Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
  • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
  • F02M61/20—Closing valves mechanically, e.g. arrangements of springs or weights or permanent magnets; Damping of valve lift
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
  • F02M2200/24—Fuel-injection apparatus with sensors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
  • F02M2200/30—Fuel-injection apparatus having mechanical parts, the movement of which is damped
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
  • F02M2200/30—Fuel-injection apparatus having mechanical parts, the movement of which is damped
  • F02M2200/304—Fuel-injection apparatus having mechanical parts, the movement of which is damped using hydraulic means
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
  • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
  • F02M61/161—Means for adjusting injection-valve lift

Definitions

• the invention relates to a damping device for an oscillating component, in particular a preferably designed as an injection valve valve of an internal combustion engine, which component is actuated hydraulically via an actuating piston, wherein the preferably loaded by a restoring force actuating piston adjacent to a pressure chamber, which via a working medium carrying a pressure line Pressure can be acted upon, wherein the Dämpfungseinrich- device is arranged in the pressure line.
• the invention relates to an optical displacement sensor for measuring the needle stroke of an oscillating valve stem of a globe valve, in particular the nozzle needle stroke of an injection device for an internal combustion engine, with an optical emitter and a light receiver, the light beam directed to a reflection region reciprocating with the valve stem is and wherein the reflected beam is detected in at least one stroke position of the valve stem by the light receiver.
• a damping device for effecting damping of the opening movement of a needle valve which is pressed by supplying fuel under pressure in a pressure control chamber down and lifted by discharging the fuel from the pressure control chamber.
• a damping element is slidably supported on the needle valve.
• a damping chamber is formed between the damping element and the needle valve and is filled with fuel. Through a branch passage, fuel can be taken from the interior of the damping chamber and discharged outside the chamber.
• the disadvantage is that in damping devices with a continuous damping characteristic, the closing or opening time of the valve needle is delayed so that shallower opening and / or closing edges of the Nadelhubkurve arise. For reasons of combustion optimization, steep opening and closing edges are desirable. High closing speeds, however, lead to high contact speeds of the valve needle on the valve seat, which adversely affects the life of the valve. In addition, it comes to disturbing sound effects.
• US 5,775,355 A describes a method for measuring the needle stroke of a valve, wherein a light beam is directed onto a reflective surface of the needle and the reflected beam is detected by a sensor. Issued and re- inflected beam are arranged substantially in the stroke direction of the needle. By differential measurement of the emitted and reflected light beam, the needle stroke can be determined.
• an optical measuring probe for the dynamic displacement measurement of moving parts with a light source and a photosensitive arrangement, and a plurality of optical fibers is known, which allows to record path-time functions without contact and without interference by the measuring device.
• the moving part to be measured in this case has at the measuring point a defined area with respect to its environment different reflection or absorption capacity. This ensures that the measuring light in the direction of movement of the part to be measured increases or decreases according to the function to be measured.
• the object of the invention is to avoid these disadvantages and to reduce the placement speed of an oscillating component on a seat, in particular a valve on the valve seat, without significantly delaying the closing duration of the valve.
• Another object of the invention is to measure the stroke of a valve stem of a lift valve in the simplest and most accurate manner possible.
• the damping device comprises a damping piston in a cylinder longitudinally displaceable between two end positions, wherein in the damping piston at least one extending substantially in the longitudinal direction of the damping piston damping channel is arranged, which two opposite end faces of the damping piston flows together, and wherein a throttle check valve is arranged in the damping channel, the throttle effect of which depends on the flow direction. It is preferably provided that a spring acts on the damping piston in the opening direction of the throttle check valve, which presses the damping piston into a first end position corresponding to the rest position.
• the seating speed of the valve seat can be substantially reduced, when the damping device is designed as a closing damper, wherein the throttle resistance of the throttle check valve in the flow direction of the working medium when opening the valve is substantially less than in the reverse direction.
• the starting position of the damping device is defined by acting on the damping piston in the opening direction of the throttle check valve, a spring which presses the damping piston in a first end position corresponding to the rest position.
• the pressure line is pressurized again, wherein the check valve is opened within the throttle piston.
