JPH0849619A - Fuel injection pump - Google Patents

Abstract

PURPOSE:To prevent poor rotation of a rotor by securing an oil film on a thrust washer front surface. CONSTITUTION:The rotor 90 of a fuel injection pump 10 is rotatably inserted into a housing 11 so as to extend on the same axis as a driving shaft 70. A pulser 120 is fitted and fixed to the outer periphery of the collar part of the driving shaft 70, and a thrust washer 87 for receiving a thrust load is interposed between the collar part and the side wall 86 of a feed pump 80. Spiral grooves are formed on the front and back surfaces in the thrust washer 87, and fuel acting as lubricating oil is allowed to flow into respective grooves from the outer peripheral side openings of respective grooves as the driving shaft 70 is rotated, and the oil films formed on both front and rear surfaces are prevented from being moved outward from the spiral grooves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel injection pump,
Particularly, it relates to a fuel injection pump suitable for a fuel injection pump of a diesel engine.

[0002]

2. Description of the Related Art An inner cam type distribution type fuel injection pump has been known as a type of fuel injection pump for diesel engines. In this type of fuel injection pump, for example, as described in Japanese Utility Model Laid-Open No. 59-168544, when the rotation of the engine is transmitted to the drive shaft, the rotor connected to the drive shaft is driven to rotate. It has become. In addition, as the rotor rotates, a roller provided in the rotor rolls on the cam surface of the cam ring, and a plunger inserted in the rotor reciprocates according to the cam shape, so that fuel pressurized by fuel is injected into the fuel injection nozzle. It is designed to be supplied to.

In the fuel injection pump having the above structure, a helical gear is provided at the end portion of the drive shaft, and a force for pulling out the drive shaft in the axial direction is exerted during rotational driving,
The drive shaft is pressed against the rotor by the pressure generated in the rotor. For this reason, the drive shaft is provided with a flange portion that projects in the radial direction, and a thrust washer is interposed between this flange portion and the non-rotating portion so that the load in the thrust direction (axial direction) can be received via the thrust washer. It has become.

Further, in this structure, light oil as a fuel is supplied to each sliding portion as a lubricating oil, and an oil film due to the fuel is formed on the surface of the thrust washer.

[0005]

In the diesel engine which burns the fuel supplied from the fuel injection pump having the above structure, the combustion efficiency of the fuel injected into the combustion chamber of the engine is improved in order to improve the performance of the engine. There is a need. Therefore, in the above fuel injection pump,
The pressure of the fuel supplied to the fuel injection nozzle is set to, for example, 100
Research has been conducted to raise the pressure to about 0 atm.

However, in the above fuel injection pump, since the thrust washer is interposed between the flange portion and the non-rotating portion of the drive shaft, the thrust washer receives the thrust load while sliding as the drive shaft rotates. However, when the pressure of the plunger that reciprocates in the rotor increases, the thrust load increases and the oil film on the surface of the thrust washer is pushed out of the thrust washer, causing insufficient lubrication on the surface of the thrust washer and causing rotation. There was a risk of defects.

Therefore, the present invention has been made in view of the above points, and it is an object of the present invention to secure an oil film on the surface of the thrust washer to prevent the rotor from rotating poorly.

[0008]

The invention according to claim 1 is
A drive shaft that is rotationally driven, a rotor that rotates together with the drive shaft and supplies pressurized fuel to the fuel injection nozzle, a flange portion that protrudes in the radial direction from the drive shaft or the rotor, and the flange portion. A fuel injection pump having a sliding member interposed between a sliding portion and a rotating portion for receiving a thrust load of the collar portion while sliding in a rotation direction of the drive shaft, and an oil film holding device for holding an oil film on a sliding surface of the sliding member. It is characterized in that a section is provided.

Further, the invention of claim 2 is characterized in that the oil film holding portion is a groove formed in the sliding surface of the sliding member and curved in the radial direction.

Further, the invention of claim 3 is characterized in that the oil film holding portion is made of a porous material which adsorbs oil.

According to a fourth aspect of the present invention, a drive shaft that is rotationally driven, a rotor that rotates together with the drive shaft and supplies pressurized fuel to a fuel injection nozzle, and the drive shaft or a radial direction from the rotor. A flange portion that protrudes in the direction of rotation, and a rotating body that is fitted and fixed to the outer periphery of the flange portion and whose rotation is detected by a rotation detection sensor,
A fuel injection pump having a sliding member interposed between the collar portion and the non-rotating portion and receiving a thrust load of the collar portion while sliding in the rotation direction of the drive shaft, wherein an end face of the rotating body is the collar portion. It is formed so as to be flush with the end face of, and the sliding member is interposed between the end face of the flange portion and the rotating body and the non-rotating portion.

