Sorting machine

• US 20030201211A1
• Filed: 08/23/2002
• Published: 10/30/2003
• Est. Priority Date: 08/24/2001
• Status: Active Grant

• Current Assignee: Attica Automation Incorporated
• Original Assignee: Attica Automation Incorporated
• Inventors: Bennett, William H., Hurttgam, Christopher P.
• Granted Patent: US 6,787,724 B2
• Time in Patent Office: Days
• US Class Current: 209/586
• CPC Class Codes: B07C 5/10 measured by light-responsive means sorting according to colour B07C5/342
• CPC Class Codes: Y10S 209/904 Feeder conveyor holding item by magnetic attraction
• CPC Class Codes: Y10S 209/907 Magnetic feeder
• CPC Class Codes: Y10S 209/922 Miscellaneous feed conveyors
• CPC Class Codes: Y10S 209/923 Feed through including at least one endless conveyor
• CPC Class Codes: Y10S 209/929 Fastener sorter

Abstract

A sorting machine receives a bulk of workpieces or fasteners from a hopper unit into a feed station which align the fasteners into a single file for engagement to a transport system of an inspection station. Preferably, the transport system has a conveyor belt with a magnetic member disposed radially inward from the belt. The fasteners are preferably ferrous and thereby engage the conveyor belt via the magnetic field which penetrates the belt. The fasteners are thus carried along the transport system past a trigger sensor which sends a signal to a central controller to timely actuate a dimensional sensing apparatus which takes an image of the fastener and sends it to the central computer for dimensional analysis. If the fastener fails to meet pre-established guidelines the nonconforming fastener is ejected from the transport system via a reject mechanism. If the fastener conforms, it continues to move along the transport system, past a counter sensor and is then dropped off the conveyor belt of the transport system into a packaging station for ultimate delivery to the customer.

Claims

1. A sorting machine for inspecting and sorting a workpiece, the sorting machine comprising:

a central controller;

a hopper unit for bulk storage of a plurality of workpieces;

a feed station having a distribution assembly and a belt drive system, wherein the plurality of workpieces loosely fall from the hopper unit into the distribution assembly and wherein the belt drive system receives the plurality of workpieces in an orderly fashion from the distribution assembly;

an inspection station having a variable speed transport system, a trigger sensor, a dimensional sensing apparatus, and a reject mechanism, wherein the transport system receives the plurality of workpieces one-by-one in a linear fashion and each respective one of the workpieces travel via the transport system past the trigger sensor which sends a signal to the controller to actuate the dimensional sensing apparatus disposed along the transport system and between the trigger sensor and the reject mechanism; and

wherein the central controller receives a dimension signal from the sensing apparatus and activates the reject mechanism to remove the respective one of the plurality of workpieces from the transport system if the respective one of the plurality of workpieces is nonconforming.

2. The sorting machine set forth in claim 1 comprising:

each one of the plurality of workpieces having an elongated shank and a head projecting radially outward from one end of the shank;

wherein the head of each one of the plurality of workpieces is made of a ferrous material; and

the transport system having an elongated conveyor belt and a magnetic member constructed and arranged to hold the ferrous head of the workpiece against the conveyor belt.

3. The sorting machine set forth in claim 2 wherein the magnetic member is stationary and is disposed radially inward from and directly adjacent to the conveyor belt of the transport system.

4. The sorting machine set forth in claim 3 wherein the magnetic member has a plurality of magnets aligned side by side in a linear fashion, and wherein the magnets located adjacent to the reject mechanism have a weaker pull strength than the remaining magnets of the plurality of magnets.

5. The sorting machine set forth in claim 2 wherein the plurality of workpieces are suspended from the conveyor belt of the transport system via the magnetic field of the magnetic member.

6. The sorting machine set forth in claim 5 wherein the dimensional sensing apparatus has a back light positioned on one lateral side of the transport system and a camera positioned on an opposite side of the transport system.

7. The sorting machine set forth in claim 1 wherein the reject mechanism is a flipper mechanism having a paddle which physically knocks the nonconforming workpiece of the plurality of workpieces away from the transport system.

