Method of and apparatus for maintaining substantially constant a quantity of opened fibrous material

Claim 1

A method for maintaining substantially constant a quantity of opened fibrous material delivered per unit of time, to a spinning preparatory machine, comprising the steps of: (a) generating a conveying air stream by means of a fan having a characteristic diagram; (b) flowing the conveying air stream into a transporting duct for the fibrous material; (c) supplying the fibrous material into the transporting duct in such manner that the material is accelerated by the conveying air stream and a change in the quantity of material accelerated per unit time causes a corresponding change in the operating condition of the fan as represented by said characteristic diagram; (d) delivering the accelerated fibrous material within the duct in the direction of the spinning preparatory machine; (e) measuring a parameter which is characteristic for the operating condition of the fan; (f) comparing the measured parameter with a set value parameter corresponding to a desired operating condition of the fan and hence to a desired quantity of opened fibrous material which is to be delivered per unit of time to the spinning preparatory machine; (g) upon deviation of the measured parameter from the set value parameter, adjusting the further supply of fibrous material into the transporting duct until re-establishing a supply of fibrous material to said spinning preparatory machine corresponding to the substantially constant quantity of opened fibrous material desired to be delivered to the spinning preparatory machine; wherein the characteristic parameter which is measured is the drive moment of the fan.

Claim 2

A method for maintaining substantially constant a quantity of opened fibrous material delivered per unit of time, to a spinning preparatory machine, comprising the steps of: (a) generating a conveying air stream by means of a fan having a characteristic diagram; (b) flowing the conveying air stream into a transporting duct for the fibrous material; (c) supplying the fibrous material into the transporting duct in such manner that the material is accelerated by the conveying air stream and a change in the quantity of material accelerated per unit time causes a corresponding change in the operating condition of the fan as represented by said characteristic diagram; (d) delivering the accelerated fibrous material within the duct in the direction of the spinning preparatory machine; (e) measuring a parameter which is characteristic for the operating condition of the fan; (f) comparing the measured parameter with a set value parameter corresponding to a desired operating condition of the fan and hence to a desired quantity of opened fibrous material which is to be delivered per unit of time to the spinning preparatory machine; (g) upon deviation of the measured parameter from the set value parameter, adjusting the further supply of fibrous material into the transporting duct until re-establishing a supply of fibrous material to said spinning preparatory machine corresponding to the substantially constant quantity of opened fibrous material desired to be delivered to the spinning preparatory machine; wherein the characteristic parameter which is measured is the drive moment of the fan.

Claim 4

A method for maintaining substantially constant a quantity of opened fibrous material delivered per unit of time, to a spinning preparatory machine, comprising the steps of: (a) generating a conveying air stream by means of a fan having a characteristic diagram; (b) flowing the conveying air stream into a transporting duct for the fibrous material; (c) supplying the fibrous material into the transporting duct in such manner that the material is accelerated by the conveying air stream and a change in the quantity of material accelerated per unit time causes a corresponding change in the operating condition of the fan as represented by said characteristic diagram; (d) delivering the accelerated fibrous material within the duct in the direction of the spinning preparatory machine; (e) measuring a parameter which is characteristic for the operating condition of the fan; (f) comparing the measured parameter with a set value parameter corresponding to a desired operating condition of the fan and hence to a desired quantity of opened fibrous material which is to be delivered per unit of time to the spinning preparatory machine; (g) upon deviation of the measured parameter from the set value parameter, adjusting the further supply of fibrous material into the transporting duct until re-establishing a supply of fibrous material to said spinning preparatory machine corresponding to the substantially constant quantity of opened fibrous material desired to be delivered to the spinning preparatory machine; wherein the characteristic parameter which is measured is a value of the power drawn by the fan.

Claim 5

A method for maintaining substantially constant a quantity of opened fibrous material delivered per unit of time, to a spinning preparatory machine, comprising the steps of: (a) generating a conveying air stream by means of a fan having a characteristic diagram; (b) flowing the conveying air stream into a transporting duct for the fibrous material; (c) supplying the fibrous material into the transporting duct in such manner that the material is accelerated by the conveying air stream and a change in the quantity of material accelerated per unit time causes a corresponding change in the operating condition of the fan as represented by said characteristic diagram; (d) delivering the accelerated fibrous material within the duct in the direction of the spinning preparatory machine; (e) measuring a parameter which is characteristic for the operating condition of the fan; (f) comparing the measured parameter with a set value parameter corresponding to a desired operating condition of the fan and hence to a desired quantity of opened fibrous material which is to be delivered per unit of time to the spinning preparatory machine; (g) upon deviation of the measured parameter from the set value parameter, adjusting the further supply of fibrous material into the transporting duct until re-establishing a supply of fibrous material to said spinning preparatory machine corresponding to the substantially constant quantity of opened fibrous material desired to be delivered to the spinning preparatory machine; wherein the characteristic parameter which is measured is a value of the power drawn by the fan.

