WO2018197526A1

WO2018197526A1 - Method for diagnosing clutch stuck and apparatus thereof

Info

Publication number: WO2018197526A1
Application number: PCT/EP2018/060527
Authority: WO
Inventors: HyeonDeok SEO
Original assignee: Continental Automotive Gmbh
Priority date: 2017-04-26
Filing date: 2018-04-25
Publication date: 2018-11-01
Also published as: KR101824675B1

Abstract

The present invention relates to a method and apparatus for diagnosing clutch stuck. The method for diagnosing clutch stuck is <b>characterized by</b> including steps of allowing a control unit (30) to drive a clutch actuating motor (20) so as to locate the clutch (10) within a set range for engaging the clutch (10) that interrupts power supplied from an engine to a transmission, allowing the control unit (30) to feedback operating current of the driven clutch actuating motor (20), and allowing the control unit (30) to determine that the stuck occurs in the clutch (10) when a magnitude of the fedback operating current is less than a preset reference value as a case in which the clutch (10) is located in the set range.

Description

METHOD FOR DIAGNOSING CLUTCH STUCK AND APPARATUS THEREOF Field of invention

The present invention relates to a clutch stuck diagnosis method and apparatus, and more particularly, to a clutch stuck diagnosis method and apparatus for diagnosing clutch stuck by which an operation of a clutch mounted on a transmission is not controlled.

Background of invention

A transmission means a device mounted on a vehicle and the like to generate an appropriate rotational speed and torque through a torque generating means such as an engine or a motor. Such a transmission may be represented by a manual transmission in which shifting is performed according to a manual operation of a driver and an automatic transmission in which shifting is automatically performed according to a vehicle speed or an engine load. Currently automatic transmission is being widely used.

As one of these automatic transmissions, a double clutch transmission (DCT) provided with two power transmission clutches has been developed. The double clutch transmission selectively transmits rotational force input from an engine to two input sides by using two clutches and performs shifting while alternately the two clutches on the basis of a structure in which an output is realized after the shifting is performed using rotational force of gears disposed on the two input sides. Thus, there is an advantage that torque interruption hardly occurs even during the shifting .

On the other hand, in such an automatic transmission, there may occur a problem of Clutch stuck' by which the clutch mounted therein is fixed in an engaged state, and thus an operation of the transmission is not controlled. For example, when a rotational speed of a transmission input shaft is detected as a value similar to that of a rotational speed of the engine although the clutch is in a fully dis-engaged state such as when the vehicle is in an idle state, there is a possibility that the clutch is in a stuck state, and when the idle state of the vehicle is released, and the gears are engaged in the stuck state of the clutch, there is a possibility of causing a serious accident due to sudden driving of the vehicle.

In addition, conventionally, there is a problem that only the post-operation with respect to the clutch stuck is possible because the stuck state of the clutch is determined only after the starting of the engine.

The background art of the present invention is disclosed in Korean Patent Publication No. 10-2010-0089221 (published on August 12, 2010) . Description

The present invention has been made to solve the above-mentioned problems, and an object according to one aspect of the present invention is to provide a method and apparatus for diagnosing clutch stuck, through which the stuck of the clutch mounted on a transmission is diagnosed to prevent an accident from occurring, and the clutch stuck is diagnosed before starting of an engine as well as after the starting of the engine to prevent possibility of occurrence of the accident. A method for diagnosing clutch stuck according to one aspect of the present invention is characterized by including steps of allowing a control unit to drive a clutch actuating motor so as to locate the clutch within a set range for engaging the clutch that interrupts power supplied from an engine to a transmission, allowing the control unit to feedback operating current of the driven clutch actuating motor, and allowing the control unit to determine that the stuck occurs in the clutch when a magnitude of the fed back operating current is less than a preset reference value as a case in which the clutch is located in the set range.

In the present invention, the reference value may be a magnitude of the operating current of the clutch actuating motor, which is required for locating the clutch within the set range in a normal state in which the sticking does not occur in the clutch.

