JP2010007622A - Fluid pressure-feed device - Google Patents

Abstract

A fluid pumping device capable of suppressing adverse effects caused by overlapping pumping periods of a plurality of pumping units is provided.
The apparatus includes a supply pump. The supply pump has a cam that is driven by the output shaft of the internal combustion engine, and includes three pressure-feeding portions 45A each composed of a plunger that is driven by the cam to reciprocate and a cylinder that is attached with the plunger inserted. 45B and 45C. The amount of fluid pumped with one reciprocation of the plunger is set to a different amount in each pumping section 45A, 45B, 45C.
[Selection] Figure 6

Description

  The present invention relates to a fluid pressure feeding device having a fluid pump driven by an output shaft of an internal combustion engine.

  As this type of fluid pressure feeding device, for example, a device for supplying fuel to an internal combustion engine is known (see, for example, Patent Document 1). This device is provided with a fuel pump for pumping fuel, and this fuel pump includes an input shaft connected to the output shaft of the internal combustion engine, and a drive unit (specifically, a drive unit attached to the input shaft). , Cam). Further, the fuel pump includes a plurality of plungers that are individually driven by the driving unit to reciprocate, and the same number of cylinders as the plungers that are individually attached in a state where the plungers are inserted.

Then, when the input shaft of the fuel pump is driven to rotate in accordance with the operation of the internal combustion engine, the drive unit is driven by the input shaft to reciprocate the plunger, and the fuel is sucked into each cylinder accordingly. At the same time, the fuel is pumped.
Japanese Patent Laid-Open No. 2006-200393

  Here, in the case where the fuel pump is provided with a plurality of pumping parts composed of plungers and cylinders as in the above-described device, the fuel is simply pumped from each pumping part in order to increase the pumping amount of the fuel. If the period (pumping period) is increased, the pumping periods of the respective pumping units will overlap.

  When such a pumping period overlaps, the torque required for driving the fuel pump may temporarily increase due to this, which causes various inconveniences such as an increase in fuel consumption of the internal combustion engine. This is not preferable because it contributes to the inconvenience.

  In addition, not only the apparatus provided with the fuel pump for supplying fuel to the internal combustion engine described above but also the apparatus provided with a fluid pump for pumping fluid other than fuel such as oil, such a situation is generally common. It has become a thing.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a fluid pumping device that can suppress adverse effects caused by overlapping pumping periods of a plurality of pumping units.

Hereinafter, means for achieving the above-described object and its operation and effects will be described.
The invention according to claim 1 has a drive unit connected to the output shaft of the internal combustion engine and driven by the output shaft, and a plunger driven by the drive unit to reciprocate and a state in which the plunger is inserted. In a fluid pumping device including a fluid pump having a plurality of pumping units each including an attached cylinder, the amount of fluid pumped with one reciprocating movement of the plunger is set to a different amount in the plurality of pumping units. It is the gist of what has been done.

  According to the above configuration, the pumping amount of each pumping unit is set individually with a much higher degree of freedom compared to a device in which the amount of fluid pumped from a plurality of pumping units (pumping amount) is set to an equal amount. Thus, the operation characteristics of the fluid pump can be set with a high degree of freedom. For this reason, it is possible to accurately suppress adverse effects due to overlapping of periods (pumping periods) in which fluid is pumped from the respective pumping parts through setting of the operation characteristics of the fluid pump.

  According to a second aspect of the present invention, in the fluid pressure feeding device according to the first aspect, fluids are respectively supplied from a common base passage to the plurality of pressure feeding portions, and the base passage and the plurality of pressure feeding portions. The gist of the present invention is that the passage cross-sectional area of the portion of the communication passage that communicates with each cylinder separately is set to a different value.

  According to the above configuration, by setting the passage cross-sectional area of the communication passage that communicates the base passage and the cylinder of each pressure feeding portion to a different value, the amount of fluid pumped by one reciprocation of the plunger is reduced. Different amounts can be set in a plurality of pumping units.

  According to a third aspect of the present invention, in the fluid pumping device according to the first or second aspect, a relative ratio between the plurality of pumping units with respect to the amount of the pumped fluid according to an operating state of the internal combustion engine. The gist of the present invention is that a changing means for changing is provided.

