JPS60259775A - Swash plate type compressor - Google Patents

Abstract

PURPOSE:To restrain lubricating oil from flowing into a low-pressure chamber to the utmost as well as to improve the relationship between an oil circulating rate of a refrigerating cycle and a refrigerant flow rate, by installing a low-pressure passage, ranging from a swash plate chamber to the low-pressure chamber, in and around a compressor rotary shaft. CONSTITUTION:A swash plate chamber 7 and each of low-ressure chambers 18 and 18' are partitioned off by a partition walls 17 and 17'. Inside this swash plate chamber, lubricating oil is separated from a suction refrigerant by rotation of a swash plate 2. This separated lubricating oil is the higher in a distribution rate the nearer to the circumferential side of the inside of the swash plate chamber 7. Therefore, each of low-pressure flow passages 19 and 19' is installed in these partition walls 17 and 17' in and around a compressor rotary shaft 3 being low in this distribution rate.

Description

[Detailed description of the invention] [Field of application of the invention] The present invention is used for automobile air conditioners, etc. (1) This relates to a swash plate compressor.

[Background of the invention]

A so-called spray lubrication method is adopted in which lubricating oil is mixed into the refrigerant circulating in the refrigeration cycle, and the refrigerant containing the lubricating oil is guided into the swash plate chamber and sprayed directly onto the swash plate and other sliding parts of the compressor. In a swash plate compressor, the lubricating oil is deposited directly where the compressor sliding parts are once cooled with low-temperature refrigerant, so the lubrication effect is high and the advantage is that the amount of lubricating oil used is small. .

FIG. 1 shows the internal structure of a swash plate compressor that has been put into practical use in the past.

In FIG. 1, 1 and 1' indicate cylinder blocks facing each other with a swash plate 2 in between.
1', a compressor rotating shaft 3 is supported via bearings 4, 4', and the rotating shaft 3 is attached to the swash plate 2. The rotation of the rotating shaft 3 is transmitted to a piston (none of which is shown) via the swash plate 2 and conventionally known steel balls and sliders, and is converted into reciprocating motion of the piston. The refrigerant gas mixed with (2) lubricating oil is drawn into the swash plate chamber 7 formed by the casing 6 and the cylinder block 1.1' through the low-pressure refrigerant suction port 5. The refrigerant gas sucked into the swash plate chamber 7 cools the compressor sliding parts represented by the swash plate 2, and at the same time, the compressor sliding parts are lubricated by the lubricating oil mixed in the refrigerant gas. . Then, the refrigerant gas in the swash plate chamber 7 passes from above the partition walls 8, 8' through the low pressure passages 10, 10' of the other partition walls 9, 9', and enters the low pressure chamber 7.
1.11', and then guided to the next low pressure chamber 14.14' through the low pressure passage 13.13' of the other partition wall 12.12', and then fed into a cylinder (not shown).

In the figure, 15 and 15' are respectively cylinder blocks 1.
The oil tank installed at 1' is shown.

The internal structure of the swash plate type compressor that has been used in practical use is as described above, but in the conventional compressor of this type shown in FIG. It has been found that the following problems arise because the refrigerant gas after cooling and lubricating the parts passes above the partition walls 8, 8' and is guided to the low pressure chamber 11°11' side.

That is, a 114-built swash plate compressor in which lubricating oil is mixed into the refrigerant circulating in the refrigeration cycle, and the refrigerant containing the lubricating oil is guided to the swash plate chamber 7 and directly blown onto the sliding parts of the compressor. In this case, the rotation of the swash plate 2 causes the inside of the swash plate chamber 7 to function as a highly efficient oil separator. In other words, the oil separated from the refrigerant gas by the rotation of the swash plate 2 in the swash plate chamber 7 tends to be blown away toward the outer periphery of the swash plate chamber 7, so the oil distribution in the swash plate chamber 7 is In this state, the oil content ratio is low on the side closer to the compressor rotating shaft 3, and the oil content ratio increases as the distance from the rotating shaft 3 increases.

