JP2005214080A - Reciprocating machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reciprocating machine such as a reciprocating compressor capable of reducing clearance displacement and increasing volume efficiency. <P>SOLUTION: A storage recessed part 17 storing an intake valve 5 or an intake valve receiver 6 is formed in the upper end face 9A of a piston 9. A piston ring 11 is formed so that its upper end face 11E extends to the upper side of a piston ring groove 10. A piston ring recessed part 11C is formed in the side face of the piston ring 11 opposed to the storage recessed part 17. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a reciprocating machine such as a reciprocating compressor and a vacuum pump, and more particularly to a reciprocating machine improved to increase volumetric efficiency.

  In reciprocating machines, various configurations for reducing the clearance volume have been developed in order to improve volumetric efficiency. For example, Patent Document 1 discloses a location facing the suction valve receiver on the upper end surface of the piston in order to reduce the gap volume formed between the valve seat member and the top of the piston when the piston reaches top dead center and increase the compression efficiency. A configuration for mounting a required number of thin plates is disclosed.

  Patent Document 2 discloses a configuration in which the piston ring is formed so as to be flush with the upper end surface of the piston, and the gap between the upper end outer periphery of the piston and the inner peripheral surface of the cylinder is closed.

Japanese Utility Model Publication No. 57-136875

JP 61-215474 A

  Here, in order to further improve the volumetric efficiency, when the piston ring is extended to the piston upper end surface as shown in Patent Document 2 in the above-described piston of Patent Document 1, when the piston reaches the top dead center, the piston has a suction valve. Although there is a concave groove at a position facing the receiver, the piston ring exists up to a position that is flush with the upper end surface of the piston, so that the suction valve or the end of the suction valve receiver collides with the piston ring. Therefore, there is a problem that a clearance volume formed between the upper end surface of the piston and the cylinder head located at a position facing the upper end surface of the piston is increased.

  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 provide a reciprocating machine such as a reciprocating compressor that further reduces the clearance volume and improves the volume efficiency. It is in.

  In order to solve the above-described problems, the present invention provides a cylinder, a cylinder head provided so as to cover the upper end surface of the cylinder, a suction port provided in the cylinder head, and the suction port is closed or opened. Therefore, a suction valve fixed to the cylinder head, a piston slidably fitted in the cylinder, and a piston ring formed on a side surface of the piston to seal between the piston and the cylinder In a reciprocating machine comprising a piston ring fitted in a groove and a discharge port connected to the inside of the cylinder and having a discharge valve, an upper surface of the piston opens to a side surface of the piston, and the suction valve is A storage recess for storing is provided, and the piston ring is configured such that an upper end surface thereof extends upward from a side opening of the storage recess, and the piston ring includes the piston ring. Characterized in that the formation of the piston ring recess for storing the suction valve side opening opposed to the position of the stowage recess tons.

  The invention of claim 2 is a cylinder, a cylinder head provided so as to cover the upper end surface of the cylinder, a suction port provided in the cylinder head, and the cylinder for closing or opening the suction port. A suction valve fixed to the head, a suction valve receiver for receiving the suction valve, a piston slidably inserted in the cylinder, and a side surface of the piston for sealing between the piston and the cylinder In a reciprocating machine consisting of a piston ring fitted in a piston ring groove formed in a cylinder and a discharge port connected to the inside of the cylinder and having a discharge valve, an opening is formed on the upper surface of the piston on a side surface of the piston. A storage recess for storing the suction valve receiver, and the piston ring is configured such that an upper end surface of the piston ring extends above a side opening of the storage recess, The Nringu, characterized in that the formation of the piston ring recess for storing the suction valve received in a position to a side opening facing the storage recess of the piston.

  According to a third aspect of the present invention, in the reciprocating machine according to the first and second aspects, the upper surface of the piston is provided with a fitting recess that opens to a side surface of the piston, and the piston ring includes the piston of the piston. A piston ring convex portion that fits into the fitting concave portion is provided.

