CN110513473B

CN110513473B - Method and device for diagnosing shift fork of transmission moving at neutral position

Info

Publication number: CN110513473B
Application number: CN201810492039.8A
Authority: CN
Inventors: 冯国雨; 张蕾; K·施奈德尔
Original assignee: Vitesco Technologies Holding China Co Ltd
Current assignee: Vitesco Technologies Holding China Co Ltd
Priority date: 2018-05-22
Filing date: 2018-05-22
Publication date: 2021-10-29
Anticipated expiration: 2038-05-22
Also published as: CN110513473A

Abstract

The invention discloses a diagnosis method and a diagnosis device for movement of a transmission shifting fork at a neutral position, wherein the method comprises the following steps: starting a timer in response to detecting that the shift fork returns to a neutral position; in response to expiration of the timer, determining that the shift fork is not in the neutral position; and triggering the shifting fork to move to the neutral position to cause a fault.

Description

Method and device for diagnosing shift fork of transmission moving at neutral position

Technical Field

The invention relates to the field of automobiles, in particular to a diagnosis method and a diagnosis device for movement of a transmission shifting fork at a neutral position.

Background

The dual clutch transmission is based on two clutches and a fork shifter to achieve automatic shifting. The double-clutch transmission has the characteristics of high-efficiency transmission efficiency and comfortableness, and can realize uninterrupted power output. A dual-clutch transmission relates to a mechanical, electrical and hydraulic integrated control technology. Through data input of an accelerator pedal, a vehicle speed sensor and other control modules, a Transmission Control Unit (TCU) calculates a target gear, and a hydraulic control system (HCU) establishes a corresponding oil pressure passage by controlling a corresponding electromagnetic valve, so that a shifting fork is pushed to achieve the purpose of engaging the gear.

The shifting fork position is obtained by a shifting fork position sensor in the double-clutch transmission, so that the success or failure of gear engagement is judged. The shift fork position sensor detects the position of the shift fork, and the transmission control unit controls the gearbox according to the current shift fork position. Accurate fork position is critical to control of the transmission. Due to reasons such as mechanical failure, the situation that the shifting fork moves from the neutral position when the transmission does not send a gear shifting command can occur, and the transmission fails to shift gears. A similar situation occurs in other types of transmissions that use shift forks to effect gear shifting, such as AMT.

It can be seen that there is a need in the art for a solution for diagnosing movement of a transmission fork in a neutral position.

Disclosure of Invention

In one aspect of the present invention, there is provided a diagnostic method of a transmission fork moving in a neutral position when a shift command is not received, comprising: starting a timer in response to detecting that the shift fork returns to a neutral position; in response to expiration of the timer, determining that the shift fork is not in the neutral position; and triggering the shifting fork to move to the neutral position to cause a fault.

In another aspect of the present invention, there is provided a diagnostic device for a transmission fork to move in a neutral position when a shift command is not received, including: a fork position detection module configured to detect whether the fork returns to a neutral position; a timer module configured to start a timer in response to detecting that the shift fork is returned to the neutral position; the shift fork position detection module is further configured to determine that the shift fork is in a neutral position in response to expiration of a timer; and a fault triggering module configured to trigger the shift fork to move the fault at the neutral position.

According to the diagnosis solution for the shifting fork of the transmission to move at the neutral position when the shifting command is not received, the fault of the shifting fork of the transmission to move at the neutral position when the shifting command is not received can be effectively diagnosed and processed, and the occurrence of error diagnosis is reduced or eliminated, so that the driving safety is improved.

Drawings

FIG. 1 illustrates a diagnostic method of a transmission fork moving in a neutral position when no shift command is received according to an embodiment of the present invention; and

fig. 2 shows a diagnostic device in which a transmission fork is moved in a neutral position when no shift command is received according to an embodiment of the present invention.

Detailed Description

Embodiments of the present invention are described below with reference to the drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of, and enabling description for, those skilled in the art. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. Furthermore, it should be understood that the invention is not limited to the specific embodiments described. Rather, any combination of the features and elements described below is contemplated as carrying out the invention, whether or not they relate to different embodiments. Thus, the following aspects, features, embodiments and advantages are merely illustrative and are not considered elements or limitations of the claims except where explicitly recited in a claim.

Referring now to FIG. 1, a diagnostic method of a transmission fork moving in a neutral position when no shift command is received is shown according to an embodiment of the present invention. The method may be performed, for example, by a Transmission Control Unit (TCU). As is known in the art, a TCU is a device used in modern vehicles for controlling a transmission that uses signals from sensors such as vehicle speed, accelerator pedal, and the like, as well as signals from an Engine Control Unit (ECU) and the like to calculate how and when to shift for the vehicle to achieve optimal performance, fuel economy, and shift quality. A TCU typically includes a processor, memory, signal processing circuitry, a power driver module, and the like. The memory stores software code specifying functions and operations to be performed by the TCU, and the processor performs the functions of the TCU by loading and executing the software code. Thus, a diagnostic method of transmission fork movement in a neutral position according to an embodiment of the present invention may be embodied in the software code, for example, and executed by the processor by loading and executing the software code.

As shown in fig. 1, the diagnostic method of the transmission fork moving in the neutral position when no shift command is received according to the embodiment of the present invention includes the steps of:

in step 101, a timer is started in response to detecting that the shift fork is returned to the neutral position. In some exemplary embodiments, a fork position sensor may be used to detect whether the fork is returned to a neutral position. The fork position sensor may be configured to, for example, continuously (e.g., every 10 milliseconds) detect fork position and communicate the detected fork position to the TCU. The TCU can judge whether the shifting fork returns to the neutral position or not (namely, the shifting fork returns to the neutral position from the gear engaging position) by comparing the received shifting fork position with the previously received shifting fork position after receiving the shifting fork position from the shifting fork position sensor, and starts a timer when judging that the shifting fork returns to the neutral position.

The timer may be implemented in TCU software, for example. In some exemplary embodiments, the timer may be a countdown timer having a preset count length. The timer length may be set, for example, typically to 50-100 milliseconds and may be adjusted, for example, by the TCU or by the user based on default values, oil temperature, experience with the use, etc. Through providing countdown timer sets up certain timing length, can get back to the shift fork and take into account owing to the short-term fluctuation that causes such as machinery, hydraulic pressure behind the neutral position to can not just get back to the shift fork short-term fluctuation after the neutral position false alarm for the shift fork removes the trouble at the neutral position. It can be seen that the timing length can be set and adjusted to be slightly greater than the expected surge time after the shift fork is returned to the neutral position, which can be done simply by the TCU or by the user based on defaults, oil temperature, experience with the user, etc., and the present invention is not limited thereto.

In step 102, it is determined whether the timer has expired, i.e., the timer length has been reached after the timer is started. This step may be performed by the TCU, for example.

In step 103, it is determined whether the shift fork is in the neutral position in response to expiration of the timer. In some exemplary embodiments, a fork position sensor may be used to determine whether the fork is in a neutral position. For example, the TCU may determine whether the fork is in the neutral position based on the current fork position received from the fork position sensor when the timer expires.

In step 104, a fault counter is incremented in response to determining that the shift fork is not in the neutral position. For example, the TCU may increment the fault counter by 1 upon determining that the current fork position does not belong to the neutral position (e.g., the fork has moved from the neutral position). The failure counter may be implemented in TCU software, for example. The failure counter may be initially set to zero after the vehicle is shipped or repaired, for example, and may return to zero after the trigger fork moves the failure in the neutral position and the failure is addressed.

Accordingly, if it is judged that the shift fork is in the neutral position, the failure counter is not incremented but returned to before step 101 to continuously detect whether the shift fork is returned to the neutral position, and in step 101, in response to the detection that the shift fork is returned to the neutral position, a timer is started to start the next cycle.

At step 105, it is determined whether the fault counter has reached a threshold. This step may be performed by the TCU, for example.

The threshold may be set, for example, generally between 3-10. The threshold may be initially set in the TCU, for example. In some further exemplary embodiments, the threshold may be adjusted accordingly by the TCU or by the user based on initial values, transmission conditions, experience with the use, and the like. The TCU or the user may adjust the threshold in any manner known to those skilled in the art, and the present invention is not limited in this regard.

In some exemplary embodiments, the threshold may be set to 1, and in this case, whenever it is determined in step 103 that the shift fork is not in the neutral position, the fault counter reaches the threshold, thereby triggering the shift fork to move the fault in the neutral position. In fact, in such an embodiment, the failure counter and the

steps

104 and 105 may be eliminated, and the step 106 of triggering the shift fork to move to the neutral position may be directly executed when the shift fork is judged not to be in the neutral position in the step 103.

By using the fault counter, the occurrence of the fault of the movement of the false alarm shifting fork at the neutral position can be further reduced. The shift fork may be accidentally moved in the neutral position for mechanical reasons and the like. The accidental shifting forks can be automatically repaired without being processed when moving at the neutral position; only those recurring shifts in the neutral position are faults that need to be dealt with. It is for this reason that the fault counter and its threshold are set.

In step 106, in response to determining that the fault counter has reached the threshold, the shift fork is triggered to move the fault in the neutral position. For example, the TCU may determine whether the failure counter reaches a predetermined threshold value after the failure counter is incremented by 1, and trigger the shift fork to move to the neutral position to fail when the failure counter reaches the threshold value.

In some exemplary embodiments, the triggering fork moving failure in the neutral position includes: the vehicle is put into a functional safety mode including shaft or gear disabling. The shaft prohibition for example includes prohibiting the shaft on which the failed shift fork is located from participating in the subsequent shift operation, and the gear prohibition for example includes prohibiting the failed shift fork from participating in the subsequent shift operation. This step may be performed by the TCU, for example.

In other exemplary embodiments, the failure of the trigger fork to move in the neutral position may further include other failure handling means, such as alarming a user, stopping the vehicle from running, and the like.

In some exemplary embodiments, the transmission is a dual clutch transmission.

The diagnostic method of the transmission fork moving in the neutral position when no shift command is received according to the embodiment of the present invention is described above with reference to the accompanying drawings, and it should be noted that the above description is only an example and not a limitation of the present invention. In other embodiments of the invention, the method may have more, fewer, or different steps, and the order, inclusion, or functional relationship between the steps may be different from that described and illustrated. For example, in general, multiple steps may be combined into a single step, a single step may be split into multiple steps, and so on.

In another aspect of the present invention, a diagnostic device is also provided for movement of a transmission fork in a neutral position when no shift command is received.

Fig. 2 shows a diagnostic device 200 for a transmission fork according to an embodiment of the invention moving in a neutral position when no gear shift command is received. In some exemplary embodiments, the device 200 is implemented by a Transmission Control Unit (TCU). That is, the functions of the modules in the apparatus 200 may be specified by software code stored in the memory of the TCU, which when loaded and executed by the processor of the TCU, performs the functions of the modules in the apparatus 200 to thereby constitute the modules in the apparatus 200. Further, functions or operations of the respective modules in the device 200 correspond to the respective steps in the above-described diagnostic method for the shift fork of the transmission according to the embodiment of the present invention to be moved in the neutral position, and parts of details overlapping with the above description are omitted in the following description for the sake of brevity, so that a more detailed understanding of the device 200 can be obtained with reference to the above description.

As shown in fig. 2, the diagnostic apparatus 200 for a transmission fork to move in a neutral position when a shift command is not received according to an embodiment of the present invention includes the following modules:

a fork position detection module 201 configured to detect whether the fork returns to a neutral position;

a timer module 202 configured to start a timer in response to detecting that the shift fork is returned to the neutral position;

the fork position detection module 202 is further configured to determine that the fork is in a neutral position in response to expiration of a timer; and

and a fault triggering module 203 configured to trigger the shift fork to move to a neutral position to cause a fault.

In some exemplary embodiments, the apparatus 200 further comprises:

a fault counter module 204 configured to increment a fault counter in response to determining that the shift fork is not in the neutral position;

and wherein the fault triggering module 204 is further configured to determine whether a fault counter has reached a threshold, and the triggering the shift fork to move the fault in the neutral position is performed in response to determining that the fault counter has reached the threshold.

In some exemplary embodiments, the fork position detection module 201 uses a fork position sensor to detect whether the fork returns to a neutral position and to determine whether the fork is in the neutral position.

In some exemplary embodiments, the fault triggering module 203 configured to trigger the shift fork to move the fault in the neutral position includes:

the false trigger module 203 is configured to put the vehicle into a functional safety mode that includes shaft or gear deactivation.

In some exemplary embodiments, the transmission is a dual clutch transmission.

The diagnostic apparatus for moving the transmission fork in the neutral position when no shift command is received according to the embodiment of the present invention is described above with reference to the accompanying drawings, and it should be noted that the above description is only an example and not a limitation of the present invention. In other embodiments of the present invention, the diagnostic device in which the transmission fork is moved in the neutral position may have more, fewer, or different components, and the connections, inclusions, functions, etc. between the components may be different from those described. For example, generally, the functions performed by one module may be performed by another module, multiple modules may be combined into one larger module, or one module may be split into multiple modules, and so on.

The foregoing description of the embodiments of the present invention has been presented for purposes of illustration and description, and numerous specific details are set forth, such as examples of specific components and devices, in order to provide a thorough understanding of the embodiments of the present invention, which are not intended to be exhaustive or limiting of the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in other embodiments, even if not specifically shown or described. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the present invention. In some example embodiments, well-known components, structures, and well-known techniques have not been described in detail.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. The names of the various components in this application are intended to be descriptive only and not as limitations of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having," are inclusive and therefore specify the presence of stated features, entities, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, entities, steps, operations, elements, components, and/or groups thereof. The steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless an order of performance is explicitly stated.

When an element is referred to as being "on," "engaged to," "connected to" or "coupled to" another element, it can be directly on, engaged, connected or coupled to the other element or intervening elements may be present. Other words used to describe the relationship between elements should be interpreted in a similar manner (e.g., "between" and "directly between," "adjacent" and "directly adjacent," etc.). As used herein, "connected," "coupled," or similar terms, may refer to any one or more of a mechanical coupling, an electrical coupling, a communication coupling, without further explicit limitation. Further, as used herein, the term "and/or", "and/or" includes any and all combinations of one or more of the associated listed items.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art will appreciate that the above description is by way of example only, and not by way of limitation. Various modifications and variations may be made to the embodiments of the present invention while remaining within the spirit and scope of the invention, which is to be determined only by the following claims.

Claims

1. A diagnostic method for a transmission fork to move in a neutral position when no shift command is received, comprising:

starting a timer in response to detecting that the shift fork returns to a neutral position;

in response to expiration of the timer, determining that the shift fork is not in the neutral position;

responding to the judgment that the shifting fork is not in the neutral position, and incrementing a fault counter;

judging whether the fault counter reaches a threshold value; and

in response to the fault counter reaching a threshold, the shift fork is triggered to move the fault in the neutral position.

2. The method of claim 1, wherein a fork position sensor is used to detect whether the fork is returned to a neutral position and to determine whether the fork is in the neutral position.

3. The method of claim 1, wherein the activating fork moving fault in a neutral position comprises:

the vehicle is put into a functional safety mode including shaft or gear disabling.

4. The method of claim 1, wherein the method is performed by a transmission control unit.

5. A diagnostic device for a transmission fork to move in a neutral position when no shift command is received, comprising:

a fork position detection module configured to detect whether the fork returns to a neutral position;

a timer module configured to start a timer in response to detecting that the shift fork is returned to the neutral position;

the shift fork position detection module is further configured to determine that the shift fork is in a neutral position in response to expiration of a timer;

a fault counter module configured to increment a fault counter in response to determining that the shift fork is not in the neutral position, and determining whether the fault counter reaches a threshold; and

a fault triggering module configured to trigger the shift fork to move the fault in the neutral position in response to determining that the fault counter reaches a threshold.

6. The apparatus of claim 5, wherein the fork position detection module detects whether the fork is returned to the neutral position and determines whether the fork is in the neutral position using a fork position sensor.

7. The apparatus of claim 5, wherein the fault triggering module configured to trigger the shift fork to move the fault in the neutral position comprises:

the fail-over module is configured to cause the vehicle to enter a functional safety mode including shaft or gear deactivation.

8. The apparatus of claim 5, wherein the apparatus is implemented by a transmission control unit.