JPH02283965A - Sealing device with reverse flow mechanism - Google Patents

Abstract

PURPOSE:To obtain a sealing device which is simple in its structure, low priced and excellent in its performance by completely preventing leakage of a working fluid from a piston ring portion at the time of outgoing motion and very easily passing the working fluid at the time of returning motion. CONSTITUTION:At the time of outgoing motion of a piston 1, a working fluid in a compression chamber 4 is passed through a clearance 18 formed between the returning motion contact surface 39 of a piston ring 3 and the upper surface of a ring groove 16 and a radial groove 40 and introduced into a sealing back surface of a ring 3 and a tension ring 17 to push the ring 3 outward and press same to the inner wall surface of a cylinder 7. At that time, the leakage of a working fluid is completely prevented by a special abutment shape. In an intake stroke, a sealing device is operated so that the contact surface 39 of the ring 3 is brought into contact with the upper surface of the groove 16 by the frictional force between the inner wall surface of the cylinder 7 and the outer peripheral surface of the ring 3 to form a clearance between the contact surface 33 and the lower surface of the groove 16. Even if the ring 3 closely adheres to the compression chamber side upper surface of the groove 16, a working fluid from a low pressure chamber 19 passes through the groove 40 and very easily flows into the compression chamber 4 side.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sealing device with a backflow mechanism, specifically, a reciprocating internal combustion engine, pressure! i? This is a sealing device with a backflow mechanism that completely prevents leakage of working fluid during forward movement in so-called reciprocating machines such as i-machines, fluid pressure cylinders, or Stirling engines, and allows fluid to easily pass during return movement. It is.

(Prior Art) In a reciprocating compressor that has been commonly used in the past, as shown in FIG. The large end fllj of the connecting rod 8 is attached, and the small b:11 portion of the connecting rod 8 is formed into foil so that it can rotate freely around the piston l via the piston pin 15.

A rider ring 2 is provided on the outer circumferential surface of the piston l to prevent metal contact between the piston l and the cylinder 7, and a rider ring 2 is provided to prevent metal contact between the piston l and the cylinder 7. A piston ring 3 is attached to the iM for keeping a so-called piston clearance portion airtight between the iM and the inner wall surface.

During the suction process of the piston L, that is, when the piston L is moving downward, the suction valve 11 opens due to the negative pressure in the compression chamber 4, and air is sucked through the suction pipe 13. The air compressed in the exhaust valve I
Open O and exhaust pipe! 2 and is generally stored in a tank.

However, some of the air that leaks from the piston ring 3 flows into the crankcase 5, passes through the rotation bearing of the motor, passes through the motor case, and is discharged to the atmosphere.

That is, the inside of the crankcase 5 is generally at atmospheric pressure.

As described above, the conventional compressor has a very complicated structure and is expensive.

Therefore, attach a backflow device 11') to the screw) and crank 3 at 6if.
It has been proposed, for example, in Registered Utility Model No. 1G85194G, to eliminate one of the intake valves and simplify and reduce the cost of the +74 construction by installing a sealing device that is effective. This sealing device with a backflow mechanism maintains airtightness while sliding on the inner wall surface of the cylinder or the outer circumferential surface of the shaft, and also prevents leakage from the joint between the screw ring, which has a slit on one side, and the piston ring. lI,
A back seal ring that contacts the circumferential surface opposite to the lj7 moving surface to stop lj, and a tension ring that acts to press the piston crank and back seal ring against the inner wall surface of the cylinder or the outer circumferential surface of the shaft. In order to prevent the parts of each ring from being aligned, high precision is required for each ring in order to satisfy the required performance. As a result, a rotation prevention mechanism is required, and the 14-piece sealing device becomes a complicated and expensive sealing device. However, in addition to having the same 11 problems as mentioned above, the rubber ring also has the disadvantage of poor heat resistance and oil resistance.

[Problems to be Solved by the Invention] The present invention aims to solve the above-mentioned conventional problems and provide a sealing device with a backflow device 41'4 that is simple in structure, inexpensive, and has excellent performance. ! ! I! The subject is

(!! Means for Solving Kffi) The present invention solves the above problem by providing a piston ring and a peripheral surface of the piston ring opposite to the sliding surface so as to press the piston ring against the sliding surface. One abutment end of the piston ring has the sliding surface, the forward contact side and the abutment 41 surface at the corner where the 1g moving surface and the forward contact side intersect. A concave portion opening to the piston ring is formed, and a convex portion having a shape that fits perfectly into the concave portion of the one abutment end is formed at the other abutment end, so that the convex portion can be tightly fitted to the side surface of the ring groove in which the piston ring is installed. A plurality of grooves are formed on one side of the piston ring that penetrate from the inner circumferential surface to the outer circumferential surface of the piston ring, and during forward movement, the leakage of working fluid from the piston ring part is completely prevented. This problem was solved by a sealing device with a reverse/A machine 11.Y for reciprocating machines, which is characterized by allowing objects to pass through very easily during the 1st and 2nd shifts.

