JP2008031957A - Reciprocating compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reciprocating compressor wherein a gap between a piston at the top-dead center and a valve-seat member is made narrow to improve compression efficiency. <P>SOLUTION: An intake-valve-holding recessed grooved 16 is provided in the valve-seat member 15 in the flat compression-chamber side-surface 15B facing to a retainer 8 of the piston 6. In the intake-valve-holding recessed groove 16, an intake valve 17 and an intake-valve receptor 18 are held. Thus, the compression chamber side-surface 15B of the valve seat member 15 is made almost flat by filling up the intake-valve-holding recessed-groove 16 with the intake valve 17 and the intake-valve receptor 18. The piston 6 can be brought close to the compression-chamber side-surface 15B to narrow the invalid gap G formed between the upper face 8A of the retainer 8 and the compression chamber side-surface 15B. The intake-valve-holding recessed-groove 16 can be narrowed by directly holding the intake valve 17 and the intake-valve receptor 18 in the intake-valve holding recessed-groove 16. Thus, the compression efficiency at the time when the piston is positioned at the top-dead center can be increased. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a reciprocating compressor suitably used to compress a fluid such as air.

  Generally, as a reciprocating compressor, a reciprocating type air compressor is known in which a piston is reciprocated in a cylinder so that air sucked in a suction stroke is compressed and discharged in a discharge stroke. (For example, refer to Patent Document 1).

Japanese Patent Laid-Open No. 10-68382

  A conventional reciprocating compressor of this type includes a cylinder attached to a crankcase, a piston connected to a crankshaft and reciprocating in the cylinder, a cylinder head mounted on the tip of the cylinder, and the cylinder A compression chamber is defined between the head and the cylinder and is defined by a valve seat member having a suction port and a discharge port that open to the compression chamber.

  The valve seat member is provided with a suction valve for opening and closing the suction port so as to overlap the side surface of the compression chamber facing the piston, and a discharge valve for opening and closing the discharge port so as to overlap the side surface of the cylinder head. Further, the valve seat member is provided with a valve receiver for regulating the angle when each valve is opened in order to prevent the compression performance from being lowered due to the delay in closing.

  In the reciprocating compressor, while the piston reciprocates in the cylinder, in the suction stroke from the top dead center to the bottom dead center, the suction valve is opened and the outside air is sucked into the compression chamber from the suction port. Further, in the discharge stroke from the bottom dead center to the top dead center, the suction valve is closed and the discharge valve is opened, whereby compressed air is supplied from the discharge port to an external air tank or the like.

  By the way, since the reciprocating compressor by the prior art mentioned above has attached the suction valve and the valve seat on the compression chamber side surface of the valve seat member, the suction valve and the valve seat protrude from the compression chamber side surface to the compression chamber side. Yes. In this case, the reciprocating compressor needs to increase the clearance (top clearance) between the piston located at the top dead center and the valve seat member so that the piston does not interfere with the valve receiver at the top dead center of the piston. . Alternatively, it is conceivable to provide a concave portion on the front end surface of the piston and to avoid interference with the suction valve and the valve receiver by this concave portion.

  However, the gap formed between the piston located at the top dead center and the valve seat member is an invalid gap that does not contribute to discharge. There is a problem that the amount of compressed air remaining in the room increases and the compression efficiency decreases. In addition, when a recess is provided on the tip surface of the piston, it is necessary to consider the accumulation of dimensional tolerances of many parts constituting the reciprocating compressor as a positional deviation during assembly. In this case, the compression efficiency is also reduced.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to reduce the ineffective gap formed between the piston and the valve seat member when positioned at the top dead center, and to compress the compression. An object of the present invention is to provide a reciprocating compressor capable of improving efficiency.

  A reciprocating compressor according to the present invention includes a cylinder in which a piston is removably inserted, a cylinder head mounted at a tip of the cylinder, and a piston provided between the cylinder head and the cylinder. A valve seat member having a suction port and a discharge port that define a compression chamber therebetween and open to the compression chamber, a suction valve provided in the valve seat member for opening and closing the suction port, and a valve seat member And a discharge valve that opens and closes the discharge port.