  According to the said structure, the freedom degree about the setting of the pumping amount of each pumping part can be made higher, and the operating characteristic of a fluid pump can be set with a higher freedom degree here. And it becomes possible to suppress more precisely the bad influence by duplication of the pumping period about each pumping part by this.

  According to a fourth aspect of the present invention, in the fluid pumping device according to the third aspect, when the change unit is an operating state in which the operating state of the internal combustion engine is a small required amount for the amount of fluid to be pumped. Furthermore, the gist is that the pumping of the fluid from at least one of the plurality of pumping units is stopped and the pumping of the fluid is performed by the remaining pumping units.

  Normally, when the pressure of the fluid increases with the movement of the plunger of the pumping part, the pressure between the part that has become high in this way and the part that supplies the fluid into the cylinder of the pumping part (low pressure part) Due to the difference, it is inevitable that a small amount of fluid leaks to the same low pressure portion side, and the operation efficiency of the fluid pump is reduced accordingly.

  In this regard, according to the above-described configuration, the fluid pressure of the portion corresponding to the pumping unit does not increase during the operation period of the fluid pump corresponding to the pumping unit in which the pumping of the fluid among the plurality of pumping units is stopped. In addition, fluid leakage to the low pressure portion side can be suppressed, and the operating efficiency of the fluid pump can be increased accordingly. In addition, a sufficient pumping amount can be ensured by the pumping unit that pumps the fluid among the plurality of pumping units.

The gist of the invention described in claim 5 is the fluid pumping device according to any one of claims 1 to 4, wherein the fluid pump includes three or more pumping sections.
A fluid pump having three or more pumping units is likely to overlap in the pumping period for each pumping unit due to its structure. In this regard, according to the above configuration, in the apparatus including such a fluid pump, it is possible to accurately suppress adverse effects due to the overlap of the pumping periods of the pumping units.

  In addition, the structure as described in any one of Claims 1-5 is applicable to the apparatus provided with the fuel pump for supplying a fuel to an internal combustion engine as a fluid pump like Claim 6. it can.

Hereinafter, an embodiment embodying a fluid pressure feeding device according to the present invention will be described.
FIG. 1 shows a schematic configuration of a fuel supply system of an internal combustion engine to which a fluid pumping device according to the present embodiment is applied.

  As shown in FIG. 1, the fuel supply system 11 of the internal combustion engine 10 includes a fuel tank 12, and fuel as a fluid is stored in the fuel tank 12. The fuel tank 12 is connected to a delivery pipe 13 via a supply pump 20. The fuel in the fuel tank 12 is pumped to the delivery pipe 13 by the supply pump 20. A fuel injection valve 14 is attached to the delivery pipe 13, and fuel inside the delivery pipe 13 is injected through the valve opening drive of the fuel injection valve 14 and supplied to the internal combustion engine 10.

  The supply pump 20 is provided with a feed pump 21, a control valve 30, and a high-pressure pump 40 in order from the fuel tank 12 side. The feed pump 21 pumps up the fuel in the fuel tank 12 and sends it to the high-pressure pump 40. The adjustment valve 30 adjusts the amount of fuel sucked into the high-pressure pump 40 by adjusting the amount of fuel sent from the feed pump 21 to the high-pressure pump 40. Through the operation control of the control valve 30, the amount of fuel pumped from the supply pump 20 (specifically, the high pressure pump 40) is adjusted. The high-pressure pump 40 pumps the fuel pressure to the delivery pipe 13 while increasing the fuel pressure.

  The input shaft 22 of the supply pump 20 is connected to the output shaft 15 of the internal combustion engine 10, and the feed pump 21 and the high-pressure pump 40 are driven by the input shaft 22. That is, the feed pump 21 and the high-pressure pump 40 are of an engine drive type that is driven by the output shaft 15 of the internal combustion engine 10.

  The apparatus of the present embodiment includes various sensors for detecting the operating state of the internal combustion engine 10, such as a speed sensor 16 for detecting the rotational speed of the output shaft 15 (engine rotational speed NE) of the internal combustion engine 10, for example. Is provided. In addition, the apparatus according to the present embodiment includes an electronic control unit 17 mainly composed of a microcomputer, for example. The electronic control unit 17 captures output signals of various sensors and performs various calculations based on the output signals. Based on the calculation results, the electronic control unit 17 performs various operations such as operation control of the control valve 30 and operation control of the fuel injection valve 14. Execute control.

