Belt fissure detection device

Claim 2

A belt fissure detection apparatus comprising a plurality of pairs of first and second loop coils embedded in a conveyor belt and disposed at suitable intervals over the entire length of said belt, said first loop coil extended in the longitudinal direction of said conveyor belt and adjacent to and along one edge of said conveyor belt and said second loop coil extended in a direction at right angles relative to said first loop coil, one end of said second loop coil being overlapped by a corresponding end of said first loop coil adjacent to said conveyor belt edge, and excitor coil connected to an oscillating current source and positioned in proximity to said overlapped loop coil ends of said first and second loop coils, a pair of receiver coils connected to respective terminals of a belt fissure detector circuit and positioned in proximity to the other ends of said first and second loop coils, the arrangement of all of said coils being such that, when said overlapped loop coil ends travel in proximity near said excitor coil as said conveyor belt is being driven, said other loop coil ends at the same time travel in proximity with respective of said receiver coils to provide an electromagnetic coupling circuit between said excitor coil and said receiver coils through said loop coils to produce a pair of electrical signals whereby the occurrence of a fissure in said conveyor belt can be detected by said detector circuit.

Claim 3

The belt fissure detection apparatus of claim 1 wherein said electric signals received by said receiver coils are respectively applied to an ''''OR'''' circuit and an ''''AND'''' circuit, in said detector circuit the output signal of said OR circuit being applied to a set terminal of a bistable flip-flop circuit while the output signal of said AND circuit applied to a reset terminal of said bistable flip-flop circuit through a delay circuit, the output signal of said flip-flop circuit being representative of a breakage of any one of said loop coils embedded in said conveyor belt.

Claim 4

The belt fissure detection apparatus of claim 1, wherein each of said loop coils embedded in said conveyor belt comprises a wiring element consisting of a resilient fiber core and a fine conductive wire in the form of strip or foil spirally wound around said core.

Claim 5

The belt fissure detection apparatus of claim 1, wherein each of said loop coils embedded in said conveyor belt comprises a wiring element consisting of two lengths of twisted fine conductive wire in the form of strip or foil spirally wound around a resilient fiber core.

Claim 6

The belt fissure detection apparatus of claim 1, wherein each of the loop coils comprises a wiring element consisting of a resilient fiber core and a plurality of fine conductive wires in the form of a foil spirally wound around said core, said plurality of wires being arranged in parallel alignment and bound together by shoot yarns to provide a band.

Claim 7

The belt fissure detection apparatus of claim 1, wherein each of said receiver coils or said excitor coil comprises a primary winding formed around a ferrite core and a secondary winding formed around said ferrite core adjacent said primary winding, said secondary coil winding forming a resonance circuit in resonance with the excitor frequency imposed upon said primary coil.

Claim 8

A belt fissure detection apparatus comprising a plurality of pairs of first and second loop coils embedded in a conveyor belt and disposed at suitable intervals over the entire length of said belt, said first loop coil extended in the longitudinal direction of said conveyor belt and adjacent to and along one edge of said conveyor belt and said second loop coil extended in a direction at right angles relative to said first loop coil, one end of said second loop coil being adjacently spaced from a corresponding end of said first loop coil an excitor coil connected to an oscillating current source and positioned in proximity to both of said spaced loop coil ends of said first and second loop coils, a pair of receiver coils connected to respective terminals of a belt fissure detector circuit and positioned in proximity to the other ends of said first and second loop coils, the arrangement of all of said coils being such that, when said spaced loop coil ends travel in proximity near said excitor coil as said conveyor belt is being driven, said other loop coil ends at the same time travel in proximity with respective of said receiver coils to provide an electromagnetic coupling circuit between said excitor coil and said receiver coils through said loop coils, whereby the occurrence of a fissure in said conveyor belt can be detected by said detector circuit.

Claim 9

A belt fissure detection apparatus comprising a plurality of pairs of first and second loop coils embedded in a conveyor belt and disposed at suitable intervals over the entire length of said belt, said first loop coil extended in the longitudinal direction of said conveyor belt and adjacent to and along one edge of said conveyor belt and said second loop coil extended in a direction at right angles relative to said first loop coil, one end of said second loop coil being adjacently spaced from a corresponding end of said first loop coil an excitor coil connected to an oscillating current source and positioned in proximity to both of said spaced loop coil ends of said first and second loop coils, a pair of receiver coils connected to respective terminals of a belt fissure detector circuit and positioned in proximity to the other ends of said first and second loop coils, the arrangement of all of said coils being such that, when said spaced loop coil ends travel in proximity near said excitor coil as said conveyor belt is being driven, said other loop coil ends at the same time travel in proximity with respective of said receiver coils to provide an electromagnetic coupling circuit between said excitor coil and said receiver coils through said loop coils, whereby the occurrence of a fissure in said conveyor belt can be detected by said detector circuit.

