US2250886A

US2250886A - Wire-drawing machine

Info

Publication number: US2250886A
Application number: US308223A
Authority: US
Inventors: Albert G Blodgett
Original assignee: Morgan Construction Co
Current assignee: Siemens Industry Inc
Priority date: 1939-12-08
Filing date: 1939-12-08
Publication date: 1941-07-29
Anticipated expiration: 1958-07-29

Description

A.A G. BLODGETT WIM-DRAWING MACHINE July 29, `1.941.

` Filed Dec. s', i959y Z af Patented July 29, 1941 WIRE-DRAWING MACHINE Albert G. Blodgett, Worcester, Mass., assigner to Morgan Construction Company, Mass., a corporation of Massachusetts Worcester,

Application December 8, 1939, Serial No. 308,223

3 claims.' (ci. 205-14) This invention relates to wire-drawing machines, and more particularly to machines of the type having a series of dies through which the wire is drawn by means of rotating drums or blocks to eifect successive reductions of the wire.

It has been recognized heretofore that certain advantages arise from the maintenance of an appreciable tension in the wire -between each drum and the V.succeeding die. This so-called bac tension not only decreases the power required to drive the machine, but it also prolongs the life of the dies by reducing the die friction and the resultant heat, and makes it pos-4 sible to draw wire at higher speeds. While atdrum I0 draws the Wire through the rst die I4, the wire then passing through the die lI5 to the drum II and thence through the die I6 to the drum I2, which serves as a nishing drum. The drum Ii) is driven by a motor I 8 which is connected to the drum by means of suitable gearing I9. Similarly, the drumII is drivenby a motor through the medium of gearing 2|.

The nishing drum I2 is driven by a motor 23 which is connected to the drum by means of gearing 24. The rate at which the wire passes through the machine is determined by the speed of the nishing drum I2, which in turn is detery mined-by the speed of the motor V23. This motempts have been made to constructmachines which would operate in this'manner, the prior machines have ingeneral been complicated, expensive, unreliable, and diiilcult to maintain in proper adjustment. l

It is accordingly one object of the invention to provide a simple, inexpensive and reliable wiredrawing machine of the type having rotatable drums to draw wire through a series of dies sucp applying a predetermined and readily adjustable torque to each of the drums.

It is a further object of lthe invention to provide a novel construction for a multiple die wiredrawing machine which is so arranged that the wire will neither slip on the drums nor continuously accumulate thereon during the operation of the machine.

With these` and other objects in view, as will be apparent to those skilled in the artfthe in'- vention resides in the combination of parts set forth in the specication and covered by the claims appended hereto.

Referring to the drawing illustrating one embodiment of the invention ,and in which like reference numerals indicate like parts,

Fig. 1 is'a somewhat diagrammatic view of a i wire-drawing machine; and

- Fig. 2 is an enlarged section taken on the line' j 2-,2 of Fig. 1. i

ltank 34.

tor may be an electric motor, and l't is preferablyv of the adjustable speed type so that the rate of wire drawing may be controlled.

The motors I8 and 20 are hydraulic motors of the constant displacement type. One suitable and well-known construction therefor is shown in Fig. 2 and comprises a pair of intermeshing gearsf26-26 which are forced to rotate by the pressure of the hydraulic iluid passing through 4the motor. A suitable fluid, such as oil, is supplied for the operation of the motors I8 and 20 through

pipes

21 and 28 respectively from a preure-producing source.. such as a lpump v3|) driven by an electric motor 3i. This pump may be of any suitable and well-known construction, and it may be supplied with oil through an inlet pipe 32 which communicates with a reservoir or Pipes 35 serve to return the exhaust fluid from the motors -to the reservoir. Means is preferably provided to control the pressure of the oil delivered by the pump, and for this pure' pose a by-pass 31 and'relief valve 38 are provided between the pump outlet and the exhaust. One suitable construction for the relief valve 38 is disclosed in the patent to Terry, No. 1,863,035.

Means is provided'to regulate automatically the pressure of the oil supplied'to the respective motors I8 and 20, thereby controlling the torque which these motors will apply t0 the wire-drawing drums. For this purpose a pressure reducing and regulating valve 40 is arranged to control the ow through the pipe 21,v and a similar valve 4I is arranged to control the flow through the pipe 28. Each of the valves 40 and 4I is provided with a handwheel 42 for the purpose of adjust' ment. These valves may be of any well-known type adapted to maintain a substantiallyconstant predetermined delivery pressure, one suitable construction being disclosed in the patent to Temple. No. Re. 19,545. For convenience in adjustment,l pressure gauges 43 are connected to the

pipes

21 and 28 to indicate the fluid pressure at the inlets of the respective hydraulic motors I8 and 20.

It will now be understood that with the apparatus as so far described each of the motors I8 and 20 will be supplied with operating fluid at a substantially constant pressure, which may be predetermined by the adjustment of the handwheels 42. Consequently the torque applied to the respective drums IIJ and II will be predetermined and substantially constant, since the motors are of the constant displacement type. By proper selection of the applied torque it is possible to maintain a predetermined back tension in the wire immediately anterior to the dies I and I5. The speeds of the drums I0 and will be determined by the speed of the nishing drum y 30. Consequently the unloaded drum will opera-te at high speed, and the remaining hydraulically driven drum or drums will not operate at all.

