JP2010090705A - Refrigerant compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerant compressor which provides high efficiency and reliability through the reduction of re-expansion loss and enhancement of the component strength thereof. <P>SOLUTION: In a highly efficient and reliable refrigerant compressor, a compression element for sucking and compressing refrigerant gas is accommodated in a sealed vessel. A compression chamber 143 which forces refrigerant gas of a compression element to be compressed is provided with: a cylinder block; a piston 117 which reciprocates in the compression chamber 143; and a valve plate 127 which seals an end surface of the cylinder block and has a discharge valve device 137 on anti-compression chamber 143 side. A protrusion 151 which consists of a truncated conical projection 147 and a cylindrical projection 149 continuous with the truncated conical projection 147 successively from the compression chamber side end surface 141 is provided on the compressed chamber side end surface 141 of the piston 117. A discharge port 139 having a shape corresponding to the protrusion 151 is formed in the valve plate 127. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a refrigerant compressor used in a refrigeration cycle such as a refrigerator-freezer.

  Conventionally, as this type of refrigerant compressor, a frustoconical protrusion is provided on the end surface of the piston on the compression chamber side, and a discharge port having a shape corresponding to the protrusion is provided on the valve plate. Some have reduced loss (see, for example, Patent Document 1).

  Hereinafter, the conventional refrigerant compressor will be described with reference to the drawings.

  FIG. 3 is a longitudinal sectional view showing the entire structure of a conventional refrigerant compressor described in Patent Document 1, and FIG. 4 is a sectional view of a main part of the compression element.

  3 and 4, a bearing for supporting a crankshaft 9 in which an electric element 3 and a compression element 5 are integrally formed with a crankpin 7 is placed in a sealed container 1 for storing lubricating oil (not shown). The compressor main body 15 arranged and arranged above and below the frame 13 having 11 is suspended and accommodated via an elastic body (not shown) such as a spring.

  The crankpin 7 is formed eccentric to a crankshaft 9 that is press-fitted and fixed to a rotor 19 that constitutes the electric element 3.

  The piston 21 is inserted into a substantially cylindrical cylinder block 23 so as to be slidable back and forth, and is connected to the crankpin 7 by connecting means (not shown).

  A valve plate 27 that seals the opening end face of the cylinder block 23 includes a suction port (not shown) that communicates with the cylinder block 23 by opening and closing a suction valve (not shown), a discharge valve 29 and a discharge valve seat 31. A discharge port 35 communicating with the cylinder block 23 is provided by opening and closing the discharge valve device 33, and a compression chamber 39 is defined by the cylinder block 23, the top surface 37 of the piston 21, and the valve plate 27.

  A cylinder head 41 forming a high pressure chamber (not shown) is fixed to the opposite side of the cylinder block 23 via a valve plate 27.

  The top surface 37 of the piston 21 has a frustoconical protrusion 43, and the protrusion 43 and the discharge port 35 have a substantially corresponding shape.

  The operation of the refrigerant compressor configured as described above will be described below.

  When the crankshaft 9 formed integrally with the crankpin 7 is rotationally driven by the electric element 3, the piston 21 reciprocates in the cylinder block 23 via a connecting means (not shown) due to the eccentric movement of the crankpin 7. Then, the suction, compression, and discharge processes are sequentially repeated.

In the discharge stroke of the piston 21, the compressed refrigerant gas (not shown) in the compression chamber 39 passes through the discharge port 35 and is discharged to the high pressure chamber (not shown) by opening and closing the discharge valve device 33. . At this time, at the top dead center of the piston 21, the refrigerant gas remaining in the discharge port 35 is re-expanded in the next intake stroke, so that the amount of refrigerant gas to be sucked is reduced and lost. However, since the protrusion 43 enters the discharge port 35, the amount of refrigerant gas remaining in the discharge port 35 is very small, and the loss due to re-expansion is small.
Japanese Patent No. 3082867

  However, the above-described conventional configuration has a problem that the portion of the discharge port 35 of the valve plate 27 that forms the discharge valve seat 31 side has an acute-angle shape and lacks strength and has a risk of chipping.

  The present invention solves the above-mentioned conventional problems. Since the protrusion 43 enters the discharge port 35 at the top dead center of the piston 21, the amount of refrigerant gas remaining in the discharge port 35 is very small, and the re-expansion is performed. It is an object of the present invention to provide a highly reliable refrigerant compressor that has low loss, high efficiency, sufficient strength, and high reliability.

  In order to solve the above-described conventional problems, a refrigerant compressor according to the present invention includes a cylindrical projection that is continuous with a truncated cone-shaped projection and a truncated cone-shaped projection on the compression chamber-side end surface of the piston in order from the compression chamber-side end surface. In addition, the valve plate has a discharge port having a shape corresponding to the protrusion of the piston on the valve plate. Therefore, the refrigerant gas remaining in the discharge port because the protrusion enters the discharge port at the top dead center of the piston. The amount of this is very small and the loss due to re-expansion is small, and the portion forming the discharge valve seat side of the discharge port of the valve plate has a substantially right-angled shape and has a sufficient strength.

  The refrigerant compressor of the present invention has a convex portion formed of a truncated cone-shaped projection and a cylindrical projection continuous to the truncated cone-shaped projection in order from the compression chamber-side end surface on the compression chamber-side end surface of the piston, and a valve Since the plate has a discharge port with a shape corresponding to the convex part of the piston, the convex part enters the discharge port at the top dead center of the piston, so the amount of refrigerant gas remaining in the discharge port is negligible and loss due to re-expansion Since the portion forming the discharge valve seat side in the discharge port of the valve plate is substantially perpendicular and has sufficient strength, a highly efficient and reliable refrigerant compressor can be provided.

  According to a first aspect of the present invention, lubricating oil is stored in an airtight container, an electric element having a stator and a rotor, and a compression element driven by the electric element are accommodated, and the compression element is a cylinder. A cylinder block having a compression chamber, a piston that reciprocates in the compression chamber, and a valve plate that seals an end surface of the cylinder block and includes a discharge valve device on the non-compression chamber side. The end surface of the compression chamber has a convex portion formed of a truncated cone-shaped projection and a cylindrical projection continuous to the truncated cone-shaped projection in order from the compression chamber-side end surface. Since the discharge port having the corresponding shape is provided, a highly efficient and reliable refrigerant compressor can be provided.

(Embodiment 1)
FIG. 1 is a longitudinal sectional view of a refrigerant compressor in Embodiment 1 of the present invention, and FIG. 2 is a sectional view of essential parts in the same embodiment.

  1 and 2, a sealed container 101 is provided with a suction pipe 102, stores a lubricating oil 103 at the bottom, and compresses a compression element 105 for sucking and compressing refrigerant gas (not shown). A compressor main body 113 composed of an electric element 111 composed of a rotor 107 and a stator 109 for driving the element 105 is supported and accommodated via an elastic body 115 such as a spring.

  The piston 117 is inserted into a substantially cylindrical cylinder block 119 so as to be slidable in a reciprocating manner, and is connected to the crank pin 121 by a connecting rod 123 which is a connecting means.

  The crankpin 121 is formed eccentrically on a crankshaft 125 that is press-fitted and fixed to the rotor 107.

  The valve plate 127 that seals the opening end surface of the cylinder block 119 is opened and closed to open and close the discharge valve device 137 including the intake port 131, the discharge valve 133, and the discharge valve seat 135 that communicate with the cylinder block 119. A discharge port 139 communicating with the block 119 is provided, and a compression chamber 143 is defined by the cylinder block 119, the compression chamber side end surface 141 of the piston 117, and the valve plate 127.

  A cylinder head 145 forming a high pressure chamber (not shown) is fixed to the opposite side of the cylinder block 119 via a valve plate 127.

  On the compression chamber side end surface 141 of the piston 117, there is a convex portion 151 composed of a truncated cone-shaped projection 147 and a cylindrical projection 149 continuous with the truncated cone-shaped projection 147 in order from the compression chamber-side end surface 141, and a valve plate. The discharge port 139 of 127 has a shape corresponding to the convex portion 151 of the piston 117.

  The operation and action of the refrigerant compressor configured as described above will be described below.

  When the crankshaft 125 is rotationally driven by the rotation of the rotor 107 of the electric element 111, the piston 117 reciprocates in the cylinder block 119 via the connecting rod 123 by the eccentric movement of the crankpin 121, and performs a predetermined compression operation. Do.

  In the discharge stroke of the piston 117, the compressed refrigerant gas (not shown) in the compression chamber 143 passes through the discharge port 139 and is discharged to the high pressure chamber (not shown) by opening and closing the discharge valve device 137. .

  At this time, in the initial stage of opening and closing of the discharge valve device 137 where the flow rate of the refrigerant gas (not shown) discharged through the discharge port 139 is large, the refrigerant gas flow passage cross-sectional area of the discharge port 139 is large and the flow rate becomes small. , The convex portion 151 formed by the truncated cone-shaped protrusion 147 and the cylindrical protrusion 149 formed in order from the compression chamber side end surface 141 of the piston 117 enters the discharge port 139, so that the refrigerant gas flow path cross-sectional area of the discharge port 139 Is gradually reduced, the discharge efficiency of the compressed refrigerant gas is good, and the efficiency of the refrigerant compressor is high.

  At that time, at the top dead center of the piston 117, the refrigerant gas remaining in the discharge port 139 is re-expanded in the next intake stroke, so that the amount of refrigerant gas to be sucked is reduced and lost. However, on the compression chamber side end surface 141 of the piston 117, a convex portion 151 including a truncated cone-shaped projection 147 and a cylindrical projection 149 continuous with the truncated cone-shaped projection 147 in order from the compression chamber-side end surface 141 is a discharge port 139. Therefore, the amount of refrigerant gas remaining in the discharge port 139 is very small, loss due to re-expansion is small, and the efficiency of the refrigerant compressor is high.

  Further, the portion of the discharge port 139 of the valve plate 127 forming the discharge valve seat 135 side has a substantially right-angled shape and has sufficient thickness and strength, so that the refrigerant compressor has high reliability.

  As described above, the refrigerant compressor according to the present invention can prevent the vortex flow of the refrigerant gas inside the suction muffler, and can smooth the flow of the refrigerant gas, so that the suction efficiency is improved. Since it becomes possible to provide a highly efficient refrigerant compressor, it can also be used for applications such as an air conditioner and a refrigerant compressor of a refrigeration refrigerator.

The longitudinal cross-sectional view of the refrigerant compressor in Embodiment 1 of this invention Cross-sectional view of the main part in the same embodiment A longitudinal sectional view showing the overall structure of a conventional refrigerant compressor Sectional view of the main part of a conventional compression element

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Sealed container 103 Lubricating oil 105 Compression element 107 Rotor 109 Stator 111 Electric element 117 Piston 119 Cylinder block 127 Valve plate 137 Discharge valve device 139 Discharge port 141 Compression chamber side end surface 143 Compression chamber 147 Frustum-shaped protrusion 149 Cylindrical shape Projection 151 Projection

Claims (1)

A cylinder block that stores lubricating oil in an airtight container, and stores an electric element including a stator and a rotor and a compression element driven by the electric element, and the compression element includes a cylindrical compression chamber. A piston that reciprocates in the compression chamber, and a valve plate that seals an end surface of the cylinder block and includes a discharge valve device on the non-compression chamber side, and the compression chamber side end surface of the piston In addition to having a convex portion composed of a truncated cone-shaped projection and a cylindrical projection continuous to the truncated cone-shaped projection in order from the chamber side end surface, the valve plate has a discharge port having a shape corresponding to the convex portion. A refrigerant compressor characterized by

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