Conveyor trolley system

A trolley unit for a conveyor system comprises first and second releasably engageable trolley half sections. First and second shafts extend from one of said trolley sections and through the other trolley section to provide a pivot axis for an end of upstream and downstream trolley connecting cables. A third shaft provides a support bar for a load attachment hanger. Upon releasable attachment of the trolley halves an integral trolley unit with central housing houses the pivot shafts with the cables extending therefrom. The integral trolley unit is easily dismantled allowing for easy maintenance. A turn sheave includes a cable seat and plurality of trolley seats which inhibit inward deflection of the seated cables and trolleys when the trolleys are moving about a corner of the conveyor system as defined by a change in a horizontal direction of the support rail.

BACKGROUND OF THE INVENTION
 This invention relates to the conveying of products via an overhead trolley
 type conveyor in a meat/food processing facility.
 In a meat/food processing facility it is desirable to control the hygiene
 of the processing environment so as to preclude the introduction of
 contaminates in the product. Various government regulations address
 contaminates and sanitation in meat/food processing facilities. It is also
 desirable to maintain and/or modify conveyor systems with a minimum of
 effort to reduce labor and costs. Furthermore it is desirable to maintain
 safe conveyor systems to avoid injury to personnel and equipment.
 Several problems exist that hinder the meat/food processing facility in
 meeting the government regulations concerning hygiene, maintenance and the
 safety of this equipment.
 One problem is the result of sanitation techniques used on the conveyor
 systems. These systems are sprayed or dipped in a sanitation solution that
 may become trapped in recesses or between components. Current conveyor
 systems, by design, have a significant number of areas to trap
 contaminates. This results in possible contamination due to dripping of
 solution onto product throughout the facility. If product is contaminated
 it must be removed from the production stream and destroyed or utilized as
 rendering at a greatly reduced value.
 A second source of contamination is the direct result of normal wear in
 current metallic based trolley systems. Metal flakes, corrosion,
 lubricants, and broken cable strands can find their way into the meat/food
 products during the normal operation of these systems as they pass over
 areas containing product.
 Current systems are plagued with endless cycles of sanitation. Corrosion is
 accelerated by the use of strong caustic sanitation solutions. Corroded
 parts making contact with other metal parts tend to wear faster than
 normal.
 Failure of an overhead trolley conveyor system is potentially dangerous due
 to unexpected rapid and uncontrolled movement of product on the conveyor
 system. Many components of current systems utilize plated mild steel,
 which corrodes rapidly when exposed to caustic sanitation solutions. Those
 systems utilizing corrosive resistant cable do not address the problem of
 stress on the cable mounting points resulting in premature fracturing of
 the cable strands. These systems are hard to inspect resulting in
 overlooked damage and unrecognized danger. Because these systems utilize
 metal to metal engagement of components they must also use lubricants. The
 lubricants are constantly depleted during the sanitation process and pose
 a contamination threat themselves.
 Maintenance costs of current conveyor systems are significant due to the
 need for constant lubrication, replacement of parts that show excessive
 wear, corrosion, and fracturing. Modification and repair of current
 systems must be performed at designated areas away from meat/food
 products. Current systems utilized complex trolleys with multiple
 components fastened together. Replacing trolley components can require
 more multiple maintenance personnel to perform the repair. Current Systems
 typically use continuous lengths of cable or chain for an entire system.
 Often, cutting equipment and special power tools are required to repair or
 modify the conveyors. This results in additional loss of use and increased
 costs. If a current conveyer system should fail, the system must be
 advanced to a safe area for repair. If this is not possible then product
 must be removed from the work area to avoid contamination. This procedure
 and subsequent cleanup of the work area increases costs substantially.
 Finally, current systems create noise due to metal to metal contact. This
 adds to the overall ambient noise level that could be detrimental to the
 work force.
 SUMMARY OF THE INVENTION
 In response thereto we have invented an improved conveyor trolley system
 which eliminates or reduces the potential of product contamination in a
 meat/food processing facility while minimizing maintenance, modification
 costs, and noise. Our system utilizes a combination of polymer-based
 materials and corrosive resistant steel formed into a series of trolleys
 connected by individual cable sections. These components are supported
 vertically by commercially available wheels rolling along a system of
 commercial tee rails. The conveyor is able to transport products to any
 point within the facility along the conveyor path utilizing trolley hanger
 attachments as designated by the user. Our system utilizes specially
 designed turn sheave assemblies to drive the system along the tee rails
 and support the trolley hanger components as they change horizontal
 directions during normal travel along the conveyor path. The precision
 design of the trolley hangers and turn sheave assemblies allows them to
 work together and minimize all stress and wear associated with changing
 directions. The combination of the design and the materials used to make
 the trolley hangers and turn sheaves make them very quiet. The specially
 designed cable end fitting working in conjunction with the trolley hanger
 attachment point will allow an extreme angle of deflection with no
 detrimental stress placed on the cable or cable end fitting. This results
 in an extremely flexible and long lasting system. Lubrication is
 eliminated with the use of polymer-based materials and the design of the
 cable end fitting and the trolley hanger attachment points. Our system may
 be repaired or modified at almost any point in the system using only
 common hand tools.
 It is therefore the objective of this invention to present an improved
 trolley conveyer system to minimize the contamination of meat/food
 products in a processing facility, reduce the overall cost of maintenance,
 and improve safety.
 The object of the polymer-base trolley hangers is to eliminate harmful
 corrosion.
 Another object is to eliminate areas capable of trapping contaminating
 fluids.
 Further object of the polymer-based trolley hangers is to minimize noise.
 Further object of the polymer-based trolley hangers is to reduce wear.
 The object of the polymer-based turn sheaves is to form sheave turn
 assemblies and work in conjunction with the polymer-based trolley hangers
 to provide smooth propulsion and horizontal transition for the conveyor
 system through the turns.
 Another object of the polymer-based turn sheaves is to support the trolley
 hangers and remove detrimental stress from the cable and cable end
 fittings.
 Further object of the polymer-based turn sheaves is to eliminate corrosion.
 Further object of the polymer-based turn sheaves is to eliminate areas
 capable of trapping contaminating fluids.
 Further object of the polymer-based turn sheaves is to minimize noise.
 Further object of the polymer-based turn sheaves is to minimize wear
 between the trolley hangers and the turn sheaves.
 Another object of this invention is to eliminate the need for lubrication
 of the conveyer system.
 Another object of this invention is to reduce the maintenance costs of the
 conveyor system.
 Another object of this invention is to improve the ability to modify the
 conveyor system.
 Another object of this invention is to improve inspection capabilities and
 avoid dangerous failures.
 Another object of this invention is to eliminate stresses that tend to
 fracture the cables in the system.
 Another object of this invention is to provide the capability of rapid
 replacement of worn or damaged parts at convenient locations.
 Other advantages of this invention will become apparent from the following
 description taken in connection with the accompanying drawings, wherein is
 set forth by way of illustration and example, an embodiment of this
 invention.

