JPS63143380A - Fuel injection pump device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a body, a single-stroke reciprocating index plunger housed within a bore of the body, the bore and the plunger forming a pumping chamber, and the plunger reciprocating during successive pumping strokes of the plunger. a distributor member for sequentially distributing fuel extruded from the pumping chamber to a plurality of outlet ports, deflecting the extruded fuel from the pumping chamber to a drain to control the amount of fuel delivered through said outlet; Relief valve electromagnetically actuated to provide low pressure 4 supplying fuel to the pumping chamber
The present invention relates to a fuel injection pump system of the type that includes a pump and a valve system that is activated in the event of a failure of the control system controlling the valve to continue supplying fuel to the installed engine.

A device of the above type is described in British Publication No. 2153017A. This device is for supplying fuel to the combustion chamber of a compression ignition engine.

Current compression ignition engines operate at significantly higher speeds and require precise fuel quantity and timing control to meet tight emissions regulations.

Precise fuel quantity and timing control is provided using an electromagnetically actuated relief valve and associated electronic control system. Higher injection pressures are required to achieve higher engine speeds and improved vaporization of the fuel to ensure good combustion of the fuel. This high injection pressure necessarily increases leakage within the device, particularly in the passageways that transport the high pressure fuel across the interface between the two parts of the device. If a stronger tightening force is applied between the above two parts.

This can cause distortion of these parts, cause excessive wear on moving parts of the device, and increase leakage within other parts of the device.

The present invention relates to a device of the above type and aims to provide a device of simple and convenient type.

A device of the above type according to the invention is such that the body is formed in three parts brought together in assembly relation, the first part being
a protrusion disposed within an aperture formed in the second part, said protrusion having an inner bore for receiving a deran soyer, and a distributor member mounted within another aperture of the second part, the plunger and the dispenser member being mounted within another aperture of the second part; A drive device for the instrument component is housed within the third barrel section, the relief valve includes a valve member slidable within a bore formed in the first barrel section, and the valve device is housed within the second barrel section. It is located in

One invention will be described below with reference to backbiting.

First of all, referring to FIG.
includes a plunger 11 that can reciprocate within the inner hole 12;
is connected by a spring-loaded delivery valve 14 to a fuel distributor, generally indicated at 15 and including a rotary distributor member 16. The distributor member distributes the fuel delivered during successive inward movements of the pumping plunger to a plurality of outlets 17, which outlets are further connected to respective fuel injection nozzles of the attached engine.

Plunger 11 is driven upward by a cam 19 connected to tappet mechanism 18 and attached to drive shaft 20 . It is also driven downward by a lever and another tappet mechanism (not shown) which is also actuated by this cam. The plunger shaft has a bevel gear 21 that meshes with another bevel gear 22 connected to the distributor member 16, and the drive shaft is driven in timed relationship with the mounted engine.

The shaft forming part of the distributor member carries an o-tor 23 of a low-pressure fuel supply pump with an inlet 24 and an outlet 25. In use, this inlet is connected to a fuel supply and the outlet is connected to a fuel reservoir, generally indicated at 26, which includes a piston 27 slidably mounted within a cylinder 28. The piston is biased toward one end of the cylinder 28 by a spring 29.

A port 30 is formed in the wall of the cylinder and is opened by the piston when it moves a predetermined distance against the action of a spring.

30 communicates with the inlet 24 of the low pressure pump.

The piston also acts to control the pump's discharge pressure. The end of the cylinder 28 equipped with a spring 29 communicates with the inlet 24 .

A plurality of ports 33A are formed in the wall of the bore 12, these ports communicate with the annular cavity 33 and they are connected to high pressure -
Configures the fuel inlet for the engine. The empty space 33 is the passage device 3
A valve 35, which communicates with the reservoir 26 via 4 and will be described below, controls the flow of fuel through the passage device 34.

The reservoir 26 communicates with a relief valve 38 via a passageway 37 and includes a spring-loaded valve member 3 having a head 40 that engages the seat when a solenoid device 41 associated with the valve is energized.
Contains 9. The spring forces the head 40 away from the seat and in this position fuel can flow from the passage 3 to the passage 37. As can be seen, the outlet 25 of the low pressure pump
is connected to the relief valve via passage 25A. The passage 37 is therefore also used to transfer fuel from the low pressure pump to the reservoir.

