JPS5944516B2 - rotary compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vane-type rotary compressor used in automobile air conditioners, etc., and includes a highly reliable valve mechanism that opens a lubricating oil supply passage when the compressor is rotating and closes it when the compressor is stopped. One of the purposes is to ensure a sufficient supply of lubricating oil during operation, to prevent lubricating oil from flowing into the cylinder when stopped, to prevent oil compression when restarted, and to prevent reverse rotation immediately after stopping. It is something to do.

Conventionally, in this type of rotary compressor, in order to reliably press the vanes against the inner wall of the cylinder, high pressure generated on the discharge side is used to pressurize lubricating oil and supply it to the bottom of the vane groove, as well as on both end surfaces of the rotor. , a method was used to lubricate the sliding surfaces of the vanes and rotor.

Therefore, once the compressor stops, a portion of the lubricating oil continues to flow to the bottom of the vane groove due to the high pressure remaining on the discharge side, and excess lubricating oil flows into the cylinder through the gap between the rotor end face and side plate, and between the vane and the vane groove. However, as the oil moves further toward the lower pressure side, the rotor rotates in the opposite direction, and the leaked oil is also sent to the suction pipe side.

Therefore, abnormally high pressure caused by oil compression during restarting may cause fatal troubles such as damage to vanes and rotors and deformation of discharge valves.

As a means to eliminate the above drawbacks, we focused on the pressure difference before and after the discharge valve, where there is a significant pressure difference between when the compressor is rotating and when it is stopped, and installed an on-off valve that operates based on this pressure difference in the lubricating oil path. There is a method in which the oil passage is opened when the compressor is rotating, and closed when it is stopped, and this method has achieved some results.
In the case of a vane-type rotary compressor, there is a difference in the gas pressure in the compression chamber before and after the vane passes through the gas pressure outlet in the compression chamber during one rotation, and pulsation corresponding to the number of vanes occurs. As a result, the pressure difference before and after the discharge valve reverses instantaneously, causing the on-off valve to vibrate or move, sometimes blocking the oil passage, causing vane jumping phenomenon and vane noise due to insufficient supply of lubricating oil to the bottom of the vane groove. This caused the occurrence of

The present invention provides a narrow passage in the middle of the gas passage from the gas pressure outlet in the compression chamber to the on-off valve in order to extremely effectively dampen the pulsation with a simple means and ensure the operation of the on-off valve. It is something that

As a configuration for this purpose, the present invention provides a rotary compressor main body that includes at least a cylinder and a rotor that forms a compression chamber for refrigerant disposed in the cylinder, and that is provided so as to be able to freely appear and retract from the rotor and together with the rotor. a vane that forms the compression chamber; a lubricating oil supply passage that pressurizes lubricating oil by the discharge pressure of the cylinder to move the vane in and out;
A valve mechanism is provided for opening and closing the lubricating oil supply passage by using a pressure difference between the compressed gas pressure in the compression chamber and the discharge gas pressure after passing through the discharge valve, and the valve mechanism is connected to a rotary compressor main body. The valve mechanism installed on the side plate consists of a plunger hole, a plunger slidably inserted into the plunger hole, a spherical valve that opens and closes by reciprocating the plunger, and a plunger hole. A narrow passage with a small cross-sectional area is provided in a part of the pressure passage through which the compressed gas pressure is introduced into the valve mechanism, and this narrow passage is connected to the stopper or the plunger hole. or a spiral groove located on the outer periphery of a throttle member provided in the pressure passage.

Hereinafter, the present invention will be described with reference to the accompanying drawings showing one embodiment thereof.

In the figure, 1 is the rotor, 2 is the cylinder, 3 is the front wall,
4 is the rear wall, 5 is the vane, 6 is the refrigerant inlet provided in the cylinder 2, 7 is the discharge port, 8 is the discharge valve, 9 is the cylinder head, 10 is the oil separation chamber, and 11 is the refrigerant from the oil separation chamber 10. The outlet, 12 is a ball bearing, and 13 is a shaft sealing device, thereby forming a well-known basic structure (rotary compressor main body) A of a vane type rotary compressor.

