JPS6127381A - Poppet valve drive system - Google Patents

Abstract

PURPOSE:To prevent seating of poppet valve onto the valve seat with shock by temporarily interrupting supply of working fluid to the pressure chamber. CONSTITUTION:When the groove section 18 is located lower than the fluid path 15 and the discharge path 19, the working liquid is fed only to the supply system for the pressure chamber 8 thus to energize the poppet valve 3 in the closing direction. Upon motion of the groove section 18 to the position communicatable with said paths 15, 19, the working liquid in said path 15 is fed through the groove section 18 to said path 19 thus to considerably reduce the pressure of fluid to be fed to the pressure chamber 8 and to lose the energizing force in the closing direction. Consequently, the poppet valve 3 can be seated gradually on the valve seat 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a poppet valve device, and more particularly to a poppet valve drive device that improves the durability of the valve device by seating the valve seat without impact.

[Prior Art] Poppet valve devices are widely used as valve devices that appropriately control the opening and closing of intake and exhaust passages formed in compressors, internal combustion engines, high-pressure gas furnaces, and the like.

This poppet valve device has used a cam mechanism or a hydraulic mechanism to open and close the poppet valve.

[Problems to be solved by the invention] However, when the poppet valve is seated on the valve seat, a large impact force is generated between them, resulting in scratches on the valve seat surface and frequent damage to the poppet valve device. It is known to cause When the poppet valve is opened and closed by a cam mechanism to buffer this impact force, it is important to form the cam into a shape that decelerates the poppet valve when it attempts to sit. This has not been realized as it would lead to larger size.

:1.In a hydraulic valve mechanism, what is the device? ! 2. In addition to being complicated and expensive, the working fluid used in the hydraulic system is an incompressible fluid, so that a sufficient effect against the above-mentioned impact force cannot be obtained.

For this reason, it is not possible to use ceramics with excellent properties for the poppet valves and valve seats, etc., and their lightweight design and
It was becoming difficult to design the cooling shape.

[Summary of the Invention 1 In order to achieve the above object, the present invention includes a poppet valve that is seated on a valve seat and provided to open and close the poppet valve, and a valve stem of the poppet valve that is slidably guided on the seat. a guide cylinder, a movable cylinder which is movably provided along the guide cylinder, forms a pressure chamber with the guide cylinder, and is connected to the valve stem; a valve-opening device for moving the poppet valve in the valve-opening direction connected to the valve; a fluid supply means provided to supply working fluid into the pressure chamber to move the poppet valve in the valve-closing direction; The pressure adjusting means is configured to adjust the fluid pressure to the pressure chamber, and the poppet valve is seated on the valve seat with a cushion. ~ In order to prevent the valve from sitting on the valve seat with an impact horn, the supply of working fluid supplied from the fluid supply device to the pressure chamber is temporarily stopped, or the supply amount is reduced. For example, the movable cylinder and poppet valve are seated on the valve I and G without shock by the force of inertia, and then the pressure regulating means is supplied or increased again to tighten the valve seat. This is to engage the object.

[Embodiment 1] Hereinafter, a preferred embodiment of the present invention will be specifically described with reference to the accompanying drawings showing an example of an internal combustion engine for a ship or the like.

As shown in FIG. 1, an intake and exhaust passage 2 is provided in the cylinder head 1 to open and close the valve seat, which is provided in the intake and exhaust passage formed from the cylinder head to the combustion chamber. A guide tube 5 is provided to slidably guide the valve stem 4 of the poppet valve 3 in the direction of the poppet valve. It is housed in a body-shaped moving cylinder 7 and is integrally connected thereto.On the other hand, when the guide cylinder 5 and the moving cylinder 7 are brought together, a pressure chamber 8 is formed inside them. is formed, and by supplying air or compressible working fluid to the pressure chamber 8, the movable cylinder 7 and the poppet valve 3 connected thereto are always urged in the valve closing direction against the valve seat 9. 1, which has a grooved bottom, while the above poppet valve 3
In order to separate the valve seat 9 from the valve seat 9 and open the suction/discharge passage 2, a valve opening device @1 is provided on the bottom surface 10 of the movable cylinder 7, which is formed of a cylinder 12 in which a piston 11 is slidably housed, for example.
3 is provided, which is configured to overcome the working fluid pressure in the pressure chamber 8 and actuate the moving cylinder 7 and the poppet valve 3 (=I).Furthermore,
The fluid supply means 17 and the pressure adjustment means 20 which seat the poppet valve 3 on the valve seat 9 without any impact force and supply working fluid to the pressure chamber 8 will be specifically explained.

A fluid supply means 17 for supplying working fluid to the pressure chamber 8 is provided in the guide cylinder 5, and is provided on the valve rods 4 of the valves 1 to 3.
It is composed of a fluid passage 15 that communicates in a direction crossing the guide hole 14 that slidably guides the pressure chamber 8, and a fluid introduction passage 16 that branches off from the passage 15 and communicates with the pressure chamber 8.
The pressure regulating means 20 also includes a groove 18 formed along the circumferential direction of the poppet valve 3, and a discharge passage 19 that is connected to the fluid passage 15 through the groove 18 (and a discharge passage 19 that supplies working fluid to the turbine 21, etc.). It consists of

That is, the groove 18 formed in the poppet valve 3 and the shaft 4a of the valve stem 4 are configured to function as a pressure regulating valve for the supplied working fluid. When the valve 3 is in the open state by the valve opening device 13, the groove portion 18 of the valve stem 4 is formed to be located below the fluid passage 15 and the discharge passage 19.

