GB2197633A

GB2197633A - Apparatus for sorting items

Info

Publication number: GB2197633A
Application number: GB08726185A
Authority: GB
Inventors: Francesco Canziani
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-11-10
Filing date: 1987-11-09
Publication date: 1988-05-25
Anticipated expiration: 2007-11-09
Also published as: FR2606301B3; IT8622264A0; DE8714976U1; ES1005977Y; IT8622264A1; JP2529687Y2; FR2606301A1; JPS6396027U; GB2197633B; GB8726185D0; IT1198074B; ES1005977U

Abstract

Apparatus for sorting items such as letters or packages consists of a plurality of carriages driven along a fixed path, and provided each with a conveyor surface (6, 12) on which the item to be sorted is placed. Along the path are located unloading stations, at least some of which comprise a number of discharge levels or mouths, located one above another, through which mouths the unloaded item is sent to different final destinations. Each carriage has means (8, 15) for positioning the conveyor surface (6, 12) at the height of a desired mouth so as to unload the item to the pre-determined mouth. This enables the overall length of the whole apparatus to be reduced. The carriages may be attached to a vertical belt 17 or may each carry an electric motor energised by means of contacts engaging a bus bar. The carriages are positioned at different heights by means of a lazy-tong arrangement, or telescopic means. The conveyor surface (6, 12) may be an endless belt, or a tilting plate. <IMAGE>

Description

APPARATUS FOR SORTING ITEMS This invention relates to apparatus for sorting items such as letters or packages.

Sorting apparatus are known comprising a plurality of carriages driven along a fixed path and provided each with a conveyor surface on which the item to be sorted is laid, which conveyor surface unloads the carried item when the carriage passes before a relevant collecting device or unloading station.

This kind of apparatus is described, for example, in the present Applicants' Italian Patent Applications No.'s. 22482 A/82; 22264 A/84; 23110 A/84; 20779 B/B5; 19280 A/79; 21835 A/82; 20722 B/84; 20636 B/85; and Italian Patents No's 1.076.736 and 1.092.781.

In some of these apparatus the conveyor surfaces are tiltable plates, revolving belts, or just conveyor surfaces provided with pusher elements, that unload the items as they move along the surface in either direction.

What these apparatus try to achieve is an ever increasing efficiency, to be obtained by increasing both the number of the handled items and that of the final destinations, and by reducing the apparatus size to the maximum possible extent.

Limiting the length of the fixed path answers various needs, namely those of having to locate the apparatus in rooms of often limited size, of substantially cutting the costs and of using the apparatus to its fullest extent. It should be noted, in fact, that each carriage runs empty once it has unloaded a carried item, and that therefore the time taken up to return to the starting point is actually dead time.

A partial solution to this problem is put forward in the present Applicant's Italian Patent Application No. 25367 A/79 which describes a sorting apparatus wherein the unloading stations are hoppers having several inner pathways and movable walls, actuated by pneumatic means, which, according to their position, drive the unloaded items towards one such pathway or the other. In this way it is possible, while keeping the number of final destinations unchanged, to reduce the apparatus size, the number of carriages, and the installation and maintenance costs as well as the dead time.

This is not applicable, however, to apparatus of more recent construction where it is possible considerably to increase the forward speed of the carriages thanks to the adoption of special motors that control the actuation of the unloading means, and the use of computerized systems to control the whole apparatus.

It may happen that the items laid on two adjacent carriages must be unloaded into the same hopper but towards different final destinations. In this case the time necessary to move by pneumatic means the movable walls that are inside the hopper is greater than the time interval between two successive unloading operations, so that the second unloaded item could be driven to a wrong collecting device.

There is thus a need for a generally improved sorting apparatus which minimises the above disadvantages.

According to the present invention there is provided an apparatus for sorting items, including a plurality of conveyor surfaces for carrying items to be sorted, which conveyor surfaces are movable along a fixed path past a series of unloading stations, with at least some of the unloading stations being in the form of a number of discharge levels or months located one above another and leading to separate storage containers or collectors and including means operative adjustably to position the conveyor surfaces selectively at the height of a desired discharge level or mouth, for discharge of a carried item at that level, during movement of the conveyor surfaces along the fixed path.

The location of a conveyor surface at the height of a desired discharge level or mouth may be effected as the carriage approaches the unloading station, which reduces the time necessary, while the unloading stations, which do not have movable walls and the relevant control devices, are always ready to receive at any time items being unloaded.

For a better understanding of the present invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figures 1 and 2 are perspective views of a carriage of an apparatus according to the invention, with a conveyor surface in two different positions; Figures 3,4 and 5 are perspective and sectional views of apparatus according to a further embodiment of the invention, and Figures 6 and 7 are cross-sectional views through another embodiment of apparatus according to the invention.

