JPS5820976A - Reciprocating compressor - Google Patents

Abstract

PURPOSE:To raise the efficiency of a compressor, by reducing the flow resistance of fluid handled by the compressor by arranging suction ports and exhaust ports on respective circular arrays around a hole into which a valve bolt is inserted, and shaping both of the suction ports and exhaust ports in elongated circular forms. CONSTITUTION:An annular suction groove 19 is formed in the lower surface of a valve plate 13 in the manner of encircling a hole 18 into which a valve bolt 16 is inserted, and a plurality of circular suction ports 12' and suction ports 12 shaped in the form of elongated circles having different lengths are formed in the annular groove 19 irregularly in the circumferential direction. Similarly, an annular exhaust groove 20 is formed also around the hole 18 in the upper surface of the valve plate 3, and a plurality of arcuate exhaust ports 13 are formed in the annular groove 20 equiangularly in the circumferential direction. With such an arrangement, it is enabled to reduce the flow resistance of fluid and to thereby raise the efficiency of compressor.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the structure of a valve plate of a semi-hermetic reciprocating compressor, which is incorporated into a refrigeration cycle, for example, and improves the operating efficiency of the compressor, especially when operating at a low compression ratio. The purpose is to increase energy saving 2 effects.

The present invention will be described below with reference to FIGS. 1 and 2 showing one embodiment thereof.

1 is the upper case of the reciprocating compressor, 2 is the lower case,
The upper case 1 and the lower case 2 are assembled together with a valve plate 3 sandwiched between them. Upper case 1
A suction section 4 and a discharge section 6 are provided on the outside, and the inside of the upper case 1 is divided into a suction chamber 7 and a discharge chamber 8 by a partition wall 6, the suction chamber 7 communicating with the suction section 4, and the discharge chamber 8. is in communication with the discharge section 5. A cylinder cylinder 9 is formed inside the lower case 2, and a reciprocating piston 1o is disposed within the cylinder cylinder 9. 11 is the piston 10
It is a crankshaft that reciprocates. On the valve plate 3,
Suction holes 12 and 1 communicate the suction chamber 7 and the cylinder cylinder 9.
2' and a discharge hole that communicates the discharge chamber 8 and the cylinder cylinder 9 are formed. Further, on both sides of the valve plate 3, there are annular arm-shaped suction valves 14 and 11 for opening and closing suction holes 12 and 12', respectively.
A discharge valve 16 for opening and closing the discharge hole 13 is attached.

That is, the suction valve 14 and the discharge valve 16 are supported at their centers by the valve plate 3 by the valve bolts 16, the suction valve 14 facing the cylinder cylinder 9, and the discharge valve 16 facing the discharge chamber 8. Note that 17 is a discharge valve holder which is also attached with a valve bolt 16.

Here, the shapes and arrangement of the suction holes 12, 12' and the discharge hole 13 are as shown in FIG. That is, regarding the suction holes 12 and 12', an annular suction groove 19 is formed on the lower surface of the valve plate 3 centered on the valve bolt hole 1B through which the valve bolt 16 passes, and an arcuate groove is formed in the annular suction groove 19. Suction holes 12 with different lengths and circular suction holes 1
Multiple 2′.

The discharge holes 13 are arranged irregularly in the circumferential direction, and the discharge holes 13 are formed on the upper surface of the valve plate 3 by the same valve bolts. When the crankshaft 11 rotates and reciprocates the piston 10, gas is sucked from the suction section 4 into the suction chamber 7 during the suction process of the compressor: the suction valve 14 is opened and the gas is sucked from the suction holes 12 and 12'. The suction gas is transferred to the cylinder 9. It leads to a space 21 formed by the piston 1o and the valve plate 3.

Next, during the compression process of the compressor, the gas in the space 21 pushes up the discharge valve 16 through the discharge hole 13, is sent to the discharge chamber 8, and is further sent out from the discharge part 5 to the outside of the compressor. In the above embodiment, the reason why the arc-shaped suction hole 12 and the circular suction hole 12' having different lengths are arranged at irregular center angles with the valve bolt hole 18 as the center is as follows. A part of the annular suction groove 19 on the lower surface of the plate 3 is interfered with by the discharge chamber 8, making it impossible to provide a suction hole in this part. Since a uniform stress is generated, the length of the suction hole 12 should be considered and the arrangement of the suction holes 12 and 12' should be designed and determined in the best possible manner so that this unbalanced response is as small as possible. It's for a reason.

Therefore, only the arc-shaped suction hole 12 may be provided without providing the circular suction hole 12'.

Conventionally, the valve plate of this type of compressor has a structure as shown in FIG. That is, the joint is the valve plate, and the valve bolt hole 18'
An annular discharge groove 20' is provided around the center of the discharge groove 20'.
A plurality of circular discharge holes 13' are formed in the inside, and
A plurality of circular suction holes 12 are formed around the valve bolt hole 18'.
# is formed, and the discharge hole 13' and the suction hole 12'
The number of holes was adjusted depending on the design specifications, and the number of holes was increased to accommodate low compression ratio operation specifications where the specific volume of discharged gas is large. However, in such a conventional valve plate structure, the diameters of the discharge and suction holes are small, so even if the number of holes is increased, the fluid pile resistance per hole is large, which reduces the compressor's insulation efficiency. This did not improve much, and the number of parts to be machined increased in areas that required highly accurate machining, which was not favorable for machining.

On the other hand, as is clear from the above embodiments, in the reciprocating compressor of the present invention, both the suction hole and the discharge hole have a long arc shape with the valve bolt hole at the center. Since the opening area of a single hole becomes large, gas with a large specific volume flows during low compression ratio operation (especially at the discharge hole).
, the fluid resistance is reduced, the loss factor that reduces the compressor's adiabatic efficiency caused by fluid resistance is reduced, the efficiency of the compressor is increased, and the energy saving effect is increased. The number of suction holes, discharge holes, and outlet holes is significantly reduced, which reduces the number of machining points, and the arc-shaped suction and discharge holes can be easily machined using the valve bolt hole as the machining reference hole, which increases the machining cost. can be suppressed. Note that according to the present invention, the efficiency of the compressor is improved not only at low compression ratios but also at high compression ratios.

[Brief explanation of the drawing]

Fig. 1 is a partially sectional side view of a reciprocating compressor showing an embodiment of the present invention, and Fig. 2 is a side view taken along line u-n' in Fig. 1 with the discharge valve and suction valve removed. FIG. 3 is a sectional view of the main part, and FIG. 3 is a plan view of the main part of the valve plate of a conventional compressor. 3... Valve plate, "9... Cylinder cylinder,
1゜...Piston, 12...Suction inlet hole, 13...i...Water hole, 14...Suction valve,
16. Mountain...Discharge valve, 16...Valve bolt, 18
...... Valve bolt hole, 19... Annular suction groove, 2o... Annular discharge groove. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 3'

Claims (1)

[Claims] A valve plate is attached to one end of the cylinder cylinder in which the reciprocating piston is housed, and an annular suction groove centered on the valve bolt hole is formed on one surface of the valve plate on the cylinder cylinder side. A plurality of suction holes having arcuate shapes and different lengths are arranged irregularly in the circumferential direction, and an annular discharge groove centered on the valve bolt hole is formed on the other surface of the valve plate. ,
A plurality of arc-shaped discharge holes are regularly arranged in the circumferential direction within the annular discharge groove, and a suction valve and a discharge valve for opening and closing the suction hole and the discharge hole, respectively, are passed through the valve bolt hole. A reciprocating compressor attached to the valve plate with valve bolts.