METHODS AND APPARATUS FOR MEASURING IMPACT TOUGHNESS OF A TIE ROD END
A method is provided for measuring impact toughness of a tie rod end through use of a pendulum-type impact testing machine. The method includes attaching a first member of the tie rod end with respect to a base of the pendulum-type impact testing machine. The pendulum-type impact testing machine is operated such that the hammer impacts the second member of the tie rod end. Force arising from the impact of the hammer upon the second member of the tie rod end is measured. A support apparatus is also provided for supporting the tie rod end in a position to receive contact from the hammer of the pendulum-type impact testing machine.
The present invention relates to methods and apparatus for measuring the impact toughness of a tie rod end through use of a pendulum-type impact testing machine.
BACKGROUND OF THE INVENTIONTie rod ends are often employed as components of vehicles and other equipment. In one particular application, a tie rod end is employed as part of a vehicle's suspension system to facilitate attachment of a vehicle's tie rod to a wheel spindle or king pin of the vehicle. An example of a conventional tie rod end 10 is depicted in
In many applications, such as when used in vehicular steering systems, tie rod ends are subjected to significant impact loading. Accordingly, when selecting a tie rod end for use with a particular piece of equipment (e.g., an automobile or all terrain vehicle), it is important that a tie rod end of adequate toughness is selected. If a tie rod end of inadequate toughness is selected, the tie rod end can be prone to premature failure, thereby resulting in catastrophic failure of the associated equipment. However, conventional methods and apparatuses do not allow for adequate testing of tie rod ends to ensure their ability to exhibit a predetermined amount of impact toughness. As such, there is a need for improved methods and apparatus which can be easily and inexpensively employed to facilitate impact testing of a tie rod end.
SUMMARY OF THE INVENTIONIn accordance with one embodiment of the present invention, a method is provided for measuring impact toughness of a tie rod end through use of a pendulum-type impact testing machine. The method comprises providing a tie rod end having a first member and a second member which are pivotally attached together. A pendulum-type impact testing machine having a base and a hammer is also provided. The hammer is configured for pivotable movement with respect to the base. The first member of the tie rod end is attached with respect to the base of the pendulum-type impact testing machine. The pendulum-type impact testing machine is operated such that the hammer impacts the second member of the tie rod end. Force arising from the impact of the hammer upon the second member of the tie rod end is measured.
In accordance with another embodiment of the present invention, a method is provided for measuring impact toughness of a tie rod end. The method comprises providing a pendulum-type impact testing machine having a base, a hammer, and a measurement apparatus. The hammer is configured for pivotable movement with respect to the base, about a pivot axis, and over an arc defining a first plane. The measurement apparatus is configured to measure force arising from impact of the hammer upon an object secured with respect to the base. A tie rod end is provided which has a first member and a second member. The first member comprises a threaded end and at least a portion of a pivot ball joint opposite the threaded end. A proximal end of the second member interfaces said pivot ball joint such that a distal end of the second member is pivotable between limit positions with respect to the threaded end of the first member. A support apparatus is attached to the base of the pendulum-type impact testing machine. The threaded end of the tie rod end is attached to the support apparatus such that the distal end reaches one of the limit positions in which a longitudinal axis of the second member lies within a second plane perpendicular with the first plane and parallel with or including the pivot axis of the hammer. The pendulum-type impact testing machine is operated such that the hammer impacts the second member substantially perpendicularly to the longitudinal axis of the second member. Force arising from the impact is measured through use of the measurement apparatus.
In accordance with yet another embodiment of the present invention, a support apparatus is configured for supporting a tie rod end in a position to receive contact from a hammer of a pendulum-type impact testing machine. The support apparatus comprises a mounting structure and a support structure. The mounting structure has a bottom surface and at least one mounting provision. The mounting provision is configured to facilitate securement of the mounting structure such that the bottom surface contacts a base of a pendulum-type impact testing machine. The bottom surface lies substantially within a first plane. The support structure is attached to the mounting structure and is inclined with respect to the first plane. The support structure is configured to receive attachment of a first member of a tie rod end such that a second member of the tie rod end is movable into a limit position in which a longitudinal axis of the second member is perpendicular with the first plane.
