Claims:WE CLAIM:
1. A manual transmission system comprising a gearbox for changing the ratio between the torque generated by the engine and the torque received by the wheels of the vehicle, said gearbox configured to displace the vehicle in a creeping mode.
2. The system as claimed in claim 1, wherein said system comprises:
a. a creep gear combination in the gearbox 20, said creep gear combination configured to be engaged by the operator for putting said transmission system in said creeping mode;
b. a clutch actuator 50 configured to control the degree of engagement / disengagement of the clutch 30;
c. a control unit 60 configured to control the engine 10 and the clutch actuator 50, wherein, on detection of the transmission system in said creeping mode, said control unit 60 is configured to:
i. maintain the clutch 30 of the transmission system in predetermined state of engagement irrespective of the degree of depression of the clutch pedal/lever; and
ii. vary the speed of rotation of the engine 10 based on the degree of depression of the brake pedal of the vehicle, to allow the vehicle’s operator to control the speed of the vehicle using the brake pedal.
3. The system as claimed in claim 2, wherein said creep gear combination is configured to be engaged by the operator by shifting a gear shift lever 70 to a creep gear position.
4. The system as claimed in claim 2, wherein said predetermined state of engagement of said clutch 30 is a fully engaged state or a partially engaged state.
5. The system as claimed in claim 2, wherein said vehicle comprises a brake pedal depression sensor configured to generate a brake pedal depression signal “B” corresponding to the degree of depression of the brake pedal.
6. The system as claimed in claim 5, wherein said control unit 60 varies the speed of rotation of the engine 10 in inverse proportion to the magnitude of said brake pedal depression signal “B”.
7. The system as claimed in claim 6, wherein said control unit 60 is configured to limit the speed of the vehicle between a predetermined minimum creep speed and a predetermined maximum creep speed.
8. The system as claimed in claim 7, wherein said control unit 60 controls the actuation of a fuel injection pump of the engine 10 of the vehicle for varying the speed of the engine 10.
9. The system as claimed in claim 2, wherein said clutch actuator 50 is configured to control the pressure of the hydraulic fluid delivered to said clutch 30 through a clutch slave cylinder 40.
10. The system as claimed in claim 3, wherein the gear ratio of the gear combination corresponding to the creep gear position of the gear shift lever 70 is determined to achieve the wheel speed till 20 kmph.
11. The system as claimed in claim 2, wherein said vehicle comprises a brake gear sensor configured to sense the position of said gear shift lever 70 and generate a gear position signal “S” corresponding to the sensed gear position.
12. The system as claimed in claim 1, wherein said vehicle is a four-wheeled automobile.
13. The system as claimed in claim 1, wherein said vehicle is a two-wheeled vehicle.
14. The system as claimed in claim 1, wherein said vehicle is a three-wheeled vehicle.
15. The system as claimed in claim 1, wherein said vehicle is a multi-axle vehicle.
, Description:FIELD
The present disclosure relates to the field of manual transmission systems.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
A four-wheeled automobile with manual transmission has a clutch pedal, an accelerator (or throttle) pedal and a brake pedal, along with the steering wheel and the hand-operated shifting lever for controlling the movement of the automobile. Usually, the clutch pedal is operable using the left foot and the brake pedal and the accelerator pedal are alternatingly operable using the right foot of the driver. When the automobile is manoeuvred through a heavy traffic, the driver is required to be continuously operating the clutch pedal while alternating between the brake pedal and the accelerator pedal. After spending a while creeping the automobile in this manner in a highly unpredictable and risk-filled traffic, a significant amount of fatigue is induced in the muscles of the legs. Consistent exposure to such stresses may culminate in critical orthopaedic conditions. The involved mental stress can cause a lapse in the driver’s concentration and thus heighten the risk of accidents. Automobiles with automatic transmission and automated manual transmission indeed require less effort and induce less fatigue in comparison. However, they still are not available at affordable prices for the middle class of purchasers.
There is, therefore, felt a need for providing a transmission system which ameliorates the aforementioned issues.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
An objective of the present disclosure is to provide a manual transmission system.
Another objective of the present disclosure is to provide a manual transmission system of a vehicle, which induces less fatigue while creeping the vehicle through heavy traffic.
Yet another objective of the present disclosure is to provide a manual transmission system of a vehicle, which is cost-effective.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure envisages a manual transmission system.
The transmission system comprises a gearbox for changing the ratio between the torque generated by the engine and the torque received by the wheels of the vehicle, wherein the gearbox is configured to displace the vehicle in a creep gear mode.
The system comprises a creep gear addition on the existing transmission unit, a clutch actuator, and a control unit. The creep gear combination is configured to be engaged by the operator for putting the transmission system of the vehicle in the creeping mode. The clutch actuator is configured to control the degree of engagement of the clutch. The control unit is configured to control the engine and the clutch actuator, wherein, on detection of the transmission system in the creep gear mode, the control unit is configured to:
i. maintain the clutch of the transmission system in predetermined state of engagement irrespective of the degree of depression of the clutch pedal/lever; and
ii. vary the speed of rotation of the engine based on the degree of depression of the brake pedal of the vehicle, to allow the vehicle’s operator to control the speed of the vehicle using the brake pedal.
In an embodiment, the creep gear combination is configured to be engaged by the operator by shifting a gear shift lever to a creep gear position
Preferably, the predetermined state of engagement of the clutch in the creep gear mode is a fully engaged state or a partially engaged state.
In an embodiment, the control unit varies the speed of rotation of the engine in inverse proportion to the magnitude of the brake pedal depression signal.
Preferably, the control unit is configured to limit the speed of the vehicle between a predetermined minimum creep speed and a predetermined maximum creep speed. In an embodiment, the control unit controls the actuation of a fuel injection pump of the engine of the vehicle for varying the speed of the engine.
In an embodiment, the clutch actuator is configured to control the pressure of the hydraulic fluid delivered to the clutch through a clutch slave cylinder.
In an embodiment, the gear ratio of the gear combination corresponding to the creep gear position of the gear shift lever 70 is determined to achieve the wheel speed till 20 kmph.
In an embodiment, the vehicle comprises a gear sensor configured to sense the position of the gear shift lever and generate a gear position signal “S” corresponding to the sensed gear position.
In an embodiment, the vehicle comprises a brake pedal depression sensor configured to generate a brake pedal depression signal corresponding to the degree of depression of the brake pedal.
In an embodiment, the vehicle is a four-wheeled automobile. In another embodiment, the vehicle is a two-wheeled vehicle. In yet another embodiment, the vehicle is a three-wheeled vehicle. In another embodiment, the vehicle is a multi-axle vehicle.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
The manual transmission system of the present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates a schematic view of a control system of a clutch of prior art;
Figure 2 illustrates a schematic view of a gear shift knob representing a gear shift lever of prior art;
Figure 3 illustrates a schematic view of a control system of a clutch of the present disclosure;
Figure 4 illustrates a schematic view of a gear shift knob representing a gear shift lever of the present disclosure;
Figure 5 illustrates a control flow diagram of the transmission system of the present disclosure.
LIST OF REFERENCE NUMERALS
1000’ control system of a clutch of prior art
1000 control system of a clutch of the present disclosure
10 engine
20 gearbox
30 clutch
40 slave clutch cylinder
50 clutch actuator
60 control unit
62 engine control unit
64 clutch control unit
70’ gear shift lever of prior art
70 gear shift lever of the present disclosure
1 first gear position
2 second gear position
3 third gear position
4 fourth gear position
5 fifth gear position
R reverse gear position
T creep gear position
B brake pedal depression signal
C clutch pedal actuation
S gear position signal
M miscellaneous signals
DETAILED DESCRIPTION
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms “comprises”, “comprising”, “including” and “having” are open-ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
When an element is referred to as being “mounted on”, “engaged to”, “connected to” or “coupled to” another element, it may be directly on, engaged, connected or coupled to the other element. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed elements.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Terms such as “inner”, “outer”, “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used in the present disclosure to describe relationships between different elements as depicted from the figures.
A manual transmission system generally comprises a gearbox 20 which comprises a set of driving gears and driven gears. The driving gears are mounted on a driving shaft which receives power from the crankshaft of the engine 10. The driven gears are mounted on a driven shaft. The driven gears are driven by the driving gears. The power is transmitted from the driven shaft to the axles of the wheels of the automobile through a drive line / propeller shaft. A mechanical clutch 30 is configured to bring about engagement or disengagement between the driving shaft and the driven shaft. The clutch is generally air-assisted / hydraulically actuated through a clutch pedal. The clutch pedal actuation ‘C’ is transmitted to the clutch 30 through the slave clutch cylinder 40, as shown in Figure 1. The selection of speed ratio of transmission between the driving shaft and the driven shaft, i.e., the pair of a driving gear and a driven gear being in engagement is determined through a shifting mechanism which is actuated through a shift lever 70’ having a first gear position 1, a second gear position 2, a third gear position 3, a fourth gear position 4, a fifth gear position 5 and a reverse gear position R, as represented by the knob shown in Figure 2. The speed of rotation of the engine 10 is governed primarily through the accelerator pedal. The degree of application of brakes is controlled through a brake pedal.
The actuation of a clutch pedal and a brake pedal, in spite of accounting for the available hydraulic assistance as well as mechanical leverage respectively, requires significant effort, which gets compounded to induce fatigue when applied repeatedly in a heavy traffic situation, in which the vehicle is creeping alongwith the slowly moving traffic. Moreover, a considerable amount of mental fatigue is also caused while driving due to the continuous involvement of the limbs – the left leg operating the clutch pedal and the right leg switching between the brake pedal and the accelerator pedal. Moreover, the gear shift lever 70’ is also continuously manipulated between the positions corresponding to the higher gear ratios, thus inducing fatigue in the hand.
A cost-effective solution is required which makes creeping vehicle through a heavy traffic easy without causing a lot of physical or psychological stress to the operator.
The present disclosure envisages a manual transmission system of a vehicle with a creep mode for moving in heavy traffic. In a preferred embodiment, which is implemented in an automobile, the transmission system of the present disclosure, hereinafter referred to as “transmission system” comprises a gear shift lever 70 having a creep gear position T, a gear combination in the gearbox which is engageable by shifting the gear shift lever 70 in the creep gear position T, a brake pedal sensor for sensing the degree of depression of the brake pedal, a gear sensor for sensing the currently engaged gear combination of the gearbox 20, a clutch actuator 50 for controlling the actuation of the clutch 30 and a control unit 60 for controlling the clutch actuator 50 and the speed of rotation of the engine 10.
The gear shift lever 70, as represented by the knob shown in Figure 4, is configured to be shifted into a creep gear position T apart from the conventional regular first gear position 1, second gear position 2, third gear position 3, fourth gear position 4, fifth gear position 5, reverse gear position R and the neutral gear positions.
The gearbox 20 of the automobile is configured with a creep gear combination. Changing the engaged pair of gears of the gearbox changes the ratio between the torque generated by the engine and the torque received by the wheels of the vehicle. The gearbox is configured to be engaged, using the shifting mechanism actuated by operating the gear shift lever 70, into a creeping mode of transmission. In an embodiment, a driving creep gear and a driven creep gear is fitted on the driving shaft and the driven shaft respectively. In another embodiment, a driving creep gear engageable with one of the driven gears corresponding to the first, second, third, fourth, fifth gear positions is fitted on the driving shaft. In yet another embodiment, a driven creep gear engageable with one of the driving gears corresponding to the first, second, third, fourth, fifth gear positions is fitted on the driven shaft. In an embodiment, the ratio of transmission of speed is the lowest, or in other words, the ratio of transmission of torque is the highest, from the driving shaft to the driven shaft of the gearbox 20 shifted in the creep gear combination, amongst all the positions of the gear shift lever 70. In an embodiment, the gear ratio is determined to achieve the wheel speed till 20kmph of the gear combination corresponding to the creep gear position of the gear shift lever 70.
The brake pedal sensor is installed in the driver compartment for sensing the degree of depression of the brake pedal. The brake pedal sensor is configured to generate an analog linear output signal “B” corresponding to the angular displacement of the brake pedal. In an embodiment, the brake pedal sensor is an angle sensor having an element which is coupled to the brake pedal and which undergoes rotation due to the displacement of the brake pedal. The brake pedal sensor is communicatively coupled to the control unit 60.
In an embodiment, the gear sensor is installed in the driver compartment for sensing position of the gear shift lever 70. The gear sensor is configured to generate a discrete gear position signal “S” for each position – first gear position 1, second gear position 2, third gear position 3, fourth gear position 4, fifth gear position 5, reverse gear position R and creep gear position T. The gear sensor is communicatively coupled to the control unit 60.
The clutch actuator 50, of the clutch actuation system 1000 of the present disclosure shown in Figure 3, is an electrically operated actuator. In an embodiment, the clutch actuator 50 is configured to control the degree of engagement or disengagement of the clutch 30 by controlling the pressure of the hydraulic fluid delivered to the clutch 30 through a clutch slave cylinder 40. In another embodiment, the clutch actuator 50 is configured to change the state of the clutch 30 between engagement and disengagement through the clutch slave cylinder 40.
The control unit 60 is configured to receive a plurality of signals corresponding to the sensed parameters, which includes the signal from the gear sensor, i.e., the gear position signal “S” and the signal from the brake pedal sensor, i.e., brake pedal depression signal “B”, besides a plurality of miscellaneous signals “M” received from sensors sensing the engine parameters including speed of rotation, temperature, air intake volume and so on. The control unit is normally configured to control speed of rotation of the engine by controlling the fuel intake, air intake, ignition timing and so on. In an embodiment, the control unit 60 is a centralized control unit configured to control the engine 10 as well as the clutch actuator 50. In another embodiment, the control is distributed by providing an engine control unit 62 configured to control the operating parameters of the engine 10 and a clutch control unit 64 configured to control the clutch actuator 50 for controlling actuation of the clutch 30, as illustrated in Figure 5.
According to an aspect of the present disclosure, when the gear shift lever 70 is detected in a creep gear position “T”, i.e., in a creeping mode, the control unit 60 is configured to control the clutch actuator 50 to maintain the clutch 30 in a predetermined state of engagement and to vary the speed of rotation of the engine 10 in accordance with the brake pedal depression signal “B”. In an embodiment, the state of engagement of the clutch 30 maintained by the clutch actuator 50 in the creeping mode is a fully engaged state. In another embodiment, the state of engagement of the clutch 30 maintained by the clutch actuator 50 in the creeping mode is a partially engaged state. In an embodiment, the speed of rotation of the engine 10 is controlled by the control unit 60 by controlling the operation of a fuel injection pump. In an embodiment, the control unit 60 controls the speed of rotation of the engine 10 to maintain the speed of the automobile within a predetermined minimum creep speed and a maximum creep speed. In an embodiment, the predetermined creep speed range is 0 kmph to 20 kmph respectively.
Thus, the vehicle with the manual transmission system of the present disclosure is configured to allow the operator to control the speed of the automobile in the creeping mode using the brake pedal only. In case of the embodiment of an automobile elaborated hereinabove, while moving in a congested traffic, the operator of the automobile only needs to shift the gear shift lever 70 in the creep gear position “T” and use the brake pedal to vary the speed of the automobile, i.e., release the brake pedal to run the automobile at the predetermined maximum creep speed, e.g., 20 kmph, and depress the brake pedal upto a predetermined minimum extent to run the automobile at the predetermined minimum creep speed which could any magnitude of speed less than 20 kmph. Therefore, the operator is not required to simultaneously operate the clutch pedal or the accelerator pedal alongwith the brake pedal, and hence, is relieved of the mental and physical fatigue that would have otherwise been generated, making driving through heavy traffic more comfortable and safe. The operator can shift the gearbox 20 back to the conventional gears once the traffic becomes decongested.
Moreover, the incorporation of the creeping mode in a vehicle having manual transmission of the present disclosure is more cost-effective in comparison with vehicles having automatic transmission system or automated manual transmission system.
In another embodiment, the manual transmission system is implemented in a two-wheeled vehicle. In yet another embodiment, the manual transmission system is implemented in a three-wheeled vehicle. In still another embodiment, the manual transmission system is implemented in a multi-axle vehicle.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a manual transmission system with a creeping mode, which:
• induces less fatigue while creeping the vehicle through heavy traffic; and
• cost-effective.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.