According to a fifth aspect of the invention, a drive shaft that is rotationally driven, a rotor that rotates together with the drive shaft to supply pressurized fuel to a fuel injection nozzle, and the drive shaft or a radial direction from the rotor. A flange portion that protrudes in the direction of rotation, and a rotating body that is fitted and fixed to the outer periphery of the flange portion and whose rotation is detected by a rotation detection sensor,
A sliding member that is interposed between the collar portion and the non-rotating portion and receives a thrust load of the collar portion while sliding in the rotation direction of the drive shaft, and the rotating body is provided on an outer peripheral step portion of the collar portion. After fitting, the end face of the flange portion and the end face of the rotating body are cut so that they are flush with each other, and then the sliding member is attached to the end face of the flange portion and the rotating body and the non-rotating portion. It is characterized in that it is interposed between them.

[0013]

According to the invention of claim 1, since the oil film holding portion for holding the oil film is provided on the sliding surface of the sliding member interposed between the collar portion and the non-rotating portion, the sliding member and the non-rotating portion are provided. It prevents the oil film from being held between the parts and causing insufficient lubrication.

According to the second aspect of the invention, since the oil film holding portion is a groove formed on the sliding surface of the sliding member and curved in the radial direction, the oil film attached to the sliding surface of the sliding member is the groove. The oil filled in is prevented from flowing out of the sliding member.

Further, according to the third aspect of the invention, since the oil film holding portion is made of a porous material that adsorbs oil, the oil adsorbed by the porous material is supplied to the sliding surface of the sliding member, resulting in insufficient lubrication. Is prevented.

Further, according to the invention of claim 4, the end face of the flange portion projecting in the radial direction from the drive shaft, and the end face of the rotating body fitted and fixed to the outer periphery of the flange portion and rotationally detected by the rotation detecting sensor. Are formed so as to be flush with each other, and the sliding member is interposed between the flange portion and the end surface of the rotating body and the non-rotating portion, so that the sliding member has a large diameter to the same extent as the outer diameter of the rotating body. It is possible to increase the area in contact with the rotating portion.

Further, according to the invention of claim 5, the rotating body is fitted to the outer peripheral step portion of the flange portion, and thereafter, cutting is performed so that the end surface of the flange portion and the end surface of the rotating body are flush with each other. This makes it possible to finish the end surface of the flange portion and the end surface of the rotating body with high accuracy.

[0018]

FIG. 1 shows a first embodiment of the fuel injection pump of the present invention.

In the figure, a housing 11 is a main body of the fuel injection pump 10, and inside thereof, a fuel chamber 12 for accommodating each functional component of the fuel injection pump 10 and filled with fuel is provided.

Further, the overflow valve 2 which communicates with a predetermined position of the fuel chamber 12 is provided in the housing 11.
0, a spill valve 30, a fuel recirculation valve 40, an accumulator 50, and a constant pressure valve 60.

The overflow valve 20 is provided in the fuel chamber 12
The valve is a valve that prevents the internal pressure from becoming excessive, and is provided with a check valve including a ball valve 22 and a spring 24. When the fuel is excessively supplied into the fuel chamber 12, the excessive amount is supplied to the fuel tank ( Reflux (not shown). In this embodiment, the valve opening pressure is set to about 0.8 kg / cm ² .

The spill valve 30 is an electromagnetic valve that opens and closes the valve element 32 by the electromagnetic force generated by the electromagnetic coil 31.
A fuel recirculation valve 40 and a fuel intake gallery 17 described later.
And controlling electrical connection with a fuel leakage passage 103 described later.

The valve body 32 of the spill valve 30 is urged upward by a spring 33, and its upper end is urged by a rod 34 for transmitting the electromagnetic force generated by the electromagnetic coil 31 and a spring 35. Stopper 3
It is regulated by 6.

On the other hand, the valve body 32 and its valve seat 37 are
When 2 is seated on the valve seat 37, that is, when the spill valve 30 is closed, hydraulic pressure acts only on the side surface of the valve body 32, and the valve body 32 separates from the valve seat 37. When the spill valve 30 is open, the hydraulic pressure is also applied to the tip of the valve element 32.