[Effect]

According to the present invention, during the forward movement of the piston, for example, when the compression stroke is entered, the operation inside the compression chamber is performed. i! The i body is formed between the four surfaces of the piston ring on the compression chamber side and the upper surface of the ring): Through it, the back of the sealing device consisting of the piston ring and tensing ring is immediately guided.・The sealing device is immediately screwed into the screw!・The crank is pushed outward and pressed against the inner wall surface of the cylinder.・
(In this case, due to the special shape of the present invention, there is no leakage of working fluid from the joint B::; and complete airtightness is achieved.

During the suction stroke of the piston, the seal device ID is 1'+' between the screw I on the inner wall of the cylinder and the outer peripheral surface of the crank.
! Due to the force, the reciprocating contact surface, which is the side surface of the piston ring on the compression chamber side, comes into contact with the ground surface of the ring flS, and a gap is formed between the forward contact surface 71 and the lower 17ri of the ring 11-1, and the screw During the double movement of 1, for example, the suction movement, the action b; It passes through the outer peripheral surface and easily slides into the compression chamber. In other words, the low-pressure operating 'tAL body can be easily sucked in from the crank chamber side without installing a suction valve above the compression chamber.

This allows for screws to be removed during forward movement.・Completely prevents leakage of working fluid from the cylinder part, and conversely allows working fluid to pass through very easily during double movement.

[Example] The details of the present invention will be explained in detail based on the example shown in the drawings.

A screw with the abutment shape shown in Figure 1! - ring 3 is attached to ring iM 1G of piston l as shown in FIG. 3, and slides on the inner wall surface of cylinder 7.

The abutment end 31 on the - side of the screw 1 ring 3 is connected to the sliding surface 3.
A recess 3 is provided at the corner where 2 and the lower surface, that is, the forward contact surface 33 intersect.
4 is formed. The sliding surface 32 is a surface that slides on the inner wall surface of the cylinder 7, and the forward contact surface 33 is a surface that comes into close contact with the lower surface of the ring 'tM I G during forward movement of the piston 1, for example, during compression. In the example shown in FIG. 1, the recess 34 meets the sliding surface 32 and the sliding contact surface 33.
It is formed as a triangular prism-shaped notch opening to the surface.

The other abutment 1 part 35 of the piston ring 3 is connected to the above-mentioned -.
One fitting b: 1; fit exactly 1 into the recess 34 of the portion 31; fl the convex portion 3G, which is shaped like a triangular prism, for example.

When the piston ring 3 is installed in the ring groove 16, a lecturer 37 that penetrates in the width direction is formed between the end surface of the abutment end 31 and the opposing surface of the abutment end 35, and the gap between the end surface of the abutment end 35 and the abutment A partial iM portion 38 is formed in the width direction between the end portion 31 and the opposing surface of the recess 34 .

As shown in FIG. 2, a plurality of radial grooves 40, for example three at 90 degree intervals, are formed on the reciprocating contact surfaces 39 of the screws 1 to ring 3 facing the compression chamber, and the iM'10 is It penetrates from the inner peripheral surface of the ring 3 to the outer peripheral surface.

The tension ring 17 is AZ'd so as to come into contact with the inner peripheral surface of the piston ring 3, and presses the piston ring 3 against the inner wall surface of the cylinder 7. In FIG. 2, the abutment of the screw I/cylinder 3 and the abutment of the tension ring 17 are arranged at positions shifted by 180 degrees, but the invention is not limited to this.

In FIG. 3, when the piston 1 moves forward, that is, when it enters the compression stroke, the working fluid in the compression chamber 4 flows between the backward YZ surface 39, which is the side surface of the piston ring 3 on the compression chamber side, and the ring groove. 16 through the gap 18 formed between the upper surface of the piston ring 3 and the tension ring 17 and the radial groove 40, the seal 2. The sealing device is guided to the rear side of the cylinder, and thus pushes the piston ring 3 outward and presses it against the inner wall surface of the cylinder 7. At this time, the special abutment shape shown in FIG. 1 allows complete airtightness without leakage of working fluid from the abutment end.

