SYSTEM FOR AUTOMATING BLAST FURNACE SCALE CAR

• US 3,559,820 A
• Filed: 05/07/1969
• Issued: 02/02/1971
• Est. Priority Date: 05/07/1969
• Status: Expired due to Term

• Current Assignee: William A. Munson
• Original Assignee: William A. Munson
• Inventors: Munson, William A.
• Application Number:
  US04/822,491
• Time in Patent Office: 636 Days
• US Class Current: 414/21
• CPC Class Codes: C21B 7/18 Bell-and-hopper arrangements
• CPC Class Codes: G05B 19/188 characterised by special applications and not provided for in the relevant subclasses, (e.g. making dies, filament winding)
• CPC Class Codes: G05B 19/231 the positional error is used to control continuously the servomotor according to its magnitude

Abstract

Described is a system for automating scale cars of the type used to receive materials from storage hoppers, weigh those materials, and charge them into blast furnace skip cars. The system is characterized in having means for comparing electrical signals indicative of the actual position of the scale car, and the actual weight of materials charged into the scale car, with signals proportional to the desired car position and desired weight of materials to be charged. In this manner, the comparing means is effective to automatically stop the scale car at the correct bin position, open the discharge chute of the bin above the scale car until the desired weight is reached, and then move the scale car to a position beneath another bin or to a discharge position, all of this being determined by indicia on a punch card, computer program or the like which produces the aforesaid signals proportional to desired car position and weight.

Claims

1. In a system for controlling a scale car reciprocable along a track and adapted to receive materials from a storage bin positioned adjacent the track, transfer those materials to a discharge position along the track, and thereafter automatically discharge those materials at the discharge position, the combination of:

means for storing an electrical signal indicative of the position of said storage bin along said track to which the scale car is to travel;

means for producing an electrical signal which varies as a function of the actual position of said scale car along the track;

means for comparing said stored electrical signal indicative of the position of said bin with said electrical signal which varies as a function of the actual position of said scale car to derive an error signal;

means responsive to said error signal for moving said scale car to said bin such that said error signal is zero when the scale car is adjacent the bin; and

means responsive to a zero condition of said error signal for activating said bin to discharge at least a portion of its contents into the scale car.

2. In a system for controlling a scale car reciprocable along a track and adapted to receive materials from a storage bin positioned adjacent the track, transfer those materials to a discharge position along the track, and thereafter discharge those materials at the discharge position, the improvement comprising:

means for causing said scale car to move to a position along said track adjacent a storage bin;

means for activating said bin to discharge at least a portion of its contents into the scale car;

means for producing an electrical signal which varies in proportion to the actual weight of materials charged into the scale car;

means for storing an electrical signal indicative of the weight of the material which is to be charged into the scale car;

means for comparing said actual weight signal with said stored weight signal to produce an error signal when the actual and stored weight signals are not the same; and

means responsive to a zero condition of said error signal for stopping the discharge of materials from said bin into said scale car.

3. A system for controlling a scale car reciprocable along a track and adapted to receive materials from a storage bin positioned adjacent the track, transfer those materials to a discharge position along the track, and thereafter automatically discharge those materials at the discharge position, said system comprising:

means for storing electrical signal indicative of the position of said storage bin along said track to which the scale car is to travel and the weight of the material which is to be charged into the car from that bin;

means for producing an electrical signal which varies as a function of the actual position of said scale car along the track;

means for comparing said stored electrical signal indicative of the position of said bin with said electrical signal which varies as a function of the actual position of said scale car to derive a first error signal;

means responsive to said error signal for moving said scale car to said bin such that said error signal is zero when the scale car is adjacent the bin;

means responsive to a zero condition of said first error signal for activating said bin to discharge at least a portion of its contents into the scale car;

means for producing an electrical signal which varies in proportion to the actual weight of material charged into the scale car;

means for comparing said actual weight signal with said stored weight signal to produce a second error signal when the actual and stored weight signals are not the same;

means responsive to a zero condition of said second error signal for stopping the discharge of material from said bin into said scale car; and

means for thereafter moving said scale car to said discharge position and for automatically discharging said material at the discharge poSition.

4. The system of claim 3 wherein the means for producing an electrical signal which varies as a function of the actual position of the scale car along the track comprises a pulse generator adapted to produce a pulse each time the scale car moves through a predetermined distance along said track;

a counter to which pulses produced by said pulse generator are applied;

means for causing said counter to count up when the scale car moves in one direction; and

means for causing said counter to count down when the scale car moves in the opposite direction.

5. The system of claim 4 wherein said pulse generator comprises an inductive pickup mounted on said scale car and arranged in close proximity to a metallic rail extending parallel to said track;

said rail having equally spaced openings therein such that a pulse will be produced by said inductive pickup each time it passes an opening in said metallic rail.

6. The system of claim 3 wherein said signals indicative of the position of a storage bin along said track to which said scale car is to travel and the weight of the material which is to be charged in the scale car from that bin are derived from a punch card.

7. The system of claim 4 wherein said signal indicative of the position of a storage bin along said track to which said scale car is to travel comprises a plurality of digital signals and said counter produces a plurality of digital signals;

and including a digital comparator for comparing said sets of digital signals.

8. The system of claim 3 wherein there are a plurality of storage bins spaced along said track, and said storing means stores electrical signals indicative of the positions of the respective bins along said track.

9. The system of claim 8 wherein said means for moving said scale car moves the scale car to each of the bins in said plurality of bins in sequence.

10. The system of claim 3 wherein the means for activating said storage bin and for stopping the discharge of materials from said bin includes a device for opening and closing a discharge valve at the bottom of the bin.

11. The system of claim 3 wherein the means for producing an electrical signal which varies in proportion to the actual weight of material charged into the scale car includes strain gaps beneath hoppers carried on the scale car which receive materials discharged from a bin.

12. The system of claim 3 wherein the discharge position of said scale car is above one of two skip cars movable on a skip bridge leading to the top of a blast furnace.

13. The system of claim 3 wherein said scale car receives materials to be charged into a blast furnace, and wherein said means for storing electrical signals comprises a computer which also controls the operation of said blast furnace.