Hereinafter, the structure of the high-pressure pump 40 will be described in detail.
2A to 2C schematically show the internal structure of the high-pressure pump 40. FIG.
As shown in FIG. 2A, an eccentric portion 41 is provided on the input shaft 22 of the supply pump 20. The eccentric portion 41 is formed in a columnar shape, and is provided on the input shaft 22 so that the columnar shaft center and the rotation center C of the input shaft 22 do not coincide with each other and are parallel to each other. A cam 42 is attached to the eccentric portion 41 so as to be rotatable relative to the eccentric portion 41. Specifically, when the cam 42 is rotated relative to the eccentric portion 41, the cam 42 is attached to the eccentric portion 41 so that the rotation center of the cam 42 and the axis of the eccentric portion 41 coincide with each other.

  The high-pressure pump 40 is provided with three pressure-feeding portions 45 each composed of a cylinder 43 and a plunger 44 that is inserted in the cylinder 43 so as to be reciprocally movable. On the outer peripheral surface of the cam 42, portions (pressing portions 46) formed in a planar shape are formed at intervals of 120 ° around the rotation center. One end of each plunger 44 is in contact with each of the pressing portions 46. A spring 47 is provided between the cylinder 43 and the plunger 44, and the plunger 44 is pressed against the pressing portion 46 of the cam 42 by the urging force of the spring 47.

  The inside of the cylinder 43 is connected to the feed pump 21 via the first check valve 48. The first check valve 48 allows fuel to flow from the feed pump 21 side to the cylinder 43 side, while restricting fuel flow from the cylinder 43 side to the feed pump 21 side. Further, the inside of the cylinder 43 is connected to the delivery pipe 13 via the second check valve 49. The second check valve 49 allows fuel to flow out from the cylinder 43 side to the delivery pipe 13 side, while restricting fuel inflow from the delivery pipe 13 side to the cylinder 43 side.

  When the operation of the internal combustion engine 10 is started and the input shaft 22 of the supply pump 20 is rotationally driven, the eccentric portion 41 and the cam 42 rotate, and the shaft center rotates around the rotation center C of the input shaft 22. Rotate as you do. The plunger 42 is periodically pressed against the urging force of the spring 47 by the cam 42 so that the plunger 44 reciprocates inside the cylinder 43 so that the fuel is pumped from each pumping section 45. become. In the high-pressure pump 40 of the present embodiment, fuel is pumped from the three pumping sections 45 toward the delivery pipes 13 at timings whose rotational phases are shifted from each other by 120 degrees.

Each pumping unit 45 pumps fuel in the following manner.
That is, first, as shown in FIG. 2A, the fuel is not pumped when the volume of the cylinder 43 (specifically, the cylinder 43 shown in the upper part of the figure) is at its minimum.

  Then, as shown in FIG. 2B, when the input shaft 22 of the supply pump 20 thereafter rotates and the plunger 44 moves in the direction of enlarging the volume of the cylinder 43, the fuel in the cylinder 43 is accompanied accordingly. Pressure is lowered. As a result, the first check valve 48 is opened, and fuel is sucked from the feed pump 21 side to the cylinder 43 side. At this time, the second check valve 49 is closed, and the inflow of fuel from the delivery pipe 13 side to the cylinder 43 side is restricted.

  Thereafter, as shown in FIG. 2 (c), when the input shaft 22 of the supply pump 20 further rotates and the plunger 44 moves in a direction to reduce the volume of the cylinder 43, the inside of the cylinder 43 is accordingly moved. Fuel pressure increases. As a result, the second check valve 49 is opened and fuel is discharged from the cylinder 43 side to the delivery pipe 13 side. At this time, the first check valve 48 is closed to restrict the outflow of fuel from the cylinder 43 side to the feed pump 21 side. 2B and 2C show two pumping parts other than the pumping part 45 that explains the fuel pumping mode.

