JP3084145B2 - Reciprocating compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating compressor suitably used, for example, as an air compressor, and more particularly to a reciprocating compressor having an unload mechanism for controlling a load operation and an unload operation.

[0002]

2. Description of the Related Art FIGS. 13 to 17 show a conventional reciprocating compressor.

In the drawing, reference numeral 1 denotes a cylinder formed in a substantially cylindrical shape, and a plurality of radiation fins 1 are provided on the outer peripheral side of the cylinder 1.
A, 1A,... Are provided. The upper end 1B of the cylinder 1 has a substantially square outer shape corresponding to a later-described valve seat plate 4 shown in FIGS. 14 and 15, and a cylinder head 9 and a valve seat plate 4 described later (Only one is shown).

Reference numeral 3 designates a step as a stopper formed on the inner periphery of the end face of the upper end 1B of the cylinder 1, and the step 3 is a valve opening of a valve plate 15 of a suction valve 13 described later. Is regulated.

Reference numeral 4 denotes a valve seat plate provided on the upper end 1B of the cylinder 1. The valve seat plate 4 is formed as a substantially square flat plate as shown in FIGS. A compression chamber 5 is defined in the cylinder 1 between them. The valve seat plate 4 is provided with three elliptical suction holes 6, 6, 6 and 4 located inside the piston 12 along the outer circumference of the circular orbit of the piston 12 so as to communicate with the compression chamber 5. Each of the discharge holes 7, 7,... Is formed. Also, four bolt insertion holes 8, 8,... Are formed at the corners of the valve seat plate 4, and a cylinder head 9 is inserted into each of the bolt insertion holes 8 through the valve seat plate 4. Then, a bolt 2 screwed to the end face of the upper end 1B of the cylinder 1 is inserted.

Reference numeral 9 denotes a cylinder head mounted on the cylinder 1 via a valve seat plate 4. The cylinder head 9 has a suction chamber 10 and a discharge chamber 11 between the valve seat plate 4 and the cylinder head 9. 9A is formed. Further, a suction port 9B and a discharge port 9C are formed in the cylinder head 9, the suction port 9B communicates with each suction hole 6 through a suction chamber 10, and the discharge port 9C is connected to the discharge chamber 11
And is communicated with each of the discharge holes 7. Further, on the suction chamber 10 side, a mounting hole 9D is formed in which an unloading mechanism 19 described later is mounted.

Reference numeral 12 denotes a piston slidably inserted into the cylinder 1 and having a piston ring 12A and a rider ring 12B mounted thereon. The piston 12 is connected to a connecting rod 12C.
The piston 12 is reciprocated in the cylinder 1 by rotating the crankshaft with a drive source such as an electric motor. The piston 12 opens the suction valve 13 to suck the air in the suction chamber 10 into the compression chamber 5 during the suction stroke in which the piston 12 reciprocates in the cylinder 1, and the suction valve 1 during the discharge stroke.
3 is closed, and a discharge valve 16 described later is opened to discharge compressed air from the compression chamber 5 into the discharge chamber 11.

Reference numeral 13 denotes a valve seat plate 4 for opening and closing each suction hole 6.
The suction valve 13 is fixed to the lower surface of the valve seat plate 4 at both ends by short bolts 14, 14 to form a reed valve body formed in a horseshoe shape by a thin plate. The suction chamber 10 communicates with the compression chamber 5 through each suction hole 6 and is shut off by being separated from and seated on the lower surface of the valve seat plate 4 when the piston 12 reciprocates. When the valve plate 15 of the suction valve 13 is opened, the distal end side is in contact with the step 3 of the cylinder 1, and the lift amount as the valve opening is regulated.

Reference numerals 16, 16,... Denote discharge valves which are located in the discharge chamber 11 and are mounted on the upper surface side of the valve seat plate 4 so as to open and close the discharge holes 7, respectively. Bolts 17, 17, 17.
And a long valve plate 18 fixed by.