  In order to solve the above-described problem, the invention adopts the feature of the structure of claim 1 in that the valve seat member has a flat compression chamber side surface facing the piston, and the valve seat member has a flat surface. In the present invention, a suction valve housing groove is provided on the side surface of the compression chamber, and the suction valve is housed in the suction valve housing groove.

  According to a second aspect of the present invention, the suction valve receiving concave groove is configured to receive a suction valve receiver that regulates an opening degree of the suction valve so as to overlap the valve opening side of the suction valve.

  According to the first aspect of the present invention, since the suction valve housing groove is provided on the side surface of the compression chamber of the valve seat member formed as a flat surface, the suction valve disposed on the compression chamber side is disposed in the suction valve housing groove. Can be accommodated. Further, when the suction valve is housed in the suction valve housing groove, the suction valve housing groove can be filled with the suction valve, and the compression chamber side surface of the valve seat member can be made substantially flat including the suction valve. .

  As a result, the piston when positioned at the top dead center can be brought closer to the side of the compression chamber of the valve seat member by the amount of the suction valve housed in the suction valve housing recess. In addition, the suction valve housing groove that directly houses the suction valve does not need to take into account the dimensional tolerances of other parts, so it must be formed to the minimum size that allows fluid to flow while housing the suction valve. Can do.

  As a result, an ineffective gap that is formed between the piston and the valve seat member when positioned at the top dead center and does not contribute to the discharge of the compressed fluid can be reduced. The amount of remaining compressed fluid can be reduced, and the compression efficiency can be improved.

  According to the invention of claim 2, the suction valve receiver provided on the valve opening side of the suction valve can regulate the opening degree of the suction valve in the suction stroke, so that it is compressed without loss due to the closing delay. The performance can be improved. In addition, since the suction valve receiver can be accommodated in the suction valve accommodating concave groove so as to overlap the valve opening side of the suction valve, the amount of the compressed fluid remaining in the compression chamber is reduced in substantially the same manner as in the first aspect. And the compression efficiency can be improved.

  Hereinafter, a swing type air compressor will be described as an example of a reciprocating compressor according to an embodiment of the present invention, and will be described in detail with reference to FIGS.

  In FIG. 1, reference numeral 1 denotes an oscillating air compressor. The air compressor 1 includes a crankcase 2, a crankshaft 3, an electric motor 4, a cylinder 5, a piston 6, a cylinder head 12, and a valve seat member, which will be described later. 15, a suction valve housing concave groove 16, a suction valve 17, a discharge valve 19 and the like.

  Reference numeral 2 denotes a crankcase in which a crank chamber is defined. A crankshaft 3 is rotatably supported by the crankcase 2 so as to be positioned in the crank chamber. In addition, an electric motor 4 serving as a drive source for the air compressor 1 is attached to the crankcase 2. The crankshaft 3 is connected to the output shaft 4 </ b> A of the electric motor 4 and can be rotationally driven while being eccentric by the electric motor 4.

  Reference numeral 5 denotes a cylinder provided on the crankcase 2, and the cylinder 5 is formed in a cylindrical shape. Further, the cylinder 5 has a base end in the axial direction abutted on the upper part of the crankcase 2 and is bolted together with a cylinder head 12 and the like which will be described later.

  Reference numeral 6 denotes an oscillating piston inserted in the cylinder 5 so as to be reciprocally movable. As shown in FIGS. 2 and 3, the piston 6 is formed in a substantially disk shape, and a retainer 8 that holds the lip seal 7 is attached to the upper surface side of the piston 6. The lip seal 7 surrounds the outer peripheral side of the piston 6 and hermetically seals between the outer peripheral surface of the piston 6 and the inner peripheral surface of the cylinder 5. Further, the upper surface 8A of the retainer 8 is formed as a flat surface facing a compression chamber side surface 15B of a valve seat member 15 described later.

  On the other hand, on the lower surface side (crankshaft 3 side) of the piston 6, the tip end side of the rod 9 is integrally provided. Further, the base end side of the rod 9 is rotatably connected to the crankshaft 3 via a bearing 10. As a result, the piston 6 reciprocates while swinging in the cylinder 5 by the rotational drive of the crankshaft 3, and forms a compression chamber 11 with the valve seat member 15 described later.

