JP5792589B2 - Pressure control device and fuel supply device - Google Patents

Description

  The present invention relates to a pressure control device and a fuel supply device including the same.

  2. Description of the Related Art Conventionally, a fuel supply device for an internal combustion engine mounted on a vehicle has a pressure for adjusting the fuel supply pressure to the fuel consumption unit when the fuel stored in the fuel tank is supplied to the fuel consumption unit by a fuel pump. A control device is provided. The pressure control device regulates the fuel supply pressure from the fuel pump that pumps up the fuel in the fuel tank to the injector constituting the fuel consumption unit.

  Such a pressure control device generally divides the inside of a housing into two chambers by a diaphragm, and uses the displacement of the central portion of the diaphragm in accordance with the fuel pressure in the pressure adjusting chamber on one surface side of the diaphragm. The valve is displaced in the valve opening direction and the valve closing direction. In addition, such a pressure control device maintains the valve opening state of the pressure regulating valve body so that the fuel pressure in the pressure regulating chamber reaches the set pressure by suppressing the displacement of the diaphragm by a coil spring on the other surface side of the diaphragm. It has a configuration.

  As this type of pressure control device, for example, a diaphragm that divides the inside of the housing into two chambers, a fluid introduction port that is located on one surface side of the diaphragm and into which pressurized fuel from a fuel pump is introduced, and excess fuel are discharged. A pressure chamber having a discharge port, a back pressure chamber located on the other surface side of the diaphragm, into which a back pressure fluid is introduced, and slidably provided in the housing, and an atmospheric pressure between the diaphragm and the back pressure chamber. A plunger that forms an open chamber, a valve member that is attached to the diaphragm so as to open and close the discharge port according to the displacement of the diaphragm, and a valve member that is interposed between the diaphragm and the plunger in the valve opening direction. 2. Description of the Related Art There is known a pressure regulator having a spring to be energized and a stopper means for defining a movable range of a plunger, that is, a fuel pressure control valve. And in the pressure control apparatus provided with this fuel pressure control valve, the set value is switched between the low pressure value and the high pressure value by switching the set load of the spring in two stages depending on whether or not the back pressure fluid is supplied ( For example, see Patent Document 1).

  Further, as a conventional fuel supply device, a device including a pressure control device that switches a fuel pressure in a pressure adjusting chamber between a low pressure and a high pressure depending on whether or not a back pressure fluid is supplied to the back pressure chamber is known (for example, a patent) Reference 2). This fuel supply device has a fuel pump for supplying fuel in a fuel tank to an engine, a pressure regulating chamber and a back pressure chamber defined by a movable partition wall, and a part of the fuel boosted by the fuel pump is introduced. A pressure regulator that adjusts the fuel pressure in the regulated pressure chamber according to the pressure in the back pressure chamber and discharges excess fuel in the pressure regulating chamber from the pressure regulating discharge passage, and regulates the pressure to the movable wall A communication passage that connects the chamber and the back pressure chamber, a back pressure discharge passage that discharges fuel in the back pressure chamber, a fuel switching valve that opens and closes the back pressure discharge passage, and a back pressure by the fuel switching valve. The fuel pressure supplied to the injector is variable by opening and closing the discharge passage.

  In the fuel supply device disclosed in Patent Document 2, the fuel introduced into the pressure regulating chamber of the pressure control device is introduced into the back pressure chamber through the communication passage of the movable partition wall, so that the piping related to the back pressure chamber introduction passage Can be omitted, and the responsiveness when changing the fuel pressure can be improved.

  Here, as a conventional fuel switching valve applied to the fuel supply apparatus, for example, the one shown in FIG. 11 is known. A fuel switching valve 100 shown in FIG. 11 includes a bobbin 101, an electromagnetic coil 102, a valve 103, a coil spring 104, a shield 105, and a stator core 106.

  The bobbin 101 is made of a synthetic resin and includes a bobbin part 110, a cylinder part 111, and a fuel pipe part 112. The bobbin portion 110 has an electromagnetic coil 102 wound around the outside and a coil spring 104 accommodated inside. The cylinder part 111 is formed continuously with the bobbin part 110, and a valve 103 is accommodated in the cylinder part 111 so as to be able to reciprocate. The fuel pipe part 112 is formed at the end of the cylinder part 111 and is opened with the fuel inflow pipe 112a to which the fuel is supplied, the fuel outflow pipe 112b from which the fuel is discharged, and the inside of the cylinder part 111 facing. And an open end 112c of the fuel outflow pipe 112b.

  The valve 103 is made of a substantially cylindrical magnetic body, and a seal portion 114 is provided on one end surface. When the valve 103 is moved by the cylinder portion 111 and the seal portion 114 is pressed against the opening end portion 112c, the communication between the fuel inflow pipe 112a and the fuel outflow pipe 112b is blocked. The coil spring 104 urges the valve 103 in a direction to close the communication between the fuel inflow pipe 112a and the fuel outflow pipe 112b. The coil spring 104 uses a cylindrical and equally spaced coil spring and has a linear load-deflection characteristic (hereinafter also simply referred to as a spring characteristic).

  As shown in FIG. 11A, when the electromagnetic coil 102 is not energized, the valve 103 blocks the communication between the fuel inflow pipe 112a and the fuel outflow pipe 112b by the bias of the coil spring 104. Therefore, the fuel that has flowed into the fuel inflow pipe 112a is stopped by the valve 103 as indicated by the arrow in the figure.

  On the other hand, as shown in FIG. 11B, when the electromagnetic coil 102 is energized, the valve 103 is attracted by the electromagnetic coil 102 against the coil spring 104, and the valve 103 is in contact with the fuel inflow pipe 112a and the fuel outflow pipe. 112b is communicated. Therefore, the fuel that has flowed into the fuel inflow pipe 112a is discharged from the fuel outflow pipe 112b through the cylinder portion 111 as indicated by the arrow in the figure.

  Further, in an ECU (Electronic Control Unit) of a vehicle equipped with a fuel supply device, a time lag from when a voltage is applied to the electromagnetic coil 102 of the fuel switching valve 100 to when the fuel supply pressure to the fuel consumption unit is actually changed. Is calculated. As a result, the ECU applies the voltage to the electromagnetic coil 102 earlier by the time lag than when attempting to obtain a desired fuel supply pressure at the fuel consuming unit.

JP 2009-144686 A JP 2010-255458 A

  However, in the conventional fuel supply device, the responsiveness of the valve 103 is lowered due to the linear load-deflection characteristic of the coil spring 104 and the influence of the delay in the response of the electromagnetic force due to the inductance of the electromagnetic coil 102. There is a problem that it takes a long time to complete the switching of the valve 103.

  If the switching time of the valve 103 becomes longer, the time lag from when the voltage is applied to the electromagnetic coil 102 to when the fuel supply pressure to the fuel consuming part is actually changed becomes longer, and the time lag error increases and the time lag increases. There has been a problem that the calculation accuracy of is reduced. In addition, if the time lag calculation accuracy decreases in this way, the load for driving the fuel pump increases, and the setting accuracy of the fuel supply pressure to the fuel consumption section decreases, and fuel is supplied at a pressure different from the original set value. There is a problem that it is difficult to improve fuel efficiency for these reasons.

  The present invention has been made to solve such a problem, and can improve the responsiveness at the time of changing the fuel pressure as compared with the prior art and improve the calculation accuracy of the switching time of the fuel supply pressure. Another object of the present invention is to provide a pressure control device and a fuel supply device that can improve fuel consumption.

