JP2000054961A - Inlet valve device for compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noise by restraining suction pulsation. SOLUTION: Because a suction hole 32 connected with each compression chamber 8 is opened, an inlet valve for opening and closing the each suction hole 32 via a tongue-shaped reed 34a has a tightly connected seat surface 4a, and one whole impulse/contact region S of mutual impulse/contact surfaces between the tongue-shaped reed 34a and the seat surface 4a is roughened, suction pulsation based on a valve opening resistance is noticeably reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a suction valve device for a compressor, and more particularly, to a suction valve device having a suction pulsation reducing structure.

[0002]

2. Description of the Related Art In general, in a piston type compressor represented by a swash plate type compressor, a cylinder block having a bore, a valve plate provided with a suction hole and a discharge hole corresponding to the bore, a suction chamber and A housing defining a discharge chamber, and sandwiching the valve plate provided with a suction valve and a discharge valve to close the outer end of the cylinder block. A member for regulating the degree of opening of the tongue-shaped reed on the peripheral wall of the top end of the bore so as to maintain the closed posture close to the valve seat surface and the open posture separated from the valve seat surface by a predetermined distance so as to be repeatedly displaceable. A stop is provided. The above-mentioned valve seat surface is generally finished in an extremely smooth state with a surface roughness of about 2 to 3 μmRz due to the tight sealing with the suction valve and the joint sealing required for the extending surface.

[0003]

The refrigerant gas flowing in the compressor contains a fine lubricating oil component, and both the valve seat surface and the suction valve are placed in an environment where the oil component adheres. ing. And, as described above, since the valve seat surface is extremely smooth, the tongue-shaped lead of the suction valve is bent, and when the valve is opened, mainly the oil component interposed in the sealing area on the valve seat surface. Due to the surface tension, the tongue reed is brought into close contact with the valve seat surface.

Accordingly, the tongue-shaped reed resists the valve opening until the negative pressure in the compression chamber overcomes the surface tension added to the predetermined valve opening pressure, and at the same time as the valve opens, the refrigerant gas is rapidly introduced into the compression chamber. You. As a result, the instantaneous fluctuating pressure wave, that is, the suction pulsation induces abnormal noise of the evaporator, and the impact vibration wave of the tongue-shaped lead colliding with the above-mentioned locking portion is also compounded therewith, thereby promoting vehicle noise. Becomes

When the compressor is a swash plate type variable displacement compressor, the compressor is provided with a spring for biasing the swash plate so as to reduce the inclination angle when the operation is stopped, as a measure to alleviate the shock at the time of restart. . Therefore, when the electromagnetic clutch is turned off during operation in the maximum capacity state, the swash plate tends to shift from the maximum inclination angle to the minimum inclination angle by the biasing force of the spring. Immediately after the compressor stops, the pressure in each compression chamber corresponding to each piston is different, and each compression chamber exists in a completely independent form, so that the swash plate shifts to the minimum inclination angle by the biasing force of the spring. It will take a long time. As a result, when the compressor is stopped and restarted within a short time, there is a problem that the swash plate is activated while maintaining a considerably large inclination angle, and the starting shock cannot be alleviated.

A first problem to be solved by the present invention is to reduce the opening resistance of the tongue-shaped lead, thereby suppressing the suction pulsation and reducing the noise. The purpose is to reduce the shock at the time of starting and extend the life of the electromagnetic clutch and the engine.

[0007]

According to the first aspect of the present invention, there is provided a suction valve device for a compressor, wherein a suction hole connected to each compression chamber is opened, and each of the compression chambers is opened via a tongue-shaped lead. A suction valve that opens and closes a suction hole has a tightly closed valve seat surface,
It is characterized in that one of the contact surfaces between the tongue-shaped lead and the valve seat surface is roughened.

That is, the reduction of the suction pulsation is not sufficient by the conventional surface roughening treatment only on the limited area around the suction hole on the valve seat surface. By expanding to the entire contact area with the reed, the effect of reducing the suction pulsation is remarkably improved, so that the abnormal noise (noise) in the vehicle compartment is effectively eliminated. Of course, such a roughening process is not limited to the valve seat surface, and it is also possible to apply the roughening process to the entire contact area of the tongue-shaped lead itself that repeats bending with respect to the valve seat surface.

According to the second aspect of the present invention, a long hole extending along the center line is formed in each tongue-shaped lead to reduce the substantial contact area of the tongue-shaped lead with the valve seat surface. With this design, the bending rigidity of the tongue-shaped lead can be reduced without deteriorating the torsional rigidity as well as merely relaxing the valve opening resistance. This also promotes quick valve opening and suppresses self-excited vibration. Is done. In addition, if such a long hole is formed so as to include a discharge hole opened in the valve seat surface as in the third aspect of the invention, it simultaneously functions as a through hole through which the refrigerant discharged from the compression chamber flows. It is very advantageous in terms of both properties and aspects.

However, during the compression stroke of the piston, a small amount of refrigerant gas leaks into the suction chamber through the surface roughening region.
The surface roughness of the roughened region is desirably 15 to 30 μmRz. Further, a compressor applied as in the fifth aspect of the present invention includes a swash plate supported so as to be tiltable with respect to a drive shaft, and a piston engaged with the swash plate and reciprocating in each bore. A variable displacement compressor provided with a biasing means for returning the swash plate to the minimum tilt angle when the operation is stopped, the compressor is stopped and the tongue-shaped reed remains in contact with the valve seat surface. However, since the pressure release from the compression chamber to the suction chamber is started immediately through the minute gap created by the surface roughening, the swash plate can return to the minimum inclination more quickly, even if it is restarted early. On the other hand, the shock-reducing function can be sufficiently exhibited.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a swash plate type variable displacement compressor will be described below with reference to the drawings.
In FIG. 1, reference numeral 1 denotes a cylinder block. The front end of the cylinder block 1 is closed by a front housing 2 and the rear end of the cylinder block 1 is closed by a rear housing 3 via a valve plate 4. Bolt 2
They are fastened together by 1. A drive shaft 6 extending in the axial direction is accommodated in a crank chamber 5 formed by the cylinder block 1 and the front housing 2, and is rotatably supported by radial bearings 7a and 7b. The front end of the drive shaft 6 is connected to an automobile engine via, for example, an electromagnetic clutch and a transmission mechanism (not shown). The cylinder block 1 is provided with a plurality of bores 8 at positions surrounding the drive shaft 6, and each of the bores 8 is fitted with a single-headed piston 9 so as to reciprocate. 7c is a shaft sealing device.

In the crank chamber 5, a rotor 10 is rotatably coupled to the drive shaft 6 via a radial bearing 11 between the rotor 10 and the front housing 2, and a swash plate 12 is fitted behind the rotor 10. ing. And the swash plate 12
Is always urged rearward by a pressing spring 13 interposed between the rotor and the rotor 10. The swash plate 12 has smooth sliding surfaces 12a formed on the outer peripheral sides of both end surfaces, and hemispherical shoes 14, 14 are in contact with the sliding surface 12a. The single-headed piston 9 is engaged with the concave spherical surface.

A pair of brackets 12b, 12b are provided on the rotor 10 side of the inner area from the sliding surface 12a of the swash plate 12.
Projecting from the top dead center position T of the swash plate 12, the base ends of the guide pins 12 c, 12 c are fixed to the brackets 12 b, 12 b, and the guide pins 12 c, 12 c
Spherical portions 12d, 12d are formed at the tip of c.
Thus, in this compressor, a part of the hinge mechanism K is constituted by the brackets 12b, 12b, the guide pins 12c, 12c, and the spherical portions 12d, 12d.

In the center of the swash plate 12, a bent through hole 20 is provided on the drive shaft 6 to allow the swash plate 12 to be tilted. On the 10 side, it extends radially outward from the axis of the drive shaft 6,
And the sliding surface 12 while avoiding the shoe 14 on the rotor 10 side.
The counter weight 15 covering a is mounted by a rivet or the like. The swash plate 12 has its front end face 12e closer to the center than the counter weight 15 abuts on the rear end face 10a of the rotor 10, thereby restricting the maximum inclination angle. The minimum inclination is regulated by the contact.

A pair of support arms 17, 17 constituting the remaining portion of the hinge mechanism K are projected from the upper part of the rotor 10 rearward in the axial direction so as to align with the guide pins 12c, 12c. At the tip of 17, 17,
Guide holes 17a, 17a penetrate in parallel with a plane determined by the axis of the drive shaft 6 and the top dead center position T of the swash plate 12 and approach the axis of the drive shaft 6 from outside. Have been.
The orientation of the guide holes 17a, 17a is set so that the top dead center position of the piston 9 is kept immovable regardless of the inclination displacement of the swash plate 12, and the guide holes 17a, 17a
Inside the sphere portion 1 of the guide pins 12c, 12c, respectively.
2d and 12d are slidably inserted.

A suction chamber 30 and a discharge chamber 31 are defined in the rear housing 3, and a suction hole 32 and a discharge hole 33 corresponding to the bore 8 are opened in the valve plate 4. A compression chamber formed between the piston 9 and the piston 9 communicates with the suction chamber 30 and the discharge chamber 31 via the suction hole 32 and the discharge hole 33. The valve plate 4 has suction holes 32 and discharge holes 33.
A suction valve 34 and a discharge valve 35, which open and close, are mounted. Reference numeral 36 denotes a throttled bleed passage that communicates the crank chamber 5 with the suction pressure area (suction chamber) 30.

