The present invention relates generally to pallets for assembly plants, and more specifically to a reconfigurable pallet.
During assembly of vehicles in an assembly plant individual components must be supported prior to installation in the vehicle. In the case of heavy or bulky components it may be necessary or desirable to support these components in a specific configuration which facilitates installation of the component into the vehicle. For example, it may be desirable to support the component in an orientation which corresponds to its in-vehicle orientation and in a manner which enables access to locations, such as boltholes, used to attach the component to the vehicle.
An example of this is a vehicle engine or powertrain (i.e. engine plus transmission), where engine and/or powertrain specific support structures are used for the purpose of presenting the engine or powertrain to the vehicle body in a manner which facilitates attachment of the engine or powertrain to the vehicle body.
Commonly, customers may be offered various hardware options, such as engines or powertrains, with a specific vehicle body. Hence, to meet the need described above, multiple support structures must be employed each of which will be specific to a single hardware option or component version and which will be incapable of being used for other options. Frequently, for convenience and to ensure their strength and rigidity, these support structures are mounted on a platform. Together the support structure and the platform to which is attached constitute a pallet. As a result, a unique pallet is required for each version of the component associated with the assembly line.
A pallet that can be reconfigured to support multiple versions of a component associated with an assembly line is desired.
A pallet of the present invention includes a platform and a plurality of support assemblies located at multiple positions on the platform. One support assembly is associated with each support location of the component. The support assemblies each include a support element and a plurality of bases, one base for each version of the component to be supported.
The support element is positioned on the desired base. An interface on the base for receiving a footing of the support element places the support element in the desired location. The support element includes a locator. Once positioned on the base, the locator corresponds to a predetermined location on the component which has a mount for alignment. The height of the interface places the locator at the appropriate height for the mount of that version of the component.
The support element may be constrained by a linkage assembly. The linkage assembly has a foundation secured to the platform. A first arm is rotatably connected to the foundation with a first joint and a second arm is rotatably connected to the first arm with a second joint. An aperture for receiving the support element is defined by the second arm.
An alignment mechanism is associated with each base. An extension protruding upwards from the base is received within a recess defined by the support element. The support element is positioned such that the recess is located above the extension. The support element is then rotated until an elongated portion is aligned with a planar wall on the base. Once aligned the support element can be moved vertically to seat the footing on the base. To configure the support assembly for another version of the component the footing is moved from the interface of the current base to the interface of another. The support element is rotated until the elongated portion and the planar wall of that base are in alignment.
An error proofing mechanism is provided for each support element and includes a relay mechanism associated with each base. Once in the support element is in the proper alignment and fully seated on the desired base the elongated portion of the footing contacts a contact surface on the relay mechanism. A signal is sent from the relay mechanism to a control unit which confirms the support element is mounted on the correct base and provides an indicator showing confirmation.
The support assemblies allow the pallet to quickly and easily be reconfigured by a single operator. Associating an alignment mechanism with each base allows each support element to be rotationally positioned relative to the pallet providing precise mounting locations. Thus, the pallet accommodates relatively minimal lateral differences between desired mounting locations of different versions of the component. Providing a reconfigurable pallet to be used with multiple versions of a component on an assembly line reduces costs.
The invention also includes an improved method for reconfiguring a pallet. The method comprises positioning a support element above one of a plurality of bases via movement of a linkage assembly, rotating the support element until an elongated portion of the support element is aligned with a planar wall of the one of the plurality of bases, and sliding the support element relative to the linkage assembly to mount the support element on the one of the plurality of bases.
The above features and advantages, and other features and advantages of the present invention will be readily apparent from the following detailed description of the preferred embodiments and best modes for carrying out the present invention when taken in connection with the accompanying drawings.
a is a schematic view illustrating alignment of multiple bases of the support assembly for the pallet of the present invention;
b is a schematic view illustrating alignment of one base and the support element with another base of the support assembly for the pallet of the present invention; and
c is a schematic view illustrating alignment of one base with another base and the support element of the support assembly for the pallet of the present invention.
a is an enlarged perspective view another illustrating alignment of the error proofing mechanism of the present invention;
b is an enlarged perspective view illustrating alignment of the error proofing mechanism just prior to contact of the support element and the base;
Referring to the Figures, wherein like reference numbers refer to the same or similar components throughout the several views,
The pallet 10 includes a platform 12 and a plurality of support assemblies 14 located at multiple positions on the platform 12. As shown, four support assemblies 14a-d are located one at each corner 16 of the platform 12. One support assembly 14 is associated with each support location for the component. The number and location of the support assemblies 14 is determined by the design and type of the component to be supported. An x, y and z direction are defined by the pallet 10. Each support assembly 14a-d is located at a specific x-y-z coordinate as described below.
