JPH03138427A - Control device for stopping internal combustion engine - Google Patents

Abstract

PURPOSE: To prevent valve functions from being impaired by foreign matter by constructing the valve member of a control valve in such a way that it includes a seat valve closer for controlling the connection between a tank conduit and the suction conduit of a feed pump, the control valve being mounted in a fuel feed conduit connected to a fuel injection pump. CONSTITUTION: An internal combustion engine has a fuel injection pump 11 such that fuel in a tank 26 is fed to its suction chamber 33 by a feed pump 13 via a control valve 12. The control valve 12 has a valve member 16 which can be freely switched from a delivery position to a shutoff position for an engine stop. The fuel in the suction chamber 33 is returned to the tank 26 by an overflow conduit 34. In this case, the valve member 16 of the control valve 12 is provided with a seat valve closer 18 which cooperates with two valve seats 19. 21 in order to control the connection between a tank conduit 27 and the suction conduit 27 of the feed pump 13 and which is integrated with a control slider 23. The seat valve closer 18 is provided to open the valve seat 19 at the delivery position of the control valve 12 and to close it at the shutoff position.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a control device for stopping an internal combustion engine, in particular a diesel engine, which draws fuel from a tank via a tank conduit and a suction conduit and which uses a pressure conduit and a connecting conduit. a feed pump discharging to the inlet of the suction chamber of the fuel injection pump; and a control valve configured as a two-position directional control valve and connecting the tank conduit to the suction conduit and the pressure conduit to the connecting conduit in the discharge position;
The control valve has a valve member axially movably guided in the valve casing for switching from a discharge position for operating the internal combustion engine to a shutoff position for stopping the internal combustion engine; At a position where the suction chamber of the fuel injection pump is connected to the suction conduit of the feed pump and the pressure conduit of the feed pump is connected to the tank conduit, and is located in the overflow conduit that returns fuel from the suction chamber to the tank, the pressure in the suction chamber is Relates to types equipped with a limiting overflow valve.

In a control device known from German Patent Application No. A-30 14 712, the direction of action of the feed pump can be changed by switching a line using a control valve in order to stop the internal combustion engine; The suction chamber of the feed pump is connected to the suction side of the feed pump, and the discharge side of the feed pump is connected to the tank.

As a result, fuel is rapidly discharged from the suction chamber of the fuel injection pump, so that due to the resulting negative pressure, the fuel injection pump can no longer deliver fuel and the associated internal combustion engine stops. In order to achieve this functional sequence, the control valve is designed as a 4-port, 2-position valve.

In the control device described in German Patent Application No. A-3014712 and United States Patent Application No. A-4319550, the control valve has a piston slider as a valve member, and the control valve is filtered into the control valve. A fuel filter must be provided on both the suction side and the discharge side of the feed pump upstream of the control valve in the direction of fuel flow.

Functional drawbacks arise due to the necessity that the control valve must also be protected against dirt particles by a fine filter on the suction side of the feed pump, and due to paraffin separation at low temperatures, the filter is only exposed to negative suction pressure. will become clogged. This can impede fuel delivery and, in extreme cases, lead to an undesirable interruption.

In the control device known from European Patent Application No. A-0124504, a component unit of a 4-port 2-position directional control valve and a 3-port 2-position directional control valve or a 6-port 2-position directional control valve is required. This control device also requires an additional fine filter, which gives rise to the disadvantages mentioned above.

In order to obviate the aforementioned drawbacks of the known art, it is provided that the valve member of the control valve is provided with a seat valve closing body for controlling at least the connection between the tank conduit and the suction conduit of the feed pump; The closing body opens the associated valve seat in the valve housing in the discharge position of the control valve and closes this valve seat in the shut-off position.

With this embodiment of the invention, the operational and functional reliability of the control device is increased, especially during cold start-up, with low construction costs. This is because a fine filter is no longer required on the suction side of the feed pump and dirt particles sucked in from the tank no longer interfere with the functioning of the valve.

The arrangement according to claim 2 provides a valve member which can be produced satisfactorily and which reliably guides the seat valve closing body; A control valve designed as a control valve is particularly advantageously integrated in an injection pump which is equipped with a throttle in the inlet channel in order to obtain a cross flow in the individual partial suction chambers.

