JP4605092B2 - Fuel supply pump - Google Patents

Description

  The present invention relates to a fuel supply pump configured to pressurize and increase the pressure of fuel sucked into a cylinder through an electromagnetic valve and supply the fuel to a fuel injection valve side of an internal combustion engine.

[Conventional technology]
2. Description of the Related Art Conventionally, a fuel supply pump (hereinafter referred to as a supply pump) configured to pressurize and increase the pressure of fuel sucked into a cylinder through a solenoid valve and supply it to the fuel injection valve side (injector side) of the internal combustion engine. Is known (see, for example, Patent Document 1). As shown in FIGS. 10 and 11, the supply pump includes a lower end surface (electromagnetic valve contact surface) of the valve body 102 of the electromagnetic valve 101 that controls the discharge amount of fuel and a cylinder 104 of the cylinder head 103. Between the upper end surface (cylinder contact surface), a disc-shaped stopper 107 that restricts the valve lift amount of the solenoid valve 101 is disposed.

  Here, the solenoid valve 101 includes an electromagnet including a coil 111 and a stator core 112, an armature 113 attracted to the magnetic pole surface side of the electromagnet by the electromagnetic force of the electromagnet, and an axial direction in conjunction with the armature 113. And a spool valve 114 that reciprocates. The spool valve 114 is seated on and disengaged from the valve shaft portion slidably received in the sliding hole 115 of the valve body 102 and the valve seat of the valve body 102 to close the fuel passage 116. It has a valve head (valve) that opens.

  The cylinder head 103 is assembled to the pump housing. The cylinder 104 has a cylinder hole 117 formed therein, and from the upper end of the cylinder 104 in the drawing to one side in the axial direction of the cylinder 104 (upward in the drawing). The cylinder portion 105 is extended and has a larger inner diameter than the diameter of the cylinder hole 117. A plunger 106 is slidably accommodated in the cylinder hole 117. The solenoid valve 101 is fastened and fixed to the inner periphery of the cylindrical portion 105.

In the figure, reference numeral 121 denotes a plurality of communication passages that connect the valve chamber 122 that houses the valve head of the spool valve 114 and the fuel pressurizing chamber 119, and are provided through the stopper 107. Reference numeral 123 in the figure denotes a fuel passage that connects the fuel passage 116 and a fuel gallery (not shown).
Further, the stopper 107 is electromagnetically coupled by an axial fastening axial force (screw fastening axial force of the solenoid valve 101) generated when the solenoid valve 101 is fastened and coupled (screw fastening) to the cylindrical portion 105 of the cylinder head 103. The valve 101 is held and fixed between the solenoid valve 101 and the cylinder head 103 while being sandwiched between the solenoid valve contact surface of the valve body 102 of the valve 101 and the cylinder contact surface of the cylinder 104 of the cylinder head 103.

The supply pump applies the screw tightening axial force of the solenoid valve 101 to the solenoid valve contact surface of the valve body 102 of the solenoid valve 101 and the illustrated upper end surface (contact surface) of the stopper 107, thereby Since the contact surface of the solenoid valve and the contact surface of the stopper 107 are in surface contact and are liquid-tightly adhered, a high-pressure fuel seal function is provided between the contact surfaces.
Further, the supply pump is configured such that the screw tightening axial force of the solenoid valve 101 is applied to the illustrated lower end surface (contact surface) of the stopper 107 and the cylinder contact surface of the cylinder 104 of the cylinder head 103, thereby Since the cylinder contact surface of the cylinder head 103 is in surface contact with the cylinder head and is liquid-tightly adhered, a high-pressure fuel seal function is provided between both contact surfaces.

[Conventional technical problems]
However, in the conventional supply pump, as shown in FIG. 11, the annular convex portion (solenoid valve contact portion) 131 of the valve body 102 of the solenoid valve 101 is radially outward from the stopper corner portion 132 of the stopper 107. It is provided so as to protrude to the radial side. For this reason, when the electromagnetic valve 101 is tightened and coupled to the cylindrical portion 105 of the cylinder head 103, the initial fastening axial force F1 of the electromagnetic valve 101 is applied to the electromagnetic valve contact portion 131 and the stopper 107 as shown in FIG. The stopper corner portion 132 of the stopper 107 is deformed by being added between the stopper corner portion 132 and the solenoid valve contact portion 131 slips to the radially outer diameter side, and the solenoid valve contact portion 131 moves outward in the radial direction. Deforms to the radial side.

  Further, when the fuel pressure in the fuel pressurizing chamber 119 increases by the plunger 106 ascending and pressurizing the fuel sucked into the fuel pressurizing chamber 119 when the electromagnetic valve 101 is closed, the state shown in FIG. As shown, the electromagnetic valve 101 is lifted upward in the figure by the pressure acting force P, and the fastening axial force F2 of the electromagnetic valve 101 is canceled and decreased. For this reason, the solenoid valve contact portion 131 that has been deformed to the radially outer diameter side by the initial fastening axial force F1 of the solenoid valve 101 is now deformed to the radially inner diameter side, and the solenoid valve contact portion 131 is deformed. Returned. As a result, a slight relative slip occurs between the contact surface of the stopper corner portion 132 of the stopper 107 and the electromagnetic valve contact surface of the electromagnetic valve contact portion 131.

On the other hand, in the cylinder head 103, when the fuel pressure in the fuel pressurizing chamber 119 is low (at the time of fuel suction or during low pressure action), the annular stepped portion 134 that is in close contact with the stopper corner portion 133 of the stopper 107 has an inner diameter in the radial direction. In addition, when the fuel pressure in the fuel pressurizing chamber 119 is high (when fuel is fed or when high pressure is applied), the annular step portion 134 is deformed to the radially outer diameter side. As a result, a slight relative slip occurs between the contact surface of the stopper corner 133 of the stopper 107 and the cylinder contact surface of the annular stepped portion 134.
These are repeated between the contact surface of the stopper corner portion 132 of the stopper 107 and the electromagnetic valve contact surface of the solenoid valve contact portion 131 and the stopper corner portion 133 of the stopper 107 by repeating the suction stroke and the pressure feed stroke of the supply pump. Sliding is repeated between the contact surface and the cylinder contact surface of the annular step portion 134. For this reason, there has been a problem that so-called fretting wear occurs due to slight repeated relative slip with frictional force between the contact surfaces.

When fretting wear occurs, the generated wear powder is not easily discharged, greatly affecting the wear and friction behavior between the contact surfaces, and a large frictional force is generated. Therefore, at the fretting operation position, the screw tightening axial force is reduced, and fuel leakage from the seal portion may occur. Also, due to stress concentration due to contact stress when fretting wear occurs, or due to fatigue failure from the wear surface due to stress concentration due to the accumulated wear powder partially rising and becoming a strong one-contact state, etc. Leading to the possibility of fretting fatigue.
Japanese Patent Laid-Open No. 3-219178 (page 1-4, FIG. 1 to FIG. 7)

  The objective of this invention is providing the fuel supply pump which can suppress generation | occurrence | production of fretting wear by reducing the amount of relative slips between a solenoid valve and a stopper. It is another object of the present invention to provide a fuel supply pump that can suppress the occurrence of fretting wear by reducing the amount of relative slip between the stopper and the cylinder. It is another object of the present invention to provide a fuel supply pump capable of eliminating problems such as fuel leakage from a seal portion and fatigue failure from a worn surface by suppressing the occurrence of fretting wear.

  According to the first aspect of the present invention, the plurality of plate members that are superposed in surface contact with each other constitute a stopper that regulates the valve lift amount of the electromagnetic valve. Then, by fixing the plurality of plate members while being sandwiched between the cylinder of the pump body and the electromagnetic valve, the number of sliding portions in the stopper increases, so that the relative slip amount between the electromagnetic valve and the stopper is reduced. be able to. Moreover, since the relative slip amount between the stopper and the cylinder can be reduced, the occurrence of fretting wear can be suppressed. Therefore, fuel leakage from the seal portion between the solenoid valve and the stopper and the seal portion between the stopper and the cylinder can be prevented. In addition, problems such as fatigue failure from the wear surface of the solenoid valve and the stopper and the wear surface of the stopper and the cylinder can be solved.