  To achieve the above object, the pressure control device according to the present invention includes (1) a fuel pressure control valve that controls the pressure of the fuel to be controlled by switching the pressure of the operating pressure fuel, and a fuel switching valve that switches the pressure of the operating pressure fuel. The fuel switching valve includes a bobbin that forms a fuel flow part through which the operating pressure fuel flows, and a valve body that is reciprocally accommodated in the bobbin and that can open and close the fuel flow part by reciprocation. And an electromagnetic coil wound around the bobbin and attracting the valve body to a suction position, and an urging means housed inside the bobbin and returning the valve body from the suction position to the return position. In the apparatus, the urging means has a displacement amount of the valve body with respect to a change amount of a load acting on the valve body in a first displacement section from the return position to a predetermined displacement position. Displacement It characterized by having a greater non-linear characteristic than the displacement amount of the valve body with respect to the variation of load acting on the valve body in the second displacement section after between.

  With this configuration, when the valve body is moved from the return position to the suction position by the electromagnetic coil, the displacement amount of the valve body with respect to the amount of change in the load acting on the valve body is larger than that in the conventional case at least in the first displacement section. Therefore, the moving speed of the valve body can be improved.

  By improving the responsiveness of the valve body, the time lag from the time when the voltage is applied to the electromagnetic coil until the fuel supply pressure to the fuel consuming part is actually changed is shortened, the error of the time lag is reduced, and the time lag is reduced. Calculation accuracy can be improved.

  In addition, by improving the responsiveness of the valve body, the speed at which the fuel pressure of the fuel to be controlled is switched from, for example, a low pressure to a high pressure is increased. For this reason, the pump pressure can be rapidly increased from the low pressure to the high pressure, so that fuel efficiency can be improved.

  In the pressure control device according to the above (1), (2) another urging unit that is arranged in series with the urging unit and returns the valve body from the suction position to the return position is further provided. And the other biasing means is configured such that a displacement amount of the valve body with respect to a change amount of a load acting on the valve body in a third displacement section after the second displacement section is the valve in the second displacement section. It is larger than the displacement amount of the valve body with respect to the change amount of the load acting on the body.

  With this configuration, when the valve body moves from the suction position to the return position, the amount of displacement of the valve body with respect to the amount of change in the load acting on the valve body is increased at least in the third displacement section. The moving speed of the body can be improved. Therefore, when the valve element moves from the suction position to the return position, the movement time can be shortened.

  Thus, by improving the responsiveness of the valve body, the time lag from when the voltage is no longer applied to the electromagnetic coil until the fuel supply pressure to the fuel consuming part is actually changed is shortened, and the time lag error The accuracy of time lag calculation can be improved.

  In addition, by improving the responsiveness of the valve body, the speed at which the fuel pressure of the fuel to be controlled is switched from high pressure to low pressure, for example, is increased. For this reason, since the pump pressure can be quickly reduced from a high pressure to a low pressure, fuel consumption can be improved.

  In the pressure control device according to (2), (3) a flange projecting radially inward of the bobbin, a washer provided between the flange and the other biasing means, and the flange And a side surface portion constituting the bobbin for positioning the other urging means on the side opposite to the side, and the other urging means is accommodated inside the bobbin so as to have a predetermined initial load. It is characterized by that.

  With such a configuration, the urging unit and the other urging unit can be combined with a simple configuration, and the respective initial loads can be set.

  In the pressure control device according to (1) to (3) above, (4) the fuel pressure control valve includes a fluid introduction port through which the control target fuel is introduced, a fluid discharge port through which the control target fuel is discharged, and A housing having an operation pressure fuel introduction passage into which the operation pressure fuel is introduced; a pressure regulation chamber that communicates with the fluid introduction port and includes the operation pressure fuel introduction passage in the housing; and A partition-shaped pressure regulating member that communicates the fluid inlet and the fluid outlet according to the fuel pressure of the fuel, and the fuel pressure control valve introduces the operating pressure fuel into the operating pressure fuel introduction passage Thus, the area of the pressure receiving region where the pressure adjusting member receives the fuel pressure on one side is changed, and the fuel pressure in the pressure adjusting chamber is adjusted according to the area of the pressure receiving region. ,Previous The operation pressure fuel is enclosed in the operation pressure fuel introduction passage when the valve body is in the return position, and the operation pressure fuel is released from the operation pressure fuel introduction passage by moving the valve body from the return position to the suction position. Is preferred.

  With this configuration, the fuel pressure is regulated in two stages by making the area where the pressure regulating member receives the fuel pressure variable. Therefore, the fuel pressure supplied to the fuel consuming unit can be controlled in two stages without making the interior of the variable fuel pressure regulating valve into three chambers. For this reason, a fuel supply apparatus can be reduced in size.

  In addition, the fuel switching valve can switch whether or not the operating pressure fuel is introduced into the operating pressure fuel introduction passage by moving the valve body from one of the return position and the suction position to the other. Thus, the area of the pressure receiving region of the pressure regulating member can be easily changed. Therefore, the pressure of the fuel to be controlled by the fuel pressure control valve can be easily controlled.

  A fuel supply device for an internal combustion engine according to the present invention includes the pressure control device described in any one of (1) to (4) above, and (5) the control object supplied to a fuel consumption unit. The fuel pressure is regulated by the pressure control device.

  With this configuration, it is possible to shorten the speed at which the fuel pressure of the control target fuel supplied to the fuel consumption unit is switched between high pressure and low pressure. In particular, since the pump pressure can be quickly switched to a high pressure or a low pressure, fuel consumption can be improved.

  In the fuel supply device described in (5) above, (6) the fuel consumption unit is a fuel injection unit of an internal combustion engine. With this configuration, it is possible to shorten the time for switching the fuel pressure of the control target fuel supplied to the fuel injection unit between the high pressure and the low pressure.

  According to the present invention, the pressure control can improve the responsiveness at the time of changing the fuel pressure, improve the calculation accuracy of the switching time of the fuel supply pressure, and further improve the fuel consumption, as compared with the conventional case. An apparatus and a fuel supply device can be provided.

It is the schematic which shows the fuel supply apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the state which the fuel switching valve of the pressure control apparatus which concerns on the 1st Embodiment of this invention is obstruct | occluded, (a) is schematic and (b) is a schematic diagram which shows the pressure receiving area | region. . It is a figure which shows the state which the fuel switching valve of the pressure control apparatus which concerns on the 1st Embodiment of this invention is open | released, (a) is a schematic diagram, (b) is a schematic diagram which shows the pressure receiving area | region. . FIG. 4 is an urging unit according to the first embodiment of the present invention, wherein (a) is a side view of the first spring and (b) is a side view of the second spring. It is a characteristic view which shows the valve stroke with respect to the load of the 1st spring and 2nd spring which concern on the 1st Embodiment of this invention. It is sectional drawing which shows the fuel switching valve which concerns on the 1st Embodiment of this invention, (a) is the state of obstruction | occlusion at a bottom dead center, (b) and (c) are the states between obstruction | occlusion and open | release, d) is an open state at the top dead center. It is a time chart which shows operation | movement of the fuel supply apparatus which concerns on the 1st Embodiment of this invention. It is a time chart which shows operation | movement of the fuel supply apparatus which concerns on the 1st Embodiment of this invention, (a) is a voltage, (b) is an electric current, (c) is a position of a valve, (d) is a fuel pressure. Show. It is the schematic of the fuel switching valve which concerns on the 2nd Embodiment of this invention, and shows the state which has closed. It is a characteristic view which shows the valve stroke with respect to the load of the 1st spring and 2nd spring which concern on the 2nd Embodiment of this invention. It is the schematic which shows the conventional fuel switching valve, (a) shows a closed state, (b) shows an open state.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the present embodiment, the present invention is applied to a fuel supply device that supplies fuel to an internal combustion engine for a vehicle.

