Granular material delivery system with air flow limiter

• US 10,179,708 B2
• Filed: 12/28/2016
• Issued: 01/15/2019
• Est. Priority Date: 02/20/2014
• Status: Expired due to Fees

• Current Assignee: Maguire Products Incorporated
• Original Assignee: Maguire Products Incorporated
• Inventors: Maguire, Stephen B., Zinski, James
• Primary Examiner(s): Dillon, Jr., Joseph A
• Application Number:
  US15/392,650
• Publication Number:
  US 20170107064A1
• Time in Patent Office: 748 Days
• Field of Search: 406 83, 406192, 406195, 406197
• CPC Class Codes: B29C 31/002 Handling tubes, e.g. transferring between shaping stations, loading on mandrels
• CPC Class Codes: B65G 53/24 Gas suction systems
• CPC Class Codes: B65G 53/58 Devices for accelerating or decelerating flow of the materials; Use of pressure generators controlling pressure of propelling gas B65G53/66
• CPC Class Codes: B65G 53/66 Use of indicator or control devices, e.g. for controlling gas pressure, for controlling proportions of material and gas, for indicating or preventing jamming of material controlling the flow of coal firing systems C21B5/003

Abstract

Apparatus and methods for conveying granular material from a supply to receivers that retain and dispense the material when needed by process machine include a vacuum pump, an air flow limiter connected to the vacuum pump, a first conduit connecting the receivers to the air flow limiter, and a second conduit connecting the material supply to the receivers.

Claims

1. A method for vacuum powered pneumatic conveying, without central control, granular resin plastic material from a supply to receivers, comprising:

a) connecting self-contained, self-regulating air flow limiter for regulating flow rate between no flow and a preselected rate irrespective of pressure drop across the limiter, the limiter comprising a tube, a pair of open-ended tubular segments within the tube, a fixed outer tubular segment and a segment slideably axially movable along the fixed segment, a plate extending at least partially across the tube interior, positioned for contacting and limiting travel of the moveable tubular segment, the plate covering an outlet end of the movable tubular segment upon contact therewith, and a sail connected to the moveable segment, positioned in the tube upstream of the segments, the limiter maintaining flow to a preselected value, to a suction head of a vacuum pump, the flow limiter blocking flow when the preselected value is exceeded and blocking flow if vacuum draw ceases;

c) connecting the receivers to the air flow limiter, each of the receivers being self contained without connection to or receipt of electrical signals;

d) connecting a supply of granular plastic resin material to the receivers; and

e) drawing vacuum from the supply via a conduit to the receivers and from the receivers via a second conduit to a vacuum pump suction intake, the vacuum drawing the granular plastic material from the supply to the receivers; and

;

f) blocking flow when either the preselected value is exceeded or vacuum draw ceases.

2. A method for vacuum pump powered pneumatic conveying granular plastic resin material without central control from a supply to receivers comprising:

a) providing a vacuum drawing conduit connected to a suction head of a vacuum pump;

b) providing self-contained, self regulating air flow limiter for regulating flow rate between no flow and a preselected rate irrespective of pressure drop across the limiter, the limiter comprising a tube, a pair of open-ended tubular segments within the tube, a fixed outer tubular segment and a segment slideably axially movable along the fixed segment, a plate extending at least partially across the tube interior, positioned for contacting and limiting travel of the moveable tubular segment, the plate covering an outlet end of the movable tubular segment upon contact therewith, and a sail connected to the moveable segment, positioned in the tube upstream of the segments, the limiter maintaining flow to a preselected value between each receiver and the vacuum drawing conduit;

c) providing a conveying conduit between the supply and the receivers;

d) drawing vacuum from the supply via a conduit to the receivers and from the receivers via a second conduit to a vacuum pump suction intake, the vacuum drawing the granular plastic material from the supply to the receivers; and

;

e) blocking flow from an individual receiver to the second conduit when either the preselected value is exceeded at the individual receiver or vacuum draw ceases.