SU1288334A1 - Pressure valve of high-pressure fuel injection pump - Google Patents

Abstract

FIELD OF THE INVENTION The invention relates to the field of dvigatelement and makes it possible to improve pump xy-ki. The injection valve is provided with a throttle device for changing the bore for changing the bore of the connecting channel 3 with the axial movement of the locking element (D) 8 The connecting channel 3 can be located both in the bottom 5 of the housing 1 and in its wall. In the first case, the throttle device can be made in the form of a profiled needle 11 connected to the ZE 8, and in the second case, in the form of an annular groove on the outer surface of the EE 8. This embodiment of the injection valve improves the uniformity of fuel injection through the nozzles of different cylinders, which helps reduce fuel consumption during the work of the multi-cylinder-diesel engine. 2 з.п, ф-л, 4 Il. with S (L with IC 00 00 co 00 4: FU2.7

Description

The invention relates to mechanical engineering, more specifically to engine building, namely to a fuel injection apparatus for multi-cylinder diesel engines, and can be used in injection valves of high-pressure fuel injection pumps,

Figure 1 shows the discharge valve, a longitudinal section; figure 2 - node 1 in figure 1; fig.Z - discharge valve with a variant of the throttle device, a general view; figure 4 - node II fig.Z.

The discharge valve consists of a cylindrical body 1, which is located in the cavity of the choke (not shown). The housing 1 has an axial chamber 2 communicating with the nozzle cavity using a connecting channel 3 and radial channels 4 for the passage of fuel to the engine nozzle. The housing 1 from the end facing the injection fuel line (not shown) is provided with a bottom 5, and from the other end The sides of the above plunger volume (not shown) have a saddle 6 with a passage channel 7. In the axial chamber 2, the spool locking element 8 is mounted for axial movement and provided with sealing surfaces on the lateral outer direction; the surface 9 connected to the inner surface of the housing forming the axial chamber 2 and on the end surface to interface with the saddle 6. The locking element 8 is provided with a compression spring 10 located in the axial chamber 2 and pressing the locking element 8 against the seat 6. The valve is provided with a throttle device for changing the flow area of the connecting channel 3 with the axial m moving the locking element 8, the connecting channel 3 can be located in the bottom 5 of the housing 1, then the throttle device is made in the form of a profiled needle 11 connected to the locking element 8 and placed with a gap in the connecting channel 3. The connecting channel 3 can also be located in the wall of the housing 1, then the throttle device is formed in the form of an annular groove 12 on the outer surface of the locking element 8 and the additional channel 13 in the latter, with the annular groove 12

five

0

five

0

five

0

five

0

five

along the longitudinal axis, the cross section and is permanently communicated with the connecting channel 3 and the axial chamber 2 through the additional channel 13.

In the initial position, the spool locking element 8 is pressed by the compression spring 10 with its end sealing surface to the saddle 6 of the housing 1, and the lateral guide surface 9 blocks the radial channels 4. When the locking element 8 moves from the saddle 6 for a given distance, the radial channels 4 for the passage of fuel from the above-plunger volume to the injection fuel line, Igl a 1 1 and the annular groove 12 are profiled in such a way that the throttle device creates the greatest resistance the passage of fuel between the chamber 2 and the axial fitting cavity in the rest position of the locking element 8 and the resistance decreases when the lock member 8 moves away from the seat 6 in the direction of radial channels opening 4. For this purpose the needle 11 and the annular groove 12 having a variable diameter along the length axis.

The valve operates as follows

In the initial position, the valve maintains the residual pressure in the injection fuel line and the nozzle cavity.

During the plunger stroke, before the inlet opening closes, the pressure in the supra-plunger volume begins to increase. This pressure acts on the locking element 8. The throttle device resists .i to the fuel outlet from the axial chamber 2 and inhibits the movement of the locking element 8, therefore a small amount of fuel enters the injection fuel line.

After the pump plunger closes the inlet, the pressure in the pre-plunger volume increases dramatically. Under the action of this pressure, the locking element 8 moves, overcoming the force of the spring 10 and the back pressure in the axial chamber 2. This increases the gap between the needle 11 and the connecting channel 3 or the depth of the annular groove against the connecting channel increases, the resistance created by the throttle device 3 decreases.

The BOM and the shut-off element quickly moves to the position at which the radial channels 4 open. The fuel from the above plunger volume passes through the passage channel 7 and the radial channels 4 to the injection fuel line and to the nozzle.

At the end of the fuel injection, the pressure in the above plunger volume drops, and the locking element 8 under the action of the spring 10 returns to its original position,

This embodiment of the discharge valve increases the uniformity of fuel injected into the nozzles of different cylinders, which contributes to reducing fuel consumption during operation of a multi-cylinder diesel engine.

Claims (3)

1. A high pressure fuel injection pump for a multi-cylinder diesel engine containing a cylindrical body located in the nozzle cavity with an axial chamber communicated with the nozzle cavity by means of a connecting passage, the body having radial openings for fuel flow, with a saddle on the side above plunger volume and bottom from the side of injection fuel line, and spring-loaded spool valve ten 883344 a shut-off element installed in the axial chamber with the possibility of axial movement and opening of the radial channels when the shut-off element moves from the seat to a predetermined distance, which, in order to improve performance by increasing the uniformity of fuel flow through the engine cylinders, the discharge valve is additionally equipped with a throttle valve a device for changing the flow area of the connecting channel with axial movement of the locking element. 2. Valve pop. 1, differing from that with the fact that the connecting channel is located in the bottom of the housing, and the throttle device is made in the form of a profiled needle connected to the locking element and placed with a gap in the connecting channel. 15 20 3. Valve according to claim. about tl and h and y Sch and with the fact that the connecting channel is located in the wall of the housing, and the throttle device is made in the form of an annular groove on the outer surface of the locking element with C, alternating cross section along the longitudinal axis and an additional channel that connects the axial chamber with the annular groove annular groove communicated with the connecting channel. cpuz.Z (rig. 3 one 13 1Z 4 Compiled by V. Dolgov Editor O. Yurkovetska Tehred L. Serdyukova Order 7782/29 Circulation 504Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab ,, d.4 / 5 Production and printing company, Uzhgorod, Projecto st., 4 Corrector C, Cherni .