Therefore, as shown in FIG.
In a swash plate compressor having a structure in which the refrigerant gas after cooling and lubricating the swash plate chamber 7, which has a high oil content, passes above the partition walls 8, 8' and is guided to the low pressure chamber 11, 11' side. Since the refrigerant gas is sent from the outer periphery of the swash plate chamber 7 to the low pressure chamber 11.
As a result of being sent to the 1' side, the oil circulation rate and the refrigerating capacity are correlated, so that as the oil circulation rate increases, the refrigerating capacity decreases.

In consideration of the above, the present applicant has previously proposed
As No. 312, we proposed a swash plate compressor with the structure shown in Figure 2.

In FIG. 2, the same symbols as in FIG. 1 indicate the same parts,
In JP-A No. 52-36312, a filter 16.16' made of glass wool or the like is installed in the middle of the refrigerant passage,
A technique for separating oil in refrigerant gas using the filter 16, 16' is disclosed.

However, there is a filter 16.16 in the middle of the refrigerant passage.
In a structure in which the oil in the refrigerant gas is separated by the filter 16.16', the filter 16.
If an attempt is made to increase the oil separation efficiency by 16', the refrigerant passage resistance tends to increase and the volumetric efficiency tends to decrease. Also, contrary to the above, as a filter 16.16',
If a filter that does not impair volumetric efficiency is used, a sufficient oil separation effect cannot be achieved. therefore,
In a swash plate compressor having a structure in which a filter 16, 16' is provided in the middle of a refrigerant passage, it is desired to develop a filter that can fully satisfy the above two points.

[Purpose of the invention]

The present invention has been made as a result of various research and development in order to solve the above-mentioned problems of the prior art, and its purpose is to:
The oil in the swash plate chamber can be prevented as much as possible from flowing into the low pressure chamber side connected to the swash plate chamber, and eventually into the refrigeration cycle.
The object of the present invention is to provide a swash plate compressor with excellent refrigerating capacity that can reduce the oil circulation rate of the refrigeration cycle and improve the relationship between the oil circulation rate and the refrigerant flow rate of the refrigeration cycle compared to the conventional one. .

[Summary of the invention]

In order to achieve the above object, the present invention has a structure in which lubricating oil is mixed into the refrigerant circulating in the refrigeration cycle, and the refrigerant containing the lubricating oil is guided into the swash plate chamber and can be blown directly onto the sliding parts of the compressor. The swash plate compressor is characterized in that a low pressure passage connecting the swash plate chamber to the low pressure chamber is located near the compressor rotating shaft and penetrates a partition wall that partitions the swash plate chamber and the low pressure chamber. It is something.

[Embodiments of the invention]

Hereinafter, the present invention will be explained based on Figures 1 to 7 (not Figure 3). Figure 3 is a longitudinal sectional view of the internal structure of an embodiment of the swash plate compressor according to the present invention, and Figure 4 is This is a Z arrow view in Figure 3, and in Figures 3 and 4, Figures 1 and 2 are
The same reference numerals as in the drawings indicate the same parts, and 17 and 17' indicate partition walls that partition the swash plate chamber 7 and the low pressure chamber 18.18'. A continuous low-pressure passage 19.19' is located near the compressor rotating shaft 3 and is provided through the partition wall 17.17'.

