JPH0676662U - Reciprocating gas compressor - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a reciprocating gas compressor which prevents the D-ring from sticking to the wall surface of the cylinder and prevents the intake noise from becoming high. [Structure] A reciprocating gas compressor has a piston main body having an outer diameter substantially equal to the inner diameter of a cylinder and having a hollow portion serving as an intake passage, and a ring mounting groove connected to the crown of the piston main body and on the outer peripheral portion. A piston crown portion having a piston comprising a piston crown portion having an intake hole extending radially through a peripheral wall of the piston crown portion and connecting a hollow portion of the piston body and a ring mounting groove; A rubber elastic seal ring that is mounted in the mounting groove and cooperates with the bottom of the ring mounting groove to form an intake valve is included. The piston crown portion has an outer diameter smaller than the outer diameter of the piston body, and does not allow the outer peripheral portion of the rubber elastic seal ring in the state where the intake valve is open to contact the wall surface of the cylinder.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a reciprocating gas compressor.

[0002]

[Prior art]

 A conventional reciprocating gas compressor developed by the applicant is shown in FIG. This reciprocating gas compressor includes a piston 102 that is reciprocally mounted in a cylinder 101, and a discharge chamber block 103 that is arranged at the upper end of the cylinder 101. In the peripheral wall 104a of the piston 101, a plurality of intake ports 105 are formed at regular angular intervals in the circumferential direction of the peripheral wall 104 of the piston 101, and penetrate the peripheral wall 104 in the radial direction of the piston 101.

An annular ring mounting groove 106 having a V-shaped bottom surface is formed at a portion where the intake port 105 opens at the outer peripheral portion of the piston 101. A rubber elastic seal ring (hereinafter referred to as a D ring) 107 having a D-shaped cross section is mounted in the ring mounting groove 106. In this case, the curved portion of the D-shaped section is attached to and detached from the V-shaped bottom surface of the D-ring mounting groove 106. In this way, the intake valve 109 is constituted by the D ring 107 and the V-shaped bottom surface of the ring mounting groove 106.

The atmosphere is introduced into the compression chamber 110 formed in the cylinder 101 above the piston 104 through the hollow portion 108 inside the piston 104 and the intake valve 109. The intake valve 109 has a D-ring 107 when the compression chamber 110 is in a negative pressure state (that is, the atmospheric pressure in the hollow portion 108 of the piston 104 is higher than the internal pressure of the compression chamber 110) during the stroke of the piston 102 descending. It is open against the elasticity of. On the other hand, in the intake valve 109, when the internal pressure of the compression chamber 110 is higher than the atmospheric pressure in the hollow portion 108 in the process of the piston 102 rising, the differential pressure between the hollow portion 108 and the compression chamber 110 and the elastic force of the D ring 107. It is in a closed state by.

When the piston 102 rises and the internal pressure of the compression chamber 110 exceeds a certain pressure, the discharge reed valve 111 opens, and compressed air passes from the compression chamber 110 through the discharge port 112 at the crown of the cylinder 101, It is discharged to the discharge chamber 113 in the discharge chamber block 103. The compressed air in the discharge chamber 113 is sent to an accumulator (not shown) through the outlet 114.

[0006]

[Problems to be solved by the device]

 Since the reciprocating gas compressor repeatedly compresses air, both the piston 102 and the cylinder 101 are heated to a considerable temperature, and the D ring 107 is also thermally affected and softened as the temperature rises. As a result, when the piston 104 descends, the internal pressure of the compression chamber 110 becomes a negative pressure, and when the intake valve 109 opens, the D ring 107 expands in diameter and comes into contact with the wall surface of the cylinder 101 and becomes fixed. is there. At this time, since the piston 104 is descending, the D ring 107 is sandwiched between the outer peripheral surface of the piston 104 and the wall surface of the cylinder 101, and the effective sectional area of the air passage from the intake port 105 to the compression chamber 110 is reduced. To do. For this reason, the flow velocity of the air passing through this air passage increases, and the intake noise increases. An object of the present invention is to provide a reciprocating gas compressor that prevents the D-ring 107 and the wall surface of the cylinder 101 from sticking to each other and prevents the intake noise from increasing.

[0007]

[Means for Solving the Problems]

 The present invention includes a piston body having a hollow portion which serves as an intake passage and an outer diameter substantially equal to the inner diameter of the cylinder, and a piston crown portion which is connected to the crown portion of the piston body and has an annular ring mounting groove on the outer peripheral portion. A piston having a piston crown portion that extends radially through the peripheral wall of the piston crown portion and has an intake hole that connects the hollow portion of the piston body and the ring mounting groove; and a ring mounted in the ring mounting groove. In a reciprocating gas compressor that includes a rubber elastic seal ring that cooperates with the bottom of the mounting groove to form an intake valve, the piston crown has an outer diameter that is smaller than the outer diameter of the piston body. The outer circumference of the rubber elastic seal ring in the open state has an outer diameter that does not contact the wall surface of the cylinder.