Claim 7

An apparatus for maintaining substantially constant a quantity of fibrous material which is in the process of being transported by an air stream and delivered per unit of time to a spinning preparatory machine, comprising: (a) a pneumatic transporting duct; (b) a fan having a characteristic diagram and operatively connected with the pneumatic transporting duct for generating an air stream moving through the pneumatic transporting duct; (c) a supply device for feeding fibrous material into the transporting air stream; (d) said transporting duct comprising an acceleration zone for the fibrous material, the one end of the acceleration zone being in communication with the fan so that a change in the quantity of material accelerated per unit time causes a corresponding change in the operating condition of the fan as represented by said characteristic diagram; (e) a measuring device arranged for measuring a parameter which is characteristic for the operating condition of the fan; (f) a control device operatively connected with the supply device and said measuring device; (g) the control device including means for producing a value by comparing the measured parameter with a set value parameter corresponding to a desired fan operating condition and hence to a desired quantity of opened fibrous material which is to be delivered per unit of time to the spinning preparatory machine and for adjusting the further supply of fibrous material into the transporting duct in dependence upon said value until re-establishing a supply of fibrous material to said spinning preparatory machine corresponding to the substantially constant quantity of opened fibrous material desired to be delivered to the spinning preparatory machine; and (h) said fan for generating the air stream possesses a drive shaft, said measuring device serving to measure a rotational moment of said fan and being arranged to the drive shaft thereof.

Claim 8

An apparatus for maintaining substantially constant a quantity of fibrous material which is in the process of being transported by an air stream and delivered per unit of time to a spinning preparatory machine, comprising: (a) a pneumatic transporting duct; (b) a fan having a characteristic diagram and operatively connected with the pneumatic transporting duct for generating an air stream moving through the pneumatic transporting duct; (c) a supply device for feeding fibrous material into the transporting air stream; (d) said transporting duct comprising an acceleration zone for the fibrous material, the one end of the acceleration zone being in communication with the fan so that a change in the quantity of material accelerated per unit time causes a corresponding change in the operating condition of the fan as represented by said characteristic diagram; (e) a measuring device arranged for measuring a parameter which is characteristic for the operating condition of the fan; (f) a control device operatively connected with the supply device and said measuring device; (g) the control device including means for producing a value by comparing the measured parameter with a set value parameter corresponding to a desired fan operating condition and hence to a desired quantity of opened fibrous material which is to be delivered per unit of time to the spinning preparatory machine and for adjusting the further supply of fibrous material into the transporting duct in dependence upon said value until re-establishing a supply of fibrous material to said spinning preparatory machine corresponding to the substantially constant quantity of opened fibrous material desired to be delivered to the spinning preparatory machine; and (h) said fan for generating the air stream possesses a drive shaft, said measuring device serving to measure a rotational moment of said fan and being arranged to the drive shaft thereof.

Claim 9

An apparatus for maintaining substantially constant a quantity of fibrous material which is in the process of being transported by an air stream and delivered per unit of time to a spinning preparatory machine, comprising: (a) a pneumatic transporting duct; (b) a fan having a characteristic diagram and operatively connected with the pneumatic transporting duct for generating an air stream moving through the pneumatic transporting duct; (c) a supply device for feeding fibrous material into the transporting air stream; (d) said transporting duct comprising an acceleration zone for the fibrous material, the one end of the acceleration zone being in communication with the fan so that a change in the quantity of material accelerated per unit time causes a corresponding change in the operating condition of the fan as represented by said characteristic diagram; (e) a measuring device arranged for measuring a parameter which is characteristic for the operating condition of the fan; (f) a control device operatively connected with the supply device and said measuring device; (g) the control device including means for producing a value by comparing the measured parameter with a set value parameter corresponding to a desired fan operating condition and hence to a desired quantity of opened fibrous material which is to be delivered per unit of time to the spinning preparatory machine and for adjusting the further supply of fibrous material into the transporting duct in dependence upon said value until re-establishing a supply of fibrous material to said spinning preparatory machine corresponding to the substantially constant quantity of opened fibrous material desired to be delivered to the spinning preparatory machine; and (h) an electric motor for driving said fan, an electrical supply circuit for said electric motor, said measuring device serving to measure an electrical power take-up of the electric motor driving the fan and being arranged in the electrical supply circuit of the electric motor.

