WO2006001625A1

WO2006001625A1 - Semi auto clutch driving apparatus and driving method

Info

Publication number: WO2006001625A1
Application number: PCT/KR2005/001911
Authority: WO
Inventors: Jang-Soo Kim
Original assignee: Jeonju Machinery Research Center
Priority date: 2004-06-28
Filing date: 2005-06-21
Publication date: 2006-01-05
Also published as: KR100586774B1; KR20060000265A

Abstract

A semi auto clutch driving apparatus and a driving method using the same is provided. The apparatus is capable of freely shifting gears without the use of a clutch by easily engaging and disengaging engine power to and from the transmission of a vehicle through depressing a brake pedal or using an on/off clutch switch mounted on a gear shifter. The apparatus includes a forward button, a half-clutch button, a reverse button, a low speed mode button, an engine rpm sensor, a brake sensor, a pushrod position sensor that determines the position of a pushrod by sensing the rotation of a motor, a motor that engages and disengages a clutch disc by powering the pushrod back and forth, a motor speed control volume, a pushrod parameter setting volume, a half-clutch setting volume, a controller that controls an output portion according to inputted data in an input portion, and an engine rev booster that increases engine rpms by opening the engine throttle valve. In order to accurately gauge the point that the clutch disc should be engaged under varying driving conditions and according to engine output values, engine rpm data is used as the basis for determining the clutch disc engagement point. By engaging the clutch disc by only as much as a value of engine rpm increase, engine power can be smoothly transferred to the transmission.

Description

SEMI AUTO CLUTCH DRIVING APPARATUS AND DRIVING

METHOD

Technical Field [1] The present invention relates to a semi auto clutch driving apparatus of a vehicle, and more specifically, to a semi auto clutch driving apparatus capable of appropriately engaging a clutch disc to a flywheel at changing engine output values (rpms, etc.), according to different driving conditions of the vehicle, and a driving method for the driving apparatus. Background Art [2] In a manual clutch apparatus, depressing a clutch pedal activates a master cylinder, which in turn activates a release cylinder. The movement of the release cylinder, in conjunction with a pressure plate, engages and disengages a clutch disc to and from a flywheel, so that driving force from an engine can be disengageably relayed to a transmission. [3] However, because a driver must depress a clutch pedal to change gears in a manual transmission, city driving or driving in heavy traffic results in fatigue. [4] Automatic transmissions, designed to overcome the problems of manual transmissions, make driving easier and provide a smoother ride; however, automatic transmissions involve higher purchasing costs and a 20 - 30% increase in fuel consumption when compared to manual transmissions. [5] Semi auto clutches were designed to provide the benefits of both manual and automatic transmissions, by dispensing with the clutch pedal and switching gears by employing brake pedal activation or a clutch on/off switch on a gear shifter to con¬ veniently engage and disengage the driving force of a vehicle's engine to and from its drive wheels. Such prior art semi auto clutch apparatuses use a drive master cylinder, installed between the master cylinder and the release cylinder, for acting as the master cylinder, and various sensors installed around the engine to provide sensor values of the vehicle's operating status and activate the drive master cylinder to engage the clutch when conditions dictate its engagement. Disclosure of Invention Technical Problem [6] Such prior art semi auto clutches, however, only take into account various sensor values taken of a vehicle's operating engine, and fail to consider factors such as the vehicle moving on an incline versus a level surface or being heavily versus lightly loaded. Thus, when the clutch is engaged according to the sensor data, the clutch can be prematurely engaged, resulting in vibration or stalling caused by engine overload; or the clutch can be tardily engaged, resulting in delayed starts or increased fuel consumption. [7] Also, because the clutch is always engaged at a certain point under certain driving conditions, half-clutching is not a condition that can be prolonged, resulting in jerky starts and stalling easily. [8] An object of the present invention is to provide a semi auto clutch driving apparatus that accurately determines the point for clutch disc engagement based on varying engine output values according to driving conditions. Furthermore, in order to implement frequently occurring half-clutching that is used when driving a manual transmission, the point for clutch disc engagement is based on engine rpm data, and the amount of clutch travel for engagement is made proportional to the increase in rpms, enabling smooth transfer of engine power to the transmission and thus, smooth starts. Technical Solution [9] To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a semi auto clutch driving apparatus of the present invention includes: a forward button for rotating a motor in a forward direction to push a pushrod forward and disengaging a clutch disc; a motor for engaging and disengaging the clutch disc by using a device to transform the motor's rotational movement to a linear forward and backward movement of the pushrod; a half-clutch button for positioning the clutch disc in a half-clutch position; a reverse button for forcibly engaging the clutch disc by rotating the motor in a reverse direction; a low speed mode button for engaging and disengaging the clutch disc according to an increase or decrease in rpms; an engine rpm sensor for sensing engine speed; a brake sensor for sensing brake operation; a pushrod position sensor for sensing the position of the pushrod by sensing the rotation of the motor, on account of the device transforming the motor's rotational movement to the pushrod's linear movement; a motor speed control volume for controlling the speed of the motor; a pushrod parameter setting volume for setting a pushrod movement parameter; a half-clutch setting volume for a user to enter a setting for a half-clutch position; a controller for controlling an output portion according to data inputted in an input portion; an engine rev booster for opening a throttle valve on the engine to increase engine speed; and an indicator lamp for indicating the status of the controller. [10] The semi auto clutch apparatus of the present invention further includes: a clutch disc disengagement stage for disengaging the clutch disc by rotating the motor in a forward direction via a forward button signal; a half-clutch stage for activating the engine rev booster and driving the motor to position the clutch disc in a half-clutch position, via an input signal from the half-clutch button; and a clutch disc engagement stage for engaging the clutch disc by means of an input signal from the engine rev booster or reverse button. Advantageous Effects [11] By designating engine rpms as the basis for determining the point of clutch disc engagement, and engaging the clutch disc only by an amount proportional to an engine speed increase value, a vehicle equipped with the semi auto clutch driving apparatus of the present invention is capable of sustaining half-clutching for smoothly transferring engine power to the transmission. Because engine speed is the most accurate reflector of drivetrain loads, the present invention automatically controls clutch operation based on rpm data, in order to smoothly transfer engine power to a vehicle's transmission. Brief Description of the Drawings [12] Fig. 1 is a schematic structural view of a semi auto clutch according to an embodiment of the present invention; [13] Fig. 2 is a block diagram of a controller of the semi auto clutch of the present invention; and [14] Fig. 3 is a control flowchart of the semi auto clutch of the present invention. Best Mode for Carrying Out the Invention [15] Hereinafter, preferred embodiments of a semi auto clutch apparatus according to the present invention will be described in detail with reference to the accompanying drawings. [16] Fig. 1 is a schematic structural view of the semi auto clutch according to an embodiment of the present invention. [17] Referring to Fig. 1, the semi auto clutch system of the present invention includes: a clutch pedal Ml, a master cylinder M4, a motor 12, a pushrod gear M5, a pushrod position sensor 7, a drive master cylinder M8, a release cylinder M9, and a clutch M 12. Each cylinder M4, M8, and M9 has a pushrod M2, M6, Ml 1 and piston M3, M7, MlO, and the drive master cylinder M8 in "manual mode" simply relays force applied from the master cylinder M4 to the release cylinder M9, but acts in lieu of the master cylinder M4 through the operation of the motor 12 in "automatic mode". [18] In addition, the master cylinder M4 dispenses hydraulic pressure when the clutch pedal Ml is depressed, and the release cylinder M9 transforms the hydraulic pressure applied by the master cylinder M4 or the drive master cylinder M8 into mechanical energy to engage or disengage the clutch disc. The pushrod gear M5 transforms the rotational force of the motor 12 to a linear, back-and-forth movement so that when the pushrod M6 of the drive master cylinder M8 is pushed forward, hydraulic pressure is created. [19] Fig. 2 is a block diagram of a controller of the semi auto clutch of the present invention. The semi auto clutch driving apparatus includes a control switch portion A, a sensor portion B, a setting portion C, a controller 30, a motor 12, an engine rev booster 13, and an indicator lamp 14. The control switch portion A rotates the motor 12 in a forward or reverse direction according to preset values and values sensed by the sensor portion B, and controls the engine rev booster 13. The indicator lamp 14 indicates operation of the control switch portion A. Furthermore, the control switch portion A includes a forward button 1 for disengaging the clutch disc, a half-clutch button 2 for sustaining a half-clutch position, a reverse button 3 for engaging the clutch disc, and a low speed mode button 4. The sensor portion B includes an engine rpm sensor 5, a brake sensor 6, and a pushrod position sensor 7; and the setting portion C includes a motor speed control volume 8, a pushrod parameter setting volume 9, a half- clutch setting volume 10, and a connecting rpm setting volume 11. [20] Referring to Fig. 2, the forward button 1 pushes the pushrod M6 forward by rotating the motor 12 in a forward direction, to disengage the clutch disc. The half-clutch button 2 positions the clutch disc in a half-clutch position; the reverse button 3 rotates the motor 12 in a reverse direction, to forcibly engage the clutch disc; and the low speed mode button 4 engages and disengages the clutch disc, according to an increase or decrease in rpms. [21] The engine rpm sensor 5 senses engine speed, the brake sensor 6 senses brake operation, and the pushrod position sensor 7 senses the rotation of the motor 12, through which the position of the pushrod M6 can be determined, due to the pushrod gear M5 changing rotational movement of the motor 12 to linear movement of the pushrod M6. [22] The motor speed control volume 8 controls the rotational speed of the motor 12, the pushrod parameter setting volume 9 sets the parameter for movement of the pushrod M6, and the half-clutch setting volume 10 allows a user to set the half-clutch position. The connecting rpm setting volume 11 sets the engine rpms at which clutch engagement commences. [23] The motor 12, according to a control signal from the controller 30, rotates in a forward or reverse direction to move the pushrod M6 linearly backwards or forwards, by means of the pushrod gear M5. When the pushrod M6 moves forward, the clutch disc is disengaged from the flywheel; and when the pushrod M6 moves backward, the clutch disc is engaged to the flywheel. The engine rev booster 13 opens the engine throttle valve to increase engine speed, and the indicator lamp 14 indicates the operation of the controller 30. [24] The controller 30, as described hereinafter, follows a predetermined control process, rotating the motor 12 in a forward or reverse direction, according to inputs from the control switch portion A and values inputted from the sensors, while referring to preset values. The controller 30 also controls the engine rev booster 13, the indicator lamp 14, and the overall system. Additionally, when brake operation is sensed by the brake sensor 6 in low speed mode, the clutch disc is disengaged. [25] Fig. 3 is a control flowchart of the semi auto clutch of the present invention. Referring to Fig. 3, the control process of the present invention includes the following: a clutch disc disengaging stage S1-S9 that disengages the clutch disc by rotating the motor 12 in a forward direction, according to an input signal from the forward button 1 or the brake sensor 6; a half-clutch stage S10-S18 that controls the engine rev booster 13 and drives the motor 12 to position the clutch disc at a half-clutch position, according to an input signal from the half-clutch button 2; and a clutch disc engaging stage S19-S25 that engages the clutch disc, according to an input signal from a rise in engine rpms or the reverse button 3. [26] 1. When the forward button is pressed or brake operation is sensed in low speed mode [27] In order for a user to shift gears, the user can press the forward button 1 located on a surface of the gear shifter or depress the brake pedal, whereupon the brake sensor 6 senses brake operation, which prompts the controller 30 to rotate the motor 12 in a forward direction, which then pushes the pushrod M6 forward via the pushrod gear M5 to push the clutch lever forward for disengaging the clutch disc. [28] In the above disengaged position of the clutch disc, the user is free to shift gears using the gear shifter. [29] After a gear is selected, the controller 30 senses the speed of the engine through the engine rpm sensor 5, and compares the data with a preset rpm value representing the clutch disc engagement point. If the engine speed is higher than the preset rpm value, then the sensed value (the value of the pushrod position based on the rotation of the motor) from the pushrod position sensor 7 is determined, and the motor 12 is rotated in a reverse direction in an amount proportional to the increase in engine rpms, thereby pulling the pushrod M6 via the pushrod gear M5 back to engage the clutch disc. If there is no increase in engine rpms, the motor 12 is not rotated, and the amount of clutch engagement is then based on an engine rpm increase value, so that engine power can be gradually relayed to the transmission. [30] To explain the process differently, when the engine rpms exceed the engagement rpm setting volume 11 that a driver has set as the engine rpm (namely, the engagement rpm), the pushrod is pulled back to engage the clutch disc. The degree of clutch disc engagement is proportional to the increase in engine rpms; and if there is no increase in engine rpms, engagement of the clutch disc is stopped, resulting in half-clutching according to engine speed. [31] Accordingly, whatever the starting conditions of a vehicle may be (for example, being loaded with cargo or disposed facing an incline), the controller can implement the ideal starting conditions for the vehicle based on engine rpm data (which is the most accurate indicator of load on the drive shaft) from the engine rpm sensor 5. That is, the distance the pushrod moves is determined by engine rpms. The pushrod moves only as far as an rpm increase value, so that the speed of engine rpm increase is matched by the speed of pushrod movement. To depart, the driver presses the clutch switch on the gear shifter, engages an appropriate gear, and depresses the accelerator pedal. Due to the resultant engine speed increase, the pushrod M6 moves the clutch disc towards its engagement point with the flywheel by an amount corresponding to the value of the amount and rate of engine speed increase, thereby beginning the engagement of the clutch disc. At this point, the engine starts to be subjected to a load, (which varies from heavy to light). When the load is light, the gradual engagement of the clutch disc is quick; and when the load is heavy, the gradual engagement of the clutch disc is slow until the point where engine power is being transferred almost in its entirety to the transmission, at which time, the half-clutching stage is surpassed due to increased engine speed, and the remainder of clutch engagement occurs rapidly. [32] When there is no change in engine speed, the pushrod M6 stops moving to rest in its current position, so that a half-clutch position is maintained. A vehicle starting up an incline or carrying a heavy load will now be discussed in more detail. In such cases, because there is a heavy load on the drive shaft, when the accelerator pedal Ml is depressed, engine speed does not rise or sluggishly rises because engagement of the clutch disc at half-clutch begins, and the pushrod M6 remains at a virtual standstill. When the driver presses the accelerator pedal Ml further, the opening angle of the throttle valve increases to admit a larger quantity of air-fuel mixture for combustion in the combustion chambers to provide increased power, thus enabling a smooth start. [33] Because the rate of clutch disc engagement is automatically regulated according to engine speed or the rate of engine speed increase, smooth starts can be achieved under all conditions. [34] 2. When the half-clutch button is pressed [35] The half-clutch button 2 is intended to prevent rollback of a vehicle when starting on an incline. When the half-clutch button 2 is pressed, the engine rev booster 13 boosts the speed of the engine by opening the throttle valve, and the clutch disc is moved to a preset position according to the half-clutch setting volume 10. Here, when the increasing engine speed overtakes the engagement rpm value, engagement of the clutch disc occurs. [36] 3. When the reverse button is pressed [37] When the reverse button 3 is pressed to input the reverse button data value, under all circumstances, the motor 12 is rotated in a reverse direction to pull the pushrod M6 back via the pushrod gear M5 and engage the clutch disc. [38] 4. When the low speed mode button is pressed [39] The low speed mode button 4 is used in heavy traffic and stop-and-go conditions that require a driver to press the brake pedal frequently. When the low speed mode button 4 is pressed, the motor 12 is rotated in a forward or reverse direction, depending on changes in engine rpms, to disengage the clutch disc when engine speed drops. [40] While the present invention has been described and illustrated herein with reference to the preferred embodiments thereof, it will be apparent to those skilled in the art that various modifications and variations can be made therein without departing from the spirit and scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention that come within the scope of the appended claims and their equivalents. [41]

Claims

Claims [1] A semi auto clutch driving apparatus for a semi auto clutch that engages and disengages a clutch disc to and from a flywheel by means of a pushrod, the apparatus comprising: a control switch portion for a driver to control the clutch with; an engine rpm sensor for sensing engine speed; a motor for controlling a position of the pushrod by rotating in a forward or reverse direction, according to a control signal; a pushrod position sensor for determining the position of the pushrod by sensing rotation of the motor; a setting portion for setting various reference values; and a controller controlling the motor according to inputs in the control switch portion by comparing engine speed sensed by the engine rpm sensor with a reference rpm set by the setting portion and by determining point and degree of engagement according to an increase in the engine speed and an increase rate thereof, for allowing half-clutching. [2] The apparatus of claim 1, wherein the control switch portion includes: a forward button for disengaging the clutch disc by rotating the motor in a forward direction to push the pushrod forward; a half-clutch button for moving the clutch disc to a half-clutch position; a reverse button for forcibly engaging the clutch disc by rotating the motor in a reverse direction; and a low speed mode button for engaging and disengaging the clutch disc according to an increase or decrease in engine speed. [3] The apparatus of claim 2, further comprising an engine rev booster for boosting engine speed by opening an engine throttle valve according to a control signal, and wherein the controller controls the engine rev booster to boost engine speed when half-clutching is implemented by the half-clutch button. [4] The apparatus of claim 1, wherein the setting portion includes: an engagement rpm setting volume for setting an engagement engine speed; a motor speed control volume for controlling a rotating speed of the motor; a pushrod parameter setting volume for setting a parameter in which the pushrod moves; and a half-clutch setting volume for allowing a user to set a half-clutch position. [5] The apparatus of claim 1, further comprising an indicator lamp for indicating an operation of the controller. [6] A semi auto clutch apparatus driving method comprising: when a forward button is pressed, disengaging a clutch disc by rotating a motor in a forward direction; when a half-clutch button is pressed, controlling an engine rev booster and po¬ sitioning the clutch disc in a half-clutch position; when a low speed mode button is pressed, rotating the motor in a forward or reverse direction according to engine speed, and if the enginge speed decreases, disengaging the clutch disc; and when engine speed increases or when a reverse button is pressed, engaging the clutch disc. [7] A semi auto clutch apparatus driving method comprising: detecting engine speed to determine whether the engine speed reaches an engagement rpm; if so, engaging a clutch disc by moving a pushrod according to an amount and rate of an increase in engine speed; and if not, stopping the engaging of the clutch disc.