Claim 10

A belt fissure detection apparatus comprising a plurality of pairs of first and second loop coils embedded in a conveyor belt and disposed at suitable intervals over the entire length of said belt, said first loop coil first extended in the longitudinal direction of said conveyor belt and adjacent to and along one edge of said conveyor belt and said second loop coil extended in a direction at right angles relative to said first loop coil, one end of said second loop coil being adjacently spaced from a corresponding end of said first loop coil, an excitor coil capable of generating two electrical signals of different frequencies and positioned in proximity to said adjacently spaced first and second loop coil ends, a pair of receiver coils connected to respective terminals of a fissure detector circuit and positioned in proximity to the other ends of said first and second loop coils, the arrangement of all said coils being such that, when said adjacently spaced loop coil ends travel in proximity to said excitor coil as said conveyor belt is driven, said other loop coil ends at the same time travel in proximity with respectiVe of said receiver coils to provide an electromagnetic coupling circuit between said excitor coil and said receiver coils through said loop coils, whereby signals received by said receiver coils are applied to circuit filter means for discriminating between said signals due to different frequencies and thereafter applied to respective terminals of said detector circuit.

Claim 11

A belt fissure detection apparatus comprising a plurality of pairs of first and second loop coils embedded in a conveyor belt and disposed at suitable intervals over the entire length of said belt, said first loop coil first extended in the longitudinal direction of said conveyor belt and adjacent to and along one edge of said conveyor belt and said second loop coil extended in a direction at right angles relative to said first loop coil, one end of said second loop coil being adjacently spaced from a corresponding end of said first loop coil, an excitor coil capable of generating two electrical signals of different frequencies and positioned in proximity to said adjacently spaced first and second loop coil ends, a pair of receiver coils connected to respective terminals of a fissure detector circuit and positioned in proximity to the other ends of said first and second loop coils, the arrangement of all said coils being such that, when said adjacently spaced loop coil ends travel in proximity to said excitor coil as said conveyor belt is driven, said other loop coil ends at the same time travel in proximity with respectiVe of said receiver coils to provide an electromagnetic coupling circuit between said excitor coil and said receiver coils through said loop coils, whereby signals received by said receiver coils are applied to circuit filter means for discriminating between said signals due to different frequencies and thereafter applied to respective terminals of said detector circuit.

Claim 12

A belt fissure detection apparatus comprising a pair of loop coils embedded in a conveyor belt, one of said coils extended in the longitudinal direction of said belt and adjacent to and along one edge of said belt, the other of said coils extended in a direction transverse to the longitudinal direction of said belt and having one end in overlapped relationship with one end of the first-mentioned loop coil, a second pair of loop coils embedded in said belt at a position adjacent to the first-mentioned pair of loop coils, one of said coils of said second loop coil pair extended in the longitudinal direction of said belt, the other of said coils of said second loop coil pair extended in a direction transverse to the longitudinal direction of said belt and having one end in overlapped relationship with one end of the first-mentioned loop coil of said second loop coil pair, excitor coils each capable of generating an electric signal of oscillating current and each respectively positioned in proximity to one of said overlapped ends of said first and second loop coil pairs, two pairs of receiver coils, each pair connected to respective terminals of a fissure detector circuit and each respectively positioned in proximity to the other ends of said loop coils of each of said loop coil pairs, the arrangement of all of said coils being such that, when said overlapped loop coil ends of each of said loop coil pairs travel in proximity near their respective excitor coil as said conveyor belt is driven, said other ends of said loop coils of each of said loop coil pairs at the same time travel in proximity to their respective receiver coils to provide an electromagnetic coupling circuit between each of said excitor coils and each of said receiver coils whereby the occurrence of a fissure in said conveyor belt can be detected by said detector circuit.

