Conveyor overspeed-underspeed and/or slip detector

Claim 2

A speed comparitor and equipment control comprising: a. first input circuit means; b. second input circuit means; c. said first and said second input circuit means being respectively adapted to receive first and second input signals each indicative of a speed; d. signal summation circuit means, coacting with said first input circuit means and said second input circuit means, and respectively including first signal modification means and second signal modification means electrically interconnected by circuit element means to respectively receive said first and said second input signals and to modify same in selected and predetermined manners and so that respective first and second output signals are generated in such a manner that said first output signal is always negative in value with respect to said second output signal; e. said signal summation circuit means summing said first output signal and said second output signal so as to provide a summation circuit output signal; f. operational amplifier circuit means coacting with said signal summation circuit means to receive said summation circuit output signal therefrom, and electrically interconnected with amplifier circuit means to provide an amplifier circuit output signal of predetermined magnitude, but only in response to a summation circuit output signal which is positive in value; g. equipment control circuit means responsive to said amplifier circuit output signal to establish a closed equipment circuit to render operative selected equipment when electrically interconnected thereto, and to open said equipment circuit, upon failure of said operational amplifier circuit means to provide said amplifier output signal, to render said selected equipment inoperative.

Claim 3

The speed comparitor and equipment control of claim 1 wherein: a. said first signal modification circuit means is selectively variable to reduce the value of said first input signal by a predetermined amount indicative of a percentage of acceptable variance between a rate of speed represented by said second input signal and a rate of speed represented by said first input signal; b. said summation circuit output signal remaining positive and said amplifier circuit output signal maintaining said equipment circuit closed and said equipment operative as long as a predetermined differential exists between said first input signal and said second input signal that is within said percentage of acceptable variance; c. said summation circuit output signal becoming negative to cut-off said amplifier circuit output signal to open said equipment circuit and render inoperative said equipment when said predetermined differential no longer exists.

Claim 4

The speed comparitor and equipment control of claim 2 wherein: a. said first input signal is received from first signal generating means disposed for coaction with and so as to measure the speed of a moving element of bulk material moving equipment means and is indicative of the actual speed of said moving element; and b. said second input signal is derived from a reference signal source and is indicative of the desired speed for said moving element; c. said first input signal increasing in value as said speed of said moving element increases; d. said signal summation circuit means being responsive thereto to render said bulk material moving equipment means inoperative when said differential disappears indicating a predetermined and selected unacceptable percentage of overspeed for said moving element.

Claim 5

The speed comparitor and equipment control of claim 3 wherein said first signal generating means is a dc tachometer generator.

Claim 6

The speed comparitor and equipment control of claim 3 wherein said moving element is the input drive shaft to said bulk material moving equipment means.

Claim 7

The speed comparitor and equipment control of claim 2 wherein: a. said second input signal is received from second signal generating means disposed for coaction with and so as to measure the speed of moving element of bulk material conveying equipment means and is indicative of the actual speed of said moving element; and b. said first input signal is derived from a reference signal source and is indicative of the desired speed for said moving element; c. said second input signal decreasing in value as said speed of said moving element decreases, and d. said signal summation circuit means being responsive thereto to render said bulk material moving equipment means inoperative when said differential disappears indicating a predetermined and selected unacceptable percentage of underspeed for said moving element.

Claim 8

The speed comparitor and equipment control of claim 6 wherein said moving element is a driven element of said bulk material moving equipment means.

Claim 9

The speed comparitor and equipment control of claim 2 wherein: a. said first input signal is received from first signal generating means disposed for coaction with and so as to measure the speed of a first moving element of bulk material moving equipment means and is indicative of the acutal speed of said first moving element; b. said second input signal is received from second signal generating means disposed for coaction with and so as to measure the speed of a second moving element of bulk material moving equipment means and is indicative of the actual speed of said second moving element; c. said first input signal increasing in value as said speed of said first moving element increases and decreasing in value as said speed of said first moving element decreases, and said second input signal increasing in value as said speed of said second moving element increases and decreasing in value as said speed of said second moving element decreases; d. said signal summation circuit means being responsive thereto to render said bulk material moving equipment means inoperative when said differential disappears indicating a predetermined and selected unacceptable percentage differential between the speed of said first moving element and said second moving element.

Claim 10

The speed comparitor and equipment control of claim 8 wherein a said first moving element is the input drive shaft to said bulk material moving equipment means and said second moving element is a driven element of said same bulk material moving equipment means.

Claim 11

The speed comparitor and equipment control of claim 2 wherein: a. said first input signal is received from generating means disposed for coaction with and so as to measure the speed of a first moving element of first bulk material moving equipment means and is indicative of the actual speed of said first moving element; and b. said second input signal is received from second signal generating means disposed for coaction with and so as to measure the speed of a second moving element of a second bulk material moving equipment means and is indicative of the actual speed of said second moving element; and c. said first input signal changing in value as said speed of said first moving element changes in value, and said second input signal changing in value as said speed of said second moving element changes in value; d. said signal summation circuit means being responsive thereto to render said bulk material moving equipment means inoperative when said differential disappears indicating a predetermined and selected unacceptable percentage differential between the speed of said first bulk material moving equipment means and the speed of said second bulk material moving equipment means.

Claim 12

The speed comparitor and equipment control of claim 1 wherein said second signal modification circuit means is selectively variable to compensate for variances in circuit conditions and so as to render said first input signal and said second input signal equal in value when in fact they should be.

Claim 13

The speed comparitor and equipment control of claim 1 wherein said equipment control circuit means includes an emitter follower electrically connected to said operational amplifier circuit means and to a reed relay to control the operation thereof and thereby of said equipment circuit.

