JP2760056B2 - Swash plate compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a forced lubrication type swash plate type compressor equipped with an oil tank and an oil supply pump, and more specifically, to prevent outflow of lubricating oil stored in the machine. It relates to the intended improvement of the compressor.

[Prior Art] As shown in FIG. 4, a swash plate type compressor which is already in practical use has front ends of cylinder blocks 1 and 2 joined to each other through valve plates 3 and 4 as shown in FIG. A swash plate chamber 7 is formed in the cylinder blocks 1 and 2 and communicates with a lubrication storage oil tank 8 provided below the swash plate chamber 7. A drive shaft 9 is rotatably supported at the center of the cylinder blocks 1 and 2, and a swash plate 10 fixed on the drive shaft 9 is accommodated in the swash plate chamber 7. Multiple bores 12 in cylinder blocks 1 and 2
Is formed around the drive shaft 9, and a double-headed piston 13 is reciprocally slidably fitted in each bore 12, and is moored to the swash plate 10 by intervention of a shoe 14.

In the compressor, the cylinder blocks 1 and 2
In order to lubricate the thrust bearing 11 and the shoe 14 interposed between the drive shaft 9 and the
A forced lubrication system provided with a lubrication pump 15 that is operated by the rotation of. In this system, the lubricating oil is pumped from the oil tank 8 into the pump chamber 19 by the operation of the lubricating pump 15, and the lubricating oil is supplied to the thrust bearing 11 via the lubricating passage 20 formed in the drive shaft 9. Has been made.

[Problems to be Solved by the Invention] In the swash plate type compressor described above, it is desirable that the pressure in the swash plate chamber 7 is equal to the pressure on the suction side. The pressure in 7 is considerably higher than the suction side pressure. The swash plate chamber 7 and the suction chamber 21 formed in the front housing 5 are in communication with each other via a shaft circumferential passage 23 including a radial bearing, but this alone is insufficient to eliminate the pressure difference between the two chambers. Therefore, for example, an equilibrium passage 24 that connects the swash plate chamber 7 or the oil tank 8 to the suction chamber 21 is provided.

The equilibrium passage 24 is formed by a fitting play 24a of a through bolt 26 formed in the cylinder block 1 and a vertical groove 24b formed on the outer end surface of the cylinder block 1 so as to be continuous with the fitting play 24a. It is illustrated as such.

However, in the above-described forced refueling method, the drive shaft 9 is, for example, 50
When the swash plate chamber 7 and the suction side are rotated at a high speed of 00 rpm or more, the pressure difference between the swash plate chamber 7 and the suction side becomes extremely large, and the shaft circumferential gap passage 23 and the equilibrium passage which communicate the swash plate chamber 7 (oil tank 8) with the suction side The high-density lubricating oil flows out of the swash plate chamber 7 into the refrigerant passage together with the refrigerant gas via the refrigerant gas 24. As a result, insufficient lubricating oil storage results in poor lubrication in each sliding part, and the lubricating oil that has flowed into the refrigerant passage in the machine is discharged from the discharge chamber 25 together with the refrigerant gas to the refrigeration circuit. There is a problem that the refrigeration efficiency is reduced by adhering to an evaporator or the like.

An object of the present invention is to solve the problem of preventing lubricating oil stored in a compressor from flowing out.

[Means for Solving the Problems] The invention according to claim 1 for solving the above problems is to provide an oil separation chamber in an equilibrium passage communicating the swash plate chamber and the suction chamber, and through a narrow gap from the swash plate chamber. The invention is characterized in that a return oil passage connecting the shaft clearance passage connected to the suction chamber and the equilibrium passage is provided. It is characterized by having an oil separation chamber.

The equilibrium passage is not limited to the communication configuration between the swash plate chamber and the suction chamber, but may be implemented in a form in which the oil tank communicates with the suction chamber.

[Operation] Accordingly, when the drive shaft rotates at high speed and the pressure in the swash plate chamber is increased by blow-by gas from the bore, most of the refrigerant gas containing mist-like lubricating oil in the swash plate chamber passes through the equilibrium passage. To the oil separation chamber. When this refrigerant gas enters the oil separation chamber from the inlet portion of the equilibrium passage having a relatively small cross-sectional area, the lubricating oil particles mixed together with a slow speed are separated, and the refrigerant gas continues to flow through the outlet portion of the equilibrium passage due to the pressure difference. While being introduced into the suction chamber, the separated lubricating oil flows back through the equilibrium passage and returns from the entrance of the passage to the swash plate chamber and the oil tank.

On the other hand, some oil-containing refrigerant gas flows to the suction chamber through the very narrow space between the thrust bearing and the shaft circumferential path, but this path is originally small in flow rate, so that the size of the mixed lubricating oil particles is large. The part is separated, guided from the bottom wall of the coaxial circumferential passage to the equilibrium passage through the return oil passage, and returned to the swash plate chamber and the oil tank similarly to the above-described separated oil. In the case where the auxiliary oil separation chamber connected to the oil return passage is provided in the shaft circumferential passage, the oil component is recovered at a higher ratio from the refrigerant gas flowing through the passage.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In the present embodiment, the fitting clearance 24a of the through bolt 26 forming the equilibrium passage 24 is configured as the oil separation chamber 30 by being greatly expanded leaving a part of the inlet portion, and
Conventionally, a return oil passage 31 newly drilled from the lower bottom wall of the shaft circumferential passage 23 along the outer periphery of the radial bearing 22 is connected to the above-mentioned extended portion of the vertical groove 24b. There is a big feature different from. Since the remaining configuration is substantially the same as that of the conventional apparatus, the same portions and the same portions are denoted by the same reference numerals and detailed description thereof will be omitted.