That is, a driving source such as an automobile engine is connected to the shaft groove 1a of the rotor 1, and the rotor 1 is operated.

15 is a circumferential groove that supplies high-pressure lubricating oil 16 to the bottom of the vane groove 14; 28 is a first oil passage that supplies lubricating oil 16 to the shaft sealing device 13 through a second oil passage 29 provided in the rotor 1; It is provided on the rear side wall 4 as shown in FIG.

Reference numeral 17 denotes an outlet for the pressure in front of the discharge valve, which is provided on the rear side wall 4.

Reference numeral 18 denotes a pressure passage that transmits the pressure of the outlet 17 to a plunger on-off valve mechanism to be described later, and 19 is a third oil passage that conveys lubricating oil 16 to the circumferential groove 15, which is located downstream of the plunger on-off valve mechanism to be described later. are doing.

Reference numeral 20 denotes a fourth oil passage that sends the lubricating oil in the oil separation chamber 10 to the plunger on-off valve mechanism, and is located upstream of the plunger on-off valve mechanism, which will be described later. It opens below the oil level.

Next, the plunger opening/closing valve mechanism will be explained.

21 is a plunger hole, and 22 is a protrusion 22a on the top thereof.
The plunger 23 is a fifth oil passage that connects the third oil passage 19 and the fourth oil passage 20, and surrounds the protrusion of the plunger 22, and the lower end of the fifth oil passage 23 is located upstream of the fifth oil passage 23. A passage 31 having a conical shape is formed, into which a steel ball 25 of a size that can block the fifth oil passage 23 is inserted in a loose state, and by vertical movement of the plunger 22, the steel ball 25 is inserted.
5 opens and closes the fifth oil passage 23.

Reference numeral 30 denotes a plug bolt having a male thread that is tightened and fixed to close one end of the plunger hole 21, and one end of the pressure passage 18 opens into the female threaded portion of the plug bolt 30.

Here, since the screwing state of the plug bolt 30 and the rear wall 4 is set to have the function of a fine passage B that communicates the pressure passage 18 and the plunger hole 21, it is not sufficient to ensure airtightness. A gasket 32 is interposed between the two for final sealing.

In the above configuration, when the rotor 1 starts rotating in the direction of the arrow shown in FIG. 2, refrigerant gas containing refrigerating machine oil is sucked in from the refrigerant suction port 6, is compressed by the rotation of the vanes 5 and the rotor 1, and reaches the discharge lower. , the discharge valve 8 is pushed open, and the oil is sent to the oil separation chamber 10.

Here, the refrigerating machine oil is separated from the refrigerant gas due to the difference in specific gravity, and is stored at the bottom as lubricating oil 16.

Meanwhile, the refrigerant gas is sent through the refrigerant outlet 11 into a well-known refrigeration cycle (not shown).

In the flow of refrigerant gas as described above, when focusing on the pressure across the discharge valve 8, the pressure before the discharge valve 8, that is, the pressure generated in the compression chamber 33, the pressure passage 18, and the plunger hole 21, There is a pressure difference between the pressure after passing the discharge valve 8 and the pressure that can at least push the discharge valve 8 open, and the pressure before the discharge valve 8 is high.

In other words, the pressure in the fifth oil passage 23 communicating with the oil separation chamber 10 with the plunger 22 as a boundary and the pressure on the plunger hole 21 side communicating with the pressure passage 18 are the same as the pressure on the plunger hole 21 side communicating with the pressure passage 18.
The sides are high.

This differential pressure is normally generated by pulsating pressure changes that occur in the compression chamber in accordance with the number of vanes 5 used during one rotation of the rotor 1, but this pulsating differential pressure is caused by the above-mentioned stopper bolt 30. Due to the screwed state with the rear side wall 4, the compression chamber 3
3. The pressure is attenuated through a fine passage B provided between the pressure passage 18 and the plunger hole 21, and is transmitted to the plunger hole 21.

Therefore, the plunger 22 smoothly moves upward, and the steel ball 25 is pushed up at the tip of the protrusion 22a of the plunger 22, and the oil separation chamber 10, the fifth oil passage 23, the third oil passage 19,
The high-pressure lubricating oil 16 communicates with the first oil passage 28 and passes through the bottom of the vane groove 14 or the second oil passage 29 to the shaft sealing device 13.
and is supplied to the ball bearing 12.

Next, the operation when the compressor is stopped will be explained.

When the power transmission to the compressor body A is cut off, the discharge valve 8 is immediately closed.

As a result, since the pressure on the refrigerant outlet 11 side is connected to the high pressure side of the refrigerant cycle as is well known, the oil separation chamber 10
The same pressure will be applied.

The pressure on the refrigerant outlet 11 side is controlled by a pressure reducer (not shown).
The pressure in the discharge lower is reduced quickly to balance the low pressure side of the refrigeration cycle, but the speed at which the pressure is balanced is slow.

In other words, the compressed gas in the compression chamber is distributed between the rotor 1 and the front wall 3 and the rear wall 4, between the vane 5 and the inner wall of the cylinder, or between the vane 1 and the front and rear walls 3 and 4, and between the top of the rotor 1 and the inner wall of the cylinder. It tries to leak through the gap to the low pressure side of the compressor.

Therefore, the pressure on the plunger hole 21 side is reduced to the pressure passage 18.
The pressure drops below the pressure on the fourth oil passage 20 and fifth oil passage 23 sides.

Therefore, the force applied to both end surfaces of the plunger 22 is in the opposite direction to that during rotation of the compressor, and the plunger 22 moves downward in the figure, causing the steel balls 25 to move between the fourth oil passage 20 and the fifth oil passage 20.
3 to prevent the lubricating oil 16 pressurized by the residual discharge pressure in the oil separation chamber 10 from flowing into the bottom of the vane groove 14 and into the cylinder.

As time passes, this residual pressure on the high pressure side is balanced through an expansion valve (not shown) installed in the evaporator (not shown), etc. that constitute the aforementioned refrigeration cycle, and finally, the residual pressure in the cylinder 2 is balanced. The pressure inside the suction port 6 and the pressure inside the oil separation chamber 10 are made equal.

Therefore, the pulsating pressure generated in the compression chamber depending on the number of rotations of the rotor 1 and the number of vanes 5 used is transmitted to the valve mechanism through the narrow passage B with the pulsation attenuated, and the compressed gas near the valve mechanism is Due to the passage B, even when the pressure of the compressed gas drops immediately after the vane 5 passes through the outlet 17 of the pressure in front of the discharge valve 8, it is difficult to reduce the backflow toward the above-mentioned outlet 17, and furthermore, the lubricating oil is supplied when the compressor rotates. Since the opening degree of the valve mechanism that keeps the passage 18 open does not change, lubricating oil is continuously supplied to the vane groove 14 and other sliding parts, thereby preventing the vane jumping phenomenon and vane noise.

In addition, since the narrow passage B has an extremely small cross-sectional area and is desirable to have a long overall length, normal machining methods (for example, drilling, electric discharge machining, etc.) have short tool life and high production costs. According to this embodiment, the narrow passage is provided by the screwing state between the plunger hole 21 and the plug bolt 30 that closes it, so the production cost is low.
In addition, since the cross-sectional area of the passage is extremely small and the passage has a helical shape, the overall length can be increased.
This makes it ideal as a passage for pulsation damping.

In this embodiment, the narrow passage B is formed by a minute gap formed when the male threaded part of the plug bolt 30 is screwed into the female threaded part of the plunger hole 21, as shown in FIG.
As shown in FIG. 6, a spiral groove a (thread) is formed in either one of the plug bolts 30 in which the plunger hole 21 is inserted, and the plug bolt 30 is press-fitted into the plunger hole 21 to form a narrow passage B. Alternatively, as shown in FIGS. 4 and 5, one end of the pressure passage 18 is opened in the plunger hole 21,
A narrow passage B is formed by screwing the throttle member 34, which has a spiral groove a formed on the outer periphery of the pressure passage 18, into a threaded groove formed in the pressure passage 18, similar to the above-described embodiment. As shown in Figure 7, the pressure passage 18 or the restricting member 34
Similar effects can also be expected with a configuration in which a spiral groove a is provided in either one of the two to form the narrow passage B.

As is clear from the above embodiments, the rotary compressor of the present invention includes a rotary compressor main body that includes at least a cylinder and a rotor that is disposed within the cylinder and forms a compression chamber for refrigerant. A vane that is provided so as to be freely protrusive and retractable and forms the compression chamber together with the rotor, a lubricating oil supply passage that pressurizes lubricating oil by the discharge pressure of the cylinder to cause the vane to protrude and retract, and compressed gas pressure and discharge in the compression chamber. A valve mechanism is provided for opening and closing the lubricating oil supply passage using the pressure difference between the pressure of the discharged gas after passing through the valve, and a part of the pressure passage for introducing the compressed gas pressure into the valve mechanism is disconnected. A narrow passage with a small area is provided.The narrow passage transmits the pulsating pressure generated in the compression chamber to the valve mechanism in an attenuated state depending on the rotation speed of the rotor and the number of vanes used, and also reduces the compression in the pressure passage. In order to alleviate gas backflow, the valve mechanism is always opened at a constant opening when the compressor is operating, allowing the lubricating oil to flow smoothly and continuously through the lubricating oil supply passage. This suppresses the phenomenon of vanes and supplies lubricating oil to each sliding part, so it is possible to suppress the vane jumping phenomenon and the generation of vane noise as much as possible.

In addition, by making the narrow passage a spiral groove provided in at least one of the stopper or the hole, or a spiral groove located on the outer periphery of the restricting member or the restricting member provided in the pressure passage, a narrow passage with high passage resistance can be created. Moreover, since it is surface processing, it has various advantages such as being cheaper to produce and easier to process than drilling, electric discharge machining, etc., which have short tool life.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a rotary compressor according to an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view taken along line X-X in FIG. 1, and FIG.
The figures are an enlarged sectional view of the main part of Fig. 1, Fig. 4 is an enlarged sectional view of the main part of another embodiment of the present invention, Fig. 5 is an enlarged sectional view of the main part of Fig. 4, and Figs. Each figure is an enlarged sectional view of a narrow passage portion showing other embodiments of the present invention. 1...7-ta, 2...cylinder, 5...
... Vane, 16 ... Lubricating oil, 18 ...
...Pressure passage, 19,20°23.28,29...
...Oil passage (lubricating oil supply passage), 21...Plunger hole, 25...Steel ball, 30...
Plug bolt (plug body)', 34... Throttle member, A.
...Compressor body, a...Spiral groove, B.
...Narrow passage.

Claims (1)

[Claims] 1. A rotary compressor body equipped with a cylinder having a refrigerant suction port and a rotor disposed within the cylinder that forms a compression chamber for refrigerant, the rotary compressor body being provided so as to be able to appear and retract from the rotor and to form the compression chamber together with the rotor. a vane to be formed; an oil separation chamber on which the discharge pressure of the cylinder acts; a lubricating oil supply passage that pressurizes lubricating oil by the discharge pressure to cause the vane to move in and out; compressed gas pressure in the compression chamber and a discharge valve. A valve mechanism is installed in which a valve mechanism is provided for opening and closing the lubricating oil supply passage by using a pressure difference between the discharge gas pressure after passing through the passage, and the valve mechanism is further provided on a side plate constituting the main body of the rotary compressor. The plunger is configured to include a plunger hole, a plunger slidably inserted into the plunger hole, a spherical valve that opens and closes by reciprocating the plunger, and a stopper that closes the plunger hole. A narrow passage having a small cross-sectional area is provided in a part of the pressure passage through which compressed gas pressure is introduced into the valve mechanism, and the narrow passage is formed in a spiral groove in at least one of the plug body or the plunger hole. Alternatively, a spiral groove is formed on the outer periphery of a throttle member provided in the pressure passage, a refrigerant outlet is provided in the oil separation chamber, and a refrigeration cycle is connected between the refrigerant inlet and the refrigerant outlet to form a closed circuit. Rotary compressor.