  Here, a plurality of plate members may be laminated in surface contact with each other in the axial direction or the plate thickness direction of the cylinder or the electromagnetic valve. Further, the electromagnetic valve may be coupled to the pump body by tightening. In this case, a plurality of plate members may be sandwiched between the cylinder and the solenoid valve by the fastening axial force of the solenoid valve. A plurality of plate members may be stacked in surface contact with each other in the direction in which the fastening axial force of the solenoid valve acts.

The plurality of plate members constituting the stopper are constituted by at least two first and second plate members. Then, by fixing the at least two first and second plate members sandwiched between the cylinder of the pump body and the electromagnetic valve, the number of sliding portions in the stopper increases, so that the contact surface of the electromagnetic valve and the first It is possible to reduce the relative slip amount between the first contact surface of the plate member and the relative slip amount between the second contact surface of the second plate member and the contact surface of the cylinder. The occurrence of problems such as leakage and fatigue failure can be reduced.

Further, when the solenoid valve opens, that is, when the solenoid valve opens the fuel passage, the cylinder passes through the first through hole of the first plate member and the second through hole of the second plate member from the fuel passage. Fuel is supplied into the cylinder hole. When the solenoid valve is closed, the solenoid valve closes the fuel passage .

Further, each of the plurality of second through holes penetrating the second plate member may be communicated with each of the first through holes among the plurality of first through holes penetrating the first plate member. . In this case, even if any of the plurality of first and second through holes is clogged with foreign matter or the like, the fuel can flow through the remaining first and second through holes.

According to invention of Claim 2 , the communication which makes a 1st through-hole and a 2nd through-hole communicate with the butt | matching part of the 1st through-hole of a 1st plate member, and the 2nd through-hole of a 2nd plate member. You may provide the recessed part in which the chamber was formed.
According to the invention described in claim 3 , the concave portion may be formed on the first contact surface of the first plate member or the second contact surface of the second plate member.
According to the fourth aspect of the present invention, all of the first through holes among the plurality of first through holes penetrating the first plate member and the plurality of second through holes penetrating the second plate member are included. You may form a recessed part (communication chamber) so that all the 2nd through-holes may be connected.

  Here, when providing a recessed part in the 1st close_contact | adherence surface of a 1st plate member, it dents toward the solenoid valve side from the 1st close_contact | adherence surface of a 1st plate member. The inner diameter of the recess may be larger than the diameter of the first through hole, and the first through hole may be opened at the bottom wall surface of the recess. Moreover, when providing a recessed part in the 2nd contact surface of a 2nd plate member, it is made to dent toward the cylinder side from the 2nd contact surface of a 2nd plate member. Note that the inner diameter of the recess may be larger than the hole diameter of the second through hole, and the second through hole may be opened at the bottom wall surface of the recess.

According to the fifth aspect of the present invention, the first contact surface of the first plate member is provided with the concave portion for reducing the contact area with the contact surface of the electromagnetic valve, so that the contact surface of the electromagnetic valve It is possible to improve the seal surface pressure with the first contact surface of the one plate member. Therefore, fuel leakage from the seal portion between the contact surface of the electromagnetic valve and the first contact surface of the first plate member can be prevented. Further, by providing the second contact surface of the second plate member with a concave portion for reducing the contact area with the contact surface of the cylinder, the seal between the second contact surface of the second plate member and the contact surface of the cylinder is provided. The surface pressure can be improved. Therefore, fuel leakage from the seal portion between the second contact surface of the second plate member and the contact surface of the cylinder can be prevented.

  The best mode for carrying out the present invention realizes the purpose of reducing the relative slip amount between the solenoid valve and the stopper by configuring the stopper with a plurality of plate members which are superposed in surface contact with each other. did. Further, the object of reducing the amount of relative slip between the stopper and the cylinder is realized by configuring the stopper with a plurality of plate members that are superposed in surface contact with each other.

[Configuration of Example 1]
1 to 3 show a first embodiment of the present invention, and FIG. 1 shows a supply pump.

  The fuel injection device for an internal combustion engine of the present embodiment is mounted in an engine room of a vehicle such as an automobile, and is mainly a fuel injection system for an internal combustion engine (multi-cylinder diesel engine: hereinafter referred to as an engine) such as a diesel engine. It is a common rail type fuel injection system (accumulation type fuel injection device) known as.

  This common rail fuel injection system includes a supply pump (fuel injection pump, fuel supply pump) that incorporates a feed pump (low pressure fuel pump) that pumps low pressure fuel from a fuel tank on the low pressure side of the fuel system, and the fuel of the supply pump A common rail into which high-pressure fuel is introduced from the discharge port, and a plurality of injectors (fuel injection valves of an internal combustion engine) to which high-pressure fuel is distributed and supplied from each fuel outlet of the common rail, and the high-pressure fuel accumulated in the common rail It is configured to inject and supply the combustion chamber for each cylinder of the engine via each injector.

  Here, the amount of current supplied to the solenoid valve 1 of the supply pump and each of the solenoid valves of the plurality of injectors is controlled by an engine control unit (hereinafter referred to as ECU) including a pump drive circuit and an injector drive circuit. It is configured as follows. The ECU includes a CPU that performs control processing and arithmetic processing, a storage device (memory such as ROM and RAM) that stores various programs and control data, an input circuit (input unit), an output circuit (output unit), and the like. A microcomputer having a known structure, a pump drive circuit connected to the solenoid valve 1 of the supply pump, and an injector drive circuit connected to each solenoid valve of the plurality of injectors are incorporated.

  Here, the supply pump of this embodiment is provided with a pump housing 11 for holding and fixing a pump element (a pump body of the supply pump, a high-pressure supply pump) constituted by the cylinder head 7 and the plunger 8. A pump drive shaft (camshaft) 12 that is rotationally driven by the crankshaft of the engine is rotatably supported on the pump housing 11. A feed pump that pumps low-pressure fuel from the fuel tank is connected upstream of the supply pump in the fuel flow direction.

  The pump housing 11 is formed of a metal material into a predetermined shape, and has a cam chamber filled with lubricating oil. A camshaft 12 that is rotationally driven by the crankshaft of the engine is inserted into the cam chamber of the pump housing 11. A cam 13 having three cam peaks is integrally assembled on the outer periphery of the camshaft 12. A drive pulley (not shown) is connected to the outer periphery of the distal end portion of the camshaft 12 so as to be driven and connected via a crank pulley and a belt of the crankshaft of the engine.

  A tappet 14 that slides in the vertical direction in the figure is disposed inside the pump housing 11. A roller 16 that is rotatable about a pin 15 as a support shaft is disposed at the lower portion of the tappet 14 in the figure. The tappet 14 is always urged downward in the figure by the urging force of the spring 17. Thereby, the tappet 14 is always in contact with the outer peripheral surface of the cam 13 via the roller 16. A cylinder head 7 is fitted in the upper end of the pump housing 11 in a liquid-tight manner. A fuel gallery chamber 19 into which low-pressure fuel is introduced from the feed pump is formed between the inner periphery of the pump housing 11 and the outer periphery of the cylinder head 7.

  The pump element of the supply pump includes a plunger 8 that reciprocates in the axial direction on the same axis as the spool valve 2 of the solenoid valve 1 and a cylinder head 7 that slidably supports the plunger 8. . The cylinder head 7 of this embodiment has a cylindrical cylinder 9 in which a cylinder hole for slidably receiving a plunger 8 is formed, and a cylinder in which a fitting hole for fitting and holding the electromagnetic valve 1 is formed. A cylindrical electromagnetic valve holding portion (hereinafter referred to as a cylindrical portion) 10 and the like are integrally formed. Here, 20 in FIG. 1 is an overflow valve that opens when the internal pressure of the fuel gallery chamber 19 of the supply pump rises above a predetermined value, and 21 in FIG. 1 is the interior of the pump housing 11 (cam chamber). , A sliding portion between the cylinder head 7 and the plunger 8, etc.), an inlet pipe 22 for introducing the lubricating oil, and an outlet pipe 22 for discharging the lubricating oil from the inside of the pump housing 11.

