arbitrary divided cylinder hole. Accordingly, the maximum generated load and the maximum generated speed that the piston can exert are determined by the fluid pressure and the fluid amount applied to the arbitrary pressure receiving portion.

Since the present embodiment is constructed as described above, the reciprocating piston device is excellent in practicality and versatility in which the maximum generated load and the maximum generated speed that the piston can easily exert can be varied simply by operating the switching device. Becomes

[0017]

FIG. 2 shows a first embodiment of the present invention, and FIG.
Illustrates a second embodiment, which will be described below.

In the first embodiment, a cylinder 1, a piston 3 slidably fitted in a cylinder hole 2 in the cylinder 1, a fluid is poured into and out of the cylinder hole 2 to reciprocate the piston 3. A reciprocating piston device including a fluid injection / injection device 4 to be moved, wherein a cylinder 1 is provided with two divided cylinder holes 2a and 2b (hereinafter, a first divided cylinder hole 2a, a second divided cylinder hole 2b, Each), the piston 3 is inserted through the first divided cylinder hole 2a and the second divided cylinder hole 2b, and the piston 3 is provided with two pressure receiving portions 5a and 5b for receiving the liquid pressure (hereinafter, referred to as the following). The first pressure receiving portion 5a is disposed in the first divided cylinder hole 2a, and the second pressure receiving portion 5b is disposed in the second divided cylinder hole 2b. , The fluid injection / injection device 4 is the first A fluid can be poured into and out of the split cylinder hole 2a and the second divided cylinder hole 2b, respectively. The fluid pouring / injecting device 4 is provided with a switching device 6 for pouring fluid into and out of any of the divided cylinder holes 2a and 2b. Is what it is.

The first divided cylinder hole 2a and the second divided cylinder hole 2b are arranged in series in the cylinder 1, and the piston 3 connects the first divided cylinder hole 2a and the second divided cylinder hole 2b in the series state. It is provided so as to penetrate in a straight line state.

Incidentally, the first divided cylinder hole 2a and the second divided cylinder hole 2b may be arranged in parallel, but in this case, the shape of the piston 3 becomes complicated.

The first divided cylinder hole 2a and the second divided cylinder hole 2b have the same inner diameter.

The first pressure receiving portion 5a and the second pressure receiving portion 5b having the same pressure receiving area are provided in the first divided cylinder hole 2a and the second divided cylinder hole 2b, respectively.

The first pressure receiving portion 5a and the second pressure receiving portion 5b
A flange-shaped member that protrudes in a direction perpendicular to the reciprocating direction of the piston 3 is employed. The pressure receiving surfaces of the pressure receiving portion are the right side surface and the left side surface of the pressure receiving portion in FIG.

The piston 3 has one end (the left end in FIG. 2) protruding from the cylinder 1, and the protruding portion 7 is connected to a vibration generator or the like of a vibration test device.

The fluid supply / discharge device 4 comprises a tank 8 for storing a fluid, a pump 9, and a servo valve 10 for controlling the fluid discharged from the pump 9 to reciprocate the piston 3. ing.

The servo valve 10 pressurizes the left and right sides of the pressure receiving portion in FIG. 2 with the fluid, and presses the pressure receiving portion to the left or right by a pressure difference between the left side pressurization and the right side pressurization. The piston 3 is caused to reciprocate by alternately generating a pushing motion from the left side and a pushing motion from the right side.

Reference numeral 11a denotes a first fluid injection port for injecting fluid to the right of the first divided cylinder hole 2a, 11b denotes a second fluid injection port for injecting fluid to the left of the first divided cylinder hole 2a, and 11c denotes A third fluid injection port 11d for injecting fluid to the right of the second divided cylinder hole 2b, and a fourth fluid injection port 11d for injecting fluid to the left of the second divided cylinder hole 2b.

