US1762177A - Centrifugal casting machine - Google Patents

Description

J.l B. LADD CENTRIFUGAL CASTING MACHINE June l0, 1930.

Filed Jan. 19, 1928 ,2 Sheelzs--SheerI l INVEP'OR Mol.

ATTORNEY- June 10, 1930. 1 B LADD 1,762,177

CENTRIFUGAL CA'ST ING MACHINE Filed Jan. 19, 1928 2 Sheets-Sheet 2 A TTORNE Y Patented June 10, 11930 i UNITED STATES PATENT OFFICE JAMES 1a. Lann, or annmonn,

PENNSYLVANIA, A'SSIGNOR T0 UNITED STATES CAST IBON PIPE & FOUNDBY COMPANY, F BURLINGTON, NEW JERSEY, A CORPORA- TION 0E NEW JERSEY i CENTRIFUGAL CASTING MACHINE Application mea January 19, 192s. serial 110,247,783.

My invention relates to machines of the de Lavaud type for the centrifugal casting of cast iron pipes. Such machines comprise a reciprocating carriage sustaining a Water i box and a rotatable mold, he body of which is enclosed in the `water box. As heretofore constructed such machines have been p'rovided with means for reciprocating the carriage including generally a hydraulic cylingp' 'ler and piston, the speed of which is affected by a varying load, and the primev object of my invention is to provide as a carriage ac tuating means a constant speed motor so as to maintain the carriage at any desired speed of motion, irrespective of varying resistance. A further object of my invention is to provide improved mechanism for reciprocating the` carriage comprising a rope connected to actuate the carriage ,in either direction and actuated preferably by an electric motor and to rovide' in such driving mechanism means on preventing (the carriage from striking the abutments which limit its motion with injurious or destructive force. lgOther ob'ects which I have in view are to protect t e rope against contact Vwith the metal which sometimes issues from the rear end of the mold and for taking up any slack which may form in the rope in such a manner that the take up device is securely held in any position it may assume in taking up slack so that the rope cannot again become slack.

The nature of my improvements will be best understood as described in connection [Si with the drawings which illustrate a portion 'of a"centrifugal casting machine provided with a reciproca-ting carriage actuated by my improved mechanism in which drawings:

Figure 1 is a plan view of the apparatus I@ with the carriage removed.

Figure 2a side elevation of the apparatus with the carriage shown in place.

Figure 3 a sectional view on the line 3-3 of Fig. 2, and

il Figure 4 a diagram representing the electric circuits and appliances .for controlling the electric motor.

A, A indicate beams forming part of the framing of the casting machine and support- D. ing tracks A1 A1. B indicates the water box which constitutes also the carriage supported on the tracks A1 by means of the wheels indicated at B1'. lB2 indicates the mold supported in the water box of the carriage, means for rotatingthe mold not being shown, as they form no part of the present invention. C is the runner by which molten iron is introduced into the mold; C1 an extension of the runner into which metal is poured at the top, for instance, by a ladle D. E and E1 are abutment stops to limit the travel of the motor, the abutment E being shown as provided with a hollow portion e to give clearance to the apron indicated at F, which is attached to the rear lower side of the carriage so as to deflect any metal which may issue from the mold and oep it out of contact with the rope which actuates the mold. G indicates the wire rope which is attached to the mold in such a way as to actuate it in either direction. By preference I make the attachment through springs which will permit of a slight relative movement between the carriage vand the mold in either direction. As shown, the connection is made through splringsl H, H1 surroundingl a rod Gr1 to whic the ends of the rope are attached and abutting against a downwardly extending lug B3 extending from the bottom` of the carriage and forked to embrace the rod as indicated in'Figs. 2 and 3. The rope is actuated by a winding drum I, from 'which it passes over guide pulleys K, K1 and K2 and also over pulleys K3, K4 and K5, forming part of the take up mechanism to be described. The winding drum 1s attached to the shaft I1 to which is also attached a worm wheel I2 actuated by a Worm J secured to a Y shaft J1 which is actuated by an electric motor indicated at J 2.

It is necessary for the proper operation of the mold carriage that there should be no yield due to slack in the driving rope. therefore provide an automatic take up mechanism and to prevent any slackening of therope under any conditions I provide the take vup mechanism with a special device which prevents its backward movement. As shown, my take up device consists of a hydraulic cylinder L, having -in it a piston Yll) L1 from which extends a piston rod L2 supporting at its end a take up pulley indicated at K located between the pulleys K*1 and K4 and to prevent rearward motion of the take up ulley I provide a non-return valve M1 1n the conduit M through which uid under pressure enters the cylinder L.

