JPS61286681A - High-speed position controller - Google Patents

Abstract

PURPOSE:To make a spool followable to any displacement of an input rod at high speed, by making pilot oil so as to be discharged in a large quantity in a moment by way of each passage in an orifice and a hollow rod. CONSTITUTION:A hollow rod 28 is projectingly installed in the end face exposed to a back pressure chamber of a spool 21, and projected into an intermediate oil chamber 29 formed in a valve body 20. And, this intermediate oil chamber 29 is interconnected to a pilot oil drain port 31, and an input rod 32 is fitly inserted into a sliding hole 20b inside the valve body 20. In addition, an orifice 26 is formed with both tip ends of the input rod 32 and the hollow rod 28. Likewise, this orifice 26 is interconnected to the back pressure chamber 24 through a passage of the hollow rod 28 and simultaneously interconnected to the oil chamber formed in a rear end of the input rod 32 of the sliding hole 20b through the passage formed inside the input rod 32 as well. With this constitution, the spool 21 is made followable to any displacement of the input rod 32 at high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a position control device that moves a spool or a piston at high speed following an input member.

[Conventional technology]

Conventionally, as this type of position control device, 9, for example, 11V
There was something like that shown in A.

To explain this simply, a spool 2 is housed in the valve body 1 and is biased in the valve closing direction by a spring 3. Inside the spool 2, a passage having an orifice 4 is connected to an input port 5 and a spool back pressure chamber. The spool 2 is provided with a passage S having a conical opening 8 communicating between the back pressure chamber 6 and the outlet port 7. An orifice 11 is formed between the tip of the rod 10 and follows the input rod 10. That is, when the input rod 10 is pushed to the right in the figure, the orifice 11 is closed, the pressure in the back pressure chamber 6 is increased, and the spool 2
As shown in the figure, the right edge is in close contact with the seat portion 12 to close the flow path between the inlet port 5 and the outlet port 7.

When the input rod 10 is moved to the left, the spool 2 follows it and moves to the left, separating from the seat portion 12 and opening the flow path.

[Problem that the invention seeks to solve]

However, in such a conventional spool or piston position control device, the input rod 10 was simply rod-shaped and protruded from the back pressure chamber 6 to the outside, so that the pressure of the output rod 10 exceeded the cross-sectional area of the input rod 10. It was working.

Therefore, in order to make the spool 2 or the piston follow extremely high speeds, it is necessary to significantly enlarge the diameter of the input lot 10 as well as the opening 8 and the passage S, but the outlet port 7 is connected to an external load device. In this case, a large ejection force is applied to the input lot 10.

Therefore, there was a problem in that a large input control device was required.

The object of the present invention is to solve these problems of the conventional device.

[Means for Solving the Problems] Therefore, the high-speed position control device according to the present invention has a hollow rod protruding from the end face exposed to the back pressure chamber of the spool or piston, and an intermediate oil chamber formed in the valve body. The input rod is slidably inserted into the sliding hole connected to the intermediate oil chamber in the valve body, and its tip is inserted into the intermediate oil chamber. An orifice is formed by the tip of the hollow rod that protrudes from the valve body, and a small diameter operating rod that protrudes from the valve body is fixed to the rear end.

The formed orifice is communicated with the back pressure chamber through a passage in the hollow rod, and also communicated with an oil chamber formed on the rear end side of the input rod of the sliding hole through a passage formed in the input rod. This is what I did.

[For production]

When the input rod is displaced away from the end face of the spool by operating the operating rod, a large amount of pilot oil in the back pressure chamber is instantly discharged through the formed orifice and the passage in the hollow rod.

The spool or piston can be made to follow the displacement of the input lot at high speed.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a sectional view showing a first embodiment of the invention.

In this embodiment, the spool 21 slidably housed within the valve body 20 is a non-equal area poppet spool, with a cylindrical tube formed at the tip of the spool 21 between the inlet port 22 and the outlet port 23. The V cut 21a of the shaped portion controls the opening degree of the flow path. This spool 21 has a back pressure chamber 24
A spring 25 provided therein is biased in a direction to close the flow path.

A passage 27 through which pilot oil flows from the inlet port 22 through the orifice 26 into the back pressure chamber 24 to which the end surface 21b of the spool 21 is exposed is connected to the valve body 2.
It is formed to 0.