  The plunger 8 pressurizes the fuel sucked into the fuel pressurizing chamber 23 formed on the opening end side in the axial direction of the cylinder hole of the cylinder 9 to increase the pressure, and is accompanied by the cylinder 9 of the cylinder head 7. The pump element is configured. The plunger 8 is disposed so as to face the other end surface of the valve stopper in the plate thickness direction. Further, the lower end portion of the plunger 8 shown in the figure is fixed to an annular plate-shaped spring receiver 24 and is in contact with the upper end surface of the tappet 14 shown in the drawing. Here, the fuel pressurized as the internal volume of the fuel pressurizing chamber 23 expands and contracts with the reciprocating movement of the plunger 8 is supplied from the fuel pressurizing chamber 23 to the fuel discharge passage 25 and from the fuel discharge passage 25. It is configured to be pressure-fed and supplied to the common rail via a discharge valve 26 installed on the downstream side in the flow direction and a discharge port 29 of an outlet pipe 27 connected to a joint portion of the cylinder head 7. Details of the cylinder head 7 will be described later.

  Next, as shown in FIG. 1, the solenoid valve 1 of the supply pump is discharged from the fuel pressurizing chamber 23 by adjusting the amount of fuel sucked into the cylinder head 7 (fuel pressurizing chamber 23). A normally open type (normally open type) electromagnetic flow control valve that controls the amount of fuel discharged, a spool valve 2 that reciprocates in the axial direction, and an axial direction in which the spool valve 2 is slidably received It has a valve body 3 in which holes are formed. The electromagnetic valve 1 is integrally assembled with the cylindrical portion 10 of the cylinder head 7 of the supply pump.

  The solenoid valve 1 includes a valve seat 4 that regulates the valve lift amount of the solenoid valve 1 (particularly, the valve fully closed position of the spool valve 2), and the valve lift amount of the solenoid valve 1 (particularly the valve fully open position of the spool valve 2). And a valve stopper for regulating the pressure. The valve seat 4 is integrally formed with the lower end surface of the valve body 3 in the figure. The valve stopper is composed of a plurality of plate members (two first and second plate-like stoppers) 5, 6 and the like that are superposed in surface contact with each other in the direction in which the screw tightening axial force of the electromagnetic valve 1 acts. Has been. Here, the supply pump of the present embodiment is configured such that the two first and second plate-like stoppers 5 and 6 are sandwiched between the valve body 3 of the electromagnetic valve 1 and the cylinder 9 of the cylinder head 7. By tightening and fixing the valve 1 to the inner periphery of the cylindrical portion 10 of the cylinder head 7, the electromagnetic valve 1, the pump element, and the two first and second plate-like stoppers 5 and 6 are integrated.

  As shown in FIGS. 1 and 2, the solenoid valve 1 of the supply pump is a normally open type (normally open type) disposed on one side (the upper side in the drawing) of the cylinder 9 with respect to the cylinder hole. An electromagnetic control valve for energizing the spool valve 2 in the valve opening operation direction, an electromagnet having a coil for generating a magnetic force when energized, and an electromagnetic force of the electromagnet toward the magnetic pole surface side of the electromagnet An armature 31 to be attracted and a valve housing 32 that houses an electromagnet and the armature 31 are provided.

  The electromagnet of the electromagnetic valve 1 includes a coil that generates a magnetic flux when energized, a stator that is magnetized when an excitation current flows through the coil, and the like. A coil is a solenoid coil in which a conductive wire with an insulating coating is wound a plurality of times around the outer periphery of a coil bobbin and generates a magnetic attractive force (electromagnetic force) when an excitation current is supplied. The stator has a magnetic pole surface that is disposed to face the armature 31 with a predetermined gap therebetween. A press-fitting hole for press-fitting and fixing one end of the spool valve 2 in the axial direction is formed inside the armature 31.

  On the outer periphery of the valve housing 32 of the electromagnetic valve 1, a male screw portion 33 for screwing and fixing (screw fastening) the electromagnetic valve 1 to the inner periphery of the cylindrical portion 10 of the cylinder head 7 is formed. Further, on the outer periphery of the valve housing 32, a lower end surface of the valve body 3 of the solenoid valve 1 and an upper end surface of the cylinder 9 of the cylinder head 7 shown in FIG. An engaging portion 34 is provided that engages with a tool (for example, a torque wrench, a ratchet wrench, etc.) that is brought into close contact with the two first and second plate-like stoppers 5 and 6 by an axial force. The valve housing 32 is integrally assembled with a cylindrical connector 35 that holds a terminal for supplying power to the coil of the electromagnet. Note that an O-ring 36 for preventing leakage of fuel to the outside is mounted between the outer peripheral surface of the valve housing 32 and the inner peripheral surface of the cylindrical portion 10 of the cylinder head 7. Details of the spool valve 2 and the valve body 3 will be described later.

  Next, the main part of the supply pump of this embodiment, that is, the spool valve 2 of the solenoid valve 1, the valve body 3 of the solenoid valve 1, the cylinder head 7 of the pump element, and the two first and second plate-like stoppers 5, 6 Details will be described with reference to FIGS. Here, FIG. 2 is a view showing the main part of the supply pump, and FIG. 3 is an enlarged view of the main part of the supply pump, particularly the high-pressure seal part (high-pressure fuel seal, metal seal) of the supply pump.

  The solenoid valve 1 includes fuel supply passages (fuel passages) 41 to 43 and valve passage holes (valve holes, fuel passages) communicating with cylinder holes (particularly the fuel pressurizing chamber 23) formed inside the cylinder of the cylinder head 7. A spool valve 2 for opening and closing 45 is provided. Further, the spool valve 2 is configured to be driven to two positions of a valve fully open position (default position) and a valve fully closed position (full lift position) by electromagnetic force of an electromagnet coil built in the valve housing 32. Yes. The spool valve 2 is opened by the biasing force of the spring in a state where the energization to the coil of the electromagnet is stopped, and is closed against the biasing force of the spring when the coil of the electromagnet is energized. .

  The spool valve 2 is provided in a bowl shape so as to protrude from the outer periphery of the valve shaft portion 37 extending in the axial direction toward the outer diameter side in the radial direction from the outer periphery of the valve shaft portion 37 in the axial direction. A valve head 39 is provided. The valve shaft portion 37 has a sliding portion that is slidably accommodated in the axial hole of the valve body 3 and a small-diameter portion having an outer diameter smaller than that of the sliding portion. The end portion of the valve shaft portion 37 that protrudes from the upper end surface of the valve body 3 is press-fitted and fixed inside the armature 31 (the wall surface of the press-fit hole). The valve head portion 39 has an outer diameter larger than the outer diameter of the sliding portion and the small diameter portion of the valve shaft portion 37 and the hole diameter of the axial hole of the valve body 3. The valve head 39 forms a clearance through which fuel can pass between the valve head 39 and the valve seat 4 of the valve body 3 when the spool valve 2 is fully opened.

  The valve fully open position is a valve position at which the surface of the valve head 39 of the spool valve 2 abuts against the first plate-like stopper 5 to open (fully open) the valve channel hole 45 when the spool valve 2 is fully opened. That is. Further, the valve fully closed position means that when the spool valve 2 is fully closed, the back surface (valve face) of the valve head 39 of the spool valve 2 abuts the valve seat 4 of the valve body 3 so that the valve passage hole 45 is opened. It is the valve position that is closed (fully closed).

  And the solenoid valve 1 has the valve body 3 in which the axial direction hole which accommodates the spool valve 2 slidably was formed. The valve body 3 is coupled to the distal end side (lower end side in the drawing) of the valve housing 32 by caulking or the like. The valve body 3 has a cylindrical part (cylinder part) in which an axial hole is formed. Inside the valve body 3 is formed a fuel supply passage 43 through which fuel is introduced from the fuel gallery chamber 19 of the supply pump via the fuel supply passages 41 and 42. The fuel supply passage 42 is provided so as to surround the valve body 3 and is formed between the outer periphery of the valve body 3 and the inner periphery of the cylinder head 7. The fuel supply passage 43 is a fuel passage for introducing low-pressure fuel into a fuel pressurizing chamber provided on the opening end side of the cylinder 9 and is provided on the radially outer diameter side of the axial hole. Crosses the direction hole in a cross shape.