DESCRIPTION OF PREFERRED EMBODIMENT
 Referring to the drawings, FIGS. 1-8 show an improved trolley conveyor
 system comprised of components designed to work in conjunction with each
 other and address specific problems in the meat/food processing industry.
 This system represents an easily installed, low maintenance trolley
 conveyor with exceptional sanitation properties. This improved conveyor
 system utilizes trolley hangers 100 (FIGS. 1,2) designed to eliminate
 contamination of meat/food products through the use of selected materials
 and geometrical shapes. Trolley hangar halves are bolted together to form
 trolley hangers 100 which are coupled to commercial tee rails 300 though
 the use of commercial rollers 600. The trolley hangers 100 form the
 portion of the conveyor that supports the weight of the product during
 travel. User specific attachments can be mounted on the trolley hangers
 utilizing the bottom bolt FIGS. 2 & 3). Cable assemblies 500 (FIG. 7)
 connect multiple trolley hangers 100 to achieve the desired length for the
 cable system. Cable assemblies 500 are composed of a length of cable with
 a cable end fitting 400 (FIG. 8) attached to each end. The cable end
 fittings 400 attach to pivot points on trolley hangers 100 (FIG. 3). This
 design will allow the cable assemblies 500 to pivot, as necessary, between
 trolley hangers 100 as they travel along the supporting tee rail 300.
 Allowing the cable assemblies to pivot as illustrated in FIG. 3 eliminates
 virtually all side stress on the cable assemblies 500. Detrimental stress
 is further reduced by using specially designed turn sheaves 200 bolted to
 a center hub 800 to form a turn sheave assembly which supports the trolley
 hangers 100 and cable assemblies 500 during a horizontal turn. The turn
 sheaves 200 are designed to work in conjunction with the trolley hangers
 100 to restrict the depth of the trolley hanger 100 penetration between
 the sheaves 200 (FIGS. 4 & 6). The turn sheaves 200 are also designed to
 support the cable assembly 500 during a turn without placing force
 directly on the cable end fitting 400 or the pivot point of the trolley
 hanger 100 (FIG. 5). This insures the cable assembly 500 is never forced
 out of the designed pivot range or flexed detrimentally. A turn sheave
 assembly may also assume the function of transmitting drive propulsion to
 the conveyor system. Safety and reliability are improved because the
 trolley hangers 100, turn sheaves 200, and cable assemblies 500 work
 together to reduce deterioration from stress. If repairs become necessary,
 the components may be replaced at almost any location along the conveyor
 system. Each cable assembly 500 may be replaced by removing one pivot
 point mounting bolt at each end using common hand wrenches (FIG. 3). This
 technique has an added benefit over current systems by leaving the trolley
 hanger 100 intact on the tee rail 300. Trolley hanger halves may be
 replaced by simply removing four bolts with common hand wrenches. The
 entire conveyor system requires no lubrication due to the use of selected
 materials and design flexibility thus eliminating one final source of
 potential contamination.
 It can be appreciated that this improved trolley conveyor system represents
 significant advantages for the meat/food processing industry. Accordingly,
 the minimization of contamination insures a safer supply of meat/food to
 consumers while improved reliability and safety enhance the environment
 for meat/food processing workers.