  According to a fourth aspect of the present invention, in the reciprocating machine according to the third aspect of the invention, the storage recess of the piston is opened at both ends on the side surface of the piston, and one end side of the storage recess is used as the fitting recess. The piston ring convex portion extends in a gap formed by the storage concave portion of the piston and the suction valve or the suction valve receiver when the piston reaches top dead center.

  In the invention according to claim 1, when the piston reaches the top dead center, the piston, the piston in a position where the piston ring and the suction valve collide, the piston ring upper end surface, the storage recess, the piston ring recess, respectively. The piston ring does not collide with the suction valve or the end of the suction valve receiver. Therefore, the clearance volume formed between the upper end surface of the piston and the cylinder head at the position facing the upper end surface of the piston can be reduced, and the volume efficiency can be improved.

  According to the invention of claim 2, in a reciprocating machine having a suction valve receiver, a storage recess and a piston ring recess are respectively formed in the piston and the piston ring at the position where the suction valve receiver collides as in the case of claim 1. Therefore, the piston ring does not collide with the suction valve or the end of the suction valve receiver. Therefore, the clearance volume formed between the upper end surface of the piston and the cylinder head at the position facing the upper end surface of the piston can be reduced, and the volume efficiency can be improved.

  In the invention of claim 3, since the fitting concave portion is formed in the piston and the piston ring convex portion to be fitted to the fitting concave portion is provided, the operation of reciprocating the piston in the cylinder is repeated. Thus, it is possible to reliably prevent the piston ring from rotating in the radial direction and the storage recess from being displaced from the piston ring recess. Therefore, the storage recess and the piston ring recess are displaced, so the end of the suction valve or the suction valve receiver is not stored, and the problem that the piston ring collides with the suction valve or the end of the suction valve receiver can be solved. In addition, the volumetric efficiency can be improved by reducing the clearance volume.

  In the invention of claim 4, since the piston ring convex portion is configured to fill the gap between the storage concave portion and the suction valve or the suction valve receiver, the clearance efficiency can be further reduced to improve the volume efficiency. it can.

  Hereinafter, in the embodiment of the present invention, a reciprocating compressor will be described as an example of a reciprocating machine.

  1 to 5 show a first embodiment of the present invention. FIG. 1 is a cross-sectional view of an essential part showing a reciprocating compressor according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of a cylinder alone when the cylinder 1 of FIG. 3 is a piston single unit external view of the piston 9 of FIG. 1 viewed from the B direction, and FIG. 4 is a single piston unit external view of the piston 9 of FIG. 3 viewed from the C direction. FIG. 5 is a single perspective view of the piston ring 11 of FIG.

  The reciprocating compressor shown in the drawing is for closing or opening the cylinder 1, the cylinder head 2 provided so as to cover the cylinder 1, the suction port 3A provided in the cylinder head 2, and the suction port 3A. A suction valve 5 and a suction valve receiver 6 fixed to the cylinder head 2, a piston 9 slidably fitted in the cylinder 1, and a piston 9 for sealing between the piston 9 and the cylinder 1. And a piston ring 11 fitted on the outer periphery of the main body.

  Hereinafter, each configuration will be described in detail.

  In FIG. 1, reference numeral 1 denotes a cylinder mounted on a crankcase (not shown). The cylinder 1 is formed as a cylindrical body extending in the vertical direction in FIG. 1A shows an engagement step portion formed on the inner wall of the cylinder 1, and the engagement step portion 1A is provided at the upper end of the inner wall of the cylinder 1 to lock the suction valve receiver 6, and has a groove shape recessed in the axial direction. It has become. A storage portion 1B that stores the proximal end side of the suction valve receiver 6 and the suction valve 5 is provided at a position facing the engagement step portion 1A in the radial direction. As shown in FIG. 2, only the engagement step portion 1A and the storage portion 1B are provided in the upper end portion of the cylinder 1 with a recess in the axial direction.

  Reference numeral 2 denotes a cylinder head provided so as to cover the upper end surface 1C of the cylinder 1. The cylinder head 2 has a flat valve seat member 3 having a suction port 3A and a discharge port 3B, a suction chamber 4A, and a discharge chamber 4B. The suction / discharge chamber forming member 4 is formed. The suction / discharge chamber forming member 4 is provided with a suction port 4C for taking outside air into its outer wall and a discharge port 4D for discharging the generated compressed air to a tank (not shown). Yes.

