JPH0942101A - Distributor type fuel injection pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a distributor type fuel injection pump with a fuel force feeding passage characterized by small pressure loss and to be miniaturized. SOLUTION: A fuel suction opening 27 and a fuel discharge opening 28 are formed in a peripheral wall of a distribution rotor 13, and the fuel discharge opening 28 is formed at a position farther from a fuel pressurizing chamber than the fuel suction opening 27 in the axial direction. A first fuel passage 25 connects the fuel pressurizing chamber and the fuel suction opening 27. As the position moves from the fuel suction opening 27 toward the fuel discharge opening 28, a second fuel passage 26 gradually parts from a virtual plane, which contains both fuel pressurizing chamber and fuel suction opening 27 and which passes through a rotation axis of the distribution rotor 13, and extends toward the direction of rotation of the distribution rotor 13. A distribution passage 30 is formed in such a manner that its extension (line) deviates from the rotation axis of the distribution rotor 13. As a result, the curvature of a flow of the fuel, which is led to the distribution passage 30 from the second fuel passage 26 via the fuel discharge opening 28, becomes smaller. Therefore, the pressure loss becomes smaller.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine (hereinafter referred to as "internal combustion engine").
The present invention relates to a distributed fuel injection pump for an "internal combustion engine".

[0002]

2. Description of the Related Art Conventionally, an inner cam type fuel injection pump has been known as a fuel injection pump for a diesel engine, for example. The inner cam type fuel injection pump has an inner cam ring arranged on the outer periphery of a distribution rotor rotatably supported by a cylinder, and a plunger accommodated in the distribution rotor reciprocates in the radial direction of the distribution rotor along the cam surface of the inner cam ring. By moving, the fuel sucked into the fuel pressurizing chamber is pressurized to be pumped and distributed.

The main parts of such an inner cam type fuel injection pump are shown in FIGS. 8 and 9. The distribution rotor 120 is rotatably supported by the cylinder 121, and
The plunger 122 is housed so as to be capable of reciprocating in the radial direction. An inner cam ring 123 is arranged on the outer periphery of the distribution rotor 120 surrounding the plunger 122. A fuel passage 125 communicating with the fuel pressurizing chamber 124 is formed substantially in the center of the distribution rotor 120.
An intake passage 126 and a discharge passage 127 that communicate vertically with the fuel passage 125 are formed in a planar shape including 25.
A fuel discharge port 128 communicating with the discharge passage 127 is formed on the outer wall of the distribution rotor 120.
With the rotation of 0, it communicates with the distribution passage 129 formed in the cylinder 121. Fuel discharge port 128 in the pressure stroke
And the distribution passage 129 communicate with each other, the high-pressure fuel pressurized in the fuel pressurizing chamber 124 receives the fuel passage 127 and the fuel discharge port 1.
28, and is pressure-fed through the distribution passage 129.

[0004]

However, in the fuel injection pump shown in FIGS. 8 and 9, since the suction passage 126 and the discharge passage 128 are individually formed in the distribution rotor 120, they are not directly involved in the fuel pumping. Due to the large dead volume, the fuel pumping efficiency is reduced. If the distribution rotor is increased in size to compensate for this decrease, there is a problem that the size of the fuel injection pump becomes large.

In order to solve this problem, in the distribution rotor 130 shown in FIG. 10, the first fuel passage 131 which communicates with the fuel pressurizing chamber 134 and also communicates with the second fuel passage 132 through the fuel suction port 133. Serves as both a fuel intake passage and a fuel discharge passage. Therefore, compared with the fuel injection pump shown in FIGS. 8 and 9, the dead volume formed in the distribution rotor 130 is reduced and the pumping efficiency is increased, so that the distribution rotor can be downsized.

However, the conventional example 1 shown in FIG. 8 and FIG.
In Conventional Example 2 shown in FIG. 10 and Taking Conventional Example 1 as an example, as shown in FIG. 9, depending on the rotational position of distribution rotor 120, the flow of fuel through discharge passage 127, fuel discharge port 128, and distribution passage 129 is Since the bend is large, there is a problem that the pressure loss increases. The present invention has been made to solve such a problem, and an object of the present invention is to provide a fuel injection pump which has a small pressure loss in the fuel pressure feeding system passage and can be miniaturized.

