JPH0514573U - Air conditioner presser - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an air compressor capable of supercharging air into a cylinder chamber without providing a supercharger. In an air compressor of a displacement type in which a piston reciprocates in a cylinder chamber and having an oil-free structure, an air inlet 30 and an air outlet 35 are arranged in a crank chamber 25, and an air inlet 30 is provided. Is provided with a sub intake valve 31 that opens during the upward stroke of the piston 14 and closes during the downward stroke of the piston 14, and a communication pipe 36 is disposed at the air discharge port 35.
It is connected to the.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an air compressor, and more particularly, to a technology for improving intake characteristics, and more particularly, to an air compressor effectively used for a brake device of a large vehicle such as a bus or a truck.

[0002]

[Prior Art]

 Generally, compressed air (hereinafter referred to as air) is used as a working energy source in a braking device for a large vehicle such as a bus or a truck. Then, in order to obtain this air, an air compressor is connected to the engine in the brake system of a large vehicle, and the force generated by the air compressor is supplied to the air brake system or the air over hydraulic brake system. Therefore, the wheel brakes are activated.

[0003]

[Problems to be solved by the device]

 In such an air compressor, the suction valve that opens and closes the suction passage that communicates with the cylinder chamber is configured to open and close by the set load of the spring and the differential pressure before and after the suction valve. The filling efficiency of air is about 40 to 50%, and it is difficult to increase the filling efficiency during inhalation.

Therefore, a method of utilizing a supercharger arranged in the middle of the intake passage of the engine and introducing air supercharged by the supercharger into the cylinder chamber of the air compressor as the engine is driven. The system which adopted is proposed. However, in such a system, since a supercharger must be provided in addition to the air compressor, the device becomes large and it is difficult to reduce the size and weight of the device.

The present invention focuses on an oil-free air compressor and realizes supercharging of air by pressurizing the air in the crank chamber of an oil-free air conditioner pressurizer. (EN) An air compressor capable of supplying supercharged air into a cylinder chamber without providing a feeder.

[0006]

[Means for Solving the Problems]

 The air compressor according to the present invention includes a cylinder chamber, a piston that is reciprocally fitted in the cylinder chamber, a crankshaft that is rotationally driven by a drive device, and a crankshaft that is slidably contacted with the crankshaft. A connecting rod that is connected to the piston and converts the rotational movement of the crankshaft into reciprocating motion and transmits it to the piston; an intake valve that opens and closes the intake passage that communicates with the cylinder chamber; and a communication with the cylinder chamber. In the air compressor having a discharge valve for opening and closing the discharge passage, the crank chamber in which the crankshaft is installed has an inlet for introducing air and an outlet for discharging air. In addition, a sub-suction valve that opens when the piston rises and closes when the piston descends is installed in the inlet. A communication pipe is provided at the discharge port, and the communication pipe is connected to the suction passage.

[0007]

[Action]

 According to the above-mentioned means, the intake air is introduced into the crank chamber from the sub intake valve during the upward stroke of the piston, and the sub intake valve is closed during the downward stroke of the piston to increase the air pressure in the crank chamber. This air is sent to the suction passage through the communication pipe, and when the suction valve opens due to the balance between the pressure in the cylinder chamber and the pressure of the air in the communication pipe, the air introduced into the communication pipe is introduced into the cylinder chamber. Since this air is actually supercharged in the crank chamber, it is possible to supply supercharged air to the cylinder chamber without using a supercharger, improving the charging efficiency during suction. be able to.

[0008]

【Example】

 FIG. 1 is a vertical sectional view showing an oil-free type air compressor which is an embodiment of the present invention.

