JP5756488B2 - Valve device - Google Patents

Description

  The present invention relates to a valve device. In particular, the present invention relates to a valve device for a fuel injection device.

  The present invention relates to a valve device used to deliver fuel to a cylinder of a diesel internal combustion engine of the following type, where the fuel is supplied to a high pressure accumulator ("common rail") by a suitable pump: Further, the fuel is delivered from the accumulator to the fuel injection device of the engine. The nozzle of the fuel injection device is configured to operate so as to deliver fuel to each cylinder of the engine.

  Such a fuel injection device generally includes a needle that is slidable within the main body and engageable with a valve seat so as to control the flow of fuel passing through the main body from a high-pressure fuel supply path. Yes.

  The maximum injection pressure within the fuel injector may be of the order of 1800 bar or higher, resulting in a high force that must be exceeded to lift the injector needle. Therefore, the injection device cannot be directly controlled using the electromagnetic actuator except when a very large current is passed. Therefore, the injection device is indirectly controlled by a valve device that controls pressurization or discharge of a control chamber disposed on the valve needle.

  An example of such an injection device is disclosed in EP 0 647 780, where the end of a needle remote from the valve seat extends into the chamber, which is fed through a flow restrictor. It is configured to receive fuel from the road. In use, injection is controlled by changing the pressure in the control chamber. The solenoid actuator acts on the valve device to open a flow path between the control chamber and the low-pressure discharge part. As the pressure decreases in the control chamber, the needle moves away from the valve seat due to the pressure acting on the portion of the needle adjacent to the valve seat.

In a common rail injection system, two types of valve devices are known: pressure balanced valve devices (sometimes referred to as balanced valves) and non-pressure balanced valve devices.
In the pressure balanced type valve device, the valve rod arranged in the hole is slidable under the operation of the electromagnetic actuator, and a flow path between the high pressure region of the control chamber and the low pressure region of the low pressure discharge part is provided. Open and close. In the closed state, the valve device is in contact with the valve seat and is in a substantially balanced state of fluid pressure, and is held in the closed position by the spring acting on the valve device. When the electromagnetic actuator is actuated, the spring force is overcome, the valve device leaves the valve seat, and fuel flows from between the valve stem and the hole to the low pressure discharge. Equilibrium based valve devices tend to generate some static leakage. In other words, even in the closed position, high pressure fuel will leak into the low pressure discharge along the flow path defined between the valve device bore and the valve stem.

  In non-pressure balanced valve devices, the valve is held in a seated and closed position by the pressure of the high pressure fuel in the system. Therefore, such a valve device is not substantially in a state of pressure equilibrium in the closed position, and as a result, requires a larger operating force to open. However, the degree of static leakage in such a non-pressure balanced valve device is lower than the degree of static leakage in the pressure balanced valve device.

  Therefore, the above two types of valve devices require only a small operating force but have a relatively high degree of static leakage (pressure balanced valve device), or require a large operating force but are static. The degree of leakage is relatively low (non-pressure balanced valve device).

European Patent No. 0647780 European Patent No. 0740068

  It is an object of the present invention to provide a valve device that requires a small actuation force but has improved static leakage performance.

  According to the first aspect of the present invention, an open state that forms a flow path for pressurized fuel from a control chamber of the injection apparatus to a low-pressure discharge part and a closed state that closes the flow path are used in the injection apparatus. A valve device configured to be movable between states is provided. The valve device is arranged in the injection device, and is configured to close a first end portion of the valve guide portion when the valve device is in a closed state, and a valve guide portion that forms at least a part of the flow path And a biasing member configured to bias the valve device toward the closed state, and the biasing member includes an elastic member disposed in the valve guide portion, and is provided in the valve guide portion. A volume is defined.

  The present invention provides a valve device in which a valve device (/ valve head) is biased toward a closed state by the action of an elastic member, and the elastic member is disposed in the valve guide portion, and the volume portion in the valve guide portion. Is defined. The elastic member is significantly different from known devices that use spring devices.

  By using the elastic member, it is possible to configure the valve device so that the pressure is substantially balanced in the closed state. Due to the valve head, the valve guide can be closed by the valve head in the closed state so that static leakage is minimized.