Claim 14

A bulk material moving system: comprising a. a plurality of bulk material moving means; b. a plurality of input drive means, their being one of said input drive means for each one of said bulk material moving means to provide motive power thereto; c. a plurality of speed comparitor and equipment control means each operative in a first condition thereof to render an associated piece of equipment operable and each operative in a second condition thereof to render an associated piece of equipment inoperative; d. a master control means interconnected to each of said speed comparitor and equipment control means and to each of said input drive means to control operation of said input drive means and thereby of said bulk material moving means depending upon said first and said second conditions of said speed comparitor and equipment control means; e. a plurality of speed responsive signal generating means each of which provides an electrical signal output indicative of the speed of a moving element when disposed for coaction with a moving element; f. selected ones of said spaced responsive signal generating means being disposed for coaction with selected ones of said input drive means to provide electrical signals indicative of the speeds of said input drive means and selected others of said speed responsive signal generating means being disposed for coaction with selected driven means disposed for coaction with selected ones of said input drive means; g. each of said speed responsive signal generating means being connected in circuit to a selected one of said speed comparitor and equipment control means to provide an input signal thereto; h. each of said input signals when so provided being summed, by circuit means included as a part of said speed comparitor and equipment control means, with either another of said input signals, or with a reference signal from a reference signal source also provided to said speed comparitor and equipment control means such that a positive sum will result in said speed comparitor and equipment control means assuming said first condition, and a negative sum will result in said speed comparitor and equipment control means assuming said second condition; i. first selectively adjustable circuit modification means included as part of each of said speed comparitor and equipment control means to receive and selectively modify first one of said input signals when so provided to said speed comparitor and equipment control means, and in such a way as to reduce the magnitude thereof with respect to a predetermined reference level to thus establish a percenage acceptable variance for the speed comparitor and equipment control means within which said first condition will obtain and beyond which said second condition will obtain; and j. second selectively adjustable circuit modification means included as part of each of said speed comparitor and equipment control means to receive and selectively modify a second one of said input signals, when so provided to said speed comparitor and equipment control means, and in such a way as to compensate for variations between circuit components to establish the level at which said second condition will obtain.

Claim 15

A bulk material moving system: comprising a. a plurality of bulk material moving means; b. a plurality of input drive means, their being one of said input drive means for each one of said bulk material moving means to provide motive power thereto; c. a plurality of speed comparitor and equipment control means each operative in a first condition thereof to render an associated piece of equipment operable and each operative in a second condition thereof to render an associated piece of equipment inoperative; d. a master control means interconnected to each of said speed comparitor and equipment control means and to each of said input drive means to control operation of said input drive means and thereby of said bulk material moving means depending upon said first and said second conditions of said speed comparitor and equipment control means; e. a plurality of speed responsive signal generating means each of which provides an electrical signal output indicative of the speed of a moving element when disposed for coaction with a moving element; f. selected ones of said spaced responsive signal generating means being disposed for coaction with selected ones of said input drive means to provide electrical signals indicative of the speeds of said input drive means and selected others of said speed responsive signal generating means being disposed for coaction with selected driven means disposed for coaction with selected ones of said input drive means; g. each of said speed responsive signal generating means being connected in circuit to a selected one of said speed comparitor and equipment control means to provide an input signal thereto; h. each of said input signals when so provided being summed, by circuit means included as a part of said speed comparitor and equipment control means, with either another of said input signals, or with a reference signal from a reference signal source also provided to said speed comparitor and equipment control means such that a positive sum will result in said speed comparitor and equipment control means assuming said first condition, and a negative sum will result in said speed comparitor and equipment control means assuming said second condition; i. first selectively adjustable circuit modification means included as part of each of said speed comparitor and equipment control means to receive and selectively modify first one of said input signals when so provided to said speed comparitor and equipment control means, and in such a way as to reduce the magnitude thereof with respect to a predetermined reference level to thus establish a percenage acceptable variance for the speed comparitor and equipment control means within which said first condition will obtain and beyond which said second condition will obtain; and j. second selectively adjustable circuit modification means included as part of each of said speed comparitor and equipment control means to receive and selectively modify a second one of said input signals, when so provided to said speed comparitor and equipment control means, and in such a way as to compensate for variations between circuit components to establish the level at which said second condition will obtain.

Claim 16

The bulk material moving system of claim 13 wherein said speed responsive signal generating means are dc tachometer generators.

Claim 17

The bulk material moving system of claim 13 wherein said selectively adjustable circuit modification means are potentiometers.

Claim 18

The bulk material moving system of claim 13 wherein a. at least one of said bulk material moving means is a bulk material conveyor; b. a first speed comparitor and equipment control means is operatively associated with said bulk material conveyor to compare the speed of said input drive to said conveyor with a predetermined reference level speed and so that said speed comparitor and equipment control means assumes said second condition in response to an overspeed condition for said bulk material conveyor; c. a second speed comparitor and equipment control means is operatively associated with said bulk material conveyor to compare the speed of a driven element of said bulk material conveyor with the speed of said input drive to said bulk material conveyor and so that said speed comparitor and equipment control means assumes said second condition in response to an excessive difference between said input drive speed and said speed of said driven element of said bulk material conveyor; d. a second one of said bulk material moving means is a bulk material elevator coacting with and driven by said bulk material conveyor and disposed to receive material therefrom; and e. a third said speed comparitor and equipment control means is operatively associated with said bulk material elevator to compare the speed of a driven element of said bulk material elevator with the speed of said driven element of said bulk material conveyor and so that said speed comparitor and equipment control means assume said second condition in response to an excessive difference between said speed driven element of said bulk material elevator and said driven element of said bulk material conveyor.