FORM-2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2006
COMPLETE
Specification
(See Section 10 and Rule 13)
A TORSION TESTING APPARATUS FOR A TEST ELEMENT
ENDURANCE TECHNOLOGIES PRIVATE LTD.,
an Indian Company,
of B 1/3 Chakan Industrial Area, Village Noghoje, Taluka Khed,
Dist. Pune -410501, Maharashtra, INDIA
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

FIELD OF THE DISCLOSURE
The present disclosure relates to a torsion testing apparatus for determining maximum load carrying capacity of small mechanical components.
BACKGROUND
Mechanical components are required to be tested for measuring the failure load of the components. Failure load determines the load at which the component fails or the load carrying capacity of the component. Various tests are performed on the mechanical components which include bending test, compression test, shear test and torsional test. In case of torsion test, torsional loading is applied on the load carrying members in order to determine the maximum torsion-load carrying capacity or failure load and failure mode of the various torsion load carrying members such as suspension components. However, in certain cases, the load carrying members are of smaller size, accordingly it becomes difficult to apply torsional load on the actual component and hence the small component is tested with bending load to simplify the test. However, the method of indirectly determining torsional load carrying capacity of the specimen by applying bending load, inaccurately determines the actual failure load or failure mode. For example, determining the torsional load carrying capacity for a brake stopper which is used on the chassis of a motorcycle, the torsional failure load is simulated by applying a vertical bending load. However, such simulations do not represent the actual load applied during the braking event and the failure mode.

The torsional testing is very critical for small components, such as, a brake stopper or similar components, henceforth referred to as "test element" in the present disclosure, for measuring the effect of manufacturing variability on the failure load and in turn determining the safety factor in design. Accordingly, there was felt a need for an apparatus in order to accurately determine the torsional load carrying capacity of the test element.
OBJECTS
Some of the objects of the present disclosure aimed to ameliorate one or more problems of the prior art or to at least provide a useful alternative are described herein below.
An object of the present invention is to accurately determine the torsional load carrying capacity of a test element.
Another object of the present invention is to provide an apparatus that is capable of measuring the failure load for a test element under torsional load.
Yet another object of the present invention is to provide an apparatus that facilitates application of torsional load in both clockwise as well as anticlockwise directions for determining the failure load.
Still another object of the present invention is to provide an apparatus that remains fully engaged with the test element.
Another object of the present disclosure is to provide an apparatus that applies torsional moment, until the failure of the test element during the testing.

SUMMARY
In accordance with the present invention there is provided a torsion testing apparatus for applying torsional force on a test element, the apparatus comprising:
> fixture elements having a predetermined shape being provided with a slot for engaging the test element to the apparatus, the fixture elements adapted to be angularly displaceable about a pivot point;
> a hydraulic arrangement cooperating with the fixture elements through a ball and socket joint, the hydraulic arrangement adapted to apply torsional force on the test element through the fixture elements alternatively in clockwise direction or anti-clockwise direction; and
> a load cell located between the hydraulic arrangement and the ball joint, the load cell being adapted to measure the torsional force.
Typically, the predetermined shape of the fixture elements is dependent on the direction of application of the torsional force.
Typically, the fixture elements have a lever arm and at least one load carrying arm.
Typically, the pivot point is located eccentric to the ball and socket joint for applying torsional force on the test element.
Typically, the ball and socket joint is in an engaged configuration during deformation of the test element.

Typically, the ball and socket joint is in a disengaged configuration on failure of the test element.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
The torsion testing apparatus for applying torsional force on a test element of the present disclosure will now be described with the help of accompanying drawings, in which:
Figure 1 illustrates a test apparatus for application of vertical bending force on a test element;
Figure 2 illustrates a fixture and an arrangement for applying a clockwise torsional load on a test element in accordance with the present invention;
Figure 3 illustrates details of a ball and socket joint of the arrangement shown in Figure 2;
Figure 4 illustrates a fixture and an arrangement used for applying an anticlockwise torsional load on a small sized test element;
Figure 5 illustrates details of a ball and socket joint of the arrangement shown in Figure 4;
DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS
A preferred embodiment of the torsion testing apparatus for applying torsional force on a test element of the present disclosure will now be

described in detail with reference to the accompanying drawings. The preferred embodiment does not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.
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 following 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.

