FORM 2
THE PATENT ACT, 1970
(39 of 1970)
&
THE PATENTES RULES, 2005
COMPLETE SPECIFICATION
(See section 10, rule 13)
1. TITLE OF THE INVENTION
"Mechanism for Operating a Vacuum Pump and a High Pressure Pump"
2. APPLICANT(S)
(a) Name : MAHINDRA & MAHINDRA LIMITED
(b) Nationality : Indian Company registered under the provisions
of the Companies Act, 1956
(c) Address : R&D Center, Automotive Sector,
89, M.I.D.C., Satpur, NASHIK - 422 007 Maharashtra State, India
3. PREAMBLE OF THE DESCRIPTION
COMPLETE
The following specification particularly describes the invention and the manner in which it is to be performed.

Field of the invention
The present invention relates to a mechanism for operating a vacuum pump and a high pressure pump by using drive from an engine of an automobile, and more particularly, to using single drive for operating a vacuum pump and a pressure pump of the engine of the automobile.
Background of the invention
Generally, a vacuum pump is integrated on alternator, and is driven by an alternator pulley and a belt drive system. The alternator rotates at very high speed leading to frictional losses while transferring torque from the alternator pulley to the vacuum pump.
Further, another arrangement is provided to drive the vacuum pump through slot in a camshaft. This arrangement is possible only with overhead camshaft and has packaging constraints. In case of push rod engines, the position of the camshaft is at low level in crankcase interference with bell housing at rear.
Accordingly, there exist needs to provide a mechanism, which can drive both the high pressure pump and the vacuum pump from a single driving means.
Objects of the invention
An object of the present invention is to provide a mechanism, which is capable of driving both a high pressure pump and a vacuum pump from a single driving means.
Another object of the present invention is to provide a mechanism for driving high pressure pump and a vacuum pump of an automobile, which enables effective braking system for vehicles.

Yet another object of the present invention is to provide a mechanism for driving high pressure pump and a vacuum pump of an automobile, which is easy to access and repair.
One more object of the present invention is to provide a mechanism for driving high pressure pump and a vacuum pump of an automobile, which is easy to manufacture and robust in construction.
Further object of the present invention is to provide a mechanism for driving high pressure pump and a vacuum pump of an automobile, which is economical to construct.
Summary of the invention
Accordingly, the present invention provides a mechanism for operating a vacuum pump and a high pressure pump using drive from engine of an automobile, the high pressure pump comprising a first drive shaft for mounting a sprocket wheel thereon, and the vacuum pump comprising a second drive shaft, the high pressure pump and the vacuum pump having opposite rotating orientation, characterized in that, the mechanism comprises,
a nut having an internally threaded portion and a slot configured on one end thereof, wherein the first drive shaft of the high pressure pump is secured to the to the internally threaded portion, and the second drive shaft of the vacuum pump is secured to the slot such that the first drive shaft and the second drive shaft are facing each other,
wherein upon rotating the sprocket wheel by the drive from the engine, the high pressure pump rotates in clock-wise direction and the vacuum pump rotates in anti-clock-wise direction.
Brief description of drawings

Figure 1 shows a sectional front view of a mechanism (100) along with a crank case (50) in accordance with the present invention;
Figure 2 shows an enlarged sectional front view of a mechanism of figure 1; and
Figure 3 shows an enlarged perspective view of a nut of the mechanism of figure 1.
Detailed description of the invention
The foregoing objects of the invention are accomplished and the problems and shortcomings associated with the prior art techniques and approaches are overcome by the present invention as described below in the preferred embodiment.
The present invention provides a mechanism for driving a high pressure pump and a vacuum pump of an automobile. The mechanism is capable of driving both high pressure pump and a vacuum pump from a single driving means. Further, the mechanism enables effective braking system for vehicles. Furthermore, the mechanism is easy to access and repair. Moreover, the mechanism is easy to manufacture, robust in construction and economical to construct.
This present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description.
Referring now to figures 1 and 2, there is shown a sectional front view of a mechanism (100) for operating a high pressure pump (10) and a vacuum pump

(20) using drive from the engine of the automobile in accordance with the present invention.
The high pressure pump (10) includes a first drive shaft (12) for mounting a sprocket wheel (30) thereon. Further, the vacuum pump (20) includes a second drive shaft (22). The high pressure pump (10) and the vacuum pump (20) are selected such that they have opposite rotating orientation.
The improvement in the mechanism comprises a nut (40) as shown in figure 3. The nut (40) includes internally threaded portion (not shown) and a slot (42) configured on one end/free end thereof.
The first drive shaft (12) of the high pressure pump (10) is secured to the to the internally threaded portion of the nut (40). In an embodiment, the first drive shaft (12) is an extended drive shaft.
Further, the second drive shaft (22) of the vacuum pump (20) is secured to the slot (42). In an embodiment, the second drive shaft (22) is an extended drive shaft. The first drive shaft (12) and the second drive shaft (22) are secured to the nut (40) such that the first drive shaft (12) and the second drive shaft (22) are facing each other.
The second drive shaft (22) is provided with a drive lug (not shown) adapted to secure the slot (42). Further, a front cover (60) is provided for covering the nut (40) and sprocket wheel (30).
The nut (40) torque is high enough to sustain the drive torque of vacuum pump (20). Further, increasing size of the nut (40) increases the frictional area. Therefore, the thread friction of the nut (40) is not increased beyond pre-defined

limits. This is achieved by putting a spring washer (14) between the nut (40) and the sprocket wheel (30) as shown in figure 2.
Further, concentricity of the slot (42) of the nut (60) is maintained, so that alignment of the drive lug of the vacuum pump (20) and the high pressure pump (10) axis is maintained. This avoids undue stress on the first drive shaft (12) and the second drive shaft (22) of the high pressure pump (10) and the vacuum pump (20) respectively. The first drive shaft (12) along with the nut (60) receives the drive from the sprocket wheel (30) and simultaneously transmit power to the vacuum pump (20).
During the operation, upon rotating the sprocket wheel (30) by the drive from the engine of the automobile, the high pressure pump (10) and the vacuum pump (20) starts rotating. As the high pressure pump (10) and the vacuum pump (20) are positioned opposite to each other, and have opposite rotating orientation. The high pressure pump (10) rotates in clock-wise direction, and the vacuum pump (20) rotates in anti-clock-wise direction
The mechanism (100) of the present invention has an advantage of providing positive drive to the vacuum pump (20), Further, the mechanism (100) enables easy serviceability and accessibility. Furthermore, the mechanism (100) is easy to manufacture and robust in construction, which is capable of avoiding leakage from face of the vacuum pump (20). An O-ring is provided to the vacuum pump (20), which is driven by overhead camshaft installed in split housing. Circularity required for O-ring joint is difficult to maintain in split joint due to bore distortion. In this case it is put in front cover bore acting as single housing.
The first and the second drive shafts (12 & 22) integration with the nut (40) is very cost effective solution, because it doesn't add any parts in a drive mechanism. Further, lubrication to the vacuum pump (20) is through oil gallery integrated in the front cover (60), which avoids extended oil supply pipes. This

helps in leading reducing number of parts like pipe, banjo, banjo bolts, washer and the like.
By taking collar friction in to consideration, the present invention can take 15 to 20% of total torque for driving accessories, provided the joint is designed to standard torque value and elongations and materials used are as per standard.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the spirit or scope of the present invention.

We Claim
1. A mechanism for operating a vacuum pump and a high pressure pump using drive from engine of an automobile, the high pressure pump comprising a first drive shaft for mounting a sprocket wheel thereon, and the vacuum pump comprising a second drive shaft, the high pressure pump and the vacuum pump having opposite rotating orientation, characterized in that, the mechanism comprises,
a nut having an internally threaded portion and a slot configured on one end thereof, wherein the first drive shaft of the high pressure pump is secured to the to the internally threaded portion, and the second drive shaft of the vacuum pump is secured to the slot such that the first drive shaft and the second drive shaft are facing each other,
wherein upon rotating the sprocket wheel by the drive from the engine, the high pressure pump rotates in clock-wise direction and the vacuum pump rotates in anti-clock-wise direction.
2. The mechanism as claimed in claim 1, wherein the second drive shaft is provided with a drive lug adapted to secure the slot,
3. The mechanism as claimed in claim 1, wherein a spring washer is provided between the nut and the sprocket wheel.
4. The mechanism as claimed in claim 1, wherein a cover is provided for covering the nut and sprocket wheel.