A TEST EQUIPMENT

Technical Field

The present invention relates to a test equipment for performing a fatigue test by ensuring that dynamic conditions of axons, which are included in the front suspension systems of vehicles, changing on thereof are simulated triaxially.

Background of the Invention

An axon part is a part which is used in the wheel assembly of the front suspension system, that is a sub-part of the chassis system of the vehicles, and which bears the brake disc, hub, ABS sensor, wishbone, damper (shock absorber) and axle shaft. Axon is one of the most important supporting parts of the suspension system. An axon part is manufactured by means of steel forging method so as to be durable in heavy commercial vehicles, whereas it is manufactured by means of iron casting or aluminum casting method in passenger vehicles.

An axon, whose design has been completed and which is aimed to be produced, is subjected to virtual and physical tests before starting mass production and in the event that it passes the tests, it gets mass production permission. Tests of component, system and vehicle level are included among the tests applied to the axon part. Since system and vehicle level tests are expensive tests, it is aimed to increase the reliability level by testing the safety of the axon design via component tests. Since the axons are exposed to loads on the x-axis when the vehicle brakes during drive, on the y-axis when cornering and on the z-axis when it passes over potholes and bumps while driving on the road, the axon design must be subjected to fatigue tests. Today, when a fatigue testing is performed on an axon, the fixtures included in the test equipment are kept simple and the number of pistons is kept at a minimum level and therefore, the fatigue value is obtained with separate fixtures and tests as a result of the load received from each axis. In other words, an axon is subjected to the load values received from the x-axis for a specified number of cycles at first and then the same test piece is tested with a piston positioned on the y-axis and a fixture designed specially for it. Finally, the test piece -which is subjected to forces separately in both x and y axis- is positioned on the z axis and the testing process is terminated by testing it with a special fixture. Since the loads reach the axon part at the same time -not one by one- during drive, the current test equipment does not allow the axon design to be tested with a real simulation. Therefore, today there is a need for test equipment which will enable to perform a fatigue test by allowing the force received from all three axes to be applied at the same time.

The Chinese utility model document no. CN205808734U, an application included in the state of the art, discloses a test bench which enables to perform a real road test by simulating the forces applied to the vehicle suspension system vertically, horizontally and longitudinally. In the said utility model, it is enabled to test the rigidity and fatigue performances of a suspension system in three direction. In the said utility model, it is enabled to perform a reliable rigidity and fatigue test on the suspension system on all three axes by ensuring that the hydraulic systems -which are used in response to the suspension system placed on the test bench- are positioned correctly.

The Chinese utility model document no. CN103411780, an application included in the state of the art, discloses a method for performing fatigue and durability simulation in wheel hubs of automobiles. In the method used in the said invention, it is enabled to calculate the force to be applied on the hub depending on the vehicle parameters and to control the force to be applied on the hub. In the invention, it is provided to simulate the hub fatigue and durability according to actual vehicle force by ensuring that the force to be applied on the hub is applied so as to be equal to the weight of the automobile in operating state. In the invention, it is provided to apply the force -which is previously requested to be applied- on the hub by means of hydraulic pistons of the said test equipment and to perform a real simulation, by fixing the test equipment while the fatigue simulation of a hub is carried out.

Summary of the Invention

An objective of the present invention is to realize a test equipment for performing a fatigue test by ensuring that axons, which are included in the front suspension systems, are simulated triaxially as is the case with the changing dynamic conditions of a vehicle.

Another objective of the present invention is to realize a test equipment which comprises three different load application pistons to simulate axons triaxially as is the case with the changing dynamic conditions and enables to observe the physical changes occurring in the part after the number of cycles to be applied by each piston.

Another objective of the present invention is to realize a test equipment which enables to perform crack control by means of a penetrant liquid in order to determine whether there is any microcrack on the part being subjected to a test.

Another objective of the present invention is to realize a test equipment which enables to complete a test in a shorter time and with less cost by way of applying loads to the same part from three different axes at the same time.

Detailed Description of the Invention “A Test Equipment” realized to fulfil the objectives of the present invention is shown in the figure attached, in which:

Figure l is a perspective view of the inventive test equipment.

The components illustrated in the figure are individually numbered, where the numbers refer to the following:

1. Test equipment

2. Fixing fixture

3. X piston

4. X axis fixture

5. Y piston

6. Y axis fixture

7. Z piston

8. Z axis fixture

9. Joint connection

10. Control unit

A: Axon

The inventive test equipment (1) for performing a fatigue test by ensuring that axons (A), which are included in the front suspension systems, are simulated triaxially as is the case with the changing dynamic conditions of a vehicle comprises at least one fixing fixture (2) which is located at least on one ground and situated in a position almost perpendicular to the ground; at least one X piston (3) which enables to apply brake load to the axon (A) aimed to be tested and which is connected to the fixing fixture (2) by means of a X axis fixture (4); at least one Y piston (5) which enables to apply cornering load to the axon (A) aimed to be tested and which is connected to the fixing fixture (2) by means of a Y axis fixture (6); at least one Z piston (7) which enables to apply pothole and/or bump load to the axon (A) aimed to be tested and which is connected to the fixing fixture (2) by means of a Z axis fixture (8); at least one joint connection (9) which enables to constitute a limited movable structure such as the level of the vehicle where the axon (A) is located and which is located on the fixing fixture (2); at least one control unit (10) which is configured to ensure that load is applied to the axon (A) part at the same time up to the predetermined number of cycles to the X piston (3), the Y piston (5) and the Z piston (7).

In the inventive test equipment (1), the fixing fixture (2) enables to fix the axon (A) part in order to apply force on three axes simultaneously by means of pistons. The fixing fixture (2) has a plurality of joint connections (9) comprising ball joint at the connection points in order to represent the load condition of vehicle level at maximum level.

In the inventive test equipment (1), the X piston (3) applies the loads, that are received on the x axis up to the number of cycles predetermined in the control unit (10), onto the axon (A) simultaneously with the Y and Z pistons (5,7). The X piston (3) is connected with a X axis fixture (4) so as to be fixed to the fixing fixture (2).

In the inventive test equipment (1), the Y piston (5) applies the cornering loads, that are received on the Y axis up to the number of cycles predetermined in the control unit (10), to the axon (A) simultaneously with the X and Z pistons (3,7). The Y piston (5) is connected with a Y axis fixture (6) so as to be fixed to the fixing fixture (2). In the inventive test equipment (1), the Z piston (7) applies the pothole and/or bump loads, that are received on the Z axis up to the number of cycles predetermined in the control unit (10), to the axon (A) simultaneously with the X and Z pistons (3,7). The Z piston (7) is connected with a Y axis fixture (8) so as to be fixed to the fixing fixture (2).

The inventive test equipment (1) can apply fatigue loads onto the axon (A) at the same time on three axes. The control unit (10) controls the X, Y and Z pistons (3,5,7) and then provides the load onto the axon (A) up to the number of predetermined cycles. The inventive test equipment (1) whereby loads received from three different axes are tested at the same time in the dynamic conditions of the vehicle plays a decision-making role in determining whether the mass production of the axon (A) will be started or not. The inventive test equipment (1) enables to perform the fatigue test of a part in jig tests by single installation quickly and in a cost effective way. A penetrant liquid can be applied in order to determine whether there is any microcrack on the part being subjected to a test, upon the axon (A) part is tested. Thereby, the crack control can be performed visually.

Within these basic concepts; it is possible to develop various embodiments of the inventive “Test Equipment (1)”; the invention cannot be limited to examples disclosed herein and it is essentially according to claims.