Plunger 11, when in its maximum outward position determined by cam 19, opens port 33A into the pumping chamber formed by the bore and the syringe. Valve 3
5 is open and the plunger is at the outermost limit of its stroke, and the pumping chamber is filled with fuel, rotation of the drive shaft 20 imparts an inward movement to the plunger 11. 33A is covered by the end of the plunger. The fuel in the pumping chamber is thereby displaced through the passage 13 and, if the relief valve is in the closed position, the fuel is discharged through the delivery valve 14 into the distributor member 15 and then into the outlet 17. . When the relief valve 38 is opened during or before the beginning of this displacement of fuel, the displaced fuel is deflected through the relief valve and the fuel is returned to the reservoir 26 through the passage 37. As a result,
No fuel flows to the outflow portion 17. The relief valve can be activated at any time to determine the timing of fuel delivery and the amount of fuel delivered. The plunger 11 is connected to the central passage 11
A, which passage forms a relief passage that opens into a groove formed around the periphery of the plunger at the position where groove 42 is opened prior to the end of the inward movement of the plunger. However, during normal use, the passage 11A is brought into communication with the groove 42 after the relief valve is opened and the fuel has finished being delivered.
Therefore, during normal use, the flow rate of fuel flowing from the depressing chamber along the passage 11A is small and will not pose a problem. A leakage groove 43 is provided in the inner bore 12 and connected to the fuel inlet 24 . Outflow of fuel from the passage 11A is performed by a valve 35 toward the storage section 26.

The outward movement of the plunger is effected by said separate tappet mechanism, and if relief valve 38 remains open, fuel will flow from passages 37 and 25A through passage 13 and into bore 12 by relief valve. It will be done. Port 33A
If the relief valve is closed during the outward movement of the plunger, all the fuel will flow into the bore when port 3 is opened by the plunger.
3A and into the bore, but this only occurs when that port is open.

A reservoir or accumulator 26 assists the low pressure pump in filling the bore 12, which in normal use is fully flushed with fuel prior to inward movement of the dessinger. The reservoir is refilled by a low pressure pump neutralizing the inward stroke of the plunger.

In the event of a failure of the control system powering the solenoid device 41 and/or the solenoid itself, the relief valve 38 will be moved to an open position by virtue of its spring loading, thereby denying fuel to the attached engine. The engine is thus protected against overspeed operation which may lead to its own destruction.

The valve 35 mentioned above is arranged so that the fuel supply to the engine can be restricted in case of an emergency situation.

The valve 35 includes a rotationally movable valve member 135 whose position is determined by the setting of the vehicle's throttle pedal regardless of whether the control system or relief valve is functioning correctly or incorrectly. As such, it is directly connected to the vehicle's throttle pedal, which is driven by the engine. As can be seen in FIG.
35 and the surrounding sleeve or 4-port in the body, and thereby change the degree of alignment of these dates, and thus the effective restriction of fuel flow, by changing the setting of the rotational position of the valve member. If the control system and relief valve are operating properly, the flow of fuel through port 33A and into bore 12 will be very small, so that the valve member positioning will remain within the bore at the end of the fill stroke. It has little or no effect on the amount of fuel contained within the hole 12. However, in the event of a failure of the control system, the relief valve 38Fi is moved to the closed position by a manual device described below, so that all fuel entering the bore 12 is forced to pass through the valve 35. , the positioning of valve 35 determines the amount of fuel that enters bore 12 and thus the amount of fuel that is supplied to the installed engine.

Valve 35 is also used to control the flow of fuel from groove 42 to the reservoir such that passage 11A in plunger 11 connects groove 42 toward the end of the inward movement of the plunger. It takes place when brought into communication. Moreover, the valve 35 provides a variable flow path from the reservoir 26 to the inlet 24 of the low pressure pump, which flow path is connected to the metering restrictor 13.
Contains 6.

The operation of the valve member 135 will be described below with reference to FIGS. 7 and 8. First, in FIG.
5 has a shaft 137 extending around the periphery of the device to which a lever 138 is connected. This lever is connected to one end of another lever 140 via a link 139, and the lever 14
0 is rotatably mounted on the exterior of the device at the center of its ends and the other end is connected to the throttle pedal 141 by a cable connection. A sensor (not shown) is provided which provides an electrical signal to the control system indicative of the position of the throttle pedal.