In the above configuration, refrigerant gas mixed with lubricating oil is sucked into the swash plate chamber 7 formed by the casing 6 and the cylinder blocks 1 and 1' through the low-pressure refrigerant suction port 5. The refrigerant gas sucked into the swash plate chamber 7 cools the compressor sliding parts represented by the swash plate 2, and at the same time, the compressor sliding parts are lubricated by the lubricating oil mixed in the refrigerant gas. Ru. After that, the refrigerant gas in the swash plate chamber 7 is
The low pressure chamber 1 passes through the low pressure passage 19.19' of the partition wall 17.17' with a low oil content located near the compressor rotating shaft 3.
It reaches 8.18'. In the illustrated embodiment, the refrigerant gas guided to the low pressure chamber 18, 18' changes its direction approximately 90 degrees within the detour (low pressure chamber 18, 18') formed by the partition walls 9, 9'. While flowing, the oil is further separated, and the oil separated at the core is supplied to the compressor rotating shaft 3 via oil reservoirs 15, 15'. Also, in the illustrated embodiment, low pressure passages 19, 19 leading from the swash plate chamber 7 to the low pressure chambers 18, 18'
As shown in FIG. 5(a), the wall thickness around the swivel is thicker than that of the partition walls 17, 17' of the swivel. Therefore, even if the oil splashed onto the partition walls 17, 17' flows down along the surfaces of the partition walls 17, 17' due to the lubricating oil spraying action of the swash plate 2, the falling oil will not flow. , because it flows downward along the periphery of the low pressure passage 19, 19', the flowing oil flows into the low pressure chamber 1 along with the refrigerant R.
8.18' can be effectively prevented. On the other hand, as shown in FIG. 5(b), the wall thickness around the low pressure passage 19.19' leading from the swash plate chamber 7 to the low pressure chamber 18°18' is the wall thickness of the partition wall 17.17' around it. If it is the same as that of the partition wall 17.17', the oil splashed onto the partition wall 17.
17', a part of the spilled oil flows into the low pressure chamber 18 and 18' together with the refrigerant R, but as mentioned above, it flows down on the side near the compressor rotating shaft 3. Since the oil content ratio is low, the influence of part of the flowing oil flowing into the low pressure chamber 18, 18' can be almost ignored when actually operating the compressor of the present invention.

FIG. 6 is a refrigerant flow rate-oil circulation rate characteristic diagram of the conventional compressor shown in FIG. 1 and the compressor of the present invention.

(9) As shown in Fig. 6, when the conventional compressor shown in Fig. 1 and the compressor of the present invention are each filled with 150 cc of lubricating oil, when the refrigerant flow rate is C kg/h, the conventional compressor The oil circulation rate of the compressor of the present invention is B%, whereas that of the compressor of the present invention is A%, which means that the oil circulation rate of the compressor of the present invention is reduced by about 50 factors compared to the conventional compressor. I understand.

FIG. 7 is an oil circulation rate-refrigeration capacity characteristic diagram C of the conventional compressor shown in FIG. 1 and the compressor of the present invention.

As shown in Figure 7, the refrigeration capacity when the oil circulation rate is 0φ is 1
Then, the refrigerating capacity of the conventional compressor is 0.87, while that of the compressor of the present invention is 0.97. From the formula below, the refrigerating capacity of the compressor of the present invention is equal to that of the conventional compressor. It can be seen that the rate is about 11% higher than that.

Note that by reducing the amount of lubricating oil sealed in the conventional compressor shown in FIG. 1, the oil circulation rate shown by the symbol B in FIGS. 6 and 7 can be lowered. However, if the amount of lubricating oil sealed in the conventional compressor shown in Fig. 1 is reduced from, for example, 150 CC to 100 CC, the lubricating oil for the swash plate 2 and other sliding parts of the compressor will become insufficient. As a result, the amount of heat generated increases and the temperature of the refrigeration cycle rises significantly, which is not preferable in terms of maintaining the durability of the compressor. On the other hand, in the present invention, as shown by the symbol A in FIGS. 6 and 7, the oil circulation rate during the refrigeration cycle can be lowered than before, so that the lubricating oil sealed in the compressor can be reduced. Even if the amount is, for example, 150 cc, a larger amount of lubricating oil is stored in the swash plate chamber 7 than in the past, and the oil in the swash plate chamber 7 is constantly maintained by the pouring action of the swash plate 2. It functions to lubricate the compressor sliding parts and suppress heat generation in the compressor sliding parts.
It is possible to suppress the temperature rise of the frozen cycle within a small range and maintain good durability of the compressor.

In order to improve the refrigeration loss of the conventional compressor shown in Fig. 1, it is possible to increase the capacity of the compressor, but in this case, the compressor itself becomes It is also necessary to increase the capacity of related equipment such as condensers and evaporators, and a significant increase in costs is unavoidable. However, in the present invention, the refrigerating capacity can be significantly improved by simply changing the design of a part of the compressor, and there is no need to increase the capacity of related equipment such as condensers and evaporators. It is also excellent in many respects.

