Description:FIELD OF INVENTION

The present invention relates to a clutch housing. In particular, the present invention relates to a controlled ventilation inside a clutch housing. More particularly, the present invention relates to an active monitoring of the temperature inside the clutch housing for reducing the dust entry therein.

BACKGROUND OF THE INVENTION

The first stage of the transmission of an automobile includes a clutch assembly, which has the object of transmitting power to the gearbox and also to allow an interruption of this power transmission whenever a gear is selected to move-off from a stationary position or whenever gears are changed during the movement of an automobile. The clutch may be configured as a friction clutch operated either by fluid (hydraulic) or often by a cable.

Under power transmission, the automobile clutch is engaged and a pressure plate fitted to the flywheel applies a constant force on the driven (friction) plate by means of a diaphragm spring. The friction plate runs on a splined input shaft to transmit power to the gearbox. This friction plate has friction linings on both faces thereof, like brake linings, to facilitate a smoother drive during the clutch engagement.

On disengaging the clutch by depressing the clutch pedal, an arm pushes a release bearing against the center of a diaphragm spring for releasing the clamping pressure exerted by the pressure plate and the outer part of the pressure plate having a large friction surface, releases the clamping of the driven (friction) plate to the flywheel, thus power transmission is interrupted and gears can now be changed/shifted.

Accordingly, a clutch housing accommodates different sub-systems like clutch release bearing, clutch-assembly and input shaft therein. Due to friction of the clutch disc assembly with the cover assembly and flywheel during operation, substantial heat is generated while engaging and dis-engaging the clutch.

This heat remains trapped inside the clutch housing, and thus leads to a reduced life of the clutch assembly. In order to release this heat trapped inside the clutch housing, one or more ventilation slots is/are provided on the clutch housing exterior surface.

These ventilation slots follow the principle of free-convection i.e., one ventilation slot acts as an inlet for air entry and one as an outlet for air entry. Alternatively, both the ventilation slots act as an inlet for the entry of air inside.

Although, these ventilation slots or openings on the clutch housing assists in the ventilation, at the same time, since it is open, it also allows to pull dust particles inside the clutch housing. This obviously degrades the functionality of the clutch assembly.

DISADVANTAGES OF THE PRIOR ART

The existing clutch housing is configured with one or more ventilation hole/s to dissipate the heat generated inside the clutch housing, as discussed above, to retain the targeted clutch life. Generally, the ventilation hole/s act/s as an air inlet and outlet depending upon the location of the hole on the clutch housing and the amount of pressure generated therein. However, the ventilation hole remains open throughout and performs its basic function of the air inlet into / air outlet from the clutch housing, it also allows dust to enter the clutch housing.

Since the clutch hydraulic release systems are more sensitive to dust, this often causes the failure of the sub-systems inside the clutch housing.

Therefore, there is an existing need for providing an arrangement on clutch housing, whereby the dust entry inside the clutch housing is substantially reduced or even stopped as much as possible, in order to reduce/eliminate the failure of the various sub-systems accommodated inside clutch housing.

DESCRIPTION OF THE INVENTION

In accordance with the present invention, an active ventilation system in clutch housing is configured with a ventilation hole having a ventilation hole closure controlled by a solenoid valve and a spring return arrangement to reduce the amount of dust entering inside the clutch housing during ventilation thereof. This solenoid valve is triggered by an Electronic Control Unit (ECU) and the ventilation hole closure is triggered to be opened based on the temperature detected inside the clutch housing. The temperature is continuously monitored with the help of thermocouples placed inside the clutch housing.

OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:

An object of the present invention is to provide an active ventilation system in clutch housing which opens the ventilation hole thereof by continuously monitoring the temperature therein.

Another object of the present invention is to provide an active ventilation system in clutch housing offering a controlled ventilation thereof.

Still another object of the present invention is to provide an active ventilation system in clutch housing which substantially reduces or even eliminates the entry of dust particles as much as possible.

Yet another object of the present invention is to provide an active ventilation system in clutch housing which substantially increases the life of the clutch assembly.

A further object of the present invention is to provide an active ventilation system in clutch housing which is easy to manufacture and maintain.

A still further object of the present invention is to provide an active ventilation system in clutch housing which is low-cost to manufacture and maintain.

A yet further object of the present invention is to provide an active ventilation system in clutch housing which can also be easily retrofitted on the ventilation slots/holes of the existing clutch housings.

These and other objects and advantages of the present invention will become more apparent from the following description, when read with the accompanying figures of drawing, which are however not intended to limit the scope of the present invention in any way.

