JPS587835B2 - compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a compressor, and more particularly to a compressor structure that achieves a noise reduction effect by alleviating pulsation of discharged fluid (discharged gas).

In a cooling compressor that compresses a refrigerant such as Freon gas, a plate-shaped side plate and a side cover covering the outside thereof are fixed to the end face of a cylinder block containing a built-in piston-cylinder mechanism, and the side cover is attached to the side plate. A structure is adopted in which a low-pressure side through hole is provided for flowing into the cylinder, and a high-pressure side through hole is provided for flowing out from the cylinder.

Conventionally, as a noise reduction mechanism for this type of compressor,
As shown in No. 44313 or Japanese Unexamined Patent Publication No. 54-31611, a flat discharge chamber is separately formed on the outer wall side of the side cover that forms the high and low pressure chambers, and the high pressure chamber is connected to the discharge outlet via this discharge chamber. It is known to muffle the sound from the discharged refrigerant by guiding the discharged refrigerant to the refrigerant.

However, with this silencing mechanism, the silencing effect is achieved simply by smoothing the pulsating energy due to the volume expansion and pressure drop when the refrigerant is discharged from the high-pressure chamber to the discharge chamber through a small hole with a throttling function. Because the sound was leaning, a sufficient sound deadening effect could not be obtained.

The present invention discharges refrigerant from a high-pressure chamber toward approximately the center of the discharge chamber, and by configuring the refrigerant to be guided from approximately the center of the discharge chamber to the discharge port, the radial direction of the discharged refrigerant discharged into the discharge chamber is improved. The aim is to achieve a greater noise reduction effect in a flatter, smaller volume discharge chamber by effectively dispersing the air into the air.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, the cylinder block has left and right parts 12,1
It is divided into two parts, which are joined together at a central mating surface.

A swash plate chamber 14 is formed in the center of the cylinder block, and cylinders 16, 16 are arranged parallel to the central axis on both the left and right sides.
is formed.

A plurality of cylinders (for example, three on each side, six in total) are formed in the circumferential direction.

At the center of the cylinder block is a shaft 1 that passes through it.
8 is supported, and a swash plate 20 is fixed to a portion of the shaft corresponding to the swash plate chamber 14.

A double-acting piston 22, 22 is fitted into each cylinder 16, 16, which is arranged parallel to and around the shaft 18.

Each piston has slippers 24 fixed on both sides of the swash plate.
and is connected to the swash plate 20 via steel balls 26 supported by each slipper.

The shaft 18 is rotatably supported in the cylinder block 12.12 by radial bearings 28, 28,
Further, thrust bearings 30, 30 are provided to receive the axial component force of the swash plate 20.

Valve plates 32, 3 are provided on both end surfaces of the cylinder blocks 12, 12.
2 and side plates 34 are mounted on top of each other, and a front side cover (left side in the figure) 36 and a rear side cover (right side in the figure) 38 are attached to the outside of each side plate.

A cylindrical housing 40 is provided around the cylinder blocks 12, 12.

In the illustrated example, the left end of the cylindrical housing 40 is engaged with the stepped portion of the front side cover 36, and the right end of the cylindrical housing is fastened to the rear side cover 38 with screws or the like, so that each valve The plates 32, 32, each side plate 34, 34, the front side cover 36, and the rear side cover 38 are connected to the cylinder block 12.12.
It is designed to be fixed against.

A fluid suction port 42 for refrigerant gas (Freon gas) is provided approximately at the center of the housing 40, and opens into the swash plate chamber 14 through a through hole 44 formed in the cylinder block.

A shaft seal 46 is attached to the center opening of the front side cover 36 to seal between the shaft 18 and the front side cover 36.

Through holes 48, 48 are formed before and after the swash plate chamber 14,
The through hole communicates with enlarged passages 50, 50 formed at the front and rear of the cylinder block.

The front and rear enlarged passages communicate with the front and rear low pressure chambers 54, 54 through low pressure side passage holes 52, 52 formed in the front and rear side plates 34, 34, respectively.

Each low pressure chamber 54, 54 is defined by each front side cover and rear side cover 36, 38.

In addition, each low pressure chamber 54.54 is connected to each side plate 34.3.
It communicates into each cylinder 16, 16 through another low pressure side passage hole 56, 56 formed in 4.

These low-pressure side passage holes 56, 56 communicate with the cylinder 16.16 and the low-pressure chamber 54.54 during the suction stroke of each piston 22 by an inlet valve (not shown) formed in each valve plate 32, 32. It has become.

Furthermore, high pressure chambers 60, 60 are defined around each low pressure chamber 54, 54 by respective side covers 36, 38.

Each high pressure chamber communicates into each cylinder 16, 16 via a high pressure side through hole 58, 58 formed in each side plate 34, 34.

Each high pressure side through hole 58.58 is connected to each side plate 34,3.
4 provides communication between the cylinders 16, 16 and the high pressure chamber 60 during the discharge stroke of each piston 22.

The rear side cover 38 is approximately bowl-shaped,
The inside thereof is an annular partition wall portion 38B (shown in FIGS. 6 and 7).
Two chambers are defined inside and outside in the radial direction.

The radially inner chamber is the low pressure chamber 54 and the radially outer chamber is the high pressure chamber 60.

The inside of these chambers (left side in the drawing) is the side plate 34.
partitioned by.

A substantially dish-shaped discharge chamber cover 72 is fixed to the outside of the rear side cover 38 (on the right side in the drawing), and a discharge chamber 68 is defined between the rear side cover and the discharge chamber cover. .

The high pressure chamber 60 and the discharge chamber 68 are communicated with each other through a plurality of small holes 70 (for example, four formed at equal intervals in the circumferential direction) formed in the side cover 38.

Each small hole 70 is formed in a direction that substantially coincides with an extension of the central axis of the cylinder blocks 12, 12.

In the illustrated example, each small hole 70 is formed at an angle with respect to the central axis of the cylinder block and extends along the central axis.

In this way, the high pressure chamber 60 and the discharge chamber 68 are communicated with each other through a small hole 70 extending toward approximately the center of the discharge chamber.

At a substantially central position of the discharge chamber 68, that is, a substantially central position of the discharge chamber cover 72, a refrigerant outlet 64 for discharging compressed refrigerant gas is provided approximately at the center of the discharge chamber cover 72. is located directly on the

The operation of the compressor shown in FIG. 1 described above is as follows.

Low-pressure refrigerant gas introduced from the suction port 42 enters the swash plate chamber 14 within the cylinder block.

Since the refrigerant has a low temperature and contains lubricating oil, it cools and lubricates the swash plate 20, thrust bearings 30, 30, etc. by direct contact.

The refrigerant flows as shown by the arrow in FIG.
through which it enters each enlarged passageway 50,50.

At this time, the refrigerant suddenly slows down and only the oil falls downward, passing through the oil return hole (not shown) to each radial bearing 28,
Lubricate 28.

Furthermore, the refrigerant gas is introduced into each of the low pressure chambers 54, 54 through the low pressure side through holes 52, 52.

The refrigerant introduced into the front low pressure chamber cools and lubricates the shaft seal 46 provided therein.

Then, during the suction stroke of each piston, the refrigerant flows through the low pressure side through holes 56, 56 formed in each side plate 34, 34.
The air is drawn into each cylinder 16, 16 through.

When the piston 22 enters the compression stroke (discharge stroke), the refrigerant in each cylinder flows through the high pressure chamber through hole 58 of the side plate 34.
It is discharged into the high pressure chamber 60 in a high pressure state (compressed state) through the discharge valve action.

The front-side and rear-side high-pressure chambers 60, 60 are communicated with each other through a pipe (not shown) or the like, so that the high-pressure refrigerant in the front-side high-pressure chamber also flows into the rear-side high-pressure chamber.

The high-pressure refrigerant introduced into the high-pressure chamber 60 on the rear side flows into the discharge chamber 68 through a plurality of small holes 70 formed in the side cover 38, and then flows into the discharge chamber 68 through the discharge port 64 provided in the center of the discharge chamber.
It is discharged from the refrigeration cycle through piping, etc.

However, the refrigerant discharged into the high pressure chamber 60 has a pressure pulsating component, and if it is discharged from the discharge port 64 into the refrigeration cycle in this state, the piping and condenser will be vibrated and the refrigerant will be transmitted through the vehicle body. Vibration and noise are generated in the vehicle interior, but in the above-described embodiment, the high-pressure refrigerant in the high-pressure chamber 60 diffuses and expands when it flows into the discharge chamber 68 through the small hole 70. The high frequency components of the discharge pressure pulsations discharged through the small holes 70 formed toward each other are effectively attenuated by mutual interference when they collide at the central portion.

Therefore, the expansion and interference effects can effectively muffle the sound.

The sound deadening effect due to the expansion can be achieved by appropriately selecting the ratio of the total cross-sectional area of each small hole 70 to the area of the discharge chamber 68, that is, the opening ratio.

FIG. 2 is an explanatory diagram showing a model of the aperture ratio, and the diameter A
When entering a silencer with a larger diameter B from the suction pipe (corresponding to the small hole 70), the opening ratio is πB
It is expressed by 2/πA2.

Further, by appropriately selecting the thickness d of the silencer, further silencing effects can be achieved.

C in FIG. 2 indicates the diameter of the discharge port (corresponding to the discharge port 64 in FIG. 1) from the silencer.

Note that the cross-sectional area of each small hole 70 must be selected to be at least a certain minimum value, since if it is made too small, pressure loss will occur and performance will deteriorate.

Further, the cross section of each small hole 70 may be formed into an appropriate shape such as a rectangular shape in addition to a circular hole.

In addition, in order to cause interference of the high frequency components of the discharge pressure pulsation and utilize this to enhance the silencing effect, the discharge port with diameter C should be provided near the center of the silencer with diameter B, as shown in Fig. 2. is the most effective.

In the embodiment shown in FIG. 1, this concept is applied, and the discharge port 64
is provided approximately at the center of the discharge chamber 68.

FIG. 3 is a chart illustrating the distribution of pulsating pressure P (kg/cm2) with respect to discharge pressure pulsating frequency F (Hz).

The dotted line X in Fig. 3 exemplifies the distribution state of discharge pressure pulsation according to the prior art, and the noise range indicated by diagonal lines in the figure, that is, the component whose frequency is higher than Po and whose pulsation pressure is higher than Po, accounts for a fairly large proportion. It includes.

For this reason, conventional compressors have large vibrations and noise that cause discomfort.

On the other hand, the solid line Y in FIG. 3 illustrates the distribution of discharge pressure pulsations of the compressor according to the present invention.

As is clear from this, according to the present invention, all high frequency component pressures higher than frequency Fo can be attenuated to lower than Po, and all components in the noise range (shaded range) can be eliminated.

Therefore, in the compressor according to the present invention, vibrations and noise can be suppressed to the extent that they are hardly felt.

Furthermore, in the embodiment shown in FIG. 1, the rear side force bar 38 is used to provide a low pressure chamber 54 and a high pressure chamber 6 inside thereof.
0, and a discharge chamber 68 is provided on the outside thereof.

When the compressor is in operation, the pressure in the low pressure chamber is low, and the pressure in the high pressure chamber and discharge chamber is high. Also, due to the pressure loss when passing through the small hole 70, the pressure in the discharge chamber is lower than the average pressure in the high pressure chamber. Although it is slightly lower, the difference is small.

Therefore, a force approximately equal to the value obtained by multiplying the pressure difference between the discharge chamber (high pressure) and the low pressure chamber (low pressure) by the facing area of the low pressure chamber is applied to the disk portion 38A of the side force bar 38 against the cylinder. It acts in the direction (towards the left in Figure 1).

Therefore, the annular partition wall 38B of the side cover 38 is strongly pressed against the surface of the side plate 34 (actually, packing etc. are interposed), and the airtightness between the low pressure chamber 54 and the high pressure chamber 60 is reliably maintained. It also has the effect of

FIG. 4 is a partial view of a second embodiment of the compressor of the present invention.

In this embodiment, a partition plate γ6 having a through hole 74 approximately in the center is interposed between the side force bar 38 and the discharge chamber cover 72, and the discharge chamber 68 of the embodiment of FIG. This embodiment differs from the embodiment shown in FIG. 1 in that it is divided into two chambers, a discharge chamber 68B, and the structure of other parts is substantially the same.

Therefore, reference numbers in FIG. 4 that are the same as those in FIG. 1 indicate corresponding or identical parts, respectively.

The through hole 74 has a function of discharging high-pressure refrigerant toward the center of the discharge chamber 68B.

According to the structure shown in FIG. 4, the high-pressure refrigerant in the high-pressure chamber 60 flows through the small hole 70 → second high-pressure chamber 68A → through hole 74 → discharge chamber 68B →
While passing through the discharge port 64, rapid expansion and contraction are repeated, thereby further enhancing the sound deadening effect.

FIG. 5 is a partial view of a third embodiment of the compressor of the present invention.

In this embodiment, a refrigerant outlet 78 is formed in the center of the discharge chamber cover 72, a radial passage 80 is formed continuous with the outlet, and a discharge outlet 6 is formed at the outlet end of the radial passage.
This embodiment differs from the embodiment shown in FIG. 1 in that the number 4 is provided, and the other structures are substantially the same.

Therefore, parts that are the same as or correspond to parts in FIG. 1 are designated by the same reference numerals.

According to the structure shown in FIG. 5, in addition to the effect of the embodiment shown in FIG. 1, the axial length of the compressor can be minimized.

In compressors used in automobile air conditioners, etc., installation space is limited, and in many cases it is not possible to provide the discharge port 64 and the piping connected thereto in the axial direction.
The illustrated embodiment solves this problem and is convenient.

In each of the embodiments shown in FIG. 5, the high-pressure refrigerant flowing through the high-pressure chamber 60 → small hole 70 → discharge chamber 68 → discharge port 64 expands and interferes in the same state as in the case of FIG. , so a similar sound deadening effect can be achieved.

Note that the shapes of the low pressure chamber 54 and the high pressure chamber 60 in each of the embodiments described above are, of course, concentric circular and annular chambers with a completely closed annular partition 38B as shown in FIG. , as shown in FIG. 7, a part of the annular partition wall 38B is formed into a substantially U-shape connected to the outer circumferential wall of the side cover;
It is also possible to adopt a structure in which a U-shaped low pressure chamber 54 is defined in the same part, and a high pressure chamber 60 is defined between the outside thereof and the outer circumferential wall of the side cover.

Regardless of the shape, a similar sound deadening effect can be achieved.

As is clear from the above description, according to the present invention, high-pressure refrigerant is discharged from the high-pressure chamber toward the center of the flat discharge chamber provided adjacent to the outside of the low- and high-pressure chambers, and approximately at the center of the discharge chamber. Since the high-pressure refrigerant is guided to the discharge port from the outlet provided in the discharge chamber, in addition to the silencing effect due to the expansion in the discharge chamber, the silencing effect due to interference caused by the effective diffusion of the refrigerant can be expected, resulting in a smaller volume. We were able to achieve more effective noise reduction in the discharge chamber.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a first embodiment of a compressor according to the present invention;
Fig. 2 is an explanatory diagram showing a principle model of the aperture ratio of an inflatable silencer, Fig. 3 is a chart illustrating the frequency distribution of discharge pulsating pressure of a conventional compressor and a compressor according to the present invention, and Fig. 4 is a diagram of the present invention. A partial vertical sectional view showing the main parts of a second embodiment of the compressor of the invention,
FIG. 5 is a partial vertical sectional view showing the main parts of a third embodiment of the compressor of the present invention, and FIGS. 6 and 7 are examples of the shapes of the low discharge chamber and high pressure chamber of the compressor of the present invention. and FIG. 7 is a cross-sectional view showing another example. 12...Cylinder block, 16...
Cylinder, 18...Shaft, 22...
Piston, 32... Valve plate, 34... Side plate 36... Front side cover, 38... Rear side cover, 42...
...Intake port, 54...Low pressure chamber, 56...
・Low pressure side hole, 58...High pressure side hole, 60...
...High pressure chamber, 64...Discharge port, 68...
...Discharge chamber, 68A...Second high pressure chamber, 68B
...Discharge chamber, 70...Small hole, 72...
...Discharge chamber cover, 74...Through hole.

Claims (1)

[Claims] 1. A plate-shaped side plate is brought into contact with the end face of the cylinder block, and low and high pressure chambers communicating with the cylinder are defined on the outer side of the side plate through the side plate, and a flat side plate is formed on the side opposite to the side plate of the low and high pressure chambers. A discharge chamber is defined adjacently to the discharge chamber, and a through hole is provided to communicate the high pressure chamber and the discharge chamber, and the high pressure refrigerant is discharged from the high pressure chamber to the discharge chamber and from an outlet provided in the discharge chamber. In a compressor configured to lead high-pressure refrigerant to a discharge port of the compressor, the through hole is opened toward approximately the center of the discharge chamber, and the high-pressure refrigerant outlet provided in the discharge chamber is opened toward the center of the discharge chamber. A compressor characterized by having an opening approximately in the center.