[0007]

According to a first aspect of the present invention, there is provided a fuel injection pump of the distribution type according to the first aspect of the present invention. What is claimed is: 1. A distribution type fuel injection pump that pressurizes and sucks and distributes fuel sucked into a pressure chamber, and a distribution rotor that rotates in synchronization with an engine and that supports a plunger so as to be capable of reciprocating in a radial direction. A fuel inlet is provided on the outer peripheral wall of the rotor, and a fuel outlet is provided on the outer peripheral wall of the distribution rotor axially farther from the fuel pressurizing chamber than the fuel inlet, and the fuel pressurizing chamber and the fuel inlet are provided. Fuel is supplied to the fuel pressurizing chamber via a first rotor which communicates with the first fuel passage and a second rotor which communicates with the fuel inlet and the fuel outlet, and a distribution rotor which has the second fuel passage. Available A suction passage and a cylinder that rotatably supports the distribution rotor by providing a distribution passage that can communicate with the fuel discharge port, and the second fuel passage extends from the fuel suction port to the fuel discharge port. It is characterized in that it extends toward a direction away from a virtual plane including the fuel intake port and the rotation axis of the distribution rotor.

According to the distribution type fuel injection pump of the first aspect, since the second fuel passage extends from the fuel intake port to the fuel discharge port in a direction away from the axial direction of the distribution rotor, the second fuel passage is provided in the pressure feeding stroke. The bending of the fuel flow flowing from the second fuel passage to the fuel discharge port can be reduced. For this reason,
Since the pressure loss of the fuel flowing from the second fuel passage to the fuel discharge port is reduced, the fuel pumping efficiency is increased.

A distribution type fuel injection pump according to a second aspect of the present invention is a distribution type fuel injection pump for pressurizing and feeding and distributing fuel sucked into a fuel pressurizing chamber by a plunger that reciprocates according to a cam profile. A distribution rotor that rotates in synchronism with an engine and supports a plunger so as to be capable of reciprocating in a radial direction, wherein a fuel intake port is provided on an outer peripheral wall of the distribution rotor and the fuel pressurization is performed from the fuel intake port. A fuel outlet on the outer peripheral wall of the distribution rotor axially distant from the chamber, and a first fuel passage that connects the fuel pressurizing chamber and the fuel inlet, and the fuel inlet and the fuel outlet. A distribution rotor having a second fuel passage communicating with the fuel supply port, a suction passage capable of supplying fuel to the fuel pressurizing chamber via the fuel suction port, and a distribution passage capable of communicating with the fuel discharge port. And a cylinder for rotatably supporting the distribution rotor, the extension of the dispensing passage, characterized in that the offset from the rotational axis of the dispensing rotor.

According to the distribution type fuel injection pump of the second aspect, since the extension line of the distribution passage is deviated from the rotation axis of the distribution rotor, the flow of the fuel flowing from the fuel discharge port to the distribution passage in the pressure stroke is bent. Can be made smaller. For this reason, the pressure loss of the fuel flowing from the fuel discharge port into the distribution passage is reduced, so that the fuel pumping efficiency is increased. A distribution type fuel injection pump according to a third aspect of the present invention is the distribution type fuel injection pump according to the second aspect, wherein the second fuel passage receives the fuel from the fuel suction port toward the fuel discharge port. It extends in a direction away from an imaginary plane including the mouth and the rotation axis of the distribution rotor.

