SU1370292A2 - Pressure valve of high-pressure fuel-injection pump - Google Patents

Abstract

The invention relates to engine building and allows for improved economy by improving fuel delivery performance. The locking element 8 is provided with a protrusion 14 entering the axial hole 7 of the housing 1 and forming a throttling gap 15 to resist the passage of fluid through the axial hole 7 of the housing 1 when the element 8 is moved between the seating position on the saddle 6 and the opening position of the radial holes 4 of the housing. At the beginning of the pump plunger stroke, the gap 15 creates resistance to the passage of fluid in the cavity between the seat 6 and the element 8. This provides an additional slowing down of the movement of the element 8 as it moves away from the saddle. After the inlet of the pumping chamber is blocked by the plunger, the protrusion 14 completely comes out of the hole 7 and the resistance element 8 due to an increase in the depth of the annular groove 12. Element 8 abruptly moves and completely opens hole 4. After the plunger supplies fuel, the protrusion 14 enters the holes 7 of the casing 1 with a throttling gap 15, creating resistance to the passage of fluid from the spool member. Resistance to the passage of fluid dampens the impact when landing element 8 on the saddle. 1 il. 5 cl with vj о N9 Ю 14)

Description

FIELD OF THE INVENTION The invention relates to mechanical engineering, engine building, namely, fuel-injection equipment of multi-cylinder diesel engines.

The purpose of the invention is to improve efficiency by improving fuel delivery performance.

The drawing shows the valve, a longitudinal section.

The injection valve contains a cylindrical body 1, which is located in the cavity of the fuel union of a high pressure diesel injection pump of a diesel engine (not shown). The housing 1 has an axial chamber 2, which communicates with the cavity of the nozzle (not shown) by means of the connecting channel 3 and the radial openings A for the passage of fuel to the engine nozzle. The housing 1 from the end facing the discharge pipeline (not shown) is provided with a bottom 5, and from the other end, on the side of the pre-plunger volume (not shown) has an internal conical seat 6 with an axial bore 7. In the axial chamber 2 axial movement of the spool locking element 8, having a lateral sealing surface 9, mating with the inner surface of the chamber 2 of the housing 1, and an end sealing surface 10 mating with the seat 6. In the chamber 2 a compression spring 11 is installed, pressing the locking element 8 to the saddle 6.

The valve is also provided with a throttle device for changing the flow area of the connecting channel 3 with axial movement of the locking element 8. The throttle device is made in the form of an annular groove 12 on the outer surface of the locking element and an additional channel 13 in the latter, the annular groove 12 has a variable cross-section along the longitudinal axis and is constantly communicated with the connecting channel 3 and the axial chamber 2 through the additional channel 13.

The locking element 8 is provided with a protrusion 14 entering the axial hole 7 of the housing 1, forming a throttling opening of the radial holes 4 of the core 1.

Discharge valve working

g as follows.

In the initial position, the spool valve 8 by the spring 11 is pressed with its end sealing surface 10 to the saddle 6 of the building

10 ca 1 and the lateral sealing surface 9 closes the radial holes 4 of the housing 1 and maintains the residual pressure in the nozzle cavity and the discharge pipe (not

1G kazano). At the beginning of the stroke of the pump plunger, even before the inlet opening in the pump chamber is closed, the pressure in the above plunger volume begins to increase. It acts on the ledge

20 locking element 8,

The throttle device resists the exit of fuel from chamber 2 and inhibits movement beyond the porous element 8. Therefore,

A solid pipeline receives a small amount of fuel. A throttling lock 15 creates resistance to the passage of fluid into the cavity between the 6 nd of body 1 and the locking element.

30 8, which provides additional slowing down of the movement of the locking element 8 when moving away from the saddle 6.

After the pump plunger closes the pump inlet

.jg of the chamber, the pressure in the pre-plunger volume increases sharply and the locking element 8 moves a predetermined distance from the seat 6, this starts the opening of the radial openings 4 to allow fuel to pass from the plunger volume to the discharge pipeline. At the same time, the protrusion 14 of the locking element 8 completely exits the axial bore 7 of the housing

45 1. The resistance to movement of the locking element 8 is reduced due to an increase in the depth of the annular groove 12.

50 The locking element 8 moves abruptly and fully opens the opening 4. After the end of the supply of fuel to the pump plunger, the pressure in the above plunger volume drops. Shut-off

15 to create a resistance element 55 under the action of a spring 11

open the radial holes 4 of the housing 1.

Discharge valve working

in the following way.

In the initial position, the spool locking element 8 is pressed by the spring 11 with its end sealing surface 10 against the seat 6 of the housing 1, and overlaps the radial holes 4 of the housing 1 with the lateral sealing surface 9 and maintains the residual pressure in the nozzle cavity and the discharge pipe (not shown). At the beginning of the stroke of the pump plunger, even before the inlet opening in the pump chamber is closed, the pressure in the above plunger volume begins to increase. It acts on the ledge

the locking element 8,

The throttle device resists the exit of fuel from the chamber 2 and inhibits the movement of the locking element 8. Therefore, a small amount of fuel enters the discharge pipe. Throttling lock 15 creates resistance to the passage of fluid into the cavity between the saddle 6 of the housing 1 and the locking element

8, which provides additional slowing down of the movement of the locking element 8 when moving away from the seat 6.

After the pump plunger closes the inlet of the pump chamber, the pressure in the supra-plunger volume increases dramatically and the locking element 8 moves a predetermined distance from the seat 6. This starts the opening of the radial holes 4 for the passage of fuel from the supra-plunger volume to the discharge pipeline. At the same time the protrusion 14 of the locking element 8 completely out of the axial hole 7 of the housing

1. The resistance to movement of the locking member 8 is reduced due to an increase in the depth of the annular groove 12.

The locking element 8 moves abruptly and opens the opening 4 completely. After the pumping fuel supply is terminated, the pressure in the above plunger volume drops. Shut-off

nor the passage of fluid through the axial hole 7 of the housing 1 when moving the locking element 8 between the position of its landing on the seat 6 and the position

returns to the starting position. When this cylindrical protrusion 14 of the locking element 8 enters the hole 7 of the housing 1 with a throttling

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Claims (1)

a gap 15 which creates resistance to the formula of the invention for the passage of fluid from under the spool-supercharger valve of the fuel-injected element 8. Resistance to the passage of an overflow pump for a high fluid pressure, which increases with appr. St. If 1288334, about t of l and h of the locking element 8 to the saddle with the fact that, in order to increase 6, it absorbs the blow when the locking valve is fitted by the economy by improving the element 8 on the saddle 6. The spool locking element is equipped with such a method offered by a valve placed in the axial bore of the pan to improve the character of the housing with the formation of a throttling fuel injecting gap.