  Reference numeral 12 denotes a cylinder head mounted on the front end side of the cylinder 5 via a valve seat member 15 or the like. As shown in FIG. 4, the cylinder head 12 is formed as a substantially rectangular hollow block, and a partition wall 12A is provided in the inside thereof. The partition wall 12 </ b> A defines a suction chamber 13 and a discharge chamber 14 between the cylinder head 12 and the valve seat member 15. Further, the cylinder head 12 is provided with a suction port 12B that communicates the suction chamber 13 with the outside, and a discharge port 12C that communicates the discharge chamber 14 with the outside.

  Further, the cylinder head 12 is provided with a discharge valve receiver 12D located in the discharge chamber 14, and the discharge valve receiver 12D regulates an angle (opening) when a discharge valve 19 described later is opened. Is. As a result, the discharge valve receiver 12D prevents the backflow of compressed air due to the delay in closing the discharge valve 19.

  On the other hand, for example, four bolt insertion holes 12E are provided at the corners of the cylinder head 12, and the cylinder head 12 is connected to the cylinder 5 and the valve seat by bolts (not shown) inserted into the respective bolt insertion holes 12E. It is attached to the crankcase 2 together with the member 15 and the like.

  A valve seat member 15 is provided between the cylinder 5 and the cylinder head 12. The valve seat member 15 is located in the cylinder 5 and defines the compression chamber 11 between the valve seat member 15 and the piston 6, and is formed as a substantially rectangular plate. The valve seat member 15 has a flat cylinder head side surface 15A on the upper side on the cylinder head 12 side and a compression chamber side surface 15B on the lower side on the compression chamber 11 (cylinder 5) side. The compression chamber side surface 15B faces the upper surface 8A of the retainer 8 of the piston 6 and is formed as a flat surface.

  The valve seat member 15 has a suction port 15C that opens to communicate with the suction chamber 13 and the compression chamber 11 on the cylinder head 12 side, and a discharge port 15D that opens to communicate with the discharge chamber 14 and the compression chamber 11. And are provided. Here, the suction port 15 </ b> C opens at one end portion in a suction valve housing groove 16 described later. Furthermore, four bolt insertion holes 15 </ b> E are provided at the corners of the valve seat member 15 so as to correspond to the respective bolt insertion holes 12 </ b> E of the cylinder head 12.

  Reference numeral 16 denotes a suction valve housing groove provided on the compression chamber side surface 15B of the valve seat member 15, and the suction valve housing groove 16 is disposed at a position corresponding to the suction port 15C. Further, the suction valve housing concave groove 16 accommodates a suction valve 17 and a suction valve receiver 18 which will be described later, so that the compression chamber side surface 15B of the valve seat member 15 is attached with the suction valve 17 and the suction valve receiver 18 attached. It is trying to be flat. Thus, when the compression chamber side surface 15B of the valve seat member 15 is formed flat, there is no possibility that the piston 6 interferes with the suction valve 17 and the suction valve receiver 18, so the piston 6 located at the top dead center is compressed. It can be brought close to the room side surface 15B, and an ineffective gap G described later can be reduced. As a result, the amount of compressed air remaining in the compression chamber 11 without being discharged during operation can be reduced.

  As shown in FIG. 4, the suction valve housing concave groove 16 is formed as an elongated oval concave groove corresponding to the suction valve 17 and the suction valve receiver 18. A suction port 15 </ b> C of the valve seat member 15 is opened at one end portion of the suction valve housing concave groove 16 in the length direction.

  Here, in order to secure a clearance enough to allow air to flow without resistance between the suction valve 17 and the suction valve receiver 18, the suction valve housing concave groove 16 is slightly smaller than the suction valve 17 and the suction valve receiver 18. It is greatly formed. More specifically, since the suction valve housing groove 16 directly accommodates the suction valve 17 and the suction valve receiver 18, the dimensional tolerance considered when forming the suction valve housing groove 16 is the suction valve 17. And only the dimensional tolerance of the suction valve receiver 18. Therefore, the suction valve accommodating groove 16 can be set to the minimum size necessary for circulating air.