Reference numeral 19 denotes an unloading mechanism located above the central suction hole 6 and mounted in the mounting hole 9D of the cylinder head 9. The unloading mechanism 19 covers the upper opening of the mounting hole 9D. It is roughly constituted by a connection portion 19A which is screwed so as to be supplied with a signal air, and a push rod 20 which is slidably inserted into the mounting hole 9D and formed in a stepped cylindrical shape.

The push rod 20 has a large-diameter rod portion 20A serving as an unloading piston defining an air chamber 21 between the push rod 20 and the connection portion 19A.
0A, a small-diameter rod portion 20B formed on the distal end side of the suction valve 13A.
Is a contact surface that pushes the valve plate 15.

An O-ring 22 for sealing the space between the mounting hole 9D and the push rod 20 in a liquid-tight manner is provided on the outer periphery of the large-diameter rod portion 20A of the push rod 20 on the base end side.
Annular concave portions 20D and 20E are formed in which urging springs 23 for urging the push rod 20 upward are respectively mounted.

In the unloading mechanism 19, when the signal air is supplied to the air chamber 21 via the connecting portion 19A, the pressure is pushed against the urging spring 23 by the pressure as shown in FIG. The rod 20 is pushed downward,
When the compressor is started, the valve plate 15 of the suction valve 13 is moved to the stepped portion 3 by the distal end portion 20C of the small diameter rod portion 20B of the push rod 20.
To maintain the suction valve 13 in the open state.
As a result, the compressor is unloaded.

Reference numerals 24 and 25 denote gaskets which are mounted on the upper and lower surfaces of the valve seat plate 4 and serve as sealing members for sealing between the cylinder head 9 and the cylinder 1 in a liquid-tight manner. Further, reference numeral 26 denotes a fixing bolt for fixing the valve seat plate 4 and the cylinder head 9.

In the prior art constructed as described above, during a load operation, when the crankshaft is driven to rotate by a drive source (not shown) such as an electric motor and the piston 12 is reciprocated in the cylinder 1, for example, air External air is sucked from the suction port 9B via a filter (not shown) or the like, and this air is sucked from the suction chamber 10 into the compression chamber 5 via the suction hole 6 when the suction valve 13 is opened. . The air in the compression chamber 5 is compressed by the piston 12 and
6 is opened by pushing up the valve plate 18 upward,
Compressed air is discharged from each discharge hole 7 into the discharge chamber 11.

In this case, in the suction stroke in which the piston 12 reciprocates in the cylinder 1, each discharge valve 16 is closed and the suction valve 13 is opened. In the discharge stroke, the suction valve 13 is closed and each discharge valve is closed. Since the valve 16 is opened, the compressed air is sequentially discharged into the discharge chamber 11 in accordance with the opening and closing of each of the discharge valves 16, and the compressed air is connected to the discharge port 9C via an air conduit or the like. (Not shown).

[0017]

In the above-mentioned prior art, three suction holes 6 are formed in one horseshoe-shaped valve plate 15.
The suction valve 13 which opens and closes with the piston 1
Opening and closing are repeated by the movement of 2.

That is, in the suction stroke in which the piston 12 moves downward, the valve plate 15 contacts the step 3, and the valve plate 18 of each discharge valve 16 closes. On the other hand, during the discharge stroke in which the piston 12 moves upward, the valve plate 15 of the suction valve 13
Is pressed against the valve seat plate 4 by the pressure increase in the compression chamber 5 and is closed, and the valve plate 18 of each discharge valve 16 is opened.

At the time of unloading operation when the unloading mechanism 19 is operated, as shown in FIG. 17, the distal end portion 20C of the small diameter rod portion 20B of the push rod 20 causes the valve plate of the suction hole 6 located at the center to be opened. 15 is pressed in a manner close to point contact, and the valve plate 15 is brought into contact with the step portion 3 to open the valve.