With the structure described in claims 5 and 6,
A control valve is obtained which is unaffected by dirt, which is based on the combination of two seat valves for operation, does not require filters either on the upstream or downstream side, and thus has a high functional reliability. ing.

With the configuration described in claim 8, an inexpensive control valve that can be easily incorporated is obtained, and the configuration described in claim 9
With the configuration described in section 2, the sealing performance required for the valve seat is guaranteed even with unavoidable manufacturing tolerances.

Embodiment As shown in FIGS. 1 to 8, a control device 14 is disposed within the fuel circuit of a fuel injection pump 11, and the control device includes a control valve 12 and a feed pump 13. The control valve 12 is constructed as a solenoid valve, the valve member 16 of the control valve being brought into the discharge position for operation of the internal combustion engine against the force of a return spring 17 and shut off for stopping the internal combustion engine by the force of the spring. Can be moved to any position.

In the first embodiment of FIG. 1, control valve 12 is configured as a four-port, two-position directional control valve, with valve member 16 shown in the discharge position. At its end facing the return spring 17, the valve member 16 has a seat valve closure 18 which is configured as a double seat valve closure.
The seat valve closure body is adapted to cooperate with opposing first and second valve seats 19 and 21 arranged in the valve casing 22. The seat valve closing body 18 is connected to the valve member 16
is supported and simultaneously guided by a control slide 1 2 23 arranged coaxially and positioned at the end opposite the return spring 17 of the control slide 1 2 23, which is preferably provided with at least one arc-shaped recess. 25, this cutout allows fuel flow between the connections switched by the control slider 23.

In the discharge position of the valve member 16 the first valve seat 19 is open and the seat valve closing body 18 is in close contact with the second valve seat 21, thus opening the valve chamber 24 which is enlarged by the return spring 17.
tank conduit 2 which is closed and connected to tank 26
7 is connected to a suction conduit 28 leading to the suction side of the feed pump 13.

A filter 31 is arranged in the pressure line 29 downstream of the feed pump 13 and is designed as a fine filter. In the delivery position of the valve member 16 , the pressure line 29 is separated from the connecting line 32 by the control slide 23 , which leads into the suction chamber 33 of the fuel injection pump 11 . An overflow conduit 34 extends from the suction chamber 33 to the tank 26 , and has a conduit within the overflow conduit that limits the pressure within the suction chamber 33 .
An overflow valve 36 is arranged which opens towards the end.

Tank conduit 27, suction conduit 28, pressure conduit 29 and connection conduit 32 are connected in series to four connections 35a, 35b, 3
It is connected to the valve casing 22 via 5c and 35d.

In FIG. 2, the valve member 16 is in the blocking position. The seat valve closing body 18 is in intimate contact with the first valve seat 19 and the second
The valve seat 21 is open, thereby opening the connection between the connecting channel 37, which leads from the connecting conduit 32 into the valve chamber 24 through the valve housing 22, and the suction conduit 28.

Via the pressure line 29 , the feed pump 13 delivers fuel, depending on the position of the control slide 23 , into a tank line 27 connected to the pressure line 29 and thus into the tank 26 .

A second embodiment is shown in FIG. 3 in the discharge position and in FIG. 4 in the shut-off position. The second embodiment has a 5-port 2-position directional control valve as the control valve 12, which has a 5-port 2-position directional control valve for the tank line 27, the suction line 28, the pressure line 29 and the connecting line 32. four connection parts 35a
In addition to 35b, 35c, and 35d, an overflow valve 36
It has a fifth connection 41 for a pressure relief conduit 42 which is connected upstream of the suction chamber 33 and opens into the valve chamber 24 .