Therefore, according to the valve device of the present invention, it is possible to provide a valve with a relatively small degree of static leakage and a relatively small force required for operation.
The elastic member / biasing member partitions the valve guide portion with a partition wall and defines a volume within the valve guide portion (so that the first portion of the valve guide portion is not in fluid communication with the second portion of the valve guide portion). Please note that.

  Conveniently, the valve device may be configured to substantially balance the pressure when in the closed state. The force acting on the valve head by the fuel pressure in the valve guide may be configured to be substantially equal to the force acting on the biasing member by the fuel pressure in the valve guide. The force acting on the biasing member and the force acting on the biasing member act in substantially opposite directions.

Conveniently, the valve device comprises a valve stem configured to be disposed within the valve guide, the valve head is disposed at the first end of the valve stem, and the biasing member is the valve stem. Is disposed at the second end.
In one variation of the invention, the biasing member may comprise a substantially flat elastic plate member. In another variation of the present invention, the biasing member may comprise a plate-like member having a ridge. By providing the protrusions on the plate-like member, the responsiveness of the urging member can be conveniently changed.

  In yet another variant of the invention, the biasing member may be formed in a substantially flat elastic part and a bar part, the valve head being arranged at the first end of the bar part and elastic The part is arranged at the second end of the bar part. This variant has the advantage of being lighter than one with a hard bar and may be beneficial in performance (eg, a more responsive valve device). The rod portion may be substantially cylindrical and may include a plurality of grooves. The valve head may be attached to one end of the rod portion. Alternatively, the valve head may have an annular structure and the rod may protrude through the valve head. This alternative structure allows for a simpler manufacturing process.

  The valve guide may include a valve groove at a second end of the valve guide away from the first end, and the biasing member is disposed in the valve groove. The valve groove part may have a larger cross-sectional area than the main hole of the valve guide part. The biasing member forms a partition across the valve groove, whereby the valve head and valve stem / valve hole are located on one side of the partition and the volume is formed on the other side of the partition (partition Are not in fluid communication with each other). The volume may be filled with fuel or configured to be in fluid communication with a fuel return reverse leak circuit / fuel reverse leak return passage communicating with the reverse leak circuit.

  According to the second aspect of the present invention, there is provided an injection device used for delivering fuel to a cylinder of an internal combustion engine, and the injection device is slid within a hole of a nozzle body and a main body having a hole. Actuated by an actuator to allow a movable valve needle, an actuator, a fuel supply path to supply pressurized fuel to the control chamber, and allow fuel to flow from the control chamber to the low pressure discharge And the valve device according to the first aspect of the present invention.

  Preferred features of the second aspect of the invention may comprise preferred features of the first aspect of the invention.

It is a figure which shows a known pressure balance type valve apparatus. FIG. 2A is a diagram showing a fuel injection process in a typical injection device. FIG. 2B is a diagram showing a fuel injection process in a typical injection device. It is a figure which shows the valve apparatus (closed state) by embodiment of this invention. FIG. 4 shows the valve device of FIG. 3 in an open state. FIG. 6 illustrates an additional embodiment of the present invention. FIG. 6 illustrates an additional embodiment of the present invention. FIG. 6 illustrates an additional embodiment of the present invention. FIG. 6 illustrates an additional embodiment of the present invention. FIG. 6 illustrates an additional embodiment of the present invention.

FIG. 1 shows an example of a pressure balanced valve device described in European Patent No. 0740068.
The known fuel injection device shown in FIG. 1 includes a valve body 10 including a first region having a relatively small diameter and a second region having a large diameter. The valve body 10 is provided with a hole 11 extending through the first region and the second region, and the hole terminates at a position spaced from the free end of the first region. Within the bore, an elongated valve needle 12 is slidable, the valve needle 12 being configured to engage a valve seat defined by the inner surface of the valve body 10 adjacent the blind end of the bore. A tip region 14 formed. The valve body 10 is provided with one or more openings 15 that communicate with the holes. The openings are arranged such that engagement of the tip 14 with the valve seat prevents fluid from flowing out of the valve body 10 through the opening, and when the tip 14 is lifted from the valve seat, Fluid can be delivered.

