Accumulation pallet conveyor, for recirculating a plurality of pallets in an endless horizontal carousel, and method for controlling this conveyor

Patent metadata

Field	Value
Publication number	US-9376258-B2
Application number	US-201314075596-A
Country	US
Kind code	B2
Filing date	Nov 8, 2013
Priority date	Nov 20, 2012
Publication date	Jun 28, 2016
Grant date	Jun 28, 2016

Abstract

A plurality of different types of components is fed to a production line or cell by means of a conveyor for recirculating a plurality of pallets on which said components are carried. The conveyor comprises a horizontal carousel for recirculating the pallets along an endless path. The conveyor is able to cause the pallets to circulate in any of the two circulation directions, and the direction of circulation of the pallets is changed according to the type of component required by the production line or cell in each step of operation, in such a way as to carry a component of the type required to the production line or cell in the shortest possible time. The conveyor comprises a single chain-tensioning device designed to tension the chain properly whenever the direction of movement of the chain is reversed.

First claim

What is claimed is:

1. A production system including a production line or cell and an accumulation conveyor for feeding a plurality of different types of components to said production line or cell, said accumulation conveyor being designed to recirculate a plurality of pallets along an endless horizontal path, said system comprising:
an accumulation conveyor having a supporting structure;
an endless chain engaged on sprocket wheels rotatably mounted about vertical axes on said supporting structure;
a motor controlling movement of said endless chain;
a loading area adjacent to said accumulation conveyor for loading of said components on the accumulation conveyor;
an unloading area where said components are unloaded from said accumulation conveyor to be transferred to said production line or cell, said unloading area being adjacent to said accumulation conveyor and being located at a position spaced apart from said loading area along said endless horizontal path;
a plurality of pallet-carrying members drawn by said chain along said endless horizontal path, each pallet-carrying member being provided with means for engaging the chain that enable said chain to move freely with respect to a pallet-carrying member such as where the latter is stopped in a given position along the accumulation conveyor;
a plurality of independent pallets, each carried by a respective pallet-carrying member and prearranged for conveying one or more of said components of different types from said loading area for receiving said components on the accumulation conveyor to said unloading area where said components are unloaded from the accumulation conveyor;
an electronic control station having one of a predetermined component sequence or a detector adapted to detect a component sequence of said components to be supplied to said production line, the electronic control station adapted to output a component sequence signal; and
an electronic control unit in signal communication with said electronic control station and said motor, said electronic control unit adapted to receive said electronic control station output signal and control said motor to selectively drive said pallets in a selected one direction of circulation or in the other direction in response to the electronic control station component sequence signal to supply the required component to the production line.

2. The system according to claim 1 , wherein said pallets further comprise a plurality of supports adapted to contact at least one of components of different models of motor vehicle and different components for each model of motor vehicle to enable rapid variation of the type and quantities of the vehicle models produced and achieve corresponding vehicle production percentages.

3. The accumulation conveyor according to claim 1 , wherein the pallets are coupled to respective pallet-carrying members prearranged along the accumulation conveyor so that it is possible to replace any number of pallets prearranged on the accumulation conveyor in order to have pallets adapted to any specific desired type of component and to any specific desired mix of components.

4. The accumulation conveyor according to claim 1 , wherein the accumulation conveyor comprises a single chain-tensioning device for tensioning the chain in the two opposite directions so as to guarantee proper tensioning of the chain whatever the direction of movement of the chain.

5. An accumulation pallet conveyor for feeding a plurality of different types of components to a production line or cell, designed to recirculate a plurality of pallets in an endless horizontal carousel, said conveyor comprising:
a supporting structure;
an endless chain engaged on sprocket wheels rotatably mounted about vertical axes on said supporting structure;
a motor connected to said endless chain for selectively driving said endless chain;
a plurality of pallet-carrying members drawn by said chain along said endless horizontal carousel, each pallet-carrying member being provided with means for engaging the chain that enable said chain to move freely with respect to a pallet-carrying member in the case where the latter is stopped in a given position along the conveyor;
a plurality of pallets, each carried by a respective pallet-carrying member and prearranged for conveying one or more components of different types from an area for receiving said components on the conveyor to an unloading area where said components are unloaded from the conveyor;
a plurality of pallets, each carried by a respective pallet-carrying member and prearranged for conveying one or more components of different types from an area for receiving said components on the conveyor to an unloading area where said component are unloaded from the conveyor;
an electronic control station having one of a predetermined component sequence or a detector adapted to detect a component sequence of said components to be supplied to said production line, the electronic control station adapted to output a component sequence signal; and
an electronic control unit in a signal communication with said electronic control station and said motor, said electronic control unit adapted to receive said electronic control station output signal and control said motor to selectively drive said pallets in a selected on direction of circulation or in the other direction in response to the electronic control station component sequence signal to selectively provide said respective components to the production line;
a single chain-tensioning device for tensioning the chain in the two opposite directions so as to guarantee proper tensioning of the chain whatever the direction of movement of the chain, the chain tensioning device further comprising:
two main chain-tensioning sprocket wheels on which the chain engages in succession;
two main springs that recall the shafts of said main chain-tensioning sprocket wheels in two mutually opposite directions; and
two cam surfaces formed on two auxiliary cam elements or on a single auxiliary element, which engage cam-follower elements operatively connected to the shafts of said main chain-tensioning sprocket wheels so as to tend to push said shafts in said mutually opposite directions under the action of auxiliary elastic means, in such a way that, for each direction of movement of the chain, one of said main chain-tensioning sprocket wheels tensions the chain as a result of its displacement in a first direction caused by the main spring and by the cam surface associated thereto, whilst the other chain-tensioning sprocket wheel is hindered by the cam surface associated thereto from moving in said first direction, the aforesaid functions of the two main chain-tensioning sprocket wheels and the functions of the two cam surfaces being reversed with each other when the direction of movement of the chain is reversed.

6. The conveyor according to claim 5 , wherein the cam surfaces are formed on two levers pivotally mounted on the supporting structure of the chain-tensioning device about two axes set at a distance from one another and each having a cam surface in contact with a cam-follower element operatively connected to the shaft of a respective chain-tensioning sprocket wheel.

7. The conveyor according to claim 6 , wherein the cam surface is shaped in such a way as to maintain substantially constant the overall force due to the main spring and to the auxiliary cam element, applied to the respective main chain-tensioning sprocket wheel, as the deformation of the main spring varies.

8. The conveyor according to claim 5 , wherein the cam surfaces are formed on two opposite end portions of a single lever articulated centrally to the supporting structure of the chain-tensioning device, each end portion having a

Assignees

• Comau Spa

Inventors

• Magni Gianni
• Gromme Gianpiero

Classifications

• B65G17/12 Primary

  comprising a series of individual load-carriers fixed, or normally fixed, relative to traction element · CPC title

• B65G19/02 Primary

  for articles, e.g. for containers · CPC title

• B65G1/133 Primary

  the circuit being confined in a horizontal plane · CPC title