According to the distribution type fuel injection pump of the third aspect, in addition to the structure of the fuel injection pump of the second aspect, a fuel intake port and a rotation shaft of the distribution rotor are provided from the fuel intake port toward the fuel discharge port. Since the second fuel passage extends in the direction away from the imaginary plane, the bend of the fuel flow flowing from the second fuel passage to the fuel discharge port in the pumping stroke and the fuel flow flowing from the fuel discharge port to the distribution passage The bend can be reduced. For this reason, the pressure loss of the fuel flowing from the second fuel passage to the distribution passage via the fuel discharge port is reduced, so that the fuel pumping efficiency is further increased.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIGS. 1 to 4 show an inner cam type distribution type fuel injection pump according to a first embodiment of the present invention. The distributed fuel injection pump (hereinafter referred to as “injection pump”) 10 is a four-cylinder injection pump.

As shown in FIG. 4, a drive shaft 1 of an injection pump 10 driven by an engine (not shown) is rotatably supported by a pump housing 4 via a bearing 2 and a journal 3. The vane feed pump 5 rotates together with the drive shaft 1, sucks and pressurizes the fuel sucked from a fuel tank (not shown), and delivers the fuel to the fuel gallery 14 through an external pipe (not shown). The fuel gallery 14 is formed by providing an annular recess in the inner wall of the distribution head 11.

A cylinder 12 is fixed to the inner wall of the distribution head 11, and a distribution rotor 13 is rotatably supported on the inner wall of the cylinder 12. The distribution rotor 13 is axially connected to the drive shaft 1 and rotates together with the drive shaft 1. An overflow valve 50, which is an electromagnetic valve, is arranged coaxially with the distribution rotor 13 on the side opposite to the drive shaft of the distribution rotor 13. Distribution rotor 13
Is formed with a pair of sliding holes orthogonal to each other, and a pair of plungers 20 are slidably supported in an oil-tight state on the inner wall of the distribution rotor 13 forming the sliding holes. The fuel pressurizing chamber 21 is defined by the inner end surface and the inner wall forming each sliding hole.

A shoe 2 is provided at the outer end of each plunger 20.
2 is provided, and the roller 23 is rotatably held by each shoe 22. An inner cam ring 24 having a cam surface having four cam ridges corresponding to the number of engine cylinders formed on the inner peripheral surface of the roller 23 is disposed on the inner peripheral surface of the roller 23. By sliding on the cam surface of the inner peripheral surface of the cam ring 24, the roller 23
Moves reciprocally in the radial direction of the inner cam ring 24 along the cam surface, and this reciprocating movement is transmitted to the plunger 20 via the shoe 22. The plunger 20 moves radially outward of the distribution rotor 13 to move the fuel pressurizing chamber 21.
And the fuel is sucked into the plunger chamber 21.
As the plunger 20 moves radially inward of the distribution rotor 13, the volume of the plunger chamber 21 decreases and the fuel is pressurized. The inner cam ring 24 is rotatably supported on the inner wall of the pump housing 4, and is provided with a timer device 70.
The rotation angle can be adjusted by. The timer device 70 rotates the inner cam ring 24 by the driving force of the solenoid valve 71 to advance or close the fuel injection timing.

As shown in FIGS. 2 and 3, the fuel suction port 27 and the fuel discharge port 28 are formed on the outer peripheral wall of the distribution rotor 13, and the fuel discharge port 28 pressurizes the fuel more than the fuel suction port 27. It is formed at a position distant from the chamber 21 in the axial direction. The first fuel passage 25 is formed on a straight line connecting the fuel pressurizing chamber 21 and the fuel intake port 27, and connects the fuel pressurizing chamber 21 and the fuel intake port 27. The second fuel passage 26 is formed on a straight line connecting the fuel suction port 27 and the fuel discharge port 28, and communicates with the fuel suction port 27 and the fuel discharge port 28. The overflow port 29 is annularly formed on the outer peripheral wall of the distribution rotor 13 and axially displaced from the fuel discharge port 28, and communicates with the overflow passage 32.

The first fuel passage 25 is formed on an imaginary plane that includes the fuel pressurizing chamber 21 and the fuel suction port 27 and passes through the rotation axis of the distribution rotor 13. The second fuel passage 26 is not included in this virtual plane, but extends away from the virtual plane as it goes from the fuel inlet 27 to the fuel outlet 28 and extends in the rotation direction of the distribution rotor 13. The fuel intake port 27 communicates with the intake port 15 as an intake passage as the distribution rotor 13 rotates. Fuel inlet 2
7 and the intake port 15 communicate with each other, the fuel gallery 14
The fuel filled in the suction port 15 and the suction port 2
7. The fuel can be sucked into the fuel pressurizing chamber 21 through the first fuel passage 25.

As shown in FIGS. 1 and 2, the fuel discharge port 28 extends from the end of the second fuel passage 26 along the outer peripheral wall of the distribution rotor 13 in the rotation direction of the distribution rotor 13. The distribution passage 30 communicates with the second fuel passage 26 in a substantially straight line depending on the rotational position of the distribution rotor 13 in the cross section taken along the line I-I of FIG.
It is formed so as to deviate from the rotation axis of. In other words, the distribution passage 30 is connected to the cylinder 12 from the fuel discharge port 28 side.
Toward the outer periphery of the distribution rotor 13 in the rotation direction of the distribution rotor 13. The distribution passage 30 is always in communication with a distribution passage 31 provided in the distribution head 11, and high-pressure fuel is supplied from the distribution passage 31 through a delivery valve 40 to an injector (not shown).

The overflow valve 50 is coaxially arranged at one end of the distribution rotor 13. When the energization of the overflow valve 50 is off, the valve member 51 lifts to open the overflow valve 50, and the high-pressure fuel in the overflow passage 32 is discharged into the fuel chamber 6 via the fuel passage 61. A pulsar 41 provided with protrusions at predetermined intervals is fitted on the outer peripheral wall of the drive shaft 1, and a rotation angle sensor 42 for converting the approach or separation of the pulsar 41 into a pulse signal is fixed to the inner cam ring 24. ing.
That is, by counting the number of pulses output by the rotation angle sensor 42, the drive shaft 1 for the inner cam ring 24 is
The rotation angle of the distribution rotor 13, that is, the rotation angle of the distribution rotor 13 with respect to the inner cam ring 24 can be detected.

The overflow valve 60 is provided for decompressing a part of the overflow fuel and returning it to the fuel chamber 6 when the overflow valve 50 is opened. The fuel chamber 6 and the overflow valve 60 are connected by a fuel passage 61. Next, the operation of the injection pump 10 will be described. (1) Intake stroke As shown on the left side of FIG. 5, when the cam lift amount decreases, the plunger 20 moves to the outside in the radial direction of the distribution rotor 13,
Since the volume of the fuel pressurizing chamber 21 increases, the pressure of the fuel pressurizing chamber 21 decreases. At this time, when the fuel suction port 15 and the fuel suction port 27 communicate with each other, the fuel filled in the fuel gallery 14 is sucked into the suction port 15, the fuel suction port 27, and the first suction port 27.
Is sucked into the fuel pressurizing chamber 21 through the fuel passage 25. The fuel discharge port 28 is closed by the inner wall of the cylinder 12. The overflow valve 50 is closed.

(2) Pumping stroke When the distribution rotor 13 further rotates, the fuel intake port 27 is closed by the inner wall of the cylinder 12. Cam roller 23
Rides on the cam ridge of the inner cam ring 24 and the plunger 20 starts to move inward in the radial direction.
The fuel inside is pressurized. At this time, the fuel discharge port 28 and the distribution passage 30 communicate with each other. When the fuel pressurized in the fuel pressurizing chamber 21 reaches a certain pressure or more, the delivery valve 40 opens, and the high pressure fuel in the fuel pressurizing chamber 21 becomes the first fuel passage 2
5, the fuel intake port 27, the second fuel passage 26, the fuel discharge port 28, the distribution passage 30, and the distribution passage 31, and the delivery valve 40 supplies the injector.

As shown in FIGS. 1 and 5, the fuel flow passing through the second fuel passage 26, the fuel discharge port 28, and the distribution passage 30 has a small bend in the fuel flow regardless of the rotational position of the distribution rotor 13. Further, depending on the rotation position of the distribution rotor 13, the fuel flows in a substantially linear communication. For this reason, the pressure loss of the fuel flowing from the second fuel passage 26 to the distribution passage 30 via the fuel discharge port 28 is reduced, so that the energy reduction of the fuel pumped from the fuel pressurizing chamber 21 by the plunger 20 is suppressed and the delivery is performed. Fuel can be pumped to the valve 40.

Further, from the fuel inlet 27 to the fuel outlet 28
Fuel inlet 27 and distributor rotor 1
And the distribution rotor 13 away from an imaginary plane containing the axis of rotation 3
Since the second fuel passage 26 extends in the rotation direction of the second fuel passage 26, the fuel in the second fuel passage 26 contains the plunger 20.
Accordingly, the rotational energy of the distribution rotor 13 is added to the pressure-fed energy that is pressure-fed from the fuel pressurizing chamber 21. For this reason,
The fuel supply capacity of the injection pump 10 increases.

(3) Overflow trend The rotational position θ of the distribution rotor 13 is detected by the number of pulses detected by each rotation sensor 42, and when the plunger 20 rises from BDC (bottom dead center) to a predetermined lift position, electromagnetic The solenoid valve 50 is opened by energizing the valve 50. Then, the overflow passage 32 and the fuel passage 61 communicate with each other, so that the high-pressure fuel in the fuel pressurizing chamber 21 receives the first fuel passage 25, the fuel suction port 27, the second fuel passage 26, the fuel discharge port 28,
It is overflowed into the low-pressure fuel chamber 6 through the overflow port 29, the overflow passage 32, and the fuel passage 61. If the fuel overflows, the distribution passage 3
The fuel pressure of No. 1 drops, and the fuel injection from the injector ends.

The above, (1) suction stroke, (2) pressure stroke, (3)
By repeating the overflow fashion, the fuel injection amount and fuel injection timing are controlled with high accuracy. (Second Embodiment) FIG. 6 shows an injection pump according to a second embodiment of the present invention.
Shown in A cylinder 82 is fixed to an inner wall of a distribution head 81 of the injection pump 80, and a distribution rotor 83 is rotatably supported on the inner wall of the cylinder 82.

The fuel intake port 88 and the fuel discharge port 89 are formed on the outer peripheral wall of the distribution rotor 83, and the fuel discharge port 8
8 is formed at a position farther from the fuel pressurizing chamber 21 in the axial direction than the fuel intake port 89. The first fuel passage 86 is formed on a straight line connecting the fuel pressurizing chamber 21 and the fuel intake port 88, and connects the fuel pressurizing chamber 21 and the fuel intake port 88.
The second fuel passage 87 has a fuel inlet 88 and a fuel outlet 89.
It is formed on a straight line connecting with and connects the fuel intake port 88 and the fuel discharge port 89. The annular fuel passage 90 is formed in the inner peripheral wall of the cylinder 82, and communicates with the fuel intake port 88 and the fuel passage 91 as an intake passage.

The first fuel passage 86 is formed on an imaginary plane that includes the fuel pressurizing chamber 21 and the fuel suction port 88 and passes through the rotation axis of the distribution rotor 83. The second fuel passage 87 is not included in this imaginary plane and extends away from the imaginary plane as it goes from the fuel inlet 88 to the fuel outlet 89 and extends in the rotation direction of the distribution rotor 83. The fuel discharge port 89 extends from the end of the second fuel passage 87 along the outer peripheral wall of the distribution rotor 83 in the rotation direction of the distribution rotor 83.

The distribution passage 92 extends from the fuel discharge port 89 side toward the outer periphery of the cylinder 82 in the rotation direction of the distribution rotor 83 and in the direction away from the fuel pressurizing chamber 21. That is, in the distribution passage 92, the extension line of the distribution passage 92 is the distribution rotor 8.
It is deviated from the rotation axis of No. 3, and is formed so as to communicate with the second fuel passage 87 in a substantially straight line depending on the rotation position of the distribution rotor 83.

The distribution passage 92 is always in communication with a distribution passage 93 provided in the distribution head 81, and high-pressure fuel is supplied from the distribution passage 93 to the injector (not shown) through the delivery valve 40. The overflow valve 100 is the distribution rotor 8
It is attached to the distribution head 81 from the direction perpendicular to the rotating shaft of No. 3, and closes when the energization of the electromagnetic coil 101 is turned on, and opens when the energization of the electromagnetic coil 101 is turned off.

Next, the operation of the injection pump 80 will be described. (1) Intake stroke The fuel is supplied to the fuel gallery 94 from the feed pump 5 through a fuel pipe (not shown), and the overflow fuel at the time of fuel overflow is recirculated from the overflow valve 100 as described later. The fuel supplied to the fuel gallery 94 is divided into two systems and reaches the fuel passage 104 of the overflow valve 100. One is a system that passes through the fuel passage 108 and the annular passage 107, and the other is a system that passes through the annular passage 103.

When the plunger 20 moves radially outward of the distribution rotor 83 and the volume of the fuel pressurizing chamber 21 increases, the pressure in the fuel pressurizing chamber 21 decreases. At this time, the overflow valve 100
Is opened, and the fuel passes through the fuel passage 104, the fuel passage 105, the fuel passage 106, the fuel passage 91, the fuel passage 90, the fuel suction port 88, and the first fuel passage 86, and the fuel is pressurized in the fuel pressurizing chamber 2.
Inhaled into 1. The fuel discharge port 89 is closed by the inner wall of the cylinder 82.

(2) Pressing stroke When the distribution rotor 83 further rotates, the cam roller 23 rides on the cam ridge of the inner cam ring 24 and the plunger 2
0 starts moving inward in the radial direction. At this time, the fuel discharge port 89 and the distribution passage 92 communicate with each other, and the electromagnetic coil 10
When the power to 1 is turned on and the overflow valve 100 is closed, the fuel in the fuel pressurizing chamber 21 is pressurized with the lift of the plunger 20. When this pressure exceeds a certain pressure, the delivery valve 40 opens, and the high pressure fuel in the fuel pressurizing chamber 21 becomes the first
Fuel passage 86, fuel inlet 88, second fuel passage 8
The fuel is supplied from the delivery valve 40 to the injector via the fuel discharge port 89, the distribution passage 92, and the distribution passage 93.

(3) Overflow trend When the electromagnetic coil 101 is turned off and the overflow valve 100 is opened during the pumping stroke, the overflow valve 100 is divided into two systems in the direction opposite to the fuel intake system path. Fuel overflows. The
By repeating (1) suction stroke, (2) pressure stroke, and (3) overflow stroke, highly accurate fuel injection amount and fuel injection timing control is performed.

Also in the second embodiment, as in the first embodiment, the second
Since the pressure loss at the time when the fuel passage 87, the fuel discharge port 89, and the distribution passage 92 communicate with each other is reduced, it is possible to suppress the reduction in the fuel pumping energy and supply the fuel to the delivery valve 40. Further, since the rotational energy of the distribution rotor 83 is added to the fuel pumping energy, the fuel supply capacity of the injection pump 80 increases.

With respect to the embodiment of the present invention described above, whether the distance from the fuel intake port to the fuel discharge port is away from the virtual plane including the fuel intake port and the rotation axis of the distribution rotor, and is the rotation direction of the distribution rotor? Alternatively, the present invention may have a configuration in which the extension line of the distribution passage formed in the cylinder with the second fuel passage extending in the counter-rotational direction of the distribution rotor passes through the rotation axis of the distribution rotor. It is also possible to form the second fuel passage on an imaginary plane including the fuel inlet and the rotation axis of the distribution rotor, with the extension line of the distribution passage formed in the cylinder being displaced from the rotation axis of the distribution rotor. Is.

[Brief description of drawings]

1 is a sectional view taken along line I-I of FIG. 2 showing a main part of an injection pump according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a main part of the injection pump according to the first embodiment of the present invention.

