JPS6261796B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an air compressor as a power generation source for air systems such as brakes of large trucks and buses, or construction machinery, which is directly connected to the engine (regardless of the drive ratio), that is, when the engine rotates. As long as the pressure is higher than the high pressure limit required by the air system, the suction valve of the air compressor should be kept open (unloaded) and the compression action should be maintained. This is an automatic operation system that reduces the driving power due to idle rotation that is not performed, and eliminates the above state and performs normal compression action below the low pressure limit required by the air system. Conventionally, the configuration of the above system was , a pressure regulator valve for pressure control was provided separately from the air compressor, and the air compressor had an unloader plunger connected to it via piping. By incorporating the combined mechanism into the air compressor, it is no longer necessary to install the conventional pressure regulator valve, and the joints attached to it are also unnecessary, eliminating the cause of air leakage from that part. The purpose is to improve safety by eliminating the need for brackets and bolts for mounting on a vehicle, thereby realizing simplification and weight reduction of the air system reliably and at low cost.

An example of a conventionally used automatic valve type reciprocating air compressor is shown in FIG. 1. 1 is a suction port, and 2 is a delivery port, from which compressed air is delivered to an air tank 3. A pressure regulator valve 4 is installed between the air tank 3 and the unload port 5.

When the pressure inside the air tank 3 reaches the pressure set as the high pressure limit, the pressure regulator valve 4 operates to send air to the port 5, and the unloader plunger 6 is pushed down, causing its tip 6a to The valve 7 is kept in an unloaded state while being pushed open. Air is consumed and air tank 3
When the internal pressure drops to the pressure set as the low pressure limit, the pressure regulator valve 4 is activated and the air between the port 5 and the valve 4 is discharged from the exhaust port 4a, and the plunger 6 is activated as shown in FIG. The state is restored and the compression action is resumed.

The present invention combines the functions of a pressure regulator valve with the unloader plunger in the conventional method described above.An example of the present invention will be explained below with reference to the drawings. is a suction board, 2 is a delivery port, 3 is an air tank, and 7 is a suction valve. The automatic unloading system of the present invention mainly consists of a valve 8, a piston with legs 9, and a stem 16, and is connected to an air tank 3 through port a and exhausted through port b.

When the pressure in the air tank 3 increases, the valve 8 moves down together with the piston 9 and comes into contact with the exhaust seat 10 located at the bottom of the stem 16. When the pressure increases beyond that level, the annular area defined by the outer diameter of the piston 9 and the feed seat 11 provided on the piston 9 becomes an effective area and maintains that state against the spring 12. When the pressure increases further and reaches the high pressure limit set value, the feed sheet 11 opens and after that, the effective area becomes the entire area of the piston 9, so the piston 9 rapidly descends, and the foot 9 at the tip of the feed sheet 11 opens.
a pushes open the suction valve 7 and enters the unload state. When the pressure in the air tank 3 decreases, the piston 9 moves upward by the spring 12 and closes the feed seat 11. Next, the exhaust seat 10 opens and the air inside the feed seat 11 passes through the exhaust port 13 and is discharged from the rubber etc. The center part 15 of the boot 14 made of elastic material is pushed open and released into the atmosphere from the port b to restore the loaded state. Note that 8a is a contact portion made of an elastic body provided on the seat surface of the valve 8;
17 is a spring attached to the valve 8, and 18 is a spring receiver.

FIG. 3 illustrates the above-mentioned state, where A is the same loaded state as in FIG. 2 and the tank pressure _P1 is low. When the tank pressure increases to _P2 , state B will occur.
When the tank pressure further increases and reaches the high pressure limit set value _P3 , the unload state of C is entered.

The set pressure is adjusted by rotating the stem 16 and changing the position of the exhaust seat 10. The opening of the exhaust port 13 is always closed with an elastic body to prevent dust from entering.

As is clear from the above embodiments, the present invention has a simple configuration, is easy to manufacture and handle, and is capable of reliable automatic operation.The present invention eliminates the pressure regulator valve in the conventional system and eliminates the need for attached piping. , has the advantage of improving safety.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view showing an example of a conventional method, FIG. 2 is a partial cross-sectional view showing an example of the implementation of the present invention, and FIG.
Figures A, B, and C are also partially sectional views for explanatory purposes. The symbols in the drawings indicate the following members, respectively. 1: Suction port, 2: Delivery port, 3: Air tank, 4: Pressure regulator valve, 5: Unload port, 6: Unloader plunger, 7: Suction valve, 8: Valve,
9: Piston with foot, 10: Exhaust seat, 11: Feed seat, 12: Spring,
13: Exhaust port, 14: Boot, 15: Center part, 1
6: Stem, 17: Spring, 18: Spring receiver, a, b: Port.

Claims (1)

[Claims] 1. A piston with a foot is provided on the same axis on the opposite side to the opening direction of the suction valve, and a piston with a foot is provided which receives the pressure of the air tank and pushes the suction valve open at the high pressure limit set value. A valve that contacts the feed seat located at the bottom is slidably fitted onto a stem provided on the main body so that its position can be adjusted freely, and an exhaust seat that contacts the valve is attached to the lower part of the stem, and an exhaust seat that contacts the valve is attached to the lower part of the stem. Each valve is provided with an exhaust port leading from the top to the top, and a spring is attached to each of the valves and the piston with legs. In the loaded state where the air tank pressure is low, the feed seat contacts the valve and the high pressure limit set value is reached in the unloaded state. An air compressor with an automatic unloading system, characterized by the fact that the feed seat is moved away from the valve. 2 A two-stage recess is formed at the top of the footed piston, the feed seat is formed at the intermediate stage, and the exhaust part of the stem is accommodated in the lower recess, and the valve is arranged on the same contact surface. An air compressor with an automatic unloading system according to claim 1, wherein the air compressor is adapted to be able to come into contact with both seat portions. 3. A boot made of an elastic material such as rubber is provided to cover the upper end exposed from the main body of the stem, and the opening of the stem is normally closed by the boot, and the boot is pushed up to exhaust air only during exhaust operation. An air compressor with an automatic unloading system according to claim 1.