US1809995A - Mechanism for adjusting machine tools - Google Patents

Description

June 16, 1931. H. UNVERDROSS 1,809,995

MECHANISM FOR ADJUSTING MACHINE TOOLS Filed law 12. 1927 Li 6 f /4 *5 72" \NVENTOR v Hermann (/n Ve/c/ross BY 6 A'TTORNEY D 1 UNITED s'rATEsiPATENr Patented June 16, 1931 OFFICE HERMANN onvrmnaoss, or FBANKFORT-ON-THE-MAIN, GERMANY, ASSIGNOR T wnsrmenousn ELECTRIC & manuracrunme comrm, A coaroaanon or PENNSYLVANIA MECHANISM FOR ADJUSTING LIACHINE TOOLS Application filed May12, 1927, Serial No. 190,700, andin Germany May 14, 1926. 2

My. invention relates to mechanismjfor ad justing the tools of machine t001s,-the rolls ment of the adjustable tool or roll; The C011.

The stopping of the motor-takes place autoof rolling mills and the like.

Such adjustments are frequently accom: plished by electric motors which are brought to rest after a certain number of revolutions which correspond with the desired adjusttrol ot'such motors presents certain difficulties to the attendant and assumes a certain skill on his part, because he is obliged while carrying out the adjustmentto watch constantly the instrument which indicates the revolutions of the motor, so that acertain inaccuracy in the adjustment is liable to occur and furthermore inv some of the mechanisms employed more than one attendant is required for carrying out the adjustment.

My invention consists of a mechanism which permits the adjustment ofthe tools or rolls to be carried out in such a way that the attendant makes the desiredsettings prior to the adjusting operation itself on a'counting mechanism, so that afterwards he has only to start the adjusting or, screw-down motor.

matically. The automatic stopping of the adjusting motor after it has performed a definite number of revolutions takes place by the motor driving a counting mechanism stepped 'in decades, the individual decade counting units being" designed'as freely adjustable contacts. The motor isbrought to rest when I all the counting units contacts connected in series make contactsimultaneously. I

An embodiment of my invention as applied to the screw-down device of'a rolling mill is diagrammatically illustrated. in the drawing afiixed hereto. In-rolling mills it is essential that the accurate spacing of the rolls should be capable of being carried out in as simple a manner as possible. I I

Referring to thedrawing it willbe seen that the lower roll 11 of the rolling mill, the drive of which is not shown, is journaled in stationary bearings in suitable standards.

The roll 12 is adjustable in such away that when the screw-threaded spindles 13. are

turned the roll is lowered or raised according to the direction of rotation.v

I or gaps.

'9 by means of notches.

. The adjustment of the roll 12 is effected by means of the screw-down motor 14 which drives the spindles 13 through a worm and worm-wheel 15. A definite number of revolutions of the motor 14 corresponds with a definite spacing of the rolls 11 and 12. As screw-down motorv a three-phase motor is shown in the drawing by way of example,

but it will be understood that any other kind .22 are connected the contacts 23 which are closed when the cont-actor coil 24 is not eX- cited. Instead of the switch 21 a push button with-automatic holding circuit might be employed. p

For adjusting a definite number of revolutions of the screw-down motor or a definite spacing between the rolls an adjusting mechanism is according to my inventionprovided which is designed in the manner of'the well-known decade counting mechanisms.

The single-tooth wheel 31 gears with the .spur wheel-'32 with ten notches or gaps so that for each complete revolution of the wheel 31 the wheel 32 is turned by 1/10th of its circumference. The wheel 32 is also designed as ordinary spur wheel and meshes with the spur wheel 33 having an equal number of teeth. 'The wheel 33 is also constructed as single-tooth wheel and engages the spur wheel 34 which is provided with 10 notches The wheel 34 drives the wheel35 having an equal number of teeth. With the toothed wheels 31, 33 and 35 are combined contact-bearing drums 51, 53 and 55 each fitted with a slip- ring contact 52', 54, 56 which covers about 1/ 10th of the circumference of the drum. Upon the shafts of the three wheels 31, 33 and 35 are mounted adjusting levers or fingers 41, 43, and 45 with'contact brushes 42, 4d, 46. Each of these levers is adapted'to be adjusted in the positions 0 to T he'sha ft 27 of the toothed Wheel 3101' the contact drum 51 is driven by the screw-down motor 15 by Way of the gear wheels 28, for instance with the ratio 1 10 so that the contact drum 51 performs only one tenth, the contact drum one'hundredth and the contact dru1n'55 one thousandth the number of revolutions of the screw-down motor 14. H

The mechanism operates in the following manner: Assuming that the spacing between the rolls 11 and 12 should be 642 111111., this corresponds with 6420 revolutions of the screwdown motor 14. The adjusting lever or finger 45 is then placed into the position 6, the adjusting lever 43 into the position 4, and the adj ustine' lever 41 into the position 2. The switch 21 is now closed. The contactor coil 22 attracts its core so that the contacts 25 and 26 in the stator circuit or the screwdown motor are closed. The motor 14 starts and rotates the contact-bearing drums 51, 53,

55. During each complete revolution of the drum 51 the brush 42- of the finger 41 makes one contact with the slip-ring contact 52. This closing of the contact remains, however, inoperative for the time'being. The position is similar in regard to the contactbearin g drum 53, the slip-ring contact 54 of which makes contact with the brush 44 ot the linger 43 once during each complete revolution. As soon, however, as the slipring contact 56 makes contact with the brush 46 of the finger 45, a circuitis completed from S across'the coil 24, brush 42, contact '52, slip-ring (51, brush 44, contact 54, slip-ring 63, brush 46, contact 56, slip-ring to T. The coil 24 attracts its core and opens the circuit 'ofthe cont'actor coil 22, so that the contacts 25, 26 in the stator circuit of thescrew-down motor are opened and the motor comes to rest. The adjustment of the rolls 11 and 12 is then finished. The attendant has thus only to adjust the levers or fingers 41, 43 and45 and need not trouble about the adjustment of the rolls any more. The screw-down motor comes to rest at the proper time when the desired spacing of the rolls has been attained.

motor may according to my invention be still further improved by reducing its speed stepwise after it has performed a certain number of revolutions. This may, for instance, be attained in the following manner. \Vhen the motor has made 6000 revolutions out of an adjusted 6420 revolutions, a contactor coil 71 is excited by the contact drums and contact brushes on the counting mechanism and inserts by means of the contacts 73 resistor sections 7 5 into the rotor circuit of the motor which were previously short-circuited. By the insertion of this resistor the speed of the screw-down motor is reduced by a certain step. As soon as the motor has performed another 400 revolutions the resistor sections 76 are switched into the rotor circuit by means of the contactor coil 72 and the conne control of the adjusting or screw-down,

tacts 74 so that the speed 01 the motor drops by another step. When the motor has then performed a further 20 revolutions the circuit of the contactor 24 is completed across the brushes 42, 44, 46 and the slip- ring contacts 52, 54, 56, the stator circuit of the motor 14 being opened, as described above.

My improved nrech'anism brings about a great simplification oil the process of rolling and greatly relieves the attendant orreduces the number of skilled attendants otherwise required.

Various 1'1'1oditications and changes may be made without departing from the spirit and the scope of the invention, and I desire, therefore, thatonly such limitations shall be placed thereon as are imposed by the prior art.

I claim as my invention 1. In combination, a member disposed to be set in dilferent positions, an adjusting mechanism, a motor for actuating said mechanism, means for starting the motor, means for varying the speed of the motor, and means actuated by the motor "for stopping it in a predetermined position, said means comprising a train of rotatable members disposed to operate at different speeds, and a correspomling number of adjustable membersdisposed to be set in predetermined angular positions, co-operating contact members carried by the rotatable and'adjustable members, said contact members being disposed to individually effect the operation of the speed varying means and to affect the motor stopping means only when said contact'mei'nbers are actuated into engagement si1m1itaneously.

, 2. In combination with an'adj ustarble member, an adjusting mechanism, a motor for actuatingthe' adjusting mechanism, a control circuit for themotor, a plurality of rotatableswitches connected in series-circuit relation to control said circuit, transmission means interposed between the motor and one ofthe'rotatable switches,and gear mechanism interposed between the switches for connecting said switches in tandem relation, said gear mechanism being disposed to cause the movement of the switches at different speeds thereby to provide a definiterelative position of the series of switches responsive to a predetermined movement of the adjustable member and means responsive to the closure of the individual rotatable switches for controlling the speed of the motor.

3. The combination with an adjustable member ofan adjusting mechanism, a motor for actuating the adjusting mechanism, an electro-magnetic line switch for starting and stopping the motor, a relay disposed to control the energization of the line switch, a circuit for operating the relay, and means actuated by the motor lor elfecting the operation of the relay in response to a predetermined movement of the adjustable member,

ill)

said means comprising a series of rotatable counting discs geared'for operation at different speeds, contact segments carried by the discs, and adjustable contact members disposed in co-operative relation to the movable segments, said contact segments and members being connected in series relation to the relay operating circuit to thereby effeet the operation of the relay to stop the motor in response to the simultaneous engagement of all the contact members and segments and means responsive to the individual engagement of the contact members and segments for reducing the motor speed before a stopping operation is elfected.

4. The combination with an adjustable member, of an adjusting mechanism, a motor for actuating said mechanism, a source of power for the motor, a main switch for connecting the motor to the power source, a starting resistor for the motor, switches disposed to short-circuit the resistor in sections, and a counting mechanism actuated by the motor for controlling the operation of all the switches, said counting mechanism comprising a plurality of rotatable switch elements geared in tandem relation to rotate at diflerent speeds, a circuit for controlling the main switch including all the rotatable switch elements in series relation, and a control circuit for each resistor short circuiting switch in cluding one of said rotatable switch elements, thereby to effect a reduction in the motor speed in response to the closure of one switch element, and the stopping of the motor in response to the simultaneous closure of all the switch elements. 7

In testimony whereof, I have hereunto subscribed my name at Frankfort-on-the-Main, Germany, April23, 1927.

HERMANN UNVERDROSS.

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