Now, the shape of the suction valve 34 and the surface treatment of the valve seat surface 4a where the suction valve 34 is tightly fitted will be described based on the embodiment shown in FIGS. FIG. 2 is a side view showing the suction valve 34 made of a thin plate material. In FIG. 2, positioning holes, bolt holes, and the like that are not directly related to the present invention are omitted. FIG. 3 is an enlarged cross-sectional view of a main part showing a relationship between the bent tongue-shaped lead 34a, the bore 8, and the valve seat surface 4a. FIG. 4 is a roughened state of the valve seat surface 4a corresponding to FIG. FIG.

In the figure, the valve seat surface 4a of the valve plate 4 is not only tightly fitted to the suction valve 34, but also its extending surface is clamped by the rear housing 3 to the outer end surface of the cylinder block 1. The surface roughness is 2-3 μm in consideration of sealing property
It is finished to an extremely smooth state of about Rz. The valve plate 4 is provided with a suction hole 32 and a discharge hole 33 that communicate with the respective bores 8 according to the number of cylinders. Suction hole 32
Valve 34 disposed on the valve seat surface 4a for opening and closing the valve
Each of the tongue-shaped leads 34a is formed by a punched U-shaped hole P. The similarly punched slot Q extending from the base along the center line X is formed so as to include the discharge hole 33 so as not to hinder the discharge of the compressed refrigerant gas. The valve seat surface 4a has an entire contact area with the tongue-shaped lead 34a that is bent, and is 15 to 30.
The roughened area S is roughened to μmRz and is divided and displayed by fine dots in FIG. Processing methods such as shot blasting, grinding, and knurling can be used for the surface roughening. For example, in the case of shot blasting, unnecessary portions can be masked.

As described above, in the present embodiment, the tongue-shaped lead 34
The entire contact area on the valve seat surface 4a that comes into contact with and separates from the valve seat surface 4a through the bending of the curve a is roughened (S). The surface tension (valve opening resistance) of the lubricating oil interposed in the contact area is significantly reduced, for example, as compared with the case where the roughening treatment is performed only around the limited opening of the suction hole 32. Particularly, as in the present embodiment, in the case where the elongated hole Q including the discharge hole 33 is formed along the center line X of the tongue-shaped lead 34a, the original through-hole function for flowing the refrigerant gas discharged from the compression chamber is provided. In addition to the valve seat surface 4a
By reducing the contact area of the tongue-shaped lead 34a with respect to the above, the valve opening resistance can be reduced rationally. Moreover, since the long hole Q can reduce the bending rigidity without lowering the torsional rigidity, quick opening of the valve is promoted and self-excited vibration is effectively suppressed.

That is, the magnitude of the suction pulsation caused by the valve opening resistance of the tongue-shaped lead 34a is determined by the area of the roughened surface as shown in the experimental results shown in FIG. It has been confirmed that, as it extends from the area where it comes into contact with the tip (around the opening of the suction hole 32) to the entire area where it comes into contact with the bending base of the tongue-shaped lead 34a, it tends to decrease proportionally. Was.

Therefore, an abnormal sound of the evaporator induced by suction pulsation accompanied by an instantaneous fluctuating pressure wave, and a collision vibration between the locking portion 8a notched on the peripheral wall of the top end of the bore 8 and the tongue-shaped lead 34a. The waves are well damped and the noise is well calmed. However, during the compression stroke of the piston 17, the roughened region S
Since a small amount of refrigerant gas leaks into the suction chamber 30 via the valve, care must be taken to increase the surface roughness of the roughened region S beyond a required range, in order to obtain a reduction in valve opening resistance. .

FIG. 5 shows another embodiment of the present invention. In this embodiment, the entire contact (flexure) area S 'of the tongue-shaped lead 34a itself which contacts the valve seat surface 4a instead of the valve seat surface 4a. Is roughened with the same surface roughness (15 to 30 μm Rz). That is, which of the mutual contact surfaces of the valve seat surface 4a and the tongue-shaped lead 34a is roughened is selected in consideration of the type and productivity of the surface treatment technology. Since there is no significant difference from the previous embodiment in the relaxation characteristics of, the overlapping description will be omitted.