  Reference numeral 17 denotes a suction valve provided in the valve seat member 15, and the suction valve 17 is accommodated in the suction valve accommodation concave groove 16 of the valve seat member 15. The suction valve 17 is made of a thin and long thin plate having elasticity, and its base end side is a fixed end and is attached to the valve seat member 15, and the distal end side is a free end and the suction port of the valve seat member 15. 15C is covered so that opening and closing is possible. As a result, the suction valve 17 opens in a suction stroke for sucking external air into the compression chamber 11, and closes in a discharge stroke for discharging the compressed air from the compression chamber 11.

  Reference numeral 18 denotes a suction valve receiver housed in the suction valve housing concave groove 16, and the suction valve receiver 18 is disposed so as to overlap the lower side of the suction valve 17 which is the valve opening side. The suction valve receiver 18 regulates the opening when the tip end side of the suction valve 17 is bent downward and opened.

  The suction valve receiver 18 is made of a long and thin oblong thick plate, and its proximal end is attached to the valve seat member 15 at the other end of the suction valve housing groove 16. On the other hand, the front end side of the suction valve receiver 18 is formed to be gradually thinner toward the front end so as to widen the distance from the suction valve 17. Therefore, the suction valve receiver 18 can restrict the opening degree of the suction valve 17 at a predetermined angle while allowing the suction valve 17 to open in the suction stroke while allowing the suction valve 17 to open. Thereby, the suction valve receiver 18 prevents compressed air from leaking due to a delay in closing the suction valve 17.

  Here, the attachment form of the suction valve 17 and the suction valve receiver 18 with respect to the valve seat member 15 (suction valve accommodation concave groove 16) will be described. A suction valve 17 is arranged at the bottom of the suction valve housing concave groove 16, and a suction valve receiver 18 is arranged so as to overlap the lower side of the suction valve 17. In this state, both are screwed together on the valve seat member 15 side. Stop. Thereby, the suction valve 17 and the suction valve receiver 18 can be accommodated in the suction valve accommodation concave groove 16.

  At this time, the depth dimension of the suction valve housing concave groove 16 is set to be substantially the same as the thickness dimension in which the suction valve 17 and the suction valve receiver 18 are overlapped. Accordingly, the compression chamber side surface 15B of the valve seat member 15 can be filled by housing the suction valve 17 and the suction valve receiver 18 in the suction valve housing concave groove 16, so that the lower surface of the suction valve receiver 18 is covered with the side surface of the compression chamber. The entire compression chamber side surface 15B can be made flat as substantially the same surface as 15B.

  Since the compression chamber side surface 15B of the valve seat member 15 is flat without obstructing projections, as shown in FIG. 3, the upper surface 8A of the retainer 8 and the compression chamber side surface when the piston 6 is disposed at the top dead center. The ineffective gap G (top clearance) formed with 15B can be set to a minimum. Thereby, the amount of compressed air remaining in the compression chamber 11 and not contributing to discharge can be reduced.

  A discharge valve 19 is provided in the cylinder head side surface 15 </ b> A of the valve seat member 15 in the discharge chamber 14. The discharge valve 19 is formed of an elongated thin plate having elasticity. Further, the discharge valve 19 is attached to the valve seat member 15 with the base end side as a fixed end, and the front end side covers the discharge port 15D so that it can be opened and closed. As a result, the discharge valve 19 is closed in the suction stroke and opened in the discharge stroke, contrary to the suction valve 17. Further, the discharge valve 19 is in contact with the discharge valve receiver 12D of the cylinder head 12 when the valve is opened, and the valve opening degree is regulated.

  Reference numeral 20 denotes a seal member provided between the cylinder 5 and the valve seat member 15, and reference numeral 21 denotes a seal member provided between the cylinder head 12 and the valve seat member 15. The sealing member 20 hermetically seals the compression chamber 11, and the sealing member 21 hermetically seals the suction chamber 13 and the discharge chamber 14.

  The oscillating air compressor 1 according to the present embodiment has the above-described configuration. Next, the operation of the air compressor 1 will be described.

