JPH09112461A - Swing compressor - Google Patents

Abstract

(57) An object of the present invention is to provide a highly efficient swing compressor capable of suppressing the occurrence of a gap between a cylinder and a piston and suppressing fluid leakage from a high pressure chamber to a low pressure chamber. SOLUTION: A piston 9 is revolved in a cylinder chamber 6a with a swing bush 32 as a fulcrum via a blade 31 as the drive shaft rotates. An eccentric bush 11 is rotatably fitted in the shaft hole 9a of the piston. The eccentric bush and the drive shaft are rotatably connected by an eccentric pin 42 which is eccentric from the shaft center O1 of the drive shaft. The eccentric pin is located on the piston rotation direction side with respect to the axis k1 passing through the axis of the drive shaft and the axis O3 of the piston, and is an orthogonal line passing through the axis of the piston at right angles to the axis. The axis O2 is set on the opposite side of the axis of the drive shaft with respect to k2. Piston, cylinder
The eccentric pin is rotatably supported about the shaft center so that the amount of eccentricity with respect to 6 can be varied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swing compressor used in a refrigeration system or the like, and more particularly to measures for preventing fluid leakage between a piston and a cylinder provided in the cylinder.

[0002]

2. Description of the Related Art Conventionally, as a swing compressor, for example, as disclosed in Japanese Unexamined Patent Publication No. 6-147164, a cylinder having a cylinder chamber in which an intake port and a discharge port are opened, and both sides in the axial direction of the cylinder. A side housing arranged to close the cylinder chamber, and an annular piston that is arranged in the cylinder chamber and rotatably fits with the shaft center eccentric to the shaft center of the drive shaft,
A blade that is projectingly coupled to the outer peripheral portion of the piston and divides the cylinder chamber into a low pressure chamber that communicates with the suction port and a high pressure chamber that communicates with the discharge port, and a hole formed in the cylinder facing the cylinder chamber. And a swinging bush for swingably and reciprocally supporting the protruding tip side of the blade, with the swinging bush as a fulcrum via the blade as the drive shaft rotates. It is known that a piston is revolved in a cylinder chamber, and a fluid such as a refrigerant gas sucked from the suction port is compressed and discharged from the discharge port every time the piston revolves.

[0003]

However, in the above swing compressor, since the blade is connected to the outer peripheral portion of the piston, the weight of the blade is added to the weight of the piston so that the center of gravity of the piston is greater than the center of the piston. Since it is located on the blade side, a sufficient pressing force for pressing the piston against the inner peripheral surface of the cylinder chamber cannot be obtained due to the centrifugal force that acts when the piston revolves. On the other hand, in the final stage of the compression process in which the volume of the high pressure chamber is reduced to compress the fluid, the pressure difference between the high pressure chamber and the low pressure chamber increases, so the fluid in the high pressure chamber causes the outer peripheral surface of the piston to move toward the cylinder chamber. The force to separate it from the inner peripheral surface of the piston acts, and in combination with the insufficient pressing force due to the centrifugal force of the piston described above,
A gap may occur between the two surfaces, and leakage of the fluid in the high pressure chamber to the low pressure chamber through this gap may impair the efficiency of the swing compressor.

The present invention has been made in view of the above points, and an object thereof is to suppress the formation of a gap between a cylinder and a piston and to suppress fluid leakage from a high pressure chamber to a low pressure chamber. It is to provide a highly efficient swing compressor to obtain.

[0005]

[Means for Solving the Problems] In order to achieve the above-mentioned object, a solution means of the invention according to claim 1 is a suction port (2
1) and a cylinder (6) having a cylinder chamber (6a) where the discharge port (22) is open, a drive shaft (5) introduced into the cylinder chamber (6a), and the cylinder chamber (6a). An annular piston (9) which is arranged and rotatably fitted in a state where the axis (O3) is eccentric with respect to the axis (O1) of the drive shaft (5);
The cylinder chamber (6a) is connected to the outer periphery of (9) in a protruding manner.
A blade (31) for partitioning the air into a low pressure chamber (34) communicating with the suction port (21) and a high pressure chamber (35) communicating with the discharge port (22);
(6) is swingably provided in a hole (24) formed facing the cylinder chamber (6a), and swingably supports the protruding tip side of the blade (31) so as to be swingable and retractable. Dynamic Bush (32)
It is assumed that the swing compressor (1) is provided with the above-mentioned piston (9) and revolves in the cylinder chamber (6a) as the drive shaft (5) rotates. Furthermore, the piston
While the eccentric bush (11) is rotatably fitted in the shaft hole (9a) of (9), the eccentric bush (11) and the drive shaft (5) are connected to each other.
An eccentric pin (42), which is eccentric from the shaft center (O1) of (5), is rotatably connected. Then, install the eccentric pin (42) on the piston (9) with respect to the axis (k1) that passes through the axis (O1) of the drive shaft (5) and the axis (O3) of the piston (9). Located on the rotation side and orthogonal to the axis (k1), the axis (O3) of the piston (9)
The configuration is such that the shaft center (O2) is located on the side opposite to the shaft center (O1) position of the drive shaft (5) with respect to the orthogonal line (k2) passing through.

With this configuration, in the invention according to claim 1, as shown in FIG. 1, the high pressure chamber (35) is provided in the piston (9).
Fluid pressure (FG) from the drive shaft (5) acts on the eccentric bush (11), and both of these forces (FG) and (FT) are applied. The resultant force (FC) acts in the direction of eccentricity between the piston (9) and the cylinder (6). This resultant force
The outer peripheral surface of the piston (9) is pressed against the inner peripheral surface of the cylinder chamber (6a) by (FC), and a high pressure chamber (35) is suppressed by forming a gap between the both (9) and (6a). Fluid leakage from the low pressure chamber (34) is prevented. In addition, this resultant force (FC) causes the piston
Since the outer peripheral surface of (9) is pressed toward the cylinder (6) side (the inner peripheral surface side of the cylinder chamber (6a)), there is a processing error on the outer peripheral surface of the piston (9) and the inner peripheral surface of the cylinder chamber (6a). Even if there is a gap, it is possible to seal between both sides, and high processing accuracy is not required when manufacturing both (9) and (6a).

[0007] The solution taken by the invention of claim 2 is as follows.
In addition to the constituent features of the invention according to claim 1, a piston (9)
So that the amount of eccentricity with respect to the cylinder (6) is variable,
The eccentric pin (42) is rotatably supported about the shaft center (O2).

With this configuration, according to the second aspect of the invention, when the cylinder chamber (6a) is in a liquid compression state or foreign matter is mixed in the cylinder chamber (6a), the outer peripheral surface of the piston (9) is Can be separated from the inner peripheral surface of the cylinder chamber (6a) to avoid liquid and foreign matter, and the revolution movement of the piston (9) in the cylinder chamber (6a) can be maintained smoothly.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows the entire structure of the swing compressor according to the embodiment of the present invention. The swing compressor (1) is
A motor (3) is installed in the upper inner part of the closed casing (2), and a compression element (4) is installed on the lower side of the motor (3), and a drive shaft extending from the motor (3). The compression element (4) is driven to rotate at (5). This compression element (4) is a cylinder with a cylinder chamber (6a) inside.
(6) and a front head (7) which is disposed in contact with the upper and lower open portions of the cylinder (6) and closes the upper and lower open portions.
And a rear head (8) and a piston (9) rotatably arranged in the cylinder chamber (6a),
The lower part of the drive shaft (5) is bearing-supported by the bearings provided in (7) and (8).

Further, as shown in FIG. 1, the cylinder chamber
The inner peripheral wall of (6a) is formed in a substantially circular cross section, the piston (9) is formed in an annular shape having a shaft hole (9a) in the center, and the shaft hole (9a) has Drive shaft (5) is eccentric bush (11)
It is rotatably fitted through.

Further, the cylinder (6) has a suction port (21) and a discharge port (2) which are open to the outer peripheral wall of the cylinder chamber (6a).
2) is provided, and a suction pipe (not shown) is connected to the suction port (21) from the outside of the closed casing (2), while the discharge port (22) has a cylinder chamber (6a) (specifically, High pressure chamber (3
5)) The discharge valve (2
3) is provided. The discharge valve (23) includes a valve body (23a) that opens and closes the discharge port (22), and a valve retainer (23b) that restricts the opening of the valve body (23a) by a contact amount. Become. Further, the cylinder (6) has a cylindrical bush hole (24) penetrating axially at a position between the suction port (21) and each discharge port (22).
(Hole) is formed, and the bush hole (24) has an opening (24a) which is open to face the cylinder chamber (6a) in a part of the circumference.

The piston (9) is integrally provided with a blade (31) extending radially from the outer peripheral surface of the piston (9). The blade (31) is integrally formed with the piston (9), or is made of a separate member and is formed by connecting the two with a concavo-convex fitting structure or an adhesive or the like. The protruding tip side of the blade (31) is inserted into the bush hole (24), while the pair of swing bushes (32), (32) having a semicircular cross section in the bush hole (24). ) Is swingably arranged, and the swing bushes (32) and (32) are arranged such that the blade (31) is inserted into the bush hole (24) while sandwiching the protruding tip side of the blade (31). Allowing to move back and forth and blade
It is provided so as to swing together with the bush (31) in the bush hole (24). And the blade (31) is a cylinder (6)
Between the inner surface of the cylinder and the outer surface of the piston (9) (6
a) is divided into a low pressure chamber (34) communicating with the suction port (21) and a high pressure chamber (35) communicating with each discharge port (22).
(9) revolves along the outer peripheral wall of the cylinder chamber (6a) so that the split bush (32) swings via the blade (31) as a fulcrum, and suction is made from the suction port (21) at each revolution. A fluid such as a refrigerant gas is compressed and discharged from each discharge port (22). 2 (2a) is an external discharge pipe connected to the upper part of the closed casing (2).

The drive shaft (5) is arranged so that its lower end is introduced into the shaft hole (9a) of the piston (9). As shown in FIG. 3, a projecting piece (41) is provided on the lower end of the drive shaft (5) so as to project from the side surface of the drive shaft (5). The protruding piece (41) is formed by protruding in a plane crescent shape in one direction perpendicular to the side surface of the drive shaft (5), and its upper and lower surfaces are formed as horizontal surfaces. Furthermore, the protruding piece (41)
A small-diameter cylindrical eccentric pin (42) extending downward from the lower surface of the projecting piece (41) is projectingly provided on this. Therefore, the shaft center (O2) of this eccentric pin (42) is a predetermined distance from the shaft center (O1) of the drive shaft (5).
It is eccentric by (m). Further, the eccentric pin (42) is set at a position where its lower end does not interfere with the rear head (8).

The eccentric bush (11) has a flat plate-shaped main body (1) having a diameter substantially the same as the shaft hole (9a) of the piston (9).
1a), and a cylindrical projection (11b) having a shaft center on the same straight line as the shaft center (O1) of the drive shaft (5) is projected on the lower surface of the main body part (11a) when it is fitted. Has been done. Main body (11a)
Has an eccentric pin insertion hole (11c) that penetrates vertically.
Is eccentrically provided with respect to the protrusion (11b) with the same size as the eccentric amount (m) described above. This eccentric pin insertion hole (1
1c) has an inner diameter substantially the same as the outer diameter of the eccentric pin (42). Furthermore, the drive shaft (5) and the eccentric bush (11)
Means that the eccentric pin (42) of the drive shaft (5) is inserted into the eccentric pin insertion hole (11c) of the eccentric bush (11) and the axial center of the piston (9) is
(O3) is eccentrically connected to the shaft center (O2) of the drive shaft (5). That is, the eccentric bush (11) and the drive shaft (5) are rotatably connected to each other, and the piston (9) is eccentric so that the eccentric amount with respect to the cylinder (6) is variable, as shown in FIG. The pin (42) is supported rotatably around the axis (O2).

Also, as shown in FIG. 4, the axis (O2) of the eccentric pin (42) is the axis (O1) of the drive shaft (5) and the axis (O3) of the piston (9). The direction of rotation of the piston (9) (Fig.
Is located above the axis (k1) of the
Orthogonal line (k2) passing through the axis (O3) of the piston (9) orthogonal to 1)
On the other hand, it is set so as to be located on the side opposite to the axis (O1) of the drive shaft (5) (on the left side of the orthogonal line (k2) in FIG. 1). It should be noted that the one-dot chain line arrow in FIGS. 1 and 5 indicates the rotation direction of the eccentric bush (11).

Here, in order to explain the operation of the swing compressor (1), first, the motor (3) is started to drive the drive shaft.
With the rotation of (5), the piston (9) does not rotate, but revolves along the outer peripheral wall while contacting or approaching the inner peripheral surface of the cylinder chamber (6a) at one location on the outer peripheral surface thereof. Then, the fluid is sucked into the low pressure chamber (34) through the suction port (2a), and the low pressure chamber (34)
(34) moves to the high pressure chamber (35) as the piston (9) revolves, and the fluid compressed in the high pressure chamber (35) is discharged from the discharge port (35) into the closed casing (2). And is discharged to the external discharge pipe (2b) side.

Next, the force acting on the piston (9) and the eccentric pin (42) will be described with reference to FIGS. 1 and 4.

A fluid pressure (FG) acting on the piston (9) in a direction of restricting its rotation by the high pressure fluid on the high pressure chamber (35) side.
The (refrigerant gas pressure) and the rotational force (FT) that causes the drive shaft (5) to rotate the eccentric bush (11) via the eccentric pin (42) act. And, as the acting direction of these two forces, the fluid pressure (FG) is from the high pressure chamber (35) to the piston (9).
Acts toward the center of gravity (OG) of the blade (closer to the blade (31) than the center of axis (O3)). On the other hand, the rotational force (FT) acts in a direction from the shaft center (O3) of the piston (9) toward the shaft center (O2) of the eccentric pin (42). Thus, as shown in FIG. 4, the rotational force (FT) has a predetermined obtuse angle (θ) across the eccentric direction (axis center line (k1)) between the cylinder (6) and the piston (9). Existing and working. Therefore, the resultant force (FC) acts on the piston (9). Then, as can be seen from FIG. 4, the resultant force (FC) is due to the fact that the obtuse angle (θ) sandwiches the eccentric direction between the cylinder (6) and the piston (9), so that the rotational force (FT) is It is divided into a force in the direction of the axis (k1) and a direction perpendicular to the axis (k1), and the force in the direction of the axis (k1) causes the outer peripheral surface of the piston (9) to move to the cylinder chamber ( It will act as a force pressing against the inner peripheral surface of 6a). Further, as shown in FIG. 4, the resultant force (FC) is a straight line in the direction in which the rotational force (FT) acts, that is, the axis (O2) of the eccentric pin (42) and the axis (O3) of the piston (9). Let α be the angle formed by the straight line (k3) connecting with and the straight line in the direction in which the fluid pressure (FG) acts, that is, the straight line (K4) that passes through the center of gravity (OG) of the piston (9), then α Since the size of the fluid changes in proportion to the work of compressing the fluid, even if the pressure difference between the high and low pressures fluctuates, the pressing force (FC) that follows it can be obtained and the high pressure chamber (35) can be sealed. Become.

Therefore, in the above embodiment,
Eccentric pin (42) using fluid pressure (FG) and rotational force (FT)
By generating a resultant force (FC) of FG tan α on the eccentric bush (11) around the shaft center (O2) of the piston, the outer peripheral surface of the piston (9) is pressed against the inner peripheral surface of the cylinder chamber (6a), and the piston (9) By moving the center of gravity to the blade (31) side, even if the pressing force to the inner peripheral surface of the cylinder chamber (6a) due to the centrifugal force when the piston (9) revolves is insufficient, it will be sufficiently compensated. , The pressing force (FC) corresponding to the high and low differential pressure in the entire compression process is obtained, and the piston
The leakage of fluid from the high pressure chamber (35) to the low pressure chamber (34) via the outer peripheral surface of (9) and the inner peripheral surface of the cylinder chamber (6a) is suppressed, and the swing compressor (1) High efficiency can be achieved.

Further, this resultant force (FC) is generated when the internal pressure of the high pressure chamber (35) becomes slightly higher than that of the low pressure chamber (34), and when the compression of the fluid is started, the piston (9) is always generated. Cylinder
Since the pressing force acts on the (6) side, even if there is a processing error on the outer peripheral surface of the piston (9) and the inner peripheral surface of the cylinder chamber (6a), it is possible to seal between both surfaces and both ( 9), (6
The manufacturing process of a) does not require high processing accuracy and simplifies the manufacturing process.

Moreover, since the piston (9) is rotatable around the shaft center (O2) of the eccentric pin (42), the cylinder chamber
If a liquid fluid flows into (6a) and a liquid is compressed, or if foreign matter is mixed in, the eccentric pin (42) shaft center (O
2 ') moves so that it is located on the axis (O1) side of the drive shaft (5) with respect to the orthogonal line (K2) (above the orthogonal line (k2) in FIG. 5), and as shown in FIG. , The straight line in the direction in which the rotational force (FT) acts, that is, the axis of the eccentric pin (42) (O2 ') and the axis of the piston (9)
A straight line (k3 ') connecting (O3) and a line in the direction in which a hydraulic pressure (FG') greater than the fluid pressure (FG) acts, that is, the piston (9)
Let β be the angle formed by the straight line (K4) passing through the shaft center (O1) of the eccentric pin (4) by using this hydraulic pressure (FG ') and rotational force (FT).
The resultant force (FC ') of FG'tan β acts on the eccentric bush (11) around the shaft center (O2) of 2), and this resultant force (FC') causes the outer peripheral surface of the piston (9) to move to the cylinder chamber. It is possible to avoid liquid fluid and foreign matter by separating from the inner peripheral surface of (6a),
It is possible to prevent breakage of the blade (31) and breakage of the discharge valve (23).

[0023]

As described above, according to the swing compressor in the first aspect of the invention, the resultant force of the fluid pressure acting on the piston and the rotational force acting on the eccentric bush from the drive shaft causes the piston and the cylinder to move. Since it acts toward the eccentric direction, the outer peripheral surface of the piston can be pressed against the inner peripheral surface of the cylinder chamber in the entire compression process, and high precision is not required for processing the piston and cylinder. It is possible to suppress the generation of a gap between the two, prevent the fluid from leaking from the high pressure chamber to the low pressure chamber, and improve the efficiency of the swing compressor.

According to the swing compressor of the second aspect of the present invention, when the liquid is compressed in the cylinder chamber or foreign matter is mixed, the piston is separated from the inner peripheral surface of the cylinder and the liquid fluid and the foreign matter. By avoiding this, the rotary motion in the cylinder chamber can be maintained, and thus the reliability of the swing compressor can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional plan view near a compression element of a swing compressor according to an embodiment of the present invention.

FIG. 2 is a vertical side view of a swing compressor.

FIG. 3 is an exploded perspective view showing a configuration of a power transmission system of the swing compressor.

FIG. 4 is a diagram for explaining a force generated when a refrigerant gas is compressed as the drive shaft rotates.

FIG. 5 is a diagram corresponding to FIG. 1 for explaining a force at the time of liquid compression generated with the rotation of a drive shaft.

[Explanation of symbols]

 (1) Swing compressor (5) Drive shaft (6) Cylinder (6a) Cylinder chamber (9) Piston (9a) Shaft hole (11) Eccentric bush (21) Suction port (22) Discharge port (24) Bush hole ( Hole) (31) Blade (32) Oscillating bush (34) Low pressure chamber (35) High pressure chamber (42) Eccentric pin (O1) Drive shaft axis (O2), (O2 ') Eccentric pin axis (O3 ) Piston shaft center (k1) Shaft center line (k2) Orthogonal line

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsumi Kato 1304 Kanaoka-machi, Sakai City, Osaka Daikin Industry Co., Ltd.Kanaoka Plant, Sakai Factory (72) Katsumi Kawahara 1304, Kanaoka-machi, Sakai City, Osaka Daikin Industry Co., Ltd. Sakai Works Kanaoka Plant (72) Inventor Takeyoshi Okawa 1304 Kanaoka-machi, Sakai City, Osaka Daikin Industries, Ltd.Kanaoka Plant Sakai Works (72) Takashi Hirouchi 1304, Kanaoka-cho, Sakai City, Osaka Daikin Industries Co., Ltd. Sakai Plant, Kanaoka Plant (72) Inventor, founder, 1304, Kanaoka Town, Sakai City, Osaka Prefecture Daikin Industries, Ltd., Kanaoka Plant, Sakai Plant

Claims (2)

[Claims] 1. A cylinder (6) having a cylinder chamber (6a) in which a suction port (21) and a discharge port (22) are opened, a drive shaft (5) introduced into the cylinder chamber (6a), An annular piston (9) which is arranged in the cylinder chamber (6a) and is rotatably fitted with the shaft center (O3) eccentric to the shaft center (O1) of the drive shaft (5); , A low pressure chamber (34) and a discharge port (2) which are connected to the outer periphery of the piston (9) in a protruding manner and communicate the cylinder chamber (6a) with the suction port (21).
A blade (31) which is divided into a high pressure chamber (35) communicating with 2) and a hole (24) formed in the cylinder (6) facing the cylinder chamber (6a) so as to be swingable, Blade above (31)
Of the drive shaft (5) is provided with a swinging bush (32) that swingably and reciprocally supports the protruding tip side of the drive shaft (5).
In the swing compressor (1) configured to revolve in the cylinder chamber (6a) with the rotation of the, the eccentric bush (11) is rotatable in the shaft hole (9a) of the piston (9). While the eccentric bush (11) and the drive shaft (5) are fitted to the shaft center of the drive shaft (5),
(O1) is rotatably connected by an eccentric pin (42) which is eccentric to the drive shaft (5) and the piston (9). Piston with respect to the axis (k1) passing through
The axis of the drive shaft (5) with respect to the orthogonal line (k2) located on the rotation direction side of (9) and passing through the axis (O3) of the piston (9) at right angles to the axis (k1). A swing compressor having a shaft center (O2) located on the opposite side of the (O1) position. 2. The piston (9) has a shaft center (O) of the eccentric pin (42) so that the eccentric amount with respect to the cylinder (6) is variable.
2. The swing compressor according to claim 1, which is rotatably supported around 2).