  As shown in FIG. 1, the valve needle 12 has a portion that extends into the first region of the valve body 10 to allow fluid flow between the valve needle 12 and the inner surface of the valve body 10. In other words, the diameter is smaller than the diameter of the hole. Within the second region of the valve body 10, the valve needle 12 has a larger diameter, substantially preventing fluid from flowing between the valve needle 12 and the valve body 10.

  An annular passage 16 is provided in the second region of the valve body 10. The annular passage 16 is in communication with a fuel supply path 18 configured to receive high pressure fuel from the accumulator of the associated fuel delivery system. In order to allow fuel to flow from the passage 16 to the first region of the valve body 10, the valve needle 12 is provided with a grooved region 20. The grooved region 20 allows fuel to flow from the annular passage 16 to the first portion of the valve body 10 and the valve needle 12 moves laterally within the valve body 10. This prevents the movement in the axial direction from being restricted.

  In the second region of the valve body 10, a chamber 22 is provided at a position away from the first region, and the chamber 22 communicates with the high-pressure fuel path 18 through the flow restricting unit 24. . As shown in FIG. 1, the chamber 22 is provided at the end of the valve body 10 and is closed by a plate-like member 26.

  A projection 28 having a reduced diameter is provided at the end of the valve needle 12 away from the tip 14 of the valve needle 12. The protrusion 28 guides the compression spring 30 engaged between the valve needle 12 and the plate-like member 26, and biases the valve needle 12 to a position where the tip 14 engages with the valve seat.

  A main body 34 is engaged with the side of the plate-like member 26 opposite to the side engaged with the valve main body 10. Both the main body 34 and the plate-like member 26 define a chamber 35 that communicates with the chamber 22 through the opening 32. The body 34 is further provided with a hole spaced from the axis of the body 34, and a valve member 36 (“valve device”) is slidable inside the hole. The valve member 36 includes a cylindrical rod portion provided with a closed hole extending in the axial direction (in other words, a blind hole). The open end of the hole can communicate with the chamber 35 when the valve member 36 is lifted such that the end of the valve member 36 is separated from the plate member 26. The communication is interrupted when the valve member 36 is engaged with the plate member 26. The pair of radially extending passages 38 communicates with the closed hole in the vicinity of the closed end and communicates with a chamber connected to an appropriate low pressure discharge. ing.

  The main body 34, the plate-like member 26, and the valve main body 10 are attached to the nozzle holder 42 using a cap nut 40. The cap nut 40 engages with the end of the second region of the valve body 10 in the vicinity of the interconnected portion with the first region. The nozzle holder 42 includes a recess in which a solenoid actuator 44 is provided.

  As shown in FIG. 1, the solenoid actuator 44 includes a generally cylindrical core member 44a including an axially closed hole, and a winding wound on the core member 44a and connected to a suitable control device. A wire 44b and a cylindrical yoke 44c extending around the core member 44a and the winding 44b are provided. The face of the core member 44a and the face of the yoke 44c facing the valve member 36 define a pole face.

  The valve member 36 supports the armature 36a. When the solenoid actuator 44 is energized, the armature 36a and the valve member 36 are lifted so that the valve member 36 is disengaged from the plate member 26. When the solenoid actuator 44 is de-energized, the valve member 36 returns to its original position under the action of the spring 46 placed in the closed hole of the core member 44a.

  The movement restricting body 47 is also placed in the closed hole of the core member 44a, and the movement restricting body 47 has a spring to prevent the armature 36a from contacting the magnetic pole surface of the core member 44a and the magnetic pole surface of the yoke 44c. The movement of the valve member 36 against the action of 46 is limited. Note that the spring 46 provides a closing force against the valve and maintains the contact pressure on the valve seat when the valve is closed.

  As shown in the drawing, the supply path 18 includes a nozzle holder 42, a main body 34, a plate-like member 26, and holes provided in the valve main body 10. In order to ensure alignment of these holes, a pin 48 is provided, and the pin 48 is an appropriate one provided in each of the nozzle holder 42, the main body 34, the plate-like member 26, and the valve main body 10. It is put in the recess.

  In use, in the position shown in FIG. 1, the valve needle 12 is biased by the spring 30 so that the tip 14 engages with the valve seat, so that fuel is not delivered from the opening. At this position, since the pressure of the fuel in the chamber 22 is high, the force acting on the end of the valve needle 12 by the pressure of the fuel and the elastic force of the spring 30 causes the high pressure fuel acting on the inclined surface of the valve needle 12. This sufficiently exceeds the upward force acting on the valve needle 12.

  In order to lift the tip 14 of the valve needle 12 from the valve seat and deliver fuel from the opening, the solenoid actuator 44 is energized, and the end of the valve member 36 is separated from the plate-like member 26 against the action of the spring 46. The valve member 36 is lifted so as to be lifted away. When the valve member 36 is lifted in this way, the fuel flows from the chamber 35 and thus the chamber 22 through the hole and the passage 38 of the valve member 36 to the discharge portion. The flow of fuel from the chamber 22 reduces the pressure in the chamber 22 and the flow restricting section 24 is installed, so that the flow of fuel from the fuel supply path 18 to the chamber 22 is restricted. As the pressure in the chamber 22 decreases, the combination of the force applied to the valve member 12 by the pressure in the chamber 22 and the force applied to the valve member 12 by the spring 30 results in a valve seat at the tip 14 of the valve member 12. A state is reached where it is no longer sufficient to maintain the engagement, so that further reduction in pressure in the chamber 22 lifts the valve needle 12 and allows fuel to be delivered through the opening.

  In order to lower the initial injection rate, the solenoid actuator 44 may be configured to lift the valve member 36 slightly. Thereby, the flow of fuel from the chamber 22 to the discharge part is regulated. Similarly, the opening 32 may be of a regulated diameter so as to regulate the flow of fuel from the chamber 22.

  As the valve needle 12 is lifted, the protrusion 28 approaches the opening 32 and restricts the flow of fuel through the opening 32. It will be appreciated that this has the effect of decelerating the valve needle 12 toward the end of the travel of the valve needle 12.

  In order to finish the delivery, the solenoid actuator 44 is deenergized, and the valve member 36 is moved downward until the end of the valve member 36 is engaged with the plate member 26 under the action of the spring 46. It is done. By such an operation of the valve member 36, the communication with the discharge part of the chamber 35 is cut off, and therefore the pressure in the chamber 35 and the chamber 22 increases. The pressure applied to the valve needle 12 by the pressure in the chamber 22 and the spring 30 reaches a state exceeding the force for opening the valve. It will move to a position to engage and prevent further delivery of fuel.

  From the above description and FIG. 1, since the valve member 36 and the solenoid actuator 44 are not coaxial with the valve needle 12, the valve holder 42 and the body 34 are each relatively thick on the wall as compared to the conventional device. By placing a supply path 18 that includes a portion and extends within a relatively thick portion of the wall, the risk of breakdown of the injector by supplying high pressure fuel to the fuel supply path 18 is reduced. It is understood that

  2A and 2B show an injection process in a general known injection device 1. Similar elements between FIGS. 1 and 2 are indicated by similar reference numerals. The injection device of FIGS. 1 and 2 includes an electromagnetic actuator device 44 disposed above the valve device 50. A spacer component 52 is provided below the valve device 50 and above the needle 12. The spacer 52 contains the control chamber 22 and three adjusted orifices 54, 56, 58 that allow operation of the injector.

  The valve device 50 includes a valve stem portion 60 that supports the armature 62 at one end. The rod portion is slidable within the hole 64. The valve stem portion has several pressure reducing grooves, and the end portion of the rod portion on the armature side has a seal surface 66 that can be engaged with the seat portion 68 at the end of the hole. When the sealing surface is brought into contact with the seat, contact is made that forms a pressure seal. A valve spring 46 (not shown in FIGS. 2A and 2B) is disposed above the armature and acts to engage the sealing surface with the seat.

  Within the spacer component 52 are an injection supply orifice 58 (also referred to as a nozzle flow orifice or NPO), a control chamber discharge orifice 54 (also referred to as an outflow orifice or SPO), and a control chamber injection orifice 56 (inlet orifice). Or also called INO).

Here, operation | movement of an injection apparatus is demonstrated easily, referring FIG. 2A and 2B.
In FIG. 2A, the valve device 50 is closed and the sealing surface 66 is engaged with the seat 68. Therefore, the control chamber 22 is exposed to the pressure in the common rail. The high pressure fuel exerts a force on the upper surface of the needle 12 that exceeds the pressure of the fuel acting on the pressure surface 70 of the needle 12. Therefore, the needle is held in a closed state so that there is no injection through the orifice 15.

  In FIG. 2B, the actuator 44 is energized and lifts the armature 62 so that the valve device 50 is positioned in the open position where the seal surface 66 is lifted from the seat 68. At this time, the fuel contained in the control chamber 22 has a flow path connected to the low-pressure discharge section through the outflow adjustment orifice 54 (SPO), and therefore the fuel flows from the control chamber 22. Initially, the pressure acting on the upper surface of the needle 12 by the fuel in the control chamber 22 and the spring 30 of the injector exceeds the pressure generated on the pressure surface 70.

  However, as soon as the pressure acting on the pressure surface 70 by the fuel exceeds the spring force and the force generated by the fuel in the control chamber 22, the needle 12 is lifted and fuel injection through the orifice 15 begins, FIG. As shown, the fuel flows from the common rail through the nozzle channel orifice 58.

  To stop the injection, the electromagnetic actuator 44 is de-energized and the valve spring 46 (not shown in FIG. 2) closes the valve device 50. High pressure fuel passes from the supply path 18 through the control chamber injection orifice 56 (INO), and the pressure in the control chamber 22 rises until injection stops.

3 and 4 illustrate the operation of the valve device 100 according to an embodiment of the present invention. 3 and 4, like elements between FIGS. 1-4 are indicated by like reference numerals.
3 and 4 includes a valve stem portion 102 and a valve head portion 104 disposed at one end of the valve stem portion 102. The valve device 100 is generally disposed within the valve guide 106. The valve guide portion includes a hole 108, and the hole 108 opens at the first end portion 110 and opens into the valve groove portion 112 at the second end portion 111.

  FIG. 3 shows the valve device 100 in a closed state in which there is no fuel flow path from the control chamber 22 to the low-pressure discharge unit (not shown). As shown in FIG. 3, when the valve device 100 is in the closed state, the cross-sectional area of the valve head 104 changes so that the valve head 104 sits on the opening 110 of the valve guide 106 to form a seal. Please note that.

FIG. 4 shows the valve device in an open state with a fuel flow path 114 from the control chamber 22 through the outflow orifice 54 to the low pressure discharge.
Instead of the valve spring as shown in FIG. 1, the valve device of FIGS. 3 and 4 includes a biasing member 120 disposed at the end of the valve stem 102 away from the valve head 104. The urging member is configured to urge the valve device toward the closed state. The biasing member in FIGS. 3 and 4 includes a substantially flat elastic plate-like member disposed in the valve groove 112.

  In the closed state, the urging member 120 is configured such that the pressure acting on the valve head 104 by the fuel is substantially equal to the pressure acting on the elastic plate member 120. By this method, when the valve device 100 is in the closed state, the pressure is substantially balanced. Further, the valve is held in a closed state against a small pressure change by the elastic plate-like member that exerts a force downward (that is, in the direction of the needle from the actuator device in the configuration of FIG. 3).

  In FIG. 4, the actuator device 44 is energized. The upward force generated by the actuator device 44 exceeds the downward force from the elastic plate-like member 120. As a result, the valve device 100 is lifted upward to be in the open state. The valve head 104 is no longer seated in the orifice 110 of the valve hole 108, so that fuel can flow from the control chamber 22 and the needle 12 can be lifted from the seated position to the low pressure discharge. The fuel flow path 114 is open. It can be seen that the elastic plate member 120 is slightly deformed 122 due to the force generated by the actuator.

  When the actuator 44 is de-energized, the elastic plate member 120 returns to its previous substantially flat shape and consequently closes the flow path by returning the valve head to the valve seat 110. Then, as fuel flows through the INO 56 to the control chamber, the pressure in the control chamber 22 rises again as described above in connection with FIGS. 2A and 2B.

  The volume 124 under the biasing member 120 was connected to a fuel reverse leak (in other words, back leak) return passage (connection not shown in FIGS. 3-9) and filled with fuel. It should be noted that it is a volume part and allows the elastic plate-like member to be deformed as necessary.

