JP3758237B2 - Lubrication mechanism for reciprocating compressors - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in lubrication of a radial bearing that supports a drive shaft of a reciprocating compressor.
[0002]
[Prior art]
Among conventional swash plate compressors, for example, in a swash plate compressor in which a swash plate chamber communicates with a suction port as disclosed in Japanese Patent Laid-Open No. 3-92587, suction gas is sucked into the swash plate chamber together with feedback oil, and the drive shaft It is sucked into the suction chamber of the cylinder head through a plurality of suction passages provided in the peripheral part in parallel with the drive shaft, and sucked into the cylinder bore through the suction chamber.
Thus, in the swash plate compressor, the front and rear cylinder blocks have communication passages that connect the suction gas passage and the drive shaft hole to supply lubricating oil to the radial bearing that supports the drive shaft. A portion of the suction gas that flows through the suction passage is fed into the drive shaft hole, and is sent to the suction chambers of the front and rear cylinder heads via radial bearings. The lubrication mechanism was such that oil was supplied to the radial bearing.
[0003]
[Problems to be solved by the invention]
However, in this swash plate type compressor, since the refrigerant passage from the communication passage through the radial bearing of the drive shaft hole is a bypass passage having a large resistance, the suction gas is hardly supplied to the drive shaft hole. There was a problem that it was difficult to lubricate.
In particular, alternative chlorofluorocarbons are being adopted in recent years. For example, in the case of a refrigerator cooler, the refrigerant is changed from R502 to R404a (mixed refrigerant of R125, R143a, and R134a), resulting in a shaft made of high carbon steel. As a result, the sliding characteristics of high-chromium steel rollers with radial bearings have been reduced, and it has become desirable to improve the lubrication function of radial bearings.
[0004]
The present invention has been made in view of such problems existing in the prior art, and improves the lubrication function of a radial bearing that rotatably supports a drive shaft.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, there is provided a drive shaft for rotationally driving the cam plate, a drive shaft hole penetrating through the center of the cylinder block, and the drive shaft hole disposed in the drive shaft hole. A radial bearing for rotating and supporting the drive shaft, a suction port for introducing a return refrigerant gas, a crank chamber connected to the suction port, a plurality of suction passages communicating the crank chamber and a suction chamber of the cylinder head, and the suction passage; And a communication passage that communicates with the drive shaft hole, and is configured to suck suction gas into the cylinder bore through the suction port, the crank chamber, the suction passage, and the suction chamber in order, and A part of the suction gas flowing through the passage is sent from the communication passage to the suction chamber via the radial bearing, and lubricating oil is supplied to the radial bearing portion. In reciprocating compressor constructed in, at least one passageway of said suction passage communication passage is connected, it is provided with a oil introduction means for sending aggressively suction gas into the passageway.
[0006]
According to a second aspect of the present invention, the oil introducing means is provided in a suction passage closest to the suction port among suction passages to which the communication passage is connected.
According to a third aspect of the present invention, the oil introducing means is a closing or restricting member disposed closer to the cylinder head than a position where the communication passage is connected to the suction passage.
According to a fourth aspect of the present invention, the communication passage is a concave groove formed on the end face on the swash plate chamber side of the cylinder block.
[0007]
Therefore, in the compressor configured as described above, during operation, the suction gas introduced from the suction port into the swash plate chamber is sucked into the suction chamber of the cylinder head via the suction passage, In a suction passage provided with a closing or restricting member (Claim 3) which is a preferred form, all or most of the suction gas actively flows toward the radial bearing for supporting the drive shaft, and the lubrication contained in this suction gas Oil is supplied to the radial bearing portion, and the radial bearing portion is lubricated.
Further, as described in claim 2, by making the suction passage provided with the oil introduction means closest to the suction port, the intake gas immediately after entering the swash plate chamber having a high lubricating oil content is directly used as the oil introduction means. The lubricating function of the radial bearing portion is further improved.
