1. Field of the Invention
Embodiments of the present invention generally relate to a method and apparatus to facilitate adjustment or alignment of a joint or interface between two pieces of equipment, components, or portions of two pieces of equipment, parts, or components. More specifically, embodiments described herein relate to a filler material in the joint or interface to facilitate adjustment.
2. Description of the Related Art
Automated and non-automated equipment generally comprise a plurality of structural members, parts, or components coupled together to form a structure or framework suited for a particular use. The structure or framework may be configured to hold a part relative to a machine or tool, such as a jig or fixture, or the structure or framework may be configured to transfer a workpiece from on location to another, such as a pick-and-place device, among other workpiece transfer devices. Other equipment may include a structure or framework configured to support another structure, part, device, or mechanism.
The mechanism 100 generally includes a transfer means 105 coupled in a cantilevered fashion to a translational means 110, such as an actuation device or robotic device configured to move the transfer means 105 linearly and/or rotationally in the X, Y, and Z directions. The translational means 110 may be coupled to a base 129 to provide rigidity to the translational means 110 and stability to the transfer means 105 coupled thereto. The transfer means 105 includes a support member 115 and rod members 118 coupled thereto, which may include end effectors 120 configured to receive and support the workpiece 140. The transfer means 105 also includes a connecting member 125 coupled to the support member 115 that is adjustably coupled to a junction 140 at a joint, which is generally indicated at 150. The junction 140 may be a sleeve, a tubular member, a bracket, and the like, and may be coupled to an extended member 130 disposed on the translational means 110. In this example, the extended member 130 moves relative to a body 126 of the translational means 110 to facilitate moving the joint 150 and the transfer means 105 relative to the translational means 110 at least in the Z axis. For example, the extended member 130 may be coupled to an actuator within the body 126 of the translational means, such as a lead screw, and moves at least in the Z direction relative to the body 126.
The transfer means 105 typically includes couplings 112A-112D, such as coupling 112C and 112D between members 115 and 118, coupling 112B between member 115 and the connecting member 125, and coupling 112A between the junction 140 and the translational means 110. The couplings 112A-112D are typically a static coupling configured to prevent or minimize movement between the respective parts, and is typically designed and configured to maintain rigidity and position of the respective parts, as the respective parts may not require frequent or foreseeable adjustment. The couplings 112A-112D may be formed by a bond, for example, by welding, brazing, an adhesive, or other bond, which make movement between the respective parts difficult, if not impossible, without extensive downtime. Threaded connections and fasteners, such as bolts, screws, rivets, and the like may also be used to form the couplings 112A-112D.
The interface between the transfer means 105 and the translational means 110, which includes the joint 150, is configured to allow adjustment of the transfer means 105 relative to the translational means 110. Specifically, the connecting member 125 may selectively move in at least a portion of the six degrees of freedom, as shown in the inset at
The adjustment of the transfer means 105 may be accomplished by systematic loosening and tightening of the adjustment members 135, which is often a time-consuming task. However, during adjustment of the transfer means 105, tightening or loosening of one or more of the adjustment members 135 may often alter a previous adjustment. For example, tightening of one or more adjustment member(s) 135 may require loosening of one or more of the other adjustment member(s) 135, which may cause the orientation of the transfer means 105 to be altered or misaligned from the previous or desired adjustment. Therefore, the adjustment of the transfer means 105 to be statically positioned in the desired orientation may require multiple adjustments to, and manipulation of, the adjustment members 135, which may result in extensive downtime of the equipment as personnel tighten and loosen the adjustment members 135. Further, the transfer mechanism 100 or other equipment may be disposed in a housing or adjacent another structure that may make the junction 140 or joint 125 difficult to access by personnel. For example, the housing or other structure may have to be partially disassembled or moved to provide access to the junction 140, which may extend downtime of the equipment.
Therefore, there is a need for an adjustable joint that minimizes equipment downtime and facilitates easy adjustment by personnel.
The present invention generally describes a method and apparatus for adjusting or aligning two or more parts, elements, devices, or structures coupled together by an adjustable interface is described. The apparatus includes an adjustable joint at the interface, which includes a housing adapted to receive a portion of one of the two or more parts. The housing also includes a filler that is cycled between a liquid state and a solid state to facilitate adjustment and rigidity, respectively, between the portion of the two or more parts and the housing. The housing may include integral heating members to heat the filler. The method includes heating the filler to facilitate adjustment, adjusting the portion of the two or more parts, and cooling the filler.
In one embodiment, an adjustable joint is described. The adjustable joint includes a housing having an interior volume configured to receive at least a portion of a shaft, a heating means coupled to and in communication with at least a portion of the housing, and a eutectic filler material disposed in the housing that is cycled between a solid state and a liquid state, wherein the filler material has a melt-point range between about 110° F. and about 160° F.
In another embodiment, an adjustable interface between two or more structural components disposed on a piece of equipment is described. The adjustable interface includes a shaft coupled to at least one of the structural components, a housing having an interior volume configured to receive at least a portion of the shaft, the interior volume sized to permit axial, radial, rotational, and longitudinal movement to the shaft, a filler material disposed in the interior volume and in contact with the portion of the shaft disposed in the interior volume, and a flexible retention member coupled to a portion of the housing and the shaft, wherein the housing is configured to provide heat to the filler material.
In another embodiment, a method for adjusting an interface between two or more structural components disposed on a piece of equipment is described. The method includes providing a housing at the interface having an interior volume configured to receive at least a portion of one of the two or more structural components, wherein the structural component is in communication with a solid filler material disposed in the housing, heating the solid filler material to at or near a melt-point, adjusting the structural component in one or more of the six degrees of freedom, and cooling the filler material below the melt-point.
In another embodiment, a method for adjusting an interface between a first and second structural component is described. The method includes providing a housing at the interface having an interior volume configured to receive at least a portion of the first structural component and having a metallic filler material disposed therein, and cycling the metallic filler material between a liquid state and a solid state, wherein the first structural component may be moved relative to the second structural component when the filler is in a viscid, semi-viscid, or liquid state, and wherein the first structural component is fixed relative to the second structural component when the filler is in a solid state.
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
To facilitate understanding, identical reference numerals have been used, wherever possible, to designate identical elements that are common to the figures. It is also contemplated that elements disclosed in one embodiment may be beneficially utilized on other embodiments without specific recitation.
The present invention describes a method and apparatus for an adjustable joint or adjustable interface on a piece of equipment between two parts, structures, components, or elements that may move or require adjustment relative to each other. Embodiments described herein may be exemplarily described in reference to automated equipment, specifically a mechanism configured to support and transfer a semiconductor substrate, but the invention may be used on other equipment, parts, components, and devices as well. Examples include jigs, workpiece holding devices, and the like. Other examples include any equipment or components thereof having two or more parts or elements that may require periodic adjustment and/or alignment relative to each other, or one or more parts or elements that may require periodic adjustment and/or alignment relative to a workpiece.
The mechanism 200 generally includes a first structural component, such as a transfer means 105 coupled to a second structural component, such as a translational means 110. The translational means 110 may be an actuation device or robotic device configured to move the transfer means 105 linearly and/or rotationally in the X, Y, and Z directions similar to the transfer mechanism of
In this embodiment, the interface between translational means 110 and the transfer means 105 includes an adjustable joint 250, and the junction 140 of
In this embodiment, the connecting member 125 may be a shaft, a rod, a bar, a rigid wire or cable, or other structural element. The connecting member 125 may include a cross-section that is circular, tubular, rectangular, triangular, “H” shaped, “I” shaped, among other cross-sections. The connecting member 125 may be made of a metallic material, a ceramic material, a polymer, or any other material that is resistant to temperature fluctuations enabling the phase change of the filler 255 and provides sufficient mechanical integrity to the device, component, or part coupled thereto.
Unlike the junction 140 in
In this embodiment, the adjustable joint 250 includes the filler 255 that facilitates adjustment and/or alignment of the transfer means 105 relative to the translational means 110. The filler 255 is adapted to facilitate adjustment of the connecting member 125 by a phase change of the filler 255 between a solid and a liquid, for example between a solid state and a non-solid state, such as a viscid or semi-viscid state. The phase change to the viscid, semi-viscid, and/or liquid state may be provided by applying heat to the filler 255 and/or the joint housing 240. The phase change of the filler 255 permits movement of the connecting member 125 in a non-solid state, such as a liquid state and a viscid or semi-viscid state, and provides rigidity to the connecting member 125 in the solid state. The filler 255 may be a metal, such as an alloy, a polymer material, such as a thermoplastic, resins, or any material having a definitive melting point or melt-point range with sufficient mechanical properties suited for the particular application. In applications where the mechanical stress, or other mechanical properties and physical factors allow, the filler 255 may be a wax or wax composite, such as a blend of wax and reinforcing fibers, for example fiberglass fibers or carbon fibers, among others. In some embodiments, the filler 255 may be an electrorheological fluid or a magnetorheological fluid that may be cycled between varying degrees of viscosity to facilitate adjustment and/or alignment of the transfer means 105 relative to the translational means 110, and stability between the transfer means 105 and the translational means 110.
In one embodiment, the filler 255 is a eutectic mixture or eutectic alloy having a definitive transition temperature between a solid and liquid. Alternatively, the filler 255 may be a non-eutectic mixture or alloy having a transition temperature range between a solid and a liquid, and may include the viscid or semi-viscid state discussed above. In one embodiment, the filler 255 may have a melt-point or melt-point range higher than 212° F., such as between about 350° F. and below, such as between about 260° F. to about 240° F. In another embodiment, the filler 255 has a low melt-point or melt-point range, such as a melt-point or melt-point range below about 212° F., such as between about 180° F. and about 90° F., for example, between about 160° F. and about 115° F. In one specific embodiment, the filler 255 is a metal alloy having a melt-point of about 117° F., wherein the filler 255 is in a liquid state at 117° F. or greater and in a solid state at 116° F. or less. In another embodiment, the filler 255 is a metal alloy having a melt-point of about 136° F., wherein the filler 255 is in a liquid state at 136° F. or greater and in a solid state at 135° F. or less. In another embodiment, the filler 255 includes a melt-point or melt-point range between about 110° F. and about 160° F.
In one embodiment, the joint housing 240 and the connecting member 125 are typically made of a material that is significantly more heat-tolerant than the filler 255, wherein the material comprising the joint housing 240 and/or connecting member 125 may withstand temperatures between about 100° F. to about 500° F. higher than the melt-point or melt-point range of the filler 255 without affecting the integrity of the joint housing 240 and/or the connecting member 125. In some embodiments, the material comprising the joint housing 240 and/or connecting member 125 may withstand temperatures significantly greater than the melt-point or melt-point range of the filler 255 without affecting the integrity of the joint housing 240 and/or the connecting member 125.
The filler 255 may be chosen, in part, based on mechanical properties of the filler as well as mechanical and physical properties of the components adjacent to, or in thermal communication with, the filler 255 and/or the joint housing 240. For example, components, structures, devices, and the like, that are adjacent to, or in thermal communication with, the joint housing 240, may absorb thermal energy during the heating process and/or after the filler 255 is heated. The absorption of, or exposure to, heat may pose a safety hazard if the heat needed to cause the phase change of the filler exceeds a certain acceptable limit or range. Further, the absorption or exposure of heat may cause thermal expansion of parts or components near, or in thermal communication with, the joint housing 240. Therefore, the choice of filler 255 may depend on the amount of thermal energy required to cause the phase change due to the factors above. The thermal energy or heat may be provided by heating members as described below, but the heat may also be provided by a heated fluid flowed on or near the adjustable joint 250, a portable heating element, a flame, radiation, light, or any other form of energy.
The adjustable joint 250 may also include one or more static members 310 coupled to the joint housing 340. The static members 310 may be included to provide additional shear strength to the connecting member 125, and may additionally function as a guide or limit for the connecting member 125, thus at least partially limiting movement of the connecting member 125 relative to the joint housing 340. Each of the static members 310 may be a rod or shaft substantially statically coupled to the joint housing 340, a fastener, such as a bolt, a screw, or combinations thereof.
As described in
The retention members 415, 418 are configured to act as a fluid seal for the filler 255 as well as minimizing splashing of the filler 255, and may be made of a flexible or compliant material resistant to temperatures encountered by the joint housing 440 used to liquefy the filler 255. Suitable materials include polymers, a silicon material, rubber, a Teflon® material, among others. The retention member 415 may be applied as needed when the joint housing 440 and/or the filler 255 is heated, and removed after adjustment of the connecting member 125 and solidification of the filler 255. Alternatively, the retention member 415 may be a permanent element of the adjustable joint 250. The retention member 418 may include an elastic neck 428 and a flexible junction 430 joined with a compliant skirt 426. The elastic junction 430 may include an inwardly extending lip 432 adapted to seat in a groove 434 formed in the joint housing 440, which may enhance sealing and coupling between the joint housing 440 and the retention member 418.
In operation, the filler 255 is heated by a heat source, such as by the heating members 330, 345 (
Once the filler 255 is heated to at or near the melt-point or melt-point range of the filler, power to the heating members 330, 345 may be maintained, lowered, or turned off, depending on the heat initially provided and/or the adjustment time. As the filler 255 is in this non-solid phase, the transfer means 105 may be positioned and aligned as needed with or without the continued energy from the heating members 330, 345. Once the adjustment and/or alignment is made, any power supplied by the heating members 330, 345 is halted, and the holding means 500 is used to restrict movement during cooling and solidification of the filler 255, which requires the filler 255 temperature to be below the melt-point or melt-point range. This cooling period may be a relatively short or long period depending on the temperature of the filler 255, the mass of the filler 255, and/or the mass or construction of the joint housing 240, but the period may be shortened by cooling the filler with a fluid or other cooling means. Once the filler 255 is solidified, the holding means 500 may be removed and the transfer mechanism 200 may be put into service.
In the exemplary embodiments depicted and described herein, the adjustable joint 250 may comprise a process kit or replacement part that may replace the existing joints or interfaces between two or more structures, devices, or mechanisms. For example, an existing joint, such as the joint 150 of
Embodiments of an adjustable joint 250 as described herein meets or exceeds some of the challenges faced when adjusting or aligning one element relative to another element on a piece of equipment. For example, the adjustable joint 250 includes no screws to tighten or adjust, which may significantly reduce downtime if access to the joint is restricted. The filler 255 allows six degrees of freedom when in a viscid, semi-viscid, or liquefied state and once the filler 255 has solidified, there is no tendency for one adjustment to affect another adjustment as described in reference to the adjustment members 135 of
While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.