  Here, the supply pump 20 of the present embodiment includes three pumping units 45 (see FIG. 2B), and the period during which fuel is pumped from the pumping units 45 (pumping period) overlaps. Is inevitable. Such overlapping of the pumping periods causes a variety of inconveniences such as temporarily increasing the torque (drive torque) required for driving the supply pump 20 to increase the fuel consumption of the internal combustion engine 10. Therefore, it is not preferable.

  In view of this point, in the present embodiment, the amount of fuel pumped by one reciprocating movement of the plunger 44 (pumping amount) is set to a different amount in the three pumping portions 45. Thereby, compared with the apparatus of the comparative example in which the pumping amount of the three pumping units 45 is set to an equal amount, the pumping amount of each pumping unit 45 can be set individually with a remarkably high degree of freedom. Become. Therefore, it becomes possible to set the operating characteristics of the supply pump 20 with a high degree of freedom, and the period during which fuel is pumped from each pumping unit 45 through the setting of the operating characteristics of the supply pump 20 (pumping period) overlaps. It is possible to accurately suppress the adverse effects caused by.

FIG. 3 shows a hydraulic circuit of the fuel supply system 11 of the internal combustion engine 10, and FIG. 4 shows a cross-sectional structure of the control valve 30.
As shown in FIG. 3, the fuel is supplied to the path from the fuel tank 12 to the control valve 30 in the fuel supply system 11 through the base passage 18 common to the pressure feeding units 45.

  As shown in FIGS. 3 and 4, the control valve 30 includes a single valve body 31, and includes two valve portions 32 and 33 whose opening degrees change as the valve body 31 moves. One valve portion 32 of the control valve 30 is connected to the communication passage 23Aa, and the communication passage 23Aa is connected to one pressure feeding portion 45A. The other valve portion 33 of the control valve 30 is connected to the communication passages 23Ab, 23B, and 23C. The communication passage 23Ab communicates with the pressure feeding portion 45A, the communication passage 23B communicates with the pressure feeding portion 45B, and the communication passage 23C. Is communicated with the pressure feeding section 45C.

  In this embodiment, the passage areas of the four communication passages 23Aa, 23Ab, 23B, and 23C that communicate each pressure feeding portion 45 and the control valve 30 separately are minimized. Is set to a value. Specifically, each of the communication passages 23Aa, 23Ab, 23B, and 23C has a substantially constant passage cross-sectional area, and the passage cross-sectional areas of the communication passages 23Aa, 23Ab, 23B, and 23C are set to different values. Specifically, the passage sectional area of each of the communication passages 23Aa, 23Ab, 23B, and 23C is expressed by the following relational expression (“23Aa passage sectional area” + “23Ab passage sectional area”> “23B passage sectional area” ≈ “23C passage cross-sectional area”) is set.

  In this manner, by setting the passage cross-sectional areas of the communication passages 23Aa, 23Ab, 23B, and 23C communicating with the base passage 18 and each of the pressure feeding portions 45 (specifically, the cylinder 43 (see FIG. 2)) to different values. The amount of fuel that passes through the communication passages 23Aa, 23Ab, 23B, and 23C per unit time is different, and the amount of fuel that flows into each pumping unit 45 is different. As a result, the amount of fuel pumped by one reciprocating movement of the plunger 44 becomes different in each pumping section 45A, 45B, 45C.

  Further, in the present embodiment, through the operation control of the control valve 30, the amount of fuel that is pumped with one reciprocating movement of the plunger 44 (the pumping amount) between the pumping units 45 </ b> A, 45 </ b> B, 45 </ b> C. The relative ratio is changed. Thereby, the freedom degree about the setting of the pumping amount of each pumping part 45A, 45B, 45C can be made higher, and the operating characteristic of the supply pump 20 can be set with a higher degree of freedom. And it becomes possible to suppress more precisely the bad influence by duplication of the pumping period about each pumping part 45A, 45B, 45C by this.

