Combination weigher with peripheral annular recycling table

• US 7,790,990 B2
• Filed: 10/30/2008
• Issued: 09/07/2010
• Est. Priority Date: 10/30/2008
• Status: Active Grant

• Current Assignee: Yamato Corp.
• Original Assignee: Yamato Corp.
• Inventors: Kieselhorst, Ralph
• Primary Examiner(s): Gibson; Randy W
• Application Number:
  US12/261,836
• Publication Number:
  US 20100108404A1
• Time in Patent Office: 677 Days
• Field of Search: 177/25.18, 177/90, 177/91
• US Class Current: 177/25.18
• CPC Class Codes: G01G 19/393 using two or more weighing units

Abstract

A combination weigher of the present invention comprises a plurality of weighing hoppers which are arranged in a circular shape and are each configured to discharge the products selectively in one of two directions, a collecting chute which is configured to gather the products which have been discharged from the weighing hopper in the inward direction and to discharge the products, a recycle conveyor configured to convey the products which have been discharged from the weighing hoppers in the outward direction and have been loaded onto the recycle conveyor, a discharge means which is configured to discharge the products from the recycle conveyor; a combination calculation means which is configured to determine a discharge combination, a recycle hopper determination means configured to determine a weighing hopper whose products should be recycled, and a control means configured to cause the weighing hoppers selected to form the discharge combination to discharge the products in the inward direction, and to cause the weighing hopper determined by the recycle hopper determination means to discharge the products in the outward direction.

Claims

1. A combination weigher comprising:

a plurality of weighing hoppers which are arranged in a circular shape and are each configured to hold products, and then to discharge the products selectively in an inward direction of the circular shape or in an outward direction of the circular shape, the weighing hoppers being each configured to measure weight of the products which are held therein;

a collecting chute which is positioned below the weighing hoppers, the collecting chute being configured to collect the products which have been discharged from the weighing hopper in the inward direction and to discharge the products from a discharge outlet at a bottom part thereof;

a recycle conveyor which is positioned below the weighing hoppers so as to surround the collecting chute, the recycle conveyor being configured to convey, in one direction around the collecting chute, the products which have been discharged from the weighing hopper in the outward direction and have been loaded onto the recycle conveyor;

a discharge means which is configured to discharge the products on the recycle conveyor in a predetermined position from the recycle conveyor;

a combination calculation means which is configured to determine a discharge combination which is a combination of weighing hoppers holding the products whose total weight falls within a predetermined weight range;

a recycle hopper determination means configured to determine a weighing hopper whose products should be recycled, based on a predetermined recycle condition; and

a control means configured to cause the weighing hoppers selected to form the discharge combination to discharge the products in the inward direction, and to cause the weighing hopper determined by the recycle hopper determination means to discharge the products in the outward direction, and

wherein the recycle conveyor includes an annular rotary table onto which the products are loaded, the rotary table being rotatable around a vertical axis extending through a center of the circular shape in which the weighing hoppers are arranged; and

wherein the discharge means includes a guide plate which guides, to outside the rotary table, the products on the rotary table which is rotating.

2. The combination weigher according to claim 1, further comprising:

a dispersion feeder configured to disperse the products which have been supplied to a center portion thereof toward a peripheral edge thereof;

a plurality of linear feeders which are arranged radially around the dispersion feeder, the linear feeders being each configured to convey, in a direction away from the dispersion feeder, the products which have been fed from the dispersion feeder, and to discharge the products;

a plurality of feeding hoppers which are arranged in a circular shape above the weighing hoppers, and are configured to hold the products which have been discharged from the linear feeders and to then feed the products to the weighing hoppers; and

a transport means of the products which is configured to feed, to the dispersion feeder, the products which have been discharged from the recycle conveyor by the discharge means.

3. The combination weigher according to claim 1, further comprising:

an inner guide plate which is configured to guide, to an inner edge portion of the rotary table, the products which have been discharged from the weighing hoppers in the outward direction.

4. The combination weigher according to claim 1, further comprising:

an outer guide plate provided to extend along an outer edge portion of the rotary table.

5. The combination weigher according to claim 1, wherein the predetermined recycle condition is such that a weight of the products which are held in the weighing hopper has a predetermined weight value or larger which is larger than a target feed amount for the weighing hopper.

6. The combination weigher according to claim 1, wherein the predetermined recycle condition is such that a weight of the products which are held in the weighing hopper has a value that is larger than an upper limit value in the predetermined weight range.

7. The combination weigher according to claim 1, wherein

the combination calculation means is configured to determine a discharge combination which is a combination of the weighing hoppers which hold the products whose total weight falls within a predetermined weight range and whose total number is a target number;

and

wherein the recycle hopper determination means is configured to determine that the predetermined recycle condition is such that the number of the products which are held in the weighing hopper is a predetermined number or larger.

8. The combination weigher according to claim 1, wherein

the combination calculation means is configured to determine a discharge combination which is a combination of the weighing hoppers which hold the products whose total weight falls within a predetermined weight range and which hold the products whose total number is a target number;

and

wherein the recycle hopper determination means is configured to determine that the predetermined recycle condition is such that the number of the products which are held in the weighing hopper is larger than the target number.

9. The combination weigher according to claim 1, wherein

the predetermined recycle condition is such that the weighing hopper is not selected for the discharge combination during a predetermined time period or longer.