JP5042309B2 - Damper mechanism for continuously reciprocating structural parts - Google Patents

Abstract

The invention relates to a damping device (7, 7a) for an oscillating component, in particular a valve (1), which is preferably an injection valve (2), of an internal combustion engine, said component being able to be hydraulically actuated by means of an actuation piston (3), wherein the actuation piston (3), preferably loaded with a restoring force (F), borders a pressure chamber (5) which can be charged with pressure by means of a pressure line (6) which carries a working medium, wherein the damping device (7, 7a) is arranged in the pressure line (6). In order to extend the service life while maintaining high opening and closing speeds, it is proposed that the damping device (7, 7a) has a damping piston (9, 9a) which can be longitudinally displaced in a cylinder (8, 8a) between two end positions, wherein at least one damping channel (11, 11a) is arranged in the damping piston (9, 9a), extending essentially in the longitudinal direction of the damping piston (9, 9a), which propvides a fluid connection between two opposing face sides (12, 13) of the damping piston (9, 9a) and wherein a one-way-restrictor (14, 14a) is arranged in the damping channel (11, 11a), the choke effect of which depends on the direction of flow.

Description

The invention relates to a damper mechanism for a continuously reciprocating structural component that can be hydraulically actuated via a movable valve body, particularly preferably a valve formed as an injection valve of an internal combustion engine, preferably biased by a restoring force said movable valve body which is adjacent to the pressure chamber is pressure supplied through pressure line through which the working medium, related to the damper mechanism of the type that is disposed in the pressure line.

  From European Patent No. 1335125 (Patent Document 1), opening and closing of a needle valve configured to be pushed downward by supply of pressurized fuel to a pressure control chamber and lifted by discharge of fuel from the pressure control chamber A damper mechanism for braking operation is known. This damper mechanism is slidably held by the needle valve. A pressure chamber is formed between the damper mechanism and the needle valve and is filled with fuel. Fuel is withdrawn from the interior of the pressure chamber through the shunt and guided out of the chamber. This damper mechanism can give a constant braking to the valve needle stroke.

  The damper mechanism having a stable braking characteristic is disadvantageous in that the opening / closing operation time of the valve needle is delayed, so that the opening stroke on the needle stroke curve and / or the closing curve on the closing stroke side is flattened. For combustion optimization, a steep open operation side up curve and / or a closed operation side down curve is desirable. However, a high closing speed results in the valve needle contacting the valve seat at a high speed, which adversely affects the durable life of the valve. In addition, troubles due to noise effects also occur.

  U.S. Pat. No. 5,755,355 (Patent Document 2) discloses a valve needle stroke measuring method in which a light beam is directed to a reflecting surface of a needle and the reflected light beam is detected by a sensor. In this method, the illuminating light beam and the reflected light beam are substantially directed in the direction of the needle stroke. It is possible to calculate the needle stroke by measuring the difference between the irradiated light and the reflected light.

  German Offenlegungsschrift No. 10257955 (Patent Document 3) discloses a vibration damper in which a braking distance measurement of the type in which an illuminating device and a light receiving device of an optical measuring system are mounted on a stationary element is performed. The measurement light from the illumination unit irradiates an element that is movable relative to the first element of the vibration damper. The reflected light is detected by the light receiving unit of the optical measurement system and evaluated as an incremental displacement by the image data processing method in the evaluation unit. This enables optical distance measurement for vibration dampers that require high accuracy and high reliability signal generation.

  Furthermore, from German Patent No. 1930111 (Patent Document 4), a movable part including a light source, a light receiving unit and a number of light guides capable of non-contact and distance-time-function measurement unaffected by the measuring device. An optical measurement probe for performing dynamic distance measurement is known. Here, the movable part to be measured has a predetermined area at the measurement location, which has a different reflection or absorption rate compared to the surroundings. As a result, the measuring light increases or decreases depending on the function to be measured in the direction of movement of the part to be measured.

European Patent Publication No. 1335125 US Pat. No. 5,755,355 German published patent publication No. 10257955 German Patent Publication No. 1930111

The object of the present invention is to avoid the disadvantages described above, reduce the contact speed of structural parts that reciprocate continuously, particularly the seating speed of the valve on the valve seat, and not significantly delay the valve closing operation time. Ru der it to.

According to the present invention, the object is to provide a bumper valve body in which the damper mechanism can slide between two end positions in the cylinder portion in the longitudinal direction, and the bumper valve body substantially includes the bumper valve body in the longitudinal direction. And at least one bumper passage that is in fluid communication with each other on the two opposite end face sides of the bumper valve body is disposed, and a one-way throttle valve whose throttling action depends on the flow direction is disposed in the bumper passage. The one-way throttle valve includes a check valve that is opened by an increase in pressure in the pressure line, and a bypass that bypasses the check valve when the movable valve body moves to the closed position in response to a decrease in the pressure of the working medium. And the detour is provided with an aperture resistor .

  Preferably, the bumper valve body is configured such that a spring force that biases the bumper valve body acts on a first end position corresponding to a stationary position in the opening direction of the one-way throttle valve.

  In the case of a continuously reciprocating structural component configured as a valve, the damper mechanism is formed as a closed damper, and the throttle resistance of the one-way throttle valve in the flow direction of the working medium during the opening operation of the valve is in the reverse direction If it is much smaller than the throttle resistance, the seating speed of the valve on the valve seat can be greatly reduced.

  The initial position of the damper mechanism is set by applying a spring force that biases the bumper valve body to a first end position corresponding to a stationary position in the opening direction of the one-way throttle valve on the bumper valve body. . Pressure is again supplied to the pressure line during the opening operation stroke of the valve, and the check valve inside the bumper valve body is opened. Therefore, the working medium can be supplied to the movable valve body very rapidly, whether through the bypass or through the opened check valve, so that the valve is selected. The opening operation is performed according to a predetermined characteristic. The pressure level of the working medium is an important adjustment parameter for the valve opening characteristics.

  The valve closing process is initiated by depressurization of the pressure line. At this time, the bumper valve body is displaced by a predetermined stroke from the end position corresponding to the stationary position to the second end position until it comes into contact with the stopper against the force of the spring acting in the opposite direction. At that time, the pressure medium liquid is pushed back by the movable valve body biased by the spring. Thereby, the high closing operation speed of the valve is achieved in the first closing operation region. At the same time that the bumper valve body abuts against the stopper, the working medium can only flow out through a bypass route that bypasses the check valve. The seating speed of the valve is determined by the area. Accordingly, the second closing operation region is generated when the flow of the working medium is largely restricted by the bypass in the bumper valve body. After the valve is seated on the valve seat and a pressure balance occurs on both sides of the bumper valve body, the bumper valve body is brought back to its initial position by a spring.

  It has been found that the closing damper also has an advantageous effect on the undershoot of the valve after the opening operation process. The further improvement of the undershoot characteristic after the opening operation of the valve is that an opening damper is placed in front of the closing damper, and an opening damper preferably formed structurally equal to the closing damper is compared with the closing damper. This is possible by arranging them in the opposite direction in terms of flow. In this case, the bumper valve body of the open damper is held at the initial position by the spring in the direction opposite to the flow direction of the working medium to open. The check valve of the open damper is closed in the flow direction of the working medium to open, and opened in the flow direction of the working medium to close. When the pressure in the pressure line increases, the bumper valve body of the open damper is displaced to the second end position determined by the stopper against the force of the spring. Due to the displacement of the piston, the pressure is transmitted to the downstream side of the open damper without any trouble, thereby opening the check valve of the closed damper. During this phase, the opening pressure is transmitted to the movable valve body of the nozzle needle without actually being throttled, so that the valve needle is opened very quickly in the first opening operation process. At the same time that the bumper valve body of the open damper abuts against the stopper, the working medium can only flow in through the bypass of the open damper, so that a sudden pressure increase in the pressure line is caused on the downstream side of the open damper. Can not be stopped or greatly reduced. The opening operation characteristic in the second opening operation process of the valve needle is determined by the throttle resistance of the bypass. Thus, the valve opening operation is slowed down at the end of the opening operation process, so that over and undershoot phenomena are substantially prevented.

It is a figure which shows the longitudinal cross-section of one embodiment of the damper mechanism by this invention. FIG. 4 shows a damper mechanism according to the invention for a structural component that is continuously reciprocating in various different positions. FIG. 4 shows a damper mechanism according to the invention for a structural component that is continuously reciprocating in various different positions. FIG. 4 shows a damper mechanism according to the invention for a structural component that is continuously reciprocating in various different positions. FIG. 4 shows a damper mechanism according to the invention for a structural component that is continuously reciprocating in various different positions. FIG. 4 shows a damper mechanism according to the invention for a structural component that is continuously reciprocating in various different positions. FIG. 4 shows a damper mechanism according to the invention for a structural component that is continuously reciprocating in various different positions. It is a figure which shows the longitudinal cross-section of the damper mechanism of the embodiment of another structure. It is a figure which shows a valve stroke curve.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  The damper mechanism 7 is suitable for a structural part that continuously reciprocates, particularly a valve 1, for example, an internal combustion engine injection valve 2 that opens outward. FIG. 1 shows an injection valve 2 with a damper mechanism 7 for an internal combustion engine. The valve 1 of the injection valve 2 is opened by a movable valve body 3 that can slide in the longitudinal direction by a hydraulic working medium, and is closed by a closing operation spring 4 that applies a closing operation force F to the movable valve body 3. . The movable valve body 3 that can slide in the vertical axis direction is in contact with the pressure chamber 5, and a pressure line 6 for the working medium joins the pressure chamber.

  FIGS. 2 to 7 show the form of the movable valve body 3 at each position linked to a structural component that reciprocates continuously. A damper mechanism 7 formed as a closed damper 25 in the pressure line 6 is shown. Is arranged. The damper mechanism 7 has a bumper valve body 9 that can slide in the longitudinal direction in the cylindrical portion 8, and the bumper valve body is, as can be seen from FIG. 1, a first end position corresponding to a stationary position by a spring 10. Retained. Inside the bumper valve body 9 is disposed a bumper flow path 11 that fluidly communicates both end face sides 12 and 13 of the bumper valve body 9 with each other, and the end face sides 12 and 13 are chambers in which the pressure line 6 joins. Is in contact with In this embodiment, a one-way throttle valve 14 formed as a check valve 16 that can be bypassed via a bypass circuit 15 is disposed in the bumper flow path 11. The check valve 16 is pressed toward the valve seat 18 by the valve spring 17 in the direction opposite to the direction of action of the spring 10, and a bypass flow is possible via the bypass circuit 15 in the closed state of the check valve 16. . The bypass 15 has a predetermined aperture resistance indicated by reference numeral 19 in FIGS. The throttle resistance of the bumper flow path 11 is denoted by reference numeral 20.

A control valve 21 is disposed in the pressure line 6 upstream of the damper mechanism 7. The bumper valve body 9 has a diameter d ₁ and can slide within the cylinder portion 8 by a stroke h ₁ . The diameter or stroke of the movable valve body 3 is represented by the symbols d ₂ and h ₂ , respectively.

  In the damper mechanism 7 formed as the closed damper 25, the check valve 16 is opened in the direction in which the working medium flows when the valve needle 1 is opened.

  In FIG. 9, the stroke curve of the valve 1 is represented. In the figure, the stroke h is represented in correlation with the time t. Arrows II, III, IV, V, VI and VII represent various opening and closing processes of the valve 1 corresponding to FIGS.

  FIG. 2 shows a stationary state of the valve 1 corresponding to the arrow II in FIG. The movable valve body 3 is loaded by the force F in the closing operation direction of the valve 1, for example, by the closing operation spring 4. The bumper valve body 9 is in a first end position corresponding to a predetermined stationary position by a spring 10, and the check valve 16 is closed.

FIG. 3 shows a process of opening the valve 1 corresponding to the arrow III in FIG. When the pressure P _{B in} the pressure line 6 rises to the pressure P _Medium , the check valve 16 is opened, and thereby the maximum possible working medium flow continuous to the bumper flow path 11 in the bumper valve body 9 is cut off. The area is released (P _B > P _A ). The resulting increase in pressure in the pressure chamber 5 causes the movable valve body 3 to move downward in response to the arrow P in FIG. 3, and thus the valve 1 is opened. When the valve 1 is fully opened (arrow IV in FIG. 9), a pressure balance P _A = P _B occurs on both end face sides 12, 13 of the bumper valve body 9, so that the check valve 16 is a valve spring 17. (FIG. 4). In this phase, the pressure P _Medium is maintained in the pressure line 6. The closing operation process of the valve 1 corresponding to the arrow V in FIG. 9 is started by depressurization of the pressure line 6 through the control valve 21, as shown in FIG. 5, and thus P _B <P _A Become. In the first closing operation process 22, the bumper valve body 9 is stopped by the bumper valve body 9 against the force of the spring 10 according to the pressure difference P _A -P _B on both end face sides of the bumper valve body 9. It is slid upwards until it abuts in correspondence with the arrow P ₁ in. At that time, the pressure medium liquid is pushed back into the pressure line 6 by the prestressed movable valve body 3, and the movable valve body 3 also moves together with the pressure medium liquid. Movement of the pressure medium liquid is represented by P _2. Stroke h ₂ of the bumper valve body 9, bumper valve body 9 before the valve 1 is seated on the valve seat must be dimensioned so as to abut against the stopper 24. After bumper valve body 9 is in contact with the stopper 24, the pressure P _A in the working chamber 5 rises rapidly. Since the pressure P _A that is alleviated gradually in accordance with the throttle resistance 19 of bypass 11, significant slowing of closing operation of the valve 1 occurs. This second closing operation region is denoted by reference numeral 23 in FIG. This phase of the damper mechanism 7 is shown in FIG. By appropriately adjusting the throttle resistances 19 and 20, the valve 1 can be prevented from excessively striking the valve seat, and nevertheless, a rapid closing operation in a short time as a whole is possible. Can do.

After elimination of both sides of the pressure difference P _A -P _B bumper valve body 9, the bumper valve body 9 spring 10, as represented in Figure 7, is caused to return to the rest position again.

  Due to the closing damper 25, the valve vibration movement after the opening operation of the valve 1 is also reduced. Further reduction of the undershoot of the valve 1 can be achieved when an open damper 26 is placed in front of the closed damper 25 in the pressure line 6 as represented in FIG. The open damper 26 is formed structurally equal to the closed damper 25, but is disposed in the opposite direction to the pressure line 6, so that the check valve 16a of the one-way throttle valve 14a is open to the valve 1. It opens in the direction opposite to the direction in which the working medium flows during operation. Since the spring 10a of the open damper 26 acts on the bumper valve body 9a of the open damper 26 in the direction opposite to the spring 10, the bumper valve body is in a stationary position in the direction opposite to the direction in which the working medium opens. To the first end position corresponding to. The direction of the rest position is indicated by arrows 27 and 28 in FIG.

  The operation of the open damper 26 is carried out in the same way as in FIGS. When pressure is applied to the pressure line 6, the bumper valve body 9a of the open damper 26 is moved from the stationary position until the bumper valve body 9a contacts the stopper 24a against the force of the spring 10a. During this phase, the opening operation pressure of the pressure line 6 is provided without any trouble downstream of the open damper 26, the check valve 16 of the closed damper 25 is opened, and then the pressure in the pressure chamber 5 is increased. The valve 1 is opened very quickly. As soon as the bumper valve body 9a of the open damper 26 abuts against the stopper 24a, the opening operation of the valve 1 is very slow since the subsequent pressure buildup is determined by the throttle resistance 19a of the bypass 15a of the open damper 26. Is done. As a result, overshoot of the valve 1 is prevented. When the valve stroke of the valve 1 is completely achieved, pressure balance is generated on both sides of the bumper valve body 9a, so that the bumper valve body 9a is returned to the rest position again by the spring 10a corresponding to the arrow 28. Subsequently, as already described with reference to FIGS. 2 to 7, a closing operation process occurs.

Claims (5)

The movable valve body (3) with hydraulic operable continuously reciprocating to combustion engine injection valve within a structural unit goods damper mechanism for the valve is formed as a (2) (1) (7, 7a) through the The movable valve body (3) biased by the restoring force (F) is adjacent to the pressure chamber (5) supplied with pressure through the pressure line (6) through which the working medium passes, and the damper mechanism (7 7a) in the damper mechanism arranged in the pressure line (6),
The damper mechanism (7, 7a) has a bumper valve body (9, 9a) capable of sliding in the vertical direction between two end positions in the cylindrical portion (8, 8a), and the bumper valve body (9, 9a) at least one bumper flow extending in the longitudinal direction of the bumper valve body (9, 9a) and in fluid communication with two opposite end face sides (12, 13) of the bumper valve body (9, 9a) A path (11, 11a) is arranged, and a one-way throttle valve (14, 14a) whose throttle action depends on the flow direction is arranged in the bumper flow path (11, 11a) ,
The one-way throttle valve (14, 14a) includes a check valve (16, 16a) opened by the pressure increase in the pressure line (6), and the movable valve body (3 ) Is provided with a detour (15, 15a) that bypasses the check valve (16, 16a) when heading to the closed position, and a throttling resistor is provided in the detour (15, 15a). A damper mechanism (7, 7a). A spring (10, 10a) acting in the opening direction of the one-way throttle valve (14, 14a) with respect to the bumper valve body (9, 9a) is provided, and the spring (10, 10a) is the bumper valve body. The damper mechanism (7, 7a) according to claim 1 , wherein (9, 9a) is urged to a first end position corresponding to a stationary position. The stroke (h2) of the bumper valve body (9, 9a) is such that the bumper valve body (9, 9a) before the valve (1) is seated on the valve seat corresponding to the closed position of the valve (1). 3. The damper mechanism (7, 7 a) according to claim 1 or 2 , wherein the damper mechanism (7, 7 a) is dimensioned so as to abut against a stopper (24) on the side corresponding to the closed position of the valve (1 ). The damper mechanism (7, 7a) is formed as a closed damper (25), and the throttle resistance of the one-way throttle valve (14) in the flow direction of the working medium during the opening operation of the structural component is the throttle resistance in the reverse direction. The damper mechanism (7, 7a) according to any one of claims 1 to 3 , wherein the damper mechanism (7, 7a) is smaller. An open damper (26) is placed in front of the closed damper (25), and the open damper (26), which is structurally equal to the closed damper (25), has a flow more than that of the closed damper (25). Damper mechanism (7, 7a) according to claim 4 , characterized in that it is arranged in the opposite direction at the point.

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