Carrier conveyor system |
|||||||
申请号 | US10421354 | 申请日 | 2003-04-23 | 公开(公告)号 | US06997303B2 | 公开(公告)日 | 2006-02-14 |
申请人 | Melvin A. Edwards; Christopher L. Audia; Kelsey R. Schell; David M. Stewart; | 发明人 | Melvin A. Edwards; Christopher L. Audia; Kelsey R. Schell; David M. Stewart; | ||||
摘要 | The present invention is directed to a carrier and conveyor system that permits the carrier to be driven by at least two different types of conveyors or drive assemblies, including a power and free conveyor. The system includes a plurality of carriers, first and second areas, a power and free conveyor assembly, and a friction drive assembly. The power and free conveyor drivably engages the first and second carriers when the carriers are in the first area and is out of driving engagement with the carriers in the second area. The friction drive assembly is engageable with each carrier when the carriers are in the second area and out of driving engagement with each carrier when the carriers are in the first area. | ||||||
权利要求 | What is claimed is: |
||||||
说明书全文 | This application claims the benefit of U.S. Provisional Application No. 60/375,283, filed Apr. 24, 2002, the entire disclosure of the application is considered part of the disclosure of this application and is hereby incorporated by reference. The present invention relates to a conveyor system for transporting carriers through a production facility and, more particularly, to a conveyor system that includes a power and free conveyor to transport the carriers through a first area and a second conveyor assembly to transport the carriers through a second area. Conveyor systems are commonly used in manufacturing environments to transport workpieces. In many of these systems, the workpiece(s) is mounted to a carrier that is then drivably engaged by a conveyor. A number of conveyor and carrier styles are available in the art with a suitable configuration being selected based upon the demands of a particular application. In many complex manufacturing environments it is desirable to capitalize upon the operational benefits of different conveyor systems. In such instances, it is commonly necessary to transfer workpieces to and from carriers that are specifically configured for use with the particular conveyor. Conventional skid conveyors, a combination of a skid and truck with rollers, with a chain on edge as the primary truck drive have been combined with a roller or belt conveyor to drive the truck in areas where accumulation, indexing, and switching of the trucks and workpieces is desired. However, in these systems, the accumulation, indexing, and switching capabilities are limited to areas where the chain drive is disengaged from the trucks. Further, the trucks are provided with additional components, such as rollers, to stabilize the truck when driven by the chain. Power and free conveyors are also commonly used in the art to provide accumulation, indexing, and switching of carriers. However, power and free conveyors generally lack the degree of stability desired for certain assembly operations. Accordingly, the art has failed to develop a conveyor system that provides accumulation, indexing, and switching capabilities outside of assembly areas and adequate stability within the assembly areas. With the above in mind, the present invention is directed to a carrier and conveyor system that permits the carrier to be driven by at least two different types of conveyors or drive assemblies so as to provide a conveyor system having benefits and advantages not previously achieved in the art. More particularly, the invention is directed to a carrier (such as a skid) and a conveyor system that includes a power and free conveyor for moving the carrier through a first area and a friction drive assembly (such as a roller conveyor, belt conveyor, or other friction drive) that moves the carriers through a second area. Further scope of applicability of the present invention will become apparent from the following detailed description, claims, and drawings. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art. The present invention will become more fully understood from the detailed description given here below, the appended claims, and the accompanying drawings in which: As is shown in the attached drawings, the present invention is generally directed to a production operation 10 wherein workpieces 12 (such as the illustrated automobile bodies) are mounted to carriers 14, such as the illustrated skids, and transported by a conveyor system that includes a power and free conveyor 16 for driving the carriers in a first area 18 and a second drive assembly 20, such as the illustrated roller tables, for driving the carriers in a second area 22. In the illustrated embodiment, the skid carrier 14 has laterally spaced rails 30 ( As is shown in While power and free conveyors efficiently transport articles through a variety of manufacturing environments, there are instances where other conveyor or drive mechanisms may be uniquely suited for a particular application. For example, skids are commonly transported along conveyor tables that permit the indexing of carriers for downstream processing. Such skid conveyor tables may include alternative drive components such as rollers, belts, and/or friction drives that engage the spaced skid rails to support and transport the skids. A representative roller table 56 is shown in The transfer of the carriers between the power and free conveyor and the roller conveyor illustrated in Similarly, when a carrier, e.g., 14b, enters a second transfer zone 68 at the downstream end 70 of the second area 22, a power chain 72 engages the drive trolley 42 at a wipe-on point 74. While two separate power chains 66 and 72 are illustrated in As noted above, the drive and free trolleys 42 and 40 coupled to each carrier 14 ride in the free track 48 as the carrier 14 is driven by the second drive assembly, e.g., roller table 56. In order to ensure that the free trolleys do not impact the engagement between the driven rollers 58 and the skid rails 30, the vertical spacing 80 ( To facilitate the movement of the skid rails onto the roller table 56 in the entrance transfer zones, each skid rail preferably includes a beveled front section 82 ( Based on this description and the appended drawings, it should be apparent that by fixing the trolleys to the carriers and modifying the configuration of the roller table to include a free track that accommodates the trolleys when the carrier is being transported by the roller table, the present invention permits the use of a power and free conveyor in a first area and a second drive assembly in a second area without requiring the transfer of the workpiece or article to a different carrier. The invention has been described with reference to the transportation of a skid through a production facility. However, those skilled in the art will appreciate that a variety of carrier configurations may be used without departing from the scope of the invention. Other exemplary carrier configurations include a skillet or pallet as described in Applicant's U.S. Pat. No. 6,494,304 issued Dec. 17, 2002 and entitled “Production Operation With Power And Free Pallet Conveyor,” which is hereby incorporated by reference in its entirety. Further, while the second conveyor assembly is illustrated and described herein as a skid table, using either rollers or belts to engage and transport the skid, it should be appreciated that other conveyor assemblies may be used. For example, the system described in U.S. Pat. No. 6,494,304 describes a friction drive assembly that engages the sides of the pallet or skillet to move the carrier through a production area. The foregoing discussion discloses and describes an exemplary embodiment of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims. |