Patent ID: 12216093

DETAILED DESCRIPTION

According to aspects of the present disclosure, a material testing system that uses at least one hydraulic grip fixture is improved with cable clips that are attachable to a respective lateral side of each hydraulic grip wedge. Each cable clip has another end that extends to engage a cable extending from a corresponding wedge retention spring hole. The cable enables manual extension of a wedge retention spring for engagement and disengagement from the hydraulic grip wedge. The cable clip maintains the cable in a noninterfering position during operational use of the material testing system.

In one or more embodiments, the present innovation provides a convenient means of keeping cables out of the way of fingers and hands while a person is attempting to mount, un-mount or otherwise access a specimen being tested using the hydraulic wedge grips of a servohydraulic test machine. Today, the common method of restraining these wires is to use copious amounts of tape to tape the stiff wires out of the way. This is sometimes ineffective as the wires come loose from the tape, and it a wasteful use of tape.

FIG.1illustrates a disassembled view of a material handling system100having a load frame102that utilizes one or two hydraulic grips104attached respectively to upper and lower attachment fixtures105a-105b. One of the upper and lower attachment fixtures105a-105bcan omit gripping, such as using a pin and clevis system106attached to upper attachment fixture105a. The load frame102includes a base108having support feet109positioned on a support surface110. A pair of vertical columns112a-112bextend upwardly from a base housing113of the base108. A crosshead114is received for vertical movement on the pair of vertical columns112a-112band provides the upper attachment fixture105a. The base housing113encloses and supports a main actuator115that provides the lower attachment fixture105b. A pair of hydraulic linear actuators116a-116battached between the base108and the crosshead114to position the crosshead114for the length of a test specimen118. Crosshead114is then locked to vertical columns112a-112b. The hydraulic grip104receives one end of the test specimen118and that is positioned between and attached to one of: (i) the base108and the crosshead114. The hydraulic grip104includes a fixture body120having a wedge recess122. A pair of hydraulic grip wedges124are received in opposition within the wedge recess122. Each hydraulic grip wedge124are flexibly retained within the wedge recess122by wedge retention springs128that are extended by cables130. After the retention springs128are attached to a respective hydraulic grip wedge124, each cable130is held in positioned by a cable clip132.

FIG.2illustrates a perspective view of the hydraulic grip104. Each hydraulic grip wedge124has a pair of vertical wedge retention spring holes126out of which the cables130extend for manual extension of the wedge retention springs128(FIG.1). The cables130are maintained in a noninterfering position by cable clips132that attach to a respective lateral side134of one of the hydraulic grip wedges124. In one or more embodiments, the cable clips132engage spring retention bolts134.

FIG.3Ais a partially cutaway detail view of a hydraulic grip wedge124of the hydraulic grip104. One vertical wedge retention spring hole126is depicted in phantom. A wedge retention spring128is hooked to an attachment eye136mounted to a lower surface of the wedge recess122of the fixture body120of the hydraulic grip104. A spring retention bolt138is inserted through a horizontal spring retention hole140to engage a top end of the wedge retention spring128. The cable130is engaged to the other end respectively of each extension spring128and extends out of the corresponding hydraulic grip wedge124, enabling manual extension of the respective retention spring128. In particular, the cable130enables aligning the free end of the wedge retention spring128with the horizontal spring retention hole140so that the spring retention bolt138may be inserted.

FIG.3Bis a detail view of the hydraulic grip wedge124and the cable clip132of the hydraulic grip104. The hydraulic grip wedge124is allowed by the wedge retention spring128to move in and out of engagement with a test specimen118(FIG.1). The cables130are maintained in a noninterfering position by cable clips132that attach to a respective lateral side134of one of the hydraulic grip wedges124. The cable clips132are respectively attached at one end to a lateral side134of one of the pair of hydraulic grip wedges124and engaged at another end to a corresponding cable130to maintain the cable130in a noninterfering position. In one or more embodiments, the cable clip132resembles a bent combination wrench with partially open socket ends that end engaging to already installed bolt head142of the horizontal spring retention bolt138(FIG.3A) and cable130.

FIG.4Ais a perspective view of an example cable clip132.FIG.4Bis a top view of the example cable clip132.FIG.4Cis a side view of the example cable clip132.FIG.4Dis an end view of the example cable clip132. In one or more embodiments, the new clips provide a re-usable way to restrain these wires without using tape. The clip orientation can be adjusted, and the clip is reusable. The clips can be manufactured out of polymer material quickly using rapid prototyping (a3D printer). The clips can be flat and semi-rigid having a hole for retention by the existing spring retention screw with an identical hole in the other end for retaining the cable. Both holes have slots for sliding the cable into the hole for retention. Both holes are slotted so that the clip can be installed either with the slots toward the front or rear of the machine, which gives additional flexibility in the cable orientation once retained. The clip is bent slightly in the middle, which retains the cable in a direction away from the specimen, and also improves ease of inserting the cable in the slot. The clip is easily installed by one person during wedge installation. Two clips are used for each wedge, and therefore eight clips per installation (four for the two lower wedges and four for the two upper wedges). The clip is easily fabricated, light in weight, effective and very inexpensive.