8. The sorting machine set forth in claim 5 wherein the reject mechanism is a electromagnet interposing the magnetic member, and which is de-energized by the controller to reject an adjacent nonconforming workpiece of the plurality of workpieces.

9. The sorting machine set forth in claim 5 wherein the reject mechanism has a constant magnet that interposes the magnet member and a solenoid constructed and arranged to move the constant magnet toward and away from the conveyor belt of the transport system upon initiation via the controller.

10. The sorting machine set forth in claim 5 comprising:

the belt drive system of the feeder station being a dual belt drive system having two parallel elongated conveyor belts spaced apart by a distance slightly greater than a diameter of the shank and slightly less than the diameter of the head of each one of the plurality of workpieces;

each one of the two conveyor belts of the dual belt drive system having an upward facing surface;

each head of the plurality of workpieces having a downward facing annular surface capable of resting upon both conveyor belts of the belt drive system so that the workpiece suspends from the upward facing surfaces; and

wherein a distal end portion of the dual belt drive system is disposed under an end of the transport system and spaced at a distance slightly greater than a height of each head of the plurality of workpieces.

11. The sorting machine set forth in claim 10 wherein the dual belt drive system has a single variable speed motor for driving both conveyor belts of the belt drive system.

12. The sorting machine set forth in claim 10 wherein the distal end portion of the dual belt drive system is made of a non-ferrous material.

13. The sorting machine set forth in claim 1 comprising:

a base of the feed station;

the distribution assembly of the feed station being a vibrating container assembly having a bowl, a vibrating mechanism engaged rigidly to the base and constructed and arranged to impact the bowl at a vibration inducing frequency, a spiraling shelf projecting radially inward from a cylindrical wall of the bowl and extending upward from a bottom of the bowl, and a pair of parallel rails engaged rigidly to an exterior of the bowl near an upward end of the shelf;

wherein the distance between the parallel rails is substantially equal to the distance between the two belts of the dual belt drive system; and

wherein vibration of the bowl causes the plurality of workpieces disposed within the bowl to move circumferentially upwardly within the bowl along the shelf and into, thus suspended by, the pair of parallel rails.

14. The sorting machine set forth in claim 5 wherein the hopper unit has a hopper which carries a lower opening, a tray disposed adjacent to the opening, and a vibration mechanism constructed and arranged to vibrate the tray inducing the plurality of workpieces disposed within the hopper to drop into the distribution assembly.

15. The sorting machine set forth in claim 14 wherein the distribution assembly of the feed station has a pair of elongated counter rotating rollers which suspend each one of the plurality of workpieces by the head.

16. The sorting machine set forth in claim 15 wherein the pair of counter rotating rollers are slightly slanted downward toward the transport system of the inspection station.

17. The sorting machine set forth in claim 16 wherein the pair of counter rotating rollers is one of a plurality of pairs of counter rotating rollers aligned side-by-side to one another and separated laterally by an inverted V-shaped guide plate for guiding the workpieces between the counter rotating rollers of each pair of the plurality of pairs of counter rotating rollers.

18. The sorting machine set forth in claim 17 wherein the plurality of workpieces fall loosely from the vibrating tray of the hopper unit into the plurality of pairs of counter rotating rollers disposed below the tray.

19. The sorting machine set forth in claim 18 comprising:

the belt drive system of the feeder station having a plurality of dual belt drive systems each having two parallel elongated conveyor belts spaced apart by a distance slightly greater than a diameter of the shank and slightly less than the diameter of the head of each one of the plurality of workpieces;

each one of the two conveyor belts of the dual belt drive system having an upward facing surface;

each head of the plurality of workpieces having a downward facing annular surface capable of resting upon both conveyor belts of the belt drive system so that the workpiece suspends from the upward facing surfaces;

wherein a distal end portion of each one of the plurality of dual belt drive systems is disposed under a respective end of each one of the plurality of transport systems and spaced at a distance slightly greater than a height of each head of the plurality of workpieces; and

wherein each one of the plurality of pairs of counter rotating rollers is align to a respective one of the plurality of dual belt drive systems.

20. The sorting machine set forth in claim 2 wherein the heads of the plurality of workpieces rest upon an upward facing surface of the conveyor belt of the transport system and the shanks project upward from the heads.