(First embodiment)
First, the configuration of a vehicle equipped with the fuel supply device will be described.

  As shown in FIG. 1, the vehicle 1 includes an internal combustion engine 2, a fuel supply device 3, and an ECU (Electronic Control Unit) 4.

  The internal combustion engine 2 is a multi-cylinder internal combustion engine mounted on an automobile, for example, a 4-cycle gasoline engine (hereinafter referred to as the engine 2). The engine 2 includes a plurality of cylinders 20, an intake port 21 corresponding to each cylinder 20, an injector 22 as a fuel consumption unit, and a delivery pipe 23. The injector 22 is provided, for example, with its end 22 a on the injection hole side exposed in the intake port 21 corresponding to each cylinder 20. The delivery pipe 23 is connected to each injector 22. Thereby, the delivery pipe 23 distributes the fuel from the fuel supply device 3 to the injectors 22.

  The fuel supply device 3 pumps and supplies fuel to the plurality of injectors 22 of the engine 2, and includes a fuel tank 30, a fuel pumping mechanism 31, and a pressure control device 32.

  The fuel tank 30 stores fuel consumed by the engine 2, for example, gasoline. The fuel tank 30 includes a sub tank 30a. A part of the fuel pumping mechanism 31 is disposed in the sub tank 30a. Here, in this specification, the fuel tank 30 is used in a general sense including the sub tank 30a. For example, the fuel stored in the fuel tank 30 includes the fuel stored in the sub tank 30a. And Further, the fuel tank 30 has a known jet pump (not shown) that introduces fuel into the sub-tank 30 a by the amount of fuel consumed successively by the engine 2.

  The fuel pumping mechanism 31 includes a fuel pump unit 40, a suction filter 41, a fuel filter 42, a check valve 43, a fuel pipe 44 connecting them, and a fuel pump controller (FPC) 45. The fuel pumping mechanism 31 pumps and supplies the fuel stored in the fuel tank 30 to the plurality of injectors 22 of the engine 2.

  The fuel pump unit 40 includes, for example, a fuel pump 40a having an impeller for pump operation, and a pump drive motor 40b that is a built-in DC motor that rotationally drives the fuel pump 40a. The fuel pump unit 40 is driven and stopped by controlling the energization of the pump drive motor 40b by the ECU 4 through the fuel pump controller 45.

  The fuel pump unit 40 is configured to be able to pump up fuel from the fuel tank 30 and pressurize it by driving a pump drive motor 40b. Further, the fuel pump unit 40 changes the rotational speed [rpm] of the pump drive motor 40b with respect to the same supply voltage according to the load torque, or the rotational speed of the pump drive motor 40b corresponding to the change in the supply voltage. Can be changed. As a result, the fuel pump unit 40 can change the discharge amount and discharge pressure per unit time.

  The suction filter 41 is provided at the suction port of the fuel pump unit 40 and prevents suction of foreign matter. The fuel filter 13 is provided at the discharge port of the fuel pump unit 40 and removes foreign matters in the discharged fuel.

  The check valve 43 is a check valve provided on the upstream side or the downstream side of the fuel filter 13. The check valve 43 opens in the fuel supply direction from the fuel pump unit 40 to the injector 22 side, while the check valve 43 is closed in the reverse flow direction of fuel from the injector 22 side to the fuel pump unit 40 side, and pressurized supply It is designed to prevent fuel backflow.

  The fuel pump controller 45 is provided in the upper part of the fuel tank 30. The fuel pump controller 45 is applied to the pump drive motor 40b of the fuel pump unit 40 in accordance with the deviation between the pump control signal from the ECU 4 and the detection signal of a voltage detector (not shown) that detects the terminal voltage of the pump drive motor 40b. The voltage to be controlled is controlled.

  The pressure control device 32 includes a fuel pressure control valve 50 and a fuel switching valve 70.

  As shown in FIG. 2A, the fuel pressure control valve 50 includes a housing 51, a pressure regulating member 52, a coil spring 53, an outer cylindrical member 54, and an inner cylindrical member 55. The fuel pressure control valve 50 controls the pressure of the fuel to be controlled (hereinafter also simply referred to as fuel) by switching the pressure of the operating pressure fuel. The control target fuel is fuel supplied from the fuel tank 30 and injected from the injector 22. The housing 51 is formed by caulking and joining a pair of concave first housing member 56 and second housing member 57 at their outer peripheral portions.

  The first housing member 56 includes a fluid introduction port 51a through which fuel is introduced, a fluid discharge port 51b through which the fuel is discharged, an operation pressure introduction hole 51c through which operation pressure fuel is introduced, and an operation pressure introduction hole 51c. And an operation pressure fuel introduction passage 65 through which operation pressure fuel is introduced. A space inside the first housing member 56 is partitioned by the pressure regulating member 52 to form a pressure regulating chamber 58. For this reason, the pressure regulating chamber 58 communicates with the fluid introduction port 51a and has an operation pressure fuel introduction passage 65.

  The second housing member 57 has at least one atmospheric pressure introduction hole 57a. A space inside the second housing member 57 is partitioned by the pressure adjusting member 52 to form a back pressure chamber 59. For this reason, the fluid introduction port 51 a, the fluid discharge port 51 b, and the operation pressure introduction hole 51 c are disposed on the pressure regulating chamber 58 side with respect to the pressure regulating member 52. The pressure adjusting member 52 causes the fluid inlet 51a and the fluid outlet 51b to communicate with each other in accordance with the fuel pressure in the pressure adjusting chamber 58.

  The pressure regulating member 52 is in the form of a partition wall and is sandwiched and supported by the first housing member 56 and the second housing member 57, and the interior of the housing 51 is divided into two chambers, a pressure regulating chamber 58 and a back pressure chamber 59. It is divided into. The pressure regulating member 52 is regulated at a degree of opening corresponding to the fuel pressure in the pressure regulating chamber 58 and a partition wall portion 60 forming a pressure regulating chamber 58 communicating with the fluid introduction port 51 a between the pressure regulating member 52 and the first housing 56. A movable valve body 61 that is displaced in the valve opening direction that allows the chamber 58 to communicate with the fluid discharge port 51b is integrally formed.

  The partition wall 60 is configured to constantly receive the fuel pressure in the pressure regulating chamber 58 on the first housing member 56 side. The partition wall portion 60 is formed of a flexible diaphragm formed by, for example, using a rubber layer that is not easily deteriorated against fuel as a base material layer, and laminating another rubber layer on the rubber layer, and integrally bonding them. The movable valve body 61 is formed of, for example, a metal disc-shaped valve body plate supported at the center of the partition wall 60.

  The coil spring 53 is provided in the back pressure chamber 59 so as to urge the movable valve body 61 toward the pressure regulating chamber 58, that is, in the valve closing direction.

  The outer cylindrical member 54 and the inner cylindrical member 55 are provided in the pressure regulating chamber 58. The outer cylindrical member 54 and the inner cylindrical member 55 have different diameters and are arranged concentrically with the moving direction of the movable valve body 61 as the axial direction. An end of the inner tubular member 55 on the movable valve body 61 side is a first valve seat 62. An end of the outer cylindrical member 54 on the movable valve body 61 side is a second valve seat portion 63.