A hollow rod 28 is protruded from the end surface 21b of the spool 21, and is slidably penetrated through the partition wall 20a into an intermediate oil chamber 29 formed in the valve body 20. The pilot oil discharge port 31 is connected to the pilot oil discharge port 30.

The hollow rod 28 is provided at its base with a plurality of radial through holes 28b that communicate the internal passage 28a with the back pressure chamber 24, and the inner peripheral surface of the tip forms a conical opening.

On the other hand, the inlet calot 32 has an intermediate oil chamber 2 in the valve body 20.
The hollow rod 28 is slidably inserted into a sliding hole 20b that is continuously formed, and its tip protrudes into the back pressure chamber 24, and the conical concave surface 32a provided on the tip surface and the tip of the hollow rod 28. An orifice 33 is formed by these.

Thereby, the pilot oil flowing into the back pressure chamber 24 through the orifice 28 is transferred to the through hole 28b of the hollow rod 28.
The oil is configured to flow out into the intermediate oil chamber 2S through the internal passage 28C and the orifice 33 formed therein, and further into the tank 30 from the pilot oil discharge port 31.

Further, at the rear end of the input rod 32, as shown in FIG.
4 are integrally fixed. The input lot 32 further includes a plurality of through passages 32b passing between the front end surface and the rear end surface thereof.
is formed.

The hydraulic pressure inside the formed orifice 33 is introduced through the through passage 32b to the oil chamber 35 formed on the rear end side of the input rod 32 of the sliding hole 20b.

The operating principle of this embodiment is the same as that of the conventional example shown in FIG. A large amount of oil can be discharged instantly. Therefore, it is possible to make the spool 21 follow the displacement of the input lot 32 at high speed.

The outer diameter D2 of the input lot 32 is the outer diameter D of the hollow rod 28.
1 or thicker by the cross-sectional area of the operating rod 34 (diameter D3). Diameter D2 is D! If it is made slightly larger, the ejection force of the operating rod 34 is canceled by the difference in cross-sectional area between the input rod 32 and the hollow rod 28.

The input lot 32 can be controlled by the operating rod 34 with extremely small operating force.

The spool 21 has a distal end portion of the hollow rod 28 and a conical concave surface 32 . The back pressure chamber 2 is automatically adjusted by an orifice 33 formed by
The input lot 32 is positioned to follow the input lot 32 while maintaining the force relationship between the pressure inside the input lot 4, the pressure in the main flow path from the inlet port 22, and the urging force by the spring 25.

FIG. 3 shows a second embodiment of the present invention, in which the same parts as in FIG. 1 are given the same reference numerals, and their explanation will be omitted.

The spool 41 in this embodiment is an equal area spool, and the opening of the flow path between the input port 22 and the outlet port 23 is determined by the gap between the distal end surface 41a, the conical seam formed on the valve body 20, and the surface 20C. control. A hollow rod 28 similar to that of the first embodiment is provided protruding from the rear end surface 41b exposed to the inside of the back pressure chamber 24.

A through passage 41d having an orifice 41c is provided in the spool 41, and the internal passage 28a of the hollow rod 28 is passed from the inlet port 22 to the through passage 41d.
Introduce pilot oil inside.

Furthermore, it is made to flow into the back pressure chamber 24 through the through hole 28b.

This second embodiment also provides the same effects as the first embodiment.

FIG. 4 shows a third embodiment of the present invention, in which the same parts as in FIG. 1 are given the same reference numerals, and their explanation will be omitted.

This embodiment uses the same poppet-shaped spool 21 as in the first embodiment, but the inlet port 42 and outlet port 43 are reversed from the embodiment of FIG.

Further, in this embodiment, pilot oil is allowed to flow into the back pressure chamber 24 from the inlet port 42 through a passage 44 having an orifice formed in the valve body 20.

Furthermore, an oil passage 47 with a solenoid valve 45 and an orifice 46 inserted is provided externally, and a port 4 formed in the body 20 is provided.
8.49, and this path also connects to the inlet port 42.
The structure is such that pilot oil can flow from the back pressure chamber 24 into the back pressure chamber 24.

The operating rod 34 can be operated with high precision by a proportional solenoid 50 with a position sensor.

By the way, the purpose of this invention is to enable high-speed movement of the spool in one direction (to the left in Fig. 4) with a small operating force, and moving the spool in the other direction (to the right in Fig. 4) has not been considered. Since it is outside, a small pilot flow rate determined by the diameter of the orifice is generally sufficient.

