DESC:FORM 2
The Patent Act 1970
(39 of 1970)
&
The Patent Rules, 2005

COMPLETE SPECIFICATION
(SEE SECTION 10 AND RULE 13)

TITLE OF THE INVENTION

“A TOOL FOR TESTING BUSH QUALITY”

APPLICANT:

Name Nationality Address
Mahindra & Mahindra Limited Indian Mahindra & Mahindra Ltd.,
MRV, Mahindra World City (MWC),
Plot No. 41/1, Anjur Post, Chengalpattu,
Kanchipuram District – 603004 (TN) INDIA

The following specification particularly describes and ascertains the nature of this invention and the manner in which it is to be performed:-

TECHNICAL FIELD
[001] The embodiments herein generally relate to testing of bush in a housing and more particularly, but not exclusively to testing of bush in a housing using a tool by determination of slip torque of the bush.

BACKGROUND
[002] Generally, a bush is a member in housing to provide a bearing surface for a rotary shaft. The bush supports the rotary shaft and may also provide lubrication to the rotary shaft. In order for the smooth performance of the shaft, the bonding between the bush and the bore in the housing must be firm, otherwise the bush may slip and tend to rotate along with the shaft. Bush failure i.e rotation of bush along with the shaft is one of the major problems in engines.
[003] Bush failure in areas like internal combustion engines may lead to excessive vibration, noise and even failure of crucial engine components and housing. Bush failure occurs due to variation in dimensions and material of the bush supplied by the bush manufacturers. Therefore, it is necessary for the OEM (original equipment manufacturers) to test the quality of the bush supplied by the bush manufacturer.
[004] Conventionally, a bush’s quality is tested by the OEM using push out load test in which a hydraulic ram coupled with a load cell is pressed against the bush provided in the component to push the bush out of the bore of the component and the load required to push the bush out of the bore is measured. The measured load value is compared with the predetermined limits specified by the bush manufacturer to determine the bush quality. The push out load test is an approximate method of testing the bush quality as it does not measure the load required to slip the bush. The push out load test requires a dedicated set of special machines for testing the bush. Further, the cost of the machines used for testing and the time required for testing is high. Furthermore, the push out load test requires skilled labors for testing.
[005] Therefore, there exists a need for a simple and cost-effective tool and a method for testing a bush. Furthermore, there exists a need for a tool that can eliminate the aforementioned drawbacks.

OBJECTS
[006] The principal object of an embodiment of this invention is to provide a simple and a cost-effective tool for testing a bush mounted in a component.
[007] Another object of an embodiment of this invention is to provide a tool for determining a slip torque of a bush mounted in a component.
[008] The objects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF DRAWINGS
[009] This invention is illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0010] FIG. 1 depicts an exploded view of a tool, according to an embodiment of the invention as disclosed herein;
[0011] FIG. 2 depicts a perspective view of the tool according to an embodiment of the invention as disclosed herein;
[0012] FIG. 3 depicts a perspective view of the tool assembled with a bush provided in a component, according to an embodiment of the invention as disclosed herein;
[0013] FIG. 4 depicts a cross sectional view of the tool assembled with the bush provided in the component, according to an embodiment of the invention as disclosed herein; and
[0014] FIG. 5 depicts a perspective view of the tool according to an embodiment of the invention as disclosed herein.