FIGS. 5A and 5B show an example of the operation mode of the control valve 30. FIG.
As shown in FIG. 5 (a), when the required amount for the pumping amount (specifically, the integrated value of the pumping amount of each pumping unit 45) is small, the valve unit 32 is opened, while the valve unit 33 is Closed state. At this time, since the fuel does not flow into each of the communication passages 23Ab, 23B, 23C (see FIG. 3), the pumping of the fuel from the pressure feeding portions 45B, 45C is stopped and the fuel flows into the communication passage 23Aa. The fuel is pumped by the portion 45A. The communication passage 23Ab (see FIG. 3) is a passage for supplying fuel supplementarily to the pressure feeding portion 45A when the valve portion 33 of the control valve 30 is opened. When 33 is in a closed state, the fuel is hardly supplied to the pressure feeding portions 45B and 45C through the communication passage 23Ab.

  On the other hand, as shown in FIG. 5B, when the required amount for the pumping amount is relatively large, the two valve portions 32 and 33 are both opened. At this time, the fuel is supplied to all the communication passages 23Aa, 23Ab, 23B, and 23C, and the fuel is pumped from all the pressure feeding sections 45A, 45B, and 45C.

  In the present embodiment, the control command value output from the electronic control unit 17 to the control valve 30 is the operating state of the internal combustion engine 10, specifically, the engine speed NE and the fuel injection amount (injection from the fuel injection valve 14). The amount of fuel to be controlled). As a result, the operation of the control valve 30 (specifically, the movement position of the valve body 31) is controlled in a manner corresponding to the required amount of the pumping amount.

  FIG. 6 shows the relationship between the control command value and the pumping amount of each pumping section 45 under the condition that the engine speed NE is constant. In FIG. 6, the line L1 indicates the above-described relationship regarding the pumping amount by the pumping unit 45A, the line L2 indicates the above-described relationship regarding the pumping amount by the pumping unit 45B (or 45C), and the line L3 indicates all the lines. The said relationship about the integrated value of the pumping amount by the pumping part 45 is shown.

  As shown in FIG. 6, when the operating state of the internal combustion engine 10 is an operating state in which the required amount for the pumping amount is small, fuel is pumped only by the pumping unit 45A (region (A)). At this time, the operation of the adjustment valve 30 is controlled so that the pumping amount of the pumping unit 45A increases as the required amount of the pumping amount increases.

  Here, in the high-pressure pump 40, when the pressure of the fuel in the portion communicated with the cylinder 43 increases as the plunger 44 of the pressure-feeding portion 45 moves, this portion and the relatively low-pressure portion (the first in the fuel supply system 11). 1) The pressure difference from the check valve 48 to the feed pump 21 side) increases. Due to this pressure difference, for example, it is unavoidable that a small amount of fuel leaks from a portion communicating with the cylinder 43 through a gap between the cylinder 43 and the plunger 44 to a relatively low pressure portion. Only the operating efficiency of the supply pump 20 is reduced.

  FIG. 7 shows an example of the relationship between the rotation phase of the supply pump 20 and the drive torque. In FIG. 7, the solid line indicates the above relationship when the fuel is pumped only by the pumping unit 45A, and the alternate long and short dash line indicates the pumping when the pumping amount of each pumping unit 45 is set to an equal amount. The above relationship for the portion 45B is shown, and the two-dot chain line shows the above relationship for the pumping portion 45C when similarly assumed.

  As is clear from FIG. 7, when fuel is pumped only by the pumping unit 45A, the fuel does not flow into the pumping units 45B and 45C. During the period indicated by T), the pressure of the fuel in the portion where the cylinders 43 of the pumping portions 45B and 45C are communicated does not increase. Therefore, in such a period, it is possible to suppress the fuel from leaking from the portion communicating with the cylinder 43 to the relatively low pressure portion, and in the comparative example in which the pumping amounts of the three pumping portions 45 are set to equal amounts. Compared with the apparatus, the operation efficiency of the supply pump 20 can be increased accordingly. In addition, in this case, a sufficient pumping amount can be secured through the fuel pumping by the pumping unit 45A.

  Further, as shown in FIG. 6, when the required amount for the above-mentioned pumping amount increases, in addition to the fuel pumping by the pumping unit 45A, the fuel pumping by the pumping units 45B and 45C is performed (region (b) )). At this time, the operation of the control valve 30 is controlled so that the pumping amount of each pumping unit 45A, 45B, 45C increases as the required amount for the pumping amount increases.