FIG. 8 shows an embodiment in which the refrigerant suction structure according to the present invention is applied to a swash plate compressor in which an outer shell and a cylinder bore forming body form an integral structure. In this embodiment, the low-pressure refrigerant containing oil enters the swash plate chamber 7 through the low-pressure refrigerant suction port 5 opened in the rear cylinder block 1'. Thereafter, the oil passes through the low pressure passage 19.19' provided near the rotating shaft 3, where the oil content decreases due to the centrifugal separation effect caused by the rotation of the swash plate 2, and then passes through the low pressure chamber 18.18.
'Flow into.' Therefore, this embodiment also has the same effect as the embodiment shown in FIG. 3, and it is possible to obtain a compressor with excellent refrigerating ability while reducing the oil circulation rate and maintaining durability.

(12) [Effects of the Invention] As detailed above, according to the present invention, by adopting a structure completely different from the conventional one, oil in the swash plate chamber can be prevented from flowing into the low pressure chamber side connected to the swash plate chamber. It is possible to prevent this as much as possible and reduce the amount of lubricating oil flowing into the refrigeration cycle. Being able to reduce the amount of lubricating oil flowing into the refrigerant cycle means that there is no need to change the mechanism. This means that the oil circulation rate of the refrigeration cycle is reduced, and as a result, it is possible to obtain a swash plate compressor with excellent refrigeration capacity that improves the relationship between the oil circulation rate of the refrigeration cycle and the refrigerant flow rate compared to the conventional one. .

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing the internal structure of a conventional swash plate compressor that has been put into practical use; FIG. 2 is a vertical sectional view showing the internal structure of a swash plate compressor previously proposed by the applicant; FIG. 3 is a longitudinal sectional view of the internal structure of an embodiment of the swash plate compressor according to the present invention, FIG. 4 is a view taken along the Z arrow in FIG. 3, and FIG. 5(a)
and (b) are diagrams explaining the flow (13) directions of refrigerant and lubricating oil in a part of the compressor. Oil circulation rate characteristic diagram, 7th
The figure is an oil circulation rate-refrigeration capacity characteristic diagram of the conventional compressor shown in FIG. 1 and the compressor of the present invention, and FIG. 8 is a drawing showing another embodiment of the present invention. ■ and 1'... Cylinder block, 2... Swash plate, 3... Compressor rotating shaft, End... Low pressure refrigerant suction port, 6...
...Casing, 7...Swash plate chamber, 8 and 8'...
Partition wall, 9.9'...Partition wall, 10.10'...Low pressure passage, 11.11'...Low pressure chamber, 12.12'...
・Partition wall, 13.13'...Low pressure passage, 14.14'
...Low pressure chamber, 15.15'...Oil filled, 17.17'
...Partition wall, 18.18'...Low pressure chamber, 19.19
'...Low pressure passage, L...Lubricating oil, R...Refrigerant. Agent Patent attorney Hiroo Nagasaki (and 1 other person) (14) (?-) Figure 2 Figure 7

Claims (1)

[Claims] 1. Mixing lubricating oil into the refrigerant circulating in the refrigeration cycle,
In the swash plate compressor, which has a structure in which the refrigerant containing lubricating oil is guided into the swash plate chamber and sprayed directly onto the compressor sliding parts, the low pressure passage leading from the swash plate chamber to the low pressure chamber is located near the compressor rotation axis. A swash plate compressor characterized in that the compressor is provided through a partition wall that partitions a swash plate chamber and a low pressure chamber. 2. A shell plate compressor according to the invention as set forth in claim 1, in which the wall thickness around the low pressure passage leading from the swash plate chamber to the low pressure chamber is thicker than the wall thickness of the surrounding partition wall. 3. In the invention as set forth in claim 1 or 2, the swash plate compressor has a refrigerant flow path in the low pressure chamber as a detour.