FIG. 3 is a perspective partial cross-sectional view showing a distribution rotor of the first embodiment.

FIG. 4 is a vertical sectional view showing an injection pump according to a first embodiment of the present invention.

FIG. 5 is a characteristic diagram showing a relationship between a distribution rotor rotation position, a cam lift amount, an angle sensor signal, a spill valve opening / closing, and a fuel injection pressure in the first embodiment.

FIG. 6 is a vertical sectional view showing an injection pump according to a second embodiment of the present invention.

FIG. 7 is a vertical cross-sectional view showing the main parts of the second embodiment.

FIG. 8 is a perspective sectional view showing a distribution rotor of Conventional Example 1.

FIG. 9 is a schematic diagram showing a discharged fuel flow of Conventional Example 1.

FIG. 10 is a perspective sectional view showing a distribution rotor of Conventional Example 2.

[Explanation of symbols]

 1 Drive Shaft 4 Vane Feed Pump 10 Injection Pump (Distribution Fuel Injection Pump) 12 Cylinder 13 Distribution Rotor 14 Fuel Gallery 15 Suction Port 20 Plunger 21 Fuel Pressurizing Chamber 24 Inner Cam Ring 25 First Fuel Passage 26 Second Fuel Passage 27 Fuel inlet 28 Fuel outlet 29 Overflow port 30, 31 Distribution passage 80 Injection pump (Distribution type fuel injection pump) 82 Cylinder 83 Distribution rotor 86 First fuel passage 87 Second fuel passage 88 Fuel inlet 89 Fuel discharge port 92, 93 Distribution passage

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takao Naganuma 1-1-1, Showa-cho, Kariya city, Aichi Prefecture Nihondenso Co., Ltd.

Claims (3)

[Claims] 1. A distribution type fuel injection pump that pressurizes and sucks and distributes fuel sucked into a fuel pressurizing chamber by a plunger that reciprocates according to the profile of a cam, and rotates in synchronization with an internal combustion engine. A distribution rotor that supports a plunger so as to be capable of reciprocating in a radial direction, wherein a fuel intake port is provided on an outer peripheral wall of the distribution rotor and an outer peripheral wall of the distribution rotor is axially farther from the fuel pressurizing chamber than the fuel intake port. A fuel discharge port, a first fuel passage communicating the fuel pressurizing chamber and the fuel suction port, and a second fuel passage communicating the fuel suction port and the fuel discharge port. A distribution rotor, a suction passage through which fuel can be supplied to the fuel pressurization chamber through the fuel suction port, and a distribution passage through which the fuel discharge port can communicate with each other. And the second fuel passage extends from the fuel suction port toward the fuel discharge port in a direction away from a virtual plane including the rotation shafts of the fuel suction port and the distribution rotor. Distributed fuel injection pump. 2. A distribution type fuel injection pump which pressurizes and sucks and distributes fuel sucked into a fuel pressurizing chamber by a plunger that reciprocates according to the profile of a cam, and rotates in synchronization with an internal combustion engine. A distribution rotor that supports a plunger so as to be capable of reciprocating in a radial direction, wherein a fuel intake port is provided on an outer peripheral wall of the distribution rotor and an outer peripheral wall of the distribution rotor is axially farther from the fuel pressurizing chamber than the fuel intake port. A fuel discharge port, a first fuel passage communicating the fuel pressurizing chamber and the fuel suction port, and a second fuel passage communicating the fuel suction port and the fuel discharge port. A distribution rotor, a suction passage that can communicate with the fuel suction port and can supply fuel to the fuel pressurizing chamber, and a distribution passage that communicates with the fuel discharge port are provided to rotatably support the distribution rotor. And a cylinder, the extension line of the distribution passage distributor type fuel injection pump, characterized in that deviates from the axis of rotation of the dispensing rotor. 3. The second fuel passage extends from the fuel suction port toward the fuel discharge port in a direction away from a virtual plane including the rotation shafts of the fuel suction port and the distribution rotor. The distributed fuel injection pump according to claim 2.