  The elastic plate-like member may include a steel plate material. The steel plate material is configured to give the valve member 106 a sufficient closing force so that the spring 46 shown in FIG. 1 is not necessary. Note that when the spring 46 is removed from the injector, more space is available for the magnetic material in the actuator (eg, the core member 44a of FIG. 1 can be made larger). As the material in the core member of the actuator increases, the performance of the actuator is improved, thus improving the performance of the valve. It should also be noted that when the spring 46 is removed, the stop member 47 can be simplified, reducing the cost of the valve.

  Typically, the steel plate material is designed so as to give more force than the past design in the range of 25 to 50 N depending on the type of the injection device. By using a steel plate material (biasing member) instead of the winding spring, the functionality of the valve is improved. The valve response time is improved compared to a spring-based configuration, and the tolerance of the initial opening force by the actuator is smaller, reducing the variation in performance of different valves during manufacture.

  A further embodiment of the invention is shown in FIGS. In each of FIGS. 5-8, the valve device is shown in the closed state. Note that like reference numerals are used to indicate like elements in FIGS.

  In FIG. 5, the substantially flat elastic plate-like member of FIGS. 3 and 4 is replaced with a plate-like member 126 having protrusions. FIG. 5 shows a second embodiment of the present invention in a closed state, in which the pressure on the plate-like member 126 and the pressure on the head 104 are substantially equal. ing. By providing the protrusion 128 on the plate member, the speed at which the valve plate member 126 can close the valve is changed.

  FIG. 6 shows a third embodiment of the present invention. In this embodiment, the valve stem portion 102 is formed from a part of the urging member 120. The biasing member of FIG. 6 includes a substantially flat portion 130 and a bar portion 132 formed integrally with the flat portion 130. The bar 132 has a generally cylindrical portion and has several grooves 134 and ridges 136 on its surface. The valve head 104 is disposed at one end of the rod portion 132.

  As described above with reference to FIG. 5, the force applied by the valve plate-like member (and thus the speed at which the valve closes) can be adjusted by providing the plate-like member 126 having the protrusions. However, it should be noted that the maximum thickness of the protruding portion that can be used and the position of the protruding portion on the plate-like member are limited. 6-8, further embodiments of the present invention are provided, in which the bar portion 102 is replaced with an extension of the flat portion 130 of the biasing member 120 (bar portion 132). . The bar 132 provides greater flexibility with respect to the placement of the groove elements, and also provides greater flexibility with respect to the force that the biasing member can exert on the valve head 104.

  7 and 8 are similar to each other. In these embodiments, the biasing member 120 is formed on the rod portion 132, and the valve head 104 has an annular structure, and the structure thereof is the first of the rod portion 132 of the biasing member 120. The shape is configured to complement the portion 138. 7 and 8, the valve head 104 is held by the first portion 138 of the biasing member bar 132.

  7 and 8 also includes a second portion 140 having several grooves 134 and ridges 136 on the surface thereof. The biasing member in FIGS. 7 and 8 also includes a flat portion 130.

  7 and 8, an alternative method of attaching the biasing member 120 to the valve head 104 is provided. 3 to 6, the valve stem portion 102 or the valve head portion 104 is welded to the biasing member 120. Because of the configuration of these embodiments, the joint surfaces cannot be seen, so that the installation work is difficult to manage with low-cost production equipment.

  However, in FIGS. 7 and 8, the rod 132 protrudes through the annular valve head 104 so that the rod is visible from the outside. This makes it possible to use a fixing method that is cheap and is a manufacturing operation that is more easily managed and is attached by crimping.

  It should be noted that in FIGS. 6-8, the mass contained within the valve device is reduced compared to FIGS. 3-5 and FIG. Therefore, in the embodiment of FIGS. 6-8, the response time of the valve may be faster.

  FIG. 9 provides a further embodiment of the invention in which the control orifices 54, 56, 58 are built into the biasing member 120 instead of within the spacer 52 (in other words, integrated). Has been. The biasing member 120 is thinner than the spacer 52, so that the manufacturing time and manufacturing cost for producing the control orifice are reduced.

  It will be understood that the embodiments described above are provided by way of illustration only and are not intended to limit the invention, the scope of the invention being defined in the appended claims. . It will also be appreciated that the above-described embodiments can be used individually or in combination.

