GB2236595A

GB2236595A - Sorting by weighing

Info

Publication number: GB2236595A
Application number: GB9016841A
Authority: GB
Inventors: Alan Peebles
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-08-01
Filing date: 1990-08-01
Publication date: 1991-04-10
Anticipated expiration: 2010-08-01
Also published as: GB8917598D0; GB9016841D0; GB2236595B

Abstract

Items e.g. baked potatoes 3 are fed from storage container 2 to a hopper 4 and transported upwards by a roller table 5 therein which singles them out, to a compartmented conveyor 6, 7, which drops them one at a time into an air cushioned weigh bucket 8, where they are weighed instantaneously one at a time and then delivered to a respective weight range container 13. Weigh bucket 8 is attached to an electronic load cell assembly 9 which classifies the items into a lower weight range i.e. underweights and up to 10oz and an upper weight range i.e. 10oz and upwards, and opens respective flaps 10 at the bottom of the bucket to deliver the items to one or other side of a conveyor 11 for delivery to appropriate weight range container 13. The machine operates automatically. <IMAGE>

Description

"Weighing Apparatus" This invention relates to weighing apparatus, in particular to weighing apparatus for vegetables such as potatoes.

Existing machines for weighing potatoes are large mechanical apparatus, some over 100 feet long, which are limited in that none are specifically designed for baked potato weighing.

As such, these machines are mechanically intensive with outputs of up to three tons an hour, and give a rough rather than accurate guide to any particular potato's weight.

Some are totally mechanical with a series of weight trays which are tripped mechanically under pressure from the potato above. Others have electronic load cells where the load is actually dragged over the load cells and weighed whilst in motion. This takes an average weight over the load cell.

All the machines cost between 35,000 and 150,000 each and do not weigh potatoes accurately on an individual basis.

The present invention has been designed to mitigate some of these problems and to classify potatoes into various weight ranges for the baked potato market and to divert those potatoes which are underweight or overweight into separate lots.

According to the present invention there is provided weighing apparatus for grading items by weight, comprising a separating means, an electronically controlled weighing and grading means and collecting means, the whole providing an automated route along which an item is conveyed and graded.

Preferably said separating means comprises a holder in which the supply of items is held, a hopper and a roller table, connected so that as the hopper is filled from the holder with items to be weighed, such as potatoes, the roller table separates these out into single items.

The roller table may then deposit each item onto a compartmented conveyor which conveys its load to the weighing and grading means.

Said weighing and grading means is-preferably provided by an air-cushioned bucket which is attached to a load cell assembly, controlled by a microprocessor program.

The grading means may be provided by the bucket being shaped so that it directs each item, according to weight, through a defined aperture, and onto the collecting means, As the items drop into the bucket they may be weighed by the load cell and graded according to their weight.

The load cell may be programmed to categorize the items in a range of weights, or to accurately weigh each item.

The collecting means preferably comprises a conveyor which directs the weighed item into an appropriate container; either by plough flaps which close along the path of the item, or by providing a series of conveyors and containers one for each weight grade provided.

An embodiment of the invention will now be described with reference to the drawings in which: Fig. 1 is a schematic side view of the weighing apparatus of the present invention; and Fig.2 is a plan view of part of the weighing apparatus of Fig.l.

A weighing apparatus 1 comprises a holder 2 in which potatoes 3 are stored and from which they are fed, either manually or mechanically, into a hopper 4. The hopper 4 contains a roller table 5 which pulls the potatoes upwards and singles them out so that each potato in turn falls onto a horizontal compartmented conveyor, eg a flighted conveyor 6 which has raised cleats that form compartments 7. Each potato is caught in a compartment 7 and pulled along the conveyor. The roller table 5 and flighted conveyor 6 are synchronised by a combi box (not shown) ie a brake and clutch mechanism which allows the motor to run continuously whilst at the same time synchronising the movements.

From the conveyor 6, the potatoes drop individually into an air-cushioned bucket 8 (the air-cushion absorption is built into a cylinder under flaps). The bucket 8 is attached to an electronic load cell assembly 9, and the potatoes are weighed instantaneously as they drop into the bucket 8 at a maximum rate of 2/sec. The bucket 8 has flaps 10 positioned above a product conveyor 11. The microprocessor classifies the weights into the lower weight range ie underweights and up to 10or, on one side of the bucket 8, and 10oz and upwards on the other side, and opens one of the two flaps 10 on the bucket.The conveyor 11 has plough flaps 12 that close across the path of the on-coming potato, and divert it off the conveyor 11 into the appropriate range container 13, or alternatively, the potato is allowed to pass along to the end of the conveyor 11 if over- or under-weight.

The individual weight of the potato could be used as part of the procedure following the weighing but in the design of this machine the microprocessor connected to the load cell assembly 9 is programmed to categorize the weights into the following categories: 6-80z, 8-lOoz, 10-1202 and 12-140z.

For the purposes of baked potatoes the categories are limited to six (including under/over weights).

The limitations of the number of ranges has been brought into the design because of the requirements of the baked potato trade. The design could incorporate an almost limitless number of weight ranges or could be used to accurately weigh each individual potato. Indeed, although the machine has been designed for potatoes it could be used to either classify, by weight ranges or weighing individually, either fruit or vegetables or any other items including manufactured items which require to be classified or weighed.

It should be noted that the microprocessor can keep a tally of individual weights and numbers falling into different categories. With a more sophisticated program it could be used to classify by number and weight range e.g. 3 potatoes with a total weight of 240zs plus or minus a given percentage.

The overall size of the machine is approximately 12 feet long (from the hopper to the end of classified product conveyor as described above) and approximately 2 feet wide.

The output conveyor is approximately 30 inches high to ground level with the flighted conveyor approximately 1 foot higher and the roller table rising from roughly the same height as the output conveyor to just above the flighted conveyor. It is believed that a reasonable output from the machine would be three-quarters of a ton of potatoes per hour with a maximum of one ton per hour.

It is anticipated that the cost of the machine would be 10,000-12,000, which is a far more economical outlay than those at present available.

Modifications and improvements may be incorporated without departing from the scope of the invention.

Claims

1 Weighing apparatus for grading items by weight, comprises a separating means, an electronically controlled weighing and grading means and collecting means, the whole providing an automated route along which an item is conveyed and graded.

2 Apparatus as claimed in Claim 1, wherein said separating means comprises a holder in which the supply of items is held, a hopper and a roller table, connected so that as the hopper is filled from the holder with items to be weighed, such as potatoes, the roller table separates these out into single items.

3 Apparatus as claimed in Claim 2, wherein the roller table deposits each item onto a compartmented conveyor which conveys its load to the weighing and grading means.

4 Apparatus as claimed in Claim 1, wherein said weighing and grading means is provided by an air-cushioned bucket which is attached to a load cell assembly, controlled by a microprocessor program.

5 Apparatus as claimed in Claim 4, wherein the grading means provided by the bucket being shaped so that it directs each item, according to weight, through a defined aperture, and onto the collecting means.

6 Apparatus as claimed in Claim 4, wherein the load cell is programmed to categorize the items in a range of weights.

7 Apparatus as claimed in Claim 4, wherein the load cell is programmed to accurately weigh each item.

8 Apparatus as claimed in Claim 1, wherein the collecting means comprises a conveyor which directs the weighed item into an appropriate container by plough flaps which close along the path of the item.

9 Apparatus as claimed in Claim 1, wherein the collecting means comprises a conveyor which directs the weighed item into an appropriate container by providing a series of conveyors and containers, one for each weight grade provided.

10 Apparatus substantially as hereinbefore described with reference to the accompanying drawings.