Therefore, according to the present embodiment, when the pressure in the swash plate chamber 7 rises due to the cumulative increase of blow-by gas from the bore 12 accompanying the high-speed rotation of the drive shaft 9, the swash plate chamber 7 and the low-pressure system including the suction chamber 21 communicate with each other. The pressure gradient becomes large, and most of the refrigerant gas containing the mist-like lubricating oil in the swash plate chamber 7 flows to the suction chamber 21 via the equilibrium passage 24. At this time, the refrigerant gas flows from the inlet of the fitting play gap 24a having a relatively small cross-sectional area to the oil separation chamber 30.
When entering, the oil particles having a large specific gravity are separated from the refrigerant gas and stagnate on the bottom wall of the chamber due to an extremely large cross-sectional area of the passage. The refrigerant gas is thereafter guided from the vertical groove 24b to the suction chamber 21 according to the pressure gradient, and the retained lubricating oil flows in the opposite direction and flows from the entrance of the fitting play gap 24a to the swash plate chamber 7 and the oil tank 8. Will be returned.

On the other hand, some oil-containing refrigerant gas flows from the narrow gap between the thrust bearing 11 and the drive shaft 9 to the suction chamber 21 through the shaft circumferential passage 23 including the radial bearing 22, Since this passage has a small flow rate, most of the oil particles mixed in the refrigerant gas are separated by the cross-sectional area difference between the narrow gap portion and the shaft circumferential passage 23, and the bottom of the shaft circumferential passage 23 is separated. Staying on the wall,
The retained lubricating oil is guided from the bottom wall to the return oil passage 31 and flows down the vertical groove 24b, and then flows through the bottom wall of the oil separation chamber 30 like the separation oil in the above-described path to form a fitting clearance. It is returned to the swash plate chamber 7 and the oil tank 8 from the entrance of 24a.

In another embodiment shown in FIG. 3, an annular auxiliary oil separation chamber 32 is further provided in the shaft circumferential passage 23 so that oil separation is positively performed also for the refrigerant gas flowing through this passage. The return oil passage 31 'for guiding the separated lubricating oil is configured to directly communicate the sub oil separation chamber 32 with the oil separation chamber 30.

Accordingly, in this embodiment, oil separation of the refrigerant gas flowing from the swash plate chamber 7 to the suction chamber 21 is forcibly performed in both the equilibrium passage 24 and the shaft circumferential passage 23, so that the lubricating oil is removed. Outflow can be more effectively prevented.

[Effects of the Invention] As described above in detail, the present invention provides an oil separation chamber in the equilibrium passage among the paths in which the oil-containing refrigerant gas in the swash plate chamber flows to the low-pressure system due to the pressure gradient. The lubricating oil is stored in the shaft oil passage where the oil particles are separated and the oil is actively or passively separated. Outflow from the machine can be effectively suppressed, and poor lubrication of each sliding portion and a decrease in refrigeration efficiency can be reliably prevented.

[Brief description of the drawings]

1 is a sectional front view of a swash plate type compressor according to one embodiment of the present invention, FIG. 2 is a cutaway sectional view taken along line II-II of FIG. 1, and FIG. 3 is a sectional view of another embodiment of the present invention. Sectional front view of a swash plate type compressor,
FIG. 4 is a sectional front view of a conventional swash plate type compressor. 7 ... swash plate chamber, 8 ... oil tank 9 ... drive shaft, 10 ... swash plate 21 ... suction chamber, 23 ... shaft clearance passage 24 ... equilibrium passage, 30 ... oil separation chamber 31, 31 ' …… Return oil passage, 32 …… Secondary oil separation chamber

Continuation of the front page (72) Inventor Hitoshi Inukai 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (56) References JP-A-57-26285 (JP, A) JP-A-56-2481 (JP, a) JP Akira 50-74803 (JP, a) JP Akira 49-108610 (JP, a) JitsuHiraku Akira 54-155615 (JP, U) (58 ) investigated the field (Int.Cl. ⁶ , DB name) F04B 27/08

Claims (3)

(57) [Claims] 1. A cylinder block, a housing for closing both ends of the cylinder block via a valve plate, a drive shaft inserted through and supported by the cylinder block, and a swash plate on the drive shaft for mooring to move directly in the bore. A swash plate type compressor having a piston, a swash plate chamber internally provided to accommodate the swash plate, and an oil tank connected to a lower portion thereof, and a suction chamber formed in the housing. A swash plate type in which an oil separation chamber is provided in an equilibrium passage that communicates with the swash plate chamber, and a return oil passage that connects the shaft passage and the equilibrium passage connected to the suction chamber through a narrow gap from the swash plate chamber is provided. Compressor. 2. A swash plate type compressor according to claim 1, wherein an annular auxiliary oil separation chamber connected to said oil return passage is formed in said shaft circumferential passage. 3. The swash plate compressor according to claim 1, wherein said narrow space is formed between a thrust bearing and a drive shaft.