DESCRIPTION OF SYMBOLS 10 Main-body part 11 Hole 12 Valve needle 18 Fuel supply path 22 Control chamber 44 Actuator 100 Valve apparatus 102 Valve-bar part 104 Valve head 106 Valve guide part 108 Hole 110 1st edge part 111 2nd edge part 112 Valve groove part 114 Flow path 120 Energizing member 124 Volume portion 126 Plate-like member having a ridge portion 130 Substantially flat elastic portion 132 Bar portion 134 Groove portion

Claims (14)

Used between the injector and moved between an open state forming a pressurized fuel flow path (114) from the control chamber of the injector to the low pressure discharge and a closed state closing the flow path A possible valve device (100),
A valve guide (106) disposed in the injection device and forming at least part of the flow path;
A valve head (104) that closes the first end (110) of the valve guide when the valve device is in the closed state;
A biasing member (120) for biasing the valve device toward the closed state;
The biasing member (120) includes a plate-like elastic member disposed in the valve guide portion, and defines a volume portion (124) on the end side opposite to the valve head in the valve guide portion.
Valve device.   The force acting on the valve head (104) due to the pressure of fuel in the valve guide is substantially equal to the force acting on the biasing member (120) due to the pressure of fuel in the valve guide. The valve device according to claim 1, wherein the force acting on the head and the force acting on the biasing member act in substantially opposite directions. The valve guide portion further includes a valve stem portion (102), and the valve head portion (104) is disposed at a first end of the valve stem portion (102), and the biasing member (120). Is disposed at the second end of the valve stem,
The valve device according to claim 1 or 2. In the closed state, the biasing member (120), said plate-like comprising a substantially flat elastic plate-like member as an elastic member, the valve device according to any one of claims 1 to 3. The said biasing member is a valve apparatus as described in any one of Claim 1 to 3 provided with the plate-shaped member (126) which has a protrusion part as said plate-shaped elastic member . The biasing member includes a substantially flat elastic portion (130) and a rod portion (132) as the plate-like elastic member , and the valve head (104) is a first end portion of the rod portion. The valve device according to claim 1, wherein the elastic portion is disposed at a second end portion of the rod portion.   The valve device according to claim 6, wherein the rod portion is substantially cylindrical and comprises a plurality of grooves (134).   The valve device according to claim 6 or 7, wherein the valve head is attached to one end of the rod portion.   The valve device according to claim 6 or 7, wherein the valve head is annular, and the rod portion protrudes through the valve head.   The valve guide (106) includes a hole (108) that opens at the first end (110), and a second end that is separated from the first end (110) in the hole (108). 10. The valve device according to claim 1, further comprising a valve groove portion (112) in the portion (111), wherein the biasing member (120) is disposed in the valve groove portion.   The valve device according to claim 10, wherein the valve groove (112) has a larger cross-sectional area than the hole (108).   The biasing member forms a partition across the valve groove (112), whereby the valve head (104) and the hole (108) are arranged on one side of the partition and the volume (124 The valve device according to claim 10 or 11, which is formed on the other side of the partition wall. Used between the injector and moved between an open state forming a pressurized fuel flow path (114) from the control chamber of the injector to the low pressure discharge and a closed state closing the flow path A possible valve device (100),
A valve guide (106) disposed in the injection device and forming at least part of the flow path;
A valve head (104) that closes the first end (110) of the valve guide when the valve device is in the closed state;
A biasing member (120) for biasing the valve device toward the closed state;
With
The biasing member (120) comprises an elastic member disposed within the valve guide, and defines a volume (124) within the valve guide,
The volume (124) is filled with fuel, the fuel return Ru is configured to be in fluid communication with the back-leak passage, the valve device. An injection device used for delivering fuel to a cylinder of an internal combustion engine,
A body (10) comprising a hole (11);
A valve needle (12) slidable in the hole (11) of the nozzle body (10);
An actuator (44);
A fuel supply path (18) for supplying pressurized fuel to the control chamber (22);
14. A valve device according to any one of the preceding claims, operable by the actuator (44) to allow fuel to flow from the control chamber (22) to a low pressure discharge. An injection device comprising: