FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION Clutch Bleeding Tool
APPLICANTS
TATA MOTORS LIMITED,
an Indian company
having its registered office at Bombay House,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
INVENTOR
Mr. Chetan S Chawadimani
An Indian National
of TATA MOTORS LIMITED,
an Indian company having its registered office
at Bombay House, 24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it
is to be performed.

Field of invention
This invention relates to clutch oil bleeding tool to remove air entrapped in hydraulic system.
Background of the invention
For all kind of passenger car and commercial vehicles, there is requirement of clutch oil bleeding equipment to remove the air entrapped inside the hydraulic system and pipelines. This is very much important to have proper functioning of clutch mechanism. Due to air entrapped inside hydraulic system, the clutch operation is ineffective. There are two ways by which air can be removed as follows,
a) Manual oil bleeding.
b) Power oil bleeding.
Power bleeding process is very fast & used in production processes where we require fast response. In case of field failures, customer may not have power bleeding machine. Also clutch slave cylinder packaging demands simple tool which will take care of manual oil bleeding. The existing manual oil bleeding process involves loosening of bleeding screw by ring spanner and then does the clutch pedal pressing and again tightening it. The process is as follows,
a) Fill the oil in the clutch fluid bottle.
b) Press the clutch pedal to extreme position
c) Loosen the clutch bleeding screw by ring spanner
d) Hydraulic oil along with air will come out with force
e) Then tighten it by ring spanner in same state
f) Then release clutch pedal
g) Follow the same process repeatedly.
This existing process is having following disadvantages,

a) Oil spills over the area and makes the area dirty.
b) Many times there is very less access to the clutch bleeding screw to loosen by normal ring spanner due to different packaging of aggregates.
Summary of the invention:
The main Object of the present invention is to provide a clutch bleeding tool with
integrated drainage path.
Another object of the present invention is to provide a clutch bleeding tool which
avoids spillage of oil during oil and air mixture removal.
Yet another object of the present invention is to solve the problem of packing
constraint during loosening of bleeding nipple and develop good tool accessibility.
Yet another object of the present invention is to simplify the process of clutch oil
bleeding on vehicle.
The above objectives are achieved by developing special tool. The tool comprises of hollow tubular spanner with across flat on one side equivalent to size of bleeding nipple across flat (Hex portion provided on nipple for tightening & loosening). The other side of tubular spanner is having square drive to use ratchet. The tool is developed in such a manner that it has a central slot provided on it. Through this slot a flexible hose is integrated inside which extend to outside of the tool. The outside diameter of hose and inside diameter of tubular spanner in middle portion is kept same. The flexible hose is glued inside the tubular spanner. Also at front portion of tube where the flexible hose is rested, have internal groves are provided for holding the hose in fixed state. The flexible hose is positioned in such a way that it is just close to hex portion of the bleeding nipple during bleeding operation. The flexible hose is designed in such a way that the hose inner diameter is slightly less than outside diameter of bleeding nipple. This will ensure that hose is properly rolled over nipple tip (outside diameter) and hydraulically seals the surface. The whole mechanism acts as a special tool for clutch bleeding operation. The tool seats on bleeding screw provided on clutch slave cylinder and because of specific

dimensions of hose inner diameter, there is hydraulic sealing achieved between bleeding screw and hose. During clutch oil bleeding operation the front tip of the tool has to be properly positioned and start the bleeding operation to remove air entrapped inside hydraulic pipes. The oil coming out from the bleeding screw is directly transferred to the hose provided on tool and can be collected in separate bin thereby avoiding any splash of oil during clutch bleeding exercise and shop floor area remains clean and neat without a single drop of oil. This process ensures that safe and correct clutch oil bleeding.
According to present invention a clutch bleeding tool comprising, a tubular spanner with at least one open end for receiving a bleeding nipple and at least one lateral opening, a flexible hose integrated in said spanner, one end of said hose is positioned inside the spanner near the bleeding nipple receiving portion of said spanner and other end is extended outside the spanner through said lateral opening.
Brief description of the drawings:
Figure 1 shows the partial cross sectional view of complete arrangement of clutch
bleeding tool with the bleeding nipple.
Figure 2 shows the details of integrated tubular spanner with hose.
Figure 3 shows the details of tubular spanner.
Detailed description of the invention:
Referring to the figure 1, 2 and 3 the clutch slave cylinder (1) having a clutch bleeding nipple (2) with Hex portion for tightening. A tubular spanner (3) with a hose (4) integrated therein as shown. One portion of the hose (4) is positioned firmly inside special tubular spanner (3), and the other end is extended outside of the spanner (3) through a slot (7) (opening in lateral direction) provided at central portion of the tubular spanner. During bleeding operation the bleeding nipple end portion located inside the hose (4) and a hexagonal gap (5) is formed at the end of the tubular spanner with the hose (4) for locating the hexagonal portion of the