While the specification concludes with claims particularly pointing out and distinctly claiming the present invention, it is believed that the same will be better understood from the following description taken in conjunction with the accompanying drawings in which:
Embodiments of the present invention and its operation are hereinafter described in detail in connection with the views and examples of
In accordance with one embodiment of the present invention, a support apparatus and method are provided and configured for supporting a tie rod end in a position to receive contact from a hammer of a pendulum-type impact testing machine. The support apparatus can be formed or constructed in any of a variety of specific configurations provided that, however, the support apparatus is configured for supporting a tie rod end in a position to receive contact from a hammer of a pendulum-type impact testing machine. By way of example, a support apparatus 50 in accordance with one particular embodiment of the present invention is hereafter described in connection with
The support apparatus 50 includes a mounting structure 54 and a support structure 58. The mounting structure 54 is configured for attachment to a base (e.g., 32 in
In one particular embodiment, as shown generally in
The support apparatus 50 is also shown to include a wedge-shaped intermediate member 66 for use in attaching the mounting structure 54 to the support structure 58. While the intermediate member 66 is shown to be formed from solid plate material, it will be appreciated that an intermediate member can be formed in any of a variety of alternative configurations, and/or that a support apparatus can be formed without an intermediate member. The support apparatus 50 can be formed from any of a variety of suitable materials such as metal, plastic, fiberglass, composites, or some other material or combination thereof which has sufficient strength to secure a tie rod end with respect to a base of a pendulum-type impact testing machine as described herein.
Referring again to
The bore 64 can be configured to interface a first member of a tie rod end. In one particular embodiment, to facilitate attachment of a first member of a tie rod end to a support apparatus, at least one bolt can be inserted through a bore in the support apparatus and can then be threaded into a threaded end of the first member of the tie rod end. For example, as shown generally in
In accordance with certain embodiments of the present invention, the head 44 of the hammer 34 of the pendulum-type impact testing machine 30 can be provided with an impact tip which is configured to focus the energy of the hammer 34 for selective impact upon a predetermined area of the second member 14 of the tie rod end 10. In one embodiment of the present invention, the impact tip can be attached to the hammer 34 of the pendulum-type impact testing machine 30. For example, an angled member 36 can be attached to the head 44 of the hammer 34, as shown in
Once the support apparatus 50 is attached to the base 32 of the pendulum-type impact testing machine 30, and the first member 12 of the tie rod end 10 is attached to the support apparatus 50, it will be appreciated that the support apparatus 50 can rigidly and immovably support the first member 12 of the tie rod end 10 with respect to the base 32 of the pendulum-type impact testing machine 30. To prepare for impact from the hammer 34, the second member 14 can be moved such that it reaches the limit position in which the longitudinal axis L2 of the second member 14 (1) lies within a second plane P2 which is both perpendicular with the first plane P1 and is parallel with the pivot axis A1 of the hammer 34 (as shown in the embodiment of
For clarification, the distal end 22 of the second member 14 of the tie rod end 10 is movable into multiple limit positions. A limit position, as used herein, refers to an end-of-travel position in which further pivoting of the second member 14 with respect to the first member 12 in a particular direction is impeded by the inherent construction of the tie rod end 10. An angle of tie rod end deflection (D1 shown in
As shown in the embodiment of
As shown in
Methods and apparatus in accordance with the teachings of the present invention can be useful for measuring the performance of tie rod ends when they are exposed to varying forces. In addition, such methods and apparatus can also be used to assess the impact of environmental conditions upon a tie rod end. For example, in one particular embodiment, the temperature of a tie rod end can be adjusted (e.g., by heating or cooling) to a predetermined temperature prior to operating the pendulum-type impact testing machine. This testing can be repeated at different predetermined temperatures as desired. Other environmental characteristics might additionally or alternatively be varied prior to testing a tie rod end such as, for example, exposure of the tie rod end to chemicals (e.g., road salt), sunlight, humidity, moisture, and/or radiation, for example. In this manner, and through such testing, the performance (e.g., toughness) of a tie rod end can effectively be predicted and verified.
The foregoing description of embodiments and examples of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or limit the invention to the forms described. Numerous modifications are possible in light of the above teachings. Some of those modifications have been discussed, and others will be understood by those skilled in the art. The embodiments were chosen and described in order to best illustrate the principles of the invention and various embodiments as are suited to the particular use contemplated. It is hereby intended that the scope of the invention be defined by the claims appended hereto.
Claims
1. A method for measuring impact toughness of a tie rod end through use of a pendulum-type impact testing machine, the method comprising:
- providing a tie rod end having a first member and a second member which are pivotally attached together;
- providing a pendulum-type impact testing machine having a base and a hammer, wherein the hammer is configured for pivotable movement with respect to the base;
- attaching the first member of the tie rod end with respect to the base of the pendulum-type impact testing machine;
- operating the pendulum-type impact testing machine such that the hammer impacts the second member of the tie rod end; and
- measuring force arising from the impact of the hammer upon the second member of the tie rod end.
2. The method of claim 1 further comprising adjusting the temperature of the tie rod end to a predetermined temperature prior to operating the pendulum-type impact testing machine.
3. The method of claim 1 wherein the first member has a threaded end and an opposite end disposed along a first longitudinal axis, the second member has a proximal end and a distal end disposed along a second longitudinal axis, the opposite end and the proximal end are pivotally attached such that the second member is pivotable between limit positions with respect to the threaded end, the hammer is configured for pivotable movement about a pivot axis and over an arc defining a first plane, and the threaded end of the first member is attached with respect to the base such that the second member is movable into one of said limit positions in which the second longitudinal axis lies within a second plane, the second plane being perpendicular with the first plane and being parallel with or including the pivot axis of the hammer.