That is, when the electromagnetic coil 31 generates an electromagnetic force and the rod 34 presses the valve body 32, the pressing force of the rod 34 and the urging force of the spring 35 act on the valve body 32 in the valve closing direction. As a result, the valve body 32 is displaced against the biasing force of the spring 33, and the spill valve 30 is closed.

When the pressing force of the rod 34 disappears, the urging force of the spring 33 displaces the valve body 32 in the valve opening direction against the urging force of the spring 35, and the spill valve 30 is opened. At this time, since a hydraulic pressure that presses the valve body 32 in the valve opening direction acts on the tip of the valve body 32, the higher the hydraulic pressure is, the greater the degree of opening of the spill valve 30 is secured.

The fuel recirculation valve 40 is the spill valve 30.
This valve is provided to appropriately depressurize the fuel leaked from the fuel leak passage when the valve is opened and to recirculate it to the fuel tank. Like the overflow valve 20 described above, it is a reverse valve including a ball valve 42 and a spring 44. It consists of a stop valve.

Further, the accumulator 50 is arranged to absorb the pulsation of the fuel pressure in the fuel intake gallery 17, and the piston 52 is displaced according to the pressure fluctuation of the fuel chamber communicating with the fuel intake gallery 17. , And a spring 54 for urging the piston 52.

The constant pressure valve 60 is a valve provided between the fuel outflow port 102 in the housing 11 described later and the fuel injection valve provided in each cylinder of the internal combustion engine. When the pressure exceeds a predetermined pressure and becomes high, the fuel flows toward the fuel injection valve at that pressure, and the fuel outflow port 10
It has a function of keeping the pressure on the fuel injection valve side at a predetermined pressure even when the internal pressure of 2 becomes equal to or lower than the predetermined pressure.

Further, in the fuel chamber 12 of the housing 11,
A drive shaft 70 that rotates at half the rotational speed of a crankshaft of an internal combustion engine, and a vane fuel feed pump (hereinafter simply referred to as a feed pump) 80 that feeds fuel using the rotational force of the drive shaft 70 as a drive source. , Drive shaft 70
A rotor 90 that rotates together with the rotor 90, a cylinder 100 into which the small diameter portion of the rotor 90 is inserted, and a cam ring 110 that surrounds the outer periphery of the large diameter portion of the rotor 90 are incorporated.

The drive shaft 70 is rotatably held with respect to the housing 11 by a bush 13 provided near the end of the housing 11 and a bearing 14 provided inside the housing 11. Where bush 13
In order to reduce the sliding resistance, fuel is supplied, and an oil seal 18 is provided at the end portion thereof, and an oil passage 16 is provided to connect the fuel inlet 15 and the bush 13. .

Here, a pulsar 120 having a plurality of protrusions 121 provided at predetermined intervals on the outer circumference of the drive shaft 70 is fitted and inserted, while the cam ring 110 rotates together with the drive shaft 70. Protrusion 1 of pulsar 120
A rotation angle sensor 122 for converting the proximity / separation of 21 into a pulse signal is fixed.

The drive shaft 70 and the rotor 90 are connected to each other, and the rotation of the drive shaft 70 is transmitted to the rotor 90. Therefore, the rotor 90 rotates integrally with the drive shaft 70.

In the fuel injection pump 10 having the above structure, the rotation angle of the drive shaft 70 with respect to the cam ring 110, that is, the rotation angle of the rotor 90 with respect to the cam ring 110 is detected by counting the number of pulses emitted by the rotation angle sensor 122. Is possible.

The feed pump 80 is a vane type pump having an outer wall 81 fixed to the housing 11 and a rotor 83 having a plurality of vanes 82. That is, the fuel sucked from the suction port 84 provided in communication with the fuel inlet 15 is pressurized by the vanes 82 as the rotor 83 rotates and is discharged from the fuel discharge port 85 provided at a predetermined position. .

Further, the drive shaft 70 is provided with a flange portion 70a protruding in the radial direction. And the collar portion 70a
There is a pulsar (rotating body) on the step 70b provided on the outer periphery of the
120 is fixedly fitted.

Further, the collar portion 70a and the feed pump 80
A thrust washer (sliding member) 87 is interposed between the side wall (non-rotating portion) 86 of the. The thrust washer 87 receives a thrust load acting on the drive shaft 70 in the axial direction (X direction) and rotates in the same direction as the drive shaft 70 rotates. That is, the thrust washer 87
Receives a thrust load while rotating at a lower rotation speed than the drive shaft 70.