A further lever 142 is mounted on the shaft 137 and is connected by a cable to driver-operated control means 143. This further lever is an adjustable stop member 14.
4, which is engaged by the lever 138 when the control means 143 is moved into the operative position shown in FIG. When this control means is moved into the active position, the lever 142 moves the relief valve member into the closed position. 7 and 8 show the foot off the throttle position, and in FIG. 7 the idle speed of the engine is controlled by the control system. Movement of the control means 143 into the operative position engages the stop member 144 with the lever 138 and moves this lever to the emergency engine idle position, in which just enough is applied via the valve 35 to idle the engine. Port 3
Flow to 3A. This amount of flowing fuel is determined by the set position of the stop member 144. When the throttle 4 pedal is depressed,
Valve 35 moves to increase fuel flow to the attached engine. The limits of movement of the lever 140 and thus of the other levers connected to it are determined by the stop member 145. If the parts are set up as shown in FIG. 8, the control means 143 will be returned to its inactive position and the various other levers will be returned to the positions shown in FIG. This moves the relief valve 38 to the open position so that no fuel is supplied to the engine. However, when closed, such as due to a control system failure or failure of the valve or its actuator, the valve 35 prevents the flow of fuel to the bore 12 and thus the engine. During normal operation with the levers set as shown in FIG. This is achieved by cutting off the

In the emergency operation state with the relief valve 38 closed, the passage 11A
when brought into communication with groove 42 forms a relief path from the pumping chamber. The practical effect of this is that for a given amount of fuel delivered to the engine, the delivery of fuel is faster than if the same amount of fuel were delivered but there was no escape of fuel through passage 11A. It will be implemented in a timely manner. Delivering fuel quickly means minimizing engine smoke. However, since the escape of fuel through one passage 11A terminates fuel delivery, more fuel must be supplied to the bore than if fuel were delivered from the outlet.

During normal operation, the amount of fuel that escapes from one passage 11A can be ignored, but in an emergency operation state, the amount of fuel that escapes from valve member 1
35 so as to be narrowed down. The degree of throttling is arranged such that the degree of throttling decreases as the valve member 135 is moved in a direction to increase fuel to the engine. Fuel escape is prevented during normal operation when the throttle pedal is in the position shown in FIG. 7 and when starting the installed engine. In this case, the relief valve 38
is closed before the plunger 11 begins its upward movement and without any escape of fuel, and the total amount of fuel displaced by the plunger is displaced from the outlet 17, so that overpressurized fuel for starting is removed. sent to the engine.

The valve 35 is also used to change the discharge pressure of the low pressure 4 ring to a specific value. For this purpose, this valve connects the inlet 2 of the low-pressure pump from the reservoir 26 via the restrictor 136.
Control the flow rate to 4. This valve is set so that the above-described fuel flow begins to occur when the throttle pedal is depressed from the position shown in FIG. This valve is
Although it continues to provide a restriction to reduce flow when the throttle pedal is depressed, the effect of this valve is tapered by the action of the strifter 136.

The combined effect of varying the fuel release and the low-pressure pump discharge pressure is! To improve the control effect carried out by a driver when a vehicle is being driven in an emergency driving condition.

It will be appreciated that when the engine is operated in emergency operating conditions its performance is limited. It would still be possible to generate enough power to drive the vehicle.

With devices of the type described, it is important to try to keep the volume of the passageways of the device for transferring high-pressure fuel as low as possible. This is to reduce the so-called "unnecessary volume" of fuel. It is also important to try to minimize the number of seals that are subject to the high pressures that are generated when the relief valve is closed and fuel is being delivered to the attached engine.

Furthermore, since this device is intended to deliver fuel under extremely high pressure, the device must be assembled and tightened properly.
It is important to ensure that carefully machined internal bores etc. do not warp when the bolt is tightened.

FIGS. 2 through 6 show the actual arrangement of the two body parts of the device, which accommodate the passageways and bores shown above the dashed line 50 in FIG. In Figures 2 to 6,
The first body portion 51 has through openings 5 arranged at one interval.
2.53, the aperture 52 is used to receive the distributor member 16 mounted within the sleeve 53, and the aperture 53 has a cylindrical shape integral with the body portion 55 and extending from one side thereof. It is used to accommodate the shaped protrusion 54.

