Latch detector stop motion system for circular knitting machines

Claim 2

A stop motion device for detecting closed needle latches of needles moving through a test station near a yard feed station in a circular knitting machine wherein the needles and their latches conductively communicate with electrical ground and the latches in the region of said test station move along a normal path when in open position and move along an abnormal path when in undesired closed position, comprising a normally ungrounded electrically conductive contact probe disposed adjacent said test station at a location along said abnormal path to conductively contact any closed latch and momentarily establish an electrical grounding path from the probe through the closed latch, a bistable flip-flop circuit having first and second input terminals, the first input terminal being connected to said probe to be momentarily connected directly to ground through the probe and closed latch when the probe contacts a closed latch, said flip-flop circuit having connection means including means connecting supply voltage to the first input terminal to set the flip-flop circuit upon application of supply voltage thereto to a ready first state wherein a normal first voltage state is provided at an output thereof and wherein the flip-flop is conditioned to respond to momentary connection of its first input terminal to ground to shift the flip-flop to a second state causing said output to instantaneously change to a second voltage state, and a relay control circuit including a relay for stopping the knitting machine and circuit connections to said flip-flop output responsive to occurrence of said second voltage state to activate the relay to stop the knitting machine.

Claim 3

A stop motion device for detecting closed needle latches as defined in claim 1, including a normally non-conducting lamp controlling transistor connected to an indicator lamp to regulate current flow therethrough and connected to a second output of said flip-flop circuit to energize said indicator lamp when said probe contacts a closed latch.

Claim 4

A stop motion device for detecting closed needle latches as defined in claim 1, including a DC supply voltage source, said flip-flop circuit having said second input terminal connected through a resistor to said supply voltage source and through a capacitor to ground, and said first input terminal being maintained at a predetermined positive DC voltage level when said probe is not in contact with an electrically grounding conductor to coact with the voltage condition on said second input terminal to maintain said flip-flop circuit in said first state.

Claim 5

A stop motion device for detecting closed needle latches as defined in claim 1, wherein said bistable flip-flop circuit comprises a pair of NAND gates each having a pair of inputs and an output, one input of a first one of said NAND gates forming said first input terminal and being connected to said probe and through a resistor to a supply voltage source and an input of a second one of said NAND gates forming said second input terminal and being connected through a resistor to said supply voltage source and through a capacitor to ground and the remaining inputs of said NAND gates being cross-connected to the output of the other NAND gates, and said output of said flip-flop being the output of the second of said NAND gates.

Claim 6

A stop motion device for detecting closed needle latches as defined in claim 3, wherein said bistable flip-flop circuit comprises a pair of NAND gates eacH having a pair of inputs and an output, one input of a first one of said NAND gates forming said first input terminal and being connected to said probe and through a resistor to said supply voltage source and an input of a second one of said NAND gates forming said second input terminal and being connected through said first mentioned resistor to said supply voltage source and through said capacitor to ground and the remaining inputs of said NAND gates being cross-connected to the output of the other NAND gates, and said output of said flip-flop being the output of the second of said NAND gates.

Claim 7

A stop motion device as defined in claim 1 including gate means having a plurality of inputs and an output, means connecting one of said inputs to the output of said flip-flop circuit and the other inputs of said gate means being adapted to be connected to the similar output of similar flip-flop circuits of additional like closed latch detectors, and said relay control circuit including a normally non-conducting relay driver transistor controlling current flow through the winding of said relay and connected to the input of said gate means to conduct and activate said relay upon application of said second voltage state to any of the inputs of said gate means.

Claim 8

A stop motion device as defined in claim 5 including gate means having a plurality of inputs and an output, means connecting one of said gate inputs to the output of said flip-flop circuit and the other inputs of said gate means being adapted to be connected to the similar output of similar flip-flop circuits of additional like closed latch detectors, and said relay control circuit including a normally non-conducting relay driver transistor controlling current flow through the winding of said relay and connected to the input of said gate means to conduct and activate said relay upon application of said second voltage state to any of the inputs of said gate means.

Claim 9

A stop motion device for detecting closed needle latches of needles moving through a test station near a yarn feed station in a circular knitting machine wherein the needles and their latches conductively communicate with electrical ground and the latches in the region of said test station move along a normal path when in open position and move along an abnormal path when in undesired closed position, comprising a normally ungrounded electrically conductive contact probe disposed adjacent said test station at a location along said abnormal path to conductively contact any closed latches and momentarily establish an electricaly grounding path from the probe through the closed latch, a bistable flip-flop circuit formed of a pair of cross-connected NAND gates each having a pair of inputs and an output, one input of a first one of said NAND gates forming a first input terminal for the flip-flop circuit connected to said probe to be momentarily connected directly to ground through the probe and closed latch when the probe contacts a closed latch, connecting means including connections between said NAND gates and including means connecting supply voltage to said first input terminal to initially set the flip-flop circuit to a ready first state wherein a normal first voltage state is provided at the output of said second NAND gate and wherein the flip-flop is conditioned to respond to momentary connection of said first input terminal to ground by probe engagement with a closed latch to shift the flip-flop to a second state causing said output of the second NAND gate to instantaneously change to a second voltage state, and a relay control circuit including a relay for stopping the knitting machine and circuit connections to the output of said second NAND gate responsive to occurrence of said second voltage state to activate the relay to stop the knitting machine.

Claim 10

A stop motion device for detecting closed needle latches of needles moving through a test station near a yarn feed station in a circular knitting machine wherein the needles and their latches conductively communicate with electrical ground and the latches in the region of said test station move along a normal path when in open position and move along an abnormal path when in undesired closed position, comprising a normally ungrounded electrically conductive contact probe disposed adjacent said test station at a location along said abnormal path to conductively contact any closed latches and momentarily establish an electricaly grounding path from the probe through the closed latch, a bistable flip-flop circuit formed of a pair of cross-connected NAND gates each having a pair of inputs and an output, one input of a first one of said NAND gates forming a first input terminal for the flip-flop circuit connected to said probe to be momentarily connected directly to ground through the probe and closed latch when the probe contacts a closed latch, connecting means including connections between said NAND gates and including means connecting supply voltage to said first input terminal to initially set the flip-flop circuit to a ready first state wherein a normal first voltage state is provided at the output of said second NAND gate and wherein the flip-flop is conditioned to respond to momentary connection of said first input terminal to ground by probe engagement with a closed latch to shift the flip-flop to a second state causing said output of the second NAND gate to instantaneously change to a second voltage state, and a relay control circuit including a relay for stopping the knitting machine and circuit connections to the output of said second NAND gate responsive to occurrence of said second voltage state to activate the relay to stop the knitting machine.

Claim 11

A stop motion device for detecting closed needle latches as defined in claim 8, wherein each of said NAND gates respond to predetermined low and higher input voltaGe levels to determine the output voltage states thereof, and said connecting means includes a resistor connected between said first input of said first NAND gate and said supply voltage to immediately apply a higher input voltage level to said first input upon initial application of supply voltage to the flip-flop circuit, and the connecting means further including means for momentarily applying a low input voltage level to the second input of the second NAND gate causing its output to apply a higher input voltage level to the first NAND gate to cause the flip-flop to be set and maintained in said ready first state until the probe is electrically grounded by engagement with a closed latch.

Claim 12

A stop motion device as defined in claim 8, including gate means having a plurality of inputs and an output, means connecting one of said inputs to the output of the second one of said NAND gates and the other inputs of said gate means being adapted to be connected to the similar output of similar flip-flop circuits of additional like closed latch detectors, and said relay control circuit including a normally nonconducting relay driver transistor controlling current flow through the winding of said relay and connected to the output of said gate means to conduct and activate said relay upon application of said higher voltage state to any of the inputs of said gate means.

Claim 13

A stop motion device as defined in claim 9, including gate means having a plurality of inputs and an output, means connecting one of said inputs to the output of the second one of said NAND gates and the other inputs of said gate means being adapted to be connected to the similar output of similar flip-flop circuits of additional like closed latch detectors, and said relay control circuit including a normally nonconducting relay driver transistor controlling current flow through the winding of said relay and connected to the output of said gate means to conduct and activate said relay upon application of said higher voltage state to any of the inputs of said gate means.

Claim 14

A stop motion device as defined in claim 10, including a normally non-conducting lamp controlling transistor connected to an indicator lamp to regulate current flow therethrough and connected to the output of the first one of said NAND gates to energize said indicator lamp when said probe contacts a closed latch.

Claim 15

A stop motion device for detecting closed needle latches moving through a test station near a yarn feed station in a circular knitting machine wherein the needles and their latches conductively communicate with electrical ground and the latches in the region of said test station move along a normal path when in open position and move along an abnormal path when in undesired closed position, comprising a normally ungrounded electrically conductive contact probe disposed adjacent said test station at a location along said abnormal path to conductively contact any closed latch and momentarily establish an electrical grounding path from the probe through the closed latch, a bistable flip-flop circuit comprising a pair of NAND gates each having a pair of inputs and an output, one input of the first one of said NAND gates being connected to said probe and through a resistor to a supply voltage source and an input of a second one of said NAND gates being connected through a resistor to the supply voltage source and through a capacitor to ground and the remaining inputs of said NAND gates being cross-connected to the output of the other NAND gate whereby the flip-flop circuit is automatically set to a first state upon application of supply voltage to the flip-flop circuit providing a normal first voltage state at the output of the second NAND gate which first state is maintained until the probe contacts a closed latch and the cross-connections of the NAND gates causing the flip-flop circuit to shift to a second state providing a second voltage state at the output of said second NAND gate upon momentarY grounding of the probe by contact with the closed latch, and a relay control circuit including a relay for stopping the knitting machine and circuit connections to the output of said second NAND gate responsive to occurrence of said second voltage state to activate the relay to stop the knitting machine.

Claim 16

A stop motion device for detecting closed needle latches moving through a test station near a yarn feed station in a circular knitting machine wherein the needles and their latches conductively communicate with electrical ground and the latches in the region of said test station move along a normal path when in open position and move along an abnormal path when in undesired closed position, comprising a normally ungrounded electrically conductive contact probe disposed adjacent said test station at a location along said abnormal path to conductively contact any closed latch and momentarily establish an electrical grounding path from the probe through the closed latch, a bistable flip-flop circuit comprising a pair of NAND gates each having a pair of inputs and an output, one input of the first one of said NAND gates being connected to said probe and through a resistor to a supply voltage source and an input of a second one of said NAND gates being connected through a resistor to the supply voltage source and through a capacitor to ground and the remaining inputs of said NAND gates being cross-connected to the output of the other NAND gate whereby the flip-flop circuit is automatically set to a first state upon application of supply voltage to the flip-flop circuit providing a normal first voltage state at the output of the second NAND gate which first state is maintained until the probe contacts a closed latch and the cross-connections of the NAND gates causing the flip-flop circuit to shift to a second state providing a second voltage state at the output of said second NAND gate upon momentarY grounding of the probe by contact with the closed latch, and a relay control circuit including a relay for stopping the knitting machine and circuit connections to the output of said second NAND gate responsive to occurrence of said second voltage state to activate the relay to stop the knitting machine.