Claim 13

A belt fissure detection apparatus comprising a pair of loop coils embedded in a conveyor belt, one of said coils extended in the longitudinal direction of said belt and adjacent to and along one edge of said belt, the other of said coils extended in a direction transverse to the longitudinal direction of said belt and having one end in overlapped relationship with one end of the first-mentioned loop coil, a second pair of loop coils embedded in said belt at a position adjacent to the first-mentioned pair of loop coils, one of said coils of said second loop coil pair extended in the longitudinal direction of said belt, the other of said coils of said second loop coil pair extended in a direction transverse to the longitudinal direction of said belt and having one end in overlapped relationship with one end of the first-mentioned loop coil of said second loop coil pair, excitor coils each capable of generating an electric signal of oscillating current and each respectively positioned in proximity to one of said overlapped ends of said first and second loop coil pairs, two pairs of receiver coils, each pair connected to respective terminals of a fissure detector circuit and each respectively positioned in proximity to the other ends of said loop coils of each of said loop coil pairs, the arrangement of all of said coils being such that, when said overlapped loop coil ends of each of said loop coil pairs travel in proximity near their respective excitor coil as said conveyor belt is driven, said other ends of said loop coils of each of said loop coil pairs at the same time travel in proximity to their respective receiver coils to provide an electromagnetic coupling circuit between each of said excitor coils and each of said receiver coils whereby the occurrence of a fissure in said conveyor belt can be detected by said detector circuit.

Claim 14

A belt fissure detection apparatus comprising a plurality of loop coil members each of quadrangular configuration and together comprising one unit embedded in a conveyor belt and disposed at suitable intervals over the entire length of said belt, the first member of said loop coils including a pair of coil sides extending in the longitudinal direction of said belt in spaced parallel relation to each other and a second pair of the coil sides extending in a direction transverse of the longitudinal direction of said belt, the second member of said loop coils including a pair of coil sides extending in the longitudinal direction of said belt in spaced parallel relation to each other, one of said coil sides in spaced parallel and adjacent relation to one of the longitudinal coil sides of said first member, and a second pair of coil sides extending in a direction transverse of the longitudinal direction of said belt, the third member of said loop coils positioned longitudinally adjacent to said first and second members and including a pair of coil sides extending in the longitudinal direction of said belt in spaced parallel relation to each other, and a pair of coil sides extending in a direction transverse of the longitudinal direction of said belt in spaced parallel and adjacent relation to each other and with one transverse coil sides of each of said first and second members, a pair of excitor coils connected to an oscillating current source and respectively positioned in proximity to said parallel, adjacent transverse sides of said first member, said second member and said third member, a receiver coil positioned in proximity with each of the other transverse sides of said first, second and third members, and connected to a belt fissure detector circuit, wherebY the occurrence of a fissure in said conveyor belt can be detected by said detector circuit.

Claim 15

A belt fissure detection apparatus comprising a plurality of loop coil members each of quadrangular configuration and together comprising one unit embedded in a conveyor belt and disposed at suitable intervals over the entire length of said belt, the first member of said loop coils including a pair of coil sides extending in the longitudinal direction of said belt in spaced parallel relation to each other and a second pair of the coil sides extending in a direction transverse of the longitudinal direction of said belt, the second member of said loop coils including a pair of coil sides extending in the longitudinal direction of said belt in spaced parallel relation to each other, one of said coil sides in spaced parallel and adjacent relation to one of the longitudinal coil sides of said first member, and a second pair of coil sides extending in a direction transverse of the longitudinal direction of said belt, the third member of said loop coils positioned longitudinally adjacent to said first and second members and including a pair of coil sides extending in the longitudinal direction of said belt in spaced parallel relation to each other, and a pair of coil sides extending in a direction transverse of the longitudinal direction of said belt in spaced parallel and adjacent relation to each other and with one transverse coil sides of each of said first and second members, a pair of excitor coils connected to an oscillating current source and respectively positioned in proximity to said parallel, adjacent transverse sides of said first member, said second member and said third member, a receiver coil positioned in proximity with each of the other transverse sides of said first, second and third members, and connected to a belt fissure detector circuit, wherebY the occurrence of a fissure in said conveyor belt can be detected by said detector circuit.