  Reference numeral 5 denotes a suction valve provided between the valve seat member 3 and the suction valve receiver 6. The suction valve 5 is made of a steel material having a spring property, and the cylinder 1 is moved from the engagement step portion 1A to the storage portion 1B. It is provided so as to cross the inner circumference. The suction port 3A is opened and closed by seating on the lower surface side of the valve seat member 3 according to the reciprocating motion of the piston 9 in the cylinder 1, and only the air flow from the suction chamber 4A into the cylinder 1 is allowed. . The lift amount (opening degree) of the suction valve 5 when the valve is opened is regulated by the suction valve receiver 6. The shape of the suction valve 5 is preferably a reed valve or a lift valve that can be simply structured.

  Reference numeral 6 denotes an elongated suction valve receiver that is located in the cylinder 1 and is disposed on the lower surface side of the valve seat member 3. The suction valve receiver 6 has a base end side on the lower surface side of the valve seat member 3. The suction valve 5 is fixed together with the screw 6 </ b> A, and the front end side is bent downward in two stages so as to be separated from the lower surface of the valve seat member 3. Similarly to the suction valve 5, the suction valve receiver 6 is made of a steel material having a spring property, and is provided so as to cross the inner periphery of the cylinder 1 from the engaging step portion 1A to the storage portion 1B. The suction valve receiver 6 is locked at its distal end by an engaging step 1 </ b> A formed on the inner wall of the cylinder 1. The suction valve receiver 6 is provided to prevent the suction valve 5 from being damaged when the suction valve 5 is in direct contact with the locking portion 1A or the piston 9. It is desirable to form with the material which has hardness more than that. Further, the shape of the suction valve receiver 6 is desirably a plate-like member having a size equal to or larger than that of the suction valve 5 for the reason described above. In addition, if it is so hard that it does not deform | transform, the engagement to 1 A of engagement step parts is unnecessary.

  Reference numeral 7 denotes a discharge valve located in the discharge chamber 4B and provided between the valve seat member 3 and the discharge valve receiver 8. The discharge valve 7 is formed in a long thin plate. Further, the discharge valve 7 has a spring property, and opens and closes the discharge port 3B by being separated from and seated on the upper surface side of the valve seat member 3 in accordance with the reciprocating motion of the piston 9 in the cylinder 1 to discharge from the inside of the cylinder 1. It operates to allow only air flow to the chamber 4B. The lift amount of the discharge valve 7 when the valve is opened is regulated by the discharge valve receiver 8. The discharge valve receiver 8 is located in the discharge chamber 4 </ b> B similarly to the discharge valve 7 and is disposed on the upper surface side of the valve seat member 3, and the base end side is fixed to the upper surface side of the valve seat member 3 with screws 8 </ b> A. Further, the discharge valve receiver 8 is bent upward so that the distal end side is separated from the upper surface of the valve seat member 3.

  Reference numeral 9 denotes a piston that is slidably inserted into the cylinder 1 and is divided into an upper chamber (compression chamber 18) and a lower chamber. On the outer peripheral side of the piston 9, as shown in FIG. A ring groove 12 is formed, and a piston ring 11 and a rider ring 13 are fitted in each groove, and each outer peripheral surface is in sliding contact with the inner peripheral surface of the cylinder 1. The piston 9 is connected to a crankshaft (not shown) via a connecting rod 14, a piston pin 15, and a small end bearing 16, and the crankshaft is driven to rotate to move the inside of the cylinder 1 up and down in FIG. Reciprocates in the direction.

  Reference numeral 11 denotes a piston ring mounted in the piston ring groove 10 of the piston 9, and the piston ring 11 is formed of a material having self-lubricating properties such as polytetrafluoroethylene and carbon material. Further, the piston ring 11 is fitted to the piston ring groove 10 with a reduced diameter so that there is no leakage of compressed air from the upper chamber (compression chamber 18) of the piston 9 to the lower chamber.

  Next, the shape of the piston ring 11 will be described in detail with reference to FIG. The piston ring 11 includes an annular thick part 11A fitted in the piston ring groove 10 and a thin part 11B provided so as to extend upward from the outer periphery of the thick part 11A. The thin wall portion 11B has an upper end surface 11E extending axially upward from the piston ring groove 10 along the outer periphery 9B to the vicinity of the upper end portion of the piston 9, and the upper end outer periphery 9B of the piston 9 and the inner peripheral surface of the cylinder 1 It is comprised so that the annular space between may be closed substantially. The piston ring 11 is formed with a piston ring recess 11 </ b> C having the same shape as the one end 17 </ b> A of the storage recess 17 on the side surface facing the end 17 </ b> A of the storage recess 17. The piston ring 11 has a circular shape with one cut, and the joint portion 11D is formed in a step shape so as to overlap each other and form a perfect circle. When the piston ring 11 receives a back pressure due to the pressure of the compression chamber 18, the mating portion 11 </ b> D further expands in diameter, and the pressing force to the cylinder 1 is increased. Further, the piston ring 11 is configured so that the piston ring 11 width is slightly larger than the piston ring groove 10 width in order to prevent the piston 9 from rotating in the radial direction while repeatedly reciprocating in the cylinder 1. ing.

  Reference numeral 17 denotes a storage recess formed on the upper end surface 9A of the piston 9. The storage recess 17 is slightly larger than the suction valve receiver 6 at the substantially central portion of the upper end surface 9A of the piston 9 as shown in FIGS. A groove is formed, and both ends 17 </ b> A and 17 </ b> B are configured to open to the side surface of the piston 9 in the length direction of the groove. Moreover, the storage recessed part 17 is shape | molded by the groove shape by scraping the center part of 9 A of upper end surfaces of the piston 9 using machining.

  The reciprocating compressor according to the present embodiment has the above-described configuration, and the operation thereof will be described next.

  When a crankshaft (both not shown) is rotationally driven by a motor or the like, the piston 9 reciprocates in the vertical direction within the cylinder 1. In the suction stroke, when the piston 9 starts to move downward, the suction valve 5 is opened, and external air is sucked into the cylinder 1 in the order of the suction port 4C, the suction chamber 4A, and the suction port 3A. Thereafter, in the compression stroke, the piston 9 moves upward, so that the air in the cylinder 1 is compressed. When the pressure in the cylinder 1 exceeds the pressure in a tank (not shown) connected to the discharge chamber 4A, the discharge valve 7 is opened, and this compressed air is discharged into the discharge port 3B, the discharge chamber 4B, and the discharge port. It is discharged into the tank through 4D.

  In the embodiment of the present invention, an annular thin portion 11B is extended on the piston ring 11 so as to block between the upper end outer periphery 9B of the piston 9 and the inner peripheral surface of the cylinder 1, and the upper end surface of the thin portion 11B. Is disposed so as to be substantially flush with the upper end surface 9A of the piston 9, the compressed air compressed in the cylinder 1 is formed between the inner peripheral surface of the cylinder 1 and the upper end outer periphery 9B of the piston 9. It is possible to eliminate the possibility of staying in between. Further, since the suction valve receiver 6 is stored in the storage recess 17 and the piston ring recess 11C when the piston 9 reaches the top dead center, the top dead center of the piston 9 can be designed higher. Therefore, the discharge amount of compressed air can be increased, the clearance volume can be reduced, and the volume efficiency can be improved.

  Next, a second embodiment according to the present invention will be described with reference to FIGS. FIG. 6 is a cross-sectional view of an essential part showing a reciprocating compressor according to a second embodiment of the present invention, and FIG. 7 is a perspective view showing a single unit of a piston ring 19 according to the second embodiment. The feature of the embodiment of the present invention is that when the piston 9 reciprocates in the cylinder 1, the piston ring 19 reliably prevents the piston ring 19 from rotating in the piston ring groove 11A provided in the piston 9 in the radial direction. As a detent, the piston ring convex portion 19 </ b> A fitted in the storage concave portion 17 as the fitting concave portion formed in the piston 9 is configured. In the embodiment of the present invention, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The convex portion 19 </ b> A of the piston ring 19 is provided to be fitted to the other end 17 </ b> B of the storage concave portion 17 of the upper end surface 9 </ b> A of the piston 9. Further, a piston ring concave groove 11C is provided on the side surface of the piston ring 19 facing the one end 17A of the storage concave portion 17 as in the first embodiment.