In the present embodiment, the air compressor 11 according to the present invention is of a positive displacement type in which a piston reciprocates and has an oil-free structure, and includes a cylinder body 12. A cylinder chamber 13 is formed in the main body 12, and a piston 14 is reciprocally slidably fitted in the cylinder chamber 13. The piston 14 is configured to be linearly driven by a crankshaft, which will be described later, via a connecting rod. A cylinder head 15 is fixed in contact with one end (hereinafter, referred to as an upper end side) of the cylinder chamber 13 so that a discharge port and a suction port of the cylinder head 15 communicate with the cylinder chamber 13, respectively. It has been opened. A discharge passage 17 is connected to the discharge port 16, and a discharge valve 18 is provided between the discharge outlet 16 and the discharge passage 17 inside the cylinder head 15 so as to open and close the flow. The discharge valve 18 is configured to close the discharge port 16 by the biasing force of the spring 19 and open the discharge port 16 against the biasing force of the spring 19 when the pressure of the air in the cylinder chamber 13 rises. There is. The discharge passage 17 is connected to a reservoir or the like (not shown) via a check valve.

On the other hand, a suction passage 21 is connected to the suction port 20, and a suction valve 22 is arranged inside the cylinder head 15 between the suction port 20 and the suction passage 21 to connect the flow passage. It has been opened and closed. The suction valve 22 is configured to close the suction port 20 by the biasing force of the spring 23 and open the suction port 20 when the air in the suction passage 21 becomes higher than the air in the cylinder chamber 13. ing.

A crank case 24 is continuously provided below the cylinder body 12, and a crank chamber 25 communicating with the cylinder chamber 13 is formed in the crank case 24. A crankshaft 26 driven by an engine is installed in the crank chamber 25 so as to traverse the crankshaft 26. The crankshaft 26 is rotatably supported by a crankcase 24. A lower end of a connecting rod 28 is rotatably supported on the crankshaft 26, and the piston 14 is rotatably connected to an upper end of the connecting rod 28 via a pin 27. In the above structure, each sliding surface of the reciprocating motion adopts an oil-free structure by appropriate means such as surface treatment and conversion of the piston ring to synthetic resin or ceramics. The oil-free structure is adopted by suitable means such as oil-free bearing structure and shield type bearing structure.

An inlet port 30 communicating with an intake passage (not shown) of the engine is arranged on the wall surface of the crankcase 24 at an upper position and is opened so as to communicate with the crank chamber 25. A sub intake valve 31 is provided at the inlet 30. The sub intake valve 31 includes a reed valve 32 and a back plate 33, and the ends of the reed valve 32 and the back plate 33 are fixed to the wall surface of the crank chamber 25 by bolts 34. The sub intake valve 31 bends the reed valve 32 toward the back plate 33 side in response to the differential pressure between the intake pressure in the intake passage of the engine and the intake pressure in the crank chamber 25, so that the piston 14 rises. The valve is opened during the stroke, and is closed by returning the reed valve 32 during the downward stroke of the piston 14.

On the other hand, at another portion of the upper portion of the wall surface of the crankcase 24, an exhaust port 35 for discharging the air sucked into the crank chamber 25 is opened. A communication pipe 36 for guiding the air sucked into the crank chamber 25 to the suction passage 21 is connected to the discharge port 35, and the other end of the communication pipe 36 is connected to the suction passage 21 opened in the cylinder head 15. Has been done.

Next, the operation will be described. When the crankshaft 26 is rotationally driven by the engine, the piston 14 reciprocates in the cylinder chamber 13. When the piston 14 reciprocates and the piston 14 moves up and shifts to the compression stroke, the air in the cylinder chamber 13 is pressurized, and the pressurized air is discharged to the discharge passage 17 side through the discharge port 16. Is discharged. At this time, the internal pressure of the crank chamber 25 decreases, so the inlet 30 is opened by the sub intake valve 31, and the intake air from the intake system of the engine is introduced into the crank chamber 25.

Next, when the piston 14 descends and shifts to the intake stroke, the internal pressure in the crank chamber 25 rises, the sub intake valve 31 closes, and the inlet 30 is closed. When the piston 14 further descends in this state, the internal pressure in the crank chamber 25 further increases as the piston 14 descends, and the air pressurized in the crank chamber 25 passes through the communication pipe 36 to the suction passage 21 side. Sent to.

When the pressure of the air in the suction passage 21 becomes higher than the pressure of the air in the cylinder chamber 13, the suction valve 21 opens and the air in the communication pipe 35 is introduced into the cylinder chamber 13. It At this time, the air introduced into the cylinder chamber 13 is pre-pressurized air in the crank chamber 25, and the supercharged air is introduced into the cylinder chamber 13.

When the piston 14 rises again and shifts to the compression stroke, the supercharged air is further pressurized in the cylinder chamber 13 and then discharged to the discharge passage 17 side.

As described above, according to this embodiment, the air compressed in the crank chamber 25 in advance is supercharged from the communication pipe 36 to the suction passage 25. The filling efficiency at the time of inhalation can be improved without providing the device, and the device can be made compact and lightweight.

Incidentally, when the conventional air compressor and the air compressor according to the present embodiment are measured and compared with respect to the compression efficiency, the compressor according to the present embodiment is 1.3 times that of the conventional air compressor. It was confirmed that

In this embodiment, since the air compressed in the crank chamber 25 is supercharged into the cylinder chamber 13, it is desirable to apply it to an oil-free type air compressor. Generally, in air brake devices, rubber parts are often used in each device, and the inclusion of oil in the air impairs the function of each device.Therefore, extreme care must be taken when removing oil from the air. Has been done. In an oil-lubricated air compressor in which oil accumulates in the crank chamber, overpressurizing the air in the crank chamber and supercharging it in the cylinder chamber will mix the oil into the air, so it must be avoided. .. Therefore, the present invention can be applied only to an oil-free type air compressor in a pneumatic system such as an air brake device in which it is necessary to avoid mixing of oil in air.

[0021]

[Effect of the device]

 As described above, according to the present invention, the air is introduced into the crank chamber during the compression stroke of the piston, and the air in the crank chamber is compressed during the intake stroke of the piston to supercharge the cylinder chamber. Therefore, the compression efficiency can be improved without providing a supercharger, the compression efficiency can be improved, and the size and weight of the device can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an oil-free type air compressor according to an embodiment of the present invention.

[Explanation of symbols]

11 ... Air compressor, 12 ... Cylinder body, 13 ...
Cylinder chamber, 14 ... Piston, 15 ... Cylinder head,
16 ... Discharge port, 17 ... Discharge passage, 18 ... Discharge valve, 19 ... Spring, 20 ... Suction port, 21 ... Suction passage, 22 ... Suction valve, 23 ... Spring, 24 ... Crankcase, 25 ...
Crank chamber, 26 ... Crank shaft, 27 ... Crank pin, 28 ... Connecting rod, 30 ... Inlet port, 3
1 ... Sub intake valve, 32 ... Reed valve, 33 ... Back plate, 34 ... Bolt, 35 ... Discharge port, 36 ... Communication pipe.

Claims (1)

[Scope of utility model registration request] 1. A cylinder chamber, a piston that is reciprocally fitted in the cylinder chamber, a crankshaft that is rotationally driven by a drive unit, and is rotatably connected in sliding contact with the crankshaft, and , A connecting rod that is connected to the piston and converts the rotational movement of the crankshaft into reciprocating motion and transmits it to the piston, an intake valve that opens and closes an intake passage that communicates with the cylinder chamber, and opens and closes a discharge passage that communicates with the cylinder chamber. In an air compressor provided with a discharge valve, an inlet for introducing air and an outlet for discharging air are opened in the crank chamber in which the crankshaft is arranged, and the inlet has the outlet There is a sub-suction valve that opens when the piston rises and closes when the piston descends, and a communication pipe is provided at the discharge port. ,
An air compressor, wherein the communication pipe is connected to the suction passage.