Between the drive shaft 70 and the rotor 90,
Although the spring 71 is interposed and urges the measuring members in the direction in which they are separated from each other, when a thrust load larger than the spring force of the spring 71 is generated, the drive shaft 70 is pressed by the rotor 90.

Further, between the collar portion 70a and the thrust washer 87, and between the thrust washer 87 and the feed pump 80.
The fuel (light oil) in the fuel chamber 12 is supplied as a lubricating oil to the side wall 86. Therefore, an oil film of fuel is formed on the surface of the thrust washer 87.

The rotor 90, which is coupled to the drive shaft 70, is rotatably fitted in the cylinder hole 100a of the cylinder 100. Therefore, the cylinder hole 100a also functions as a bearing that rotatably supports the rotor 90.

Here, the rotor 90 has a pump chamber 91 in its large diameter portion, and a first fuel passage 94 for communicating a fuel inlet 92 and a fuel outlet 93 in its small diameter portion, and a fuel inlet 92. And a second fuel passage 95 communicating with the pump chamber 91.

Further, a plurality of plungers (four in this embodiment) 96a to 96d which can slide in the radial direction of the rotor 90 are inserted in the pump chamber 91. Further, the fuel discharge port 93 is communicated with an annular groove 97 provided around the outer circumference of the rotor 90 at a position offset in the axial direction.

On the other hand, the cylinder 100 is provided with a fuel supply port 101 for communicating the fuel suction gallery 17 communicating with the fuel discharge port 85 of the feed pump 80 via an external pipe (not shown) and the inner circumference of the cylinder 100. A plurality of fuel outflow ports 102, one end of which communicates with the constant pressure valve 60 on the outer circumference thereof and the other end of which opens to the inner circumference of the cylinder 100, are provided.

Here, each fuel intake port 101 is a port provided corresponding to each cylinder of the internal combustion engine, and when the rotor 90 rotates in synchronization with the rotation angle of the internal combustion engine, Fuel intake gallery corresponding to the rotation angle 1
7 is communicated with the fuel intake port 92 of the rotor 90, and the fuel discharge port 93 is communicated with the constant pressure valve 60 arranged in the specific cylinder.

The cylinder 100 is provided with a leak passage 103 for communicating the annular groove 97 provided in the rotor 90 with the spill valve 30. Here, the annular groove 97 is
As described above, the groove is provided over the entire circumference of the rotor 90. Therefore, the annular groove 97 and the spill valve 30 are always in communication with each other regardless of the rotation angle of the rotor 90.

The configuration around the pump chamber 91 will be described below with reference to FIG. 2 corresponding to the II-II section in FIG.
That is, the fuel injection pump 10 according to the present embodiment includes the rotor 9
This is a pump that boosts the pressure of fuel by driving four plungers 96a to 96d inserted in 0 with cams provided on the cam ring 110.

Here, the fuel pump 10 of this embodiment has six
Since it corresponds to a cylinder type internal combustion engine, the cam ring 110 has six cams 11 at equal intervals as shown in FIG.
0a to 110f are provided, and the four plungers 96a to 96d are all the plungers 96a to 96d.
Its position is designed so that there is a simultaneous lift on d. That is, the plungers 96a to 96d are attached to the cam 11
0a to 110f, a compression stroke of sliding toward the central axis of the rotor 90 is performed when passing through the cams 110a to 110f.
After passing f, a suction stroke of sliding toward the outside of the rotor 90 is performed.

The cams 110a to 110 of the cam ring 110 are provided at the outer peripheral side end portions of the plungers 96a to 96d.
In order to smoothly transmit the cam lift given by f to the plungers 96a to 96d, the roller shoes 98a to 9a
8d and rollers 99a to 99d held by the roller shoes 98a to 98d are provided. These plungers 96a to 96d, roller shoes 98a to 98d,
The cam surfaces of the rollers 99a to 99d and the cams 110a to 110f are lubricated with fuel (light oil). still,
The roller shoes 98a to 98d have a quadrangular cross-sectional shape to prevent rotation.

Inside the cam ring 110, the rotor 90
When the rotor 90 rotates, the plungers 96a to 96d make six reciprocating motions. When the reciprocating motion pressurizes the fuel in the pump chamber 91, the rotor 90 makes one revolution. During this period, that is, while the internal combustion engine makes two revolutions, the fuel pressure is increased six times for each equal rotation angle.