An apparatus for diagnosing clutch stuck according to one aspect of the present invention is characterized by including: a clutch interrupting power supplied from an engine to a transmission; a clutch actuating motor controlling engagement and dis-engagement of the clutch; and a control unit driving the clutch actuating motor so as to locate the clutch within a set range for engaging the clutch, feeding back an operation current of the driven clutch actuating motor, and determining that the stuck occurs in the clutch when a magnitude of the fed back operating current is less than a preset reference value as a case in which the clutch is located in the set range.

In the present invention, the reference value may be a magnitude of the operating current of the clutch actuating motor, which is required for locating the clutch within the set range in a normal state in which the stuck does not occur in the clutch.

In the present invention, the clutch may be a dual clutch mounted on a dual clutch transmission (DCT) .

According to the one aspect of the present invention, the stuck state of the clutch may be diagnosed early to prevent the accident due to the clutch stuck from occurring, and only the stuck diagnosis logic which feeds back the operating current of the clutch actuating motor without a separate additional component for diagnosing the clutch stuck to diagnose the clutch stuck may be applied to more economically and effectively diagnose the clutch stuck.

FIG. 1 is a block diagram for explaining an apparatus for diagnosing clutch stuck according to an embodiment of the present invention . FIGS. 2 and 3 views for explaining clutching engaging and dis-engaging operation in the apparatus for diagnosing the clutch stuck according to an embodiment of the present invention. FIG. 4 is a flowchart for explaining the apparatus for diagnosing the clutch stuck according to an embodiment of the present invention .

FIG. 5 is a view illustrating a relationship between a position of the clutch and the operating current of the clutch actuating motor in the apparatus for diagnosing the clutch stuck according to an embodiment of the present invention.

Hereinafter, an embodiment of a method and apparatus for di- agnosing clutch stuck according to the present invention will be described with reference to the accompanying drawings. In the description, the thickness of lines or the size of components shown in the drawings may be exaggerated for the clarity and convenience of the description. In addition, the following terms are defined in consideration of functions in the present invention, and the definitions thereof may vary depending on the intention or practice of users or operators. Thus, definitions of the terms should be made based on the contents throughout this specification .

FIG. 1 is a block diagram for explaining an apparatus for diagnosing clutch stuck according to an embodiment of the present invention, and FIGS. 2 and 3 are views for explaining clutching engaging and dis-engaging operation in the apparatus for di- agnosing the clutch stuck according to an embodiment of the present invention.

Referring to FIGS. 1 to 3, an apparatus for diagnosing clutch stuck according to an embodiment of the present invention may include a clutch (10), a clutch actuating motor (20), and a control unit (30) . The clutch (10) may include a pressing member (11), an elastic member (13), a pressure plate (15), a clutch disk (17) , and a flywheel (19) . In this embodiment, although a dual clutch mounted on a dual clutch transmission is described as an example of the clutch (10) as illustrated in FIGS. 2 and 3, the present invention is not limited thereto and may be applied to various clutches such as an automatic transmission and a continuously variable transmission .

The clutch (10) may interrupt power supplied from an engine to a transmission. For this, as illustrated in FIGS. 2 and 3, the clutch (10) may include the pressing member (11), the elastic member (13), the pressure plate (15), the clutch disk (17) and the flywheel (19) . The pressing member (11) may be implemented by a release bearing or a thrust bearing, and the elastic member (13) may be implemented by a diaphragm spring, but they are not limited thereto.

The clutch actuating motor (20) may control engagement and dis-engagement of the clutch (10) controlled by the control unit (30) that will be described later, and the control unit (30) may control driving of the clutch actuating motor (20) through a separate motor driving driver (not shown) . The clutch actuating motor (20) may be designed to have a structure which is mechanically connected to the pressing member (11) through a screw shaft and a screw nut. Thus, a rotational motion of the clutch actuating motor (20) may be converted into a linear motion to press the pressing member (11) .

The engaging and dis-engaging operations of the clutch (10) will be briefly described based on the above-described configurations of the clutch (10) and the clutch actuating motor (20) with reference to FIGS. 2 and 3.