Furthermore, as described in claim 4, by providing a concave groove connecting the suction passage and the drive shaft hole on the crank chamber side end surface of the cylinder block, the communication path can be replaced with the concave groove, The hole machining can be changed to the groove grooving, and the machining cost can be reduced.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the present invention is embodied in a swash plate compressor will be described with reference to FIGS.
1 is a longitudinal sectional view of a double-headed swash plate compressor, and FIG. 2 is a sectional view taken along the line II-II in FIG. 1, and is a view of a cylinder block as viewed from the swash plate chamber side. 3 is a cross-sectional view taken along the line III-III in FIG. 2, and is a main part of the embodiment of the present invention.
[0009]
As shown in FIG. 1, both ends of cylinder blocks 1 and 2 facing each other are closed by front and rear cylinder heads 5 and 6 via valve plates 3 and 4, respectively. 7 is connected and fixed. A swash plate chamber 8 serving as a crank chamber is formed at the joint between the cylinder blocks 1 and 2, and the drive shaft holes 1 a and 2 a penetrating the centers of the cylinder blocks 1 and 2 are driven by radial bearings 9. A shaft 10 is rotatably supported, and a swash plate 11 serving as a cam plate is accommodated in the swash plate chamber 8 while being fitted to the drive shaft 10.
[0010]
In the cylinder blocks 1 and 2, five pairs of cylinder bores 12 are formed in radial positions parallel to the drive shaft 10 and centered on the drive shaft 10, and pistons 13 of both heads are slidably accommodated in each cylinder bore 12. ing. Each piston 13 is moored to the swash plate 11 via a shoe 14, and is reciprocated in the cylinder bore 12 by a swing of the swash plate 11 as the drive shaft 10 rotates, so that a compression operation is performed. A thrust bearing 15 is interposed between both end surfaces of the boss 11 a of the swash plate 11 and the cylinder blocks 1 and 2.
[0011]
The cylinder heads 5 and 6 are respectively formed with suction chambers 16 and 17 on the center side and discharge chambers 18 and 19 on the outer peripheral side. The swash plate chamber 8 communicates with the suction chambers 16 and 17 by suction passages 20 and 21 disposed between the cylinder bores 12. Further, the swash plate chamber 8 is connected to a refrigerant circuit (not shown) through a suction port 22 and the discharge chambers 18 and 19 through a discharge port 23, respectively.
The valve plates 3 and 4 are formed with suction ports 25 and 26 for communicating the suction chambers 16 and 17 and the cylinder bore 12, and discharge ports 27 and 28 for communicating the discharge chambers 18 and 19 and the cylinder bore 12, respectively. Yes. Furthermore, suction valves 29 and 30 for opening and closing the suction ports 25 and 26 are provided on the cylinder bore 12 side of the valve plates 3 and 4, and discharge valves 31 for opening and closing the discharge ports 27 and 28 are provided on the discharge chambers 18 and 19 side. 32 are provided.
[0012]
Thus, as shown in FIG. 2, the suction passage 21 is a peripheral portion of the drive shaft 10 in the rear cylinder block 2, and is located in the middle portion of the five cylinder bores 12 in parallel with the drive shaft 10. Five are arranged. Further, in each of the suction passages 21, a communication hole 21 a as a communication path that connects the suction passage 21 and the drive shaft hole 2 a is provided to be inclined from the swash plate chamber 8 side toward the rear cylinder head 6. As shown in FIG. 3, the suction passage 21A closest to the suction port 22 has a plug member 211 as a closing member which is an oil introduction means for actively sending suction gas to the communication hole 21a on the cylinder head side of the communication hole 21a. It is blocked by press-fitting.
[0013]
Such a suction passage 21A is a main part of the present embodiment, but a suction path 20A similar to this is formed also on the front side, and this also forms a main part of the present embodiment.
That is, in the front cylinder block 1 as well, five suction passages 20 are arranged in the vicinity of the drive shaft 10 in the same manner as the suction passage 21 on the rear side (not shown, but the suction passage 21 with the swash plate chamber 8 as a boundary). And a communication hole 20a as a communication path communicating with the drive shaft hole 1a is provided in the suction path 20 in an inclined manner like the communication hole 21a. The suction passage 20A closest to 22 is closed on the front cylinder head 5 side by a plug member, like the suction passage 21A.
[0014]
In the swash plate type compressor configured as described above, the refrigerant gas returned from the external refrigerant circuit to the compressor is the suction port 22 → swash plate chamber 8 → suction passages 20, 21 → suction chambers 16, 17 → cylinder bore 12 → It flows in the order of the discharge chambers 18 and 19 and is sent out to the external refrigerant circuit through the discharge port 23. Then, the lubrication of the sliding portion around the shoe 14 or around the piston 13 that transmits the rotational motion of the thrust bearing 15 and the swash plate 11 to the piston 13 as reciprocating motion is performed by the oil contained in the mist form in the refrigerant gas. To be done.
[0015]
In particular, the radial bearing 9 that supports the drive shaft 10 introduces suction gas into the drive shaft holes 1a and 2a from the communication holes 20a and 21a provided in the suction passages 20 and 21, and is contained in the suction gas. Lubricating is performed by the mist-like lubricating oil. Furthermore, since some of the suction passages 20A and 21A are closed on the cylinder head side, the suction gas is forcibly sent to the drive shaft holes 1a and 2a and is sucked into the suction chamber via the radial bearing 9. 16 and 17, the mist-like lubricating oil contained in the suction gas is efficiently supplied to the radial bearing 9 and the lubricating performance is improved.
[0016]
In particular, as described above, the suction passages 20A and 21A that close the cylinder head side are selected to be closest to the suction port 22, so that the intake gas immediately after flowing into the swash plate chamber 8 containing a high concentration of lubricating oil The air is sucked into the suction passages 20A and 21A as they are, and the lubricating oil is efficiently supplied through the suction passages 20A and 21A. FIG. 4 shows the result of the wear resistance test comparing the conventional compressor and the compressor according to the present embodiment. As shown in FIG. 4, the lubrication performance is remarkably improved. That is, in FIG. 4, the vertical axis represents the shaft wear amount, the horizontal axis represents the durability time, and the shaft wear amount at the time when the shaft wear amount becomes substantially constant is about 1 / of that of the conventional product in this embodiment. 9
[0017]
Next, a second embodiment will be described with reference to FIGS.
5 is a cross-sectional view corresponding to FIG. 2, FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5, and is an enlarged cross-sectional view of a main part corresponding to FIG. Thus, as shown in these drawings, the suction passage 21A and the drive shaft hole 2a are communicated with each other at the end surface of the cylinder block 1, 2 on the swash plate chamber 8 side by a concave groove 21b as a communication passage. In this embodiment, by providing the concave groove 21b, the previous communication hole 21a can be omitted.
That is, in place of the communication hole 21a, the concave groove 21b is provided, and the processing of the concave groove 21b is cheaper than the processing of the communication hole 21a.
[0018]
In any of the above embodiments, the conventional cylinder block of final finish or intermediate finish can be diverted, so there is a cost merit of common parts in production equipment, production parts management, spare parts management, etc. In either case of changing the model or changing only a part of the model such as a compressor for a freezing vehicle, it is easy to cope with any case.
[0019]
Although the embodiment of the present invention has been described with reference to FIGS. 1 to 6, the embodiment can be modified and embodied as follows.
(1) The swash plate type compressor as the reciprocating compressor is not limited to the double-headed type, and other types such as a single-headed type (for example, a wave cam type) as long as the swash plate chamber 8 communicates with the suction port 22. Etc.).
(2) The present invention is not limited to the suction passages 20A and 21A provided with a closing member, but a method in which a suction member is provided in the suction passages 20A and 21A, for example, a small hole is formed in the center of the plug member, Some of the suction gas refrigerant is circulated from the suction passages 20A and 21A to the suction chambers 16 and 17 of the cylinder heads 5 and 6 through the small holes, and the remaining suction gas is circulated through the drive shaft holes 1a and 2a. Is included.
(3) As a method of providing a blocking member or a throttle member in the suction passage, the plug member may be welded or bonded instead of the plug member press-fitting. Furthermore, it is also possible to integrate these closing or restricting members into the cylinder block.
(4) The number of suction passages provided with the blocking or throttling member is not limited to one but may be plural.
[0020]
【The invention's effect】
Since this invention is comprised as mentioned above, there exist the following effects.
According to the first or third aspect of the present invention, in the suction passage provided with the oil introduction means (preferably, the blockage or throttle member), the suction gas flowing through this passage actively flows to the drive shaft side, so that the drive is performed. Lubrication of the radial bearing that supports the shaft is efficiently performed.
[0021]
According to the second aspect of the present invention, since the oil introduction means is provided on the cylinder head side of the suction passage closest to the suction port, the suction gas portion having a high lubricating oil concentration immediately after flowing into the crank chamber is provided. The oil is introduced into the suction passage provided with the oil introduction means, and the lubricating oil is supplied to the radial bearing more efficiently.
[0022]
According to the fourth aspect of the present invention, a concave groove for connecting the suction passage and the drive shaft hole is provided on the crank chamber side end surface of the cylinder block as the communication passage for communicating the suction passage and the drive shaft hole. , Processing costs are reduced.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a swash plate compressor according to a first embodiment.
FIG. 2 is a cross-sectional view taken along line II-II in FIG.
3 is a cross-sectional view taken along line III-III in FIG.
FIG. 4 is a result of a durability test of the first embodiment. FIG. 5 is a longitudinal sectional view of a swash plate compressor according to the second embodiment.
6 is a cross-sectional view taken along line VI-VI in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Front side cylinder block, 2 ... Rear side cylinder block, 1a, 2a ... Drive shaft hole, 5 ... Front side cylinder head, 6 ... Rear side cylinder head, 8 ... Swash plate chamber, 9 ... Radial bearing, 10 ... Drive shaft 11 ... Swash plate, 12 ... Cylinder bore, 14 ... Shoe, 15 ... Thrust bearing, 16, 17 ... Suction chamber, 20, 21 ... Suction passage, 20A, 21A ... Suction passage closest to the suction port, 20a, 21a ... Station Communication holes as passages, 20b, 21b ... concave grooves, 22 ... suction port, 211 ... plug member as oil introducing means.

Claims (4)

A drive shaft for rotationally driving the cam plate, a drive shaft hole penetrating through the center of the cylinder block, a radial bearing disposed in the drive shaft hole to rotatably support the drive shaft, a suction port for introducing return refrigerant gas, A crank chamber communicated with the suction port; a plurality of suction passages communicating the crank chamber with a suction chamber of the cylinder head; a communication passage communicating the suction passage with the drive shaft hole; A suction passage for sucking the suction gas into the cylinder bore through the crank chamber, the suction passage, and the suction chamber in order, and a part of the suction gas flowing in the suction passage from the communication passage through the radial bearing. In the reciprocating compressor configured to send to the suction chamber and supply lubricating oil to the radial bearing portion, the communication path is connected. At least one passageway, lubricating mechanism of a reciprocating compressor which is characterized by comprising an oil introducing means for sending aggressively suction gas into the passageway of said suction passage. 2. The lubrication mechanism for a reciprocating compressor according to claim 1, wherein the oil introduction means is provided in a suction passage closest to the suction port among suction passages to which the communication passage is connected. 3. The reciprocating motion according to claim 1, wherein the oil introducing means is a closing or restricting member disposed closer to the cylinder head than a position where the communication passage is connected to the suction passage. Lubricating mechanism of mold compressor. The lubrication mechanism for a reciprocating compressor according to any one of claims 1 to 3, wherein the communication path is a concave groove formed in an end surface on a swash plate chamber side of the cylinder block.

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