As described above, since the pressing against the valve plate 15 is performed by the point contact of the distal end portion 20C of the push rod 20, especially when the unloading mechanism 19 is operated,
There is a problem that the force from the push rod 20 is concentrated on one point of the valve plate 15 and the valve plate 15 is damaged.

Further, the push rod 20 of the unloading mechanism 19 is slidably inserted into the mounting hole 9D of the cylinder head 9;
In the case of C, the position shift is apt to occur, and when the push rod 20 shifts, there is a problem that the breakage of the valve plate 15 is further promoted.

The present invention has been made in view of the above-described problems of the prior art, and the present invention can prevent damage to a valve plate by expanding a contact surface between a valve plate of a suction valve and a push rod of an unloading mechanism. It is intended to provide a reciprocating compressor.

[0023]

The first aspect of the present invention for solving the above-mentioned problems is characterized in that the push rod of the unloading mechanism includes a large-diameter rod, and a tip of the large-diameter rod. An annular step formed between the small-diameter rod part and the large-diameter rod part, which is positioned between the small-diameter rod part and the large-diameter rod part, and which pushes the valve body toward the stopper part by contacting the valve body surface of the suction valve A valve body of the suction valve is formed by a thin valve plate having both ends fixed to a valve seat plate, and a small-diameter rod portion of the push rod is inserted into an intermediate portion of the valve plate. And a guide hole for guiding the small-diameter rod portion of the push rod is formed in the stopper portion.

Further, the second invention adopts a configuration in which the push rod of the unloading mechanism includes a large-diameter rod, a small-diameter rod located at the tip end of the large-diameter rod, and a small-diameter rod. Formed between the part and the large-diameter rod part,
An annular step portion that pushes the valve body toward the stopper portion by contacting the valve body surface of the suction valve, and the valve bodies of the suction valve face each other with a free end on the tip side, A base end side is formed by a pair of thin valve plates fixed to a valve seat plate at a position away from the suction valve, and a small-diameter rod portion of the push rod is inserted into a free end of each valve plate. A guide hole for guiding the small-diameter rod portion of the push rod is formed in the stopper portion.

Further, the suction valve may be provided with a retainer for regulating a lift amount of the valve plate, and the retainer may be formed with a guide hole for guiding a small diameter rod portion of the push rod.

[0026]

According to the above construction, in the first invention, the valve body of the suction valve is constituted by one valve plate, and is formed by an annular step formed between the large-diameter rod and the small-diameter rod of the push rod. By pushing the valve plate, the contact area between the push rod and the valve plate can be increased, and the displacement of the push rod can be prevented by guiding the small-diameter rod portion to the guide hole of the stopper portion.

In the second invention, the valve body of the suction valve is constituted by a pair of valve plates, and each of the valves is formed by an annular step formed between the large-diameter rod and the small-diameter rod of the push rod. By pushing the distal end side of the plate, the contact area between the push rod and the valve plate can be increased, and the displacement of the push rod can be prevented by guiding the small-diameter rod portion to the guide hole of the stopper portion. .

Further, a retainer for regulating the valve opening of the valve body is provided in the suction valve, a guide hole is formed in the retainer, and a small-diameter rod portion of the push rod is guided in the guide hole, so that the position of the push rod is reduced. Prevent displacement.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In the embodiment, the same components as those in the prior art shown in FIGS. 13 to 17 are denoted by the same reference numerals, and description thereof will be omitted.

FIGS. 1 to 4 show a first embodiment of the present invention.

In the figure, reference numeral 31 denotes a guide hole located in the step portion 3 of the cylinder 1 and formed in the axial direction.
1 is a small diameter rod portion 33B of a push rod 33 described later.
Is to be guided.

Reference numeral 32 denotes an unloading mechanism according to the present embodiment. The unloading mechanism 32 is substantially the same as the unloading mechanism 19 of the prior art, and has a central suction hole among the suction holes 6 formed in the valve seat plate 4. 6 and a mounting hole 9 formed above
D, which covers the upper opening of the mounting hole 9D, is slidably inserted into the mounting hole 9D, and is formed into a stepped cylindrical shape. And a push rod 33.

