Yarn tension control device

Claim 2

Yarn tension control means for controlling the tension in yarn travelling from a source of supply to a work station on a knitting machine comprising: a. yarn sensing means adapted to be operatively engaged by said travelling yarn; b. said yarn sensing means being movable from a normal operating position thereof in response to increased yarn tension to another position thereof in which it is operative to cause the activation of a stop motion for interrupting the knitting machine drive; c. an electrically operated means operatively connected to said yarn sensing means for supplying thereto a preselected force for selectively controlling the net force opposing the movement of said yarn sensing means in response to increased yarn tension, whereby to selectively adjust the tension in said yarn, beyond which stop motion is activated; d. said yarn sensing means being attached to support means therefor adapted to move downwardly in unison with said yarn sensing means, in response to said increased yarn tension; e. said support means comprising a tape, wound onto a reel therefor, the end of said tape having said yarn sensing means attached thereto.

Claim 3

Yarn tension control means in accordance with claim 1, wherein said electrically operated means comprises an electric motor operatively connected to said reel, and motor control circuitry for selectively adjusting the direction and magnitude of rotational force applied to said reel for correspondingly selectively adjusting the direction and magnitude of lineal force applied to the free end of said tape and to said yarn sensing means.

Claim 4

Yarn tension control means in accordance with claim 2, wherein there is provided a contact member adapted to be normally supported by the travelling yarn portion which is in engagement with the yarn sensing means when the latter is in said normal operating position thereof, said contact member being automatically movable to a stop motion circuit completing position thereof when said yarn sensing means is moved to said another position thereof in response to an increase in yarn tension which overcomes the opposing force selectively applied to said yarn sensing means by said electric motor.

Claim 5

Yarn tension control means in accordance with claim 2, wherein said motor control circuitry comprises: a. a relay; b. a pair of switches movable under control of said relay from a first position providing for current flow through said motor in one direction to a second position providing for current flow through said motor in the opposite direction; c. a first pushbutton operative, when depressed, to energize said relay for placing said pair of switches in said first position for providing current flow through said motor in said one direction; d. a second pushbutton operative, when depressed, to prevent energization of said relay for placing said pair of switches in said second position for providing current flow through said motor in said opposite direction; and e. switch means operable, when said pushbuttons are undepressed, to selectively energize and deenergize said relay and to simultaneously place in circuit with said motor adjustable resistor means, for selectively controlling the amount of current flow through said motor.

Claim 6

Yarn tension control means for controlling the tension in yarn travelling from a source of supply to a work stAtion on a knitting machine comprising: a. yarn sensing means adapted to be operatively engaged by said travelling yarn; b. said yarn sensing means being movable from a normal operating position thereof in response to increased yarn tension to another position thereof in which it is operative to cause the activation of a stop motion for interrupting the knitting machine drive; c. electrically operated means operatively connected to said yarn sensing means for applying thereto a preselected force for selectively controlling the net force opposing the movement of said yarn sensing means in response to increased yarn tension, whereby to selectively adjust the tension in said yarn, beyond which said stop motion is activated; d. and a contact member adapted to be normally supported by the travelling yarn portion which is in engagement with the yarn sensing means when the latter is in said normal operating position thereof, said contact member being automatically movable to a stop motion circuit completing position thereof when said yarn sensing means is moved to said another position thereof in response to increased yarn tension.

Claim 7

Yarn tension control means for controlling the tension in yarn travelling from a source of supply to a work stAtion on a knitting machine comprising: a. yarn sensing means adapted to be operatively engaged by said travelling yarn; b. said yarn sensing means being movable from a normal operating position thereof in response to increased yarn tension to another position thereof in which it is operative to cause the activation of a stop motion for interrupting the knitting machine drive; c. electrically operated means operatively connected to said yarn sensing means for applying thereto a preselected force for selectively controlling the net force opposing the movement of said yarn sensing means in response to increased yarn tension, whereby to selectively adjust the tension in said yarn, beyond which said stop motion is activated; d. and a contact member adapted to be normally supported by the travelling yarn portion which is in engagement with the yarn sensing means when the latter is in said normal operating position thereof, said contact member being automatically movable to a stop motion circuit completing position thereof when said yarn sensing means is moved to said another position thereof in response to increased yarn tension.

Claim 8

Yarn tension control means in accordance with claim 5, wherein said yarn sensing means comprises a pair of spaced loops through which the travelling yarn is passed and wherein said contact member includes a tongue normally supported by the portion of the travelling yarn between said loops.

Claim 9

Yarn tension control means in accordance with claim 6, wherein said contact member includes an electrical contact element automatically biased into stop motion circuit completing position when said tongue ceases being supported by said travelling yarn portion.

Claim 10

Yarn tension control means for controlling the tension in yarn travelling from a source of supply to a work station on a knitting machine comprising: a. a housing; b. a reel mounted in said housing; c. a tape wound on said reel and having a free end extending outwardly of said housing; d. yarn sensing means attached to the free end of said tape and adapted to be operatively engaged by said travelling yarn, said yarn sensing means being movable from a normal operating position thereof in response to increased yarn tension of said travelling yarn; e. normally unenergized electrical circuit means in said housing adapted, when energized, to activate a stop motion for said knitting machine; f. a contact member adapted to be supported by the travelling yarn portion in engagement with said yarn sensing means when the latter is in said normal operating position thereof, said contact member being movable, when unsupported by said travelling yarn portion, to a position in which it causes the energization of said electrical circuit means; and g. means for selectively controlling the net force opposing the movement of said yarn sensing means in response to increased yarn tension, whereby to selectively adjust the tension in said yarn beyond which said stop motion is activated.

Claim 11

Yarn tension control means for controlling the tension in yarn travelling from a source of supply to a work station on a knitting machine comprising: a. a housing; b. a reel mounted in said housing; c. a tape wound on said reel and having a free end extending outwardly of said housing; d. yarn sensing means attached to the free end of said tape and adapted to be operatively engaged by said travelling yarn, said yarn sensing means being movable from a normal operating position thereof in response to increased yarn tension of said travelling yarn; e. normally unenergized electrical circuit means in said housing adapted, when energized, to activate a stop motion for said knitting machine; f. a contact member adapted to be supported by the travelling yarn portion in engagement with said yarn sensing means when the latter is in said normal operating position thereof, said contact member being movable, when unsupported by said travelling yarn portion, to a position in which it causes the energization of said electrical circuit means; and g. means for selectively controlling the net force opposing the movement of said yarn sensing means in response to increased yarn tension, whereby to selectively adjust the tension in said yarn beyond which said stop motion is activated.

Claim 12

Yarn tension control means in accordance with claim 8, wherein said means for selectively controlling said net opposing force comprises an electric motor operatively connected to said reel. 16 Yarn tension control means in accordance with claim 11, wherein there is provided motor control circuitry for selectively adjusting the direction and magnitude of rotational force applied to said reel for correspondingly selectively adjusting the direction and magnitude of linear force applied to the free end of said tape and to said yarn sensing means.

Claim 13

Yarn tension control means in accordance with claim 10, wherein said motor control circuitry includes means for rotating said reel in one direction, means for rotating said reel in opposite direction, and means for selectively adjusting the magnitude of rotational force applied to said reel.

Claim 14

Yarn tension control means in accordance with claim 8, wherein said yarn sensing means comprises a pair of spaced loops through whIch the travelling yarn is passed and wherein said contact member includes a tongue normally supported by the portion of the travelling yarn between said loops.

Claim 15

Yarn tension control means in accordance with claim 12, wherein said contact member includes an electrical contact element automatically biased into engagement with a contact finger in said housing thereby energizing said electrical circuit means.

Claim 16

Yarn tension control means in accordance with claim 13, wherein said means for selectively controlling said net opposing force comprises an electric motor operatively connected to said reel.

Claim 17

Yarn tension control means in accordance with claim 14, wherein there is provided motor control circuitry for selectively adjusting the direction and magnitude of rotational force applied to said reel for correspondingly selectively adjusting the direction and magnitude of linear force applied to the free end of said tape and to said yarn sensing means.

Claim 18

Yarn tension control means in accordance with claim 13, wherein guide means are provided for guiding said yarn sensing means during the movement thereof.

Claim 19

Yarn tension control means in accordance with claim 15, wherein said motor control circuitry comprises: a. a relay; b. a pair of switches movable under control of said relay from a first position providing for current flow through said motor in one direction to a second position providing for current flow through said motor in the opposite direction; c. a first pushbutton operative, when depressed, to energize said relay for placing said pair of switches in said first position for providing current flow through said motor in said one direction; d. a second pushbutton operative, when depressed, to prevent energization of said relay for placing said pair of switches in said second position for providing current flow through said motor in said opposite direction; and e. switch means operable, when said pushbuttons are undepressed, to selectively energize and deenergize said relay and to simultaneously place in circuit with said motor adjustable resistor means, for selectively controlling the amount of current flow through said motor.

Claim 20

Yarn tension control means for controlling the tension in yarn travelling from a source of supply to a work station on a knitting machine comprising: a. yarn sensing means adapted to be operatively engaged by said travelling yarn; b. said yarn sensing means being movable from a normal operating position thereof in response to increased yarn tension to another position thereof in which it is operative to cause the activation of a stop motion for interrupting the knitting machine drive; c. electrically operated means operatively connected to said yarn sensing means for applying thereto a preselected force for selectively controlling the net force opposing the movement of said yarn sensing means in response to increased yarn tension, whereby to selectively adjust the tension in said yarn, beyond which said stop motion is activated; and d. a contact member adapted to be normally supported by the travelling yarn portion which is in engagement with the yarn sensing means when the latter is in said normal operating position thereof, whereby a break in said yarn removes the normal support for said contact member, said contact member being automatically movable, in the absence of said normal support, to a stop motion circuit completing position thereof.

Claim 21

Yarn tension control means for controlling the tension in yarn travelling from a source of supply to a work station on a knitting machine comprising: a. yarn sensing means adapted to be operatively engaged by said travelling yarn; b. said yarn sensing means being movable from a normal operating position thereof in response to increased yarn tension to another position thereof in which it is operative to cause the activation of a stop motion for interrupting the knitting machine drive; c. electrically operated means operatively connected to said yarn sensing means for applying thereto a preselected force for selectively controlling the net force opposing the movement of said yarn sensing means in response to increased yarn tension, whereby to selectively adjust the tension in said yarn, beyond which said stop motion is activated; and d. a contact member adapted to be normally supported by the travelling yarn portion which is in engagement with the yarn sensing means when the latter is in said normal operating position thereof, whereby a break in said yarn removes the normal support for said contact member, said contact member being automatically movable, in the absence of said normal support, to a stop motion circuit completing position thereof.