US2124415A - Driving means for spinning machines - Google Patents

Description

July 19, 1938. E. A. GREEN DRIVING MEANS FOR SPINNING MACHINES Fi-led June 16, 1957 Inventor: Edward A.Gr-een y d/za/. His Attorney.

Patented July 19, 1938 I UNlTED STATES PATENT OFFICE Edward A. Green, Schenectady, N. Y., assignor to General Electric Company, a corporation of New York Application June 16, 1937, Serial No. 148,487

7 Claims.

My invention relates to driving means for spinning machines and the like, more particularly to driving means in which each spindle is driven by a separate motor, and has for its 5 object a simple and reliable system for starting and stopping the spindle motors in synchronism with each other and in a predetermined proportionate speed relation with drivin means for the other parts of the spinning ma- 10 chine.

In the operation of spinning machines wherein the spindles are driven by separate high-speed motors and wherein the feeding means and other mechanism, such as the ring rail, are driven 15 by a low-speed motor in the conventional manner it has been found that when the spindle motors and the feed driving motor are de-energized to stop the machine, the motors do not decelerate in synchronism, i. e., in adesired time relation or at the same proportionate rate. The spindle motors tend to coast for a longer period of time with the result that the yarn is twisted excessively between the bobbin and feed rolls.

. This is detrimental to the yarn and results in 25 a length of yarn of inferior quality on the bobbin when the machine is shut down when the bobbins are only partly filled. Moreover, the excessively twisted portion often results in breakage of the yarn when the machine is started.

30 In accordance with my invention I provide a main low-speed low-frequency driving motor which is large enough to drive the complete machine, but which is mechanically connected to drive directly only those parts ofthe machine 35 other than the spindles such as the feeding means and the ring rail. For energization of the separate high-speed spindle motors I provide a high frequency generator which is driven from the main driving motor, together with suitable switching means for energizing the field of the generator when the main driving motor is energized, for maintaining the excitation of the generator during the decelerating period, and increasing it at the beginning of the acceleration and the completion of the deceleration. Thus the spindle motors are electrically locked with the generator during acceleration and de-' celeration and during deceleration may be re- 50 generatively braked through the generator in the event that they do not decelerate as fast as the main driving motor.

For a more complete understanding of my invention reference should be had to the accom- 55 panying drawing the single figure of which isa able direct current source of supply 28.

diagrammatic representation of a driving system for spinning machines embodying my invention.

Referring to the drawing, for purposes of simplicity and clarity the elements of the spinning machine essential to an understanding of the 5 invention only have been shown. It will be understood that my invention is applicable to any spinning machine and the like with separate driving motors for the spindles, including machines in which there is no draft mechanism, sometimes known as twisting machines. The spinning machine comprises suitable feed and draft mechanism ill for feeding the untwisted yarn from the bobbin Ii to the bobbin M on the spindle l3, a suitable ring rail mechanism It being provided for simultaneously effecting the twisting and feeding of the yarn to the bobbin in a conventional manner. It will be understood that the machine consists of a plurality of feeding bobbins ii, and spinning bobbins i2, perhaps several hundred, with suitable feeding mechanism. Each bobbin i2 is driven by a separate individual high-frequency high-speed motor I! having a speed on the order of 6,000 to 12,000 R. P. M. so that the motor can be connected directly to its spindle.

In accordance with my invention I provide a main driving motor l6 of sufliclent size to drive the entire machine including the spindles II. This motor, however, is connected to drive directly through gearing I1 and shaft IS the feed and various other mechanism of the machine but not the spindles I3. For the operation of the spindles I provide a generator I9, having a normal high frequency, such as 180 cycles, which is connected through suitable gearing 20 to the main driving motor It. The spindle motors I! are connected in parallel relation to each other to the high frequency generator IS. The speed of the generator I9 and hence its frequency and the speed of the spindle motors it: may be varied by suitably varying the ratio of the gearing 20.

The main driving motor i6 is preferably a suitable three-phase motor of standard frequency such as a three-phase 60 cycle squirrel cage induction motor. It may be connected by means of an electromagnetic switch 2| to a suitable three-phase supply source 22, the coil 23 of the switch being controlled by suitablemeans such as push buttons 2! and 25.

For the control of the field of the generator it I have provided an electromagnetic switch "for connecting the field circuit 21 to a suit- The coil 2! of this switch is controlled by a contact and closed simultaneously with the switch 2|.

Therefore, when the switch 28 is closed by closing the button 24, which is preferably provided with suitable means for holding it closed, the switch 28 is closed and field energization applied to the generator whereby the voltage oi the generator gradually buildsup as the speed of the generator increases with the speed of the motor 96. Consequently the spindle motors is are accelerated in a predetermined proportionate speed relation with the main driving motor 6%.

Preferably the spindle motors it are three-phase high-torque squirrel cage induction motors which accelerate in synchronism with the increase in frequency of the generator.

When it is desired to stop the machine the button 25 is depressed to de-energize the coil 23, the button 2 3 being thereupon opened. Preferably a suitable time delay mechanism such as a dashpot Si is provided for the switch 26 so that it is held closed, after the de-energization of its coil it, during the decelerating period. 0r suitable timing mechanism maybe provided for delaying the de-energization of the coil 29 for a predetermined interval after the opening of the contact 863. Thus during deceleration the spindle motors it are electrically locked to the generator is which in turn is mechanically locked to the driving motor 96. This assures deceleration of the motors together, In case the spindle motors tend to decelerate at a proportionately slower rate than the driving motor they act as generators supplying power to the generator it which then acts as a motor and tends to drive or prevent deceleration of the motor it.

To further assure the electrical interlocking of the spindle motors with the generator W at low speeds and low frequencies during both the acceleration and deceleration, I have provided a centrifugal speed-responsive device 82 which is driven by the motor 96 and operates a pivoted switch arm 83. At low speeds this switch arm as shown in thedrawing closes a circuit around a resistance 34, in the field circuit of the generator 89. This provides for increased excitation of the generator at low speeds. At a predetermined high speed the centrifugal device moves the arm 33 to open the circuit around the resistance 36 thereby inserting the remittance in the field circuit and decreasing the field to its normal value.

In accordance with the provisions of the patent statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to represent thebest embodiment thereof, but I desire to have it understood that the apparatus shown is only illustrative and that the invention may be carried out by other means.

What I claim as new and desire to secure by Letters Patent oi the United States is:.

l. A driving system for spinning machines and the like provided with yarn feeding means and. individual spindle motors, comprising a main driving motor for said feeding means, a generator provided with a field circuit and connected to be driven by said main driving motor, electrical connections between said generator and said spindle motors, main switching means for controlling the energization of said maindriving motor, and field switching means in said field circuit controlled by said main switching means to energize the field of said generator whereby said spindle motors are started and accelerated with said main drivi motor. .r

2. A driving system for spinning machines and the like provided with yarn feeding means and individual high-speed spindle motors, comprising a main driving motor for said feeding means, a high-frequency generator provided with a field circuit and connected to be driven by said main driving motor, electrical connections between said generator and said feed motors, main switching means for controlling the energization of said main driving motor, field switching means in said field circuit operated by said main switching means to energize the field of said generator simultaneously with the energization of said main driving motor whereby said spindle motors are started simultaneously with said main driving motor, and means responsive to the speed of said generator for increasing the field excitation of said generator during low speed operation of said generator.

3. A driving system for spinning machines and the like provided with yarn feeding means and individual spindle motors, comprising a main driving motor for said feeding means, a generator provided with a field circuit and connected to be driven by said main driving motor, electrical connections between said generator and said spindle motors, switching means for energizing-said main driving motor and said field circuit whereby said spindle motors are started with said main driving motor, and means for maintaining the field circuit of said generator energized after deenergization of said main driving motor until said main motor and said spindle motors have come to rest.

4. A driving system for spinning machines and the like provided with yarn feeding means and individual spindle motors, comprising a main driving motor for said feeding means, a generator provided with a field circuit and connected to be driven by said main driving motor, electrical connections between said generator and said spindle motors, main switching means for controlling the energization of said main driving motor, field switching means in said field circuit controlled by said main switching means to energize the field of said generator whereby said spindle motors are started and accelerated with said main driving motor, and means for maintaining the field circuit of said generator closed after operation of said main switching means to deenergize said main driving motor until said main motor and said spindle motors have come to rest, whereby said spindle motors and said main motor are decelerated in a predetermined proportionate speed relation with each other.

5. A driving system for spinning machines and the like provided with yarn feeding means and individual high-speed spindle motors, comprising a main driving motor for said feeding means, a high-frequency generator provided with a field circuit and connected to be driven by said main driving motor, electrical connections between said generator and said feed motors, main switching means for controlling the energization of said main driving motor, field switching means in said field circuit operated by said main switching means to energize the field of said generator simultaneously with the energization of said main driving motor whereby said spindle motors are started simultaneously with said main driving motor, means controlling said field switching means to maintain the field circuit of said gen crater energized after deenergization of said main driving motor until said main motor and said spindle motors have come to rest, whereby said spindle motors and said main motor are decelerated in a predetermined proportionate speed relation with each other, and means responsive to the speed of said generator for increasing the field excitation of said generator during low speed operation.

6. A driving system for spinning machines and the like provided with yarn feeding means and individual highspeed spindle motors, comprising a main driving motor connected to drive said feeding means, a high-frequency generator provided with a field circuit and connected to be driven by said main driving motor, electrical connections between said generator and said spindle motors, main switching means for controlling-the energization of said main driving motor, field switching means in said field circuit operated to closed'position by said main switching means to energize the field of said generator simultaneously with the closure of said main switching means to energize said main driving motor whereby said spindle motors are started and accelerated in a predetermined proportionate speed relation with said main driving motor, and means for maintaining said field switching means closed for a predetermined time interval after the opening of said main switching means for deenergization of said main driving motor thereby to maintain field energization of said generator until said main motor and said spindle motors have come to rest, whereby said spindle motors and said main motor are decelerated in a predetermined proportionate speed relation with each other.

'7. A driving system for spinning machines and the like provided with yarn feeding means and with the closure of said main switching means to energize said main driving motor whereby said spindle motors are started and accelerated in a predetermined proportionate speed relation with said main driving motor, means for maintaining said field switching means closed for a predetermined time interval after the opening of said main switching means for deenergization of said main driving motor thereby to maintain field energization of said generator until said main motor and said spindle motors have come to rest, whereby said spindle motors and said main motor are decelerated in a predetermined proportionate speed relation with each other, and means responsive to the speed of said generator for increasing the excitation of said generator during low-speed operation of said generator.

EDWARD A. GREEN.

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