Figure 1 illustrates a test apparatus (1) having a pivot point (2) for application of vertical bending force (3) on a test element (10). The failure load of the test element (10), when subjected to vertical bending force (3) with the fixture (4) applied by the test apparatus (1), does not simulate the actual loading condition to which the test element (10) is subject to during actual operation of the test element (10).
The present disclosure is directed towards a torsion testing apparatus (100) for applying torsional force on a test element, shown in figure 1 and figure 3, for application of torsional force on a test element (10), thereby enabling accurate determination of torsional force carrying capacity of the test element (10).
The apparatus (100), shown in figure 2 and figure 4, comprises at least one fixture element (12), a ball and socket joint (22), a load cell (34) and a hydraulic arrangement (32).
The fixture element (12) has a predetermined shape, as illustrated in figure 3 and figure 5, depending on the direction of application of the torsional force, that is, clock wise or anti-clockwise. The fixture element (12) has at least one load carrying arm (16) extending from a first side of a lever arm (18) which is perpendicular to the parallel arms. The load carrying arm (16) defines a slot (20). One end of the lever arm (18) is free and is adapted to locate the ball and socket joint (22). The fixture element (12) is provided with a through hole on the lever arm (18) so as to allow a pivot rod (24) to pass through the fixture element (12) such that the pivot rod (24) is fixed on either end to columns (26 and 27) fixed on a platform (28) provided to support the apparatus (100). The pivot rod (24) forms a pivot point (30)

about which the fixture element (12) is angularly displaceable. The fixture element (12) engages and supports the test element (10) during the torsion
test.
The ball and socket joint (22) is located on the first side of the lever arm (18) or on a second side of the lever arm (18) located opposite the first side depending on the clockwise or anti-clockwise direction of the torsional force. The pivot point (30) is positioned eccentric to the ball and socket joint (22) for effective application of the torsional force. The ball and socket joint (22) is in an engaged configuration during deformation of the test element (10) and in a disengaged configuration during failure of the test element (10) depending on the direction of the torsional force and the location of the ball and socket joint (22) on the lever arm (18).
The hydraulic arrangement (32) is engaged with the fixture element (12) through the ball and socket joint (22). The hydraulic arrangement (32) enables in applying torsional force on the test element (10) through the fixture element (12) in the clockwise direction or in the anticlockwise direction. The load cell (34) cooperates with the hydraulic arrangement (32) and the ball and socket joint (22) and helps in measuring the torsional force applied on the test element (10). The lever arm (18) located between the force application point at the ball and socket joint (22) and pivot point (30) along with the force applied through the hydraulic arrangement (32) results in a torsion force on the test element (10).
Torsional force is applied in the clockwise direction or in the anti-clockwise direction, that is, along the direction of arrow 1 or along the arrow 2 respectively. Due to eccentricity of the ball and the socket joint (22) and the

pivot point (18), the ball and socket joint (22) are in the engaged configuration during the application of the torsional force. The torsional force acting on the ball and the socket joint (22) creates a torsional moment on the test element (10) in the clockwise direction and the anticlockwise direction depending on the direction of application of the torsional force. As the hydraulic arrangement (32) applies force on the load cell (34) and ultimately to the test element (10) via the ball and socket joint (22), the force is measured by the load cell (34). The test element (10) undergoes deformation due to the torsional force acting on the test element (10).
During the deformation of the test element (10), the ball slide in the socket of the ball and socket joint (22) and maintains constant torsional moment until the failure of the test element (10). The torsional force is applied on the test element (10) until the failure of the test element (10). After the failure of the test element (10), the ball and socket joint (22) disengages, thus, preventing any pre-load on the test element (10) during torsional testing.
The support condition for the test element (10) is variable depending on the engagement of the test element (10) on the slot (20) provided on the fixture element (12).
TEST RESULTS
Table 1 provided below shows the test data for failure load in Kilo Newton (KN) of 6 test elements of the same type by the application of torsional force in the clockwise direction and the anticlockwise direction on the torsion testing apparatus, in accordance with the present invention.