Claim 16

A belt fissure detection apparatus comprising a plurality of pairs of first and second loop coils embedded in a conveyor belt and disposed at suitable intervals over the entire length of said belt, said first loop coil of each of said pairs extended in the longitudinal direction of said conveyor belt and adjacent to and along one edge of said conveyor belt and said second loop coil of each of said pairs extended in a direction at right angles relative to said first loop coil, one end of said second loop coil being adjacently spaced from a corresponding end of said first loop coil, a carriage having wheel means rotatable on a pair of rails positioned in a direction normal to the longitudinal direction of said belt, a pair of vertical support shafts for each of said carriages, a guide roller rotatably mounted on the end of each of said support shafts to engage a respective edge of said conveyor belt, tie rod means to couple said carriages together, said carriages having mounted thereon an excitor coil and a pair of receiver coils in aligned relationship to said loop coils, said receiving coils capable of receiving respective signals from said excitor coil through the loop coils, and a fissure detector signal connected to said receiver coils and responsive to said signals therefrom indicative of the occurrence of fissure in said conveyor belt.

Claim 17

A belt fissure detection apparatus comprising a plurality of pairs of first and second loop coils embedded in a conveyor belt and disposed at suitable intervals over the entire length of said belt, said first loop coil of each of said pairs extended in the longitudinal direction of said conveyor belt and adjacent to and along one edge of said conveyor belt and said second loop coil of each of said pairs extended in a direction at right angles relative to said first loop coil, one end of said second loop coil being adjacently spaced from a corresponding end of said first loop coil, a carriage having wheel means rotatable on a pair of rails positioned in a direction normal to the longitudinal direction of said belt, a pair of vertical support shafts for each of said carriages, a guide roller rotatably mounted on the end of each of said support shafts to engage a respective edge of said conveyor belt, tie rod means to couple said carriages together, said carriages having mounted thereon an excitor coil and a pair of receiver coils in aligned relationship to said loop coils, said receiving coils capable of receiving respective signals from said excitor coil through the loop coils, and a fissure detector signal connected to said receiver coils and responsive to said signals therefrom indicative of the occurrence of fissure in said conveyor belt.

Claim 18

A belt fissure detection apparatus comprising a plurality of pairs of first and second elongated loop coils embedded in a conveyor belt at various intervals over the entire length of said conveyor belt said first loop coil of each pair extended in the longitudinal direction of said conveyor belt and adjacent to and along one edge of said conveyor belt, said second coil of each pair extended in a direction transverse to the longitudinal length of said conveyor for substantially the entire width thereof one coil end of said second loop coils in close proximity to one end of said first loop coils.

Claim 19

A belt fissure detection apparatus comprising a plurality of pairs of first and second elongated loop coils embedded in a conveyor belt at various intervals over the entire length of said conveyor belt said first loop coil of each pair extended in the longitudinal direction of said conveyor belt and adjacent to and along one edge of said conveyor belt, said second coil of each pair extended in a direction transverse to the longitudinal length of said conveyor for substantially the entire width thereof one coil end of said second loop coils in close proximity to one end of said first loop coils.

Claim 20

The belt fissure detection apparatus of claim 12 characterized in that said one coil end of said first and second loop are in overlayed relation within said conveyor belt.

Claim 21

The belt fissure detection apparatus of claim 12 characterized in that said loop coils are of quadrangular configuration.

Claim 22

The belt fissure detection apparatus of claim 12 characterized by a fissure detector circuit comprising an excitor coil connected to a current source and a pair of receiver coils connected to a fissure detection circuit means, said excitor coil positioned relative to said conveyor belt to be in electromagnetic coupling to said one end of each of said pair of first and second loop coils as said conveyor belt is driven, each of said receiver coils positioned relative to said conveyor belt to be in electromagnetic coupling to the respective other ends of each of said pairs of first and second loop coils as said conveyor belt is driven, said circuit detection means responsive to signals received from said receiver coils from said excitor through said first and second loop coils indicative of the nonoccurrence of a fissure in said conveyor belt.

Claim 23

The belt fissure detection apparatus of claim 15 characterized by conveyor belt tracking means to support said excitor and receiver coils to compensate for lateral meandering of said conveyor belt while the latter is being driven to maintain said coils at all times in electromagnetic coupling relation with said loop coil ends.

Claim 24

The belt fissure detection apparatus of claim 15 characterized in that said fissure detection circuit means includes circuit gate means to receive receiver signals, a bistable flip-flop network set and reset by the respective output signals of said circuit gate means; said flip-flop network productive of an output signal when one of said receiver signals is not received at said circuit gate means, and comparator circuit Means connected to receive said flip-flop network output signal and operative of an annunciator when said output signal is greater than a predetermined value.