At this time, the fuel supply port 101 shown in FIG.
The fuel intake port 92 and the fuel intake port 92 communicate with each other under the condition that no cam lift is applied to the plungers 96a to 96d. Further, the fuel outflow port 102 and the fuel discharge port 9
3 is configured to communicate with the plungers 96a to 96d immediately before the lift occurs.

Therefore, when one of the fuel supply ports 101 and the fuel suction port 92 communicates with each other as the rotor 90 rotates, centrifugal force and fuel pressure supplied from the feed pump 80 are applied to the plungers 96a to 96d. As a result, the fuel is sucked into the pump chamber 91.

Then, when the communication between the fuel supply port 101 and the fuel suction port 92 is cut off, and then the lift is generated in the plungers 96a to 96d in the state where the fuel outflow port 102 and the fuel discharge port 93 are communicated, the spill valve 3
Assuming that 0 is closed, high-pressure fuel is supplied to the constant pressure valve 60.

By the way, when the pressure of the fuel is increased by the plungers 96a to 96d, the spill valve 30 described above is used.
When the valve is open, the fuel pressure-fed from the pump chamber 91 flows back to the fuel tank or the like via the spill valve 30, and high-pressure fuel is not supplied to each cylinder.

That is, assuming that the spill valve 30 does not exist, the fuel injection timing for each cylinder is uniquely determined by the cam profile provided on the cam ring 110, and the degree of freedom regarding fuel injection timing control is significantly lost. It will be in a state of being

On the other hand, in the structure having the spill valve 30 as in the present embodiment, even if the pressure increase in the pump chamber 91 is started, the fuel injection is not performed as long as the spill valve 30 is opened as described above. In this sense, the fuel injection start timing is controlled by controlling the timing of switching the spill valve 30 from the open state to the closed state, and the fuel injection end timing is controlled by controlling the timing of opening the spill valve 30 again. It is possible to control with high precision.

In this embodiment, the rotor 90 has an annular groove 97.
And the fuel leak passage 103 is provided in the cylinder 100,
Further, the spill valve 30 for controlling the conduction of the fuel leakage passage 103 is provided in order to realize the fuel injection timing control as described above.

In this case, in order to control the fuel injection end timing with high accuracy, it is more advantageous that the leakage capability when the spill valve 30 is opened is higher.

When leaking the high-pressure fuel using the spill valve 30, the first and second passages 9 provided in the rotor 90 are caused by the inertial effect of the fuel at the time of the leak.
The internal pressure of 4, 95 may become negative. When the internal pressure in these passages becomes negative, the plungers 96a-9a
The relationship of the amount of fuel pumped with respect to the stroke of 6d changes, and the control accuracy of the fuel injection amount deteriorates.

In the present embodiment, a part of the fuel leaked through the spill valve 30 is returned to the fuel intake gallery 17, and the accumulator 50 is provided in communication with the fuel intake gallery 17 to prevent such an adverse effect. This is for effective removal.

That is, the fuel injection pump 10 of this embodiment.
In the above, since the configuration as described above is adopted,
Even if excessive fuel leaks due to the inertial effect at the time of fuel leak, a part of it acts to increase the internal pressure of the fuel intake gallery 17, and the pulsation of the internal pressure due to the recirculation of the leaked fuel causes accumulator 50. Since it is appropriately absorbed by, it is possible to stably inject a sufficient amount of fuel at the time of the next fuel intake.

Further, the fuel injection pump 10 of this embodiment is
A timer device 130 for changing the fixed angle of the cam ring 110 with respect to the housing 11 is provided. That is, the cam ring 110 is rotatably assembled to the howling 11, and is further fixed to a rod 133 sandwiched between timer pistons 131 and 132, as shown in FIG.

Here, the timer pistons 131 and 132
2 is a piston slidably inserted into the timer device 130. In FIG. 2, a high pressure chamber 134 communicating with the fuel discharge port 85 of the feed pump 80 is provided on the right side of the timer piston 131. On the left side of 132, the low pressure chamber 1 communicating with the fuel intake port 84 of the feed pump 80.
35 are formed respectively.

A spring 136 for urging the timer piston 132 to the right in FIG. 2 is arranged in the low pressure chamber 135, and the high pressure chamber 134 and the low pressure chamber 135 are electrically connected by the solenoid valve 140 shown in FIG. Are connected by external pipes that are controlled. In this case, the high pressure chamber 134 and the low pressure chamber 135
The cam ring 110 rotates in accordance with the pressure difference between and, and in this embodiment, the opening / closing valve of the solenoid valve 140 is duty-controlled to control the rotation angle to a desired value.