Reference numeral 12 denotes a first fluid injecting / injecting conduit for injecting fluid into and out of the right side of the first divided cylinder hole 2a and the right side of the second divided cylinder hole 2b. Further, the first fluid injection / injection line 12 is branched in the middle, one first fluid injection / intake line 12a is communicated with the first fluid injection / inlet port 11a, and the other first fluid injection / inlet line 11a. The inlet / outlet pipe 12b is connected to the third fluid inlet / outlet 11c. When the fluid is injected into the left side of the first divided cylinder hole 2a or the left side of the second divided cylinder hole 2b, the first fluid injection / pipe line 12 is located on the right side of the first divided cylinder hole 2a. And, it becomes a return conduit for the fluid injected into the right side of the second divided cylinder hole 2b to return to the tank 8 side.

Reference numeral 13 denotes a second fluid injecting / injecting conduit for injecting fluid into and out of the left side of the first divided cylinder hole 2a and the left side of the second divided cylinder hole 2b. The second fluid injecting / injecting line 13 is branched on the way, one of the second fluid injecting / inleting lines 13a is communicated with the second fluid injecting / inlet port 11b, and the other second fluid injecting / inlet line 11b. The inlet / outlet pipe 13b is connected to the fourth fluid inlet / outlet 11d. Note that, when fluid is injected into the right side of the first divided cylinder hole 2a or the right side of the second divided cylinder hole 2b, the second fluid injection / injection conduit 13 is located on the left side of the first divided cylinder hole 2a. A return pipe for returning the fluid injected into the left side of the second divided cylinder hole 2b to the tank 8 side.

Further, the other first fluid injection / injection line 12
A first solenoid valve 6a and a second solenoid valve 6b are provided as the switching device 6 in the b and the other second fluid inflow / outflow pipeline 13b, respectively.

The first solenoid valve 6a and the second solenoid valve 6b
Is connected to the tank 8 via return fluid lines 14a and 14b.

Similarly, the servo valve 10 is communicated with the tank 8 via a return fluid line 15.

Reference numeral 16 denotes a partition body for forming the first divided cylinder hole 2a and the second divided cylinder hole 2b in the cylinder 1, and 17 denotes a cover body for concealing the other end of the piston 3.

The operation of the first embodiment will be described below.

The first solenoid valve 6a and the second solenoid valve 6b are controlled, and the pressure of the fluid discharged from the pump 9 (in this case, oil as a fluid, the same applies hereinafter) acts on the second cylinder hole 2b. Instead, it is set so that it acts only on the first cylinder hole 2a, and the fluid that is injected and discharged from the second cylinder hole 2b by the reciprocation of the piston 3 is injected into the tank 8.

Subsequently, the pump 9 is driven and the servo valve 10
, The fluid is injected into the first fluid supply / discharge conduit 12. At this time, the fluid is injected into the right side of the first cylinder hole 2a via the first fluid outlet 11a, but controlled by the first solenoid valve 6a, the third fluid outlet 11c.
Is not injected into the right side of the second cylinder hole 2b via the hole. Therefore, by injecting the fluid into the right side of the first cylinder hole 2a, only the first pressure receiving portion 5a receives the fluid pressure from the right side.

In this state, the piston 3 moves to the left by the fluid pressure received by the first pressure receiving portion 5a from the right. Further, by the movement of the piston 3, the fluid stored on the left side of the first pressure receiving portion 5a and the second pressure receiving portion 5b returns to the tank 8 via the second fluid injection / injection pipe 13, and The right side of the pressure receiving portion 5b sucks up the fluid from the tank 8.

Subsequently, the pump 9 is driven and the servo valve 10
, The fluid is injected into the second fluid injection / pipe line 13. At this time, the fluid is injected into the left side of the first cylinder hole 2a via the second fluid outlet 11b, but the fourth fluid outlet 11d is controlled by the control of the second solenoid valve 6b.
Is not injected to the left side of the second cylinder hole 2b via the hole. Therefore, by injecting the fluid into the left side of the first cylinder hole 2a, only the first pressure receiving portion 5a receives the fluid pressure from the left side.