However, if it is desired to control movement in the other direction at high speed, it is sufficient to increase the pilot flow rate by increasing the orifice diameter only during the spool movement.

This third embodiment is used in such a case, and the solenoid valve 45
By opening the orifice, pilot oil flows into the back pressure chamber 24 even through the orifice 4 days, producing the same effect as increasing the diameter of the orifice 26.

FIG. 5 shows a fourth embodiment of the present invention, in which the same parts as in FIG. 1 are given the same reference numerals, and their explanation will be omitted.

Spool 51 in this embodiment is an equal area spool similar to spool 41 of FIG. This is done from the supply source 53.

By the way, the spool is controlled to follow the input rod,
When input lots are moved at extremely high speeds.

It is also conceivable that the spool moves with a certain delay in position, and that the input wood and hollow rod eventually collide.

In this embodiment, the orifice 33 formed by the tip of the input rod 32' and the tip of the hollow rod 28 protruding from the spool 51 is formed into a two-stage constriction shape, so that the hollow rod 28 collides with the input rod 32' at high speed. Before this occurs, a cushioning effect is applied to decelerate the vehicle, and position tracking is then performed.

FIG. 6 is an enlarged view of the main part of FIG. 5, and FIG. 7 is a velocity diagram thereof. For example, if the input lot 32' momentarily moves to the position shown in the upper side of FIG. 6, the hollow rod 28 internal passages 28. The pressure oil in the back pressure chamber 24 is discharged into the intermediate oil chamber 2S as shown by the arrow A, and the discharge flow causes the spool 51 and the hollow rod 28 integrated therewith to move in the direction of the arrow B at high speed.

Then, as the corner d of the hollow rod 28 approaches the corner a of the input lot 32', its area is rapidly closed. After that, the speed is further reduced as the taper part 2 cylindrical surface part C sequentially covers the corner part d, and finally the sixth
As shown in the lower part of the figure, the opening X is positioned in accordance with the orifice 33.

FIG. 8 is an enlarged sectional view of the main part showing only the orifice forming part of the fifth embodiment of the present invention.

In this embodiment, the tip of the input rod 62 has a conical recess 62. A hollow rod 68 having a cylindrical recess 62c and an internal passage 68a has a tip 68c whose outer diameter is made smaller than the main diameter to form a stepped shape, and the tip is made into a tapered surface to provide input. Conical recess 6 at the tip of the rod 62
An orifice 33 is formed between 2a and the cylindrical recess 62C.

This provides the same cushioning effect as in the fourth embodiment described above.

The fourth of these. According to the fifth embodiment, even if the spool is followed and moved at extremely high speed, the input rod and the hollow rod will not collide and be damaged.

FIG. S shows a sixth embodiment of the invention, and FIGS.
Components similar to those in the figure are designated by the same reference numerals.

This example is an example in which the spool shape is always open,
It has a structure that further reduces the operating force of the input rod.

That is, the spool 71 of this embodiment is connected to the inlet port 2.
The end surface 7 has a cylindrical portion 71b provided with an open lower portion 1a that communicates with the outlet port 23 and the end surface 7 exposed to the back pressure chamber 24.
A hollow rod door 8 is provided protruding from 1C and protrudes into the intermediate oil chamber 29.

The hollow rod door 8 forms an internal passage 78a and a through hole 78b like the hollow rod 28 in FIG.
The outer diameter D5 of 8C is the diameter D of the main diameter portion inside the back pressure chamber 24! It's bigger.

In the input lot 72, the tip end 78c of the hollow rod door 8 and the tip surface 72a forming the orifice 33 are planar,
The oil chamber 73 has a large diameter portion 72c having a larger diameter (D4) than the main diameter portion (diameter D2) at the rear end portion that fits into the sliding hole 20b, and is formed between the oil chamber 73 and the valve body 20 due to the diameter difference. is communicated with the tank port 74.

Further, a shuttle valve 75 is provided in the valve body 20 to allow pilot oil to flow into the back pressure chamber 24 from the inlet port 22 via the passage 27 and the shuttle valve 75° orifice 26, and also to supply pilot oil from the pilot oil supply source 53. The pilot oil supplied to the port 52 is transferred to the shuttle valve 75.
It is also possible to flow into the back pressure chamber 24 through the orifice.

Further, the pilot oil discharge port 31 communicating with the intermediate oil chamber 2 can be switchably connected to a hydraulic power source 77 and a tank 78 via a solenoid valve 76 which is a two-position switching valve.

Normally, the pilot oil discharge port 31 is connected to the tank 7.
The solenoid valve 76 is switched to communicate with the back pressure chamber 24 through the orifice 26 in a steady state.
Although a small amount of pilot flow flowing into the hydraulic pressure source 7 flows out from the pilot oil discharge port 31, in the event of an emergency operation, the solenoid valve 76 is connected to the pilot oil discharge port 31.
By switching so that it is connected to 7, the intermediate oil chamber 2
When high pressure is applied to 9, the spool 71 can be moved to the right end (fully open in the figure) regardless of the state of the input lot 72.

However, at this time, due to the pressure increase in the intermediate oil chamber 2S, a pushing force to the left acts on the operating rod 32 (diameter D3) due to the pressing force on the cross-sectional area.

In this embodiment, by providing the input lot 72 with a large diameter portion 72C, a pressing force that offsets this ejection force is generated and balanced.

By appropriately selecting the relationship between these diameters D1 to D5, it is possible to maintain the balance as described above and control with extremely small operating force. When the input rod 72 (diameter D2) is further made thicker, a retracting force always acts, and when the operating force is removed, the fully open state shown in the figure is achieved. Conversely, if the input lot 72 is made thinner.

Ejection force always acts.

FIG. 10 shows a seventh embodiment of the invention, that is, an example in which the position of a piston is controlled, and the same parts as in FIG. 1 are given the same reference numerals.

A part of the piston 81 that integrates the output lot 81j,
Groove 81. as shown by the dashed line. By forming the land portion 81b, a switching valve is formed.

82 is an inlet port provided in the valve body 20, and 83 is an outlet port.

A hollow rod 28 is provided protruding from the end face of the large diameter portion 81C within the back pressure chamber 24 of the piston 81, and is made to protrude into the intermediate oil chamber 2S.

The oil chamber 84 formed by the diameter difference between the main diameter part (diameter Da) and the large diameter part (diameter Db) of this piston 81 is connected to the pilot oil supply port 52, and pilot oil is supplied from the pilot oil supply source 53. From this oil chamber 84, pilot oil flows into the back pressure chamber 24 through a passage 85 having an orifice 26 formed in the valve body 20.

The input lot 32 is formed in exactly the same way as the input lot in the embodiment of FIG.

Here, the dirt Da of the piston 81 and the diameter D of the large diameter portion 81C
b is appropriately selected depending on the direction and magnitude of the load acting on the output lot 81f. In this case, the effective action area for pressing the piston 81 leftward from the oil chamber 84 side is (π/4) (
Db''-Da2), and the effective action area for pressing the piston 81 to the right from the back pressure chamber 24 side is (π/4)Db2.

For example, when a leftward pushing force of an appropriate magnitude is acting on the output lot 91j, D b = D a may be set.

〔Effect of the invention〕

As described above, the high-speed position control device according to the present invention can position the spool or piston in one direction by following the position of the input rod at extremely high speed.

Furthermore, the operating force of the input rod can be extremely small, and the operating force can be zero or in the direction of protrusion or retraction.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the invention. FIG. 2 is a perspective view of the main parts of the input lot as seen from the rear end side, FIG. 3 is a vertical sectional view showing a second embodiment of the invention, and FIG. 4 is a third embodiment of the invention. FIG. 5 is a vertical cross-sectional view showing a fourth embodiment of the present invention. FIG. 6 is an enlarged explanatory view of the main part of FIG. 5, FIG. 7 is a speed diagram thereof, and FIG.
The figure is a longitudinal sectional view of a sixth embodiment of the invention, and FIG. 10 is a longitudinal sectional view of a seventh embodiment of the invention. FIG. 11 is a longitudinal sectional view showing an example of a conventional spool position control device. 20...Valve body 20b...Sliding hole 21.
41, 51, 71.81...Spool 22.42, 8
2... Inlet port 23.43.83... Outlet port 24... Back pressure chamber 25... Spring 26
．． 41c... Orifice 28.6B, 78... Hollow rod 29... Intermediate oil chamber 31... Pilot oil discharge port 32.32', 72... Input rod 33... Forming orifice 34...・Operation rod 35.73.84
... Oil chamber 50 ... Proportional solenoid with position sensor 52 ... Pilot oil supply port Figure 6 Procedural amendment (voluntary) January 21, 1985 Michibe Uga, Commissioner of the Patent Office 1, of the incident Indication Patent Application No. 60-128695 2, Title of the invention: High-speed position control device 3, Relationship with the amended person case Patent applicant: 2-16-46 Minami Kamata, Ota-ku, Tokyo (338)
Tokyo Keiki 4, Agent 1-20-5 Higashiikebukuro, Toshima-ku, Tokyo (1) Scope of Claims column in Book M (2) Column for detailed description of the invention in Book F and III rq )a
smrz/7'+rp stone ty>ps village explanation no mtr'
;') 1 to 6, Contents of amendment (1) The scope of claims in the specification is amended as shown in the attached sheet. (2) The following statement is inserted between the second and third lines of page 15 of the same book. r As shown in Fig. 6a, if the gap between the outer diameter of the hollow rod 28 and the cylindrical surface portion C of the input rod 32' is reduced to create a snug fit, the hollow rod is integrated with the spool. 28 is a forming orifice 33 formed by the tip corner part d and the tapered part of the input rod 32'.
' is set to an amount commensurate with the orifice 33. In this case, there is a considerable distance between the tip of the hollow rod 28 and the bottom surface of the cylindrical surface portion C of the input rod 32', and there is no fear of collision. Further, by providing a notch or the like at the tip of the hollow rod 28, it is possible to further reduce the speed change during one positioning. ” (3) Delete “further” in the first line of page 16 of the same book. (4) Correct the line 11 on the same page of the same book to read, ``J, which is larger, is almost equal to r.'' (5) The following statement is inserted between lines 18 and 19 on the same page of the same book. "Then, each diameter is formed into D2ΦDs." (6) From page 17, line 7 of the same book to page 18, line 15, "Furthermore, it acts." Correct as shown below. Furthermore, the pilot oil discharge port 31 communicating with the intermediate oil chamber 2S is connected to the solenoid valve 7, which is a two-position switching valve.
6 can be closed or can be switched connected to a tank 77. Normally, the pilot oil discharge port 31 is connected to the tank 7.
The solenoid valve 76 is switched to communicate with the back pressure chamber 24 through the orifice 26 in a steady state.
A small amount of pilot flow flowing into the input lot flows out from the pilot oil discharge port 31, but in the event of an emergency operation, the solenoid valve 76 is switched so that the pilot oil discharge port 31 is closed, regardless of the state of the input lot 72. The spool 71 can be moved to the right end (fully open in the figure). However, at this time, due to the pressure increase in the intermediate oil chamber 2S, a pushing force to the left acts on the operating rod 34 (diameter D3) due to the pressing force on the cross-sectional area. In this embodiment, by providing the input lot 72 with a large diameter portion 72c, a pressing force that offsets this ejection force is generated and balanced. By appropriately selecting the relationship between these diameters D1 to D5, it is possible to maintain the balance as described above and control with extremely small operating force. When the large diameter portion 72c (diameter D4) of the input rod is further made thicker, a retraction force is always applied, and when the operating force is removed, the fully open state shown in the figure is achieved. On the other hand, if you make it thinner, ejection force will always act on it. (7) "Output lot 81f" on page 19, line 19 of the same book is corrected to IR exit lot 81j. (8) "Output lot 91j" on page 20, line 5 of the same book,
Corrected to "output lot 81j." (9) The following statement is inserted between lines 3 and 4 on page 21 of the same book. Figure 6a is an enlarged explanatory view of the main part showing a slightly different example of the same part as Figure 6.'' (10) Figure 6a of the attached drawing is between ``Figure 6'' and ``Figure 7'' of the drawing. Add a figure. (11) "Figure 9" of the drawing is corrected as shown in the attached corrected drawing. Above (Attachment) Claim 1: A spool or piston that continuously adjusts the opening depending on the position between an inlet port and an outlet port formed in a valve body, and an input rod that controls the position of the spool or piston. and. Oil is caused to flow from the inlet port or the pilot oil pressure supply port into the byron 1 through an orifice into a back pressure chamber to which the end surface of the spool or piston is exposed, and a hollow rod is provided protruding from the end surface of the spool or piston. and protrude into an intermediate oil chamber formed in the valve body,
The intermediate oil chamber is communicated with a pilot oil discharge port. The input rod is slidably inserted into a sliding hole formed in the valve body so as to be continuous with the intermediate oil chamber, and its tip protrudes into the intermediate oil chamber to form an orifice with the tip of the hollow rod. while forming a small-diameter operating rod protruding from the outside of the valve body at the rear end of the input rod, communicating the forming orifice with the back pressure chamber through a passage in the hollow rod, and . A high-speed position control device, characterized in that the sliding hole is also communicated with an oil chamber formed on the rear end side of the input lot through a passage formed in the input lot. 2. The high-speed position control device according to claim 1, wherein the diameter (D2) of the human-powered rod is approximately equal to the outer diameter (D5) of the tip of the hollow rod. A. The hollow rod is characterized in that the outer diameter (D5) of the tip thereof is made larger than the diameter (D) of the main diameter part located in the back pressure chamber. A high-speed position control device as described in Tatewam Taku.-5- A patent characterized in that the hollow rod has an outer diameter (D5) of the tip thereof equal to a diameter (D1) of the main diameter part located in the back pressure chamber. The high-speed position control device according to Claims 1 and 1(7)jN. A high-speed position control device according to Claims 1 and 1, characterized in that the diameter (D1) is adjusted. It has a large diameter part that is thicker than the diameter part, and an oil chamber formed within the valve body by the difference between the diameter (D4) of the large diameter part and the diameter (D2) of the main diameter part is connected to the tank port. Claim 1:2
and 4. The high-speed position control device according to any one of items 4 to 16-1. l The shape of the tip of the input lot and the corresponding tip of the hollow rod is determined by the WJ person when the two approach each other until they reach the proper relative position, and the opening amount of the orifice formed by the two is adjusted to the proper opening. 2. The high-speed position control device according to claim 1, wherein the high-speed position control device has a shape in which the amount decreases gradually or stepwise. 1. The high-speed position control device according to claim 1, wherein the spool or the piston is biased in one direction by a spring provided in the back pressure chamber.