FIG. 2 illustrates a state in which the clutch actuating motor (20) is turned off to dis-engage the clutch (10) . When the control unit (30) drives the clutch actuating motor (20), the rotational motion of the clutch actuating motor (20) may be converted into the linear motion through the screw shaft and the screw nut to press the pressing member (11), and the elastic member (13) and the pressing plate (15) may be pressed by the pressing member (11) in one direction to engage the clutch disk (17) with the flywheel

(19) so that the clutch (10) is engaged. FIG. 3 illustrates a state in which the clutch actuating motor (20) is driven to engage the clutch (10) . This embodiment is characterized in that the stuck of the clutch (10) is diagnosed based on the operating current of the clutch actuating motor (20) , which is required for locating the clutch (10) within a set range by pressing the pressing member (11) and the elastic member (13), and a detailed description thereof will be described later.

When the control unit (30) turns off the clutch actuating motor

(20) , the elastic member (13) returns to its original state by the elastic force thereof to space the clutch disk (17) apart from the flywheel (19), thereby dis-engaging the clutch (10) .

In this embodiment, although the dual clutch transmission is described as an example in which the clutch (10) is engaged when the clutch actuating actuating motor (20) is driven, and the clutch (10) is dis-engaged when the clutch actuating motor (20) is turned off, in some embodiments, the engagement and dis-engagement of the clutch (20) due to the operation of the clutch actuating motor (20) are implemented to be performed in reverse to the operations according to this embodiment.

This embodiment is characterized in that the stuck of the clutch (10), which may occur during a normal operation of the above-described clutch (10), is diagnosed. Hereinafter, the configuration for diagnosing the stuck of the clutch (10) will be described in detail with reference to the operation of the control unit (30) .

The control unit (30) may drive the clutch actuating motor (20) to locate the clutch (10) within the set range for engaging the clutch (10) and feedback the operating current of the driven clutch actuating motor (20), and then, when a magnitude of the fed back operating current is less than a preset reference value as a case in which the clutch (10) is located in the set range, it may be determined that the sticking occurs in the clutch (10) .

Here, the reference value means the magnitude of the operating current of the clutch actuating motor (20) , which is required for locating the clutch (10) within the set range in the normal state in which the stuck does not occur in the clutch (10) , and may be variously designed based on experimental results and previously set in the control unit (30) .

Hereinafter, a process of diagnosing the stuck of the clutch (10) by the control unit (30) will be described with reference to FIGS . 4 and 5. FIG. 4 is a flowchart for explaining the apparatus for diagnosing the clutch stuck according to an embodiment of the present invention, and FIG. 5 is a view illustrating a relationship between a position of the clutch and the operating current of the clutch actuating motor in the apparatus for diagnosing the clutch stuck according to an embodiment of the present invention.

Explaining the method for diagnosing the clutch stuck according to an embodiment of the present invention with reference to FIG. 4, first, the control unit (30) drives the clutch actuating motor (20) to locate the clutch (10) within the set range for engaging the clutch (10) (S10) . Here, the set range means a target position for locating the clutch (10) to diagnose the stuck of the clutch (10) , may be variously designed based on the experimental results and previously set in the control unit (30), and be implemented as an embodiment in which a specific critical value is previously set to locate the clutch (10) at a position that is above the specific critical value.

Then, the control unit (30) feeds back the operating current of the driven clutch actuating motor (20) (S20) .

Then, when the magnitude of the operating current, which is fed back in the step S20 in the control unit (30), is less than the previously set reference value (S30) as in the case in which the clutch (10) is located in the set range, the control unit (30) determines that the stuck occurs in the clutch (10) (S40), in other cases, the control unit determines that the clutch (10) is in the normal state (S50) . The reference value means the magnitude of the operating current of the clutch actuating motor (20) , which is required for locating the clutch (10) within the set range in the normal state in which the stuck does not occur in the clutch (10) , and may be variously designed based on experimental results and previously set in the control unit (30) .

Particularly, when the clutch (10) is in the normal state, since reaction force of the elastic member (13) increases as the target position for engaging the clutch (10) increases (Hook' s low) , the target position for engaging the clutch (10) and the magnitude of the operating current of the clutch actuating motor (20) are proportional to each other as illustrated in FIG. 5. On the other hand, when the clutch (10) is in the stuck state, the reaction force of the elastic member (13) does not affect the operating current of the clutch actuating motor (20) . Thus, since the clutch actuating motor (20) driven in the steps S10 and S20 is driven in a state beyond an external load, i.e., the reaction force of the elastic member (13), the operating current has a value less than that of the operating current of the clutch actuating motor (20) in the normal state in which the reaction force of the elastic member (13) is applied.

Thus, in this embodiment, the magnitude of the operating current of the clutch actuating motor (20) which is required for locating the clutch (10) within the set range is previously set as the reference value, and the operating current is fed back from the clutch actuating motor (20) while the clutch (10) is located in the set range. Then, when the magnitude is less than the reference value, since it is determined that the clutch actuating motor (20) is operating without receiving the reaction force of the elastic member (13), it may be determined that the stuck occurs in the clutch (10) . When it is determined that the stuck occurs in the clutch (10), the control unit (30) according to this embodiment may audibly warn the driver that the clutch (10) needs to be repaired through a display or a speaker on a cluster unit.

As described above, the clutch (10) according to this embodiment may be implemented as the dual clutch mounted on the dual clutch transmission. Thus, the method for diagnosing the clutch stuck according to this embodiment may be applied to diagnose the stuck on all the clutch that is in the engaged state and the clutch that is in the dis-engaged state.

Also, in the method for diagnosing the clutch stuck according to this embodiment, the stuck of the clutch (10) may be diagnosed in the manner using the operating current of the clutch actuating motor (20) regardless of whether the engine is turned on and off, and thus, the stuck state of the clutch (10) may be detected not only after the engine start but also before the engine start. As described above, in this embodiment, the stuck state of the clutch may be diagnosed early to previously prevent the accident due to the clutch stuck from occurring, and only the stuck diagnosis logic which feedbacks the operating current of the clutch actuating motor without a separate additional component for diagnosing the clutch stuck to diagnose the clutch stuck may be applied to more economically and effectively diagnose the clutch stuck.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims . Therefore, the technical protection scope of the present invention should be defined by the following claims .

10: Clutch 11: Pressing member

13: Elastic member

15: Pressing plate

17: Clutch disk

19: Flywheel

20: Clutch actuating motor

30: Control unit

Claims

Patent claims

1. A method for diagnosing clutch stuck, characterized by

comprising steps of: allowing a control unit to drive a clutch actuating motor so as to locate the clutch within a set range for engaging the clutch that interrupts power supplied from an engine to a transmission; allowing the control unit to feedback operating current of the driven clutch actuating motor; and allowing the control unit to determine that the stuck occurs in the clutch when a magnitude of the fed back operating current is less than a preset reference value as a case in which the clutch is located in the set range.

The method for diagnosing clutch stuck of claim 1, wherein the reference value means a magnitude of the operating current of the clutch actuating motor, which is required for locating the clutch within the set range in the normal state in which the stuck of the clutch does not occur.

3. An apparatus for diagnosing clutch stuck, characterized by comprising :

a clutch interrupting power supplied from an engine to a transmission; a clutch actuating motor controlling engagement and dis-engagement of the clutch; and a control unit driving the clutch actuating motor so as to locate the clutch within a set range for engaging the clutch, feeding back an operation current of the driven clutch actuating motor, and determining that the stuck occurs in the clutch when a magnitude of the fed back operating current is less than a preset reference value as a case in which the clutch is located in the set range.

4. The apparatus for diagnosing clutch stuck of claim 3, wherein the reference value means a magnitude of the operating current of the clutch actuating motor, which is required for locating the clutch within the set range in the normal state in which the stuck of the clutch does not occur.

5. The input circuit of claim 3, wherein the clutch is a dual clutch mounted on a dual clutch transmission (DCT) .