In this state, the piston 3 moves to the right due to the fluid pressure received by the first pressure receiving portion 5a from the left. Further, by the movement of the piston 3, the fluid stored on the right side of the first pressure receiving portion 5a and the second pressure receiving portion 5b returns to the tank 8 via the first fluid injection / injection pipe 13, and The left side of the pressure receiving portion 5b sucks up the fluid from the tank 8.

That is, when the above operation is repeated, the piston 3 reciprocates only by the fluid pressure acting alternately from the left and right of the first pressure receiving portion 5a (hereinafter, referred to as a first use mode).

On the other hand, the first solenoid valve 6a and the second solenoid valve 6b
Is controlled so that the pressure of the fluid discharged from the pump 9 acts on both the first cylinder hole 2a and the second cylinder hole 2b, the following is obtained.

By driving the pump 9 and controlling the servo valve 10, a fluid is injected into the first fluid supply / discharge conduit 12. At this time, by the control of the first solenoid valve 6a, the fluid flows through the first fluid outlet 11a and the third fluid outlet 11c to the right of the first cylinder hole 2a and the second cylinder hole 2b.
Of the first pressure receiving portion 5a
And both the second pressure receiving portion 5b receives the fluid pressure from the right side.

In this state, the fluid pressure received by both the first pressure receiving portion 5a and the second pressure receiving portion 5b from the right causes the piston 3 to move to the left. Further, the movement of the piston 3 causes the first pressure receiving portion 5a and the second pressure receiving portion 5a to move.
The fluid stored on the left side of b returns to the tank 8 via the second fluid injection / intake line 13.

Subsequently, the pump 9 is driven and the servo valve 10 is operated.
, The fluid is injected into the second fluid injection / pipe line 13. At this time, by the control of the second solenoid valve 6b, the fluid is supplied to the second fluid outlet 11b and the fourth fluid outlet 11b.
It is injected into both the left side of the first cylinder hole 2a and the left side of the second cylinder hole 2b via 11d, and both the first pressure receiving portion 5a and the second pressure receiving portion 5b receive the fluid pressure from the left side. Will be.

In this state, the piston 3 moves to the right in FIG. 2 due to the fluid pressure received by both the first pressure receiving portion 5a and the second pressure receiving portion 5b from the left side. In addition, due to the movement of the piston 3, the fluid stored on the right side of the first pressure receiving portion 5 a and the second pressure receiving portion 5 b returns to the tank 8 via the first fluid injection / injection pipe 13.

That is, when the above operation is repeated, the piston 3 reciprocates by the fluid pressure acting alternately from the left and right of the first pressure receiving portion 5a and the second pressure receiving portion 5b (hereinafter, referred to as a second mode of use). ).

Comparing the first use mode and the second use mode, since the pressure receiving area of the first pressure receiving portion 5a and the pressure receiving area of the second pressure receiving portion 5b are the same, the fluid pressure acting on the piston 3 becomes Compared to the first use mode, it is doubled in the second use mode, and inevitably, the piston 3 can exert the maximum generated load twice as large in the second use mode as in the first use mode.

In the first mode of use, the first cylinder hole 2
a, the fluid from the liquid injecting / injecting device 4 is injected into and out of the piston 3, but in the second usage mode, the fluid is injected into both the first cylinder hole 2a and the second cylinder hole 2b. The flow rate of the fluid is as compared to the first use mode,
In the second mode of use, it is halved and inevitably the piston 3
In the second use mode, only the maximum generation rate of 1/2 of the first use mode can be exhibited.

As described above, since the first embodiment is constructed as described above, the fluid is injected only into any of the divided cylinder holes 2a and 2b by controlling the first solenoid valve 6a and the second solenoid valve 6b as the switching device 6. The reciprocating piston device is excellent in practicality and versatility in which the maximum generated load and the maximum generated speed can be arbitrarily changed just by entering and leaving.