bleeding nipple (2). The flexible hose inner diameter is less than the outside diameter of the bleeding nipple. Also groves (6) are provided in tubular spanner to firmly hold the hose in position. Further the hose is glued to the spanner inner portion for firmly held in position. The one end (8) of tubular spanner (3) is flat to match with bleeding nipple and other end (8') having a square slot to drive using a ratchet. The outside diameter of the hose and inside diameter of tubular spanner at middle portion is kept same. This will ensure that hose is properly roller over nipple tip and hydraulically seals the surface.
During clutch bleeding operation, the tubular spanner (3) with integrated hose (4) held on Clutch bleeding nipple (2) available on Clutch slave cylinder (1), in such a way that Hex portion of Clutch bleeding nipple (3) is matched inside tubular spanner (3) hex portion (5). The face of clutch bleeding nipple is rested on face of hose (4). This ensures proper sealing between the hose and bleeding nipple end portion. The slight interference between nipple end and hose will take care of hydraulic sealing. For starting Clutch bleeding operation, a square drive extension hand tool inserted inside square end (8') portion of the tubular spanner and turned, which loosen the bleeding nipple and oil start flowing through the nipple end portion through the hose. The other end of the hose is placed inside a container, which will collect hydraulic oil from the system. The process of loosening and tightening of bleeding nipple starts by turning the spanner and the oil directly collect inside the container. This will avoid any spillage of hydraulic oil from the arrangement.
Advantages
1. The process of clutch oil bleeding is simplified.
2. This tool ensures that there shall not be oil splashing during clutch bleeding operation as against traditional clutch oil bleeding process.
3. The process of clutch bleeding safe.
4. This tool can be used at places where accessibility is not very good. Hence can be used at places where there are packaging constraints at design stage.

5. If proper care is taken the oil coming from bleeding screw can be reused. This is very useful in case of small workshops where power oil bleeding machine is not available.
6. Instead of using open ended spanner, the tool uses ratchet hand tool with square drive, which has better control on tightening.
7. Because of usage of hex drive for bleeding screw, there shall fewer chances of damages of hex portion of bleeding screw.

We Claim,
1. A clutch bleeding tool comprising, a tubular spanner with at least one open end for receiving a bleeding nipple and at least one lateral opening, a flexible hose integrated in said spanner, one end of said hose is positioned inside said spanner near the bleeding nipple receiving portion of the spanner and other end is extended outside the spanner through said lateral opening.
2. A clutch bleeding tool as claimed in claim 1 wherein one end of said spanner having a provision for positioning said bleeding nipple.
3. A clutch bleeding tool as claimed in any one of the preceding claims wherein said bleeding nipple end portion located inside said hose.
4. A clutch bleeding tool as claimed in any one of the preceding claims wherein said hose inner diameter is less than the outside diameter of said bleeding nipple.
5. A clutch bleeding tool as claimed in any one of the preceding claims wherein grooves are provided on the spanner to hold the hose in position.
6. A clutch bleeding tool as claimed in any one of the preceding claims wherein said hose is glued to the spanner inner wall for holding it in position.
7. A clutch bleeding tool as claimed in claim 2 wherein other end of said spanner having a slot for driving using a ratchet.
8. A clutch bleeding tool substantially as herein described with reference to accompanying drawings