  As a result, when the piston 9 reciprocates in the cylinder 1 in the vertical direction, the piston ring 19 rotates in the piston ring groove 11A, and the one end 17A of the storage recess 17 and the piston ring recess 11C are reliably prevented from being displaced, The suction valve receiver 6 can be securely stored in the storage recess 17 and the piston ring recess 11C.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. Furthermore, in the embodiment of the present invention, it is possible to reliably prevent the piston ring 19 from rotating when the piston 9 reciprocates in the cylinder 1, and the storage recess 17 and the piston ring recess 11C are always provided. Since they are fixed so as to face each other, it is possible to eliminate the problem that the suction valve receiver 6 is not stored in the storage recess 17 and the piston ring recess 11C and the piston 9 cannot reach the top dead center. Therefore, the clearance volume can be reliably reduced and the volume efficiency can be improved.

  In the embodiment of the second invention, both ends of the storage recess 17 of the piston 9 are opened. However, the present invention is not limited thereto, and only one end is opened, and the suction valve 5 or the suction valve receiver is provided there. 6 may be stored, and the piston ring convex portion 19A may be provided on both sides of the piston ring concave portion 11C so as to be fitted into the opening. Alternatively, a piston ring convex portion 19A extending from the bottom of the piston ring concave portion 11C toward the inner periphery may be provided and fitted into the opening.

  Next, a third embodiment according to the present invention will be described with reference to FIGS. FIG. 8 is a cross-sectional view of an essential part showing a reciprocating compressor according to a third embodiment of the present invention, and FIG. 9 is a perspective view showing a single unit of a piston ring 20 according to the third embodiment. The feature of the present embodiment is that, as in the second embodiment, the piston ring is provided with a convex portion for preventing rotation, and the convex portion is filled with a gap between the suction valve receiver 6 and the storage concave portion 17. The gap filling member is used. In the embodiment of the present invention, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  Reference numeral 20 denotes a piston ring having a convex portion 20A on the inner surface. The piston ring 20 is fitted so as to close a gap formed between the storage concave portion 17 of the upper end surface 9A of the piston and the proximal end side of the suction valve receiver 6. Are provided. Since the base end side of the suction valve receiver 6 shown in the embodiment of the present invention extends in the horizontal direction and thereafter has a two-step inclined portion, the piston ring convex portion 20A also extends in the horizontal direction in accordance with the shape. Then, the shape is inclined as it goes to the inner periphery. Further, a piston ring concave groove 11C is provided on the side surface of the piston ring 20 facing the one end 17A of the storage concave portion 17 as in the embodiment of the first invention.

  As a result, when the piston 9 reciprocates in the cylinder 1 in the vertical direction, not only the piston ring 20 is prevented from rotating in the piston ring groove 10, but also the clearance volume can be reliably reduced.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. Furthermore, in the embodiment of the present invention, the gap between the lower surface of the suction valve receiver 6 and the storage recess 17 can be filled with the convex portion 20A for preventing rotation, so that the clearance volume can be further reduced. , Volume efficiency can be improved.

  Further, in the second and third embodiments of the present invention, the example in which the storage concave portion 17 of the piston 9 is shared as the fitting concave portion into which the piston ring convex portion 19A is fitted is shown. The fitting recess formed in 9 is open on the upper surface of the piston 9 and on the side surface of the piston 9, and the piston ring protrusion 19A may be provided at a position facing the opening.

  In the above-described embodiments of the present invention, the reciprocating compressor has been described as an example of the reciprocating machine. However, the present invention is not limited to this and may be applied to a reciprocating vacuum pump.