In the suction stroke of the piston l shown in FIG.
is the pressure 1ii' of the piston ring 3 due to the frictional force between the inner wall surface of the cylinder 7 and the outer peripheral surface of the screw I/cylinder 3.
The return contact surface 39 which is the (lQI surface) on the i-chamber side is the ring i!
41 One concubine on the top surface of G, forward contact surface 33 and ring i! 4
A gap is formed between the lower surface of 1G and the lower surface of 1G. When the piston 1 moves backwards, for example during suction movement, the operation from the low pressure chamber 19/HIM
Although the screw 1 ring 3 is in close contact with the upper surface of the ring iM I G on the compression chamber side, the radial ii
440 and flows into the compression chamber 4 side very easily.

In other words, the suction valve is not installed at the top of the compression chamber (but low-pressure operation can be easily performed from the crank chamber side).

The 18 moving surfaces of piston ring j3 are worn ↓ [and the joint is jl:
Even if the distances 37 and 38 are enlarged, the abutment structure of the present invention maintains the performance of the first 1/1 while the convex part at the end of the abutment and the four parts overlap (n does not occur at all). Stable improvements were made in 11 days.

As a curved embodiment of the present invention, the J-
11. In contrast to the n-shaped cross-section shown in Fig. 3, it is possible to use a deformed tension ring 17' formed by either a spring or a coil spring with a round cross-section, and also a piston ring. 3rd ring 1st ring
The river support recess 41 can be formed as shown in FIG.

The shape of the concave portion 34 and convex portion 36 at the abutment end of the piston ring 3 has been changed from the triangular prism shape shown in FIG. 1 to a square prism convex portion 36' as shown in FIG. It is also possible to form the square columnar convex portion 36#.

By changing the shape and size of the portion 114 as appropriate, the flow of the working fluid in the vortex portion can be changed.

〔effect〕

According to the present invention, a reciprocating seal device has been obtained which completely prevents leakage of working fluid from the piston ring portion during forward movement, and allows working fluid to pass through very easily during backward movement.

As mentioned above, the piston ring according to the present invention can be used not only as a seal between the outer circumferential surface of the piston ring and the inner wall surface of the cylinder, but also as a shaft seal. The loss of iI■ that penetrates and the cross-sectional area of that groove! By adjusting the JXI, the frictional force acting on the 774 surface can be changed. In other words, the tensile force and suction pressure of the piston during the suction stroke are J, and the adjustment is iJ.
It becomes li.

[Brief explanation of drawings]

FIG. 1 is a partial perspective view of the abutment part of the piston ring of the seal device of the present invention, FIG. 2 is a plan view of the seal device of the present invention, and FIGS. Partial sectional view for explanation of compression stroke and suction stroke, 5th...
FIG. 8 shows an embodiment of the ribs of the sealing device of the present invention. ] The figure is a sectional view of a conventional compressor of 1117 construction. l... bis!・N4... Pressing chamber 1G... Ring groove 32... 111 Circular surface 34... Four parts 3G... Convex part 38... 1111 Part 3... Piston ring 7... Schilling - 31... Abutment ◇: 1: Part 33... Forward movement 71 face 35... Abutment end 37... Vortex part 40... Radial groove Agent Patent attorney Hideaki Kuwahara Figure 6 Figure 8

Claims (3)

[Claims] (1) It has a piston ring and a tension ring that is in contact with a circumferential surface opposite to the sliding surface of the piston ring so as to press the piston ring against the sliding surface, and the tension ring is attached to one abutment end of the piston ring. In this case, a concave portion that opens to the sliding surface, the forward contact side surface, and the abutment end surface is formed at the corner where the sliding surface and the forward contact side surface intersect, and the other abutment end is provided with a concave portion that is open to the abutment end surface of the one A convex portion is formed that fits perfectly into the concave portion of the abutment end, and penetrates from the inner circumferential surface to the outer circumferential surface of the piston ring on one side of the piston ring, which can fit closely to the side surface of the ring groove in which the piston ring is installed. Equipped with a backflow mechanism for reciprocating machines that has multiple grooves and completely prevents working fluid from leaking from the piston ring during forward movement, while allowing working fluid to pass through during backward movement. sealing device. (2) The sealing device with a backflow mechanism according to claim 1, wherein the convex portion has a columnar cross-sectional shape having a triangular, circular arc, or rectangular shape. (3) The seal device with a backflow mechanism according to claim 1 or 2, wherein the tension ring is formed of a flat spring with a rectangular cross section, a spring with a round cross section, or a coil spring.