The barrel part 51 furthermore has on its upper surface a recess 56 for accommodating the delivery valve 14 and is provided with an outlet 17 . As can be seen in Figure 2, this body section has a generally rectangular cross-sectional shape and has holes for receiving a tightening delt, whereby the body section is secured to another body section (not shown) of the device. This further body portion is located below dashed line 50 in FIG. 1 and houses the drive shaft 20, cam mechanism and drive for the distributor member. Further, the body portion 51 includes a valve member 135.
It has a cylindrical cavity 58 into which a sleeve 59 containing a cylindrical cavity 58 is fitted. The valve member is held in place by a perforated cap 60 which extends outside the barrel and includes an annular sealing member.

A protrusion 54 of barrel portion 55 is located within opening 53 and is grooved in the protrusion for receiving an O-ring seal. An internal bore 12 accommodating a pumping plunger 11 is formed in the protrusion and in this shank part? The barrel portion 55 has a hole 61 for receiving the bolt, so that the barrel portion 55 has a hole 61 for receiving the bolt.
is fixed to the top surface of the What about hole 61? To minimize the risk of distortion of the bore when the bolt is tightened,
It should be noted that it is well separated from

The body portion 55 has a lateral bore 62 whose axis is perpendicular to the axis of the bore 12 and whose distal end is located midway between the ends of the lateral bore 62 by a bore 13A formed in the passageway 13. Connected with points. The lateral inner hole 62 is connected to the relief valve member 3
9 and provide a seat for the head of the valve member 39. The position sensor 63 is connected to the torso portion 55
The sensor has a movable component attached to the valve member. Furthermore, one actuator 41 is carried in the barrel section 55 and has its armature connected to the valve member.

A cylinder 28 of a fuel reservoir or achievator 26 is further formed in the body part 55 .

The axis of the cylinder 28 is arranged at right angles to the axes of the bores 12 and 62, and the inner end of the cylinder is connected by a short bore 37A opening into the transverse bore 62;
This perforation constitutes the passage 37 mentioned above. The opposite end of the cylinder is closed by a cap 64 which provides a bearing for a rotatably movable shaft 65 located on one side of the cylinder 28 and extending inwardly into the actuator 41 as shown in FIG. do. The shaft 65 is connected to the valve member 39 by a mechanism not shown.

The high-pressure fuel flowing through the outlet flows through the passage 66 of the body portion 55.
through a transverse bore 62 into the delivery valve chamber 56 , which passage 66 opens onto the underside of the barrel section 55 opposite the end of the chamber 56 . At this point, a sealing ring (not shown) is provided for high pressure sealing. Fuel is routed from chamber 56 via passage 57 to ports in the sleeve surrounding the distributor member. This sleeve is exposed to each outlet 1
Provide a port connected to 7.

The inner bore 12 has holes 33A as described above, which are located on the periphery of the protrusion 54 and between the protrusion 54 and the opening 53, as shown in FIGS. 4 and 5. It is formed and opens into a round annular cavity 33. The groove 42 in the wall of the inner hole 12 is
The bent portion is connected to the valve 35 via the passageway 42A.

A pair of spaced apart elongated troughs 146, 147 are formed on the lower surface of the body portion 55 and are disposed generally parallel to the axis of the valve member 135. Gutter 146 is slightly longer than gutter 147 but has a smaller depth, and is connected to storage cylinder 28 via one passage 148.

A passageway 149 extends into body portion 51 and downwardly from trough 146, which communicates with a port 150 formed in sleeve 59 within which valve member 135 is supported. Additionally, a port 151 is formed within the valve member 135, which extends through the axial bore of the valve member, the port, and the perforation forming part of the passageway 34 into the annular cavity. It is connected to 33.

Additionally, another passage 153 is provided within the body portion 51 and through the trough 14.
Another port 152A (No. 1.9, 10.11) extending downwardly from J-port 6 and disposed in communication with the J-port 152 of the sleeve and connected to the passageway 42A at a corresponding axial position in the sleeve 59; ) are arranged. Finally, a third passage 154 extends downwardly from the gutter 146 within the body portion 51 and communicates with the sleeve 155. A port 156 is located at a corresponding axial location on the sleeve;
The hoard beam communicates with a passage 157 that includes the strifter 136 and communicates with the gutter 147 . Whisper 147 communicates with the inlet 24 of the low pressure supply pump.