DETAILED DESCRIPTION
[0015] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed 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.
[0016] The embodiments herein achieve a simple and cost-effective tool simple and a cost-effective tool for testing a bush mounted in a component. Further, embodiments herein achieve a tool for determining a slip torque of a bush mounted in a component. Referring now to the drawings, and more particularly to FIGS. 1 through 5, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0017] FIG. 1 depicts an exploded view of a tool according to an embodiment of the invention as disclosed herein. The tool 100 includes a housing 102, a releasing element 104, a spring 106 and a locking element 108. The tool assembly 100 is used for testing the quality of the bush 200 mounted in a component 300.
[0018] FIG. 2 depicts a perspective view of the tool according to an embodiment of the invention as disclosed herein. In an embodiment, the housing 102 is used for receiving or holding the releasing element 104, spring 106, and locking element 108. In an embodiment, the housing 102 includes a first opening 102a, a second opening 102b and a means 102c for receiving a device (not shown) adapted to rotatably drive the tool 100. In an embodiment, the first opening 102a of the housing 102 is used for receiving the releasing element 104. In an embodiment, the second opening 102b of the housing 102 is used for receiving the spring 106 and the locking element 108. The second opening 102b is provided in fluid communication with the first opening 102a thereby enabling the releasing element 104 to support the spring 106 and to release the locking element 108. In an embodiment the means 102c for receiving a device adapted to rotatably drive the tool 100 is a protruding member. In another embodiment, the means 102c for receiving a device adapted to rotatably drive the tool 100 is an opening (not shown).
[0019] In an embodiment, the device adapted to rotatably drive the tool 100 is used for rotatably driving the tool 100 assembled with the bush 200 thereby providing load/torque to the bush 200 through the tool 100 and for measuring the load/torque required to slip the bush 200 for testing the quality of the bush 200. In an embodiment, the device adapted to rotatably drive the tool 100 is a manual digital torque wrench. However, it is also within the scope of the invention to provide a torque sensor, torque analyzer, hydraulic or pneumatic or a manual torque wrench as the device adapted to rotatably drive the tool 100. In an embodiment the manual digital torque wrench is used for providing the load/torque to the bush 200 and for measuring the slip torque of the bush 200.
[0020] In an embodiment, the releasing element 104 is used for supporting the spring 106 and for releasing the locking element 108 from the bush 200 after testing, thereby releasing the tool 100 from the bush 200. In an embodiment, the releasing element 104 is a shaft having circular cross section. However, it is also within the scope of the invention to provide the shaft with any other cross section as the releasing element 104 without otherwise deterring the intended function of the releasing element 104 as can be deduced from the description. The releasing element 104 is received by the first opening 102a of the housing 102. As the releasing element 104 supports the spring 106 through the second opening 102b, removal of the releasing element 104 from the first opening 102a releases the locking element 108 from the bush 200, since the spring 106 supporting and loading the locking element 108 is unsupported.
[0021] In an embodiment, the spring 106 is used for loading the locking element 108 against the bush 200 to enable the locking element 108 to lock with the bush 200. The spring 106 pushes the locking element 108 against an opening (not shown) in the inner periphery of the bush 200 for locking the locking element 108 with the bush 200.
[0022] FIG. 4 depicts a cross sectional view of the tool assembled with the bush provided in the component, according to an embodiment of the invention as disclosed herein. In an embodiment, the locking element 108 is used for locking the tool 100 with the bush 200. The locking element 108 includes a top end 108a and a bottom end 108b. The bottom end 108b of the locking element 108 is received by the second opening 102b and is seated on top of the spring 106 and the top end 108a of the locking element 108 is received by the opening (not shown) of the bush 200. In an embodiment, the locking element 108 is a shaft having a circular cross section. However, it is also within the scope of the invention to provide a shaft having any other cross section as the locking element 108 without otherwise deterring the intended function of the locking element 108 as can be deduced from the description. The locking element 108 by locking the tool 100 with the bush 200 transmits the load/torque received by the tool 100 from the device adapted to rotatably drive the tool 100 to the bush 200.
[0023] FIG. 3 depicts a perspective view of the tool assembled with a bush provided in a component, according to an embodiment of the invention as disclosed herein. FIG. 5 depicts a perspective view of the tool according to an embodiment of the invention as disclosed herein. The bush 200 is tested using the tool 100 as follows. First, the releasing element 104 is assembled in the first opening 102a of the housing 102. Thereafter, the spring 106, followed by the locking element 108 is assembled inside the second opening 102b of the housing 102. Thereafter, the assembled tool 100 is assembled inside the bush 200 provided in the component 300 such that the top end 108a of the locking element 108 is held/locked in the opening (not shown) of the bush 200. Thereafter, the means 102c for receiving a device adapted to rotatably drive the tool 100 is assembled with the device (not shown) adapted to rotatably drive the tool 100. Therafter, the user provides the load/torque to the tool 100 through the device (not shown) adapted to rotatably drive the tool 100. Since the tool 100 is locked/assembled with the bush 200 through the locking element 108, when the user provides the load/torque to the tool 100 through the device (not shown) adapted to rotatably drive the tool 100, the load/torque is transmitted to the bush 200 and the bush 200 slips/rotates along with the tool 100 at a certain level of load/torque. The slip torque of the bush 200 is determined and compared with a predetermined slip torque values for measuring the quality of the bush 200. In an embodiment the device (not shown) adapted to rotatably drive the tool 100 is the manual digital torque wrench (not shown) from which the slip torque of the bush 200 is determined.
[0024] Once, the slip torque of the bush 200 is determined, the tool 100 is removed from the bush 200 as follows. First, the releasing element 104 is removed from the first opening 102a of the housing 102. The removal of the releasing element 104 results in the release of the locking element 108 from the bush 200. Thereafter, the housing 102 of the tool 100 is removed from the bush 200. Thus the tool 100 is removed from the bush 200.
[0025] A comparison between the results obtained using a CAE (computer aided engineering) simulation software for determining the bush quality by measuring the torque required to slip the bush 200 and the actual test results made using the tool 100 for determining the quality of the bush 200 is shown in the below table.
S.No Material combination between bush 200 and component 300 Interference Slip torque obtained through
CAE Simulation
(Nm) Slip torque obtained through test made using tool
(Nm)
1 Steel-Tin-CI Min 238 310
2 Steel-Tin-CI Max 356 330