FIG. 8 shows an example of the relationship between the rotational phase of the supply pump 20 and the driving torque necessary for driving each pressure feeding unit 45 when the fuel is pumped by all the pressure feeding units 45.
In the apparatus of the present embodiment, as shown in FIG. 8, the driving torque of the supply pump 20 is large when the fuel is pumped by the pumping unit 45A, and the driving torque of the supply pump 20 is compared when the fuel is pumped by the pumping units 45B and 45C. Small. Therefore, although the drive torque of the supply pump 20 when the pumping periods of the pumping units 45A and 45B overlap is increased, the pumping periods of the pumping units 45B and 45C overlap or when the pumping units 45A and 45C are pumped. When the periods overlap, the drive torque of the supply pump 20 can be kept very small.

  In this way, by adopting a configuration in which the pumping amount of each pumping unit 45 is set to a different amount, the pumping amount of each pumping unit 45 is set to be equal to that of the comparative example in which the pumping amount of each pumping unit 45 is set to an equal amount. The degree of freedom in setting is greatly increased. As a result, the room for adjusting the drive torque of the supply pump 20 during the period in which the pumping periods of the pumping units 45 overlap is significantly increased. Therefore, by setting the operating characteristics of the supply pump 20 (specifically, the cross-sectional areas of the communication passages 23Aa, 23Ab, 23B, and 23C and the characteristics of the control valve 30) based on the results of experiments and simulations. Although the overlap of the pumping periods of the pumping units 45 is unavoidable, adverse effects due to the overlap can be accurately suppressed.

As described above, according to the present embodiment, the effects described below can be obtained.
(1) The pumping amount of each pumping unit 45 is set to a different amount. Thereby, compared with the apparatus of the comparative example in which the pumping amount of each pumping unit 45 is set to an equal amount, the pumping amount of each pumping unit 45 can be set individually with a significantly higher degree of freedom. The operating characteristics of the supply pump 20 can be set with a high degree of freedom. For this reason, it is possible to accurately suppress adverse effects due to the overlap of the pumping periods of the pumping units 45 through the setting of the operation characteristics of the supply pump 20.

  (2) The fluid is supplied from the common base passage 18 to the pressure feeding portions 45, and the communication passages 23Aa, 23Ab, 23B, and 23C communicate the base passage 18 and the cylinders 43 of the pressure feeding portions 45 separately. By setting the cross-sectional areas of the passages to different values, the pumping amount of each pumping portion 45 can be set to a different amount.

  (3) Since the relative ratio between the pumping units 45 with respect to the pumping amount is changed according to the operating state of the internal combustion engine 10, the degree of freedom for setting the pumping amount of each pumping unit 45 is increased. Therefore, the operating characteristic of the supply pump 20 can be set with a higher degree of freedom. As a result, it is possible to more accurately suppress the adverse effects caused by the overlap of the pumping periods for the pumping units 45.

  (4) When the operation state of the internal combustion engine 10 is an operation state in which the necessary amount for the pumping amount is small, the fuel pumping from the pumping units 45B and 45C is stopped and the fluid is pumped by the pumping unit 45A. did. Therefore, it is possible to prevent fuel from leaking from a portion where the cylinder 43 is communicated to a relatively low pressure portion during a period in which each of the pressure feeding portions 45B and 45C is operated, and the pressure feeding amounts of the three pressure feeding portions 45 are equal. Compared with the apparatus of the comparative example set to the amount, the operation efficiency of the supply pump 20 can be increased correspondingly. In addition, in this case, a sufficient pumping amount can be secured through the fuel pumping by the pumping unit 45A.

The embodiment described above may be modified as follows.
The relationship between the control command value and the pumping amount of each pumping unit 45 is not limited to the relationship shown in FIG. 6 and can be arbitrarily changed. In short, based on the results of experiments and simulations, the above relationship should be set so that the adverse effects of overlapping pumping periods of each pumping unit 45 can be accurately suppressed while securing the required amount of pumping. That's fine.

  As the operating state of the supply pump 20, an operating state in which fuel pumping from one of the pumping units 45 is stopped and fuel pumping is performed by the remaining two may be adopted.