Next, the function when the present invention is applied to the swash plate type variable displacement compressor shown in FIG. 1 will be described. As described at the outset, the compressor includes a swash plate 12 supported so as to be tiltable with respect to the drive shaft 6, a piston 9 engaged with the swash plate 12, and reciprocating in each bore 8. As a measure to alleviate the shock at the time of startup, a pressure spring 13 is provided which urges the swash plate 12 in a direction to reduce the inclination angle when the operation is stopped. Therefore, when the electromagnetic clutch is turned off during operation in the maximum capacity state, the swash plate 12 tends to shift from the maximum inclination angle to the minimum inclination angle by the urging force of the pressing spring 13. Bore (compression chamber) corresponding to each piston 9 immediately after the compressor stops.
Since the pressure in each of the compression chambers 8 is different and each compression chamber 8 exists in a completely independent form, it takes a long time until the biasing force of the pressing spring 13 causes the swash plate 12 to shift to the minimum inclination angle. . That is, if the compressor is restarted within a short time after the compressor is stopped, the swash plate 12 is activated while maintaining a considerably large inclination angle, and in addition to the deterioration of the feeling due to the startup shock, the swash plate 12 includes the clutch. The shock is transmitted to the drive system.

However, in the present suction valve device, one of the contact surfaces S (S ') of the tongue-shaped lead 34a and the valve seat surface 4a is 15 to 30 μm Rz.
It has been roughened. For this reason, the compressor is stopped,
Even when the tongue-shaped lead 34a remains in contact with the valve seat surface 4a, the pressure release from the compression chamber to the suction chamber 30 is immediately started via the fine gap generated by the roughening,
The swash plate 12 is quickly returned to the minimum inclination angle.

[0025]

As described above in detail, according to the first aspect of the present invention, the suction holes connected to the respective compression chambers are opened, and the suction valves for opening and closing the respective suction holes via the tongue-shaped reed are closed. The tongue lead and the contact surface between the valve seat surfaces are roughened in any one of the contact surfaces. The suction pulsation based on the valve opening resistance is significantly reduced, and the unusual noise (noise) in the vehicle interior is effectively eliminated. In addition, there is an effect that the omission muffler can be omitted. According to the second aspect of the present invention, each of the tongue-shaped leads is formed with a long hole extending along the center line to reduce a substantial contact area of the tongue-shaped lead with respect to the valve seat surface. In this case, the bending rigidity of the tongue-shaped lead is reduced without deteriorating the torsional rigidity as well as merely relaxing the valve opening resistance. Therefore, quick valve opening is promoted from this point, and self-excited vibration is suppressed. Further, when the compressor to be applied is a variable displacement compressor provided with a biasing means for returning the swash plate element to the minimum inclination angle in the operation stop state, the operation of the compressor is stopped. Later, even in the early restart, the shock mitigation function can be sufficiently exhibited.

[Brief description of the drawings]

FIG. 1 is a sectional view of a swash plate type variable displacement compressor to which the present invention is applied.

FIG. 2 is a side view showing a suction valve according to the present invention.

FIG. 3 is an enlarged sectional view of a main part showing a bent tongue-shaped lead and a valve seat surface.

FIG. 4 is an explanatory view showing a roughened form of a valve seat surface.

FIG. 5 is an explanatory view showing a roughened form of a tongue-shaped lead.

FIG. 6 is a graph showing a relationship between a roughened region and suction pulsation.

[Explanation of symbols]

4 is a valve plate, 4a is a valve seat surface, 8 is a bore (compression chamber), 9 is a piston, 12 is a swash plate, 13 is a pressing spring, 30 is a suction chamber,
32 is a suction hole, 34 is a suction valve, 34a is a tongue-shaped lead,
S and S 'are roughened areas

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeshi Kawada 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside the Toyota Industries Corporation (72) Inventor Tetsushi Komura 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Shares Inside Toyota Industries Corporation

Claims (5)

[Claims] A suction hole connected to each compression chamber is opened, and a suction valve for opening and closing each suction hole through a tongue-shaped lead is provided on a valve seat surface. A suction valve device for a compressor, wherein at least one of the contact surfaces between the valve seat surfaces is roughened. 2. The apparatus according to claim 1, wherein each of said tongue-shaped leads has an elongated hole extending along a center line. 3. A discharge hole connected to each compression chamber is opened on the valve seat surface, and a long hole of the tongue-shaped lead is formed to include the discharge hole. The described device. 4. The surface roughness of the roughened region is 15 to 30.
The device according to claim 1, 2 or 3, wherein the device has a μmRz. 5. The compressor according to claim 1, further comprising a swash plate supported so as to be displaceable at an angle with respect to a drive shaft, a piston engaged with the swash plate and reciprocating in each bore. 5. The apparatus according to claim 1, wherein the compressor is a variable displacement compressor having a biasing means for returning the pressure to a minimum inclination angle.