  The first valve seat 62 has a discharge passage 64 communicating with the fluid discharge port 51b on the inner peripheral side thereof. The discharge passage 64 communicates with the fluid discharge port 51 b of the housing 51. The second valve seat portion 63 forms an operation pressure fuel introduction passage 65 between the second valve seat portion 63 and the first valve seat portion 62 on the inner peripheral side thereof. The operation pressure fuel introduction passage 65 communicates with the operation pressure introduction hole 51 c of the housing 51. The fuel that flows from the operation pressure fuel introduction passage 65 to the fuel switching valve 70 is used as the operation pressure fuel.

  The first housing member 56, the pressure adjusting member 52, and the outer cylindrical member 54 form an annular introduction side passage 66. The introduction side passage 66 introduces the fuel discharged from the fuel pump unit 40 from the fluid introduction port 51a, and causes the partition wall 60 to receive the fuel pressure.

  The fluid introduction port 51a of the housing 51 is connected to a fuel pipe 44, which is a circuit portion downstream of the check valve 43 of the fuel pumping mechanism 31, via a branch pipe 44a. The operation pressure introduction hole 51 c of the housing 51 is connected to the fuel switching valve 70.

  Here, as shown in FIG. 2A, when the fuel switching valve 70 is closed, the operating pressure fuel introduction passage 65 is closed, so that the operating pressure fuel pressure in the operation pressure fuel introduction passage 65 is introduced. It becomes equivalent to the side passage 66. In this case, as shown in FIG. 2 (b), the pressure receiving region of the pressure adjusting member 52 is an annular pressure receiving surface 52 a facing the introduction side passage 66 of the pressure adjusting member 52 and an annular pressure receiving surface facing the operation pressure fuel introduction passage 65. It becomes a region combined with the surface 52b.

  On the other hand, as shown in FIG. 3A, when the fuel switching valve 70 is in the open state, the operating pressure fuel introduction passage 65 is opened into the fuel tank 30, so that the operation pressure fuel in the operation pressure fuel introduction passage 65 is Is equal to the atmospheric pressure or the fuel in the fuel tank 30. In this case, as shown in FIG. 3B, the pressure receiving region of the pressure adjusting member 52 is only the annular pressure receiving surface 52 a facing the introduction side passage 66 of the pressure adjusting member 52.

  For this reason, the area of the pressure receiving region of the pressure regulating member 52 varies depending on whether the operation pressure fuel introduction passage 65 is closed or opened. When the area of the pressure receiving region of the pressure adjusting member 52 increases, the fuel pressure for opening the pressure adjusting member 52 against the urging force of the coil spring 53 can be reduced, so the fuel in the annular introduction side passage 66 can be reduced. The pressure regulation level decreases. Conversely, when the operating pressure fuel introduction passage 65 is opened in the fuel tank 30 and the area of the pressure receiving region of the pressure regulating member 52 is reduced, the pressure regulating member 52 is opened against the urging force of the coil spring 53. A large fuel pressure is required to achieve this. For this reason, the pressure regulation level of the fuel in the annular introduction side passage 66 is increased.

  As described above, the fuel pressure control valve 50 changes the area of the pressure receiving region where the pressure adjusting member 52 receives the fuel pressure on one side by introducing the operating pressure fuel into the operating pressure fuel introduction passage 65, and The fuel pressure in the pressure regulating chamber 58 is adjusted according to the area.

  The set pressure on the high-pressure side of the fuel pressure control valve 50 is a fuel pressure (usually 324 kPa as a gauge pressure) at which fuel vapor hardly occurs even when the fuel temperature in the delivery pipe 23 becomes high during warm-up or high fuel temperature. This is the setting value. The set pressure on the low pressure side of the fuel pressure control valve 50 is, for example, 200 kPa as a gauge pressure, and a fuel pressure set value at which fuel vapor hardly occurs when the fuel temperature in the delivery pipe 23 becomes relatively low during traveling. It has become.

  As shown in FIG. 2, the fuel switching valve 70 includes a bobbin 71, an electromagnetic coil 72, a valve 73, a first spring 76, a second spring 78, a shield 75, a stator core 77, a washer 79, The operation pressure fuel pressure is switched.

  The bobbin 71 is made of a synthetic resin, and includes a bobbin portion 80, a cylinder portion 81, and a fuel pipe portion 82 as a fuel circulation portion. The bobbin portion 80 has an electromagnetic coil 72 wound around the outside and a first spring 76 and a second spring 78 housed inside. The first spring 76 constitutes an urging means according to the present invention, and the second spring 78 constitutes another urging means according to the present invention. The cylinder portion 81 is formed continuously with the bobbin portion 80, and a valve 73 is accommodated in the cylinder portion 81 so as to be able to reciprocate. The fuel pipe part 82 is formed at the end of the cylinder part 81 and is opened with the fuel inflow pipe 82a to which fuel is supplied, the fuel outflow pipe 82b from which the fuel is discharged, and the inside of the cylinder part 81 facing toward each other. And an open end 82c of the fuel outflow pipe 82b.

  The valve 73 includes an armature portion 83 made of a substantially cylindrical magnetic body and a seal portion 84. The seal portion 84 is made of, for example, a metal having a cylindrical shape, and is integrated with the armature portion 83 by press-fitting, and can reciprocate integrally with the armature portion 83.

  The first spring 76 and the second spring 78 are arranged in series inside the bobbin 71 via a washer 79, and return the valve 73 from the suction position to the return position. Specifically, the first spring 76 and the second spring 78 move the armature portion 83 in the direction in which the valve 73 closes the communication between the fuel inflow tube 82a and the fuel outflow tube 82b, that is, in the direction in which the seal portion 84 is closed. Energized to move.

  As shown in FIG. 4A, the first spring 76 is formed of a single coil spring having a cylindrical shape and an unequal pitch. The first spring 76 has a portion 76a having a uniform winding length and a large winding pitch, and a small portion 76b. That is, the portion 76a having the winding pitch P1 has a large spring constant, and the portion 76b having the winding pitch P2 has a small spring constant. In the present embodiment, the first spring 76 is not limited to the above-described one, and may be a spring having nonlinear characteristics by changing the winding pitch, or may be a combination spring.

  As shown in FIG. 4B, the second spring 78 is formed of a single coil spring that is cylindrical and equidistantly spaced. The first spring 76 has a uniform winding length, and the winding length is set larger than that of the first spring 76. Moreover, a steel wire having a larger spring wire diameter than the first spring 76 is used for the second spring 78.

  As shown in FIG. 5, the first spring 76 has two polygonal spring characteristics with an inflection point 97 as a boundary, as indicated by a spring characteristic 95. Assuming that the state in which the valve 73 is in the valve closing position is zero, the first spring 76 has a displacement amount of the valve 73 corresponding to a load change in the first section A from the position to the stroke S1 from the stroke S1 to the stroke S2. The displacement amount of the valve 73 with respect to the load change in the second section B is larger.

  On the other hand, the second spring 78 has a linear spring characteristic as indicated by a spring characteristic 96. In the second spring 78, the displacement amount of the valve 73 with respect to the load change is larger than the displacement amount of the valve 73 with respect to the load change in the second section B of the first spring 76. The second spring 78 has an initial set load so that the stroke of the valve 73 is started with a load corresponding to the point 98. For this reason, it expands and contracts in the third section C from the stroke S2 to the stroke S3. When the valve load corresponding to the point 99 is applied, the second spring 78 becomes a top dead center (stroke end) to be described later in the stroke S3 of the valve 73.

