JPS5855355B2 - compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to compressors, and particularly to lubrication of sliding parts such as bearings in compressors for vehicle air conditioning.

In compressors for vehicle air conditioning, part of the refrigerant gas mixed with lubricating oil is diverted from the main passage and guided to the swash plate chamber or crank chamber (hereinafter simply referred to as the crank chamber), or all of the refrigerant gas is diverted from the main passage. By guiding the oil into the crank chamber, it lubricates sliding parts such as bearings.

However, in the case of a type in which part of the refrigerant gas is introduced,
When the amount of refrigerant gas sealed in the circuit becomes insufficient due to gas leaks, the amount of oil in the refrigerant gas that flows into the crank chamber naturally decreases, which interferes with the lubrication of sliding parts and causes seizure. Furthermore, even if there is a sufficient amount of refrigerant gas in the circuit, it takes some time at startup for the oil to be sufficiently introduced to the sliding parts that need to be lubricated along with the refrigerant gas in the circuit. During this period, there was a tendency to run out of lubricating oil.

In addition, in the case of a type in which all of the refrigerant gas is introduced into the crank chamber, there is a tendency for excessive lubrication during normal operation, and the oil density in the crank chamber is high. There have been problems such as oil backflow and a drop in performance due to high suction resistance.

The present invention eliminates the above-mentioned drawbacks of conventional compressors, and provides good lubrication of sliding parts not only during normal operation but also when the amount of refrigerant gas in the circuit is insufficient. The purpose is to provide an improved compressor.

Hereinafter, illustrated embodiments embodying the present invention will be described in detail.

First, a first embodiment implemented in a swash plate type compressor shown in FIGS. 1 to 4 will be described.

The front and rear cylinder blocks IP and IR that constitute the main body of the compressor have three cylinder bores 2 arranged at equal intervals in the circumferential direction and a sub-suction chamber 3 formed between the cylinder bores 2. , a discharge control chamber 4 and an oil reservoir chamber 5.

At one side of the front cylinder block 1F located at the center of both cylinder blocks IP and IR, there is a suction passage 7 that communicates with the sub-suction chamber 3 and the swash plate chamber 6, respectively.
The suction passage 7 is divided by a partition wall 8 into a passage 7a communicating with the sub-suction chamber 3 and a passage 7b communicating with the swash plate chamber 6.

Further, a discharge passage 9 communicating with the secondary discharge chamber 4 is provided on the other side of the cylinder block 1F.

Suction holes 10 corresponding to the suction passage 7 and discharge passage 9 are provided in the upper part of the front cylinder block 1F.
A connecting pipe member 12 having a discharge hole 11 is fixed thereto.

A valve 13 is rotatably supported in the suction hole 10 by a bottle 14 for controlling the amount of refrigerant gas divided from the suction hole 10 through the suction passage 7 to the sub-suction chamber 3 and the swash plate chamber 6. In this embodiment, the opening/closing operation of the throttle valve 13 is performed through the discharge hole 1.
It is controlled by the discharge pressure within 1.

That is, a bellows 16 made of metal (may be made of rubber or synthetic resin) that expands and contracts according to the discharge pressure in the discharge hole 11 is housed in a chamber 15 provided in a part of the discharge hole 11, and The bellows 16 and the valve 13 are connected via an interlocking ring 18 inserted into a horizontal hole 17 provided between the discharge hole 11 and the suction hole 10.

The valve 13 and the interlocking rod 18 are connected by a pin 19, and the pin 19 is slidable into an elongated hole 20 at the bottom of the valve 13.

Therefore, when the discharge pressure inside the discharge hole 11 is high, the bellows 1
6 contracts, the valve 13 becomes almost in an upright state as shown by the solid line in FIG. Due to the expansion, the valve 13 tilts as shown by the imaginary line in FIG. 3, and most of the refrigerant gas is introduced into the swash plate chamber 6 side.

Note that 21 is a stopper for the valve 13. The outer ends of both cylinder blocks IP and IR are connected to the cylinder housing 2 with valve plates t-22F and t-22R interposed therebetween, respectively.
3F and 23R are installed, and this cylinder housing 23F.

23R is the suction chamber 24F, 24R and discharge chamber 25F, respectively.
, 25R.

In addition, the drive shaft 26 of the compressor has both cylinder flocks 1F,
The rotation of the swash plate 29, which is rotatably supported at the center of the IR via a radial bearing 27 and is keyed to the drive shaft 26 and supported by a thrust bearing 28, causes a shoe to be attached to the swash plate 29. A piston 32 assembled via a piston 30 and a ball 31 is reciprocated within the cylinder bore 2.

This embodiment is constructed as described above, and its operation will be explained below.

First, a description will be given of operation when a specified amount of refrigerant gas is sealed in the circuit.

In this case, the reciprocating movement of the piston 32 causes the discharge port 33F of the valve plate 22F22R to flow from the cylinder bore 2,
33R, into the discharge chambers 25F and 25R, and further discharged from this to the condenser (not shown) side via the discharge control chamber 4, discharge passage 9, and discharge hole 11, the discharge pressure is high. The bellows 16 contracts and the valve 13 stands up.

Therefore, the refrigerant gas flowing in from the suction hole 10 is divided by the valve 13, and most of it flows from the suction passage 7a to the sub-suction chamber 3 and the suction ports 34F of the valve plates 1-22F and 22R.

34R into the suction chambers 24F and 24R, while a portion of the refrigerant gas required for lubrication flows into the suction passage 7.
It flows into the swash plate chamber 6 through b.

Then, this refrigerant gas flows through the shoe 30, the hole 31, as shown by the arrow in the figure. By flowing into the suction chambers 24F, 24R or the sub-suction chamber 3 through the locations where sliding members such as the thrust bearing 28 and radial bearing 27 are present, the oil in the refrigerant gas lubricates the sliding members without excess or deficiency. It will be done.

Next, we will explain startup when a specified amount of refrigerant scum is sealed in the circuit. In this case, the sliding members are temporarily lubricated by residual oil, but refrigerant from the evaporator (not shown) side It takes some time for the gas to return to the compressor, so the sliding members tend to be under-lubricated.

However, until the refrigerant gas returns sufficiently, the discharge pressure of the discharge system does not increase significantly, so the hollow 16 expands and tilts the valve 13 to close or throttle the passage 7a leading to the sub-suction chamber 3.

Therefore, most of the refrigerant gas returning from the evaporator side flows into the swash plate chamber 6, thereby preventing insufficient lubrication of each sliding member.

In addition, immediately after the compressor is started, the oil accumulated in the evaporator may flow into the compressor in a liquid state, but in this case as well, the oil flows into the swash plate chamber 6, so that the swash plate chamber 6 temporarily closes. As it becomes a sub-oil reservoir chamber, oil also easily reaches the oil reservoir chamber 5, preventing a large amount of oil from flowing into the suction chambers 24F and 24R, and making it difficult for liquid compression to occur.

Next, the case where the amount of refrigerant gas sealed in the circuit is insufficient will be explained.

In this case, the discharge pressure in the discharge system decreases compared to normal due to the lack of refrigerant gas, so the extension of the bellows 16 causes the valve 13 to tilt, thereby closing or restricting the passage 7a leading to the sub-suction chamber 3. .

Therefore, most of the refrigerant scum that returns to the compressor flows into the suction chambers 24F and 24R via the swash plate chamber 6, so even if the absolute amount of refrigerant gas is insufficient, each sliding member in the swash plate chamber 6 The oil necessary for lubrication is supplied sufficiently to prevent the seizure phenomenon.

Next, a second embodiment implemented in the crank type compressor shown in FIGS. 5 and 6 will be described.

This embodiment shows a vertical two-cylinder cylinder, and a cylinder housing 23 having a suction chamber 24 and a discharge chamber 25 for refrigerant gas is fixed to the upper end surface of the cylinder block 1 (or crankcase) via a pulp plate 22. A piston 32 that reciprocates vertically within two cylinder bores 2 (only one is shown in the figure) formed in the cylinder block 1 moves from the drive shaft 26 to the crankshaft 35.
and is driven via the connecting iron 36.

A part of the suction chamber 24 communicating with the suction hole 10 provided in a part of the cylinder housing 23 is a suction passage 7, and this suction passage 7 has a suction hole as in the first embodiment described above. A valve 13 is rotatably supported by a bottle 14 for dividing the refrigerant gas flowing from the valve 10 into a suction chamber 24 and a crank chamber 37, and the throttle valve 13 is incorporated into a part of the discharge chamber 25. The bellows 16 rotates via the interlocking ring 18 due to the expansion and contraction movement of the bellows 16.