With this structure, the plunger 9 with respect to the rotation angle of the rotor 90, that is, the rotation angle of the internal combustion engine.
It is possible to change the lift characteristics of 6a to 96d, so that it is possible to further increase the degree of freedom regarding fuel injection timing control, and a fuel injection pump with excellent controllability is realized.

Next, the structure of the main part of the present invention will be described with reference to FIG.

In FIG. 3, the thrust washer 87 is formed in a hollow disk shape, and the front surface 87a and the rear surface 87b are sliding surfaces. Front face 87a of thrust washer 87
A spiral groove 88 is formed on the rear surface 87b. In this embodiment, the six grooves 88 (88a
~ 88f) are formed at intervals of 60 °. Each groove 88
(88a to 88f) are curved so that the front surface 87a and the rear surface 87b have the same direction.

The thrust washer 87 rotates in the same direction (direction A) as the drive shaft 70 rotates. At that time, the front surface 87a and the rear surface 87b of the thrust washer 87 are
The oil film formed on the surface of the oil starts moving from the inside to the outside due to the centrifugal force.

However, the fuel as the lubricating oil is supplied to each groove 88.
Each groove 88 (88a-88f) from the outer peripheral side opening of (88a-88f)
Up to 88f) in the B direction, and this prevents the oil film formed on the surfaces of the front surface 87a and the rear surface 87b from moving outside the spiral groove 88. Therefore, in this embodiment, the grooves 88 (88a to 88) are formed.
f) functions as an oil film holding means.

Therefore, the front face 8 of the thrust washer 87 is
An oil film is always formed on the surfaces of 7a and the rear surface 87b, and is formed between the collar portion 70a and the thrust washer 87, and between the thrust washer 87 and the side wall 86 of the feed pump 80.
It is prevented that the lubrication between and becomes insufficient. As a result, when the fuel is pressurized to a high pressure by the reciprocating motion of the plungers 96a to 96d, the thrust force of the rotor 90 pressing the drive shaft 70 increases, but the thrust washer 8
An oil film is held on the surfaces of the front surface 87a and the rear surface 87b of No. 7.

Therefore, even if the thrust load is applied to the collar portion 70a of the drive shaft 70, the thrust washer 87 is provided with the collar portion 70a.
It is possible to smoothly rotate and slide between a and the side wall 86 of the feed pump 80, and the drive shaft 70 and the rotor 90 can rotate stably.

The number of the grooves 88 (88a to 88f) and the curvature to be curved are arbitrarily set according to the rotational speeds of the drive shaft 70 and the rotor 90, the pressure generated by the compression process, and the like.

FIG. 4 shows a second embodiment of the present invention.

In the figure, the thrust washer 89 is made of a porous material (for example, sintered metal) and has a front surface 89.
Innumerable minute holes are provided on the surfaces of a and the rear surface 89b. Therefore, fuel as lubricating oil is adsorbed on the surfaces of the front surface 89a and the rear surface 89b. Therefore, in this embodiment, the porous material containing the fuel functions as the oil film holding means.

Then, the thrust washer 89 is attached to the collar portion 70.
When a thrust load is applied between a and the side wall 86 of the feed pump 80, the fuel adsorbed by the porous material is transferred to the front surface 8.
The oil film is retained by exuding to the surfaces of 9a and the rear surface 89b.

Therefore, even if the thrust load acts on the collar portion 70a of the drive shaft 70, the thrust washer 89 keeps the collar portion 70a.
It is possible to smoothly rotate and slide between a and the side wall 86 of the feed pump 80, and the drive shaft 70 and the rotor 90 can rotate stably.

Further, in this embodiment, the thrust washer 89
Although the whole is made of the porous material, the present invention is not limited to this, and at least only the portion slidingly contacting the flange portion 70a of the drive shaft 70 and the side wall 86 of the feed pump 80 may be made of the porous material. .

5 to 7 show the manufacturing process of the third embodiment.

In FIG. 5, a pulsar 120 is formed annularly on a step portion 70b provided on the outer periphery of the collar portion 70a of the drive shaft 70.
Fit and fix. The relationship between the axial thickness of the pulsar 120 and the axial dimension of the step portion 70b varies depending on manufacturing errors. However, as shown in FIG. 5, the axial thickness dimension of the pulsar 120 is equal to the step portion. If the dimension L is larger than the axial dimension of 70b, the side surface of the pulsar 120 has a step 70b.
Stick out more.

