DESC:Field of the invention

The present invention relates to coupling mechanisms for coupling an engine on to a test bed during testing and validation thereof, and more particularly to a coupling mechanism used in hot-testing of internal combustion engines.

Background of the invention

Testing is a process of identifying and evaluating performance of the system in the light of predefined parameters. Each and every industry uses different testing techniques to ensure the quality and performance. In automobile and mechanical industries, the engines are tested to check various critical performance parameters such as power, mechanical efficiency, specific fuel consumption, exhaust smoke, emission and the like. In general, the testing validates conformance to pre-decided standards or pre-decided values for the various performance parameters of engine so as to decide acceptability.

Generally, in engine manufacturing or production process, engines are subjected to hot testing with introduction of fuel, after its assembly. The object of hot testing is to test the engine for certain quality or do compliance in order to check critical performance parameters in confirmation with pre-decided standards so as to decide whether the engine is acceptable or fit for further use/ further fitment on to a vehicle.

The testing of the engines is generally performed by connecting them to test-beds which involves complex technical set up and high-cost equipments to measure various engine performance parameters accurately. The test beds are designed so as to reduce time wasted in non-operational or non-usage activities such as engine coupling or fitment to the test bed. The engines to be tested are connected to the testing bed or dynamometer of the test set up followed by firing of the engine to begin the testing process.

However, the engines run at high speed at high load conditions during testing. Hence, the coupling needs to be highly secure, safe and also strong enough to endure repeated cycles of operation or its usage for multiple engines being tested on the same test bed. One of the traditional ways of coupling the engine to the test bed involves bolting the adapter plate of the test bed to the engine. This process is time consuming though it ensures secure coupling.

There are few efforts seen in the art to reduce the time required for coupling the engine to the test bed using different types of coupling. For example, the Chinese patent no. CN 203705166U discloses a flywheel connection device for a miniature engine dynamometer wherein sliding blocks of one connecting element slide along the socket made on other connecting element to establish the coupling between different types of engines to be tested and test bench. Further, the United States patent no. US6405585 B1 discloses portable flywheel test assembly wherein the rings gear drivingly connects to the axle of flywheel to conduct testing of different engines. In addition, few coupling mechanisms in the art are described hereinafter-

As shown in FIG. 1, a coupling mechanism for an engine is depicted which connects the engine with test bed as per prior art or existing practice, wherein a flywheel adapter plate (2) coupled to a propeller shaft (3) of the test bed is connected with the flywheel (1) of the engine to be tested. In such coupling mechanisms, the engine has to be taken to the test bed and requires to be connected online or while the test bed remains idle. Accordingly, during engine testing, the engine is coupled to the dynamometer through a flywheel adapter plate and propeller shaft. The flywheel adapter plate is mounted on the flywheel with the help of bolts. However, while doing this activity the operator has to bend, lift the flywheel with hand and align all the bolts and tighten the same with spanner. This activity takes nearly seven minutes of online time as per existing practices.

Referring to FIG. 2, an improvement of the coupling mechanism for an engine that connects the engine with the test bed is shown, wherein the adapter plate female part of spline joint (4) and male part of spline joint (5) engage with each other, without any inter-locking mechanism. Such coupling mechanisms reduce engine testing online time wherein spline coupling in-between the flywheel adapter plate and propeller shaft thereby reducing the online time from seven minutes to three seconds. However, during testing of this embodiment with partial improvement still has drawbacks and is unsafe in terms of a chance of engine toppling from the engine testing trolley during testing as the joint is a kind of free/ unsecured/ unlocked joint. Also, the life of the coupling is prone to be less with relative movements.

Moreover, the prior art coupling mechanisms add considerable idle time for coupling the engines to the testing facility although the existing practices provide a secure coupling. This eventually affects throughput or operating efficiency in accordance with the type of equipment and tester.

Accordingly, there exists a need of a coupling mechanism for coupling an engine to a test bed at a hot-testing facility that eliminates all the drawbacks of the prior art.

Summary of the invention

The present invention provides a simple and effective coupling mechanism for an engine to facilitate coupling thereof to a test bed at a hot testing facility. The coupling mechanism of the present invention connects the engine with the test bed using a slpine shaft male-female arrangement that comprises a male coupling part and a female coupling part.

The male coupling part includes a sleeve that has a spring connected thereto. The female coupling part includes a plurality of inner splines, a retainer ring, a locking ball bearing, and an outer sleeve. Each of the inner splines has a groove that facilitates a locking arrangement with the locking ball bearing. The coupling mechanism includes an adapter plate fitted on a flywheel of the engine that includes a quick release coupling connected thereto.

The coupling mechanism includes a pedal mechanism for supporting coupling weight during coupling process. The pedal mechanism includes a manually operable pedal and a support to rest the coupling portion thereon.

Brief Description of Drawings

FIG. 1 depicts a coupling mechanism for an engine in accordance with the prior art;
FIG. 2 depicts an embodiment in accordance with the prior art deploying part of the coupling mechanism of the present invention;
FIG. 3 shows a male coupling part of the coupling mechanism of the present invention;
FIG. 4 shows a female coupling part of the coupling mechanism of the present invention;
FIG. 5 depicts the male showing details of splines of a male shaft;
FIG. 6 depicts a manual pedal operated mechanism adapted for the coupling mechanism of the present invention;
FIG. 7 shows a pedal mechanism of the coupling mechanism in operation for supporting the coupling portion;
FIG. 8 shows the pedal mechanism of the coupling mechanism of FIG. 7;
FIG. 9 depicts the coupling mechanism of the present invention with QRC on an adapter Plate mounted on engine side in operation for being aligned with a test bed side having spline shaft;
FIG. 10 depicts the coupling mechanism of the present invention in a connected or coupled position with the test bed side;
FIG. 11 depicts the coupling mechanism of the present invention with an engine side view;
FIG. 12 depicts the coupling mechanism of the present invention in an initial position during coupling or connection process;
FIG. 13 depicts the coupling mechanism of the present invention in a connected position;
FIG. 14 depicts the coupling mechanism of the present invention having engine sleeve details in a slid position;
FIG. 15 depicts the coupling mechanism of the present invention having engine sleeve details in a released position;
FIG. 16 depicts the coupling mechanism of the present invention in a coupled or engaged position; and
FIG. 17 depicts the coupling mechanism of the present invention wherein the coupling is being engaged with sliding of the sleeve before engagement.

Detailed Description of Drawings

Although specific terms are used in the following description for sake of clarity, these terms are intended to refer only to particular structure of the invention selected for illustration in the drawings, and are not intended to define or limit the scope of the invention.

References in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.

Referring to FIGS. 3 and 4, a coupling mechanism according to a preferred embodiment of the present invention is shown that is adapted for coupling an engine to a test bed at a hot-testing facility with a splined male-female coupling joint as shown.

As shown in FIG. 3, the coupling mechanism includes a male coupling part (6). The male coupling part (6) is mountable with an adapter plate (6A) that is adapted to be fitted on a flywheel (6B) of an engine. The adapter plate (6A) has a quick release coupling (QRC, hereinafter) that is separate from a propeller shaft of the test bed. The male coupling part (6) includes a sleeve (7) in order to facilitate quick sliding while coupling the engine to the test bed. The sleeve (7) has a spring connected thereto. The spring facilitates the sleeve (7) to return to its normal position after sliding action thereof.

As shown in FIG. 4, the coupling mechanism includes a female coupling part (8). The female coupling part (8) includes a retainer ring or retainer circlip (9) that retains the position of the sleeve (7) during a locking action thereof. The female coupling part (8) includes a locking ball bearing (10) that locks the female coupling part (8) on the male coupling part (6) such that an outer sleeve (11) of the female coupling part (8) slides over and returns with spring action as it includes a spring mechanism therein. The female coupling part (8) includes a groove preferably defined along an outer diameter with a locking arrangement. The groove is provided on the splines for proper seating of the locking ball bearing on the splines.

In accordance with the present invention, the coupling mechanism includes six spline couplings with integral QRC in order to provide rigidity and safety. This helps distribution of the torsional load bearing on the splines of the male part equally on the six splines thus reducing wear of the splines, also making the joint more rigid and to avoid toppling of the engine during testing.

As shown in FIGS. 5-6, splines (12) on the male part in accordance with the present invention is described above. The coupling mechanism for an engine according to an embodiment of the invention includes a manual pedal operated mechanism (14) for supporting the coupling portion for convenience of the operator or to obviate carrying of the weight/ load of the coupling by the operator during the coupling activity that is while connecting the engine with a test bed (13).

Referring to FIGS. 7-17, in operation, the coupling mechanism of the present invention is duly tested on production test bed and time study of the changed process is also carried out. Accordingly, it is observed that the online time of this activity is observed to be reduced from 7 minutes to 3 seconds or less than 10 seconds even considering other operator-related / operational factors.

In the context of the present invention, the pedal mechanism assists in supporting the coupling for convenience of operator or to obviate carrying of the weight/ load of the coupling by the operator during the coupling activity / connecting engine with the test bed wherein the QRC on the adapter plate mounted on engine side is aligned with the test bed side having spline shaft in order to couple or connect the engine with the test bed side.

Accordingly, initial and final positions of the coupling mechanism of the present invention during coupling or connection process are illustrated. However, it is understood that the sleeve attains a slid position during the coupling process and subsequently attains the released position after completing the coupling process.

Advantages of the present invention
1) The coupling mechanism of the present invention facilitates a safe coupling means for an engine thereby using quick release couplings.
2) The coupling mechanism of the present invention provides uses a spline shaft arrangement with splines in specific quantity in order to provide strength and secured coupling/ connection.
3) The coupling mechanism of the present invention provides a medium for connecting the engine with test bed advantageously reduces idle time for the test bed.
4) The coupling mechanism of the present invention advantageously allows connection of the engine with test bed quickly and effortlessly by the operator.
5) The coupling mechanism of the present invention connects the engine with test bed with least manual efforts to the operator.
6) The coupling mechanism of the present invention connects the engine with test bed that can be readily implemented to any existing test beds, preferably at hot testing facility for IC engines, without needing any major modifications/ work/ cost of modification in existing setups.
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.
,CLAIMS:
1) A coupling mechanism for connecting an engine with a test bed, the coupling mechanism comprising:
a male coupling part positioned with a sleeve, the sleeve having a spring connected thereto;
a female coupling part having a plurality of inner splines defined along an interior thereof, the inner splines respectively having a groove, the groove facilitating a locking arrangement with the male coupling part thereby having the sleeve slid thereon, the female coupling part having a retainer ring, a locking ball bearing, and an outer sleeve connected thereto;
an adapter plate connected to a flywheel, the adapter plate having a quick release coupling connected thereto; and
a pedal mechanism having a manually operable pedal and a support, the support holding the male and female coupling parts thereon.

2) The coupling mechanism as claimed in claim 1, wherein the spring facilitates the sleeve to return to a normal position after sliding action thereof.

3) The coupling mechanism as claimed in claim 1, wherein the retainer ring retains the position of the sleeve during a locking action thereof.

4) The coupling mechanism as claimed in claim 1, wherein the groove forms a seating that locks the locking ball bearing on the splines.

5) The coupling mechanism as claimed in claim 1, wherein the locking ball bearing locks the female coupling part on the male coupling part during a locking action thereof.