Patent Application
20140079523
The present disclosure relates to laminate structures and more particularly to the laminate structure used in a linkage member for a machine.
Pin joints in a linkage member may be used to connect the linkage member to different components of a machine. For example, U.S. Pat. No. 5,316,709 relates to manufacturing a dipper stick having a box shaped structure including an outer casing member. The outer casing member is formed of a high strength polymeric composite material. An inner filler comprising polyurethane foam is disposed inside the outer casing member in order to be integrated with the outer casing member. A plurality of bushing holders made of polymeric composite material are disposed at respective connecting portions of the box shaped structure in order to be integrated with the box shaped structure.
In one aspect of the present disclosure, a laminate structure is provided. The laminate structure includes a plurality of laminate layers. The laminate structure also includes a joint interface. The joint interface includes a retention member at least partially disposed between any two of the plurality of laminate layers. Further, the retention member has an opening for receiving a pin retaining member. The retention member is configured to provide a surface for transitioning the pin retaining member to the laminate structure.
Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.
Further, the machine 100 may include a linkage member such as a boom 110 which is pivotally mounted on the body 104. The boom 110 may extend outwards. A hydraulic cylinder 114 (or a pair of cylinders), controlled by an operator sitting in an operator cab 116 or by a machine control system, may move the boom 110 relative to the body 104 during operation.
Also, a stick 118 may be pivotally mounted at a pivot point 120 to an outer end of the boom 110. Similarly, a hydraulic cylinder 122 may be used to move the stick 118 relative to the boom 110 about the pivot point 120 during excavation. Further, a bucket 124 may be pivotally mounted at a pivot point 126 to an outer end of the stick 118. A hydraulic cylinder 128 may move the bucket 124 relative to the stick 118 about the pivot 126 during the operation.
A person of ordinary skill in the art will appreciate that the laminate structure 302 may include a plurality of laminate layers 401 (see
Further, in another embodiment, an inner surface of the pin retaining member 404 may include threads (not shown in figures). The threads may be configured to mate with corresponding threads of a bolt. In another embodiment, a sleeve (not shown in figures) may be provided between the retention member 402 and the pin retaining member 404. The sleeve may be made of metal. It should be noted that the sleeve may be provided in order to control press-fit forces during assembly.
An outer diameter of the retention member 402 may have a variety of shapes. In one embodiment, as shown in
Referring to
As against using box beam or tubular structures, an alternative laminate solid type construction may be used in the manufacture of the linkage member, for example, like the stick 118, the boom 110, and/or the bucket 124 of the machine 100. The laminate structure 302 disclosed herein may be made of the self reinforced polymers. The self reinforced polymer may have a lower modulus than traditional laminates. These laminate structures 302 may be relatively thicker in order to increase a potential load bearing surface at the any of the joint interface 202 A-C. However, due to the low modulus of the laminate structure 302, the laminate structure 302 may be more susceptible to yielding of the joint. More specifically, it may be difficult to create a relatively good interface between the plurality of laminate layers 401 and the pin retaining member 404.
In the present disclosure the retention member 402 may be interleaved between the plurality of laminate layers 401. The arrangement of the plurality of the retention members 402 may provide the surface for the transitioning of the metallic pin retaining member 404 to the non-metallic plurality of laminate layers 401 at the any of the joint interfaces 202 A-C in such a way that may be favorable from a stress and loading standpoint.
An exemplary method of manufacturing the laminate structure 302 having the retention member 402 will now be described. Initially, at least one section 702 of the laminate structure 302 including the plurality of laminate layers 401 may be placed on either side of a locating fixture. The locating fixture may typically have a cylindrical shape. Thereafter, the retention member 402 may be placed between the any two of the plurality of laminate layers 401. More specifically, the retention member 402 may be placed proximal to the any of the joint interfaces 202 A-C. The above procedure may be repeated until a stack or layup of the plurality of laminate layers 401 of a desired thickness is formed. It should be noted that each of the sections 702 may include consolidated sections of the plurality of laminate layers 401 made up of the polymer or composite materials.
Further, the layup of the plurality of laminate layers 401 and the plurality of retention members 402 may be consolidated at a pre-determined temperature. It should be noted that standard autoclaving processes, hydroclaving processes, press-consolidation or combination of any other similar such methods known in the art may be used for final consolidation of the structure. In one embodiment, the locating fixture may be removed and the pin retaining member 404 may be press fit into the laminate structure 302 after the final consolidation.
A person of ordinary skill in the art will appreciate that the method of manufacturing the laminate structure 302 described above is merely on an exemplary basis and does not limit the scope of this disclosure. Also, the stick 118 and the machine 100 described herein is exemplary. The present disclosure may also be utilized on numerous other components that require bolted joints or pinned interfaces. Additionally, the disclosure may be used in a variety of applications, especially if there is a need to provide the metallic pin joint in order to handle high loads in the application.
Although the embodiments of this disclosure as described herein may be incorporated without departing from the scope of the following claims, it will be apparent to those skilled in the art that various modifications and variations can be made. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.