Referring to
The support element 18 is positioned on the desired base 20, in this instance base 20c. The support element 18 has a footing 26. The footing 26 couples with the desired base 20c. In the embodiment shown, the multiple bases 20a-c each have an interface 28 for mating with the footing 26. The interface 28 places the support element 18 in the desired x-y coordinate location. The interface height HI of the desired base 20c places the locator 22 at the appropriate component height HC for that version of the component. Therefore, each base 20a-c is associated with a specific x-y-z coordinate appropriate to the version of the component being supported on the pallet 10 by the base 20a-c.
The interface 28 includes an alignment mechanism 46. The alignment mechanism 46 places the support element 18 in the desired rotational alignment for that corresponding base 20, here base 20c. The locator 22 may be placed in an eccentric location relative to axis 50 of the support element 18. By providing rotational alignment of the support element 18 the locator 22 may be placed in multiple x-y coordinate positions that are relatively close to one another, as explained with respect to
Each support element 18 is constrained by a linkage assembly 30. The linkage assemblies 30 guide and support the support element 18 and ensure that there are no loose parts associated with the pallet 10 to prevent dropping parts during pallet reconfiguration. However, the support element 18 could be detached from the linkage assembly 30 if so desired. Each linkage assembly 30 has a foundation 32 secured to the platform 12. A first arm 34 is rotatably connected to the foundation 32 with a first joint 36. A second arm 38 is rotatably connected to the first arm 34 with a second joint 40. An aperture 42 for receiving the support element 18 is defined by the second arm 38 and is positioned remotely from the second joint 40. The support element 18 can freely rotate and slide in the z direction when located within the aperture 42.
The first joint 36 rotatably connects the first arm 34 to the foundation 32. The first arm 34 rotates about a first axis 44 that is oriented in the z direction. The second joint 40 rotatably connects the second arm 38 with the first arm 34. The second arm 38 rotates about a second axis 48 that is also oriented in the z direction, and is parallel to the first axis 44. The x-y coordinate location of the second axis 48 may be changed by rotating the first arm 34 about the first axis 44. Once the support element is mounted on the interface 28 rotation of the first arm 34 about the first axis 44 and the second arm 38 about the second axis 48 is prevented. This prevents movement of the first arm 34 and the second arm 38 relative to the foundation 32 and thus, to the platform 12.
The support element 18 rotates within the aperture 42 about a third axis 50 that is oriented in the z-direction and parallel to the first and second axes 44 and 48. The x-y coordinate location of the third axis 50 may be changed by rotating the second arm 38 about the second axis 48 when the support element 18 is not received within the interface 28. Once the footing 26 is received by the interface 28, the x-y coordinate location of the third axis 50 is fixed. Gravity and weight of the component restrict the support element 18 from moving along the third axis 50 during pallet 10 usage.
To configure the support assembly 14c for another version of the component the footing 26 is moved from the interface 28 of base 20c to the interface 28 of base 20a or 20b, as desired, and the support element 18 is moved within aperture 42 for vertical adjustment.
To reconfigure the entire pallet 10 this is repeated for each of the support assemblies 14a-d located on the pallet 10. To ensure proper positioning of the support element 18 for each of the support assemblies 14a-d the bases 20 may be colored or numbered alike for each version of the component. That is, base 20a of support assembly 14c has a matching color to a similar base 20a of each of the support assemblies 14a, b and d on the pallet 10. Base 20b of support assembly 14c would have another color matching each similar base 20b of each of the support assemblies 14a,b and d and base 20c of support assembly 14c would have a third color matching each similar base 20c of each of the support assemblies 14a, b and d. Positioning the footings 26 for each support assembly 14a-d with similarly colored bases 20 to one another would ensure that the locators 22 are in the proper location for each version of the component. For example, the component is an engine and each version of the engine would have a color associated therewith. All of the bases 20 utilized to support that engine version would be the associated color.
