JP3248236U - Reed valve - Google Patents

Abstract

A reed valve capable of reducing noise by reducing the amplitude of the reed valve and suppressing unnecessary vibration.
[Solution] The reed valves have a valve base 3 disposed at one end of the cylinder chamber 2a, and are reed valves 10, 11 which open and close communication holes 8, 9 formed in this valve base 3, the communication holes 8, 9 being formed in an arc shape concentric with the cylinder chamber 2a, and the reed valves 10, 11 are formed into a roughly sector shape with through holes 10d, 11d on the inside, comprising arc-shaped portions 10a, 11a made of an elastic thin plate which close the communication holes 8, 9 formed at the tip side, two-sided arm portions 10b, 11b having one end connected to both the left and right sides of the arc portions 10a, 11a, and fixed portions 10c, 11c connecting the base ends of the arm portions.
[Selected Figure] Figure 1

Description

The present invention relates to a reed valve used in gas compressors such as compressors and vacuum pumps to open and close the discharge or suction port.

Generally, a positive displacement compressor or vacuum pump is provided with a cylinder chamber in which the pressure of the gas inside is changed cyclically, and the gas is sucked in or discharged from the suction port and discharge port provided in the cylinder chamber by repeating a suction process in which the internal pressure is lowered and a compression process in which the pressure is increased. Normally, a reed valve is provided at the suction port and discharge port to prevent backflow of the gas, and in the process of discharging the gas compressed by the cylinder chamber, the discharge valve opens to discharge the compressed gas from the cylinder chamber, while the suction valve is closed to close the suction port flow path to prevent backflow, and the flow direction of the gas is restricted to one direction.

However, when gas is sucked in or discharged, a large force acts on the reed valve in a direction that opens the suction port or discharge port, causing the reed valve to deform significantly and not return to its original shape, resulting in a problem that it becomes impossible to close the suction port, etc. To solve this problem, as disclosed in, for example, Japanese Utility Model Laid-Open Publication No. 61-171882 (Patent Document 1) and Japanese Patent Laid-Open Publication No. 2004-360542 (Patent Document 2), a stopper member has conventionally been provided to suppress deformation of the reed valve in the opening direction, thereby suppressing excessive deformation of the reed valve.

Utility Model Publication No. 61-171882 JP 2004-360542 A

The reed valves shown in Patent Documents 1 and 2 can suppress excessive deformation of the reed valve in the opening direction by providing a stopper member, but when the gas inflow speed is high and a large force acts on the reed valve, or when the reed valve opens and closes at high speed, the reed valve hits the stopper member with force when opening and hits the seat of the opening hole with force when closing, causing noise (banging sound). Also, when the cyclic pressure change in the cylinder chamber exceeds 1,000 strokes per minute, the reed valve cannot follow this high-speed change due to inertia, so it may not be able to close either the intake port or the discharge port provided in the cylinder chamber. As a result, the gas flows back and the reed valve vibrates due to the increase in pressure in the cylinder chamber, causing pulsating flow, causing a problem of intense noise.

SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a reed valve capable of reducing noise by reducing the amplitude of the reed valve and suppressing unnecessary vibration.

In order to solve the above problems, the reed valve of the present invention has a valve base disposed at one end of a cylinder chamber, and opens and closes a communication hole formed in this valve base, the communication hole being formed in an arc shape concentric with the cylinder, and the reed valve is formed into a roughly fan shape with a through hole on the inside, comprising an arc-shaped portion formed at the tip end of a resilient thin plate that closes the communication hole, two arm portions having one end connected to each of the left and right sides of the arc portion, and a fixed portion connecting the base ends of the arm portions.

In addition, a pressure valve made of an elastic thin plate is superimposed on the upper surface of the reed valve, and the pressure valve is formed into a roughly sector shape with a through hole on the inside, with an arc portion and two arm portions of roughly the same shape as the reed valve, and a fixed portion connecting the base ends of the arms, and the tip of the arc portion is curved so as to abut the arc portion of the reed valve.

According to the reed valve of the present invention, the communication hole through which the intake or discharge gas flows is formed in an arc shape, so compared to conventional general round holes, the opening area of the communication hole, which is calculated by multiplying the circumference of the intake and discharge ports by the amount of deflection of the reed valve, is larger, and the area through which gas flows due to pressure changes in the cylinder chamber is enlarged, so the amount of deflection of the reed valve that opens and closes the communication hole can be reduced.
Even when the reed valve opens and closes the communication hole at high speed, the impact of the reed valve hitting the opening of the communication hole is reduced, so noise (banging sounds) can be significantly reduced. Also, because the amount of deflection of the reed valve is small, the reed valve follows even if the pressure in the cylinder chamber changes at high speed, so the backflow of gas is suppressed, reducing noise.

In addition, the reed valve has an arc-shaped portion formed at the tip, two arms connected to the left and right sides of the arc, and a fixed portion connecting the base ends of the arms, which form a through hole on the inside, so that gas flowing through the communication hole flows from both the through holes on the outer periphery and inner periphery of the arc, allowing the gas being sucked in or discharged to flow quickly around the arc, thereby preventing excessive deformation and vibration of the reed valve and reducing noise.

Furthermore, by overlapping the pressurizing valve on the upper surface of the reed valve, the pressurizing valve suppresses the inherent vibrations that occur in addition to the reed valve opening and closing the communication hole, allowing the reed valve to perform its original and proper opening and closing operations. That is, since the reed valve is formed of an elastic thin plate, after the opening and closing operation, a damping vibration with a gradually decreasing amplitude occurs as a spring. Therefore, if the reed valve performs an opening and closing operation at high speed, the next opening and closing operation is performed while the damping vibration is occurring, which can cause malfunctions such as backflow. By overlapping the pressurizing valve on the upper surface of the reed valve, the damping vibration is quickly reduced, and malfunctions can be reduced. In addition, since the tip of the pressurizing valve is curved so as to abut against the arc portion of the reed valve, the overlapping does not hinder the original operation of the reed valve. Furthermore, since a through hole is formed in the area surrounded by the arc portion of the pressurizing valve and the arm portions on two sides, the gas flowing through the communication hole flows from both the through holes on the outer periphery side and the inner periphery side of the arc portion, and the gas to be sucked or discharged can be quickly circulated around the arc portion.

1 is a cross-sectional view showing a compressor equipped with a reed valve according to the present invention. 4 is a plan view showing a reed valve that closes the suction communication hole and the discharge communication hole. FIG. FIG. 4 is a plan view showing a discharge reed valve that closes the discharge communication hole. 4 is a plan view showing a suction reed valve that closes the suction communication hole. FIG. FIG. 4 is a cross-sectional view showing a state during ejection. 11 is an explanatory diagram showing the operation of opening and closing a discharge communication hole by a discharge reed valve. FIG. FIG. 4 is a cross-sectional view showing a reed valve with a pressurizing valve overlapped therewith. FIG. 4 is an exploded perspective view showing a pressure valve overlapping with a reed valve. FIG. 4 is a front view showing a state in which gas is circulated through the discharge reed valve and the pressurizing valve.

The reed valve of this invention has a valve base disposed at one end of a cylinder chamber, and opens and closes a communication hole formed in this valve base, the communication hole being formed in an arc shape concentric with the cylinder, and the reed valve is formed into a roughly fan shape with a through hole on the inside, comprising an arc-shaped portion formed at the tip end of a resilient thin plate that closes the communication hole, two arm portions having one end connected to each of the left and right sides of the arc portion, and a fixed portion connecting the base ends of the arm portions.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 shows a compressor as an example of a gas compressor equipped with a reed valve according to the present invention. Compressor 1 is similar to a well-known compressor, and includes a cylinder portion 2, a valve base 3, a suction chamber 4, a discharge chamber 5, a suction port 6, and a discharge port 7. Suction reed valve 10 and discharge reed valve 11 are provided in suction communication hole 8 and discharge communication hole 9 formed in valve base 3.

The cylinder section 2 has a cylindrical cylinder chamber 2a, in which a piston 12 reciprocates up and down in the cylinder chamber 2a by a reciprocating drive source (not shown). A seal cup 12b is attached to the top surface of the piston 12 to prevent gas from leaking from the cylinder chamber 2a. A suction communication hole 8 and a discharge communication hole 9 are formed in a valve base 3 disposed at the upper end of the cylinder chamber 2a, and communicate with the cylinder chamber 2a. The suction communication hole 8 and the discharge communication hole 9 are further connected to a suction chamber 4 and a discharge chamber 5, which are respectively partitioned. A suction port 6 and a discharge port 7 are formed in the suction chamber 4 and the discharge chamber 5, which are connected to external equipment by a pipe or the like. The fluid pressure in the cylinder chamber 2 is changed by reciprocating the piston 12 in the cylinder chamber 2.

The suction communication hole 8 and discharge communication hole 9 formed in the valve base 3 are formed in an arc shape concentric with the cylindrical cylinder chamber 2a, as shown in Figure 2, and the opening angle is approximately 90 to 150 degrees from the center of the cylinder to maximize the opening area. Continuous straight portions are formed on both sides of the suction communication hole 8 and discharge communication hole 9, forming a roughly C-shape overall.

A suction reed valve 10 is provided in the suction communication hole 8, and a discharge reed valve 11 is provided in the discharge communication hole 9. The suction reed valve 10 and the discharge reed valve 11 have substantially the same structure, so the discharge reed valve 11 will be described first. The discharge reed valve 11 shown in Fig. 3 is formed from a thin plate made of elastic metal or plastic, and has an arc-shaped arc portion 11a at the tip end that closes the discharge communication hole 9, two arm portions 11b connected to the left and right sides of the arc portion 11a at one end, and a fixing portion 11c connected to the base end of the arm portion 11b. Furthermore, a through hole 11d is formed inside the area surrounded by the arm portion 11b and the side arm portion 11b, and the overall shape is approximately fan-shaped. The discharge reed valve 11 is attached to the upper surface of the valve base 3 by a screw 13 as shown in Fig. 1.

The other suction reed valve 10 has substantially the same structure as the discharge reed valve 11 described above in that it is disposed in the cylinder chamber 2a on the underside of the valve base 3, and is formed from a thin plate of elastic metal or plastic, and as shown in Figure 4, at its tip side there is an arc-shaped portion 10a that closes the suction hole 8, two arm portions 10b each having one end connected to the left and right sides of the arc portion 10a, and a fixed portion 10c connecting the base ends of the arm portions 10b, and further a through hole 10d is formed inside the area surrounded by the arm portion 10b and the two arm portions 10b, giving it a generally fan-shaped overall shape. The suction reed valve 10 is attached to the underside of the valve base 3 with a screw 13.

Next, the operation of the reed valve according to the present invention will be described. When the piston 12 in the cylinder chamber 2 is at bottom dead center LD as shown in Fig. 5, the suction reed valve 10 and the discharge reed valve 11 close the suction communication hole 8 and the discharge communication hole 9, respectively. When the piston 12 rises from bottom dead center LD to top dead center UD, the gas in the cylinder chamber 2a is pressurized, causing the discharge reed valve 11 to move from a state in which it closes the discharge communication hole 9 as shown in Fig. 6(A) to a state in which the arc portion 11a rises as shown in Fig. 6(B), discharging the gas in the cylinder chamber 2a into the discharge chamber 5. At this time, the suction reed valve 10 closes the suction communication hole 8 as shown in Fig. 5.

In this way, when gas is discharged, as described above, the discharge communication hole 9 is formed in an arc shape with a large opening area, so that the gas in the cylinder chamber 2a is quickly discharged. At this time, the discharge reed valve 11 has an inward through hole 11d formed by the arc-shaped arc portion 11a and the arm portions 11b on two sides, so that the gas shown by the dotted and solid lines is quickly discharged through the periphery of the arc portion 11a and the inward through hole 11d, as shown in Figure 6(B). When gas is quickly discharged in this way, the pressure of the gas is diffused, so that the amplitude H at which the arc portion 11a of the discharge reed valve 11 floats becomes smaller, as shown in Figure 6(B).

After this discharge stroke, while the piston 12 descends from top dead center UD to bottom dead center LD, the gas in the cylinder chamber 2a is decompressed, and the suction reed valve 10 opens the suction communication hole 8 to draw in the gas from the suction port 8. At this time, the discharge reed valve 11 closes the discharge communication hole 9. During this suction stroke, as with the discharge reed valve 11, an inward through hole 10d is formed by the arc-shaped arc portion 10a and the arm portions 10b on two sides, so that the gas is drawn in through the through hole 10d around and inward of the arc portion 10a, and therefore the gas is drawn in quickly, and the pressure of the gas is diffused, so that the amplitude of the floating of the arc portion 10a of the suction reed valve 10 can be reduced.

As described above, when gas is sucked in and discharged, the amplitude of the discharge reed valve 11 and the suction reed valve 10 rising can be reduced, so that even if the speed is changed at a high speed of 1,000 strokes per minute or more, the amplitude of each reed valve is small, so the impact of the reed valve hitting the opening of the communication hole is reduced, and the noise (smacking sound) is significantly reduced. Incidentally, in gas compressors such as well-known compressors, the communication hole is small and circular, so that as mentioned above, when the reed valve is greatly deformed and then closes the communication hole, it hits the communication hole and generates a loud noise (smacking sound). In contrast, the reed valve of the present invention has a circular communication hole with a large opening area and a reed valve with a through hole formed inward by the circular arc portion and the two arm portions 10b, 11b, which reduces the amplitude of the reed valve rising to less than half, thereby suppressing the noise (smacking sound) to about one-fourth or less.

8 shows another embodiment of the reed valve according to the present invention. The difference from the above-mentioned embodiment is that a pressure valve made of an elastic thin plate is superimposed on the upper surface of the reed valve. The pressure valves are the suction pressure valve 14 superimposed on the above-mentioned suction reed valve 10, and the discharge pressure valve 15 superimposed on the discharge reed valve 11, but both are the same, and only the discharge pressure valve 15 superimposed on the discharge reed valve 11 will be explained.

The discharge pressurizing valve 15 has almost the same shape and configuration as the discharge reed valve 11, is made of an elastic thin metal plate, and as shown in Fig. 9, has an arc-shaped arc portion 15a formed at the tip end, two arm portions 15b connected to the left and right sides of the arc portion 15a at one end, and a fixed portion 15c connected to the base end of the arm portion 15b. A through hole 15d is formed inside the area surrounded by the arc portion 15a and the arm portions 15b at the two sides, and the overall shape is approximately fan-shaped. Furthermore, as shown in Fig. 9, the discharge pressurizing valve 15 is curved as a whole with a bending line TL near the fixed portion 15c so that the tip of the arc portion 15a abuts against the arc portion 11a of the discharge reed valve 11. The discharge pressurizing valve 15 is attached to the upper surface of the valve base 3 with a screw 13 while overlapping the discharge reed valve 11.

Next, the operation of the discharge pressurizing valve 15 will be described. When the piston 12 in the cylinder chamber 2 is at bottom dead center LD as shown in Fig. 5, the discharge reed valve 11 closes the discharge communication hole 9. When the piston 12 rises from bottom dead center LD to top dead center UD, the gas in the cylinder chamber 2a is pressurized, causing the arc portion 11a of the discharge reed valve 11 to rise and discharge the gas in the cylinder chamber 2a into the discharge chamber 5. At this time, the arc portion 15a of the discharge pressurizing valve 15 also rises following the arc portion 11a of the discharge reed valve 11. Thereafter, when the suction stroke is started and the discharge reed valve 11 closes the discharge communication hole 9, the arc portion 15a of the discharge pressurizing valve 15 also follows the discharge reed valve 11.

When the gas in the cylinder chamber 2a is discharged, the discharge pressurizing valve 15 also has a through hole 15d formed inside surrounded by the arc portion 15a and the arm portions 15b on two sides, so that as shown in Figure 10, the gas shown by the dotted line is discharged through the through hole 15d in the same manner as the discharge path of the discharge reed valve 11. For this reason, even if the discharge pressurizing valve 15 is overlapped, the gas is quickly discharged, so that the amplitude H at which the discharge reed valve 11 floats can be reduced as shown in Figure 10.

When the piston 12 moves up and down at a high speed of 1,000 strokes or more per minute, the discharge reed valve 11 also vibrates at a high speed by opening and closing at the same stroke. Since the discharge reed valve 11 is made of an elastic thin plate, it generates a damping vibration after bending due to the opening and closing operation. This damping vibration may prevent the discharge communication hole 9 from being properly closed. This may cause malfunction such as backflow, which may cause loud noise. At this time, the discharge pressurizing valve 15 is superimposed on the upper surface of the discharge reed valve 11, so that the damping vibration can be quickly suppressed and the malfunction can be reduced, and as a result, the noise caused by the malfunction such as backflow can be reduced. The suction pressurizing valve 14 superimposed on the suction reed valve 10 has the same function as the above-mentioned discharge pressurizing valve 15, and a detailed description thereof will be omitted.

Although the present invention has been described above based on the embodiments, it goes without saying that the present invention is not limited to the above embodiments and can be modified in various ways without departing from the spirit and scope of the present invention. For example, the shape of the suction communication hole or the discharge communication hole and the shape of the suction reed valve or the discharge reed valve may be modified to correspond to a gas compressor such as a compressor or a vacuum pump.

1. Compressor (gas compressor)
2 Cylinder portion 2a Cylinder chamber 3 Valve base 6 Suction port 7 Discharge port 8 Suction communication hole 9 Discharge communication hole 10 Suction reed valve 10a Arc portion 10b Arm portion 10d Through hole 11 Discharge reed valve 11a Arc portion 11b Arm portion 11d Through hole 12 Piston 14 Suction pressure booster valve 14a Arc portion 14b Arm portion 14d Through hole 15 Discharge pressure booster valve 15a Arc portion 15b Arm portion 15d Through hole

Claims (2)

A valve base is disposed at one end of a cylinder chamber, and a reed valve opens and closes a communication hole formed in the valve base,
The communication hole is formed in an arc shape concentric with the cylinder,
The reed valve is formed into a roughly sector shape with a through hole on the inside, and is made of an elastic thin plate having an arc-shaped portion that closes the communicating hole formed at the tip side, two arm portions having one end connected to the left and right sides of the arc portion, and a fixing portion connecting the base ends of the arm portions. A pressure valve made of an elastic thin plate is superimposed on the upper surface of the reed valve,
2. The reed valve according to claim 1, wherein the pressurizing valve is formed into a generally sector shape having an inwardly through hole by means of an arc portion and two arm portions having substantially the same shape as the reed valve, and a fixing portion connecting the base ends of the arm portions, and the tip of the arc portion is curved so as to abut against the arc portion of the reed valve.

Images