  An upper end portion of the axial hole of the valve body 3 is a valve sliding hole 44 in which a sliding portion of the valve shaft portion 37 of the spool valve 2 slides reciprocally. Further, the lower end portion of the valve body 3 in the axial direction is a diameter-expanding hole that gradually increases in diameter toward the lower side (cylinder side) and a circular hole that does not change its diameter. A valve channel hole 45 that is opened and closed by a valve head 39 of the spool valve 2 is provided at an intermediate portion between the valve sliding hole 44 and the diameter-expanded hole. Here, the space surrounded by the tapered hole wall surface of the enlarged diameter hole and the upper end surface of the first plate-like stopper 5 shown in the drawing is a valve that accommodates the valve head 39 of the spool valve 2 so as to be reciprocally movable in the axial direction. It is a storage chamber 46. The valve storage chamber 46 communicates with the fuel supply passage 43 through the valve flow path hole 45.

  The valve body 3 has a truncated cone-shaped valve seat (first valve seat portion) 4 on which the back surface (valve face) of the valve head 39 of the spool valve 2 can be seated. The valve seat 4 is an opening peripheral portion of the valve flow passage hole 45, that is, a tapered hole wall surface of the enlarged diameter hole, and is used as a restricting portion (valve seat surface) for restricting the operation range of the spool valve 2. Yes. Thus, when the back surface of the valve head portion 39 of the spool valve 2 is seated on the valve seat 4, the further operation of the spool valve 2 in the valve closing operation direction is restricted.

  Further, as shown in FIG. 3, the valve body 3 has a smaller contact area with the upper end surface of the first plate-like stopper 5 at the other end portion (lower end portion in the drawing) of the valve body 3 in the axial direction. An annular convex portion (electromagnetic valve contact portion) 51 is integrally formed for improving the sealing surface pressure between the illustrated lower end surface and the first contact surface of the first plate-like stopper 5. The illustrated lower end surface of the annular convex portion 51 is used as an annular contact surface (electromagnetic valve contact surface 52) that comes into surface contact with the illustrated upper end surface of the first plate-like stopper 5 in a liquid-tight manner. .

  The cylinder head 7 includes a cylindrical cylinder 9 having a cylinder hole 53 formed therein, and a cylindrical cylindrical portion 10 having a fitting hole 54 formed therein. A plunger 8 is accommodated in the cylinder hole 53 so as to be reciprocally movable. Thereby, the plunger 8 is slidably supported inside the cylinder 9. Here, a space surrounded by the hole wall surface on the opening end side of the cylinder hole 53 of the cylinder 9, the illustrated lower end surface of the second plate-like stopper 6, and the illustrated upper end surface of the plunger 8 is from the fuel gallery chamber 19 to the fuel supply passage. It is used as a fuel pressurizing chamber 23 that pressurizes the fuel sucked into the inside via the valve passage holes 41 to 43, the valve passage hole 45, and the valve housing chamber 46 and increases the pressure as the plunger 8 reciprocates. In addition, a female screw portion that is screwed with a male screw portion 33 formed on the outer periphery of the valve housing 32 of the electromagnetic valve 1 is formed on the inner periphery of the cylindrical portion 10 of the cylinder head 7.

  Here, a circular plate that accommodates two first and second plate-like stoppers 5 and 6 with a predetermined clearance at the opening peripheral edge of the fuel pressurizing chamber 23, that is, the opening peripheral edge of the cylinder hole 53. The housing hole 55 and a diameter-expanding hole that gradually increases in diameter toward the upper side (the valve housing side) are provided. An annular stepped portion 56 is provided between the opening end of the fuel pressurizing chamber 23, that is, between the opening end of the cylinder hole 53 and the plate accommodation hole 55. The illustrated upper end surface (annular step surface) of the stepped portion 56 serves as an annular contact surface (cylinder contact surface 57) that comes into surface contact with the illustrated lower end surface of the second plate-like stopper 6 and is liquid-tightly adhered. It's being used. It should be noted that the sheet contact area with the lower end surface of the second plate-like stopper 6 shown in the figure is reduced at the step portion 56 so that the seal surface pressure between the cylinder contact surface 57 of the cylinder 9 and the second contact surface of the second plate-like stopper 6 is reduced. You may provide the annular convex part for improving.

  The two first and second plate-like stoppers 5 and 6 are formed in an annular plate shape. These first and second plate-like stoppers 5 and 6 are provided with a predetermined fastening axial force (electromagnetic) generated when the valve housing 32 of the solenoid valve 1 is fastened to the inner periphery of the cylindrical portion 10 of the cylinder head 7. And is held and fixed in a state of being sandwiched between the solenoid valve contact surface 52 of the valve body 3 of the solenoid valve 1 and the cylinder contact surface 57 of the cylinder 9 of the cylinder head 7. ing.

  That is, the two first and second plate-like stoppers 5, 6 are in contact with the solenoid valve contact surface 52 of the valve body 3 of the solenoid valve 1 and the cylinder 9 of the cylinder 9 of the cylinder head 7 by the screw tightening axial force of the solenoid valve 1. It is sandwiched between the surface 57. Further, the two first and second plate-like stoppers 5 and 6 are provided in the direction in which the screw tightening axial force of the solenoid valve 1 acts, the axial direction of the valve body 3 of the solenoid valve 1, or the cylinder 9 of the cylinder head 7. Are laminated in liquid-tight surface contact with each other in the axial direction.

  The first plate-like stopper 5 has a second valve seat portion (valve stopper) on which the surface of the valve head 39 of the spool valve 2 can be seated on the upper end surface of the spool valve 2 facing the surface of the valve head 39 of the spool valve 2. (Contact portion, valve stopper) 59. The valve contact portion 59 is used as a restricting portion (stopper surface) that restricts the operating range of the spool valve 2. As a result, when the surface of the valve head 39 of the spool valve 2 comes into contact with the valve contact portion 59, further operation of the spool valve 2 in the valve opening operation direction is restricted.

  An annular first stopper corner 61 is integrally formed on the radially outer side of the first plate-like stopper 5 as shown in FIG. The first stopper corner 61 is a ring-shaped contact surface (first contact surface of the first plate-like stopper 5) that comes into liquid-tight contact with the solenoid valve contact surface 52 of the valve body 3 of the solenoid valve 1. 62). The first contact surface 62 is provided on the upper end surface of the first stopper corner 61 in the figure.

  Further, as shown in FIG. 3, an annular first stepped portion 63 that is one step lower than the first contact surface 62 is integrally formed at the radially outer end of the first plate-like stopper 5. Has been. The outer diameter surface of the first step portion 63 forms the maximum outer diameter portion of the first plate-like stopper 5. The first plate-like stopper 5 is superposed on one end surface in the plate thickness direction of the second plate-like stopper 6, and is in surface contact with one end surface in the plate thickness direction of the second plate-like stopper 6 to be liquid-tight. The first contact surface 64 is in close contact with the first contact surface 64.

Further, the first plate-like stopper 5 has both end faces in the plate thickness direction of the first plate-like stopper 5 (first contact surface 62) parallel to the axial direction of the valve body 3 of the electromagnetic valve 1 or the cylinder 9 of the cylinder head 7. The first contact surface 64) has two types of first through holes 65 and 66 that communicate with each other.
Only one first through hole 65 is arranged on the central axis in the stroke direction of the spool valve 2 and penetrates the central portion of the first plate-like stopper 5 in the plate thickness direction. The first through-hole 65 is provided in the center of the first plate-like stopper 5 and has a function of preventing the surface of the valve head 39 of the spool valve 2 from coming into close contact with the stopper surface.
A plurality of first through holes 66 are provided at a predetermined interval (for example, at equal intervals) on the same circumference of the first plate-like stopper 5 so as to partially surround the periphery of the first through hole 65. The end portion on the outer diameter side of the first plate-like stopper 5 is penetrated in the thickness direction. For example, eight first through holes 66 are provided at intervals of 45 °.

