JPS59218393A - Compressor - Google Patents

Abstract

PURPOSE:To aim at reducing overcompression upon a discharge stroke and as well at reducing loss loss due to re-expansion of coolant gas for a low pressure vane chamber, by providing a plurality of holes in two rows, discharge valves closely contacted separately to the discharge holes and having different distances from their supporting sections, and discharge plate retaining plates. CONSTITUTION:In the positions of discharge holes 25a, 25b in a first row, the gap between a cylinder 19 and a rotor 21 is large, and therefore a large effective area may be obtained although the number of the discharge holes is small. Therefore, overcompression may be reduced, and as well the amount of re-expansion of coolant gas for a low pressure vane chamber, which occurs when a vane 23 passes by the discharge holes, may be also reduced. When coolant gas is sufficiently discharged, since discharge valves 27a, 27b are independently operated in their parts which are branched from their supporting sections. Only long parts of discharge holes 26a, 26b in a second row are opened while the short parts of the discharge holes 25a, 25b are maintained to be closely contacted to the valves. Accordingly, the re-expansion of coolant gas for the low pressure vane chamber is reduced. With this arrangement, loss during the discharge stroke can be reduced to make it possible to enhance the efficiency of the compressor.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a sliding vane rotary compressor for car air conditioners.

Structure of a conventional example and its problems As shown in FIG. 1, a conventional compressor has a cylinder 1 having a cylindrical space inside, and a blade chamber 2a fixed to both sides of the cylinder 1, which is an internal space of the cylinder 1.

2b on both sides thereof (not shown in FIG. 1), a rotor 3 disposed at the center of the cylinder 1, and a rotor 3 slidably engaged in a groove 4 provided in the rotor 3. It is composed of a plurality of vanes 6. As the rotor 3 rotates, the vanes 6 are projected outward by centrifugal force, and their tip surfaces slide on the inner wall surface of the cylinder 1 to prevent leakage of compressed refrigerant gas. Further, the cylinder 1 is formed with suction holes ea and eb for supplying refrigerant gas to the blade chambers 2a and 2b, and discharge holes 7a and 7b which are passages for discharging compressed refrigerant gas to the outside of the blade chamber. Note that 8a and sb are discharge valves, and 9a.

9b is a discharge valve holding plate. 3. FIG. 2 is a side sectional view of the same compressor, 10 is a front plate which is a side plate, 11 is a rear plate, 12 is a front case, 13 is a rotating shaft, 14 is a shell container, and 15 is provided in the front case 12. 16 is a discharge port provided in the shell container, 17 is an oil separator, and 18 is a clutch.

In a compressor in which the inner surface of the cylinder 1 is approximately elliptical as shown in FIG. 1, the air is supplied to the blade chambers 2a, 2b from the suction holes 6a, 6b through the flow path of the suction port 15 or 1. Then, as the rotor 3 rotates, the vanes 5 slide on the inner wall surface of the cylinder 1, and the refrigerant gas is compressed, and when the pressure inside the blade chamber becomes higher than the discharge pressure,
The discharge valves 9a and 9b open, and the discharge is discharged from the discharge holes 7a and 7b into a common space inside the shell container 14, and then sent out from the discharge port 16 to the outside.

FIG. 3 shows the shape of a discharge valve used in a conventional compressor. As shown in Fig. 1, the discharge hole is located near the end point of the blade chamber, which is the closest point between the rotor and the inner wall of the cylinder.
A plurality of small holes are drilled in a line, and the discharge valve is a flat plate valve with a shape that branches out from the support portion into a plurality of equal lengths so that each small hole is brought into close contact with each other.

By the way, the position, shape, and number of the discharge holes are determined by the amount of refrigerant gas to be discharged. In other words, the discharge hole must have a flow path large enough to discharge a sufficient amount of refrigerant gas drawn into the vane chamber, and the refrigerant gas remaining in the blade chamber after the vane passes through the discharge hole must be recirculated. Compression must be minimized. Therefore, a discharge hole having a shape as large as possible is provided at a position closest to the rotor and the inner wall of the cylinder.

However, in such a configuration, the gap between the rotor and the inner wall of the cylinder where the discharge holes are provided is narrow, making it impossible to obtain a flow path sufficient to discharge refrigerant gas, resulting in overcompression that is considerably greater than the discharge pressure. This will increase losses. Therefore, it is necessary to increase the diameter of the discharge hole or increase the number of holes to make the flow path thicker, but in this case, re-expansion of refrigerant gas into the low-pressure side blade chamber occurs when the vane passes through the discharge hole. This will result in increased losses. In addition, if the discharge hole is formed at a position with a wide gap between the rotor and the cylinder inner wall to reduce loss due to re-expansion, the flow path will be sufficiently large, but the amount of residual refrigerant gas in the blade chamber after the vane passes through the discharge hole will increase. However, the loss due to recompression will increase. The above-mentioned problem is particularly noticeable in a compressor in which the inner surface of the cylinder is approximately elliptical because the gap between the rotor and the inner wall of the cylinder becomes considerably narrower at the discharge portion.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks and provides a highly efficient compressor with less loss during the discharge stroke.