  In the embodiments of the present invention, the reciprocating machine having the suction valve receiver 6 has been described as an example. However, the invention may be applied to a reciprocating machine having only the suction valve 5 having no suction valve receiver 6. . Also when comprised in this way, the suction valve 5 can be stored in the storage recessed part 17 and the piston ring recessed part 11C, and a clearance volume can be made small.

  Further, in each of the embodiments of the present invention, an example is shown in which the suction valve 5 and the suction valve receiver 6 are stored together in the storage recess 17 formed in the piston 9 when the piston is located near the top dead center. However, the groove depth of the storage recess 17 may be set so as to store only the suction valve receiver 6 without being limited thereto.

  In the embodiments of the above inventions, the method of forming the storage recess 17 has been shown by shaving. However, the present invention is not limited to this, and it is formed by pasting a half-moon shaped thin plate as shown in Prior Art Document 1. May be.

It is principal part sectional drawing which shows the reciprocating compressor by the 1st Embodiment of this invention. It is AA sectional drawing of the cylinder 1 single-piece | unit shown in FIG. It is the external view which looked at the piston 9 simple substance shown in FIG. 1 from the B direction. It is the external view which looked at the piston 9 single-piece | unit of FIG. 3 from C direction. It is a perspective view of the piston ring single-piece | unit of the 1st Embodiment of this invention. It is principal part sectional drawing which shows the reciprocating compressor by the 2nd Embodiment of this invention. It is a perspective view of the piston ring single-piece | unit of the 2nd Embodiment of this invention. It is principal part sectional drawing which shows the reciprocating compressor by the 3rd Embodiment of this invention. It is a perspective view of the piston ring single-piece | unit of the 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylinder 1C Upper end surface of a cylinder 2 Cylinder head 3 Valve seat member 3A Suction port 3B Discharge port 4 Suction / discharge chamber forming member 5 Suction valve 6 Suction valve receiver 9 Piston 11, 19, 20 Piston ring 11C Piston ring recess 17 Storage recess 19A, 20A Piston ring convex part

Claims (4)

A cylinder,
A cylinder head provided to cover the upper end surface of the cylinder;
A suction port provided in the cylinder head;
A suction valve secured to the cylinder head for closing or opening the suction port;
A piston slidably inserted in the cylinder;
A piston ring fitted in a piston ring groove formed on a side surface of the piston to seal between the piston and the cylinder;
A discharge port connected to the cylinder and having a discharge valve;
In a reciprocating machine consisting of
The upper surface of the piston is provided with a storage recess that opens to the side surface of the piston and stores the suction valve;
The piston ring is configured such that its upper end surface extends upward from the side opening of the storage recess,
A reciprocating machine characterized in that a piston ring recess for storing the suction valve is formed in the piston ring at a position facing a side opening of a storage recess of the piston. A cylinder,
A cylinder head provided to cover the upper end surface of the cylinder;
A suction port provided in the cylinder head;
A suction valve fixed to the cylinder head for closing or opening the suction port, and a suction valve receiver for receiving the suction valve;
A piston slidably inserted in the cylinder;
A piston ring fitted in a piston ring groove formed on a side surface of the piston to seal between the piston and the cylinder;
A discharge port connected to the cylinder and having a discharge valve;
In a reciprocating machine consisting of
The upper surface of the piston is provided with a storage recess that opens to the side surface of the piston and stores the suction valve receiver,
The piston ring is configured such that its upper end surface extends upward from the side opening of the storage recess,
A reciprocating machine characterized in that a piston ring recess for storing the suction valve receiver is formed in the piston ring at a position facing a side opening of a storage recess of the piston.   2. The upper surface of the piston is provided with a fitting recess that opens to a side surface of the piston, and the piston ring is provided with a piston ring convex portion that fits with the fitting recess of the piston. 2. A reciprocating machine according to 2. Both ends of the storage recess of the piston are opened on the side surfaces of the piston, and one end side of the storage recess is used as the fitting recess, and the piston ring protrusion is formed when the piston reaches top dead center. The reciprocating machine according to claim 3, wherein the reciprocating machine is extended in a gap formed by a storage recess and the suction valve or the suction valve receiver.

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