  -You may set the cross-sectional area of each communicating path 23Aa, 23Ab, 23B, 23C to the same value. In this case, an adjustment valve 30 that can appropriately adjust the amount of fuel passing through each of the communication passages 23Aa, 23Ab, 23B, and 23C (passing fuel amount) is adopted. The amount of fuel passing through may be adjusted through operation control. It is also possible to newly provide a control valve for metering the amount of passing fuel and metering the amount of passing fuel through the operation control of the control valve.

The fuel may be pumped from all the pumping units 45 even when the operating state of the internal combustion engine 10 is an operating state in which the necessary amount for the pumping amount is small.
-The control valve 30 may be omitted.

  The present invention is applicable not only to a device having a supply pump having three pumping units, but also to a device having a supply pump having two pumping units and a device having a supply pump having four or more pumping units. can do.

The present invention is not limited to a device having a supply pump that pumps fuel, but can be applied to a device having a fluid pump that pumps fluid other than fuel, such as oil.
The present invention is connected to an output shaft of an internal combustion engine, such as a device having a fluid pump driven by a swash plate, as well as a device having a fluid pump driven by a cam, and driven by the output shaft. Any device provided with a fluid pump driven by a drive unit can be applied.

1 is a schematic diagram showing a schematic configuration of a fuel supply system of an internal combustion engine to which a fluid pumping device according to an embodiment embodying the present invention is applied. (A)-(c) The schematic which shows the internal structure of a supply pump roughly. 1 is a schematic diagram showing a hydraulic circuit configuration of a fuel supply system of an internal combustion engine. Sectional drawing which shows the cross-section of a control valve. (A) And (b) The expanded sectional view which shows an example of the operation | movement aspect of a control valve. The graph which shows the relationship between a control command value and the pumping amount of each pumping part. The time chart which shows an example of the relationship between the rotation phase of a supply pump, and a drive torque. The time chart which shows the other example of the relationship between the rotation phase of a supply pump, and a drive torque.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 11 ... Fuel supply system, 12 ... Fuel tank, 13 ... Delivery pipe, 14 ... Fuel injection valve, 15 ... Output shaft, 16 ... Speed sensor, 17 ... Electronic control unit, 18 ... Base passage, 20 ... Supply pump, 21 ... feed pump (fluid pump), 22 ... input shaft, 23Aa, 23Ab, 23B, 23C ... communication path, 30 ... control valve (changing means), 31 ... valve element, 32,33 ... valve part, 40 ... high pressure pump, 41 ... eccentric part, 42 ... cam (drive part), 43 ... cylinder, 44 ... plunger, 45, 45A, 45B, 45C ... pressure feeding part, 46 ... pressing part, 47 ... spring, 48 ... first reverse Stop valve, 49 ... second check valve.

Claims (6)

A pumping unit having a drive unit connected to an output shaft of an internal combustion engine and driven by the output shaft, and comprising a plunger driven by the drive unit to reciprocate and a cylinder attached with the plunger inserted. In a fluid pumping device provided with a fluid pump having a plurality of
The fluid pumping device, wherein the amount of fluid pumped with one reciprocation of the plunger is set to a different amount in the plurality of pumping units. The fluid pumping device according to claim 1,
A fluid is supplied to each of the plurality of pumping parts from a common base passage, and the base passage and the cylinders of the plurality of pumping parts communicate with each other, and the cross-sectional area of the passage is minimized. The fluid pressure feeding device is characterized in that the cross-sectional area of the same passage is set to a different value. In the fluid pumping device according to claim 1 or 2,
A fluid pumping device comprising: a changing unit that changes a relative ratio between the plurality of pumping units with respect to the amount of fluid pumped according to an operating state of the internal combustion engine. In the fluid pumping device according to claim 3,
The changing means stops the pumping of fluid from at least one of the plurality of pumping units when the operating state of the internal combustion engine is an operating state in which a required amount of the fluid to be pumped is small. In addition, the fluid pumping device is characterized in that the fluid is pumped by the remaining pumping unit. In the fluid pumping device according to any one of claims 1 to 4,
The fluid pump is provided with three or more pumping units. In the fluid pumping device according to any one of claims 1 to 5,
The fluid pumping device, wherein the fluid pump is a fuel pump for supplying fuel to the internal combustion engine.

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