Structure of the Invention The present invention provides a rotor provided with a groove in which a vane can slide, a slidable vane housed in the rotor, a cylinder housing the rotor therein, and a rotor provided on both sides of the cylinder. Fixed said vane.

a side plate that seals the space of the blade chamber formed by the rotor and the cylinder on its side surface; a suction hole for supplying refrigerant gas into the blade chamber; a plurality of discharge holes arranged in two rows; It is made up of a discharge valve of different lengths and a discharge valve holding plate that are in close contact with the support and are branched from the support part, and has the unique effect of reducing loss during the discharge stroke.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 4 to 6. In the figure, 19 is a cylinder, 20a, 2
0b is a blade chamber which is a space inside the cylinder 19, 21 is a rotor, 22 is a vane groove provided in the rotor 21, 23 is a vane, 24a and 24b are suction holes, and the above is the same structure as the conventional example. It is. The difference from the conventional configuration is that the discharge holes are arranged in two rows, and the ones with larger diameters 25a and -26b are positioned at positions where the gap between the cylinder 19 and the rotor 21 becomes larger.
Discharge valves 27a and 27b are provided with holes 26a and 26b having small diameters at positions closest to the cylinder 19 and the rotor 21, and corresponding to the two types of discharge holes.

The point is that the lengths of the portions branching from the support portion are made different so that the discharge valve holding plates 2sa and 2sb are brought into close contact with each discharge hole separately.

In the compressor configured as above, the gap between the cylinder 19 and the rotor 21 is large at the positions of the discharge holes 25a and 25b in the negative row, and the number of discharge holes is small, resulting in a large effective area. As well as reducing overcompression,
It is also possible to reduce the amount of re-expansion of refrigerant gas into the low-pressure side blade chamber that occurs when the bay 723 passes through the discharge holes 25a, 26b. On the other hand, the second row of discharge holes 26a, 26
b is provided to discharge the refrigerant gas remaining in the blade chamber after the vane 23 passes through the first row of discharge holes 25a and 25b, and since the amount of residual refrigerant gas is small,
Even if the hole diameter is made smaller and the number of holes is reduced, the refrigerant gas can be sufficiently discharged. At this time, the parts of the discharge valves 27a and 27b branched from the support part operate independently.
Only the long parts of the second row of discharge holes 26a and 26b were open, and the short parts of the - row of discharge holes 26a and 26b were in close contact! , so re-expansion of the refrigerant gas into the low-pressure side vane chamber occurs when the vane 23 passes through the discharge holes 26a, 26b in the second row, but the amount is extremely small.

As described above, according to this embodiment, the discharge holes are arranged in two rows, and -
The second row of discharge holes is located away from the closest part of the cylinder and rotor so that the cross-sectional area of the discharge holes, which is determined by the hole diameter and number of holes, is small. By making the hole diameter small and the number of holes close to each other, and configuring the shape of the discharge valve corresponding to the discharge hole so that the length of the part branching from the support part is different, overcompression and low pressure side during the discharge stroke can be avoided. The amount of re-expansion of refrigerant gas into the blade chamber can be reduced, and as a result, loss in the discharge stroke can be reduced.

Although this embodiment describes a compressor having two blade chambers, similar effects can be obtained in a compressor having one, three or more blade chambers.

Effects of the Invention As described above, the present invention comprises a plurality of discharge holes arranged in at least two rows, a discharge valve having different lengths branched from a support portion, and a discharge valve holding plate, each of which is in close contact with the discharge holes separately. C makes it possible to reduce losses due to overcompression in the discharge stroke and the amount of re-expansion of the refrigerant gas into the low-pressure side blade chamber, and has the effect of providing a highly efficient compressor.

[Brief explanation of the drawing]

Fig. 1 is a front sectional view of a cylinder of a conventional compressor, Fig. 2 is a side sectional view of the same compressor, Fig. 3 is a plan view of the compressor discharge section, and Fig. 4 is an embodiment of the present invention. FIG. 6 is a front sectional view of the cylinder of the compressor, and FIG. 6 is a plan view of the discharge part of the compressor. 19...Cylinder, 20a, 20b...
・Blade chamber, 21... Rotor, 23...
Vanes, 25a, 26b... - row of discharge holes,
26a, 2eb... Second row discharge hole, 27
a, 27b...Discharge valve, 28a. 28b...Discharge valve holding plate. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3 Figure 4 Figure 5

Claims (1)

[Scope of Claims] A rotor provided with a groove in which the vane can slide, a slidable vane housed within the rotor, a cylinder housing the rotor therein, and a cylinder fixed to both sides of the cylinder. and the vane and the rotor. a side plate that seals the space of the blade chamber formed by the cylinder on its side surface; a plurality of discharge holes formed in the cylinder and formed in at least two rows in the direction of rotation of the suction hole and the vane; A compressor consisting of discharge valves of different lengths and discharge valve holding plates.