The push rod 33 has a large-diameter rod portion 33A serving as an unload piston defining an air chamber 34 between the push rod 33 and the connection portion 32A.
A small-diameter rod portion 33B located on the distal end side of A, and formed between the small-diameter rod portion 33B and the large-diameter rod portion 33A,
An annular step 33C is provided as a contact surface for pushing the valve plate 39 of the suction valve 37 described later.

An O-ring 35 for sealing the space between the mounting hole 9D and the push rod 33 in a liquid-tight manner is provided on the outer periphery of the large-diameter rod portion 33A of the push rod 33 on the base end side.
Annular concave portions 33D and 33E are formed in which an urging spring 36 for urging the push rod 33 upward is mounted.

Further, the push rod 3 according to the present embodiment
3 is formed such that the axial dimension of the large-diameter rod portion 33A is longer than that of the conventional push rod 20. When the unloading mechanism 32 is not operated as shown in FIG. When the unloading mechanism 32 is actuated as shown in FIG. 4, the length is such that the annular plate 33C pushes the valve plate 39 downward. Is set to On the other hand, the distal end side of the small-diameter rod portion 33B is always inserted into the guide hole 31 via the insertion hole 40 of the valve plate 39.

Reference numeral 37 denotes a valve seat plate 4 for opening and closing each suction hole 6.
The suction valve 37 of this embodiment is provided on the lower surface of the valve seat 4. The suction valve 37 has both ends fixed to the lower surface of the valve seat plate 4 by short bolts 38, 38, and is formed in a horseshoe shape by a thin plate. The valve plate 39 according to the present embodiment is constituted by a valve plate 39 serving as a reed valve body, but an insertion hole 40 into which the small diameter rod portion 33B of the push rod 33 is inserted is formed in an intermediate portion of the valve plate 39 according to the present embodiment. Have been.

In the suction stroke in which the piston 12 reciprocates in the cylinder 1, the suction valve 37 is used for the valve plate 3.
The valve 9 is separated from the valve seat plate 4 and comes into contact with the step portion 3 to open the valve. In the discharge stroke, the valve plate 39 is seated on the valve seat plate 4 to close the valve.

That is, at the time of the normal compression operation (at the time of the load operation) in which the unload mechanism 32 is not operated, the small diameter rod portion 33B of the push rod 33 is inserted into the insertion hole 40 of the valve plate 39 as shown in FIG. The valve plate 39 is inserted, the valve plate 39 moves between the valve seat plate 4 and the step portion 3 with the reciprocating motion of the piston 12 with the small-diameter rod portion 33B still inserted, and opens and closes the valve. Repeat.

On the other hand, during the unload operation in which the unload mechanism 32 is operated, as shown in FIG.
The signal air is supplied to the air chamber 34 via the, and the push rod 33 moves downward. Then, the upper side near the insertion hole 40 of the valve plate 39 is formed with the annular step portion 33C of the push rod 33.
Is pushed downward, thereby disengaging the valve plate 39 from the valve seat plate 4, bringing the valve plate 39 into contact with the stepped portion 3, and connecting the suction chamber 10 and the compression chamber 5 through the respective suction holes 6. Communication.

The reciprocating compressor according to the present embodiment has the above-described configuration, and its basic operation is not particularly different from that of the prior art.

In this embodiment, however, the unloading mechanism 3
In the unload operation for operating the valve 2, the valve plate 39 is pushed by the annular step 33 C formed on the push rod 33, so that the contact area for pushing the valve plate 39 is the area of the annular step 33 C. As a result, a large force can be secured, and the force from the push rod 33 can be prevented from being concentrated on one point of the valve plate 39 and dispersed. Then, the breakage of the valve plate 39 can be reliably prevented.

Further, since the small-diameter rod portion 33B of the push rod 33 of the unloading mechanism 32 is guided by the guide hole 31 formed in the step portion 3 serving as the stopper portion, the displacement of the push rod 33 is surely ensured. And the breakage of the valve plate 39 can be effectively prevented.

Accordingly, damage to the valve plate 39 of the suction valve 37 can be reliably prevented, and as a result, the life of the reciprocating compressor can be significantly extended.

FIGS. 5 to 7 show a second embodiment of the present invention. The feature of this embodiment is that the valve element of the suction valve is constituted by a pair of thin valve plates. . The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the drawing, reference numeral 41 denotes a valve seat plate according to the present embodiment. The valve seat plate 41 is provided on the upper end portion 1B of the cylinder 1 and has a substantially square shape like the valve seat plate 4 of the prior art. It is formed as a flat plate. The valve seat plate 41 has two oblong suction holes 42, 42 formed along the outer circumference of the circular orbit of the piston 12 so as to allow the compression chamber 5 and the suction chamber 10 to communicate with each other. A rod insertion hole 43 formed between the suction holes 42, through which the large-diameter rod portion 33A of the push rod 33 is inserted, and the compression chamber 5 and the discharge chamber 11 are formed so as to communicate with each other. Are formed from the plurality of discharge holes 44. Further, four bolt insertion holes 45, 45,... Are formed at the corners of the valve seat plate 41, and the cylinder head 9 is inserted into each of the bolt insertion holes 45 via the valve seat plate 41. Bolt 2 screwed to the end face of the upper end 1B of the cylinder 1
Is inserted.

Reference numeral 46 denotes a suction valve according to this embodiment. The suction valve 46 is used to open and close the suction holes 42 on the valve seat plate 41.
The suction valve 46 is fixed to the lower surface of the valve seat plate 41 at its base end by short bolts 47, 47, and the front end side is a free end. A pair of valve plates 48 and 4 serving as reed valve bodies formed in
And a concave portion 48 into which the small-diameter rod portion 33B of the push rod 33 is inserted.
A and 48A are respectively formed.

Then, the suction valve 46 constructed as described above is used.
During the unloading operation in which the unloading mechanism 32 operates, each of the valve plates 48 is pushed by the annular step portion 33C of the push rod 33 as shown in FIG. With this, the suction valve 46 is opened. Further, by inserting the concave portion 48A of each valve plate 48 into the small diameter rod portion 33B of the push rod 33,
The position of each valve plate 48 is shifted.

Thus, also in the present embodiment constructed as described above, since each valve plate 48 of the suction valve 46 can be pushed by the annular step portion 33C of the push rod 33, almost the same as in the first embodiment. Similar functions and effects can be obtained.

FIGS. 8 to 12 show a third embodiment of the present invention. The feature of this embodiment is that a suction valve is provided with a retainer for restricting the rotation of a valve body. A guide hole for guiding the small diameter rod portion of the push rod is formed. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the drawing, reference numeral 51 denotes a valve seat plate according to the present embodiment. The valve seat plate 51 is provided on the upper end portion 1B of the cylinder 1 and has a substantially square shape like the conventional valve seat plate 4. It is formed as a flat plate. The valve seat plate 51 is provided with two oblong suction holes 52, 52 formed along the inner circumference of the circular orbit of the piston 12 so as to allow the compression chamber 5 and the suction chamber 63 to communicate with each other. The compression chamber 5 and the discharge chamber 64 communicate with the rod insertion hole 53 formed between the suction holes 52 and through which the large-diameter rod portion 66A of the push rod 66 is inserted. The four discharge holes 54, 54, ...
Consists of Further, four bolt insertion holes 55, 55,... Are formed at the corners of the valve seat plate 51, and a cylinder head 62, which will be described later, is inserted into each of the bolt insertion holes 55. A bolt 2 screwed into the end surface of the upper end portion 1B of the cylinder 1 is inserted through the.

Reference numeral 56 denotes a suction valve according to the present embodiment. The suction valve 56 is used to open and close each suction hole 52.
The suction valve 56 is fixed to the lower surface of the valve seat plate 51 at both ends by short bolts 57, 57, and becomes a reed valve body formed in a horseshoe shape by a thin plate. 58 and a retainer 59 for regulating the valve opening of the valve plate 58.

Here, an insertion hole 60 into which the small-diameter rod portion 66B of the push rod 66 is inserted is formed in an intermediate portion of the valve plate 58. In the middle of the retainer 59, a stopper 59A positioned at the step 3 is formed so as to protrude, and a guide hole 61 through which the small-diameter rod 66B of the push rod 66 is guided is formed. .

Reference numeral 62 denotes a cylinder head according to this embodiment. The cylinder head 62 has a suction chamber 63 and a discharge chamber between the valve seat plate 51 and the cylinder head 62 in substantially the same manner as the conventional cylinder head 9. 64, a partition 62A, a suction port 62B, and a discharge port 62C are formed, and a mounting hole 62D in which an unloading mechanism 65 described later is provided is provided on the suction chamber 63 side.
It is formed so as to be located on one rod insertion hole 53.

Reference numeral 65 denotes an unloading mechanism. The unloading mechanism 65 includes a connecting portion 65A provided to cover the opening of the mounting hole 62D, similarly to the unloading mechanism 32 of the first embodiment. And a push rod 66 slidably inserted in the mounting hole 62D.

Here, the push rod 66 has a large-diameter rod portion 66A serving as an unload piston that defines an air chamber 67 between the push rod 66 and the mounting hole 62D.
A small-diameter rod portion 66B located on the tip side of A, and formed between the small-diameter rod portion 66B and the large-diameter rod portion 66A,
An annular stepped portion 66C is provided as a contact surface for pushing the valve plate 58 of the suction valve 56.

The O-ring 68 and the push rod 66 for sealing the space between the mounting hole 62D and the push rod 66 are urged upward on the outer periphery of the large-diameter rod portion 66A of the push rod 66 on the proximal end side. Annular concave portions 66D and 66E in which the urging spring 69 is mounted are formed.

A gasket 70 seals the valve seat plate 51 and the upper end 1B of the cylinder 1.

During the unloading operation for operating the unloading mechanism 65 configured as described above, the valve plate 58 of the suction valve 56 is pushed downward by the annular step 66C of the push rod 66 as shown in FIG. The suction valve 56 is opened by bringing the valve plate 58 into contact with the retainer 59.

Thus, also in this embodiment constructed as described above, since the valve plate 58 of the suction valve 56 is pushed by the annular step 66C of the push rod 66, the contact area of the valve plate 58 can be increased. Since the small-diameter rod portion 66B is guided by the guide hole 61 formed in the retainer 59, the displacement of the push rod 66 can be prevented, and substantially the same effect as in the first embodiment can be obtained. .

Incidentally, also in the third embodiment, the valve plate 58 of the suction valve 56 is constituted by a pair of valve plates as in the second embodiment. In this case, the free ends of each valve plate are provided. May be pushed by the annular step 66C of the push rod 66.

In each of the above embodiments, the suction valve 3
Although the shape of the valve plates 39, 48, 58 of 7, 46, 56 is formed in a horseshoe shape, the present invention is not limited to this, and the valve plates 39, 48, 58 may be formed in a "-" shape. The retainer 59 according to this embodiment may also be formed in a “<” shape.

[0062]

As described in detail above, according to the first aspect,
A push rod of an unloading mechanism for pushing a valve element of a suction valve is connected to a large-diameter rod, a small-diameter rod formed on the distal end side of the large-diameter rod, and a small-diameter rod and a large-diameter rod. An annular step portion for pushing the valve body surface of the suction valve, wherein the valve body of the suction valve is formed of a thin plate-like valve plate,
An insertion hole into which the small-diameter rod portion of the push rod is inserted is formed in an intermediate portion of the valve plate, and a guide hole through which the small-diameter rod portion is guided is formed in a stopper portion that regulates the valve opening of the suction valve. Therefore, the valve plate can be pushed with a large contact area by the annular step portion of the push rod, and the concentration of the force on one point of the valve plate can be dispersed. Further, the displacement of the push rod can be prevented by the guide hole of the stopper portion. Therefore, damage to the valve plate of the suction valve can be reliably prevented, and the life of the reciprocating compressor can be significantly extended.

On the other hand, according to the second invention, the push rod of the unload mechanism for pushing the valve element of the suction valve is provided with a large-diameter rod, a small-diameter rod formed on the distal end side of the large-diameter rod, and An annular step portion for pushing the valve body surface of the suction valve between the small-diameter rod portion and the large-diameter rod portion, and each base end of the valve body of the suction valve is fixed to a valve seat plate; The end is formed by a pair of thin valve plates pushed by the annular step portion of the push rod, and a guide hole for guiding the small-diameter rod portion is formed in a stopper portion where the opening degree of the suction valve is regulated. Therefore, the free end of each valve plate can be pushed with a large contact area by the annular step portion of the push rod, and the force for pushing each valve plate can be dispersed at one point. Further, the displacement of the push rod can be prevented by the guide hole of the stopper portion. Therefore, damage to the valve plate of the suction valve can be reliably prevented, and the life of the reciprocating compressor can be significantly extended.

Further, even when the valve opening of the valve body of the suction valve is regulated by a retainer, the displacement of the push rod can be prevented by forming a guide hole for guiding the small-diameter rod portion in the retainer. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a reciprocating compressor according to a first embodiment of the present invention.

FIG. 2 is a plan view of a valve seat plate and a suction valve in FIG. 1 as viewed from a compression chamber.

3 is a cross-sectional view showing a load operation state in which an unloading mechanism is not operated, as viewed from a direction indicated by arrows III-III in FIG. 1;

FIG. 4 is a sectional view similar to FIG. 3, showing an unload operation state in which the unload mechanism according to the first embodiment is operated.

FIG. 5 is a plan view of a valve seat plate and a suction valve according to a second embodiment of the present invention as viewed from a compression chamber side.

FIG. 6 is a cross-sectional view showing a load operation state in which the unloading mechanism similar to FIG. 3 according to the second embodiment is not operated.

FIG. 7 is a cross-sectional view similar to FIG. 6, showing an unload operation state in which an unload mechanism according to a second embodiment is operated.

FIG. 8 is a longitudinal sectional view showing a reciprocating compressor according to a third embodiment of the present invention.

9 is a cross-sectional view as seen from the direction of arrows IX-IX in FIG.

FIG. 10 is a plan view of a valve seat plate and a suction valve according to a third embodiment as viewed from a compression chamber side.

FIG. 11 is a cross-sectional view showing a load operation state in which the unload mechanism is not operated, as viewed from the direction indicated by arrows XI-XI in FIG. 8;

FIG. 12 is a sectional view similar to FIG. 11, showing an unload operation state in which the unload mechanism according to the third embodiment is operated.

FIG. 13 is a longitudinal sectional view showing a conventional reciprocating compressor.

FIG. 14 is a cross-sectional view as seen from the direction indicated by arrows XIV-XIV in FIG.

FIG. 15 is a plan view of a valve seat plate and a suction valve according to the related art as viewed from the compression chamber side.

FIG. 16 is a cross-sectional view showing a load operation state in which the unloading mechanism is not operated, as viewed from a direction indicated by arrows XVI-XVI in FIG.