  Further, the first spring 76 and the second spring 78 have a larger displacement in the first displacement section A and the third displacement section C than the conventional one in the first displacement section A and the third displacement section C (in the third displacement section C). Therefore, the moving speed of the valve 73 can be improved. Therefore, not only when the valve 73 is moved from the valve closing position to the valve opening position by the electromagnetic coil 72, but also when the valve 73 is moved from the valve opening position to the valve closing position, the moving speed of the valve 73 can be improved. . Specifically, in particular, in the third displacement section C, the displacement amount with respect to the load drop is large, and the time until the valve 73 moves to the valve closing position can be shortened.

  As shown in FIG. 2, the first spring 76 has the second spring 78 and the washer 79 so that the portion 76 a with the winding pitch P1 is on the valve 73 side and the portion 76 b with the winding pitch P2 is on the stator core 77 side. The bobbin 71 is housed in a predetermined assembly load. The assembly load of the first spring 76 corresponds to the initial setting load of the first spring 76 described above. This initial setting load is obtained by the pressure control device 32 in a state where the operation pressure fuel is sealed in the operation pressure fuel introduction passage 65. The load is such that the valve 73 can be held in the closed position so as to maintain the low pressure state.

  The bobbin 71 has a stopper member 80a that protrudes radially inward in the circumferential direction. The stopper member 80a regulates the extension of the second spring 78 in the direction of the valve 73 via the washer 79. It is supposed to be. The assembly load of the second spring 78 corresponds to the initial set load of the second spring, and is set to start bending from this initial set load. The stopper member 80a in the present embodiment corresponds to the flange in the present invention.

  Further, since the second spring 78 is housed inside the bobbin 71 together with the stator core 77, the side surface portion 80b of the bobbin portion 80 and the side surface portion 75a of the shield 75 can be removed. Further, after the first spring 76, the second spring 78, and the stator core 77 are inserted, the side surface portion 80b and the side surface portion 75a are press-fitted and positioned by these.

  As described above, the first spring 76 and the second spring 78 can be combined with a simple configuration, and the initial loads of the first spring 76 and the second spring 78 can be set.

  Further, the seal portion 84 can come into contact with the opening end portion 82c, and the opening end portion 82c is closed by being pressed by the first spring 76 and the second spring 78 through the armature portion 83. The communication between the fuel inflow pipe 82a and the fuel outflow pipe 82b is blocked.

  As shown in FIGS. 6A to 6D, the magnetic coil 72 moves the armature portion 83 in the direction to open the seal portion 84 because the magnetic flux passes through the armature portion 83 with high density when energized. It is possible to make it. The shield 75 is made of metal and is provided so as to cover the periphery of the electromagnetic coil 72. The shield 75 shields magnetic flux leaking from the electromagnetic coil 72 to the outside.

  As shown in FIG. 6A, when no voltage is applied to the electromagnetic coil 72, the valve 73 is pressed against the open end 82 c by the first spring 76 and the second spring 78. As a result, the communication between the fuel inflow pipe 82a and the fuel outflow pipe 82b is blocked. That is, the fuel switching valve 70 is a normally-off type. In addition, the state where the valve 73 is in the closed position as described above is defined as a bottom dead center.

  Next, as shown in FIG. 6B, when application of voltage to the electromagnetic coil 72 is started, the valve 73 is attracted by the electromagnetic coil 72 and separated from the opening end portion 82c, and a portion 76b of the winding pitch P2 is obtained. Will bend. As a result, the fuel inflow pipe 82a and the fuel outflow pipe 82b communicate with each other.

  Next, as shown in FIG. 6C, the valve 73 is attracted by the electromagnetic coil 72 and further separated from the opening end portion 82c, and the portion 76a of the winding pitch P1 of the first spring 76 is bent. Then, as shown in FIG. 6D, the valve 73 is attracted by the electromagnetic coil 72 and further separated from the opening end portion 82c, and the second spring 78 is bent. A state in which the valve 73 is most sucked, that is, a state in which the valve 73 is in the valve open position is defined as a top dead center.

  Thereby, the fuel switching valve 70 closes the operation pressure fuel in the operation pressure fuel introduction passage 65 by closing the valve and opens the operation pressure fuel from the operation pressure fuel introduction passage 65 by opening the valve.

  In the present embodiment, the position of the valve 73 corresponding to the bottom dead center, that is, the valve closing position means the return position, while the position of the valve 73 corresponding to the top dead center, that is, the valve opening position is the suction position. Means position. Therefore, the position corresponding to the valve opening position may be the return position, and the position corresponding to the valve closing position may be the suction position. Moreover, the fuel switching valve 70 is a normally-off type, but is not limited to this, and may be a normally-on type.

  As shown in FIG. 1, the ECU 4 includes a CPU (Central Processing Unit), a ROM (Read Only Memory) that stores fixed data, a RAM (Random Access Memory) that temporarily stores data, and a write A replaceable nonvolatile backup memory, an input interface circuit having an A / D converter and a buffer, and an output interface circuit having a drive circuit and the like are provided. The ECU 4 receives an ON / OFF signal of an ignition switch of the vehicle and is supplied with power from a battery (not shown).

  Furthermore, various sensor groups are connected to the input interface circuit of the ECU 4, and sensor information from these sensor groups is taken into the ECU 4 through an input interface circuit including an A / D converter and the like. The output interface circuit of the ECU 4 includes a relay switch for controlling actuators such as the injector 22, the fuel pump unit 40, and the fuel switching valve 70, a switching element for variably controlling the drive current of the fuel pump unit 40, and the like. It is connected.

  The ECU 4 can execute known electronic throttle control, fuel injection amount control, ignition timing control, fuel cut control, variable valve timing control, and the like by executing a control program stored in the ROM. For example, the ECU 4 calculates the basic injection amount required for each combustion based on the intake air amount detected by the air flow meter and the engine speed detected by the crank angle sensor, and further according to the operating state of the engine 2. The fuel injection amount subjected to various corrections and air-fuel ratio feedback correction is calculated, and the injector 22 corresponding to the fuel injection time corresponding to the fuel injection amount is driven to open. The fuel injection time here is set so as to maintain the stoichiometric air-fuel ratio in accordance with the set value of the fuel pressure supplied to the injector 22.

  Further, the ECU 4 generates a command value for the drive voltage of the pump drive motor 40b corresponding to the discharge amount so as to optimize the discharge amount of the fuel pump unit 40 in accordance with the fuel injection amount required for the operation of the engine 2. In addition, the fuel pump controller 45 has a function of feedback controlling the drive voltage of the pump drive motor 40b.

  Further, the ECU 4 repeatedly determines the load state during operation of the engine 2 based on sensor information from various sensor groups and set values and map information stored in advance in the ROM. For example, when the engine 2 is warmed up or at high fuel temperature, the electromagnetic coil 72 of the fuel switching valve 70 is energized so that the fuel pressure of the fuel from the fuel pump unit 40 is switched to the set pressure on the high pressure side. (See FIG. 7). In addition, for example, during normal operation after the engine 2 is warmed up or not at a high fuel temperature, the energization of the electromagnetic coil 72 of the fuel switching valve 70 is stopped to reduce the fuel pressure of the fuel from the fuel pump unit 40 to the low pressure side. The set pressure is switched to (see FIG. 7).

  The set values stored in the ROM and the backup memory of the ECU 4 include a set value on the high pressure side and a set value on the low pressure side of the fuel pressure, respectively. The map information stored in the ROM and the backup memory includes a map for determining the operating load and switching control of the fuel pressure according to the determination result.

  Next, the operation will be described.

  In the fuel supply device 3 of the present embodiment configured as described above, energization of the pump drive motor 40b of the fuel pump unit 40 and the electromagnetic coil 72 of the fuel switching valve 70 is stopped while the engine 2 is stopped. Is in a state of being. In the fuel switching valve 70, as shown in FIG. 6A, the valve 73 is pressed against the opening end portion 82c by the first spring 76 and the second spring 78, and the communication between the fuel inflow pipe 82a and the fuel outflow pipe 82b is established. Is blocked.

  When the engine 2 is started, the ECU 4 operates the injector 22 and the fuel pump unit 40. As shown in FIG. 1, the fuel discharged from the fuel pump unit 40 flows into the fuel pipe 44 through the check valve 43 and the fuel filter 42. The fuel from the fuel pipe 44 also flows into the branch pipe 44 a and enters the fuel pressure control valve 50.

  As shown in FIG. 7, when the engine 2 is started, the ECU 4 switches the fuel pressure of the fuel from the fuel pump unit 40 to a set pressure on the high pressure side. For this reason, as shown in FIG. 8A, the ECU 4 starts applying a voltage to the electromagnetic coil 72 of the fuel switching valve 70. As shown in FIG. 8B, the current rises gently by the application of voltage.

  When the current value exceeds the predetermined value 91, the attractive force acting on the valve 73 from the electromagnetic coil 72 exceeds the drag force of the first spring 76, and the valve 73 is shown in FIG. 8C by a solid line. Start moving from bottom dead center. At this time, the portion 76a of the winding pitch P1 of the first spring 76 is bent. Thereby, as shown in FIG. 6B, the valve 73 is separated from the opening end portion 82c, and the fuel inflow pipe 82a and the fuel outflow pipe 82b communicate with each other. As shown in FIG. 6C, the attractive force acting on the valve 73 from the electromagnetic coil 72 further exceeds the drag of the first spring 76, and the valve 73 moves toward the top dead center. At this time, the portion 76b of the winding pitch P2 of the first spring 76 is bent. Further, as shown in FIG. 6 (d), the top dead center is reached when the valve 73 moves most. Therefore, the fuel switching valve 70 is opened.

  As a result, at the initial stage of valve opening in the first displacement section A where the attractive force acting on the valve 73 from the electromagnetic coil 72 is small, the portion 76a of the winding pitch P1 of the first spring 76 having a large displacement with respect to the load variation is bent. I can do it. On the other hand, in the second displacement section B, since the attractive force acting on the valve 73 from the electromagnetic coil 72 is sufficiently higher than the initial stage of the first displacement section A, the displacement amount with respect to the load change amount is the winding pitch P1 of the first spring 76. The portion 76b of the winding pitch P2 of the first spring 76 smaller than the portion 76a can be sufficiently bent. As a result, as shown by a two-dot chain line in FIG. 8 (c), in the conventional fuel switching valve, the rising of the straight line of the graph becomes slow, whereas as shown by a solid line in FIG. In the form of the valve 73, the rising of the straight line in the graph has a steep slope. For this reason, since the moving speed of the valve 73 can be increased, the moving time from the bottom dead center to the top dead center can be shortened. As shown in FIGS. 6A to 6D, when the valve 73 moves from the bottom dead center to the top dead center, the fuel on the first spring 76 side of the valve 73 is used as the armature portion 83. To the fuel pipe 82 side of the valve 73.

  In this way, as shown in FIG. 8C, the movement time S1 from the bottom dead center to the top dead center by the valve 73 of the present embodiment is determined by the conventional fuel switching valve having a spring having linear characteristics. The moving time S2 from the bottom dead center to the top dead center can be significantly shortened. Thereby, the switching time from closing to opening of the fuel switching valve 70 can be shortened.

  Further, as shown in FIGS. 8A to 8D, the fuel switching valve 70 of the present embodiment has improved responsiveness of the valve 73 as compared with the conventional one, and therefore, from the application of voltage. The time T1 until the fuel pressure has actually finished rising is significantly shorter than the time T2 for the conventional fuel switching valve having a spring having linear characteristics. Further, in the fuel switching valve 70 of the present embodiment, as shown by a two-dot chain line in FIG. 8 (d), the conventional fuel switching valve has a slow rise in the straight line of the graph, whereas FIG. 8 (d). As shown by the solid line, the straight line rise of the graph has a steep slope in the valve 73 of the present embodiment. As a result, the speed of switching from the low pressure to the high pressure is faster than the conventional one.

  As described above, the fuel switching valve 70 of the present embodiment has improved response of the valve 73 as compared with the conventional one, so that even if a response delay of electromagnetic force occurs, the influence is small. Further, since the fuel switching valve 70 of this embodiment has improved responsiveness of the valve 73 compared to the conventional one, the initial set load of the first spring 76 shown in FIG. Even if it is set higher than the conventional one in consideration of the above, the time T1 can be shortened compared to the time T2, and the switching speed from the low pressure to the high pressure can be increased.

  Then, the fuel supplied from the fuel pump unit 40 to the fuel pressure control valve 50 enters the pressure regulating chamber 58 through the fluid inlet 51a as shown in FIG. Here, since the fuel switching valve 70 is in an open state, the operation pressure fuel introduction passage 65 is opened in the fuel tank 30. For this reason, as shown in FIG. 3B, the pressure receiving region of the pressure adjusting member 52 is only the annular pressure receiving surface 52 a of the pressure adjusting member 52.

  Accordingly, a large fuel pressure is required to open the pressure regulating member 52 against the urging force of the coil spring 53, and the pressure regulation level of the fuel in the annular introduction side passage 66 is increased. The fuel pressure in the branch pipe 44 a and the fuel pipe 44 also rises and quickly reaches a set pressure on the high pressure side, for example, 400 kPa, and high fuel pressure fuel is supplied to the delivery pipe 23 through the fuel passage 15. Thereby, by performing fuel injection from the injector 22 at a high pressure during warm-up, atomization of the spray can be achieved, and generation of unburned hydrocarbons during warm-up can be suppressed.

  As shown in FIGS. 8C and 8D, the fuel pressure starts to increase at the same time as the valve 73 of the fuel switching valve 70 starts to move even a little. And as shown to Fig.8 (a), ECU4 maintains the application of a voltage with respect to the electromagnetic coil 72 of the fuel switching valve 70 during warm-up operation. Thereby, as shown in FIG.8 (d), high pressure fuel injection is maintained.

  Next, as shown in FIG. 7, when the warm-up operation ends, the ECU 4 switches the fuel pressure of the fuel from the fuel pump unit 40 to a set pressure on the low pressure side.

  Therefore, as shown in FIG. 8A, the ECU 4 stops applying voltage to the electromagnetic coil 72 of the fuel switching valve 70. As shown in FIG. 8B, the current gradually drops due to the stop of the voltage application.

  When the current value falls below the predetermined value 92, the attractive force acting on the valve 73 from the electromagnetic coil 72 becomes smaller than the urging force of the second spring 78, and as shown in FIG. The spring 78 starts to move from the top dead center by the urging force of the spring 78. Thereby, as shown in FIG.6 (c), the valve | bulb 73 begins to approach the opening edge part 82c.

  Then, the attractive force acting on the valve 73 from the electromagnetic coil 72 becomes smaller than the biasing force of the first spring 76, and the valve 73 is bottom dead centered by the biasing force of the first spring 76, as shown in FIG. Move further toward. At this time, as shown in FIG. 6C, the portion 76b of the winding pitch P2 of the first spring 76 is extended.

  Further, the attractive force acting on the valve 73 from the electromagnetic coil 72 becomes smaller than the urging force of the first spring 76, and the valve 73 is opened by the urging force of the first spring 76 as shown in FIG. Move further towards 82c. At this time, as shown in FIG. 6B, the portion 76a of the winding pitch P1 of the first spring 76 is extended. As a result, as shown in FIG. 6A, the valve 73 comes into contact with and presses against the opening end portion 82c to reach the bottom dead center. Therefore, the fuel switching valve 70 is closed.