In particular, in the case of a servo actuator, a simple structure is required in order to shorten the pipeline between the servo valve 10 and the cylinder hole 2 as much as possible to increase responsiveness and to reduce the frequency of occurrence of a failure. However, the first embodiment realizes versatility in spite of its simple structure, and is excellent in practicality in this respect as well.

Incidentally, the number of divided cylinder holes and the number of pressure receiving portions may be further increased, for example, three may be provided so that the maximum generated load can be tripled and the maximum generated speed can be reduced to 1/3. .

In the second embodiment, the basic structure is the same as that of the first embodiment, but the pressure receiving areas of the first pressure receiving portion 5a and the second pressure receiving portion 5b are set to be different.

Specifically, the ratio between the pressure receiving area of the first pressure receiving portion 5a and the pressure receiving area of the second pressure receiving portion 5b is set to be 2: 1.

In the second embodiment, the switching device 6 is also provided on one of the first fluid supply / discharge conduits 12a and one second fluid supply / discharge conduit 13a communicating with the first divided cylinder hole 5a. A third solenoid valve 6c and a fourth solenoid valve 6d are provided respectively. Therefore, according to the second embodiment, by controlling the first to fourth solenoid valves 6a, 6b, 6c, and 6d, fluid can be poured into and out of only the first divided cylinder hole 5a (hereinafter referred to as a first usage mode). ), The fluid is poured only into the second divided cylinder hole 5b (hereinafter, referred to as a second use mode), and the fluid is poured into and out of both the first divided cylinder hole 5a and the second divided cylinder hole 5b ( Hereinafter, this will be referred to as a third use mode).

Comparing the first, second and third modes of use, the ratio of the pressure receiving area of the first pressure receiving section 5a to the pressure receiving area of the second pressure receiving section 5b is 2: 1. The fluid pressure acting on 3 becomes 2: 1: 3 in the first usage mode: the second usage mode: the third usage mode, and the maximum generated load that the piston 3 can exert can be set in three stages.

Similarly, the flow rate of the fluid acting on the piston 3 is 1/2: 1: 1/3 in the first usage mode: the second usage mode: the third usage mode, and the piston 3 can exert its effect. The maximum generated load can also be set in three stages.

As described above, the second embodiment is constructed as described above. Therefore, by changing the pressure receiving area by the pressure receiving portion, the maximum load and the maximum speed can be arbitrarily changed in a stepwise manner. The reciprocating piston device excels at

The rest is the same as in the first embodiment.

[Brief description of the drawings]

FIG. 1 is an explanatory side sectional view of a conventional example.

FIG. 2 is an explanatory side sectional view of the present embodiment.

FIG. 3 is an explanatory side sectional view of the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 2 Cylinder hole 2a ・ 2b Divided cylinder hole 3 Piston 4 Fluid injection / injection device 5a ・ 5b Pressure receiving unit 6 Switching device

Claims (4)

[Claims] 1. A cylinder, a piston slidably fitted in a cylinder hole in the cylinder, and a fluid injecting / injecting device for injecting a fluid into the cylinder hole and reciprocating the piston. In a reciprocating piston device, a cylinder is provided with two or more divided cylinder holes, a piston is inserted through each divided cylinder hole, and the piston has two or more pressure receiving portions that receive fluid pressure. The two or more pressure receiving portions are disposed in each of the divided cylinder holes, and the fluid injecting / injecting device is provided with a switching device that injects and injects fluid into any of the divided cylinder holes. Reciprocating piston device. 2. The reciprocating piston device according to claim 1, wherein the pressure receiving areas of the respective pressure receiving portions are set differently. 3. The reciprocating piston device according to claim 1, wherein two or more divided cylinder holes are arranged in series. 4. The reciprocating piston device according to claim 1, wherein said reciprocating piston device is a servo actuator.