The stopping and startin of the motor 1n either direction is control ed by a master switch which also controls the speed of the motor and to slow up and arrest the motion of the carriage at either end of its travel so that it will not strike the abutments with injurious `force I provide slow down limit switches 23 and stop limit switches 17 which are actuated by the movements of the carriage through some convenient ap liance, as, for instance, lu s N and N1, I e electric circuits and app iances are clearly indicated in the diagram, Fig. 4, the parts whereof are indicated as follows: 1 is the motor armature; 2 is the direct current power supply; 3 is the shunt field; 4 is the field rheostat; 5 is the starting resistance ;v 6 is the slow down and accelerating contactor; 7 is a two-pole magnetic contactor and 7A Vbeing the normally closed contact of contactor 7; 8 a two-pole magnetic contactor and 8A the normally closed contact of contactor 8; 9 is a dynamic breaking resistance; 10 an operating coil for the slowdown and acceleratin contactor 6; 11 is the normally closed-in ofig position of the master switch; -12 contact of low voltage relay; 13 the operating coil for the low voltage relay; 14 1s the master switch contacts closed in the first pouring or return position of master switch. 15 is the operating coil for the return contactor 8; 17 indicates the stop limit switches and 18 master switch contacts closed on the 2nd point pour and return positions of master switch; 19 is the operatin coil for the high speed contactor 20; 21 is t e main line knife switch; 22 is the control circuit knife switch;

23 indicates the slow down limit switches;

24 is a drum switch mechanically coupled to the master switch 14. l

In operation contact 11 of master switch 14 is closed only in the off position of the master switch, therefore when power is applied at 2 the operating coil of low volta e relay 13 is energized and the contacts 12 1n closing make operation possible through contacts 18 of master switch.

The carriage is of course at rest at either end of its stroke. For actuating the motor to move carriage slowly in either direction the master swltch is thrown vto the first point in either direction, which starts the motor to a slow speed, corresponding to the setting of the field rheostat 4.

When the carriage passes the slow down limit' switch 23l the motor is automatically slowed down to below normal speed by inserting armature resistance 5 and applying full voltage to the, motor shunt field 3. When the stop limit switch 17 is reached by the carriage, the motor armature 1 is disconnected from the lineand the electrical breaking is obtained by inserting resistance 9 in parallel with the armature 1, thus brin ing the motor to a stop.

W ere it is desired to actuate the motor at high speed, the master switch is thrown to the second point in either direction, the limit switches operating in the s'ame way.

The electric motor described is a constant speed motor and apart from the other features of my invention I consider the use of such a motor or of any constant speed motor to actuate the carria e as a distinct improvement in the type o apparatus described. v

Having now described my invention, what I claim as new and desire to secure by Letters Patent, isz" 1. In a machine for the centrifugal casting of pipes having a reciprocating mold carrying carriage, means for reciprocatin the carriage comprising a rope connected to move the carriage in opposite directions and means for actuating t an electric motor. 2. In a machine for the centrifugal casting of pipes having a reciprocating mold carrying carriage, means for reciprocatin the carriage comprising a rope connected to move the carriage in opposite directions, means for actuating the rope including an electric motor and an apron secured to the rear of the carriage for protecting the rope from molten metal escaping from the end of themold. 3. In a machine for the centrifugal casting onf pipes having a reciprocating mold means for reciprocating e rope including carrying carriage, the carriage comprising a rope connected to move the carriage in .opposite directions, means for actuatin the rope including an electricmotor, an eectric circuit system for actuating the motor in either direction comprising a master switch, slow down limit switches and stop limit switches and means controlled by the movement of the carriage for actuating successively a slow down and a stop switch as the carriage approaches the ends of its reciprocatory movement.

4. In a machine for the centrifugal cast- `ing of pipes having a reciprocating mold carrying carriage, means for reciprocating the carriage comprising a rope connected to move the carriage in opposite directions, means y'for actuating the rope including a constant speed electric motor, an electric circuit system for actuating the motor in either direction comprising a master switch, slow down limit switches and stop limit switches and means controlled by the movement of the carriage for actuating successively a slow down and a stop switch as the carriage approaches the ends of its reciprocatory movement. v

5. In a machine for the centrifugal casting of pipes vhaving a reciprocating mold carrying carriage, means for reclprocatm the carriage comprising a rope connecte to move the carriage 1n opposite directions, l

slack in theautomatic means for taking u rope including a stop device or preventing a backward movement of the take up mechanism and means for actuating t e rope including an electric motor.

JAMES B. LADD.

Images