In one or more embodiments, a cable clip132has two configurations: slots forward, slots aft. The configuration is easily changed and depends upon where the cable is to be retained. A cable clip132could be machined from metal sheet (aluminum, steel, etc.), or, as has been done to date, a cable clip132can be fabricated from polymer using a rapid prototyping machine (3D printer). A cable clip132could be made from most any material sufficiently stiff to withstand handling, retain the cable in place, and be resilient to withstanding the friction from the existing spring retention screw.

FIG.5presents a flow diagram of a method500of performing material testing with an improved hydraulic grip. The method500includes actuating a pair of hydraulic linear actuators that are attached between a base of the load frame that support the main actuator and the crosshead to position the crosshead to a selected vertical position on a pair of vertical columns attached to the base (block502). The selected vertical position corresponds to a length of the test specimen. Method500includes locking the crosshead to the pair of vertical columns at the selected vertical position prior to actuating the main actuator to materially test the test specimen (block504). The method500includes attaching a fixture body of a hydraulic grip to one of a lower attachment fixture atop a main actuator and an upper fixture attached to a crosshead of a load frame (block506). The method500includes attaching four wedge retention springs to a recess of the fixture body (block508). The method500includes passing respective one or more cables attached to each wedge retention spring through a corresponding vertical wedge retention spring hole in one of a pair of hydraulic grip wedges (block510). The method500includes, with a respective wedge retention spring extended in the wedge retention spring hole by manual actuation of a corresponding cable to align the free end of the spring with the wedge retention spring hole, the method500includes inserting a retention spring retention bolt through the spring end via a horizontal bolt hole that intersects the vertical wedge retention spring hole (block512). The method500includes attaching one end of a cable clip respectively to each lateral side of the pair of hydraulic grip wedges (block514). The method500includes engaging another end of the cable clip to a corresponding cable to maintain the cable in a noninterfering position (block516). The method500includes engaging a test specimen between the pair of hydraulic grip wedges (block518). The method500includes actuating the main actuator to materially test the test specimen (block520). Then method500ends.

For clarity, the material testing system is described herein as moving in a vertical direction, reducing the required footprint and enhancing access to each side of the test specimen and equipment. In one or more embodiments, aspects of the present innovation can be implemented in a horizontally oriented material testing system.

While the disclosure has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the disclosure. In addition, many modifications may be made to adapt a particular system, device or component thereof to the teachings of the disclosure without departing from the essential scope thereof. Therefore, it is intended that the disclosure not be limited to the particular embodiments disclosed for carrying out this disclosure, but that the disclosure will include all embodiments falling within the scope of the appended claims. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another.

In the preceding detailed description of exemplary embodiments of the disclosure, specific exemplary embodiments in which the disclosure may be practiced are described in sufficient detail to enable those skilled in the art to practice the disclosed embodiments. For example, specific details such as specific method orders, structures, elements, and connections have been presented herein. However, it is to be understood that the specific details presented need not be utilized to practice embodiments of the present disclosure. It is also to be understood that other embodiments may be utilized and that logical, architectural, programmatic, mechanical, electrical and other changes may be made without departing from general scope of the disclosure. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present disclosure is defined by the appended claims and equivalents thereof.

References within the specification to “one embodiment,” “an embodiment,” “embodiments”, or “one or more embodiments” are intended to indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. The appearance of such phrases in various places within the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Further, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not other embodiments.

It is understood that the use of specific component, device and/or parameter names and/or corresponding acronyms thereof, such as those of the executing utility, logic, and/or firmware described herein, are for example only and not meant to imply any limitations on the described embodiments. The embodiments may thus be described with different nomenclature and/or terminology utilized to describe the components, devices, parameters, methods and/or functions herein, without limitation. References to any specific protocol or proprietary name in describing one or more elements, features or concepts of the embodiments are provided solely as examples of one implementation, and such references do not limit the extension of the claimed embodiments to embodiments in which different element, feature, protocol, or concept names are utilized. Thus, each term utilized herein is to be given its broadest interpretation given the context in which that terms is utilized.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

The description of the present disclosure has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope of the disclosure. The described embodiments were chosen and described in order to best explain the principles of the disclosure and the practical application, and to enable others of ordinary skill in the art to understand the disclosure for various embodiments with various modifications as are suited to the particular use contemplated.