In addition to coloring the bases 20 to ensure proper positioning of the support element 18, an error proofing system 70 may be associated with each support assembly 14a-d. The error proofing system 70 provides an indication showing when the support element 18 is in the proper base 20a-c and may also provide an indication of the appropriate remedial action to be taken if the support element is in an improper base 20a-c. The error proofing mechanism includes a power source, sensors, a communication device and, optionally, a controller associated with each platform 12. More specifically, each base 20 and support element 18 will incorporate at least one sensor. The power source, not shown on the figures for clarity, may be mounted directly on platform 12 as for example a battery, or may be remotely located and the power transmitted to platform 12 and the error-proofing system 70 specifically by either contact, for example mating complementary male-female connectors, or non-contact means, for example inductive coupling. A wide range of sensors may be used provided they are capable of determining whether or not a specific support element 18 is mounted on its appropriate base 20a-c. Examples, without limitation, include a mechanically-activated switch; magnetic sensors such as Hall effect sensors, or proximity sensors; and optical sensors, either transmissive or reflective. Depending on the choice of sensor and the nature of the output from that sensor, a controller may be required to interface with a communication device capable of providing an operator with information regarding the state of the platform 12 and, more specifically whether the support element 18 and the base 20a-c combinations created on the platform constitute a self-consistent set. In other words are the bases 20a-c all part of the same subset so that all support elements 18 on the platform are attached to their respective base 20a or to their respective base 20b or to their respective base 20c or is one support attached to a different base 20a-c. If required, the role of the controller will be to transform the sensor signal into a signal compatible with the requirements of the communication device. The communication device may provide: a visual indication, for example a light emitting diode or a plurality of light emitting diodes; an aural indication, for example a buzzer or loudspeaker; a tactile indication, for example a vibratory stimulus; or any combination of these. Similarly, the communication device may indicate the current status of the platform 12 or, if the platform 12 is inappropriately configured, it may also suggest corrective action. In the specific embodiment illustrated in
The bases 20a-c for each support assembly 14a-d may have different interface heights HI than one another. That is, the interface height HI for the base 20a of the support assembly 14a may differ from the interface height of the base 20a of the support assembly 14b which differs from the interface height of the base 20a of the support assemblies 14c and 14d. Alternatively, all the bases 20a-c may be the same height and shims located between the base 20a-c and the platform 12 can be used to adjust the interface height HI for each base 20a-c. The interface height HI for the bases 20a-c is determined by the component mount requirement at each support assembly 14a-d location for that version of the component.
The alignment mechanism 46 defines an extension 54 located on the base 20 and a recess 62 defined by the footing 26 of the support element 18. Alternatively, the support element 18 could define an extension including a planar wall and the base 20 could define a recess having a flat interior surface to align with the planar wall of the support element 18.
a-6c illustrate the alignment of the footing 26 and the interface 28 to position the locator 22.
b is a top view of the base 20b and the support element 18 positioned on base 20a. The locator 22 has an off-center location with respect to the support element 18. That is, the locator 22 is eccentrically located from the third axis 50 about which the support element 18 rotates. By aligning the elongated portion 64 with wall 56 the locator is rotated to the same position as the desired mounting position 68a (shown in
A series of display indicators 82a, b, c is provided wherein the letter indices (a, b or c) for the display lights correspond to the similarly indexed base 20a-c. For example illumination of display indicator 82a would correspond to closure of contact mechanism 72 on base 20a. The display indicators 82a-c may be mounted individually on either the respective switch 76 or base 20a or indicators from all bases 20a-c may be displayed in a common location, display unit 80.
Once the support element 18 is mounted on the base 20 one of the display indicators 82 is activated. The display indicators 82a, b, c are preferably light emitting diodes (LEDs) but any active display including incandescent lights, liquid crystal displays (LCDs) and electro-luminescent displays may be used without restriction. The LEDs are preferably multi-colored, each color being associated with one base 20a, b or c and thereby to one version of a component to be supported by the pallet 10. In this embodiment when one of the support elements 18 is mounted to an incorrect base 20 a display indicator 82a-c of different color than the other bases 20a-c would be illuminated. This mismatch between the color of the display indicators 82a-c would indicate to an operator that an at least one of the support elements 18 had been placed on an incorrect base 20a-c and the one to one correspondence of a particular display indicator 82a-c with a particular support assembly 14 would easily enable the operator to identify the incorrect support assembly 14 and take remedial action. Providing an indication of the correct base 20 would save the operator time from having to determine which base 20a-c is proper, or where the error is occurring.
An electrical circuit 90 to enable this embodiment is shown in
Note that the embodiment of
a and
In the above embodiments an example of the component to be supported is an engine. This is in no way meant to be restrictive and other components may be utilized with the reconfigurable pallet of the present invention.
While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims.