DE853891C - Wire drawing machine - Google Patents

Description

Wire Drawing Machine The invention relates to wire drawing machines in particular of the type in which the wire is used for the purpose of gradually reducing the cross section pulled through a series of drawing dies with the aid of rotating blocks or drums will.

It has been found that certain important advantages thereby can be achieved that one in the wire path between each block and the subsequent die maintains a noticeable tension. This so-called Balancing generally improves the wire properties, elongated as a result of the Reduction of stone friction and the resulting heat, the service life the drawing dies and in many cases enables a higher wire drawing speed. In addition, there is often a power saving. When applying countermovement to the wire approaching a particular die must necessarily be directed to the Leaving stone, wire an increased forward pull is exerted, its increase however, it is less than the countervailing amount. To deal with these types of wire drawing machines To get the most benefit, it is important to have the practically highest allowable return to apply whose theoretical limit lies where the one resulting from it Forward tensile strength at break of the wire comes close. Many earlier Attempts to draw wire in this manner have had very little success. the The main problem was the frequent breakage of the wire, and so it was stopped it has so far been necessary, with comparatively only a small countermove and as a result to work with little benefit.

Accordingly, it is an object of the invention to provide a wire drawing machine, which work in an absolutely reliable way with a comparatively high counter-pull able.

Another purpose of the invention is to provide a multiple block machine for drawing wire through a series of drawing dies in more satisfactory Wise and without wire breakage problems with a comparatively high return between every block and the following drawing die is able to work.

To achieve this and other goals apparent to a person skilled in the art is according to the invention in a multiple wire drawing machine, the device that the The drive of the rotating drums regulates and the tangential force on the individual drums, in order to achieve a prescribed forward pull and counter pull in the wire a constant adjustable value, so ... built and arranged, that the torque during acceleration or deceleration of the machine in relation is increased or decreased on the rotating masses. The torque values limited by a control member so that the acting on the wire on the drum circumference Tangential force remains below the respective breaking load of the wire. Preferably the torque changes are such that they reduce the counter-pull below the value which is used during normal pulling at a constant speed. the The final drum of the machine is preferably driven directly, while all the rest Drums are given a regulated torque.

In the drawing, in which an embodiment of the invention is described and like parts have the same numbering, FIG. 1 is a plan view from above on .ein a multiple block machine in partial breakout, Figure 2 is a front view of the machine in partial cut-out, Fig. 3 is a diagram in which the various Blocks torques exerted in the various work phases are recorded, Fig. Q. a somewhat schematic, largely sectioned representation of certain, for Control of the torque exerted on the blocks by valve devices, Fig. 5 is a circuit diagram of the electrical used in connection with the machine Plant, FIG. 6 shows a representation similar to FIG. 1 of a modified embodiment of the machine, Fig. 7 is a front view of the machine shown in Fig. 6 in partial eruption, FIG. 8 is an enlarged partial cross-section along the line 8-8 7, 9 show a circuit diagram of the in connection with the machine according to FIG. 6 to 8 used electrical system, Fig. Io a representation similar to Fig. I Another embodiment of the invention, Fig. i i a front view of the machine according to Fig. 10 in partial breakout and Fig. 12 is a circuit diagram of the in connection electrical system used with the machine according to Fig. i and ii.

The embodiment shown in Figs. I and 2 includes one horizontally longitudinally extending hollow frame or housing 2o, which is used as a carrier for a series of five rotatable blocks 21 and one rotatable prefabricated block 22. This prefabricated block is provided with the usual stripper 23, which is a bundle of finished wire able to carry and facilitate its removal from the block. In order to be more convenient For a discussion of the machine, the six each consisting of a drawing die and a block were shown in FIG. Wire reduction levels in their order by brackets and assigned digits i to 6 marked. Accordingly, there will be an opportunity below, for example to speak of stone i or block 3, etc. each of the different blocks is rotatably arranged around a vertical axis on top of the housing 2o.

An arranged at one end of the housing 2o is used to drive the blocks Electric motor 26 with a horizontally rotatable, preferably of several together coupled sections existing shaft 27 is connected. The wave carries for each block a special screw 28 (Fig. i), which is arranged in a below the block Worm gear 29 engages. The worm wheel for the finishing block 22 is directly on whose vertical spindle 31 is fixed so that it can run at a predetermined speed can be driven. The worm gears for the remaining blocks 21 are each with the housing of a rotating displacement pump with a constant flow rate connected per revolution 32. each pump contains one associated with the spindle of the Block 21 connected rotor. The case 2o forms an oil tank and the structure is such that each pump draws a stream of oil from the container and under one releases regulated pressure again, causing on the pump rotor and the associated Block a regulated torque is transmitted. The gear ratios of the Worm-worm gearboxes are such that the pump housing with something higher speed than required for the corresponding blocks being carried out by the machine in the individual drawing stages Reductions in diameter are to be observed. For the purpose of the regulation described later a small control generator 33 (FIG. i) is directly connected to the engine 26 .driven.

When running in a machine of this type, the wire must first be threaded. This requires sharpening the wire, pulling the tip through the die no. I, fastening the sharpened wire to block no. I with the help of the usual gripper with the motor 26 at a standstill, slowly driving the machine until a few turns of wire on the block No. i are formed, and finally a repetition of these measures for each of the remaining drawing dies and blocks. After threading, the machine must be brought to normal speed. After enough wire has accumulated on the finishing block 22, the machine must be stopped, the wire bundle removed, and the machine accelerated again to normal speed. In a machine that works with counter-tension, the various voltages within the entire machine are interrelated. The invention is based on the assumption that the difficulties previously encountered in counter-pulling machines as a result of broken wire are based to a very large extent on the lack of knowledge of the effect that the rotational inertia of the blocks has on the wire tension during rapid changes in speed. It is therefore proposed that the drive torques imposed on the individual blocks during acceleration or deceleration should be modified in accordance with the rotational inertia and speed of each block in such a way that the various wire tensions remain within permissible limits at all times. For the purpose of better understanding, the invention will be explained using a typical wire drawing scheme. For this purpose, a scheme was chosen to taper steel cable wire with 0.8 to 0.9% carbon content in six drawing stages and at a final speed of 457 m / min from 0.411 mm to 0.160 mm. The values for the counter-pull given in Table A below are such that, on the basis of test data, they each result in a forward pull corresponding to 90% of the breaking strength of the wire, presumably in view of possible fluctuations in the physical wire properties and the other numerous relevant factors represents the practically permissible maximum limit. Table A. Level No. 1 o 1 i 1 2 1 3 4 5 6 Wire diameter in mm ............... 4.11 3.53 3.02 2.57 2, i8 08 1.6 Block diameter in mm ............... 406 406 406 406 4o6 559 Block revolutions per minute .......... 73.5 100.4 139 192.2 259.5 3575 Tensile strength of the wire in kg mm ...... 123 1543 178.2 196.2 208.8 217.9 224.3 Breaking load of the wire in kg ............. 1510 1275 1o16 782 605 451 Forward pull without counter pull in kg ....... 782 731 619 490 373 293 Forward pull with counter pull in kg ........ 782 1148 916 704 544 4o6 Counterweight in kg ........................ 0 694 503 363 281 192 Drawing die reaction with counter-pull in kg .. .. 782 454 413 341 263 214 Tangential force on the block in kg .......... 88 644 553 423 352 4o6 Rotational inertia of the block in kg m '. ... 459 4.59 4.59 4.49 4.49 6.4 (25.3) In Table A above, the drawing die reaction with counter-pull results as the difference between forward pull and counter-pull and represents a measure of the friction and wear on the drawing die.

As can be seen from the table, this drawing die reaction is in alli? ii cases, except for the drawing die no. i, which works without counter-pull, a great deal smaller than the forward pull without a counter pull. It is also noteworthy that the tangential force on the block in all cases, except for the one rotating without counter-pull support Block 6, much smaller than the forward move without a counter move. The two for the rotational inertia of block 6 given values, namely 74o or 2929 kg / m2, apply to the block when it is empty or with a roll of finished wire weighing 227 kg is filled. From the above-mentioned tangential forces on the block, the torques calculated that are used to drive the blocks during normal pulling with counter-pull Need to become. However, for the machine to operate successfully, the torques changed to: Adaptation to the special conditions existing at different times will. So must z. B. in the first stage of wire threading in a drawing die the associated block will receive sufficient torque to pull the wire without pulling resistance pull through while in the second threading stage when the wireless before the Drawing die has been added, an additional one to overcome the counter-pull Torque is required. When accelerating and decelerating the machine is It is of the utmost importance to adjust the driving torque of each block properly to regulate the rotational inertia and normal speed of the block in order to achieve the to keep different wire tensions within permissible limits.

The following Table B has been prepared to show the various values of the drive torque (in mkg) required for the various blocks during certain phases of operation in order to maintain the same wire tensions as in normal wire drawing. Table B. Block No. II z I 3 I 4 5 I 6 Threading i. Level ..................... 159 149 126 Zoo 76 82 Threading 2nd stage ..................... - 233 186 143 l10 113 Pull .................. ............. 18 130.6 112 86 72 113 Acceleration (6 sec) .................. 18.5 131.2 113 87 74 117 (129) Stop (2 sec) ....................... 17.4 128 log 81 65 ioi (65) As can be seen from the table, when changing from one work phase to another, considerable changes are required in the torque of the individual blocks, some of which are very important for successful operation. For example, during the acceleration process, if the increased drive torque required to overcome the block inertia is not supplied to the blocks, the wire tensions within the machine are increased because the wire forces all blocks to accelerate at the same time. Now, however, the forward pull on all blocks except No. i is already set to go% of the theoretical breaking strength of the wire, with the remaining io% being regarded as the highest permissible minimum value in order to make the operation successful from a practical point of view. Obviously it follows from this that any increase in tension during acceleration must inevitably lead to wire breakage difficulties. On the other hand, however, a decrease in tension during acceleration, if any counter-pull is retained, does no harm other than losing the full benefit of the counter-pull during the few seconds it takes to bring the machine up to speed. Therefore, for the sake of reliable operation, the torque supplied to the individual blocks during acceleration is preferably increased to a value that is significantly above the value listed in the table and theoretically required to maintain the respective specified counter-pull, but still below the value for wire drawing without assistance value required by return. The size of this excess beyond the theoretical requirement is not critical. During the stopping of the machine, a reduction in the torque is required at each block and is therefore reduced by the same amount by which it was increased during acceleration for the purpose of simplified control. With an appropriate choice of torque increase and decrease, the counter-pull on the individual drawing dies can be kept slightly lower during acceleration and deceleration than during the normal drawing process. Table C below shows the individual torque changes that are suggested for accelerating and stopping the machine in the wire drawing scheme under consideration and the resulting wire tensions within the machine. As can be seen, these stresses are in each case below those occurring with normal wire drawing; nevertheless, no lots can arise because a considerable counter-pull is always maintained. The digits are based on a period of 6 seconds for acceleration and 2 seconds for stopping. The comparatively short stopping time appears to be desirable for safety reasons, since stopping can be an emergency measure that becomes necessary if a person gets into the machine. Table C. Level No. I 2 I 3 I 4 I 5 6 t Theoretical additional torque ........... 0.55 o .83 1.1 1.52 2.07 - Actual added torque ....... 1.4 2.1 2.8 4.2, 5.5 - Pulling torque ......................... 18 130.7 112.3 85.8 71.6 - Total torque ...................... 19.4 132.8 115.1 go 77.1 - Effective torque ................... 18.9 132 114 89 75 - Tangential force on the block ................. 92.5 650 562 435 369 - Forward pull ............................. 781 1143 gii 695 531 388 Return ................................ 0 689 495 349 261 162 t Zichstein reaction ......................... 781 454 416 346 270 226 Theoretical torque reduction ...... 1.66 2.49 3.32 4.56 6.22 - Actual torque reduction ...... 1.4 2.1 2.8 4.2 5.5 - Pulling torque ......................... 18 130.7 112.3 85.8 7r, 6 - Total torque ........................ 16.6 128.6 iog, 5 81.6 66.1 - Effective torque ................... 18.3 131.1 112.8 86.2 72.3 - Tsn, -ential force on the block. ... .. .... .. .... .. 89.6 644 555 425 356 - Forward train ............................. 781, 1146 913 700 541 401 E Return .................. ............. 0 691 500 358 277 185 t die reaction ......................... 781 455 413 342 264 216 4 shows a valve arrangement which is used to regulate the pressure of the oil delivered by one of the pumps, for example pump no. R, and thus the torque supplied to the associated block. Similar arrangements are of course also provided for each of the other pumps. In the illustrated embodiment, a pipe leads 35 from the unillustrated pump outlet to a chamber 36 in the lower part of a pressure control valve 37. From this chamber 36, an outlet passage 39 leading down into a pipe 40 through which the 01 into the reservoir in the housing 2o (Figure . t) can run back. A pressure gauge 41 is connected to the chamber 36 by means of a pipe 42 in order to indicate the pressure existing in it, which is a measure of the torque applied to the associated wire drawing block. The flow through the outlet 39 is regulated by a valve member 44 which is seated on an above piston 45 which is able to slide vertically up and down within a cylindrical bore 46 located above and in communication with the chamber 36. A shaft 48 extends upward from the piston 45 and is surrounded in its lower part by a light spiral spring 49 which presses the piston downwards. The piston 45 has a through-hole 5o through which a small flow of oil can flow from the chamber 36 upwards into the bore space 46 located above the piston.

This located in the bore space 46 01 is passed through a pipe 52 to a manually adjustable pressure reducing valve 53, which is provided with a controlled by a spherical member 55 inlet 54 and an outlet 57, from which a line 58 is able to return the oil to the reservoir . The valve member 55 is held in the closed position by a compression coil spring 59, and the spring force can be regulated by a manually adjustable screw 6o.

The embodiment illustrated in Figure 4 during operation and apparatus described so far flows discharged from the associated pump 01 through the conduit 35 to the chamber 36 and from there through the outlet 39 and the pipe 40 into the reservoir back. The pressure prevailing in the chamber 36 and acting on the underside of the piston 45 keeps the valve member 4.1 slightly from its seat so that this drainage is possible. In addition, a comparatively small flow of oil constantly flows upwards through the bore 50 into the upper bore space 46 and from there through the line 52 and the reducing valve 53. For a given setting of the screw 6o on the reducing valve 53, the pressure in the chamber 36 remains practically constant despite any fluctuations in the flow in the pipe 35. This is achieved by vertical movements of the piston 45 and the valve member 44, which are caused by the slightest pressure changes in the chamber 36, but this pressure is counteracted by the force of the spring 49 and the pressure of the oil in the upper bore space 46. Even with the slightest increase in pressure in the chamber 36, the valve member 44 is moved upward and allows an increased discharge of oil through the outlet 39, whereby the overpressure is canceled. Similarly, even the slightest decrease in pressure causes the valve member 44 to move downward and to reduce the leakage of oil through the outlet 39, as a result of which the desired pressure is restored. By adjusting the reducing valve screw 6o, the oil pressure above the piston 45 can be changed, which in turn causes the oil pressure in the chamber 36 to change such that the piston is held in its balanced or floating position.

The pressure reducing valves 53 of the individual wire drawing stages are now adjusted so that the correct pressure is maintained in the associated chamber 36 remains to achieve the desired drive torque during the normal pulling process to generate associated block. This setting is usually only changed if if the machine is to work according to a different drawing pattern. But to continue the changes in the drive torque suggested above during threading, Accelerating or stopping the machine are the following described additional devices provided.

According to FIG. 4, the piston shaft 48 carries a second piston 62 which slides in a cylindrical bore 63 in the upper part of the valve 37. This bore is closed at the upper end by a plug 64 which has a bore 65 for receiving the upper end of the shaft. A line 66 connected to the bore 65 is used to return oil to the reservoir. By supplying oil of suitable pressure to the lower or upper side of the piston 62 during certain wire drawing phases, the oil pressure in the chamber 36 can be changed for the purpose of any desired change in the torque supplied to the associated valve. For this purpose, a pressure reducing and regulating valve 68, a four-way valve 69 and a three-way valve 70 are provided.

The valve 68 is of the known type with a valve member which is controlled by a spring-loaded membrane which is subjected to the liquid pressure on the outlet side. Such valves are able to maintain a practically constant outlet pressure of a predetermined size despite large fluctuations in the inlet pressure.

The four-way valve 69 is of the solenoid operated and spring centered type. It has a cylindrical bore 72, an inlet 73 in the central portion of the bore, two outlets 74 and 75 near either end of the bore, and two passages 77 and 78 extending between the inlet 73 and the two outlets 74 and 75 lying points are in communication with the bore. Lines 79 can lead from the outlets 74 and 75 to the oil reservoir. A coil-shaped valve member 81 is slidably mounted within the bore 72, it being usually held in the central position shown by two counteracting tension springs 82 arranged in the bore end sections. In this valve member position, everything 01 entering at 73 is caught within the valve spool, while the two passages 77 and 78 are connected to the outlets 74 and 75 through the bore space 72. Two solenoids AS i and DS i are connected to the opposite ends of the valve member 81. The arrangement of the parts is such that when the solenoid AS i is excited, the valve member is moved in such a way that the inlet 73 is connected to the passage 77, but the passage 78 remains connected to the outlet 75. On the other hand, when the solenoid DS i is energized, the valve member moves in the opposite direction so that the inlet 73 is connected to the passage 78, but the passage 77 remains connected to the outlet 74.

The three-way valve 70 is of the control solenoid operated return spring type. It has a cylindrical bore 84, an inlet 85 and two control passages 86 and 87. Lines 9o leading to the oil reservoir may be connected to the end sections of the bore. A spool-shaped valve member 9i is slidably supported within the bore 84 and is usually held by a tension coil spring 92 at the left end of the bore, as shown. In this position of the valve member, the inlet 85 is closed, while the passages 86 and 87 are connected to one another by the bore 84. At the right end of the valve member 9i sits a solenoid IS i, when excited, the valve member is pulled to the right in such a way that the inlet 85 is connected to the passage 87 through the bore 84.

These various valves are connected to one another by lines in the following manner: From the pump outlet pipe 35 a pipe 94 leads to the inlet of the pressure reducing valve 68 and from its outlet a line 95 provided with a manometer 96 to the inlet 73 of the valve 69. From the pipe 94 a line 98 leads to Inlet 85 of the valve 70 and from its passage 86 a line 99 to the passage 77 of the valve 69. The passage 87 of the valve 70 is through a line roo with the upper part of the bore 63 and its lower part by a line ioi with the passage 78 of the Valve 69 connected.

These various parts are so constructed and arranged that when the block i is to be nudged in threading die # i and the solenoid IS i is energized, oil from line 35 through line 9 $, inlet 85, the Bore 84, passage 92 and line ioo can flow into the top of bore 63. This depresses the pistons 62 and 45, closes the valve member 44 and increases the pump delivery pressure in the line 35 such that the pump can transmit the torque sufficient for threading. If the block is to be accelerated, with the solenoid IS i switched off and the solenoid AS i energized, the reduced pressure prevailing in the line 95 is passed through the inlet 73, the bore 72, the passage 77, the line 99, the passage 86, the bore 84 , the Durchlaß.87 and the line ioo transferred into the upper part of the bore 63. This depresses piston 62 and increases the pressure in line 35 required to maintain flow through outlet 39, which in turn increases the torque normally transmitted by the pump by an amount dependent on the setting of pressure reducing valve 68. Finally, when the block is to be slowed down for the purpose of stopping the machine, the solenoid DS i is energized and thereby the reduced pressure prevailing in the line 95 through the inlet 73, the bore 72, the passage 78 and the line ioi into the lower part of the bore 63 transferred. This pushes piston 62 upward and reduces the pressure in line 35 required to maintain flow through outlet 39, which in turn reduces the torque normally transmitted by the pump by an amount dependent on the setting of pressure reducing valve 68. Since the effective areas at the top and bottom of the piston 62 are equal, the torque addition during acceleration is equal to the torque reduction during deceleration. During normal operation at substantially constant speed, all three solenoids are turned off and both ends of the bore 63 are connected to the drain pipes 79 through the intervening conduits and valve chambers. Under these conditions, the torque transmitted by the pump is regulated by adjusting the relief valve 53.

It is clear that each of the pumps 32 requires such a pressure regulator as shown in FIG. To simplify the description, the five trigger solenoids are denoted by IS i to IS 5, the five acceleration solenoids by AS i to AS 5 and the five stop solenoids by DS i to DS 5. They all appear in the circuit diagram of FIG. 5, which is now to be described.

In this Fig.5 certain electrical apparatus are shown schematically, by means of which the machine can be operated in the desired manner. These include a direct current source 103 with constant voltage that can be switched on by manual switch r04, a motor 26 with the alternating field 105 and the main field io6 and a control generator 33 with the field 107. Two variable resistors iog and i io are mechanically connected to one another for simultaneous adjustment. A line contactor A has a normally open switch A i and a normally closed switch A 2. An in-service contactor B has normally open switches B i, B 2, B 3, B 4 and B 5 and normally closed switches B 6 and B 7. A contactor C for a dynamic brake has a normally open switch C i. An acceleration contactor D has a normally open switch D i and a normally closed switch D2, while a second acceleration contactor E has a normally open switch E i and a normally closed switch E 2. A stop contactor F has a normally closed switch F i. A field acceleration level relay G has a normally open switch G i. A full-field relay H of the delay type (hence designated td) has a normally open switch H i. Two acceleration relays J and K (of the delay type) each have a normally closed switch J 1 and K i, respectively. A delay type stop relay L includes a normally open switch L i. An acceleration relay M contains a normally closed switch 31 1. Furthermore: there are a normally closed stop push-button switch 112 and a normally open in-operation push-button switch 113. A pair of coupled, normally open push-button switches 114 / 115 (No. 1), 116/117 (No. 2), 11ö / 11 () (No. 3), 12O / 121 (No. 4) and 122/123 (No. 5) and further for block 6 a normally open single switch 124 is provided. A resistor 125 is used to support the regulation of the motor 26.

The electrical connections between the various switches and other devices shown in FIG. 5 are as follows: The switch A i, the armature of the motor 26, the alternating field 105, the switches E i and D i and the field acceleration relay G are connected in series the main switch 1o4. The switch C i and part of the resistor 125 are in series parallel to the winding 26 and the field 125. A second part of the resistor 125 is bridged by the switch E i and a third part of the resistor 125 by the switch D i. The field 1o6 and the rheostat iog are in series above the main switch 1o4. The two switches G i and H i are each bridged by the variable resistor iog. The switches 112 and 113 and the in-operation contactor B are in series above the main switch 1o4. Switch B i is bridged by switch 113. The switch B 2 and the line contactor A are in series above the main switch i o4. Each of the switches 114, 116, I I8, 120, 122 and 124 is shunted by the switch B2. The switch B 3, the acceleration contactor D and the switch J i are in series above the main switch 104. The acceleration contactor E and the switch K i are in series parallel to the contactor D. Each of the following groups of components is in series above the main switch 104: the Switch B 6 and the acceleration relay J; the acceleration relay K and the switch D 2, the full-field relay H and the switch E 2; the switch A 2 and contactor C for the dynamic brake; the switch 115 and the push solenoid 'JS i; the switch 117 and the kick solenoid IS 2; the switch i 1g and the push solenoid IS 3; the switch 121 and the push solenoid JS 4; the switch 123 and the push solenoid JS 5; finally the switch B4, the switch M i and the acceleration solenoid AS i. The other acceleration solenoids AS 2 to AS 5 are each parallel to the solenoid AS i. The armature of the control generator 33, the acceleration relay M and the variable resistor i 1o are in series in an independent circuit. The field 107 is bridged by the main switch 1o4. Furthermore, the following additional component groups are each in series above the main switch 104: the switch B 5 and the stop relay L; the switches B 7 and L i and the stop contactor F; Finally, the switch F i and the stop solenoid DS i, to which the other stop solenoids DS 2 to DS 5 are each parallel.

The mode of operation of the embodiment shown in FIGS i and K i, however, are opened. In order to thread the drawing die no. I, the block no. I must be triggered by closing switches 114 and i 15 by depressing the trigger button no. I. By closing the switch 114, the line contactor A is excited, which closes the switch A i and opens the switch A 2, whereby the dynamic brake contactor C i is de-energized and the switch C is opened. Closing switch A i causes motor 26 to run slowly, since the entire field 1o6 is effective when switch H i is closed and the parts of resistor 125 bridged by switches E i and D i are connected in series with the motor armature. Closing switch I15 energizes solenoid JS i so that pump no. I transmits the torque required for threading to block no. I. When the desired number of turns of wire is wound on the block, the push button is released so that switches 114 and 115 open again. As a result, the line contactor A is de-energized, whereupon switch A i opens and switch A 2 closes. As a result, the brake contactor C is excited, the switch C i is closed and the motor is stopped dynamically by connecting part of the resistor 125 in parallel. In a similar way, the other blocks can be pushed one after the other by pressing the appropriate push buttons until the machine has finished threading. Since block no.6 does not have a corresponding pump or push solenoid, its push button only actuates the simple switch 124. Obviously, when threading the drawing dies no.2 to 6, the preceding blocks only require the normal operating torque because, as can be seen from FIG is that the counter-pull to support their rotation is available as soon as the wire has stretched enough around them to give a playful effect.

As shown graphically in Figure 3, each changes torque given to the first five blocks when changing from an operating phase to the other. For example, each block needs a .Block in the early stages of threading just enough torque to pull the wire off the next block without any help can be pulled through the drawing die. When then the lots are added is, increases in all blocks except for block i the torque to .den for to create the counter-move required for the previous block. As soon as the following Block is threaded and in turn delivers counter-tension, the torque is so far as it is necessary for the normal pulling process with counter-pull.

The diagram shows that each block during acceleration one additional torque and a reduced torque is given during stopping. The sections of the line that are parallel to the abscissa indicate that the torques remain the same for the duration of the relevant operating phase.

After threading is complete, the machine is ready for operation and the operator only needs to press the in-service pushbutton to temporarily close switch 113 so that all switches B i to B 5 close by energizing the in-service contactor B , however, switches B 6 and B 7 open. The closed switch B i maintains the energization of the contactor coil B upright. The closed switch B 2 energizes the line contactor A, whereby the motor 26 comes into slow gear. The closed switch B 4 energizes all acceleration solenoids AS i up to and including AS 5, so that all pumps 32 give their associated blocks the correct acceleration torque required to overcome the rotational inertia. The extent of the additional torque beyond the normal operating torque is determined in each case by setting the associated pressure reducing and regulating valve 68 (FIG. 4). By opening the switch B 6, the acceleration relay I is de-energized, and after its delay time has elapsed, the switch I i closes and energizes the acceleration contactor D. As a result, the switch D i closes, short-circuits the corresponding part of the resistor 125 and thus increases the Engine speed. At the same time, the acceleration relay K is de-energized by opening the switch D 2, and after its delay time has elapsed, the switch K i closes and energizes the acceleration contactor E. Now the switch E i closes, short-circuits the corresponding part of the resistor 125, whereby the Engine comes to its base speed. At the same time, the switch E 2 opens, whereby the full-field relay H is de-energized. After its delay time has elapsed, the switch H i opens and allows the variable resistor iog to take effect, so that the motor field io6 is reduced and the motor is accelerated to the speed gated by the setting of the variable resistor. During this operating period, the relay G controls the amount of acceleration. If this extent exceeds a predetermined value, the armature current is large enough to allow the relay to become effective, whereby the switch G i is closed, the field control resistor iog short-circuited and the field io6 is strengthened. This in turn reduces the armature current and switches off the relay G. This sudden attraction and release of the relay continues until the motor has reached its set speed. At this point in time, the control generator 33 driven by the -Niotor 26 has attained the speed required to deliver the voltage required to respond to the acceleration relay. This opens the switch M i and all five acceleration solenoids AS i to AS 5 are de-energized. As a result, the pumps 32 transmit to their associated blocks the normal operating torque that is determined by the setting of the associated reducing valves 53 (FIG. 4). Thus the machine will continuously work everywhere with the predetermined counter-pull.

When enough wire has accumulated on the finishing block 22, the operator stops the machine and removes the wire bundle. The machine can be stopped by simply pressing down the stop button, whereby the switch i 12 is suddenly opened. As a result, the in-operation contactor B is de-energized, which opens switches B i to B 5 and closes switches B 6 and B 7. By opening the switch B 2, the line contactor A is de-energized, the switch A i opens, the switch A 2 closes, whereby the brake contactor 'C is energized and the switch C i is closed. As a result, the motor is stopped very quickly through dynamic braking. Closing switch B7 energizes delay contactor F and closes switch F i, whereby all delay relays DS i to DS 5 are energized, which in turn reduces the torque exerted by each pump 32 on the associated block and slows down each of these blocks Caused cycle with the motor 26. By opening the switch B 5 , the delay relay L is de-energized and drops out shortly after the motor comes to a standstill. The switch L i now opens, the delay contact generator F is de-energized, the switch F i opens and the delay solenoids DS i and DS 5 are de-energized.

In the direct coupling of the block 6 to the motor 26 in front of one of the preceding blocks, there are important advantages. If the direct drive were to be on one of the first five blocks, block no. 6 would have to be given a regulated torque which would have to be changed during acceleration and deceleration depending on the changes in the block moment of inertia, which on the one hand largely changes changes according to the amount of finished wire on the block. Furthermore, when the machine starts up, the direct drive block would tend to start up a moment earlier than the hydraulically driven blocks, thereby giving the wire causing the direct drive block enough slack to cause a momentary loss of capstan on that block. As soon as the following blocks would have picked up this wireless, the capping effect would be restored all of a sudden and a violent jolt in the wire immediately in front of the directly driven block, combined with a possible wire break, would occur. Another advantage of the preferred embodiment is that the feed speed of the finished wire is determined directly by the speed of the motor 26, which can be changed by setting the field control resistor 109. Such a change in setting causes a corresponding change in the variable resistor I Io, so that the relay M will respond at the correct motor speed.

The invention obviously provides a reliable multi-block wire drawing machine that is able to work with a comparatively high wire counter-pull. Wire break as well as wireless during acceleration or deceleration are really avoided, and is precise regulation of wire tension across the machine achieved.

6 through 9 is a modified embodiment of the invention described, for which, as far as applicable, various reference symbols from Fig. I. are used. So there are the frame or the housing 2o, the five blocks 21, the Finishing block 22 with its stripper 23 and the six drawing dies 24 are present. the The machine is driven by the electric motor 26 with which the small control generator 33 is directly coupled.

In this embodiment, each of the six blocks is at the top attached to a vertical rotatable spindle 13o on which a worm wheel 131 is attached. The snails of the first five blocks each stand horizontally Worm 132 in engagement, while the worm wheel for the finishing block 22 with a horizontal screw 133 cooperates. The motor 26 drives a horizontal, in suitable bearings 136 resting shaft 135, which are preferably composed of several, with one another coupled _ \ sections. The screw 133 for the finishing block 22 is for the purpose of Creation of a direct drive for this .Block attached directly to the shaft 135 a11. The screws 132 for the blocks 21, however, are each made hollow (see Fig. 8) and rotatably supported in mating bearings 137 so that shaft 135 axially closes them able to enforce.

In order to be able to transmit a specific, regulated torque from the shaft 135 to each individual worm 132, the following means are used: Each worm I32 is at one end with the driven member 139 of a suitable magnetic slip clutch I4o (FIG. 8), for example of the known type Eddy current principle, connected. Each of these five clutches contains a drive member 141 which is fastened to the shaft 135 and carries an excitation coil EC 1 or EC 2 to EC 5 corresponding to the associated blocks Nos. I to 5. Each coil receives current in a known manner via a pair of brushes 143 which bear against a pair of slip rings which are carried by the shaft 135 and are connected to the coil ends. The slip rings are of course isolated from each other and from the shaft. The amount of torque transmitted by each clutch 140 depends on the extent to which its coil is energized. The speed ratios of the various worm gears are such that each worm 132 rotates somewhat more slowly than the shaft 135 when the particular wire drawing scheme suitable for the machine is carried out. With a normal continuous pulling process, there is some slip in every clutch.

In Figure 9, the control mechanism for the motor 26 and the various magnetic clutches is shown in the diagram. Many parts of the arrangement are the same as in Fig. 5, and therefore the same reference symbols have been used as far as possible. There is therefore the electrical power source 103 and the main switch 104. The motor 26 has an alternating field 105 and a main field io6. The control generator 33 has a field 107. There are also two mechanically connected variable resistors iog and I1o, a stop push button 112, an in-operation push-button I 1 3, push-button switches 114 to 124 for triggering purposes, a line contactor A, an in-operation contactor B but without the switch B 7 present in Fig. 5, a contactor C for dynamic braking, two acceleration contactors D and E, a motor control resistor 125, a field acceleration relay G, a full-field relay H, two acceleration relays (with lagging) J and K and an acceleration relay M. As additional equipment, not required in the arrangement according to Fig. 5, there are two torque increasing relays N and O, two torque reducing relays P and Q, five torque control resistors RH I to RH 5 and five torque control resistors RE 1 to RE 5. The relay N actuates six Switches N '1 to N 6, the relay O five switches O 1 to O 5, the relay P six switches P 1 to P 6 and the relay Q have five switches QI to Q 5. All switches NI to Q 5 are normally open. The two relays O and Q work, as indicated by the additional designation td , with a time delay.

The electrical connections between the various parts in the upper portion of Fig. 9 correspond to those in Fig. 5, and therefore repeated description appears unnecessary. This applies to the lines to the motor 26, control generator 33, stop button 112, in-operation button 113 and to the variable resistors iogund i 1o, contactors A, B (except for switches B 4 and B 5), C, D and E. and relays G, H, J and K. The following additional series circuits via the main switch 104 are available: switch B 4, switch M i and relay N; Switch N 6 and relay O; Switch B 5 and relay P; Switch P 6 and relay Q; Variable resistor RH i, resistor RE i and clutch coil EC i; Variable resistor RH 2, resistor RE 2 and clutch coil EC 2; Rheostat RH 3, resistor RE 3 and coupling coil EC 3; Variable resistor RH 4, resistor RE 4 and coupling coil EC 4; Variable resistor RH 5, resistor RE 5 and clutch coil EC 5. The push-button switches 114, 116, 118, 120 and 122 are each parallel to the associated resistor RE i, RE 2, RE 3, RE 4 or RE 5. Each of the push-button switches 115, 117, II9, 121, 123 and 124 is parallel to switch B2. Each of the switches N i, O 1, P i and Q i is parallel to a different part of the resistor RE i, one fifth of which remains unbridged. The same regulation or subdivision of the resistors RE 2 to RE 5 is carried out by the corresponding numbered switches N, O, P and Q.

During operation of the embodiment shown in FIGS. 6 to 9, after closing the main switch 104, block no. I can be triggered for the purpose of threading in that switches 114 and 115 are closed by actuating the trigger button no. I. Closing the switch 115 energizes the line contactor A and, as has been described in the first embodiment, causes the motor 26 to start slowly. The closed switch 114 switches off the entire resistance RE i and thereby outputs the clutch coil EC i enough excitation to provide ample threading torque to block # i. The remaining blocks are pushed in a similar way until the machine is completely threaded. The in-service push-button 113 is now operated, thereby energizing the in-service contactor B and accelerating the motor in the same manner as described in the first embodiment. Closing switch B 4 energizes relay N and closing switch B 5 energizes relay P. When switch N 6 is closed, relay O is energized and when switch P 6 is closed, relay Q is energized. As a result, all switches for the relays N, O, P and Q are closed, and the associated sections of the resistors RE i to RE 5 are short-circuited. With a suitable setting of the various resistances, this results in the correct excitation for the various clutch coils in order to give the appropriate torque to accelerate the associated blocks. As soon as the motor 26 and the control generator 33 have attained normal operating speed, the relay M engages, opening its switch M i and breaking the circuit to the relay N. When this relay trips, all switches N open and the circuit to relay O is interrupted. When the delay period of this relay is over, all 0 switches open. In this way, additional sections of the resistors RE i to RE 5 are effective in two successive stages in order to return the excitation of the associated clutch coils and thus the torque for the associated blocks to the value for normal operation.

To stop the machine, only the stop button 112 needs to be actuated. As a result, the in-service contactor B is de-energized and drops out immediately. When the switch B 2 is opened, the line contactor A is de-energized and the motor suddenly stops under the influence of the dynamic brake, as has been described in the case of the earlier arrangement. When the switch B 5 is opened, the relay P fails, as a result of which all P switches are opened and the associated RE resistor sections are effectively grounded in order to reduce the excitation of the EC coils. When switch P 6 is opened, relay Q is de-energized, and after its delayed release, all Q switches open, and further sections of the RE resistors take effect in order to reduce the current flow through the EC coils. Thus, with the correct setting of the various resistances, the torques transmitted by the clutches 14o to blocks nos to cause it to be slowed down.

10 to 12, a further embodiment of the invention is shown, where, where appropriate, certain reference numerals of Fig. I have been used. So there are: the frame or the housing 2o, the five blocks 21, the finishing block 22 with the stripper 23 and the six drawing dies 24. Each block sits at the upper end of a vertical, rotatable spindle iso with a worm wheel 151 attached to it A worm 152 meshes with the worm gear and is driven for each of the blocks No. I to 5 by a more independent electric motor BM i to Bj'lT 5 and for the finishing block No. 6 by an electric motor BM 6 . The speeds and force characteristics of these motors as well as the speed ratios of the various worm gear drives depend on the particular wire drawing scheme for which the machine is to be used.

As can be seen in particular from FIG. 12, the motor BM i has a commutator field CF i and a main field MF i. The motors BM 2 to BM 5 are not particularly shown in the figure; but they are arranged in the same way and have the main fields MF 2 to MF 5. The motor BM 6 is provided with the commutator field CF 6 and the main field MF 6 . The main generator 155 is used to supply current for the various block engines with the commutator field 156 and the main panel 157. In connection with the block No. i -. Motor BM i is an Nachschiebegenerator BG i with a commutator field 159 and a main field 16o and henceforth a regulator Reger RG i with a main field 161 available. This exciter RG i is preferably of the well-known amplid type. The generators 155 and BG i are driven by the motor 163 and the exciter RG i by the motor 164. The purpose of controlling six line contactor LC i are with normally open switches LS i to LS 6 is provided to LC 6, the switch LS i, the block motor BM i, be commutator field CF i, the Nachschiebegenerator BG i and its commutator field 159 are connected in series to each other and parallel to the main generator 155 and its commutator field 156. A variable resistor 166 with an ohmic drop bridges the commutator field CF i of the block motor BM i. A resistor 167 bridges the supply generator BG i and its commutator field 159. The excitation field 161 lies between the tap of the variable resistor 166 and an intermediate point on the resistor 167. The field 16o of the supply generator is in series with the regulator exciter RG i and a resistor 168 Circle. The other block motors BM 2 to BM 5 are switched in the same way as the block motor BM i; they each have their own replenishment generator and regulator exciter and are controlled by the associated switches LS 2 to LS 5. The switch LS 6, the block motor B.11 6 and its commutator field CF 6 are in series with one another and parallel to the main generator 155 and its commutator field 156. This arrangement forms a Ward-Leonard or controllable voltage control for the block motors.

There are also: a constant voltage direct current source 170 under the control of a main switch 171; six field control resistors FR i to FR 6, which are each connected to the associated block motor field MF i to MF 6 in series with one another and parallel to the main switch 171; a trigger relay IR with a normally open switch JR i and an in-service relay RR with a normally open switch RR i. A variable resistor 173 for the main generator field and a switch 174 are mechanically connected to one another in such a way that the switch 174 is opened when the variable resistor 173 is in the "Off" position and closes as soon as the variable resistor moves slightly in the direction of the "Operation" position has been. This variable resistor 173, the switch RR i and the main generator field 147 are in series with one another via the main switch 171. The switch IR i and a resistor 175 are in series with one another and in parallel with the variable resistor 173 and switch RR i. The switch 174 and the relay RR are in series with one another via the main switch 171. For each of the six block motors there is a special push button which actuates two normally open switches. The switches for the push button no. I are denoted by i J i and 1 I 2, the switches for button no. 2 by 2 J 1 and 2 1 2 and so on up to 6 J i and 6 J 2. Each of the six block motors also has a special selector which actuates two switches that are mechanically coupled in such a way that when one switch is open, the other is closed and vice versa. The switches for selector no. I are denoted by i S i and i S 2, the switches for selector no. 2 by 2 S 1 and 2 S 2 and so on to 6 S i and 6 S 2. The switches i S i to 6 S i, which can be referred to as “in operation” switches, are each in series with the associated line contactor LC i to LC 6 above the main switch 171. The switches 1 S 2 to 6 S 2 , which can be referred to as "off" switches, are each connected to the associated switches i J i to 6 J i in series with one another via the respective corresponding on-operation switch i S i to 6 S i. The switches 1 J 2 to 6 J 2 are parallel to one another and in series with the trigger relay JR via the main switch 171.

The mode of operation of the embodiment shown in FIGS. 10 to 12 results from the following description: It is assumed that the motors 163 and 164 are running, that the main switch 171 and all selector switches i S 2 to 6 S 2 are closed and that the main field control resistor 173 is in the "off" position. The field control resistors FR i to FR 6 must be set so that they give the corresponding block motors the correct start-up speed. In order to thread the drawing die no. I, the operator pushes block no. I by pressing push button no. I and thereby closes switches i J i and i J 2. By closing the switch i J i, the line contactor LC i is excited and closes the line switch LS i. By closing the switch 1 J 2, the trigger relay RR is energized, whereby the switch JR i is closed and the main field 157 is energized to the extent determined by the size of the resistor 175. Since the voltage supplied by the generator 155 is comparatively small, the motor BM i for block no. I will run at a correspondingly slower or starting speed. After threading the die no. I, the operator releases the push button no. I and closes the switch i S i for the selector no. I, whereby on the other hand the switch i S 2 closes. The trigger relay IR drops out and opens the switch JR i. The line contactor LC i remains excited and the switch LS i closes, but the block motor B_ll i stops because the main generator field 157 is de-energized. For the purpose of threading the die no.2, the operator now pushes block no. 2 by pressing down the push button no.2 and closing switches 2 J i and 2 J 2. As a result, the line contactor LC 2 and the trigger relay RR are energized, the switches LS 2 and IR i close, and the two block motors BM i and BM 2 run at low speed. After the drawing die no. 2 has been threaded in, the push button no. 2 is released and the selector switch 2 S i is closed. This causes the switch 2 S 2 to open and the motors for blocks nos. I and 2 to stop.

When all the drawing dies are threaded and all selector switches i S i to 6 S i are closed, the machine is ready to accelerate to normal operating speed. For this purpose, the operator moves the arm of the main field control resistor from the "Off" to the "In operation" position. When the arm begins to move, switch 174 closes, energizing in-service relay RR and closing switch RR i. In this way, the main field 157 receives a gradually increasing and finally full excitation as soon as the regulator arm reaches the "in operation" position. Since all line switches LS i to LS 6 are closed, all block motors BM i to BM 6 also start and accelerate under the influence of the increasing voltage imposed on them by the main generator 155 until normal operating speed is reached. When the machine is to be stopped, the arm of the variable resistor 173 is turned back into the "off" position, whereby the switch 174 is opened and the in-service relay RR is de-energized. The switch RR i now opens and the main generator field 157 is de-energized, as a result of which the block motors stop by means of regenerative braking.

The speed of a DC motor with constant field excitation is proportional to its counter electromotive force, the so-called back EMF, namely the voltage generated by the motor winding and opposite to the voltage applied Tension. The difference between the applied voltage and the back emf is the voltage required to overcome the armature resistance, the so-called IR drop, which is equal to the product of armature current and armature resistance. If the The speed of such a motor is changed by changing the applied voltage the speed change achieved is not in exact proportion the voltage changes because the back EMK always smaller by the amount of the IR drop than the applied voltage. In a wire drawing machine with individual block motors motors with different power ratios are usually required therefore also have a different IR drop. This IR drop will now compensated by the follow-up generators, which give the associated motors a impart additional voltage appropriate to the IR drop and relate them to it with the regulator exciters, an additional one during the acceleration period and to provide reduced torque during the deceleration period to to compensate for the inertia of the blocks and motors. Because the field 161 of the pathogen RG i is switched so that its excitation is related to the flow of current through the motor Bell i changes, the pathogen causes corresponding but intensified changes in the Excitation of field 16o of the supply generator. This is the one generated by it Voltage changed and the block motor forced to perform bz-, v. Slow down to make the required torque changes. During the normal wire drawing at a constant speed, this is the case with every block motor its associated block delivered torque on a constant desired Size kept by setting the associated motor field control resistor is predictable. As a result, the desired stresses in the wire are over maintain the whole machine. The return can be so relatively high Values are set so that the required forward pull is close to the breaking limit of the wire and thus the advantages of counter-pull wire drawing are fully exploited can be.

It can be seen that the invention is novel and extremely represents advantageous design of a multiple block wire drawing machine. The wire tensions are at the desired value at all times and across the entire machine and the torques given to the blocks when the speed changes are changed so that the risk of wire breakage is negligible. While only three embodiments of the invention have been described exist for the Expertise in the light of our invention disclosure and within the scope of protection numerous other amendments to the claims.

Claims (3)

PATENT APPLICATION (: HF: i. Device to work with a multiple wire drawing machine to regulate the drive of the drums and that exerted on the individual drums Torque corresponding to a prescribed forward pull and counter pull in the wire to keep at a constant, adjustable value, characterized. that the individual drum when starting or stopping the @lascliine a torque is granted, which increases or takes into account the rotating masses is reduced and its predeterminable '' values can be set by a control element and can be limited in such a way that the tangential forces acting on the wire around the drum circumference Do not exceed the breaking load of the wire. 2. Device according to claim i, characterized in that the torque changes. the legs of the drums Starting and stopping issued to the machine are such, that the counter-pull in the machine remains constant with its normal pulling process Speed value that occurs remains. 3. Device according to claim t, characterized in that the final drum of the machine is driven directly and each of the other drums is given a regulated torque. Energized publications:. USA. Patent No. 2 185, 4i6.