• the actuation medium can thus be supplied very rapidly to the actuating piston both through the bypass line and through the opened non-return valve, as a result of which the valve is opened in accordance with the selected characteristic.
• the amount of pressure of the actuating medium is an essential parameter for the opening characteristic of the valve.
• the closing of the valve is initiated by lowering the pressure in the pressure line.
• the damping piston is displaced by its predefined stroke counter to the force of a counteracting spring up to a stop from an end position corresponding to the rest position into a second end position.
• the hydraulic medium is pushed back by the spring-loaded actuating piston.
• a high closing speed of the valve can be achieved in a first closing area.
• the closing damper also has an advantageous effect on the post-swinging of the valve after the opening process.
• a further improvement of the Nachschwing s after opening the valve can be achieved are when the damper is preceded by an opening damper, wherein the preferably constructed identical to the closing damper opening damper in comparison to the closing damper with respect to the flow is arranged oppositely oriented.
• the damping piston of the opening damper is held in a starting position by a spring counter to the opening flow direction of the working medium.
• the check valve of the opening damper closes in the opening flow direction of the working medium and opens in the closing direction of the working medium.
• the damping piston of the opening damper If the pressure in the pressure line increases, the damping piston of the opening damper is displaced against the force of the spring in its second end position, which is defined by a stop. By the deflection of the piston, the pressure downstream of the opening damper is transmitted freely, whereby the check valve of the closing damper is opened. During this phase, the opening pressure is transferred virtually unthrottled to the actuating piston of the nozzle needle, so that the valve needle is opened very quickly in the first opening phase.
• the damping piston of the opening damper rests against its stop, the sudden increase in pressure in the pressure line downstream of the opening damper is stopped or greatly reduced, since the actuating medium can only flow through the bypass channel of the opening damper. Due to the throttle resistance of the bypass channel, the opening characteristic is determined in the second opening phase of the valve needle. There is thus a slowing of the opening movement of the valve at the end of the opening phase, so that over- and Nachschwingerscheinept be largely prevented.
• the emitting and / or reflected light beam is approximately transversely, preferably 90 ° ⁇ 20 ° to the direction of movement of the valve stem and that the reflection region by at least two surface portions with different reflective properties on the lateral surface of the Valve stem is formed. It is provided that at least a first surface portion has a reflection-poor, preferably black coating, and that at least a second surface portion is reflective strong, preferably formed as a ground and / or polished surface.
• a particularly compact design and space-saving accommodation of the optical displacement sensor results in particular in an injection device for an internal combustion engine, when the housing of the lift valve has a preferably formed by a hole window, which is arranged in the region of the dividing line between the two reflective surface portions of the oscillating element laterally , To be able to make exact measurements, it is advantageous if the height of the window corresponds at least to the stroke of the valve stem.
• a simple retrofitting and accurate fixing is possible when a preferably consisting of two half-shells sensor housing on the housing of Hubeventils captive, preferably non-positively attachable, preferably wherein the sensor housing has a light channel whose longitudinal axis is arranged transversely to the direction of movement of the valve stem, and preferably is connected via at least one optical conductor with a light source and / or a light receiver.
• the light channel is arranged in alignment with the window in the housing of the lift valve.
• a sapphire lens For media separation and sealing of the measuring range, provision may be made for a sapphire lens to be arranged in the light channel following at least one optical conductor, wherein the sapphire lens is preferably soldered.
• the displacement sensor measures optically the stroke of the valve stem, wherein the reflection strength of the transmitted light to the measuring point is used as a measure of the stroke.
• the measuring point is prepared in such a way that it is subdivided into a reflection-intensive and a reflection-poor surface.
• the imaginary dividing line of both surfaces is ideally normal to the direction of movement of the part to be measured.
• the light emitted by the light source is passed through glass fibers, as well as the light receiver reaching the reflected light.
• FIGS. show schematically:
• FIG. 1 shows a variant of a damping device according to the invention in a longitudinal section.
• FIGS. 2 to 7 show an inventive damping device for an oscillating component in various positions
• FIG. 10 shows an injection device in a longitudinal section with an optical path measuring device according to the invention
• FIG. 11 shows the injection device in a cross section according to the line XI-XI in FIG. 10;
• the damping device 7 is suitable for oscillating components, in particular for valves 1, for example for an outwardly opening injection valve 2 of an internal combustion engine.