  As shown in FIG. 3, an annular second stopper corner 71 is integrally formed on the outer diameter side of the second plate-like stopper 6 in the radial direction. The second stopper corner 71 is an annular contact surface (second contact surface of the second plate-like stopper 6) 72 that comes into surface contact with the cylinder contact surface 57 of the cylinder 9 of the cylinder head 7 and comes into liquid-tight contact therewith. have. The second contact surface 72 is provided on the lower end surface of the second stopper corner 71 in the figure.

  Further, as shown in FIG. 3, an annular second stepped portion 73 that is one step higher than the second contact surface 72 is integrally formed at the radially outer end of the second plate-like stopper 6. Has been. The outer diameter surface of the second stepped portion 73 forms the maximum outer diameter portion of the second plate-like stopper 6. The second plate-like stopper 6 is superimposed on the other end surface (first adhesion surface 64) in the plate thickness direction of the first plate-like stopper 5, and faces the first adhesion surface 64 of the first plate-like stopper 5. It has the 2nd close_contact | adherence surface 74 which contacts and liquid-tightly adheres.

Further, the second plate-like stopper 6 has both end faces (second contact surfaces 72) in the thickness direction of the second plate-like stopper 6 parallel to the axial direction of the valve body 3 of the electromagnetic valve 1 or the cylinder 9 of the cylinder head 7. , The second contact surface 74) has two types of second through holes 75 and 76 communicating with each other.
Only one second through hole 75 is disposed on the central axis in the stroke direction of the spool valve 2 and penetrates the central portion of the second plate-like stopper 6 in the plate thickness direction. One second through hole 75 communicates with one first through hole 65.
A plurality of second through holes 76 are provided at predetermined intervals (for example, equal intervals) on the same circumference of the second plate-like stopper 6 so as to partially surround the periphery of the second through holes 75. The end portion on the outer diameter side of the second plate-like stopper 6 is penetrated in the thickness direction. For example, eight second through holes 76 are provided at intervals of 45 °.

The plurality of second through holes 76 communicate with each of the plurality of first through holes 66. Thus, when the surface of the valve head 39 of the spool valve 2 is in contact with the valve contact portion 59, the first and second through holes 65 and 75 are temporarily blocked by the surface of the valve head 39 of the spool valve 2. Even if this is done, since at least the plurality of first and second through holes 66 and 76 are open, it does not hinder the intake of fuel from the valve housing chamber 46 into the fuel pressurizing chamber 23.
The fuel supply passages 41 to 43, particularly the fuel supply passage 43 formed inside the valve body of the electromagnetic valve 1, includes a valve passage hole 45, a valve storage chamber 46, a plurality of first through holes 66, and a plurality of pieces. The second through hole 76 communicates with a cylinder hole (particularly the fuel pressurizing chamber 23) formed in the cylinder of the cylinder head 7.

[Operation of Example 1]
Next, the fuel sucked into the fuel pressurizing chamber 23 of the cylinder 9 through the solenoid valve 1 is pressurized and pressurized to be supplied to each injector mounted corresponding to each cylinder of the engine. The operation of the supply pump used as the fuel supply pump will be briefly described with reference to FIGS.

When the camshaft 12 of the supply pump is driven and rotated by the crankshaft of the engine, the tappet 14 and the roller 16 integrally reciprocate in the illustrated vertical direction along the outer peripheral surface (cam profile) of the cam 13. When the tappet 14 reciprocates in the vertical direction in the figure, the plunger 8 also reciprocates in the vertical direction in the figure in conjunction with the tappet 14.
At this time, the energization to the coil of the electromagnet is stopped (OFF), and the electromagnetic force of the electromagnet coil is demagnetized, so that the spool valve 2 is pressed against the valve of the first plate-like stopper 5 by the biasing force of the spring. It is pressed against the contact portion 59. That is, since the spool valve 2 is biased to the fully open position, the valve passage hole 45 of the solenoid valve 1 is opened (fully opened) by the spool valve 2.

  Further, when the plunger 8 descends in the cylinder hole 53 of the cylinder head 7, the internal volume in the fuel pressurizing chamber 23 increases. As a result, the fuel sucked into the fuel gallery chamber 19 of the supply pump from the feed pump is caused by the lowering of the plunger 8, the fuel supply passage 41 → the fuel supply passage 42 → the fuel supply passage 43 → the valve passage hole 45 → the valve. The fuel is introduced into the fuel pressurizing chamber 23 via the storage chamber 46 → the plurality of first through holes 66 → the plurality of second through holes 76.

When energization of the electromagnet coil is performed (ON) at the timing when the plunger 8 moves from the descending position to the ascending position in the cylinder hole 53 of the cylinder head 7, an electromagnetic force is generated in the electromagnet coil, and the armature A plurality of magnetic bodies such as 31 and a stator are magnetized. As a result, the armature 31 is attracted by the electromagnet attracting portion, and the spool valve 2 is moved in the valve closing operation direction and seated on the valve seat 4 of the valve body 3. As a result, the valve flow path hole 45 of the electromagnetic valve 1 is closed (fully closed) by the spool valve 2.
Further, when the plunger 8 further moves up in the cylinder hole 53 of the cylinder head 7, the internal volume in the fuel pressurizing chamber 23 becomes narrower.

  As a result, the fuel introduced into the fuel pressurizing chamber 23 is pressurized and increased in pressure as the plunger 8 rises. At this time, when the fuel pressure in the fuel pressurizing chamber 23 becomes higher than the valve opening pressure of the discharge valve 26, the discharge valve 26 opens, and the fuel pressurization chamber 23 opens to the fuel discharge passage 25 → the discharge valve 26 → the outlet pipe. The high pressure fuel is pumped and supplied to the common rail via the 27 discharge ports 29. After the high pressure fuel is pumped, the energization of the coil of the solenoid valve 1 is stopped (OFF), the spool valve 2 returns to the valve fully open position, and the fuel is sucked into the fuel pressurizing chamber 23 again.

  Here, the amount of fuel discharged from the supply pump into the common rail is determined based on the actual intake period during which fuel is sucked into the fuel pressurizing chamber 23 by controlling the energization timing and energization period of the coil of the solenoid valve 1 by the ECU. And the amount of fuel sucked into the fuel pressurizing chamber 23 when the plunger 8 descends in the cylinder hole 53 of the cylinder head 7 can be controlled. As a result, the common rail pressure corresponding to (or corresponding to) the injection pressure of the fuel injected into the combustion chamber of each cylinder of the engine from the injector mounted corresponding to each cylinder of the engine corresponds to the engine operating conditions. It becomes possible to control to the optimum value.

[Effect of Example 1]
As described above, in the supply pump of this embodiment, the valve stoppers that regulate the valve lift amount of the solenoid valve 1 are overlapped in surface contact with each other in the direction in which the screw tightening axial force of the solenoid valve 1 acts. The first and second plate-like stoppers 5 and 6 are constituted by the first and second plate-like stoppers 5 and 6, and the valve body 3 of the electromagnetic valve 1 is made by the screw tightening axial force of the electromagnetic valve 1. The solenoid valve contact surface 52 and the cylinder contact surface 57 of the cylinder 9 of the cylinder head 7 are held and fixed. That is, the two first and second plate-like stoppers 5 and 6 are connected to the solenoid valve contact surface 52 of the valve body 3 of the solenoid valve 1 and the cylinder 9 of the cylinder 9 of the cylinder head 7 by the screw tightening axial force of the solenoid valve 1. It is held and fixed in a state of being sandwiched between the contact surface 57.

Thereby, the screw tightening axial force of the solenoid valve 1 causes the solenoid valve contact surface 52 of the valve body 3 of the solenoid valve 1 and the first contact surface 62 of the first stopper corner portion 61 of the first plate-like stopper 5 to be liquid. In order to closely adhere, a first seal portion having a high-pressure fuel seal function is formed between the solenoid valve contact surface 52 of the solenoid valve 1 and the first contact surface 62 of the first plate-like stopper 5. Further, the second contact surface 72 of the second stopper corner 71 of the second plate-like stopper 6 and the cylinder contact surface 57 of the cylinder 9 of the cylinder head 7 are liquid-tight by the screw tightening axial force of the solenoid valve 1. In order to adhere, a second seal portion having a high-pressure fuel seal function is formed between the second contact surface 72 of the second plate-like stopper 6 and the cylinder contact surface 57 of the cylinder head 7.
As a result, in the supply pump of this embodiment, the first and second seal portions can ensure high-pressure sealability that can cope with the recent increase in fuel injection pressure.

  Further, in the supply pump of the present embodiment, the number of sliding portions in the valve stopper can be increased by increasing the valve stopper from the current one to two. Thereby, it is possible to reduce the relative slip amount between the solenoid valve contact surface 52 of the valve body 3 of the solenoid valve 1 and the first contact surface 62 of the first stopper corner portion 61 of the first plate-like stopper 5. Become. In addition, the relative slip amount between the second contact surface 72 of the second stopper corner 71 of the second plate-like stopper 6 and the cylinder contact surface 57 of the cylinder 9 of the cylinder head 7 can be reduced.

  Accordingly, fretting wear at the first seal portion between the solenoid valve contact surface 52 of the valve body 3 of the solenoid valve 1 and the first contact surface 62 of the first plate-like stopper 5 can be suppressed. Further, fretting wear at the second seal portion between the second contact surface 72 of the second plate-like stopper 6 and the cylinder contact surface 57 of the cylinder 9 of the cylinder head 7 can be suppressed. As a result, wear powder does not accumulate on the first and second seal portions, and no large frictional force is generated between the contact surfaces of the first and second seal portions. In addition, the stress concentration due to contact stress at the time of fretting wear and the occurrence of stress concentration due to the accumulation of wear powder generated by fretting wear and partial bulging and a strong one-contact state can be suppressed. it can.

Accordingly, a phenomenon that the sealing performance of the first and second sealing portions is deteriorated and the valve body 3 of the electromagnetic valve 1 or the two first and second plate-like stoppers 5 and 6 or the cylinder 9 of the cylinder head 7 is fatigued. The occurrence of (fretting fatigue) can be suppressed. Thus, no high-pressure fuel leaks from the inside of the valve accommodating chamber 46 or the fuel pressurizing chamber 23 to the low-pressure side fuel supply passages 42 and 43 via the first seal portion or the second seal portion. . That is, since the occurrence of fretting wear in the first and second seal portions can be suppressed, fuel leakage from the first and second seal portions can be prevented. In addition, problems such as fatigue failure from the wear surface of the valve body 3 of the electromagnetic valve 1 and the first plate-like stopper 5 and the wear surface of the second plate-like stopper 6 and the cylinder 9 of the cylinder head 7 are eliminated. Can do .

[Example 2]
FIG. 4 shows a second embodiment of the present invention, FIG. 4 (a) shows the main part of the supply pump, and FIG. 4 (b) shows the first plate-like stopper.

The two first and second plate-like stoppers 5 and 6 of the present embodiment have two first and second annular grooves at the abutting portions of the plurality of first through holes 66 and the plurality of second through holes 76. (Recesses) 67 and 77 are provided.
The first annular groove 67 is provided on the first contact surface 64 of the first plate-like stopper 5 so as to surround the periphery of the first through hole 65, and from the first contact surface 64 to the upper side (valve body side) in the drawing. It is arranged so as to be recessed. An annular first communication chamber 69 that communicates the plurality of first through holes 66 and the plurality of second through holes 76 is formed inside the first annular groove 67. The first annular groove 67 connects all the first through holes 66 among the plurality of first through holes 66 and all the second through holes 76 among the plurality of second through holes 76. Are provided in an annular shape. Thereby, even if one first through-hole 66 of the plurality of first through-holes 66 is blocked by a foreign substance or the like, or the remaining first through-hole 66 is left leaving one first through-hole 66. Even if the hole 66 is blocked by foreign matter or the like, it is possible to suppress a decrease in fuel flowability.

  The second annular groove 77 is provided on the second contact surface 74 of the second plate-like stopper 6 so as to surround the periphery of the second through hole 75, and is recessed from the second contact surface 74 to the lower side (cylinder side) in the figure. It is arranged like this. An annular second communication chamber 79 that communicates the plurality of first through holes 66 and the plurality of second through holes 76 is formed inside the second annular groove 77. The second annular groove 77 connects all the first through holes 66 among the plurality of first through holes 66 and all the second through holes 76 among the plurality of second through holes 76. Are provided in an annular shape. Thereby, even if one second through-hole 76 of the plurality of second through-holes 76 is blocked by a foreign substance or the like, or the remaining second through-hole 76 is left leaving one second through-hole 76. Even if the hole 76 is blocked by foreign matter or the like, it is possible to suppress a decrease in the flowability of fuel.

The fuel supply passages 41 to 43, particularly the fuel supply passage 43 formed inside the valve body of the solenoid valve 1, include a valve passage hole 45, a valve accommodating chamber 46, a plurality of first through holes 66, and a first communication. The chamber 69, the second communication chamber 79, and the plurality of second through holes 76 communicate with a cylinder hole (particularly the fuel pressurizing chamber 23) formed in the cylinder of the cylinder head 7.
In addition, the groove width (groove width in the radial direction) of the two first and second annular grooves 67 and 77 is larger than the hole diameters of the first and second through holes 66 and 76. In this embodiment, the first and second annular grooves 67 and 77 are provided on both end surfaces of the first and second contact surfaces 64 and 74 of the two first and second plate-like stoppers 5 and 6. However, an annular groove may be provided only on the first contact surface 64 of the first plate-like stopper 5, and an annular groove is provided only on the second contact surface 74 of the second plate-like stopper 6. Also good .

Example 3
FIG. 5 shows a third embodiment of the present invention, FIG. 5 (a) shows the main part of the supply pump, and FIG. 5 (b) shows the first plate-like stopper.

  The two first and second plate-like stoppers 5 and 6 of the present embodiment have two first and second circular grooves at the abutting portions of the plurality of first through holes 66 and the plurality of second through holes 76. (Recesses) 91 and 92 are provided. In these first and second circular grooves 91 and 92, circular first rings having functions similar to those of the first and second communication chambers 69 and 79 in the first and second annular grooves of the second embodiment are provided. 1 and second communication chambers 93 and 94 are formed.

The fuel supply passages 41 to 43, particularly the fuel supply passage 43 formed inside the valve body of the solenoid valve 1, include a valve passage hole 45, a valve accommodating chamber 46, a plurality of first through holes 66, and a first communication. The chamber 93, the second communication chamber 94, and the plurality of second through holes 76 communicate with a cylinder hole (particularly the fuel pressurizing chamber 23) formed in the cylinder of the cylinder head 7.
The first and second communication chambers 93 and 94 are also communicated with the first and second through holes 65 and 75. In this embodiment, the first and second circular grooves 91 and 92 are provided on both end surfaces of the first and second contact surfaces 64 and 74 of the two first and second plate-like stoppers 5 and 6. However, a circular groove may be provided only on the first contact surface 64 of the first plate-like stopper 5, and a circular groove is provided only on the second contact surface 74 of the second plate-like stopper 6. Also good .

[Reference Example 1]
FIG. 6 shows a reference example 1 of the present invention and is a diagram showing a main part of a supply pump.

The second plate-like stopper 6 of the present reference example eliminates the second through holes 75 and 76 of the first to third embodiments, and includes one of the first through holes 65 and the plurality of first through holes 66. A circular communication chamber 95 communicating with all the first through holes 65 and 66 is provided.
The fuel supply passages 41 to 43, particularly the fuel supply passage 43 formed inside the valve body of the electromagnetic valve 1, includes a valve passage hole 45, a valve storage chamber 46, a plurality of first through holes 66, and a communication chamber 95. The cylinder head 7 communicates with a cylinder hole (particularly the fuel pressurizing chamber 23) formed in the cylinder.

Example 4
FIG. 7 shows Embodiment 4 of the present invention, and FIGS. 7A and 7B show the main part of the supply pump.

The two first and second plate-like stoppers 5 and 6 of the present embodiment eliminate the first and second stopper corner portions 61 and 71 and are the outermost of the first and second plate-like stoppers 5 and 6. The first and second stopper side contact portions 60 and 70 are formed in a planar shape up to the corner (edge portion) where the outer wall surface provided on the radial side and both end surfaces in the plate thickness direction intersect. .
The first stopper side contact portion 60 is a ring-shaped contact surface (first contact surface of the first plate-like stopper 5) which comes into surface contact with the solenoid valve contact surface 52 of the valve body 3 of the solenoid valve 1 and is liquid-tightly adhered. 62). The first contact surface 62 surrounds the plurality of first through holes 66 and the first plate-like stopper 5 so as to surround the plurality of first through holes 66 arranged at equal intervals in the circumferential direction. It is formed between the wall surface (maximum outer diameter part). Further, the first stopper side contact portion 60 reduces the contact area between the solenoid valve contact surface 52 of the valve body 3 of the solenoid valve 1 and the first contact surface 62 of the first plate-like stopper 5, so that the solenoid valve 1. An annular (or partial annular) first concave portion 96 is formed for improving the sealing surface pressure between the electromagnetic valve contact surface 52 and the first contact surface 62 of the first plate-like stopper 5.

  The second stopper-side contact portion 70 is an annular contact surface (second contact surface of the second plate-like stopper 6) that comes into surface contact with the cylinder contact surface 57 of the cylinder 9 of the cylinder head 7 and is in liquid-tight contact. 72). The second contact surface 72 surrounds the plurality of second through holes 76 and the second plate-like stopper 6 so as to surround the periphery of the plurality of second through holes 76 arranged at equal intervals in the circumferential direction. It is formed between the wall surface (maximum outer diameter part). Further, the contact area between the second contact surface 72 of the second plate-like stopper 6 and the cylinder contact surface 57 of the cylinder head 7 is reduced in the second stopper-side contact portion 70, and the second plate-like stopper 6 has a second contact area. An annular (or partial annular) second concave portion 97 for improving the seal surface pressure between the two contact surface 72 and the cylinder contact surface 57 of the cylinder head 7 is formed.

  As described above, in the supply pump of the present embodiment, in addition to the configurations of the first and second embodiments, the first and second stopper side contacts of the two first and second plate-like stoppers 5 and 6 are provided. The parts 60 and 70 are formed in a planar shape up to the corner (edge part). Further, the annular convex portion (solenoid valve contact portion) 51 of the valve body 3 of the electromagnetic valve 1 does not protrude beyond the edge portion of the first plate-like stopper 5 in the radial direction. As a result, when the solenoid valve 1 is screwed to the inner periphery of the cylindrical portion 10 of the cylinder head 7, the screw tightening axial force of the solenoid valve 1 causes the solenoid valve contact surface 52 of the annular projection 51 of the solenoid valve 1. And the first contact surface 62 of the first stopper-side contact portion 60 of the first plate-like stopper 5 makes it difficult for the edge portion of the first plate-like stopper 5 to deform, and the annular shape of the solenoid valve 1 It becomes difficult for the convex part 51 to deform | transform into the outer-diameter side of a radial direction.

  Therefore, the first seal portion formed by the electromagnetic valve contact surface 52 of the electromagnetic valve 1 and the first contact surface 62 of the first plate-like stopper 5 has a high pressure as the fuel pressure in the valve storage chamber 46 changes. Even when a low pressure is repeatedly applied, the annular convex portion 51 of the electromagnetic valve 1 is prevented from being deformed radially outward, and the deformation of the annular convex portion 51 of the electromagnetic valve 1 is prevented from returning. can do. For this reason, a minute repeated relative slip accompanied by a frictional force is less likely to occur between the electromagnetic valve contact surface 52 of the electromagnetic valve 1 and the first contact surface 62 of the first plate-like stopper 5. Fretting wear at the part can be suppressed.

  As a result, wear powder does not accumulate on the first seal portion, and no large frictional force is generated between the contact surfaces of the first seal portion. In addition, the stress concentration due to contact stress at the time of fretting wear and the occurrence of stress concentration due to the accumulation of wear powder generated by fretting wear and partial bulging and a strong one-contact state can be suppressed. it can. Therefore, it is possible to suppress the deterioration of the sealing performance of the first seal portion and the occurrence of a phenomenon (fretting fatigue) leading to fatigue failure of the valve body 3 of the electromagnetic valve 1 or the first plate-like stopper 5. This prevents the high-pressure fuel from leaking from the inside of the valve housing chamber 46 to the low-pressure side fuel supply passages 42 and 43 via the first seal portion.

In the supply pump of this embodiment, the first and second concave portions 96 and 97 are respectively connected to the first and second stopper side contact portions 60 and 70 of the two first and second plate-like stoppers 5 and 6. Is provided. Thereby, the contact area (seal area) between the electromagnetic valve contact surface 52 of the electromagnetic valve 1 and the first contact surface 62 of the first plate-like stopper 5 can be reduced, and the second plate-like stopper 6 has the second area. The contact area (seal area) between the contact surface 72 and the cylinder contact surface 57 of the cylinder head 7 can be reduced.
Accordingly, the seal surface pressure at the two first and second seal portions can be improved with a small screw tightening axial force by reducing the seal area. The high-pressure fuel does not leak from the inside to the low-pressure side fuel supply passages 42 and 43 via the first and second seal portions. Therefore, it is possible to improve the seal surface pressure against the recent increase in fuel injection pressure.

[Example 5, Reference Example 2]
FIG. 8 (a) shows a fifth embodiment of the present invention , FIG. 8 (b) shows a reference example 2 of the present invention , and FIGS. 8 (a) and 8 (b) show the main part of the supply pump. It is a figure.

In this embodiment and the reference example , the first and second plate-like stoppers 5 and 6 of the embodiment 3 and the reference example 1 are provided with the first and second stopper side contact portions 60 and 70 of the embodiment 4 , and further, 1. First and second concave portions 96 and 97 are provided on the second stopper side contact portions 60 and 70, respectively.

Example 6
FIG. 9 shows a sixth embodiment of the present invention, and FIGS. 9A and 9B show the main part of the supply pump.

As shown in FIG. 9A, the two first and second plate-like stoppers 5 and 6 of this embodiment eliminate the first and second concave portions 96 and 97, and each first and second stoppers. First and second stopper sides formed in a planar shape up to the corner (edge) where the outer wall surface provided on the outermost diameter side of the two plate-like stoppers 5 and 6 and both end faces in the thickness direction intersect Contact portions 60 and 70 are provided.
Further, in the supply pump of the present embodiment, as shown in FIG. 9B, the stepped portion 56 between the opening end of the cylinder hole 53 of the cylinder 9 of the cylinder head 7 and the plate accommodation hole 55 has a An annular relief groove 99 is provided so as to surround the periphery of the cylinder contact surface 57 that comes into surface contact with the second contact surface 72 of the two-plate stopper 6 and comes into liquid tight contact therewith.

Accordingly, the second seal portion formed by the second contact surface 72 of the second plate-like stopper 6 and the cylinder contact surface 57 of the cylinder head 7 is increased in pressure with the change in the fuel pressure in the fuel pressurizing chamber 23. Even if the low pressure repeatedly acts, a slight relative slip occurs between the corner (edge portion) of the second stopper side contact portion 70 of the second plate-like stopper 6 and the cylinder contact surface 57 of the cylinder head 7. There is nothing, and fretting wear at the second seal portion can be suppressed. In addition, it is possible to prevent a phenomenon (fretting fatigue) leading to fatigue failure of the second plate-like stopper 6 due to local stress concentration on the edge portion of the second stopper-side contact portion 70 of the second plate-like stopper 6. it can.
As a result, the screw tightening axial force of the solenoid valve 1 does not decrease at the fretting operation position, and the fuel pressurizing chamber 23 passes through the second seal portion to the low pressure side fuel supply passages 42 and 43. No high-pressure fuel leaks occur. The escape groove 99 may be provided in the annular convex portion 51 of the valve body 3 of the electromagnetic valve 1. In this case, stress concentration on the edge portion of the first plate-like stopper 5 can be prevented.