In order to overcome this difilculty Iprovide means whereby the flow of pressure fluid through each hydraulic motor is prevented unless the corresponding block is maintaining a tension in the wire anterior thereto. For this purpose, as shown in Fig. 1, a valve is provided in the pipe 21, this valve being operated by a solenoid 46, the construction being such that the valve will open when the solenoid is `energized andv A similar construction is provided in connection with the second die I5 and the second block II, the pipe 28 having a valve 51 therein which is 'operated by a solenoid 58 so arranged that the v'alve will open when the solenoid is energized and close when the solenoid is de-energized. The solenoid 58 is connected to a source 59 of electricity through a switch 5| which is biased toward open position by a spring 52 and shunted by a normally-open push button 53. The die I5 is slidable on a support 65 and connected to the switch 6| by means of a lever 66 fulcrummed The operation of the invention will now be apparent from the above disclosure. With the motor 3| running and no wire passing through the machine, the switches 49 and 5| will be held open by their

respective springs

50 and 62, the solenoids 45 and 58 will be de-energized, and the valves 45 and 51 will be closed. Hence no fluid will flow through the motors I8 and 29, and the blocks I0 and II will be stationary. To thread the machine, the operator will point the end of the wire, pass itthrough the rst die I4 and attach it by a suitable g'rip to the drum I0 in a well-known manner. He will then close the push button 5|, which will energize the solenoid 46 and 'open the valve 45, admitting fluid to the motor I8. This will rotate the drinn I0, and draw the wire through the die I4, which will slide'along its support 53 until the switch 49 is closed, so that the operator may release the push button without de-energizing the solenoid. When a suiiicient number of wraps of wire have been formed about the drum III, the operator will stop the machine yby stopping the electric motor 3|. H e will then re-point the wire, pass it through the second die I5, and attach it by a suitable grip to the second drum II. Then by starting the motor 3| and closing the push button 63 momentarily, he can draw the wire through the die I5. In case the wire slackens suiiiciently to4 allow rearward movement of the rst die I4, it may be necessary to close the push button 5I also. When the desired number of wraps have been formed about the drum II, the motor 3| will be stopped, and the wire will be repointed, passed through the die I6, and attached by a grip to the finishing drum I2. By starting both the motors 3| and 23, and if necessary closing the push button 63 momentarily, several turns of wire may be formed about the drum I2. 'I'he machine will then be stopped and the grip removed. This completes the threading of the machine. The operator will now decrease the pressure at the delivery side of the automatic valves 40 and 4I to predetermined values by turning their respective handwheels 42, whereupon he will start the electric motors 3| and 23. The machine will proceed to draw wire through the several dies, with a predetermined back tension in the wire anterior to each of the dies I5 and I6, the speed of the wire being controlled by the speed of the motor 23. There will be no accumulation of wire except on the finishing drum, and no slipping between the wire and the drums. The hydraulic motors operatewith predetermined luid pressures and a constant displacement, and hence will transmit predetermined torques to their respective drums. As the tail end of the wire passes through the flrst die I4, all load will be removed from the rst drum I0 and its driving motor I8. The spring 50 will immediately open the switch 49, deenergizing the solenoid 46 and closing the valve 45. This will prevent fluid from entering the motor I3, so that this motor will stop, instead of accelerating to a high speed (as would otherwise occur), and full Afluid pressure will be maintained for operation of the motor 20.' The wire will loosen about the drum I0 and will be with-` drawn therefrom by the continued rotation of the drum II. As the tail end of the wire passes the die |5, the spring 62 will open the switch 5I, de-energizing the solenoid 53 and closing the valve 51. This will stop the drum II, and the wire will be withdrawn therefrom by the continued rotation of the finishing drum I2. The

motor 23 will then be stopped, the finished wire will be removed from the drum I2l and the machine will be re-threaded as before.

at a predetermined pressure. It necessarily follows'that the back tension between the drum' I and the second die l5 will be predetermined, since it is equal to the diierence between the constant tension anterior to the drum and the predetermined force applied to the wire bythe drum. Similarly, the tension between the die l and the drum Il will be predetermined, since it is the sum of the predetermined back tension anterior to the die I5 and the constant reactive force of the die. predetermined force to the wire, it necessarily follows that the back tension between this drum and the following diev I6 is predetermined, this back tension being equal to the difference between-two predetermined forces. In this connection it will of course be recognized that under all normal conditions, with the drums neither accelerating or decelerating, the tangential forces on the drums are in equilibrium.

It will now be apparent that the invention provides a dependable multiple-die machine of Sincethe drum Il applies a.

a comparatively simple and inexpensive construction adapted-to draw wire with a predetermined back tension andwithout slipping of the wire on the drums. The pressure reducing and regulating valves 40 and 4| lare of a standard construction Which can be obtained commercially at comparatively low cost. 'I'he hydraulic motors I8 and 20 are relatively inexpensive, since they are of the constant displacement type which requires no complicated adjusting mechanism.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A wire-drawingI machine comprising a plurality of dies, a plurality of rotatable drums to -`draulic motors each of which is connected vto another of the drums to drive the same, and means to supply uid to each of the motors at an independently adjustable predetermined pressure. v

2. A wire-drawing machine comprising a plurality of dies, a plurality of rotatable drums to draw wire through the dies successively, means to drive one of the drums at a. predetermined speed, a plurality of constant displacement hydraulic motors each of which is connected to another of the drums to drive the same, means to supply operating fluid to the motors, and a separate vpressure reducing and regulating valve associated with each mfotor to controlthe pressure of the operating fluid supplied thereto.

3. A wire-drawing machine comprising a plurality of dies, a plurality of rotatable drums to draw ,wire through the dies successively, means to drive one of the drums -at a,predetermined speed, a plurality of constant displacement hydraulic motors each of which is connected to another of the drums to drive the same, means providing a supply of operating uid, pipesconnecting the iiuid supplymeans with the respec- 'tive hydraulic motors, and a separate pressure reducing and regulating valve in each pipe to control Vindependently the pressure of the uid