When the valve opening device 13 releases the biasing force against the moving cylinder 7, the poppet valve 3 is operated in the valve closing direction by the working fluid pressure supplied from the fluid passage 15 and the fluid introduction passage 16 to the pressure chamber 8. Then, when the groove portion 18, the fluid passage 15, and one discharge passage are connected together, the working fluid is branched to the pressure chamber 8, the turbine 21, etc., and then to the poppet valve 3. The biasing force in the valve closing direction is reduced, and the valve 1-valve 3 is operated only by inertia force. The rough groove portion closes the fluid passage 15 due to its inertia force.
After passing through the valve stem 4, the shaft 4a of the valve stem 4 opens the discharge passage 1 again.
9 is shut off, working fluid is again supplied only to the pressure chamber 8, and the poppet valve 3 is again supplied with an urging force in the valve closing direction. Therefore, the poppet valve 3 loses its acceleration in the valve closing direction due to the groove 18 and is seated on the valve seat 9 without shock by only +nt'1 no J, after which it is tightly engaged with the valve seat 9. It is designed to make it possible.

The effects of the embodiment will be explained below.

A guide cylinder 7 is provided on the cylinder head 1, and a pressure chamber 8 is formed by installing a fluid cylinder fitted movably along the guide cylinder.
One end 6 of the valve stem 4 is connected to the shaft 418, and its shaft 4a is slidably inserted into the guide tube 7, so that working fluid is supplied from the fluid supply means 17 to the pressure chamber 8. As a result, the movable cylinder 7 and the poppet valve 3 are applied with a biasing force against the valve seat 9 in the direction of closing the valve, and are tightly engaged with the valve seat 9.

In order to move this poppet valve 3 in the valve opening direction relative to the valve seat 9, when the bottom part 10 of the moving cylinder 7 is pressed by the screw 11 of the valve opening device f113, the moving cylinder 7 and the poppet valve 3 are moved. It is moved away from the valve seat 9, and the intake and exhaust passage 2
will be released.

Next, the fluid supply means 17 and the pressure adjustment means 20 for seating the poppet valve 3 on the valve seat 9 while moving it MKj will be explained.

The groove 18 of the poppet valve 3, which is slidably provided in the guide hole 14 of the guide tube 5, is provided as a pressure regulating valve, and is connected to the fluid passage 15 and the fluid introduction passage 1 that constitute the fluid supply device 17.
The system is divided into a supply system that supplies working fluid to the pressure chamber 8 such as 6, etc., and an exhaust system that supplies working fluid to the turbine 21 etc. by the groove 18 via the fluid passage 15 and the discharge passage 19.

In other words, when the poppet 3 is in the open state by the valve opening device @ 13, when the groove portion 18 is located below the fluid passage 15 and the discharge passage, the shaft of the valve stem 4 4a cuts off the flow of the working fluid to the discharge system, and the working fluid is supplied only to the supply system to the pressure chamber 8, so that the poppet valve 3 is biased in the valve opening direction.

Here, when the urging force of the valve opening device 13 is released, the poppet valve 3 is moved in the valve closing direction by the urging force of the fluid supply means 17, but the groove 18 is connected to the fluid passage 15 and one discharge passage. When moved to the communicating position, the fluid passage 15
The working fluid therein is supplied to the discharge passage 19 through the groove 18, and the fluid supply pressure to the pressure chamber 8 is significantly reduced, substantially losing the urging force on the poppet valve 3 in the valve closing direction. However, inertia force remains in the poppet valve 3, and as a result, the poppet valve 3 gradually seats on the valve seat 9.

Further, when the groove portion 18 moves through the passage 15.19, fluid is supplied to the pressure chamber 8 again, so that the biasing force within the pressure chamber 8 is restored and the poppet valve 3 is tightly engaged with the valve seat 9. It is possible. When the groove 18 moves relative to the passage 15.19, the discharge passage 19 is gradually closed and the supply pressure to the pressure chamber 8 increases. By optimally setting the position of the groove 18 with respect to the stroke, it becomes possible to arbitrarily set the opening and closing speed of the poppet valve 3, and accordingly, the poppet valve 3, valve seat 9, and each movement surface Ceramic formation and coating can be achieved, and wear resistance, heat resistance, and corrosion resistance can be improved, and the poppet valve 3 can be formed into a shape with good cooling performance.

Further, the pressure adjusting means 20 is connected to the groove portion 18 and the discharge passage 19.
Although explained in , it is possible to achieve this even if the groove portion 18 is a hole.

Next, another embodiment of the present invention will be described in detail, but since it has the same configuration except for the fluid supply means 17, the pressure adjustment means 20, and some other parts, the explanation thereof will be omitted.

As shown in FIG. 2, the poppet valve 3 which is biased in the valve opening direction by the quantity valve device 13 is
When the force is released, working fluid is supplied by the fluid supply means 17 to the pressure chamber 8 formed by the moving cylinder 7 and the guide cylinder 5. Specifically, the fluid supply means is provided in the guide tube 8, intersects with the guide hole 14 of the poppet valve 3, roughly passes through it, and is connected to the fluid group inlet 16 to communicate with the pressure chamber 8 ( In addition, the pressure adjustment means 20 is
~First and second grooves 18 and 188 provided at intervals along the circumferential direction of the valve stem 4 of the valve, and the first and second grooves 18 and 188
The first groove 18 and the shaft 4a have the same diameter as the fluid passage 15, and the second groove 18a has the same diameter as the poppet. The lift height J: of the valve 3 is formed to be slightly small.

That is, when the poppet valve 3 is in the open state by the intervalve device 13, 1. F fluid passage 15 and fluid introduction passage 1
6 are in communication with each other through the second groove portion 18a,
As a result, the working fluid is supplied to the pressure chamber 8, and a biasing force is applied to the poppet valve 3 in the valve closing direction. , the poppet valve 3 is moved in the valve opening direction together with the moving cylinder 7 by the fluid pressure in the pressure chamber 8;
When the shaft portion 4a of the valve stem 4 is moved to position 5, the passage 15 is temporarily closed and the supply of working fluid to the pressure chamber 8 is stopped or reduced by the section of the shaft portion 4a. It turns out. However, the inertia force remains in the valves 1 to 3 in that state, and the valves try to move further in the valve closing direction and sit on the valve seat 9. In this state, the valve seat 9 is removed without any impact.
The second groove portion 1 of the valve stem 4 is inserted into the fluid passage 15 just before the valve stem 4 is seated.
8a, the fluid pressure to the pressure chamber 8 is restored again, but to the poppet valve 3! Since there is no acceleration and acceleration stroke with fv forces, the poppet valve 3 is configured to be further tightly engaged after seating on the valve seat 9 without impact forces.

An auxiliary passage 15a' is provided in the pressure chamber 8 which is branched from the fluid passage 15 of the guide tube 5 in Fig. 1 and is branched from the fluid passage 15 of the guide cylinder 5 in Fig. 2, and the opening/closing of these passages is controlled by detecting the fluid pressure. For example, when the electromagnetic on-off valves 22 and 23 are opened, the poppet valve 3 is moved in the closing direction by fluid pressure, absorbing the slack in the piston 11 of the poppet valve device 13. (consisting of the second
In the figure, there is a twist between the piston 11 and the moving cylinder 7.
The piston 11 is provided with a buffer member 24 such as an oil spring, and
It is configured to eliminate play with the moving cylinder 7.

[Effect of the invention] According to the present invention, the following excellent effects can be achieved.

(1) A groove is provided on the valve stem of the poppet valve, and the groove and the shaft of the valve stem function as an on-off valve for the fluid passage.The structure is such that the poppet valve is seated in a cushioned manner on the valve seat. is easy and can reduce costs.

(2) Since a compressible fluid such as air is used as the working fluid, the poppet valve is not rapidly accelerated and no impact force is generated, and the poppet valve seat is tightly engaged to prevent leakage of gas, etc. can.

(3) Since impact force can be reduced, poppet valves and valve seats can be made lighter and easier to design with cooling structures, such as ceramic molding or ceramic coating with excellent wear resistance, heat resistance, and corrosion resistance. (4) Since impact force can be reduced, noise can be reduced.

(!)) It is possible to efficiently use the working fluid that controls the speed of the poppet valve that supplies the fluid supplied to the pressure chamber to the Akicomulator or turbine, etc., without waste.

6) Since the pressure inside the pressure chamber can be detected by providing an open 111 valve in the passage communicating with the pressure chamber, the poppet valve is not maintained in an open state.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a poppet valve device showing a preferred embodiment of the present invention, and FIG. 2 is a schematic sectional view not showing another embodiment. In the figure, 3 is a poppet valve, 4 is a valve stem, 5 is a guide cylinder, 7 is a moving cylinder, 8 is a pressure chamber, 9 is a valve seat, 17 is a fluid supply means, and 20 is a pressure adjustment means. Patent applicant: Ishikawajima-Harima Heavy Industries Co., Ltd. Representative patent attorney: Nobu Kinutani, Yutaka 1st

Claims (1)

[Claims] A poppet valve seated on a valve seat to open and close the poppet valve, a guide tube for slidably guiding a valve stem of the poppet valve to the valve seat, and a guide tube movable along the guide tube. , and a movable cylinder which forms a pressure chamber with the guide cylinder and is connected to the valve stem, and which is connected to the movable cylinder to move the poppet valve connected to the movable cylinder in the valve opening direction. a valve opening device; a fluid supply means provided to supply working fluid into the pressure chamber to move the valve in the valve closing direction; and a fluid supply means for adjusting the fluid pressure from the fluid supply means to the pressure chamber; A poppet valve driving device comprising: a pressure regulating means provided to be cushioned and seated on the valve seat.