Claim 10

An apparatus for maintaining substantially constant a quantity of fibrous material which is in the process of being transported by an air stream and delivered per unit of time to a spinning preparatory machine, comprising: (a) a pneumatic transporting duct; (b) a fan having a characteristic diagram and operatively connected with the pneumatic transporting duct for generating an air stream moving through the pneumatic transporting duct; (c) a supply device for feeding fibrous material into the transporting air stream; (d) said transporting duct comprising an acceleration zone for the fibrous material, the one end of the acceleration zone being in communication with the fan so that a change in the quantity of material accelerated per unit time causes a corresponding change in the operating condition of the fan as represented by said characteristic diagram; (e) a measuring device arranged for measuring a parameter which is characteristic for the operating condition of the fan; (f) a control device operatively connected with the supply device and said measuring device; (g) the control device including means for producing a value by comparing the measured parameter with a set value parameter corresponding to a desired fan operating condition and hence to a desired quantity of opened fibrous material which is to be delivered per unit of time to the spinning preparatory machine and for adjusting the further supply of fibrous material into the transporting duct in dependence upon said value until re-establishing a supply of fibrous material to said spinning preparatory machine corresponding to the substantially constant quantity of opened fibrous material desired to be delivered to the spinning preparatory machine; and (h) an electric motor for driving said fan, an electrical supply circuit for said electric motor, said measuring device serving to measure an electrical power take-up of the electric motor driving the fan and being arranged in the electrical supply circuit of the electric motor.

Claim 11

An apparatus for maintaining substantially constant a quantity of fibrous material which is in the process of being transported by an air stream and delivered per unit of time to a spinning preparatory machine, comprising: (a) a pneumatic transporting duct; (b) a fan having a characteristic diagram and operatively connected with the pneumatic transporting duct for generating an air stream moving through the pneumatic transporting duct; (c) a supply device for feeding fibrous material into the transporting air stream; (d) said transporting duct comprising an acceleration zone for the fibrous material, the one end of the acceleration zone being in communication with the fan so that a change in the quantity of material accelerated per unit time causes a corresponding change in the operating condition of the fan as represented by said characteristic diagram; (e) a measuring device arranged for measuring a parameter which is characteristic for the operating condition of the fan; (f) a control device operatively connected with the supply device and said measuring device; (g) the control device including means for producing a value by comparing the measured parameter with a set value parameter corresponding to a desired fan operating condition and hence to a desired quantity of opened fibrous material which is to be delivered per unit of time to the spinning preparatory machine and for adjusting the further supply of fibrous material into the transporting duct in dependence upon said value until re-establishing a supply of fibrous material to said spinning preparatory machine corresponding to the substantially constant quantity of opened fibrous material desired to be delivered to the spinning preparatory machine; wherein said transporting duct comprises an acceleration tube having a first end operatively connected with the fan generating the air stream and a free end opening into a region at which there prevails a substantially constant pressure; wherein said transporting duct comprises said acceleration tube and a tubular duct, said tubular duct having a free end, the free end of said acceleration tube being arranged in confronting spaced relationship from said free end of said tubular duct.

Claim 12

An apparatus for maintaining substantially constant a quantity of fibrous material which is in the process of being transported by an air stream and delivered per unit of time to a spinning preparatory machine, comprising: (a) a pneumatic transporting duct; (b) a fan having a characteristic diagram and operatively connected with the pneumatic transporting duct for generating an air stream moving through the pneumatic transporting duct; (c) a supply device for feeding fibrous material into the transporting air stream; (d) said transporting duct comprising an acceleration zone for the fibrous material, the one end of the acceleration zone being in communication with the fan so that a change in the quantity of material accelerated per unit time causes a corresponding change in the operating condition of the fan as represented by said characteristic diagram; (e) a measuring device arranged for measuring a parameter which is characteristic for the operating condition of the fan; (f) a control device operatively connected with the supply device and said measuring device; (g) the control device including means for producing a value by comparing the measured parameter with a set value parameter corresponding to a desired fan operating condition and hence to a desired quantity of opened fibrous material which is to be delivered per unit of time to the spinning preparatory machine and for adjusting the further supply of fibrous material into the transporting duct in dependence upon said value until re-establishing a supply of fibrous material to said spinning preparatory machine corresponding to the substantially constant quantity of opened fibrous material desired to be delivered to the spinning preparatory machine; wherein said transporting duct comprises an acceleration tube having a first end operatively connected with the fan generating the air stream and a free end opening into a region at which there prevails a substantially constant pressure; wherein said transporting duct comprises said acceleration tube and a tubular duct, said tubular duct having a free end, the free end of said acceleration tube being arranged in confronting spaced relationship from said free end of said tubular duct.