Method for preventing throttle actuator failure, throttle actuator, computer program, and computer readable medium

Abstract

The invention relates to a method for preventing a malfunction of a throttle actuator (3), wherein a vibration movement is performed by a throttle (5a, 5b, 5c) of the throttle actuator (3). The invention further relates to a throttle actuator (3), a computer program (4b) and a computer readable medium (4a).

Description

Technical Field

[0001] This invention relates to a method for preventing throttle actuator failure, particularly applicable to throttle actuators in fuel cell systems; the invention also relates to a throttle actuator, a computer program, and a computer-readable medium. Background Technology

[0002] In low ambient temperatures, if liquid accumulates on valve components (especially the throttle valve in a fuel cell system), it can freeze, which can cause throttle valve actuator malfunction because the throttle valve cannot operate when it is frozen.

[0003] Prior art document EP 3 252 362 A1 discloses a heatable throttle valve, which can prevent the throttle valve from freezing or be used to defrost a frozen throttle valve.

[0004] The drawback of this solution is that it requires a dedicated heating device, and power is needed to drive the heating device. Summary of the Invention

[0005] One object of the present invention is to provide an alternative, particularly a method for preventing throttle body icing without the need for complex devices. Another object is to provide a throttle body actuator suitable for performing this method.

[0006] Another objective is to provide a computer program that includes instructions to cause a throttle actuator to perform the method.

[0007] Another objective is to provide a computer-readable medium storing the said computer program.

[0008] According to one embodiment of the present invention, a method for preventing throttle actuator failure is provided, preferably for use in a fuel cell system, wherein the throttle actuator includes a throttle valve movable between an open position and a closed position, the method comprising: performing a vibratory motion through the throttle valve.

[0009] This vibration removes (especially shakes off) the liquid that accumulates on the throttle body, thus reliably preventing throttle body icing without the need for complex heating devices.

[0010] Preferably, the throttle valve is disposed in the flow channel; by positioning the throttle valve in different positions, the flow cross-section of the flow channel can be changed, that is, the flow cross-sectional area of ​​the flow channel depends on the position of the throttle valve in the flow channel. Preferably, the flow channel is part of the throttle valve actuator; more preferably, the flow channel is integrally formed with the housing of the throttle valve actuator.

[0011] Preferably, the fault to be prevented is throttle body icing, particularly icing at the throttle body seat; this icing is especially likely to occur at low ambient temperatures, and prior to this, liquid (preferably water) has accumulated in the throttle body area due to condensation.

[0012] Preferably, the open position refers to the position where the throttle valve is in a position that maximizes the flow cross-sectional area of ​​the flow channel; the closed position refers to the position where the throttle valve is in a position that minimizes the flow cross-sectional area of ​​the flow channel, or a position that completely closes the flow channel, and / or the position of the throttle valve under the return force of the return spring of the throttle valve actuator. In other words, the closed position can be the stationary position of the throttle valve; preferably, the stationary position refers to the position of the throttle valve when the electric drive of the throttle valve actuator is not energized (i.e., in a deactivated state).

[0013] Preferably, the throttle valve is connected to the throttle valve shaft in a manner that transmits torque; preferably, the throttle valve shaft can be driven by an electric drive (especially an electric motor, preferably the electric motor or electric drive of the throttle valve actuator); preferably, a gear transmission mechanism is provided between the electric motor and the throttle valve shaft to transmit the rotation of the electric motor to the throttle valve shaft and then to the throttle valve.

[0014] In a preferred embodiment, the method is performed when or after the fuel cell system is shut down. This reliably prevents the throttle valve (preferably in its stationary position) from freezing, as moisture can accumulate due to condensation, particularly in the throttle valve area, when the fuel cell system is shut down.

[0015] In another preferred embodiment, the method is initialized after a period of time following the shutdown of the fuel cell system. This ensures that condensation and the resulting liquid buildup in the throttle region are substantially complete before the method is executed, thereby removing most of the liquid that could cause the throttle to freeze.

[0016] In this way, especially when the time interval is independent of the ambient temperature, the temperature sensor, the temperature sensor signal, or the evaluation of the temperature sensor signal can be omitted, thereby simplifying the method.

[0017] In another preferred embodiment, the method is initialized based on the ambient temperature of the throttle actuator, the fuel cell system, or the vehicle including the throttle actuator or the fuel cell system. In other words, the method may not be performed when the ambient temperature is high enough that the throttle is unlikely to freeze or can be deflated.

[0018] Preferably, the method is performed only when the ambient temperature is below 4°C, or has been below 4°C in the past 24 or 72 hours. Of course, other threshold temperatures can be used, as long as the possibility of throttle body icing can be considered. Typically, icing of the throttle body in its stationary position (preferably at its throttle seat) can be considered.

[0019] Preferably, the ambient temperature is measured by a temperature sensor; more preferably, the temperature sensor can be a temperature sensor of another system in the vehicle (i.e., a non-fuel cell system), thereby eliminating the need for a dedicated temperature sensor.

[0020] Preferably, the temperature sensor provides a temperature sensor signal that can be evaluated by the control unit; based on the evaluation result, the control unit initializes the method. Regardless of whether a temperature sensor is used, preferably, the control unit is capable of starting, triggering, and / or terminating the method.

[0021] Preferably, the time interval between the shutdown of the fuel cell system depends on the ambient temperature of the throttle actuator, the fuel cell system, or the vehicle including them.

[0022] In another preferred embodiment, the vibration motion includes at least one movement of the throttle valve toward the open position and / or at least one movement of the throttle valve toward the closed position; preferably, the vibration motion is a reciprocating motion of the throttle valve between the open and closed positions, and preferably includes acceleration. Preferably, the vibration motion is performed using only a portion of the throttle valve's full travel; preferably, the method uses at most 60%, at most 40%, or at most 20% of the throttle valve's full travel; or preferably, the method uses at least 10%, at least 30%, or at least 50% of the throttle valve's full travel.

[0023] Generally speaking, within the scope of this invention, the term "location" can also be understood as "direction" or vice versa.

[0024] Preferably, before performing the vibration movement through the throttle valve, the throttle valve is first moved to a position between the open and closed positions. This provides the throttle valve with sufficient travel to perform the vibration movement without being restricted by the mechanical limiter, thereby avoiding damage to the throttle valve actuator (especially its gear transmission mechanism or the throttle valve itself). The mechanical limiter may, for example, be defined and formed by the open and / or closed positions.

[0025] In another preferred embodiment, the vibration motion is generated by the electric drive of the throttle actuator and / or the return spring of the throttle actuator.

[0026] Preferably, the electric drive is a motor of a throttle actuator, which preferably transmits its rotation to the throttle valve via a throttle valve shaft; the motor is preferably controlled by a control unit. With the aid of a return spring, at least some vibrational movement can be achieved without the application of electrical energy. It is also conceivable that the throttle valve is moved to a first position by the electric drive to overcome the return force of the return spring, and then the electric drive is turned off, allowing the return spring to accelerate or move the throttle valve back to its initial or stationary position.

[0027] Typically, preferably, the vibration causes the throttle valve to accelerate in one direction (more preferably in two opposite directions, especially toward the open and closed positions).

[0028] In another preferred embodiment, the method is performed sequentially multiple times, particularly with time intervals between each execution. This ensures that the fluid is removed or shaken off substantially completely from the throttle body.

[0029] In another preferred embodiment, the vibration motion includes the impact motion of the throttle valve against its mechanical limiter. This can enhance the shaking effect of the method, but may come at the cost of reducing the lifespan of the throttle actuator (especially the throttle valve or its gear transmission mechanism).

[0030] In another preferred embodiment, the vibration motion includes the maximum acceleration of the throttle valve, which is selected to protect the throttle actuator from mechanical damage when the method is performed, thereby ensuring the lifespan of the throttle actuator.

[0031] In addition, or independently of the maximum acceleration, preferably, the vibrational motion includes the minimum acceleration of the throttle valve, thereby ensuring the removal of liquids that may cause the throttle valve to freeze at low ambient temperatures.

[0032] In another preferred embodiment, the throttle body remains in contact with the seal during vibratory motion. Preferably, the seal is a seal of a throttle actuator for the throttle body, and the throttle body abuts against the seal in the closed position. Preferably, when the throttle body abuts against the seal (i.e., in contact with it), the flow passage is completely (especially fluidly) closed and / or sealed by the throttle body and the seal. Preferably, the throttle body and the seal are in contact during all or part of the vibratory motion. Preferably, the seal is an elastic seal and / or an elastomeric seal, which allows the throttle body to perform vibratory motion while in contact with the seal. Preferably, the seal is located at a throttle body seat, which serves as a valve seat for the throttle body in the closed position. Preferably, the contact between the throttle body and the seal is physical (i.e., contact-type); preferably, the throttle body applies surface pressure to the seal during contact. Further, preferably, the contact between the throttle body and the seal is periodically interrupted during vibratory motion, thereby facilitating the drainage of water accumulated on the throttle body.

[0033] Typically, preferably, the vibrational movement is limited to at most 1%, 2%, 5%, 10%, or 20% of the maximum available travel or rotational travel of the throttle valve between the closed and open positions. For a throttle valve actuator, a throttle valve actuator with a throttle valve is provided, which is configured to perform the steps of the method. This provides a highly efficient and cost-effective throttle valve actuator. Preferably, the throttle valve actuator further includes further components configured to perform the steps of the method; for example, the throttle valve actuator or its motor can be operated by means of a control unit. Furthermore, preferably, a fuel cell system with the throttle valve actuator is provided; even more preferably, a vehicle, particularly a motor vehicle, is provided with the throttle valve actuator or the fuel cell system. Preferably, the vehicle is an electrically driven vehicle, and its electric drive can be powered by the fuel cell system.

[0034] For the aforementioned computer program, a computer program containing instructions is provided that cause the throttle actuator to perform the method. This computer program can, for example, be executed by a control unit or the control unit of the throttle actuator.

[0035] In view of the aforementioned computer-readable medium, a computer-readable medium storing the computer program is provided; preferably, the computer program is stored in non-volatile memory; more preferably, the computer program is stored on a storage medium of a throttle actuator control unit.

[0036] Advantageous improvements of the invention are set forth in the dependent claims and in the following description of the drawings. Attached Figure Description

[0037] The present invention will now be explained in detail using exemplary embodiments with reference to the accompanying drawings. In the drawings: Figure 1 A vehicle equipped with the throttle actuator of the present invention is shown; Figure 2 The throttle actuator of the present invention is shown; and Figure 3 A flowchart of the method of the present invention is shown. Detailed Implementation

[0038] See Figure 1 The vehicle 1 includes a fuel cell system 2 and a throttle actuator 3 according to the present invention. The vehicle 1 is an electric vehicle, and its electric drive is supplied with electrical energy by the fuel cell system 2. The throttle actuator 3 can be operated by a control unit 4. The control unit 4 includes a computer-readable medium 4a as non-volatile memory, and stores a computer program 4b thereon. The computer program 4b contains instructions for causing the throttle actuator 3 to perform the method of the present invention.

[0039] See Figure 2 , from Figure 1 The throttle actuator 3 includes a flow channel 7; a throttle valve 5a, 5b, and 5c are disposed therein and can be moved by a throttle valve shaft 6. The throttle valve shaft 6 can be driven by an electric motor controlled by a control unit. The figure shows the throttle valves 5a, 5b, and 5c in different positions: throttle valve 5a (shown in dashed lines) is in its closed position and completely closes the flow channel 7; throttle valve 5b (also shown in dashed lines) is in its open position and ensures the maximum possible flow cross-sectional area of ​​the flow channel 7; throttle valve 5c is located between the open and closed positions. Furthermore, the vibration direction 8 towards the open and closed positions is shown.

[0040] See Figure 3 The method of the present invention can be used by means of Figure 1 and Figure 2 The throttle actuator of the present invention is shown to perform this action. As the first process step 9, it is first determined whether the method needs to be executed. In this embodiment, it is only performed when… Figure 1 The fuel cell system shown is in a deactivated state, and Figure 1 This method is only performed when the ambient temperature of the vehicle is below 4°C. If the above condition is met, the second process step 10 is performed, moving the throttle valve to a position between the open and closed positions. Then, the third process step 11 is performed, vibrating the throttle valve along the vibration direction. The third process step 11 can be performed multiple times, preferably at time intervals. This ensures that the fluid is removed substantially completely from the throttle valve, thus reliably preventing the throttle valve from freezing at the throttle seat. As the fourth process step 12, the throttle valve is moved to its rest position, and the method ends. Preferably, the throttle valve is moved to its rest position by the return spring of the throttle valve actuator.

[0041] It should be understood that the features of different embodiments can also be combined with each other.

[0042] Figures 1 to 3 The embodiments described herein are not limiting in any way and are only used to illustrate the concept of the invention. Explanation of reference numerals in the attached figures 1 vehicle 2. Fuel Cell System 3 Throttle actuator 4 Control Unit 4a Computer-readable media 4b Computer Program 5a–5c Throttle body 6 Throttle body shaft 7. Flow channel 8. Vibration direction 9. First process step 10 Second process step 11 Third process step 12. Fourth process step

Claims

1. A method for preventing throttle actuator (3) from malfunctioning in fuel cell system (2), in, The throttle actuator (3) includes a throttle valve (5a, 5b, 5c) that is movable between an open position and a closed position. The method includes the following steps: • Vibrational motion is performed through the throttle valves (5a, 5b, 5c).

2. The method according to claim 1, Its features are, The method is performed when or after the fuel cell system (2) is shut down.

3. The method according to any of the preceding claims, Its features are, The method is initialized after a period of time following the shutdown of the fuel cell system (2).

4. The method according to any of the preceding claims, Its features are, The method is initialized based on the ambient temperature of the throttle actuator (3) or the fuel cell system (2), or the vehicle (1) including the throttle actuator (3) or the fuel cell system (2).

5. The method according to any of the preceding claims, Its features are, The vibration motion includes at least one movement that moves the throttle valves (5a, 5b, 5c) toward the open position, and at least one movement that moves the throttle valves (5a, 5b, 5c) toward the closed position.

6. The method according to any of the preceding claims, Its features are, The vibration motion is generated by the electric drive of the throttle actuator (3) and / or the return spring of the throttle actuator (3).

7. The method according to any of the preceding claims, Its features are, The method is executed multiple times consecutively, with time intervals between each execution.

8. The method according to any of the preceding claims, Its features are, The vibration motion includes the impact motion of the throttle valves (5a, 5b, 5c) on the mechanical limiters of the throttle valves (5a, 5b, 5c).

9. The method according to any of the preceding claims, Its features are, The vibration motion includes the maximum acceleration of the throttle valve (5a, 5b, 5c), which is selected such that the throttle valve actuator (3) can prevent mechanical damage caused by performing the method.

10. The method according to any of the preceding claims, Its features are, During the vibration, the throttle valves (5a, 5b, 5c) come into contact with the seals.

11. A throttle actuator (3) with throttle valves (5a, 5b, 5c). in, The throttle actuator (3) is configured to perform the steps of the method according to any of the preceding claims.

12. A computer program (4b) comprising: Instructions that enable the apparatus of claim 11 to perform the method steps of any one of claims 1 to 10.

13. A computer-readable medium (4a) having a computer program according to claim 12 stored thereon.

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