• Fig. 1 shows an injection valve 2 with a damping device 7 for an internal combustion engine.
• the valve 1 of the injection valve 2 is opened by a longitudinally displaceable actuating piston 3 by means of a hydraulic working medium and closed by a closure force F on the actuating piston 3 performing closing spring 4.
• the axially longitudinally displaceable actuating piston 3 is adjacent to a pressure chamber 5, in which opens a pressure line 6 for the working fluid.
• a damping device 7 designed as a closing damper 25 is arranged in the pressure line 6.
• the damping device 7 has a longitudinally displaceable in a cylinder 8 damping piston 9, which is held by a spring 10 in a rest position corresponding first end position, as shown in Fig. 1 can be seen.
• a damping channel 11 is arranged, which connects the two end faces 12, 13 of the damping piston 9 together flow, wherein the end faces 12, 13 adjoin spaces, in which the pressure line 6 opens.
• a throttle check valve 14 is arranged, which is formed in the embodiment by a by-passable via a bypass passage 15 check valve 16.
• the check valve 16 is pressed by a valve spring 17 against the effective direction of the spring 10 against a valve seat 18, wherein in the closed state of the check valve 16, the flow around the bypass channel 15 is possible.
• the bypass channel 15 has a defined throttle resistance, which is indicated by the reference numeral 19 in Fig. 2 to Fig. 8. With reference numeral 20, the throttle resistance of the damping channel 11 is designated.
• a control valve 21 is arranged in the pressure line 6.
• the damping piston 9 has a diameter di and can be moved within the cylinder 8 by the stroke hi.
• the reference numerals d 2 and h 2 , the diameter, or the stroke of the actuating piston 3 are designated.
• the check valve 16 opens in the flow when opening the valve needle 1 from the working fluid direction.
• Fig. 9 is a lift curve of the valve 1 is shown, wherein the stroke h is plotted against the time t.
• the stroke h is plotted against the time t.
• the arrows II, III, IV, V, VI and VII different opening phases of the valve 1 are shown according to Figures 2 to 7.
• the actuating piston 3 is loaded by a force F in the closing direction of the valve 1, for example by the closing fields 4.
• the damping piston 9 is in its by the spring 10 defined first end position, which corresponds to its rest position, the check valve 16 is closed.
• the closing operation of the valve 1 in accordance with arrow V in FIG. 9 is initiated by reducing the pressure in the pressure line 6 via the control valve 21, as shown in FIG. 5, so that P B ⁇ P A ⁇
• a first closing phase 22 the damping piston 9 according to the arrow Pi against the force of the spring 10 due to the pressure difference P A -P B on both sides of the damping piston 9 shifted upward until the damping piston 9 rests against a stop 24.
• the hydraulic medium is thereby pushed back by the prestressed actuating piston 3 in the pressure line 6, wherein the actuating piston 3 moves with the medium.
• the movement of the medium is designated P 2 .
• the stroke h 2 of the damping piston 9 must be such that the damping piston 9 rests against the stop 24 before the valve 1 strikes its valve seat. After resting the damping piston 9 on the stop 24, the pressure p A increases rapidly in the working space 5. The pressure p A can be reduced only slowly corresponding to the throttle resistance 19 of the bypass channel 11, which is why a significant slowing down of the closing movement of the valve 1 occurs.
• This second closing area is designated 23 in FIG.
• the corresponding phase of the damping device 7 is shown in FIG. By suitable tuning of the throttle resistors 19, 20 is too hard Opening the valve 1 prevents the valve seat, but still allows a total of fast closing within a short period of time.
• the opening damper 26 is of identical design to the closing damper 25, but arranged inversely oriented in the pressure line 6, wherein the check valve 16a of the throttle check valve 14a now opens against the direction which flows through the working fluid when opening the valve 1.
• the spring 10a of the opening damper 26 acts on the damping piston 9a of the opening damper 26 in a direction opposite to the spring 10 so that it is pressed counter to the opening flow direction of the working medium in a rest position corresponding to its first end position.
• the direction of the rest position is indicated in Fig. 8 by the arrows 27, 28.
• the action of the opening damper 26 is analogous to FIGS. 2 to 7, but in the opposite direction. If pressure is applied to the pressure line 6, the damping piston 9a of the opening damper 26 is moved out of the rest position against the force of the spring 10a until the damping piston 9a bears against the stop 24a. During this phase, the opening pressure prevails in the pressure line 6 downstream of the opening damper 26 unhindered, the check valve 16 of the damper 25 is opened and opened as a result of the valve 1 by the increasing pressure in the pressure chamber 5 very quickly.
• an injection device 101 forming the lift valve comprises a housing 102 in which a reciprocable valve stem 103 is arranged.
• an optical Displacement sensor 110 is provided for measuring the needle stroke h.
• the optical measuring device 110 has a light source (not shown) and a light receiver, not shown, which is formed by a photosensitive element.
• the light source and the light receiver are coupled to the injection device 101 via a light guide 111 or via optical fibers, wherein optical fibers 111 and / or optical fibers open into a sensor housing 112 consisting of half shells 112a, 112b, which surrounds the housing 102 of the injection device 101.
• the sensor housing 112 has a light channel 113 which is arranged coaxially with respect to a radial window 104 formed in the housing 102 of the injection device 101 by a bore.
• a sapphire lens 114 is attached, for example, soldered.
• the valve stem 103 has a lateral surface 103a with at least two surface portions 105, 106 with different reflection properties.
• the reflection-weak first surface portion 105 is formed by a black coating, the reflecting second surface portion 106 by a ground or polished spot. Between the first and the second surface portion 105, 106 a sharp dividing line 107 is provided, which is arranged substantially normal to the stroke axis 103 'of the valve stem 103.
• the injection device 101 is embodied in the exemplary embodiment as a modern diesel common rail injector with a short valve stem 103 and a compact construction.
• the measuring point for the needle stroke h is located on the valve stem 103 at a distance from the injection nozzle tip 108.
• the injector 101 is permanently under constant fuel pressure (up to 1600 bar and above) during operation, so it is relatively difficult from the outside measuring light to the measuring point and again to lead back. This is done by means of the radial window 104 formed by a bore, around which the sensor housing 112 is arranged.
• the two half-shells 112a, 112b of the sensor housing 112 are connected to one another by screws 116 and the sensor housing 112 is thus clamped onto the housing 102 of the injector 101.
• the sensor housing 112 assumes the function of optical signal transmission.
• the soldered and ground at the faces sapphire optics 114 separates the pressurized fuel in the volume 109 from the environment, while allowing a light signal transmission.
• Important is a corresponding contact pressure of the half-shells 112a, 112b of the sensor housing 112 acting on the sealing surface 117 of the half-shell 112b to ensure a secure seal.
• the light guides 111 which are guided as a glass fiber bundle in a thin tube, are positioned directly adjacent to the sapphire lens 114 to guarantee optimum light transmission.
• the height d of the window 117 should be larger, advantageously twice as large as the maximum stroke h of the valve needle 103 to allow measurement in a reasonably linear range.
• the area of the maximum stroke h should be aligned as centrally as possible to the window 117. Ideally, a calibration curve is taken to linearize the lift curve.
• FIG. 12 shows an example of an evaluation of a needle stroke h of the valve stem 103 of an injection device 101.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Valve Device For Special Equipments (AREA)
• Fuel-Injection Apparatus (AREA)
• Fluid-Damping Devices (AREA)
• Glass Compositions (AREA)
• Noodles (AREA)
• Control Of Motors That Do Not Use Commutators (AREA)
• Length Measuring Devices By Optical Means (AREA)

Applications Claiming Priority (3)

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• 2007
  • 2007-06-13 JP JP2009514592A patent/JP5042309B2/ja not_active Expired - Fee Related
  • 2007-06-13 DE DE502007005050T patent/DE502007005050D1/de active Active
  • 2007-06-13 WO PCT/AT2007/000288 patent/WO2007143770A2/fr active Application Filing
  • 2007-06-13 AT AT07718499T patent/ATE481567T1/de active
  • 2007-06-13 EP EP07718499A patent/EP2027387B1/fr not_active Not-in-force

Non-Patent Citations (1)

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