  First, when the crankshaft 3 is rotationally driven by the electric motor 4, the piston 6 reciprocates while swinging in the cylinder 5, so that the piston 6 is displaced downward and the piston 6 is displaced upward. The discharge process is repeated alternately.

  In this case, in the suction stroke, when a negative pressure is generated on the compression chamber 11 side, the suction valve 17 is opened to a position where it abuts on the suction valve receiver 18 by this negative pressure, and the discharge valve 19 is a cylinder of the valve seat member 15. It sits on the head side surface 15A and closes. As a result, the suction chamber 13 and the compression chamber 11 of the cylinder head 12 communicate with each other via the suction port 15C of the valve seat member 15, and external air passes through the suction chamber 13 from the suction port 12B of the cylinder head 12. It is sucked into the compression chamber 11.

  On the other hand, in the discharge stroke, the suction valve 17 is seated on the compression chamber side surface 15B of the valve seat member 15 and is closed. And if the pressure in the compression chamber 11 rises, the discharge valve 19 will open to the position which contact | abuts the discharge valve receptacle 12D of the cylinder head 12. FIG. As a result, the compression chamber 11 and the discharge chamber 14 of the cylinder head 12 communicate with each other via the discharge port 15D of the valve seat member 15, so that the compressed air in the compression chamber 11 is discharged from the discharge chamber 14 to the cylinder head 12. It is discharged outside through the outlet 12C and stored in an external air tank (not shown) or the like.

  In this discharge stroke, the piston 6 moves in the cylinder 5 from the bottom dead center to the top dead center, and the upper surface 8A of the retainer 8 is brought closest to the compression chamber side surface 15B of the valve seat member 15 at the position of the top dead center. The volume of the chamber 11 is minimized.

  Here, since the suction valve housing concave groove 16 is provided in the compression chamber side surface 15B of the valve seat member 15, and the suction valve 17 and the suction valve receiver 18 are housed in the suction valve housing concave groove 16, the retainer 8 of the piston 6 is retained. It is possible to flatten the compression chamber side surface 15B facing the surface. Thereby, the invalid gap G (top clearance) formed between the upper surface 8A of the retainer 8 and the compression chamber side surface 15B of the valve seat member 15 is reduced by the thickness dimension of the suction valve 17 and the suction valve receiver 18. Therefore, the amount of compressed air that cannot be discharged and remains in the compression chamber 11 and does not contribute to discharge can be reduced.

  Thus, according to the present embodiment, the valve seat member 15 that defines the compression chamber 11 with the piston 6 is provided with a suction valve housing recess on the flat compression chamber side surface 15B facing the retainer 8 of the piston 6. A groove 16 is provided. The suction valve housing concave groove 16 houses a suction valve 17 and a suction valve receiver 18 provided on the compression chamber side surface 15B. Thus, by accommodating the suction valve 17 and the suction valve receiver 18 in the suction valve housing recess groove 16, the suction valve housing recess groove 16 can be filled with the suction valve 17 and the suction valve receiver 18, and the valve seat member The 15 compression chamber side surfaces 15B can be made substantially flat.

  Therefore, since the suction valve and the suction valve receiver do not protrude from the compression chamber side surface 15B of the valve seat member 15 as described in the prior art, the retainer 8 of the piston 6 with respect to the flat compression chamber side surface 15B. The upper surface 8A can be as close as possible. That is, the gap G formed between the upper surface 8A of the retainer 8 and the compression chamber side surface 15B of the valve seat member 15 when the piston 6 is disposed at the top dead center can be set to the minimum.

  Further, since the suction valve accommodating groove 16 directly accommodates the suction valve 17 and the suction valve receiver 18, the dimensional tolerance considered when forming the suction valve accommodating concave groove 16 is the same as that of the suction valve 17. Only the dimensional tolerance of the suction valve receiver 18, and the suction valve housing groove 16 can be set to the minimum size necessary for air to flow.

  As a result, the volume of the compression chamber 11 when the piston 6 is disposed at the top dead center can be reduced, and the amount of compressed air remaining in the compression chamber 11 without being discharged can be reduced. The compression efficiency when the machine 1 is reciprocated can be improved.