[0008]

[Operation and effect of the device]

 According to the present invention, the rubber elastic seal ring does not come into contact with the wall surface of the cylinder when the intake valve is open, even if the rubber elastic seal ring is softened due to the thermal effect of gas compression. For this reason, when the piston is in the descending stroke, the rubber elastic seal ring in the open state also descends together with the piston, and the effective sectional area of the intake passage formed by this rubber elastic seal ring and the bottom of the ring mounting groove is Compared with the case of the conventional reciprocating gas compressor, it does not become smaller. Therefore, the flow velocity of the air passing through the intake passage does not increase, and high intake noise is prevented.

[0009]

【Example】

 Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIG. A reciprocating air compressor 1 according to an embodiment of the present invention includes a cylinder 2 and a piston 3. Although the discharge reed valve and the discharge chamber block are not shown in FIG. 1, the structure and operation of these discharge reed valve and the discharge chamber block are the same as those of the conventional reciprocating gas compressor.

The outer diameter of the crown portion 4 of the piston 3 is set to be considerably smaller than the outer diameter of the body portion 3 a of the piston 3. A plurality of intake holes 5 are provided so as to radially penetrate the peripheral wall 4a of the crown portion 4 and are scattered in the circumferential direction of the crown portion 4 at regular angular intervals. These intake holes 5 are formed with an annular ring mounting groove 6 at a portion where the intake holes 5 open at the outer peripheral portion of the crown portion 4 of the piston 3. The intake hole 5 connects the hollow portion 10 serving as an intake passage and the ring attachment groove 6. The ring mounting groove 6 has a V-shaped bottom surface, and the D ring 7 is mounted in the ring mounting groove 6. An intake valve 11 is formed by the bottom surfaces of the D ring 7 and the ring mounting groove 6. Since the outer diameter of the D ring 7 is much smaller than the inner diameter of the cylinder 1, the D ring 7 does not come into contact with the wall surface of the cylinder 1 even when it is expanded in the radial direction with the intake valve 11 open. Therefore, the D ring 7 expanded in the radial direction does not stick to the wall surface of the cylinder 1 even if it is softened by being affected by heat. An annular shoulder portion 8 is formed between the crown portion 4 of the piston 3 and the body portion 3a.

The cylinder upper wall 9 forming the crown of the cylinder 2 is also formed as a hollow stepped disc in conformity with the shape of the upper end of the piston 3 including the crown 4 and the shoulder 8. When the piston 3 rises to the top dead center, the crown portion 4 of the piston 3 is inserted into the central convex portion 9a of the cylinder upper wall 9, and the shoulder portion 8 of the piston 3 is the shoulder portion of the cylinder upper wall 9. Ascend to the extent that a slight gap is left on 9b. Thus, there is no dead space between the piston 3 and the cylinder 1 that does not contribute to compression. Therefore, the compression efficiency of the reciprocating gas compressor of the present invention is not lower than that of the conventional reciprocating gas compressor.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a main part of a reciprocating gas compressor according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of a main part of a conventional reciprocating gas compressor.

[Explanation of symbols]

 2 Cylinder 3 Piston 3a Piston main body 4 Piston crown 4a Piston crown peripheral wall 5 Intake hole 6 Ring mounting groove 7 D ring (rubber elastic seal ring) 10 Hollow part 11 Intake valve

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Mitsuyasu Takatsuru 6-6 Hakozakicho, Nihonbashi, Chuo-ku, Tokyo Max Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. A piston body having an outer diameter substantially equal to the inner diameter of a cylinder and having a hollow portion serving as an intake passage, and a piston crown portion connected to a crown portion of the piston body and having an annular ring mounting groove on an outer peripheral portion. And a piston which comprises a piston crown portion which extends radially through the peripheral wall of the piston crown portion and which has a suction hole for connecting the hollow portion of the piston body and the ring mounting groove, and a ring which is mounted in the ring mounting groove. In a reciprocating gas compressor including a rubber elastic seal ring that cooperates with the bottom of the mounting groove to form an intake valve, the piston crown has an outer diameter smaller than the outer diameter of the piston body, and the intake valve is A reciprocating gas compressor, wherein an outer peripheral portion of a rubber elastic seal ring in an opened state has an outer diameter that does not contact a wall surface of a cylinder.