FIG. 17 is a cross-sectional view similar to FIG. 16, showing an unload operation state in which the unload mechanism according to the related art is operated.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 3 Step part (stopper part) 4,41,51 Valve seat plate 5 Compression chamber 6,42,52 Suction hole 7,44,54 Discharge hole 9,62 Cylinder head 10,63 Suction chamber 11,64 Discharge chamber 12 Piston 13, 37, 46, 56 Suction valve 15, 39, 48, 58 Valve plate (valve element) 16 Discharge valve 32, 65 Unload mechanism 33, 66 Push rod 33A, 66A Large diameter rod part 33B, 66B Small diameter rod part 33C, 66C Annular step 40, 60 Insertion hole 31, 61 Guide hole 59 Retainer

Claims (3)

(57) [Claims] 1. A cylinder, a valve seat plate provided on an end of the cylinder and having a suction hole and a discharge hole communicating with the cylinder, and mounted on the cylinder via the valve seat plate. A cylinder head defining a suction chamber communicating with the suction hole and a discharge chamber communicating with the discharge hole between the valve seat plate and the valve seat plate. A piston that defines a compression chamber and a valve body that opens and closes a suction hole of the valve seat plate when the piston reciprocates are attached to the valve seat plate, and the suction chamber and the compression chamber are connected to each other by a suction hole. A suction valve communicating with the suction valve, a stopper provided at an end of the cylinder located on the compression chamber side for regulating a valve opening of the suction valve, and the valve seat when the piston reciprocates. Attached to the valve seat plate to open and close the discharge hole of the plate, discharges the compression chamber and discharge chamber An unloading mechanism comprising: a discharge valve that communicates through a hole; and a push rod that is provided on the cylinder head and that pushes a valve body of the suction valve toward the stopper to forcibly open the suction valve. In the reciprocating compressor, the push rod of the unloading mechanism includes a large-diameter rod, a small-diameter rod located on the distal end side of the large-diameter rod, and the small-diameter rod and the large-diameter rod. And an annular step portion that is pressed between the stopper body and the stopper by contacting the valve body surface of the suction valve. It is formed by a thin valve plate fixed to a valve seat plate, and an insertion hole into which a small-diameter rod portion of the push rod is inserted is formed in an intermediate portion of the valve plate, and a push hole is formed in the stopper portion. The small diameter rod part of the rod is guided Reciprocating compressor, characterized in that the formation of the guide hole. 2. A cylinder, a valve seat plate provided on an end of the cylinder and having a suction hole and a discharge hole communicating with the cylinder, and mounted on the cylinder via the valve seat plate. A cylinder head defining a suction chamber communicating with the suction hole and a discharge chamber communicating with the discharge hole between the valve seat plate and the valve seat plate. A piston that defines a compression chamber and a valve body that opens and closes a suction hole of the valve seat plate when the piston reciprocates are attached to the valve seat plate, and the suction chamber and the compression chamber are connected to each other by a suction hole. A suction valve communicating with the suction valve, a stopper provided at an end of the cylinder located on the compression chamber side for regulating a valve opening of the suction valve, and the valve seat when the piston reciprocates. Attached to the valve seat plate to open and close the discharge hole of the plate, discharges the compression chamber and discharge chamber An unloading mechanism comprising: a discharge valve that communicates through a hole; and a push rod that is provided on the cylinder head and that pushes a valve body of the suction valve toward the stopper to forcibly open the suction valve. In the reciprocating compressor, the push rod of the unloading mechanism includes a large-diameter rod, a small-diameter rod located on the distal end side of the large-diameter rod, and the small-diameter rod and the large-diameter rod. And an annular step portion which is pressed between the valve body and the stopper by contacting the valve body surface of the suction valve, and the valve body of the suction valve has a free tip end side. The push rods are formed by a pair of thin valve plates fixed to the valve seat plate at positions where the base ends are opposed to each other and the base end is away from the suction valve, and the free ends of the respective valve plates are provided. Through the small diameter rod section of Reciprocating compressor, characterized in that the formation of the guide hole diameter rod portion of the push rod is guided in the stopper. 3. The suction valve according to claim 1, wherein a retainer for regulating a lift amount of the valve plate is provided, and a guide hole for guiding a small diameter rod portion of the push rod is formed in the retainer. The reciprocating compressor as described.