In the discharge position of FIG. 3, the pressure relief conduit 42 is blocked by the seat valve closing body 18 which abuts the second valve seat 21, whereas in the blocking position of FIG. seat 19
The feed pump 13 discharges fuel from the valve chamber 24 into the tank 26 as in the first embodiment. In this case, the suction chamber 33 is connected to the valve chamber 24 by a pressure relief line 42, and a third embodiment is shown in FIG. 5 in the discharge position and in FIG. 6 in the shut-off position. In the third embodiment, the control valve 12
is constructed as a 5-port 2-position valve member 16, in addition to the seat valve closing body 18, has a second seat valve closing body 46 which is also constructed as a double seat valve closing body, and this seat valve The closing body is arranged in the valve casing 22 and is adapted to cooperate with two valve seats 47, 48 located opposite each other, one of which is arranged in the outlet position of the control valve 12 in the pressure conduit 2.
9 and the connecting conduit 32 is open and this connection is closed in the shutoff position, and the other valve seat 48 is closed in the shutoff position of the control valve 12 at the connection between the pressure conduit 29 and the tank 27. is open and this connection is closed in the discharge position. The valve member 16 of the control valve 12 has both seat valve closure bodies 1
8.46 in the diaphragm 51 or 52, which radially surrounds the seat valve closing body, is configured to be elastically deformable, has a through hole, and allows the valve member 16 to move in the axial direction. Guided in the radial direction.

Unlike the first and second embodiments, the filter 31 is not located in the pressure conduit 29 between the feed pump 13 and the control valve 12, but in the connection conduit downstream of the control valve 12 for the protection of the fuel injection pump 11. It is located within 5-632.

A fourth embodiment is shown in the discharge position in FIG. 7 and in the shutoff position in FIG. In the fourth embodiment, the control valve 12 is configured as a 6-port, 2-position directional control valve, with the first
Similarly to the second embodiment, it functions as a valve seat slide valve.

The control valve has on the valve casing 22, in addition to four connections 35a, 35b, 35c, 35d for the tank conduit 27, the suction conduit 28, the pressure conduit 29 and the connecting conduit 32.
The first connecting to the suction chamber 33 of the overflow conduit 34
a fifth connection 41 for the sump of the conduit section 81 of the overflow conduit 34 and a sixth connection 83 for the second conduit section 82 leading to the overflow valve 36 of the overflow conduit 34; Sections 81, 82 are connected to each other both in the delivery position and in the shutoff position of the control valve 12.

Modifications to the embodiments shown in FIGS. 7 and 8 are shown in FIGS. 9 and 1θ.

The seat valve closure body 18 is partly covered on the outside by an elastomeric part 56 and has a sealing lip 59 . formed integrally with the elastomeric part 56 and directed towards the first valve seat 19 and the second valve seat 21 . 61. The sealing lip 59.61 has a projection 62 that projects slightly from the end face 57.58. The portions of the end faces 57 and 58 that are not covered by the elastomeric portion 57 are the valve seat 19.
Alternatively, in the case of a form-locking connection with 21, a metallic stop is formed. The elastomer-coated seat valve closure body 18 is a first
It is also advantageously used in the embodiments shown in FIGS.

The second valve seat 21 has a forest-like insert 6 as shown in FIG.
7, the insert delimits the valve chamber 24 with its inner wall. The insert is preferably constructed as a deep-drawn part made of sheet metal and is fixed in the axial direction by a profiled plate 71 which is removably attached to the control valve 12 and which allows the valve member 1
6 and a spring catch 68 for the return spring 17, which tightly closes off the valve chamber 24.

The valve member 16 includes a first guide collar 72 and a second guide collar 7.
3, and a pressure conduit 29 and a connecting conduit 3 located between the guide collars and corresponding in function to the control slide 23 of the first embodiment.
It has a valve slider 74 that controls the connection with 2.

It is an advantage of the invention that the valve member 16 of the control valve 12 of the first embodiment (FIGS. 1 and 2) is provided with a seat valve closure 18 that is not affected by dirt, so that the tank line 17 is provided with a filter. There is no need to provide A pressure conduit 29 leading to the feed pump 13 connects the control slider 23 and the fuel injection pump l.
It has a filter 31 necessary for the operation of 1.

A further advantage of the invention is that the control valve 12, which is a 4/2-position directional control valve, has an internal connection channel 37, via which the feed pump 1 can be connected in the event of a stop.
3, the suction chamber 33 of the fuel injection boat 11 is discharged.

In the second embodiment shown in FIGS. 3 and 4, instead of the connecting passage 37, a fifth connecting portion 41 is provided, and five ports and one
- The same operating sequence as for a control valve configured as a two-position directional control valve is obtained.

The valve member 16 of the control valve 12 configured as a 5-photo 2-position directional control valve of the third embodiment shown in FIGS.
The control valve 12 has two seat valve closure bodies 18, 46, so that the seat valve closure body valves are not affected by dirt.
It is not necessary to provide a filter before the fuel injection pump 11; the filter 31 is arranged in the connecting line 32 only immediately before the suction chamber 33 in order to maintain operational reliability of the fuel injection pump 11.

In a fourth embodiment, shown in FIGS. 7 to 10, the conduit guidance is simply carried out using a 6-port, 2-position directional control valve, in which case the seat is seated as shown in FIGS. A satisfactory sealing function of the control valve 12 with the valve closing body 18 is obtained.

When the seat valve closing body 18 comes into contact with the end face 66 of the valve seat 21 , the second sealing lip 61 first comes into contact with the end face 66 . This second sealing lip is elastically deformed, the projection 62 is retracted, and the axial movement of the valve member is prevented by the form-locking connection between the metal surface of the seat valve closure body and the metal surface of the valve seat.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention, and FIG. 1 is a sectional view of the second embodiment at the discharge position, FIG. 2 is a sectional view of the first embodiment at the cutoff position, and FIG. The figure is a sectional view of the second embodiment at the discharge position, FIG. 4 is a sectional view of the second embodiment at the cutoff position, and FIG. 5 is a sectional view of the third embodiment at the discharge position.
6 is a sectional view of the third embodiment at the cutoff position, FIG. 7 is a sectional view of the fourth embodiment at the discharge position, and FIG. 8 is a sectional view of the fourth embodiment at the cutoff position. , FIG. 9 is a longitudinal cross-sectional view of a modification of the embodiment shown in FIG. 7, and FIG. 1O is a cross-sectional view of a portion of the seat valve closing body of FIG. 9. 11... Fuel injection pump, 12... Control valve, 13...
...Feed pump, 14...Control device, 16...
Valve member, 17... return spring, 18... seat valve closing body,
19 and 21... Valve seat, 22... Valve casing, 2
3... Control slider, 24... Valve chamber, 25... Notch, 26... Tank, 27... Tank conduit, 28
...Suction conduit, 29...Pressure conduit, 31...
Filter, 32... Connection conduit, 33... Suction chamber, 34... Over 70-conduit, 35a, 35b, 35c
and 35d... connection part, 36... overflow valve,
37... Connection passage, 41... Connection portion, 42... Pressure relief conduit, 46... Seat valve closing body, 47 and 48... Valve seat, 56... Elastomer portion, 59 and 61 ...Seal lip, 62...Protrusion, 66...End face, 67
... Inserts 81 and 82 ... Conduit section, 83 ...
Connection part FfG, 9

Claims (1)

[Claims] 1. A control device for stopping an internal combustion engine, which sucks fuel from a tank (26) through a tank conduit (27) and a suction conduit (28) and a pressure conduit (29).
and a fuel injection pump (11) via a connecting conduit (32).
a feed pump (13) discharging into the inlet of the suction chamber (33) of the tank, and a feed pump (13) configured as a two-position directional control valve which in the discharge position draws the tank conduit (27) into the suction conduit (28);
and a control valve (12) connecting the pressure conduit (29) to the connection conduit (32), the control valve being connected to the valve casing (
a valve member (16) axially movably guided within the valve member (16);
), and is designed to switch from a discharge position for operating the internal combustion engine to a cutoff position for stopping the internal combustion engine, and in the cutoff position, the suction chamber (33) of the fuel injection pump (11) is closed to the feeder. The suction conduit of the pump (13) (
28) and the pressure conduit (29) of the feed pump is connected to the tank conduit (27) and arranged in the overflow conduit (34) which returns fuel from the suction chamber (33) to the tank (26), (33) with an overflow valve (36) for limiting the pressure in the control valve (12), the valve member (16) of the control valve (12) at least in the tank conduit (27) and in the suction conduit of the feed pump (13). (28) is provided with a seat valve closing body (18) to control the connection with the control valve (12).
The associated valve seat (1) in the valve casing (22) in the discharge position of
9) A control device for stopping an internal combustion engine, characterized in that it is open and is adapted to close this valve seat in a shutoff position. 2. The valve member (16) carries the seat valve closure body (18) and at the same time has a control slide (23) which serves as a guide part for the seat valve closure body, the control slide being connected to the pressure conduit (2).
9) and the connecting conduit (32) and the tank conduit (27). A control valve that operates as a 3 or 4 port 2 position directional control valve (
12) has a connecting channel (37) which leads from the connecting conduit (32) into a valve chamber (12) which is delimited by the second valve seat (21) and is closable by a seat valve closure (18).
24) Control device according to claim 2. 4. The control valve (12) is configured as a 5-port 2-position directional control valve, and the valve casing (22) is connected to the tank conduit (
27), four connections (35a, 3) for suction conduit (28), pressure conduit (29) and connection conduit (32).
5b, 35c, 35d) as well as a fifth connection (41) for a pressure relief conduit (42) connected to the suction chamber (33) in front of the downstream overflow valve (36). and a pressure relief conduit leads to a valve chamber (24) which is limited by a second valve seat (21) and which is closed by a seat valve closing body (18) in the discharge position of the control valve (12), opening the valve chamber. The suction chamber (33) is connected to the suction conduit (28) of the feed pump (13) by means of the pressure relief conduit (42) in the shut-off position.
3. A control device according to claim 2, wherein the control device is adapted to be connected to. 5. The seat valve closing body (18) is configured as a double seat valve closing body and is adapted to cooperate with two opposing valve seats (19, 21) arranged in the valve casing (22). The second valve seat (21) opens the connection between the suction chamber (33) of the fuel injection pump (11) and the suction conduit (18) of the feed pump (13) in the blocking position of the control valve (12). and is adapted to close this connection in the discharge position, the valve member (16) being connected to the suction conduit (28).
In addition to the first seat-valve closure (18) associated with the valve, it has a second seat-valve closure (46), which is designed as a double-seat closure and which Casing (22
), the valve seat (47) of the second seat valve closing body (46) cooperates with two valve seats (47, 48) located oppositely in the control valve (12). Pressure conduit (
29) and the connecting conduit (32) are open and this connection is closed in the cutoff position, and the other valve seat (48) is closed under pressure in the cutoff position of the control valve (12). 2. The control device according to claim 1, wherein the connection between the conduit (29) and the tank conduit (27) is opened and this connection is closed in the discharge position. 6. The valve member (16) of the control valve (12) is connected to the diaphragm (51, 52) in the area of both seat valve closing bodies (18, 46).
A patent in which the diaphragm radially surrounds the seat valve closing body, is configured to be elastically deformable, is provided with a through hole, and radially guides the valve member (16) for axial movement. A control device according to claim 5. 7. A cylindrically designed control slide (23) surrounds at least one preferably arc-shaped control slide serving for the flow of fuel from the pressure conduit (29) to the connecting conduit (32) or to the tank conduit (27). 3. A control device according to claim 2, comprising a cutout (25). 8. The control valve (12) is configured as a 6-port 2-position directional control valve, and the valve casing (22) has a tank conduit (27), a suction conduit (28) and a pressure conduit (29).
, and four connections (35a) for the connection conduits (32).
, 35b, 35c, 35d), as well as a fifth connection for the first conduit section (81) of the overflow conduit (34), which connects to the suction chamber (33) in front of the overflow valve (36). (41) and a second conduit section (82) leading to the overflow valve (36) of the overflow conduit (34).
), with both conduit sections (81, 82) of the overflow conduit (34) being connected to each other both in the discharge position and in the shut-off position of the control valve (12). A control device according to claim 2. 9. Control device according to claim 2, wherein at least the second valve seat (21) is formed in the bottom end face of the bowl-shaped insert (67) delimiting the valve chamber (24). 10. Claim in which at least the seat valve closure body (18) is partially coated with elastomer and is provided with an elastically deformable sealing lip (59, 61) directed toward the valve seat (19, 21). 2. The control device according to item 2.