  As a result, at the initial stage of closing the valve where the attractive force acting on the valve 73 from the electromagnetic coil 72 is large, the second spring 78 is larger than the portion 76b of the winding pitch P2 of the first spring 76 by the second spring 78. 73 can move in the direction of the valve closing position in a short time. As a result, as shown by a two-dot chain line in FIG. 8 (c), the falling of the straight line of the graph is slow in the conventional fuel switching valve, whereas as shown by the solid line in FIG. In the form of the valve 73, the falling of the straight line in the graph has a steep slope. For this reason, since the moving speed of the valve 73 can be increased, the moving time from the top dead center to the bottom dead center can be shortened. As shown in FIGS. 6D to 6A, when the valve 73 moves from the top dead center to the bottom dead center, the fuel on the opening end portion 82c side of the valve 73 is supplied to the armature portion 83. From the valve 73 to the first spring 76 side.

  Thus, as shown in FIG. 8C, the travel time S3 from the top dead center to the bottom dead center by the valve 73 according to the present embodiment is determined by the conventional fuel switching valve having a spring having a linear characteristic. The moving time from the top dead center to the bottom dead center S4 can be made significantly shorter. Thereby, the switching time from opening to closing of the fuel switching valve 70 can be shortened.

  The fuel supplied from the fuel pump unit 40 to the fuel pressure control valve 50 enters the pressure regulating chamber 58 from the fluid inlet 51a as shown in FIG. Here, after the fuel switching valve 70 is closed, the operating pressure fuel introduction passage 65 is closed. For this reason, as shown in FIG. 2B, the pressure receiving regions of the pressure adjusting member 52 are the annular pressure receiving surface 52a and the annular pressure receiving surface 52b of the pressure adjusting member 52.

  Accordingly, a small fuel pressure is sufficient to open the pressure regulating member 52 against the urging force of the coil spring 53, and the pressure regulation level of the fuel in the annular introduction side passage 66 is lowered. Then, as shown in FIGS. 8C and 8D, the fuel pressure starts to drop at the same time as the valve 73 of the fuel switching valve 70 is completely closed. Therefore, the fuel pressure in the branch pipe 44a and the fuel pipe 44 also decreases, and quickly reaches a set pressure on the low pressure side, for example, 200 kPa, and the low fuel pressure fuel is supplied to the delivery pipe 23 through the fuel passage 15. Thereby, the fuel consumption can be improved by operating the pump unit 40 at a low pressure.

  Further, as shown in FIGS. 8A to 8D, a time T3 from when the voltage application is stopped according to the present embodiment to when the fuel pressure actually starts to decrease is a spring having a conventional linear characteristic. Compared with the time T4 by the fuel switching valve provided with

  In addition, after a certain time has elapsed since the engine 2 was started, a set pressure on the low pressure side is required in terms of fuel efficiency and the reliability of the fuel pump unit 40 in a normal operation state, for example, partial load operation. On the other hand, at a high fuel temperature, a set pressure on the high pressure side is required to suppress the generation of vapor.

  As described above, according to the fuel supply device 3 according to the present embodiment, when the valve 73 is moved from the return position to the suction position by the electromagnetic coil, the valve body is at least in the first displacement section A as compared with the prior art. Since the displacement amount of the valve body with respect to the change amount of the load acting on the valve increases, the moving speed of the valve 73 can be improved.

  In addition, by improving the responsiveness of the valve 73, the time lag from when the voltage is applied to the electromagnetic coil until the fuel supply pressure to the fuel consuming part is actually changed is shortened, and the error of the time lag is reduced. The time lag calculation accuracy can be improved.

  In addition, by improving the responsiveness of the valve 73, the speed at which the fuel pressure of the fuel to be controlled is switched from, for example, a low pressure to a high pressure is increased. For this reason, the pump pressure can be rapidly increased from the low pressure to the high pressure, so that fuel efficiency can be improved.

  Further, according to the fuel supply device 3 according to the present embodiment, when the valve 73 moves from the valve opening position to the valve closing position, the change in the load acting on the valve body in the third displacement section C compared to the conventional case is changed. Since the displacement amount of the valve body with respect to the amount increases, the moving speed of the valve 73 can be improved. Moreover, when the valve 73 moves from the valve opening position to the valve closing position, the amount of displacement with respect to the load drop is large, and the time until the valve 73 moves to the valve closing position can be shortened.

  Thus, by improving the responsiveness of the valve 73, the time lag from when the voltage is no longer applied to the electromagnetic coil 72 until the fuel supply pressure to the injector 22 is actually changed is shortened, and the error of the time lag The accuracy of time lag calculation can be improved.

  Further, by improving the responsiveness of the valve 73, the speed at which the fuel pressure of the fuel to be controlled is switched from high pressure to low pressure, for example, is increased. For this reason, since the pump pressure can be quickly reduced from a high pressure to a low pressure, fuel consumption can be improved.

  Further, by moving the valve 73 from one of the valve closing position and the valve opening position to the other, the fuel switching valve 70 introduces the operating pressure fuel into the operating pressure fuel introduction passage 65 of the fuel pressure control valve 50. It is possible to switch whether or not. Since the area of the pressure receiving region of the pressure regulating member 52 can be easily changed depending on whether or not the operating pressure fuel is introduced into the operating pressure fuel introduction passage 65, the pressure of the fuel to be controlled by the fuel pressure control valve 50 can be easily set. Can be controlled.

  Further, according to the fuel supply device 3 according to the present embodiment, the fluid introduction port 51 a, the fluid discharge port 51 b, and the operation pressure introduction hole 51 c of the fuel pressure control valve 50 regulate the pressure with respect to the pressure regulating member 52. Arranged on the chamber 58 side. For this reason, it is not necessary to introduce the operation pressure fuel into the back pressure chamber 59, and the fuel and operation pressure fuel pipes may be provided only on the pressure adjustment chamber 58 side of the fuel pressure control valve 50. For this reason, the fuel pressure control valve 50 capable of a compact and simple piping can be provided. Further, according to the fuel supply device 3 according to the present embodiment, the fuel pressure can be adjusted in two stages without making the inside of the housing 51 into three chambers or providing two fuel pressure control valves.

  In the fuel supply device 3 of the present embodiment described above, the fuel pressure control valve 50 is configured such that the operation pressure introduction hole 51c is disposed on the pressure regulating chamber 58 side. However, the fuel supply device according to the present invention is not limited to this, and the fuel pressure control valve 50 may have the operation pressure introduction hole 51c arranged on the back pressure chamber 59 side.

(Second Embodiment)
The present embodiment has an overall configuration substantially similar to that of the first embodiment described above. In the fuel supply device according to the present embodiment, the configuration of the first spring of the fuel switching valve 70 is different, but the other configurations are configured similarly. Therefore, the same configuration will be described using the same reference numerals as those of the first embodiment shown in FIGS. 1 to 7, and only differences will be described in detail.

  As shown in FIG. 9, the first spring 74 is formed of a single coil spring having a cylindrical shape and an equal pitch. For this reason, the first spring 74 has a uniform winding length like the first spring 76 described above, but has the same winding pitch unlike the first spring 76. On the other hand, the second spring 78 is the same as that in the first embodiment, and constitutes a combination spring with the first spring 74.

  As shown in FIG. 10, the first spring 74 has a linear spring characteristic with a low spring constant as compared with a conventional spring, as indicated by a spring characteristic 93. Assuming that the state in which the valve 73 is in the valve closing position is zero, the first spring 76 has a displacement amount of the valve 73 with respect to a load change in the first section A from the position to the stroke S1 in comparison with the conventional spring characteristics. It ’s getting bigger.

  On the other hand, the second spring 78 has a linear spring characteristic as indicated by a spring characteristic 96. In the second spring 78, the displacement amount of the valve 73 with respect to the load change in the second section B from the stroke S1 to the stroke S2 is larger than the conventional spring characteristics.

  The second spring 78 has an initial set load so that the stroke of the valve 73 is started with a load corresponding to the point 98. For this reason, it expands and contracts in the second section B from the stroke S1 to the stroke S2. When the valve load corresponding to the point 99 is applied, the second spring 78 becomes a top dead center which will be described later in the stroke S3 of the valve 73.

  Further, as shown in FIG. 10, the valve 73 is not displaced from the load corresponding to the point 94 to the load corresponding to the point 98, but the operation in the operation pressure introduction passage 65 enclosed in the stroke S1 is performed. The pressurized fuel can be discharged sufficiently.

  The first spring 74 is housed in the bobbin 71 with a predetermined assembly load together with the second spring 78 and the washer 79. The assembly load of the first spring 74 corresponds to the initial setting load of the first spring 74 and is larger than the load that holds the valve 73 in the closed position in a state where the operation pressure fuel is sealed in the operation pressure fuel introduction passage 65. Is set to

  The second spring 78 is thicker in spring steel wire and larger in winding length than the first spring 74. Further, the bobbin 71 has a stopper member 80a projecting radially inward in the circumferential direction thereof, and restricts the extension of the second spring 78 in the direction of the valve 73 via the washer 79. ing. The assembly load of the second spring 78 corresponds to the initial setting load of the second spring 78, and the bending is started from this initial setting load.

  As described above, according to the fuel supply device 3 according to the present embodiment, when the valve 73 is moved from the return position to the suction position by the electromagnetic coil, at least in the first displacement section A as compared with the conventional load. Since the amount of displacement with respect to the amount of change increases, the moving speed of the valve 73 can be improved.

  In addition, by improving the responsiveness of the valve 73, the time lag from when the voltage is applied to the electromagnetic coil until the fuel supply pressure to the fuel consuming part is actually changed is shortened, and the error of the time lag is reduced. The time lag calculation accuracy can be improved.

  In addition, by improving the responsiveness of the valve 73, the speed at which the fuel pressure of the fuel to be controlled is switched from, for example, a low pressure to a high pressure is increased. For this reason, the pump pressure can be rapidly increased from the low pressure to the high pressure, so that fuel efficiency can be improved.

  Further, according to the fuel supply device 3 according to the present embodiment, when the valve 73 is moved from the valve opening position to the valve closing position by the electromagnetic coil 72, the load change in the second displacement section B compared to the conventional case. Since the displacement amount of the valve body with respect to the amount increases, the moving speed of the valve 73 can be improved. Moreover, even when the valve 73 is moved from the valve opening position to the valve closing position by the electromagnetic coil 72, the displacement amount with respect to the load removal is large, and the time until the valve 73 moves to the valve closing position can be shortened.

  Thus, by improving the responsiveness of the valve 73, the time lag from when the voltage is no longer applied to the electromagnetic coil 72 until the fuel supply pressure to the injector 22 is actually changed is shortened, and the error of the time lag The accuracy of time lag calculation can be improved.

  Further, by improving the responsiveness of the valve 73, the speed at which the fuel pressure of the fuel to be controlled is switched from high pressure to low pressure, for example, is increased. For this reason, since the pump pressure can be quickly reduced from a high pressure to a low pressure, fuel consumption can be improved.

  As described above, the pressure control device according to the present invention and the fuel supply device including the pressure control device can improve the responsiveness when the fuel pressure is changed as compared with the conventional case, and calculate the fuel supply pressure switching time. This has the effect of improving the accuracy and further improving the fuel efficiency, and is useful for the pressure control device and the fuel supply device including the pressure control device.

2 Engine (Internal combustion engine)
3 Fuel supply device 22 Injector (fuel consumption unit)
32 Pressure control device 50 Fuel pressure control valve 52 Pressure regulating member 65 Operation pressure fuel introduction passage 70 Fuel switching valve 71 Bobbin 72 Electromagnetic coil 73 Valve (valve element)
76 First spring (biasing means)
78 Second spring (another biasing means)
79 Washer 80 Bobbin portion 80a Stopper member (flange)
80b Side part 81 Cylinder part 82 Fuel pipe part (fuel distribution part)
83 Armature part 84 Seal part

Claims (5)

A fuel pressure control valve for controlling the pressure of the fuel to be controlled by switching the pressure of the operating pressure fuel, and a fuel switching valve for switching the pressure of the operating pressure fuel,
The fuel switching valve includes a bobbin that forms a fuel circulation part through which the operating pressure fuel flows;
A valve body accommodated in the bobbin so as to be capable of reciprocating and capable of opening and closing the fuel circulation part by reciprocating;
An electromagnetic coil wound around the bobbin and sucking the valve body to a suction position;
An urging means housed in the bobbin and returning the valve body from a suction position to a return position,
The fuel pressure control valve includes a housing having a fluid introduction port through which the control target fuel is introduced, a fluid discharge port through which the control target fuel is discharged, and an operation pressure fuel introduction passage through which the operation pressure fuel is introduced, and the housing A partition wall that communicates with the fluid inlet and forms a pressure regulating chamber having the operation pressure fuel introduction passage and communicates the fluid inlet and the fluid outlet according to the fuel pressure in the pressure regulating chamber. And a pressure regulating member,
In the fuel pressure control valve, when the operating pressure fuel is introduced into the operating pressure fuel introduction passage, the area of the pressure receiving region where the pressure adjusting member receives fuel pressure on one side is changed, and the area of the pressure receiving region is increased. The fuel pressure in the pressure regulating chamber is adjusted accordingly,
The fuel switching valve seals the operation pressure fuel into the operation pressure fuel introduction passage when the valve body is in the return position, and the valve body moves from the return position to the suction position so that the operation pressure fuel introduction passage Configured to release operating pressure fuel,
The urging means has a displacement amount of the valve body with respect to a change amount of a load acting on the valve body in a first displacement section from the return position to a predetermined displacement position after the first displacement section. A pressure control device having a non-linear characteristic larger than a displacement amount of the valve body with respect to a change amount of a load acting on the valve body in two displacement sections. It is arranged in series with respect to the urging means, further comprising another urging means for returning the valve body from the suction position to the return position,
The other urging means is configured such that a displacement amount of the valve body with respect to a change amount of a load acting on the valve body in a third displacement section after the second displacement section is applied to the valve body in the second displacement section. The pressure control device according to claim 1, wherein the pressure control device is larger than a displacement amount of the valve body with respect to a change amount of an applied load.   A flange projecting radially inwardly of the bobbin, a washer provided between the flange and the other biasing means, and positioning the other biasing means on a side facing the flange. The pressure control device according to claim 2, further comprising: a side surface portion that constitutes a bobbin, wherein the another urging means is accommodated inside the bobbin so as to have a predetermined initial load. . A pressure control device according to any one of claims 1 to 3 is provided,
A fuel supply device, wherein the pressure of the control target fuel supplied to a fuel consumption unit is regulated by the pressure control device. The fuel supply device according to claim 4, wherein the fuel consumption unit is a fuel injection unit of an internal combustion engine.

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