another port) 152A and port 152 and port 1
In the axial position corresponding to 55 and 156, the valve member 135 has grooves 158, 159 shown in the illustrations in FIGS. 9.10 and 11. As shown in FIG. 9, the valve settings correspond to FIG. 7 with the throttle pedal released and the engine controlled by the control system to idle speed. FIG. 10 shows the valve settings corresponding to FIG. 8, in this case providing a limited flow of fuel for idling in emergency operating conditions, and FIG. Shows the position of the valve when it is depressed to its maximum amount. Beau) 150
, 151 is perfectly aligned, the flow of fuel through it is insufficient to cause no-load overspeed of the attached engine, but at the same time the engine is producing sufficient power to drive the vehicle. able to demonstrate.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram of the fuel circuit of the pump device, and Figure 2 is:
3 is a side view taken in the direction of arrow A in FIG. 2; FIG. 4 is a side view taken in the direction of arrow B in FIG. 3; and FIG. 2, FIG. 6 is a partial view of the apparatus shown in FIGS. 2, 4 and 5;
7 and 8 show the linkage connecting the parts of the device, and FIGS. 9, 10 and 11 show the set positions of the valves forming part of the device. Codes in the figure: 10...High pressure fuel injection pump, 11...
- Plunger, 12...inner hole, 13...outflow passage,
14... Delivery valve, 15... Fuel distribution member, 16...
- Rotation distribution member, 17...Outflow section, 18...Tappet mechanism, 19...Cam, 20...Drive shaft, 21.2
2... Bevel tooth force, 23... Rotor, 24... Inflow section, 25... Outflow section, 26... Fuel storage section, 27...
・Piston, 28...Cylinder, 29...Spring, 3
0...Bow), 33...Space, 33A...?
-t, 34...passage device, 35...valve. 37... Passage, 38... Relief valve, 39... Valve member, 40... Valve head, 42... Groove, 50... Line, 51... Second body portion, 52...・・Opening, 53・・
- Opening, 54... Protrusion, 55... First body portion, 5
6... recess, 57... boss, 58... cavity, 59
... Sleeve, 61 ... Hole, 62 ... Lateral inner hole, 63 ... Position sensor, 64 ... Cap, 65 ...
... Shaft, 135 ... Valve member, 136 ... Restrictor, 137 ... Shaft, 138 ... Lever, 139 ...
- Link, 140... Lever, 141... Throttle idal, 142... Lever, 143... Manual control device, 144... Stop member, 145... Stop member,
146...Gutter, 147...Gutter, 148...Passage,
149...Aisle, 150..., j? -), 151・
...port, 152...port, 153...passage,
154...Aisle, 155...Port, 156...
Bow), 157... passage. FIC,,1 FIG4゜FIG, 5゜FIGδ. FIG, 9゜β [[L

Claims (1)

[Claims] 1. A pump plunger 11 which is housed in an inner hole 12 and is capable of reciprocating motion with a constant stroke and forms a pump chamber with the inner hole, and a pump plunger 11 that is housed in a plurality of outflow ports 17 in sequence. ,
A distributor member for distributing the fuel forced out of the pumping chamber during successive pumping strokes of the plunger 11, an electromagnetic relief valve acting to deflect to control the amount of fuel delivered through said outlet. 38, a low pressure pump 23 for supplying fuel to the pump chamber, and a valve member 35 which is activated in the event of a failure of the control system controlling the valve member 38 to cause the device to continue to supply fuel to the attached engine; is formed of three parts joined together in assembly relation, the first part 55 of the body having a projection 54 disposed within an opening 53 formed in the second part 51 of the body; has an inner bore 12 containing a plunger 11, a distributor member 16 is mounted within another opening 52 in the second barrel portion;
characterized in that the relief valve includes a valve member 39 slidable within a bore 62 formed in the first body part 55 and the valve arrangement 35 is disposed in the second body part 51. Kinds of fuel injection pump equipment. 2. It has a port 33A extending from the inner hole 12 and a cavity 33 formed between the surface of the protrusion 54 and the opening 53, and the port communicates with the cavity and 2. The fuel injection pump device according to claim 1, wherein the fuel injection pump device communicates with the fuel accumulator 26 via the valve device 35. 3. The fuel injection pump according to claim 2, wherein the accumulator 26 includes a cylinder 28 formed in the first portion 55 of the body, and includes a piston slidable within the cylinder. Device. 4. The cylinder 28 further includes a cap 64 extending inwardly from one side of the first portion of the body and closing the open end of the cylinder. Fuel injection pump device. 5. The patent characterized in that the inner holes 12 and 62 are arranged at right angles to each other and further include a short passage 13A connecting the inner end of the inner hole 12 and the midpoint of both ends of the inner hole 62. A fuel injection pump device according to claim 1.