Table 1
Sr.
No. Failure Load (KN)

Clockwise direction of torsional force Anticlockwise direction of torsional force
1 35.11 34.02
2 35.55 33.99
3 35.68 33.86
4 36.07 33.69
5 35.25 33.06
The test elements used in conducting the trail are brake stopper provided on a swing arm of a vehicle. The test was conducted on 6 brake stoppers. It was noted that there was a variation in the maximum load carrying capacity or the failure load of the brake stoppers. This variation in the failure load of the swing arm with the brake stopper is due to the geometry of the brake stopper during the clockwise and anticlockwise direction of application of the torsional force. The failure load of the break stopper ranges from 35.11 KN to 35.25 KN during application of torsional force in the clockwise direction while the failure load ranges from 34.02 KN to 33.06 KN during application of torsional force in the anti-clockwise direction. The failure load on each of the brake stoppers indicates the simulation of the actual on road braking conditions in the test environment, thus enabling testing of the brake stoppers without involving the vehicle. The torsional moment acting on the brake stopper is calculated by multiplying the torsional force applied on the brake stopper by the length of the lever arm of the fixture element; the length of the lever arm being fixed for a particular test apparatus.

Table 2 provided below shows the test data for the failure load in Kilo Newton (KN) of a plurality of brake stoppers provided on the swing arm when subjected to vertical bending force instead of a torsional force. The highest value 54 KN and the lowest value 50 KN of the failure load of the brake stoppers when subjected to vertical bending load are substantially higher than the failure load of the brake stoppers when subjected to torsional force as shown in Table 1.
Table 2

Sr. No. Failure Load (KN)
1 54
2 50
On comparing the results of table 1 and table 2, it is evident that it is critical to apply torsional force on the brake stoppers of vehicle instead of vertical bending force. This is because the application of torsional force enables in simulating the on-road braking condition of the brake stopper provided on the swing arm.
TECHNICAL ADVANTAGES
The technical advancements offered by the present disclosure include the realization of:
> varying the magnitude of the load, angle of the load and pivot location
> accurate determination of torsional force carrying capacity and failure load of a test element.

> applying of torsional load in both clockwise as well as anti-clockwise directions for determining the failure load for test element.
> finding variability of the failure load verses the acceptance load limit in order to estimate the safety margin.
Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
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.
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.
While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the disclosure. These and other changes in the preferred embodiment 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.

We Claim:
1. A torsion testing apparatus for applying torsional foree on a test element,
said apparatus comprising:
> fixture elements having a predetermined shape being provided with a slot for engaging the test element to said apparatus, said fixture elements adapted to be angularly displaceable about a pivot point;
> a hydraulic arrangement cooperating with said fixture elements through a ball and socket joint, said hydraulic arrangement adapted to apply torsional force on said test element through said fixture elements alternatively in clockwise direction or anti-clockwise direction; and
> a load cell located between said hydraulic arrangement and said ball and socket joint, said load cell being adapted to measure said torsional force.

2. The apparatus as claimed in claim 1, wherein the predetermined shape of said fixture elements is dependent on the direction of application of said torsional force.
3. The apparatus as claimed in claim 1, wherein said fixture elements has a lever arm and at least one load carrying arm.

4. The apparatus as claimed in claim 1, wherein said pivot point is located
eccentric to said ball and socket joint for applying torsional force on the
test element.
5. The apparatus as claimed in claim 1, wherein said ball and socket joint is adapted to be in an engaged configuration during deformation of the test element.
6. The apparatus as claimed in claim 1, wherein said ball and socket joint is adapted to be in a disengaged configuration on failure of the test element.