Further, in a part of the suction passage 7, there is a notched recess 38 that allows the refrigerant gas flowing in from the suction hole 10 to be introduced into the crank chamber 37 in an amount necessary for lubrication when the valve 13 is in the position shown by the solid line in FIG. The refrigerant gas that has passed through the cutout recess 38 flows into the crank chamber 37 through a through hole 39 provided in the valve plate 22 and a vertical hole 40 provided in the cylinder block 1, and the refrigerant gas flows into the crank chamber 37 through a through hole 39 provided in the valve plate 22 and a vertical hole 40 provided in the cylinder block 1. Axis 3
5 and the sliding members such as the bearings of the connecting rod 36, and then flows into the suction chamber 24 through another vertical hole 41 provided in the cylinder block 1 and a through hole 42 provided in the valve plate 22. There is.

In the figure, 33 is a discharge port, 34 is a suction port, 43 is a discharge pulp, and 44 is a suction pulp.

In this embodiment, as described above, the bellows is used because the discharge pressure of the refrigerant gas discharged from the cylinder bore 2 to the discharge chamber 25 is high when a specified amount of refrigerant gas is present in the circuit. 16 is contracted and the valve 13 is maintained in the state shown by the solid line in the figure, so that most of the refrigerant gas that has flowed in from the suction hole 10 flows into the suction chamber 24, and the amount necessary for lubrication enters the crank chamber 37. The liquid flows in and lubricates the sliding member within the crank chamber 37.

In addition, at startup or when the amount of refrigerant gas in the circuit is insufficient, the discharge pressure in the discharge chamber 25 decreases compared to the normal state, so the bellows 16 extends and the valve 13 stands up as shown in the diagram. As a result, the passage leading to the suction chamber 24 is closed or narrowed, and the passage leading to the crank chamber 37 is wide open, so that most of the refrigerant gas flowing in from the suction holes 1 and 0 passes through the crank chamber 37 and then passes through the crank chamber 37. Suction chamber 24
As a result, the sliding member in the crank chamber 37 is effectively lubricated and seizure is prevented.

In the first and second embodiments described above, the discharge pressure in the discharge system was used as a means to control the opening and closing operations of the valve 13, but this could be replaced by other means, such as controlling the temperature of the refrigerant gas in the discharge system. Alternatively, the valve 13 can be replaced with a solenoid valve.

Further, in the embodiment, one valve 13 is provided at the branching part between the passage leading to the suction chambers 24F, 24R, and 24 and the passage leading to the swash plate chamber 6 or the crank chamber 37, but a valve is provided in each of both passages. There is no problem.

As detailed above, the present invention is provided with a valve that controls the flow rate of refrigerant gas that is divided into a passage that introduces the refrigerant gas directly into the suction chamber and a passage that introduces the refrigerant gas into the suction chamber after passing through the crank chamber. This allows most of the refrigerant gas to be directly introduced into the suction chamber during normal operation, while a portion of the refrigerant gas required for lubrication can be introduced into the crank chamber, reducing the resistance to suction of refrigerant gas into the cylinder bore. It is possible to prevent excessive lubrication of the lubricating members in the crank chamber with a small amount of lubrication, and there is no risk of performance deterioration.In addition, when the amount of refrigerant gas sealed in the crank chamber is insufficient at startup or in the circuit, most of the refrigerant gas is pumped into the crank chamber. Since it can be introduced, the sliding member is effectively lubricated to prevent burning, and as a result, the life of the sliding member is extended.

[Brief explanation of drawings]

1 to 4 show a first embodiment of the present invention,
Fig. 1 is a side sectional view of the swash plate compressor, Fig. 2 is a side sectional view with a different cut plane, Fig. 3 is a sectional view taken along line A-A in Fig. 1, and Fig. 4 is a plane showing the valve. 5 and 6 show a second embodiment, FIG. 5 is a side sectional view of the crank type compressor, and FIG. 6 is a plan sectional view. 6...Swash plate chamber, 7...Suction passage, 10
...Suction hole, 13...Valve, 16...
...Be D-24F. 24R, 24... Suction chamber, 27... Radial bearing 28... Thrust bearing, 30...
... Shoe 31 ... Ball, 37 ...
...Crank chamber.

Claims (1)

[Claims] 1. A first passage that introduces refrigerant gas flowing from the suction hole into the suction chamber, a second passage that introduces the refrigerant gas into the suction chamber after passing through the crank chamber, and a first passage in the vicinity of the suction hole. and a valve for controlling the division of the suction refrigerant gas, which is provided at a branch part between the passage and the second passage, and the valve controls the opening degree of the first passage when the discharge refrigerant gas pressure falls below a normal value. A compressor, characterized in that the compressor is operated by a biasing means balanced with the discharge refrigerant gas pressure so as to close or reduce the refrigerant gas pressure.