Next, as shown in FIG. 6, the end surface 70c of the collar portion 70a and the end surface 120a of the pulsar 120 are cut so as to be flush with each other by using, for example, a lathe. As a result, the side surface of the pulsar 120 protruding from the step 70b in the axial direction (X direction) is cut. At this time, the end surface 70c of the collar portion 70a is also cut at the same time, so that the end surface 70c of the collar portion 70a and the end surface 120a of the pulsar 120 can be made into a single flat surface without a step.

Therefore, as described above, the collar portion 7 of the drive shaft 70 is
It is better to process with the pulsar 120 fitted to 0a.
The end surface 70c of the collar portion 70a and the end surface 120a of the pulsar 120
It can be machined with higher precision than if the and are machined separately, and it is as if the end face 70c of the collar portion 70a.
The end surface 120a of the pulsar 120 and the pulsar 120 can be machined with the same degree of accuracy as an integrated body.

Next, as shown in FIG. 7, the housing 11 with the drive shaft 70 inserted into the thrust washer 87 is inserted.
When assembled in, the thrust washer 87 is interposed between the collar portion 70a and the side wall 86 of the feed pump 80. In the present embodiment, as described above, the end surface 70c of the collar portion 70a and the end surface 120a of the pulsar 120 are processed into a single flat surface without a step, so that the outer diameter of the thrust washer 87 is the same as the outer diameter of the pulsar 120. It can be increased to a degree.

Therefore, the front face 8 of the thrust washer 87 is
7a is in sliding contact with the side wall 86 of the feed pump 80, and the rear surface 87b of the thrust washer 87 is the end surface 70c of the collar portion 70a.
And slidably contact the end surface 120a of the pulsar 120. Therefore,
The thrust washer 87 is an end surface 120 a of the pulsar 120.
Since the sliding contact area can be increased, the sliding contact area can be increased and a larger thrust load can be received.

Therefore, the rotor 90 has the plungers 96a ...
Even if the drive shaft 70 is pressed in the axial direction (X direction) by the high pressure generated by the compression operation of 96d and the drive shaft 70 is pressed in the same direction, the sliding contact area of the thrust washer 87 is increased. The contact pressure is reduced, the oil film breakage is reduced, and the oil film is retained.

Although the thrust washer 87 of the first embodiment described above is used in this embodiment, the present invention is not limited to this, and the thrust washer 89 of the second embodiment may be used.

In each of the above embodiments, the hollow disk-shaped thrust washer 87 or 89 is interposed between the flange portion 70a of the drive shaft 70 and the side wall 86 of the feed pump 80. Of course, the present invention can also be applied to a configuration using a sliding member having a shape other than the above (for example, one having a polygonal outer periphery).

[0086]

As described above, according to the invention of claim 1, the oil film holding portion for holding the oil film is provided on the sliding surface of the sliding member interposed between the collar portion and the non-rotating portion. Even if the pressure due to the fuel pressurizing operation of the rotor acts in the axial direction between the sliding member and the non-rotating portion, it is possible to prevent the oil film from running out on the sliding surface of the sliding member. Therefore, it is possible to prevent the oil film from being held on the sliding surface of the sliding member to cause insufficient lubrication, and it is possible to rotate the drive shaft and the rotor stably and smoothly.

According to the second aspect of the invention, since the oil film holding portion is a groove formed on the sliding surface of the sliding member and curved in the radial direction, the oil film attached to the sliding surface of the sliding member is the groove. It is possible to prevent the oil filled in the oil from flowing out of the sliding member. Therefore, it is possible to prevent the oil film from being held on the sliding surface of the sliding member to cause insufficient lubrication, and it is possible to rotate the drive shaft and the rotor stably and smoothly.

According to the third aspect of the invention, since the oil film holding portion is made of a porous material that adsorbs oil, the oil adsorbed by the porous material is supplied to the sliding surface of the sliding member, and the sliding member is supplied. The oil film on the sliding surface of can be held. Therefore, insufficient lubrication of the sliding member can be prevented, and the drive shaft and the rotor can be rotated stably and smoothly.