Claims (1)

[Claims] 1. A spool or piston that continuously adjusts the opening degree depending on the position between an inlet port and an outlet port formed in a valve body, and an input rod that controls the position of the spool or piston. and allowing pilot oil to flow from the inlet port or pilot oil pressure supply port through an orifice into a back pressure chamber to which an end surface of the spool or piston is exposed, and a hollow rod protruding from the end surface of the spool or piston. and protrude into an intermediate oil chamber formed in the valve body,
The intermediate oil chamber is communicated with the pilot oil discharge port, and the input rod is slidably inserted into a sliding hole formed in the valve body so as to be continuous with the intermediate oil chamber, and the tip thereof is connected to the back. An orifice is formed by the tip of the hollow rod that protrudes into the pressure chamber, while a small-diameter operating rod that protrudes from the outside of the valve body is fixed to the rear end of the input rod to form an orifice. , the hollow rod communicates with the back pressure chamber through a passage, and also communicates with an oil chamber formed on the rear end side of the input rod of the sliding hole through a passage formed in the input rod. Features a high-speed position control device. 2. The high-speed position control device according to claim 1, wherein the diameter (D_2) of the input rod is approximately equal to the outer diameter (D_5) of the tip of the hollow rod. 3. According to claim 1 or 2, the hollow rod has an outer diameter (D_5) of the tip thereof larger than a diameter (D_1) of the main diameter part located in the back pressure chamber. high-speed position control device. 4. The high-speed vehicle according to claim 1 or 2, wherein the hollow rod has an outer diameter (D_5) of the tip thereof equal to a diameter (D_1) of the main diameter part located in the back pressure chamber. Position control device. 5. According to claim 1 or 2, the hollow rod has an outer diameter (D_5) of the tip thereof smaller than a diameter (D_1) of the main diameter part located in the back pressure chamber. high-speed position control device. 6 The input rod has a large diameter part thicker than the main diameter part at the rear end, and the diameter of the large diameter part (D_4) and the diameter of the main diameter part (D_2
6. The high-speed position control device according to claim 1, wherein the oil chamber formed in the valve body is connected to the tank port by a difference in the distance between the valve body and the tank port. 7. The shape of the tip of the input rod and the corresponding tip of the hollow rod are adjusted so that the opening amount of the orifice formed by the two is adjusted to the normal shape when the two approach each other until they reach the normal relationship position. The high-speed position control device according to any one of claims 1 to 6, characterized in that the opening amount is gradually or stepwise reduced toward the opening amount. 8. The high-speed position control device according to any one of claims 1 to 7, wherein the spool or the piston is biased in one direction by a spring provided in the back pressure chamber. .