[0026] From the aforementioned table it is clearly evident that the test carried using the tool 100 is accurate in determining the bush quality.
[0027] 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 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.

CLAIMS
We claim,
1. A tool for determining a slip torque of a bush in a component, the tool comprising:
a locking element adapted to lock the bush with the tool;
a spring adapted for loading the locking element to facilitate the locking element to lock the bush;
a releasing element adapted to release the locking element from the bush; and
a housing having a first opening adapted to receive the releasing element; a second opening adapted to receive the spring and the locking element; and a means for receiving a device adapted to rotatably drive the tool,
wherein
the first opening and the second opening are provided in fluid communication with each other; and
the tool transmits a torque to the bush through the locking pin on rotatably driving the tool by the device adapted to rotatably drive the tool to determine the slip torque of the bush.
2. The tool as claimed in claim 1, wherein the locking element is received by an opening in the bush to lock the bush with the tool.
3. The tool as claimed in claim 1, wherein the locking element includes a top end and a bottom end.
4. The tool as claimed in claim 1, wherein the locking element is a shaft having circular cross section.
5. The tool as claimed in claim 1, wherein the releasing element is a shaft having circular cross section.
6. The tool as claimed in claim 1, wherein the means for receiving a device adapted to rotatably drive the tool is a protruding member.
7. The tool as claimed in claim 1, wherein the means for receiving a device adapted to rotatably drive the tool is an opening.
8. The tool as claimed in claim 1, wherein the device adapted to rotatably drive the tool is at least one of manual digital torque wrench, torque sensor, torque analyzer, hydraulic torque wrench, pneumatic torque wrench, and manual torque wrench.

Date: 11th March, 2016 Signature:
Dr.Kalyan Chakravarthy

ABSTRACT
A tool for testing a bush quality includes, a locking element to lock the bush with the tool, a spring for loading the locking element to facilitate the locking element to lock the bush, a releasing element to release the locking element from the bush and a housing having a first opening to receive the releasing element; a second opening to receive the spring and the locking element and a means for receiving a device adapted to rotatably drive the tool. The tool transmits a torque to the bush through the locking pin on rotatably driving the tool by the device adapted to rotatably drive the tool to determine the slip torque of the bush.
.Fig. 5

,CLAIMS:CLAIMS
We claim,
1. A tool for determining a slip torque of a bush in a component, the tool comprising:
a locking element adapted to lock the bush with the tool;
a spring adapted for loading the locking element to facilitate the locking element to lock the bush;
a releasing element adapted to release the locking element from the bush; and
a housing having a first opening adapted to receive the releasing element; a second opening adapted to receive the spring and the locking element; and a means for receiving a device adapted to rotatably drive the tool,
wherein
the first opening and the second opening are provided in fluid communication with each other; and
the tool transmits a torque to the bush through the locking pin on rotatably driving the tool by the device adapted to rotatably drive the tool to determine the slip torque of the bush.
2. The tool as claimed in claim 1, wherein the locking element is received by an opening in the bush to lock the bush with the tool.
3. The tool as claimed in claim 1, wherein the locking element includes a top end and a bottom end.
4. The tool as claimed in claim 1, wherein the locking element is a shaft having circular cross section.
5. The tool as claimed in claim 1, wherein the releasing element is a shaft having circular cross section.
6. The tool as claimed in claim 1, wherein the means for receiving a device adapted to rotatably drive the tool is a protruding member.
7. The tool as claimed in claim 1, wherein the means for receiving a device adapted to rotatably drive the tool is an opening.
8. The tool as claimed in claim 1, wherein the device adapted to rotatably drive the tool is at least one of manual digital torque wrench, torque sensor, torque analyzer, hydraulic torque wrench, pneumatic torque wrench, and manual torque wrench.