4. The method of claim 3 wherein the hammer impacts the second member substantially perpendicularly to the second longitudinal axis.
5. The method of claim 3 wherein the first member of the tie rod end is attached with respect to the base of the pendulum-type impact testing machine by attaching the threaded end of the first member to a support apparatus, and attaching the support apparatus to the base.
6. The method of claim 5 wherein the support apparatus is attached to the base of the pendulum-type impact testing machine by fasteners.
7. The method of claim 5 wherein the attachment of the threaded end of the first member to the support apparatus comprises threading at least one bolt into the threaded end.
8. The method of claim 5 wherein the first longitudinal axis is inclined with respect to the base when the threaded end of the first member is attached to the support apparatus.
9. The method of claim 8 wherein the first longitudinal axis lies within or parallel with the first plane when the threaded end of the first member is attached to the support apparatus.
10. The method of claim 9 wherein the base is substantially planar with a third plane and the third plane is perpendicular to each of the first plane and the second plane.
11. The method of claim 1 further comprising attaching an impact tip to the hammer of the pendulum-type impact testing machine, wherein the impact tip is configured to selectively impact a predetermined area of the second member of the tie rod end.
12. A method for measuring impact toughness of a tie rod end, the method comprising:
- providing a pendulum-type impact testing machine having a base, a hammer, and a measurement apparatus, wherein the hammer is configured for pivotable movement with respect to the base, about a pivot axis, and over an arc defining a first plane, and the measurement apparatus is configured to measure force arising from impact of the hammer upon an object secured with respect to the base;
- providing a tie rod end having a first member and a second member, the first member comprising a threaded end and at least a portion of a pivot ball joint opposite the threaded end, a proximal end of the second member interfacing said pivot ball joint such that a distal end of the second member is pivotable between limit positions with respect to the threaded end of the first member;
- attaching a support apparatus to the base of the pendulum-type impact testing machine;
- attaching the threaded end of the tie rod end to the support apparatus such that the distal end reaches one of the limit positions in which a longitudinal axis of the second member lies within a second plane perpendicular with the first plane and parallel with or including the pivot axis of the hammer;
- operating the pendulum-type impact testing machine such that the hammer impacts the second member substantially perpendicularly to the longitudinal axis of the second member; and
- measuring force arising from the impact through use of the measurement apparatus.
13. The method of claim 12 wherein the support apparatus is attached to the base of the pendulum-type impact testing machine by fasteners.
14. The method of claim 12 wherein the threaded end of the tie rod end is attached to the support apparatus by threading at least one bolt into the threaded end.
15. The method of claim 12 further comprising adjusting the temperature of the tie rod end to a predetermined temperature prior to operating the pendulum-type impact testing machine.
16. The method of claim 12 wherein the longitudinal axis of the first member is both inclined with respect to the base and lies within or parallel with the first plane when the threaded end of the first member is attached to the support apparatus, and wherein the base is substantially planar with a third plane and the third plane is perpendicular to each of the first plane and the second plane.
17. The method of claim 12 further comprising attaching an impact tip to the hammer of the pendulum-type impact testing machine, wherein the impact tip is configured to selectively impact a predetermined area of the second member of the tie rod end.
18. A support apparatus configured for supporting a tie rod end in a position to receive contact from a hammer of a pendulum-type impact testing machine, the support apparatus comprising:
- a mounting structure having a bottom surface and at least one mounting provision, the mounting provision configured to facilitate securement of the mounting structure such that the bottom surface contacts a base of a pendulum-type impact testing machine, wherein the bottom surface lies substantially within a first plane; and
- a support structure attached to the mounting structure and being inclined with respect to the first plane, wherein the support structure is configured to receive attachment of a first member of a tie rod end such that a second member of the tie rod end is movable into a limit position in which a longitudinal axis of the second member is perpendicular with the first plane.
19. The support apparatus of claim 18 being configured to rigidly and immovably support the first member of the tie rod end with respect to the base of the pendulum-type impact testing machine.
20. The support apparatus of claim 19 wherein the support structure is provided with an aperture configured to receive a threaded end of the first member of the tie rod end.
21. The support apparatus of claim 19 further comprising a cylindrical sleeve having a centrally and longitudinally extending bore configured to interface the first member of the tie rod end.
22. The support apparatus of claim 19 wherein the support structure is configured to support the first member of the tie rod end such that the hammer of the pendulum-type impact testing machine impacts the second member of the tie rod end substantially perpendicularly to the longitudinal axis of the second member of the tie rod end.
23. A pendulum-type impact testing machine comprising the support structure of claim 18.
Type: Application
Filed: Nov 3, 2006
Publication Date: May 8, 2008
Inventor: Timothy A. Abke (Zanesfield, OH)
Application Number: 11/592,626