SU479877A1 - Lubrication system for carburetor internal combustion engine - Google Patents

Description

The invention relates to mechanical engineering and is intended for the lubrication of small carbureted internal combustion engines.

Lubrication systems for internal combustion engine carburetor engines are known, which contain a worm pump for the delivery of oil from the tank to the metering device, the output channel of which communicates with the engine cavity through a discharge valve.

However, the use of conventional injection valves with rigid shut-off elements in known lubrication systems disrupts the stability of the system with a continuous supply of oil if the oil is introduced into the cavities of the engine in which variable suction levels occur, such as, for example, in the throttle body of the engine intake duct. The reason for this is that, in valves of the type mentioned, the power device that loads the locking element is exposed to the negative pressure that occurs in the engine cavity, which leads to an unregulated oil leaking from the system into the cavity.

The purpose of the described invention is to eliminate this drawback and to improve the accuracy of oil flow control.

This is achieved by the fact that the dispenser outlet channel is provided with an overlapped spring-loaded diaphragm installed in the discharge valve.

The drawing shows the scheme of the described system.

The lubrication system contains a tank connected by pipe 2 to a pump 3 of a screw-type. A cylindrical hole 5 is made in the pump casing 4 to accommodate a screw 6 in it. The side surface of the hole 5 is smooth. The screw has one screw groove 7 on the surface, i.e. it is made single-threaded. The screw shaft 8 extends beyond housing 4. The shaft 8 directly connects the screw to 6 with the crankshaft 9 of the engine.

10, an internal combustion that simultaneously drives the pump 3.

In the housing 4 of the pump 3 is made of two channels 11 and 12.

Channel II sends oil to pump 3

from the tank I, and the channel 12 serves to exit the oil under pressure and supply it to the metering device 13. The latter is housed in the housing with the pump 3 so that the pump outlet 12 serves as the inlet to the metering

devices. In the opening 5 of the housing 4 before the entrance to the channel 12 is installed fnlter 14 for oil.

The metering device 13 is a rod 16 with an external cutting on the side surface located in the opening 15 made in the housing 4. The rod 16 serves as a throttling element, and the screw-cutting on its side surface forms with the walls of the hole 15 a throttling channel for the passage of oil. The channel 12 is located transversely to the axis of the hole 15 so that the fluid flow coming out of it hits the side surface of the throttling element erased 16. The rod 16 is placed in the hole 15 with the possibility of reciprocating movement. For this, it has a smooth portion extending beyond the bounds of the housing 4 through the gland 17 and serving for connecting it to the drive.

The drive of the metering device is a lever mechanism 18 comprising a double-arm lever 19, one end of which is connected by a pull 20 to an end of the stem 16, and the other by a cable 21 with a special coupling 22 placed in slot 23 mounted on the vehicle. The pistol 22 is connected by a cable 24 to the throttle valve 25 of the carburetor 26. On the other hand, the piston 22 is connected by a cable 27 to the throttle valve handle 28, which separates the pipe 29, which serves to suck air into the carburetor, from the throttle space 30 of the carburetor. To return the rod 16 to its original position, corresponding to the idling of the engine, spring 31 is put on its smooth part. Two channels 32 and 33 depart from hole 15. Channel 32 serves to bypass private oil into channel I, and channel 33 to connect to the discharge pipe 34, in which the discharge valve 35 is installed with the spring valve diaphragm 36.

A signaling device is installed on the discharge pipe 34, which includes a pressure sensor 37 and a pointer 38, which signals the pressure in the pipe 34 and the valve 35. The outlet channel of the valve 35 is connected to the pipe 39, which ends with a spray gun 40 inserted into the throttle space 30 of the carburetor 26. Carburetor has a float chamber 41, which is connected by a pipe 42 to the fuel tank 43.

The described lubrication system of the two-stroke carburetor engine works as follows. The oil from the tank 1 flows by gravity to the pipeline 2 to the channel 11 to the screw 6 of the pump 3. The pump is driven by the crankshaft 9 of the engine 10 connected directly to the shank 8 of the screw 6. When the screw 6 is rotated, the oil is fed through the groove 7 to the filter 14, where it is cleaned of mechanical impurities, and through the channel 12 enters the lateral surface of the rod 16. Next, through the screw thread of this rod 16, the oil enters the channels 32 and 33, and the flow of oil is separated in correlation depending on the length of the channels, formed by screw thread with erzhn openings 16 with the surface 15 and located

on both sides of channel 12. Through channel 32, the oil enters channel 11, adjacent to port 5. Through channel 33, oil enters pipe 34 and further to discharge valve 35. In this case, pipe 34 maintains an overpressure throughout the pump. (approximately 0.4 kgf / cm with a minimum flow) required for normal system operation, regardless of the change in the operating mode of the engine 10. The operating mode of the engine 10 is set by turning the handle 28, the movement of which through the cable 27 is transmitted to the vehicle 22, moving in the sleeve 23up or down (

drawing). Further, the movement from the ground 22 is simultaneously transmitted through the cable 24 to the throttle valve 25 of the carburetor 26 and through the cable 21, the lever 19 and 20 to the rod 16 of the metering device 13. In this case, the rod 16 moves along the axis of the hole 15, changing the length of the throttling channels lying on the flow paths of oil from channel 12 to channels 32 and 33, and, consequently, the proportion of flow directed in line 34 to valve 35.

The rod returns to the initial position corresponding to the minimum supply under the action of the spring 31. The excessive pressure of oil in the pipeline 34 actuates the sensor 37 with the indicator 38. This allows you to control the operation of the system.

The oil flow in the valve 35 pushes the diaphragm 36 and enters the channel to which the pipeline 39 adjoins. The oil enters through the pipeline 39 into the sprayer 40 introduced into the throttle space 30 of the carburetor 26. At the same time, the float chamber 41 of the carburetor 26 is fed through the pipeline 42 fuel from tank 43. From float

the chamber 41, the fuel enters the zone of the throttle valve 25 of the carburetor 26, where it is displaced with air sucked through the inlet pipe 29 of the carburetor 26, forming a combustible mixture. The amount of this mixture

entering the engine 10 is regulated by changing the position of the throttle valve 25. In the throttle space, the flow of combustible mixture washes the sprayer 40 and captures the oil droplets with which it enters the engine 10 to the liners and into its cylinders.

The presence of a diaphragm installed in the discharge valve in the system eliminates the possibility of unregulated oil leaks,

significantly clears the possibility of a general layout of the lubrication system, since it does not limit the choice of the place for introducing oil under a given pressure, and allows maintaining the pressure required for

its stable operation, regardless of the pressure in the engine cavity.

Subject invention

The lubrication system of the carburettor internal combustion engine, which contains a worm

a pump for supplying oil from the tank to the dosing unit, the output channel of which is in communication with the engine cavity through the discharge valve, in order to increase

precision control of oil supply, the outlet channel of the dispenser is made overlapped by a spring-loaded diaphragm installed in the valve.

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