  Further, since the suction valve receiving concave groove 16 accommodates the suction valve receiver 18 on the valve opening side of the suction valve 17, the opening degree when the suction valve 17 is opened during the suction stroke is regulated. Can do. Thereby, when switching from the suction stroke to the discharge stroke, the suction valve 17 can be quickly closed, so that loss due to the closing delay can be eliminated and the compression performance can be improved. Even when the suction valve receiver 18 is provided, as described above, the amount of compressed air remaining in the compression chamber 11 and not contributing to discharge can be reduced, and the compression efficiency can be improved.

  In the embodiment, the rod 9 is integrally formed with the piston 6 and the swing type air compressor 1 that reciprocates while swinging is described as an example. However, the present invention is not limited to this, and is applied to a reciprocating compressor in which a separately provided piston and rod are connected using a piston pin and the piston reciprocates in a cylinder in a parallel state. It is good.

  In the embodiment, the suction valve 17 is opened only when the compression chamber 11 becomes negative pressure, and air is sucked into the compression chamber 11 from the suction port 15 </ b> C of the valve seat member 15. However, the present invention is not limited to this, and an unload mechanism that forcibly opens the suction valve 17 in the cylinder head 12 may be provided. In this case, the load acting on the electric motor 4 at the start of operation can be reduced.

  Further, in the embodiment, the case where the suction valve 17 and the suction valve receiver 18 are housed in the suction valve housing concave groove 16 of the valve seat member 15 has been described as an example. However, the present invention is not limited to this, and the suction valve housing concave groove 16 may be formed as shallow as the plate thickness of the suction valve 17 to accommodate only the suction valve 17.

  On the other hand, in the embodiment, the case where the electric motor 4 is provided integrally with the crankcase 2 is illustrated. However, the present invention is not limited to this, and an electric motor may be provided separately from the crankcase, and the output shaft and the crankshaft may be connected via a pulley, a belt, or the like.

  Furthermore, in the embodiment, the reciprocating type air compressor 1 has been described as an example, but the present invention is not limited to the air compressor, and can be widely applied to, for example, a vacuum pump, a refrigerant compressor, and the like. .

It is sectional drawing which shows the rocking | swiveling type air compressor by embodiment of this invention. It is sectional drawing which looked at the air compressor from the arrow II-II direction in FIG. It is an expanded sectional view which expands and shows the cylinder, piston, cylinder head, valve seat member, suction valve, etc. in FIG. It is a disassembled perspective view which shows a cylinder head, a valve seat member, a suction valve, a suction valve receptacle, a discharge valve, etc.

Explanation of symbols

1 Air compressor (reciprocating compressor)
2 Crankcase 3 Crankshaft 5 Cylinder 6 Piston 7 Lip seal 8 Retainer 8A Upper surface 11 Compression chamber 12 Cylinder head 13 Suction chamber 14 Discharge chamber 15 Valve seat member 15A Cylinder head side surface 15B Compression chamber side surface 15C Suction port 15D Discharge port 16 Suction valve Housing concave groove 17 Suction valve 18 Suction valve receptacle 19 Discharge valve G Invalid gap between top dead center piston 6 and valve seat member 15

Claims (2)

A cylinder in which a piston is removably inserted, a cylinder head mounted at the tip of the cylinder, and a compression chamber provided between the cylinder head and the cylinder to define a compression chamber. A valve seat member having a suction port and a discharge port opening in the compression chamber; a suction valve provided in the valve seat member for opening and closing the suction port; and a discharge provided in the valve seat member for opening and closing the discharge port. In a reciprocating compressor comprising a valve,
The valve seat member forms a compression chamber side surface facing the piston on a flat surface,
And the valve seat member is provided with a suction valve housing concave groove located on the side of the compression chamber,
A reciprocating compressor characterized in that the suction valve accommodating concave groove accommodates the suction valve.   2. The reciprocating compressor according to claim 1, wherein the suction valve housing concave groove houses a suction valve receiver that regulates an opening degree of the suction valve so as to overlap an opening side of the suction valve.

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