[Modification]
In this embodiment, an example in which the fuel supply pump of the present invention is applied to a supply pump used in a common rail fuel injection system has been described. However, the fuel supply pump of the present invention is used in a fuel injection device for an internal combustion engine. The present invention may be applied to a distributed fuel injection pump or a row fuel injection pump. The number of cam peaks of the cam 13 in FIG. 1 may be an arbitrary number of one or more. The number of pump elements, that is, the number of plungers and cylinders may be one or two or more, and the number is arbitrary. The number of solenoid valves 1 may be one or two or more depending on the number of pump elements, and the number is arbitrary.

  In the present embodiment, the feed pump is connected upstream of the supply pump suction port in the fuel flow direction. However, the camshaft 12 rotates along with the rotation of the crankshaft of the engine. A feed pump that pumps low-pressure fuel through the pump suction port may be built in the pump housing 11 of the supply pump.

  In the present embodiment, the valve stopper that regulates the valve lift amount of the solenoid valve 1 is used as the direction in which the screw tightening axial force of the solenoid valve 1 acts, the axial direction of the valve body 3 of the solenoid valve 1, or the cylinder head 7. The first and second plate-like stoppers 5 and 6 are stacked in liquid-tight surface contact with each other in the axial direction of the cylinder 9, and the valve stopper has a screw tightening axial force of the solenoid valve 1. Consists of a plurality of (three or more) plate members stacked in liquid-tight surface contact with each other in the acting direction, the axial direction of the valve body 3 of the electromagnetic valve 1, or the axial direction of the cylinder 9 of the cylinder head 7. You may do it. A plurality of plate members are stacked in the direction in which the screw tightening axial force of the electromagnetic valve 1 acts, the axial direction of the valve body 3 of the electromagnetic valve 1, or the axial direction of the cylinder 9 of the cylinder head 7. May be configured.

It is sectional drawing which showed the supply pump (Example 1). It is sectional drawing which showed the principal part of the supply pump (Example 1). It is sectional drawing which showed the principal part of the supply pump (Example 1). (A) is the figure which showed the principal part of the supply pump, (b) is AA sectional drawing of (a) (Example 2). (A) is the figure which showed the principal part of the supply pump, (b) is BB sectional drawing of (a) (Example 3). It is sectional drawing which showed the principal part of the supply pump ( reference example 1 ). (A), (b) is the figure which showed the principal part of the supply pump (Example 4 ). (A), (b) is the figure which showed the principal part of the supply pump (Example 5, Reference example 2 ). (A), (b) is the figure which showed the principal part of the supply pump (Example 6 ). It is sectional drawing which showed the principal part of the supply pump (conventional technique). (A) is the figure which showed the principal part of the supply pump, (b) is the top view which showed the stopper (conventional technique). (A), (b) is explanatory drawing which showed the generation | occurrence | production situation of fretting wear (conventional technique).

1 Solenoid valve 2 Spool valve (solenoid valve)
3 Valve body 5 First plate-like stopper (stopper, plate member)
6 Second plate stopper (stopper, plate member)
7 Cylinder head 8 Plunger 9 Cylinder 23 Fuel pressurizing chamber 41 Fuel supply passage (fuel passage)
42 Fuel supply passage (fuel passage)
43 Fuel supply passage (fuel passage)
45 Valve passage hole (fuel passage)
46 Valve storage chamber 51 Annular convex part (solenoid valve contact part)
52 Solenoid valve contact surface 53 of the valve body Cylinder hole 56 Cylinder stepped portion 57 Cylinder contact surface 62 First contact surface 64 of the first plate-like stopper First contact surface 65 of the first plate-like stopper First plate 1st through-hole 66 of the first stopper The first through-hole 67 of the first plate-like stopper The first annular groove (recess) of the first plate-like stopper
69 First communication chamber 72 of the first plate-shaped stopper Second contact surface 74 of the second plate-shaped stopper Second contact surface 75 of the second plate-shaped stopper Second through hole 76 of the second plate-shaped stopper Second plate-shaped stopper The second through-hole 77 of the second annular groove (concave portion) of the second plate-like stopper
79 Second communication chamber 91 of second plate-shaped stopper 91 First circular groove (concave portion) of first plate-shaped stopper
92 Second circular groove (recess) of second plate-like stopper
93 First plate-like stopper first communication chamber 94 Second plate-like stopper second communication chamber 95 Second plate-like stopper communication chamber 96 First plate-like stopper first concave portion 97 Second plate-like stopper second 2-concave part 99 Cylinder relief groove

Claims (5)

(A) a pump body having a cylinder in which a cylinder hole for slidably receiving a plunger is formed;
(B) an electromagnetic valve having a valve disposed on one side in the axial direction of the pump main body with respect to the cylinder hole and opening and closing a fuel passage communicating with the cylinder hole;
(C) In a fuel supply pump provided with a stopper disposed between the cylinder and the solenoid valve to regulate a valve lift amount of the solenoid valve,
The stopper is composed of a plurality of plate members stacked in surface contact with each other,
The plurality of plate members are sandwiched and fixed between the cylinder and the solenoid valve ,
The plurality of plate members are constituted by at least two first and second plate members,
The first plate member has a first contact surface that is superimposed on one end surface in the plate thickness direction of the second plate member and is in surface contact with the contact surface of the electromagnetic valve,
The second plate member has a second contact surface that is superimposed on the other end surface in the plate thickness direction of the first plate member and is in surface contact with and closely contacts the contact surface of the cylinder,
The first plate member has a first through hole communicating with both end faces in the plate thickness direction,
The second plate member has a second through hole communicating with both end faces in the plate thickness direction,
The fuel passage communicates with the cylinder hole via the first through hole and the second through hole,
The first through hole is composed of a plurality of first through holes penetrating the first plate member,
The second through hole is composed of a plurality of second through holes penetrating the second plate member,
Each of the plurality of second through holes communicates with each first through hole of the plurality of first through holes . (A) a pump body having a cylinder in which a cylinder hole for slidably receiving a plunger is formed;
(B) an electromagnetic valve having a valve disposed on one side in the axial direction of the pump main body with respect to the cylinder hole and opening and closing a fuel passage communicating with the cylinder hole;
(C) a stopper disposed between the cylinder and the solenoid valve for regulating a valve lift amount of the solenoid valve;
In a fuel supply pump with
The stopper is composed of a plurality of plate members stacked in surface contact with each other,
The plurality of plate members are sandwiched and fixed between the cylinder and the solenoid valve,
The plurality of plate members are constituted by at least two first and second plate members,
The first plate member has a first contact surface that is superimposed on one end surface in the plate thickness direction of the second plate member and is in surface contact with the contact surface of the electromagnetic valve,
The second plate member has a second contact surface that is superimposed on the other end surface in the plate thickness direction of the first plate member and is in surface contact with and closely contacts the contact surface of the cylinder,
The first plate member has a first through hole communicating with both end faces in the plate thickness direction,
The second plate member has a second through hole communicating with both end faces in the plate thickness direction,
The fuel passage communicates with the cylinder hole via the first through hole and the second through hole,
The first through hole is composed of a plurality of first through holes penetrating the first plate member,
The second through hole is composed of a plurality of second through holes penetrating the second plate member,
In the first plate member and the second plate member, a communication chamber that connects the first through hole and the second through hole is formed at a butt portion between the first through hole and the second through hole. A fuel supply pump having a concave portion . The fuel supply pump according to claim 2, wherein
The other end surface in the plate thickness direction of the first plate member constitutes a first contact surface that is in surface contact with and closely contacts the second plate member,
One end surface of the second plate member in the plate thickness direction constitutes a second contact surface that is in surface contact with and closely contacts the first contact surface;
The fuel supply pump , wherein the recess is formed in the first contact surface or the second contact surface . The fuel supply pump according to claim 2 or claim 3 ,
The recess is provided to connect all the first through holes of the plurality of first through holes and all the second through holes of the plurality of second through holes. Fuel supply pump. The fuel supply pump according to any one of claims 1 to 4 ,
A fuel supply pump, wherein the first contact surface or the second contact surface is provided with a concave portion for reducing a contact area with the contact surface of the electromagnetic valve or the contact surface of the cylinder. .

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