A carriage 1 (Figures 1 and 2) runs along a fixed path consisting of a monorail 2, driven by a fixed location motor 3 that is fed with electric supply current, by sliding contacts 4, from a series of bus bars 5 set along the fixed path.

On the carriage 1 is mounted a conveyor surface and unloading device consisting essentially of a rotatable belt 6, mounted on rollers and driven by a motor 7 in either direction orthogonally to the direction of movement of the carriage 1.

The belt 6 and the relevant actuation means are mounted on the carriage via a foldable articulated parallelogram or lazy-tongs structure 8 that is opened or closed by rotation of a screw-threaded shaft 9 in mesh with a cursor secured to the structure 8 and rotated by a motor 10, so as to raise the belt 6 to the desired height.

Along the fixed path are located a plurality of unloading stations, at least some of which comprise two or more discharge levels or mouths located one above another and leading to separate storage containers or collectors.

These unloading mouths can simply consist, for instance, of superimposed chutes such as the ones indicated at 11 in Figures 4 and 5.

The operation of the apparatus is as follows: The carriages, whose structure 8 is in the completely folded position as shown in Figure 1, pass before a loading station where an operator can place on each belt 6 an item to be sorted and at the same time input in known manner a coding corresponding to the desired ultimate destination.

The whole apparatus is controlled by a central computer that stores the data input at the moment of loading, and operates accordingly all the apparatus functions.

The carriages move forward along the monorail 2. When each carriage approaches the desired unloading station, the computer by means of the bus bars 5, actuates the motor 10 so as to lift the belt 6 and to bring it to the level of the unloading mouth corresponding to the final destination of the item. This operation is performed as the carriages move towards their respective unloading stations.

When the carriage passes past the pre-selected unloading station, the computer drives motor 7 to rotate the belt 6, thus unloading the item into the adjacent level or mouth. If the unloading stations are arranged side by side along the whole fixed path, as is generally the case, the first station should advantageously have only one unloading mouth or level, as there would be no time to raise the belt before unloading takes place.

In the embodiment of Figures 3, 4 and 5 the conveyor surfaces are tiltable plates 12, actuated in known manner. Movement of the carriages is by means of a vertical, on edge, belt 17, to which the carriages are secured.

In this case on structure 8 is mounted a laterally projecting roller 13, sliding within guides set along the fixed path. These guides are placed one above another at different levels. Cams or switches, of known type and not shown in the drawings, engage roll 13 during movement of the carriage, drive the roll along either guide 14 and so move the conveyor surface to a suitable height for unloading.

In the embodiment of Figures 3, 4 and 5 the conveyor surfaces are tiltable plates 12, actuated in known manner. Movement of the carriages is by means of a vertical belt 17, to which the carriages are secured.

In this case on structure 8 is mounted a laterally projecting roller 13, sliding within guides set along the fixed path. These guides are placed one above another at different levels. Cams or switches, of known type and not shown in the drawings, engage roller 13 during movement of the carriage, drive the roller along either guide 14 and so move the conveyor surface to a suitable height for unloading.

In the embodiment of Figures 6 and 7 the conveyor surface is lifted by hydraulic or pneumatic means 15, whereby means 16 are lifted and make the conveyor surface tilt.

Claims

1. Apparatus for sorting items, including a plurality of conveyor surfaces for carrying items to be sorted, which conveyor surfaces are movable along a fixed path past a series of unloading stations, with- at least some of the unloading stations being in the form of a number of discharge levels or mouths located one above another and leading to separate storage containers or collectors and including means operative adjustably to position the conveyor surfaces selectively at the height of a desired discharge level or mouth, for discharge of a carried item at that level during movement of the conveyor surfaces along the fixed path.

2. Apparatus according to claim 1, wherein each conveyor surface is mounted, on a carriage, on an articulated parallelogram or lazy-tongs structure, means being provided to act upon the articulated parallelogram or lazy-tongs structure to displace the conveyor surface to a preselected height.

3. Apparatus according to claim 1, wherein each conveyor surface is mounted, on a carriage, on a telescopic structure operable to displace the conveyor surface to a preselected height.

4. Apparatus according to anyone of claims 1 to 3, wherein each conveyor surface is a continuous belt rotatably mounted on rollers.

5. Apparatus according to anyone of claims 1 to 3, wherein each conveyor surface is a tiltable plate.

6. Apparatus according to claim 1, wherein to each conveyor surface is secured projecting elements capable of sliding on guides located at different heights along the fixed path, means being provided for making the projecting elements engage one said guide or an other.

7. Apparatus according to claim 2, wherein the means for acting upon the articulated parallelogram or lazy-tongs structure is a fixedly located electric motor coupled to a screw-threaded shaft in mesh with a cursor secured to the parallelogram or lazy-tongs structure.

8. Apparatus for sorting items, substantially as hereinbefore described and as illustrated in Figures 1 and 2, Figures 3 to 5 or Figures 6 and 7 of the accompanying drawings.