SUMMARY OF INVENTION

In accordance with the present invention, there is provided an active ventilation system in clutch housing (CH) of an automobile, said active ventilation system comprises:

• a ventilation slot (VS) configured on said clutch housing (CH);

• a shutter (SH) configured on said clutch housing (CH);
• one or more spring/s (S) with one end thereof fixed on said clutch housing (CH); and/or

• a valve (V) connected between said clutch housing (CH) and the other end of said spring/s (S); and

• an arrangement to control the movement of said valve (V);

wherein said arrangement controls the movement of said shutter (SH) for opening or closing thereof, depending on the temperature prevailing inside said clutch housing (CH), and continuously monitors and maintains a preset threshold temperature inside said clutch housing (CH).

Typically, the shutter (SH) is linearly moveable along a pair of guideways (GW) configured on either side of said ventilation slot (VS).

Typically, the spring is a coil spring (CS) fixed between said shutter (SH) and clutch housing (CH).

Typically, the valve is a solenoid valve (SV) fixed between said shutter (SH) and clutch housing (CH), and said clutch housing (CH) is fitted inside with a plurality of thermocouples located therein.

Typically, the valve (V) is operated by a hydraulic pump.

Typically, the valve (V) is operated by a pneumatic pump creating a negative-pressure/vacuum using a pump-line (PL) used for operating the brakes of said automobile.

Typically, the valve (V) comprises a piston-cylinder (PC) arrangement connected between said shutter (SH) and clutch housing (CH) and supplied with negative-pressure/vacuum via said pump-line (PL).
Typically, the valve (V) is configured as a wax element (W) connected between said shutter (SH) and clutch housing (CH), said wax element (W) comprises a cylinder filled with wax and fitted with a pin inside attached to said shutter (SH) for movement thereof by means of a heating element (HE) attached to said cylinder for heating said wax filled therein.

Typically, the arrangement to control the movement of said valve (V) is an Electronic Control Unit (ECU), preferably a microcontroller.

Typically, the Electronic Control Unit (ECU) controls the movement of said shutter (SH).

Typically, the spring is a shape memory alloy spring (SMAS) fixed between said shutter (SH) and clutch housing (CH).

Typically, the shape memory alloy spring (SMAS) controls the movement of said shutter (SH) in the following manner:

(i) when the temperature prevailing inside said clutch housing (CH) is below said preset threshold temperature, said shape memory alloy spring (SMAS) contracts to close said shutter (SH); or

(ii) when the temperature prevailing inside said clutch housing (CH) is same as the said preset threshold temperature, said shape memory alloy spring (SMAS) expands or elongates to open said shutter (SH); or

(iii) when the temperature prevailing inside said clutch housing (CH) again falls below said preset threshold temperature, said shape memory alloy spring (SMAS) contracts again to close said shutter (SH).

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will be briefly described in the following with reference to the accompanying drawings.

Figure 1 shows a perspective view of a conventional clutch housing accommodating several components and/or sub-assemblies of the clutch assembly and marked with the region of a ventilation slot provided therein.

Figure 2 shows an enlarged view of the region of a ventilation slot/hole marked on the conventional clutch housing depicted in Figure 1.

Figure 3 shows a schematic arrangement of an active ventilation system configured in accordance with the present invention in a clutch housing provided a ventilation slot/hole having a closure controlled by a solenoid valve and a spring return arrangement.

Figure 4 shows a schematic diagram of the operation of the active ventilation system configured in accordance with the present invention and as shown in Figure 3.

Figure 5 shows an embodiment of the active ventilation system configured in accordance with the present invention, in which a hydraulic system with a separate hydraulic pump controls the shutter by using a valve, the opening and closing of which is ECU-controlled.

Figure 6 shows a schematic diagram of the operation of the active ventilation system configured in accordance with the present invention, in which a shape memory alloy changes its shape based on the temperature experienced by it.

Figure 7 shows another embodiment of the active ventilation system configured in accordance with the present invention, in which a wax element is attached to shutter and clutch housing.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

In the following, the active ventilation system configured in accordance with the present invention will be described in more details with reference to the accompanying drawings without limiting the scope and ambit of the present invention.

Figure 1 shows a perspective view of a conventional clutch housing CH accommodating several components and/or sub-assemblies of the clutch assembly and marked with the region of a ventilation slot VS provided therein.

Figure 2 shows an enlarged view of the region of a ventilation slot VS marked on the conventional clutch housing CH depicted in Figure 1.

Figure 3 shows a schematic arrangement of an active ventilation system configured in accordance with the present invention in a clutch housing CH provided with a ventilation slot VS having a closure or shutter SH linearly moving in the direction of arrow LM controlled by a solenoid valve SV and a return arrangement with a coil-spring CS.

Figure 4 shows a schematic diagram of the operation of the active ventilation system configured in accordance with the present invention on a clutch housing CH provided with a ventilation slot VS and as shown in Figure 3. Here, a closure arrangement for opening or closing ventilation slot VS of the clutch housing CH is disclosed. The clutch housing CH includes an active temperature monitoring device TMD. The clutch housing CH also includes 3 main components, i.e. a coil-spring CS, a shutter SH and a solenoid valve SV controlled by an Electronic Control Unit (ECU) linked to a plurality of thermocouples located inside clutch housing CH. This ECU continuously monitors the temperature inside the clutch housing until the automobile engine is turned-off. This ECU is pre-set with a threshold temperature limit. When the temperature inside the clutch housing CH crosses this threshold temperature limit, the solenoid valve triggers the shutter SH to slide along the guideway arrangement (not shown) provided in the clutch housing CH. One end of the shutter SH is connected to the coil-spring CS and other end thereof is connected to solenoid valve SV. Once the solenoid valve SV triggers, the shutter SH is pulled and thus the ventilation slot VS is opened for an active ventilation arranged in accordance with the present invention. When ECU recognizes that the temperature is reduced within the pre-set threshold limits thereof, it deenergizes the solenoid valve SV, and the coil-spring CS connected at the other end of the shutter pulls it back and retains it in the ventilation slot VS closed position.

Figure 5 shows an embodiment of the active ventilation system configured in accordance with the present invention, in which a hydraulic system (e.g., piston and cylinder arrangement PC) with a separate hydraulic pump controls the linear movement LM of the shutter SH linearly moving in the direction of arrow LM by using an ECU-controlled valve V for opening and closing thereof. A pneumatic vacuum pump normally attached to Internal Combustion Engine (ICE) in automobiles creates a negative pressure/vacuum, which is to apply brakes and same vacuum pump-line PL operates the shutter SH by the valve V controlled by the ECU.

Figure 6 shows shape memory alloy springs SMAS attached in a cooled stretched condition. The springs are located inside the clutch housing to sense the temperature therein. Here, the shape memory alloy spring SMAS changes its shape based on the temperature experienced by it. Unlike above embodiments of the present invention, no thermocouple or ECU or valve V is required. Rather, one end of this shape-memory alloy springs SMAS is attached to the clutch housing CH and the other end thereof is attached to the shutter SH. When the temperature within the clutch housing CH is below the preset threshold limit, the springs SMAS are in contraction and shutter SH is closed. When the temperature within the clutch housing CH reaches said threshold limit and the springs SMAS elongate to open the shutter SH for opening the ventilation slot VS. When the temperature within the clutch housing CH again falls below said threshold limit, the springs SMAS contracts and the shutter SH closes back.

Figure 7 shows another embodiment of the active ventilation system configured in accordance with the present invention, in which a wax element W is attached between the shutter SH and the clutch housing CH by means of a coil-spring CS. This wax element W consists of a piston-cylinder P/P filled with wax and a pin inside this cylinder P/P is attached to shutter SH. A heating element HE is attached to this cylinder P/P controlled by the ECU. By increasing the temperature of this heating element HE, the wax W inside the cylinder P/P expands to move the pin to open the shutter SH and vice-versa.

TECHNICAL ADVANTAGES AND ECONOMIC SIGNIFICANCE

The active ventilation in the clutch housing configured in accordance with the present invention offers the following advantages:

 Controlled ventilation inside the clutch housing.

 Less dust entry due to the controlled ventilation.

 Active monitoring of the temperatures inside the clutch housing for obtaining a longer life of the clutch.

The foregoing description of the specific embodiments will 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 distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation. The exemplary embodiments described in this specification are intended merely to provide an understanding of various manners in which this embodiment may be used and to further enable the skilled person in the relevant art to practice this invention.

Although, the embodiments presented in this disclosure have been described in terms of its preferred embodiments, the skilled person in the art would readily recognize that these embodiments can be applied with modifications possible within the spirit and scope of the present invention as described in this specification by making innumerable changes, variations, modifications, alterations and/or integrations in terms of materials and method used to configure, manufacture and assemble various constituents, components, subassemblies and assemblies, in terms of their size, shapes, orientations and interrelationships without departing from the scope and spirit of the present invention.

The numerical values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the disclosure unless there is a statement in the specification to the contrary.

Throughout this specification, the word “comprise”, or variations such as “comprises” or “comprising”, shall be understood to imply including a described element, integer or method step, or group of elements, integers or method steps, however, does not imply excluding any other element, integer or step, or group of elements, integers or method steps.

The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention.

The description of the exemplary embodiments is intended to be read in conjunction with the accompanying drawings, which are to be considered part of the entire written description. In the description, relative terms such as “lower”, “upper”, “horizontal”, “vertical”, “above”, “below”, “up”, “down”, “top”, and “bottom” as well as derivatives thereof (e.g. “horizontally”, “inwardly”, “outwardly”; “downwardly”, “upwardly” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion.

These relative terms are for convenience of description and do not require that the corresponding apparatus or device be constructed or operated in a particular orientation. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected”, refer to a relationship, wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. , Claims:We claim:

1. An active ventilation system in clutch housing (CH) of an automobile, said active ventilation system comprises:

• a ventilation slot (VS) configured on said clutch housing (CH);

• a shutter (SH) configured on said clutch housing (CH);

• one or more spring/s (S) with one end thereof fixed on said clutch housing (CH); and/or

• a valve (V) connected between said clutch housing (CH) and the other end of said spring/s (S); and

• an arrangement to control the movement of said shutter (SH);

wherein said arrangement controls the movement of said shutter (SH) for opening or closing thereof, depending on the temperature prevailing inside said clutch housing (CH), and continuously monitors and maintains a preset threshold temperature inside said clutch housing (CH).

2. The active ventilation system as claimed in claim 1, wherein said shutter (SH) is linearly moveable along a pair of guideways (GW) configured on either side of said ventilation slot (VS).

3. The active ventilation system as claimed in claim 1, wherein said spring is a coil spring (CS) fixed between said shutter (SH) and said clutch housing (CH).

4. The active ventilation system as claimed in claim 1, wherein said valve is a solenoid valve (SV) fixed between said shutter (SH) and said clutch housing (CH), and said clutch housing (CH) is fitted inside with a plurality of thermocouples located therein.

5. The active ventilation system as claimed in claim 1, wherein said valve (V) is operated by a hydraulic pump.

6. The active ventilation system as claimed in claim 1, wherein said valve (V) is operated by a pneumatic pump creating a negative-pressure/vacuum using a pump-line (PL) used for operating the brakes of said automobile.

7. The active ventilation system as claimed in claim 6, wherein said valve (V) comprises a piston-cylinder (PC) arrangement connected between said shutter (SH) and said clutch housing (CH) and supplied with negative-pressure/vacuum via said pump-line (PL).

8. The active ventilation system as claimed in claim 1, wherein said valve (V) is configured as a wax element (W) connected between said shutter (SH) and said clutch housing (CH) by means of a coil-spring (CS), said wax element (W) comprises a cylinder filled with wax and fitted with a pin inside attached to said shutter (SH) for movement thereof by means of a heating element (HE) attached to said cylinder for heating said wax filled therein.

9. The active ventilation system as claimed in claim 1, wherein said arrangement to control the movement of said valve (V) is an Electronic Control Unit (ECU), preferably a microcontroller.

10. The active ventilation system as claimed in claim 9, wherein said Electronic Control Unit (ECU) controls the movement of said shutter (SH).

11. The active ventilation system as claimed in claim 1, wherein said spring is a shape memory alloy spring (SMAS) fixed between said shutter (SH) and said clutch housing (CH).

12. The active ventilation system as claimed in claim 11, wherein said shape memory alloy spring (SMAS) controls the movement of said shutter (SH) in the following manner:

(i) when the temperature prevailing inside said clutch housing (CH) is below said preset threshold temperature, said shape memory alloy spring (SMAS) contracts to close said shutter (SH); or

(ii) when the temperature prevailing inside said clutch housing (CH) is same as said preset threshold temperature, said shape memory alloy spring (SMAS) expands or elongates to open said shutter (SH); or

(iii) when the temperature prevailing inside said clutch housing (CH) again falls below said preset threshold temperature, said shape memory alloy spring (SMAS) contracts again to close said shutter (SH).

Dated this 30th day of March 2023.

Digitally / e-Signed by:

(SANJAY KESHARWANI)
APPLICANT’S PATENT AGENT
REGN. NO. IN/PA-2043.