Further, according to the invention of claim 4, the end face of the flange portion that projects in the radial direction from the drive shaft, and the end face of the rotating body that is fitted and fixed to the outer periphery of the flange portion and whose rotation is detected by the rotation detection sensor are provided. Are formed so that they are flush with each other, and the sliding member is interposed between the flange portion and the end surface of the rotating body and the non-rotating portion,
The sliding member can be made as large as the outer diameter of the rotating body to increase the area in contact with the non-rotating portion, thereby reducing the pressure per unit area of the sliding surface of the sliding member to reduce the sliding surface. It is possible to prevent the oil film from running out.

Further, according to the invention of claim 5, the rotating body is fitted to the outer peripheral step portion of the flange portion, and thereafter, cutting is performed so that the end surface of the flange portion and the end surface of the rotating body are flush with each other. This makes it possible to finish the end surface of the collar portion and the end surface of the rotating body with high accuracy. Therefore, the sliding member can be made as large as the outer diameter of the rotating body to increase the area in contact with the non-rotating portion, which reduces the pressure per unit area of the sliding surface of the sliding member and reduces the sliding force. It is possible to prevent the oil film from running out on the moving surface.

[Brief description of drawings]

FIG. 1 is a front sectional view showing the overall configuration of a first embodiment of a fuel injection pump according to the present invention.

FIG. 2 is a side sectional view showing a configuration around a pump chamber of a fuel injection pump.

FIG. 3 is an enlarged vertical cross-sectional view of the thrust washer of the first embodiment.

FIG. 4 is an enlarged vertical sectional view of a thrust washer of a second embodiment.

FIG. 5 is a process drawing for explaining the manufacturing process for the third embodiment.

FIG. 6 is a process diagram of a cutting process performed following FIG.

FIG. 7 is a diagram after assembly performed after the cutting process shown in FIG. 6;

[Explanation of symbols]

 10 Fuel injection pump 20 Overflow valve 30 Spill valve 40 Fuel recirculation valve 50 Accumulator 60 Constant pressure valve 70 Drive shaft 70a Collar portion 80 Feed pump 87,89 Thrust washer 90 Rotor 91 Pump chamber 96 (96a to 96d) Plunger 98 (98a to 98d) ) Roller shoe 99 (99a to 99d) Roller 100 Cylinder 120 Pulser

Claims (5)

[Claims] 1. A drive shaft that is rotationally driven, a rotor that rotates together with the drive shaft and supplies pressurized fuel to a fuel injection nozzle, and a flange portion that projects radially from the drive shaft or the rotor. A fuel injection pump having a sliding member interposed between the flange portion and a non-rotating portion and receiving a thrust load of the flange portion while sliding in the rotation direction of the drive shaft, wherein an oil film is formed on a sliding surface of the sliding member. A fuel injection pump comprising an oil film holding portion for holding the fuel injection pump. 2. The fuel injection pump according to claim 1, wherein the oil film holding portion is a groove formed in a sliding surface of the sliding member and curved in a radial direction. 3. The fuel injection pump according to claim 1, wherein the oil film holding portion is made of a porous material that adsorbs oil. 4. A drive shaft that is rotationally driven, a rotor that rotates together with the drive shaft and supplies pressurized fuel to a fuel injection nozzle, and a flange portion that projects radially from the drive shaft or the rotor. A rotating body that is fitted and fixed to the outer periphery of the collar portion and is rotated and detected by a rotation detection sensor, and is interposed between the collar portion and the non-rotating portion, and the thrust load of the collar portion while sliding in the rotation direction of the drive shaft. And a sliding member for receiving the sliding member, the end surface of the rotating body being formed to be flush with the end surface of the collar portion, and the sliding member including the flange portion and the end surface of the rotating body. A fuel injection pump characterized by being interposed between a rotating part and a rotating part. 5. A drive shaft that is rotationally driven, a rotor that rotates together with the drive shaft and supplies pressurized fuel to a fuel injection nozzle, and a flange portion that projects radially from the drive shaft or the rotor. A rotating body that is fitted and fixed to the outer periphery of the collar portion and is rotated and detected by a rotation detection sensor, and is interposed between the collar portion and the non-rotating portion, and the thrust load of the collar portion while sliding in the rotation direction of the drive shaft. And a sliding member for receiving the rotary member, and the rotary member is fitted to the outer peripheral step portion of the flange portion, and then subjected to cutting processing so that the end surface of the flange portion and the end surface of the rotary member are flush with each other. Then, the method of manufacturing a fuel injection pump, characterized in that the sliding member is interposed between the flange portion and the end surfaces of the rotating body and the non-rotating portion.