US2849768A

US2849768A - Method and apparatus for backing-up electrotype shells

Info

Publication number: US2849768A
Application number: US395995A
Authority: US
Inventors: Bungay George Waldemar
Original assignee: Electrographic Corp
Current assignee: Electrographic Corp
Priority date: 1953-12-03
Filing date: 1953-12-03
Publication date: 1958-09-02
Anticipated expiration: 1975-09-02
Also published as: US2909818A; GB759660A

Description

Sept. 2, 1958 e. w. BUNGAY METHOD AND APPARATUS FOR BACKING-UP ELECTROTYPE SHELLS Filed Dec. 5, 1953 5 Sheets-Sheet 1 ATTORNEYS.

Sept. 2, 1958 G. w'. BUNGAY METHOD AND APPARATUS FOR BACKING-UP ELECTROTYPE SHELLS 5 Sheets-Sheet 2 Filed Dec. 3, 1953 INVENTOR. 65mm: 14 BUNGAY zz i fifza ATTORNEYS.

Sept. 2, 1958 a. w. BUNGAY METHOD AND APPARATUS FOR BACKING-UP ELECTROTYPE SHELLS 5 Sheets-Sheet 3 Filed D90. 3, 1953 WATER COOLED INVENTOR. GEORGE W. Bu/va/n NEYS.

Sept. 2, 1958 G. w. BUNGAY 2,849,768

METHOD AND APPARATUS FOR BACKING-UP ELECTRO'I'YPE sHEILLs 5 Sheets-Sheet 4 Filed Dec.- 5, 1953 I QM. NW 3 Wm INVENTOR.

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n Y J Sept. 2, 1958 e. w. B'UNGAY METHOD AND APPARATUS FOR BACKING-UP ELECTROTYPE SHELLS Filed Dec. 3, 195s 5 Sheets-Sheet 5 FIIIIIL W MSIR. WWMEQ A N A A A R.G. 4/ mw A, m M WW E m w W 6 Y/OVI B m A S ATTORNEYS.

United States PatentQ lVIETHOD AND APPARATUS FOR BACKING-UP ELECTROTYPE SHELLS George Waldemar Bungay, New York, N. Y., assignor to Electrographic Corporation, New York, N. Y., a corporation of Delaware Application December 3, 1953, Serial No. 395,995

5 Claims. (Cl. 22-58) The invention relates to a novel method and apparatus for .backing-up" electrotype shells for letter press printmg.

Heretofore great difficulty has been encountered in properly backing-up electrotype shells for letterpress printing. In order to obtain a high quality impression from an electrotype shell the face of the shell must be unwarped. Due to the rapid changes in temperature to which the thin copper electrotype shells are subjected in the backing-up process, and to the difierence in thermal expansion between the shell and the backing metal, a con siderable amount of warpage occurs which causes the face of the shell to be uneven, thereby requiring excessive work on the plate to render its face flat before it is madeready. Presently known methods and apparatus for backing-up electrotype shells do not completely prevent this warpage and large amounts of time and effort are required to correct the defects caused thereby, often to the serious injury of the printing face.

In addition to the above-mentioned requirements it is also desirable that the density of the backed-up shells be uniform, and that all of the plates be backed-up with only a slight excess of metal so as to prevent overfiow of the backing metal. In order to obtain such uniformity it is present practice to apply a considerable excess amount of backing metal to the shell and to shave the plate to the proper thickness afterward. This assures uniform thickness but also often introduces another step into the process. As a result of these additional'operations and because of other time consuming operations (i. e. hand pouring, slow cooling) present methods and apparatus for backing-up electrotype shells are time consuming and costly.

Accordingly, it is an object of the present invention to provide a method for backing-up electrotype shells which avoids warpage of the electrotype shell, produces substantially uniformly thick electrotypes, and produces the electrotype shells more quickly than presently known methods at lower cost, also avoiding the need for cleaning backing metal from the face of the shell or plate.

A further object of the invention is to provide apparatus which will perform the functions of the above method either automatically or under manual control.

More specifically it is an object of the invention to provide a machine which will insure uniform heating of the electrotype shell prior to receiving the molten backing metal. 1

Another object of the invention is to provide a ma- 2,849,768 7 Patented Sept. 2, 1958 ice A further object of the invention is to provide a machine which will rapidly solidify the backing metal after Other objects of the invention will be in part obvious and in part pointed out hereinafter.

The applicants method includes, briefly, placing an electrotype shell upon a supporting surface which is preferably heated but which need not be, pressing downwardly upon the shell at a plurality of spaced points to hold the face of the shell in contact with the supporting surface, pouring the molten backing metal onto the shell and withdrawing the pressure after the pouring is complete. If

it is desired to speed the process a predetermined amount of air may be directed at the shell to bring the molten metal to a plastic sandy condition. backed shell may be cooled by placing it upon a cooled surface and pressure may be applied to the backed shell or plate to prevent warpage during cooling.

Applicants apparatus for carrying out the above method comprises a table having a supporting surface for an electrotype shell preferably heated from underneath by suitable heating means. A plurality of retractable, down- 1 wardly acting rods, or fingers, for exerting a downward pressure on the supporting surface at a plurality of individual points, are located above the supporting surface.

Suitable cooling means are also provided for rapidly I bringing the backing metal to a plastic sandy state after it has beenpoured onto the shell, said means comprising a plurality of air tubes interspersed among the downwardly acting fingers and located directly above the supporting surface for the electrotype shell. A conduit in the supporting structure for the retractable fingers communicates the tubes with the output of a blower mounted atthe rear of the table. A pot for holding and heating the backing metal is preferably located immediately adjacent the table and a pump is mounted on the pot and provided with a heated conduit leading to the supporting surface on the table to pump molten backing metal onto an electrotype shell placed on the surface.

Applicants preferred apparatus also includes a press having a cooled, movable supporting surface for the backed electrotype shell.

type having a water cooled supporting surface mounted on the forward portion thereof. Suitable controlmechanisms are provided to cause the cooled surface to carry the electrotype shell into the press portion where pressure is applied to the shell during the cooling operation. Other suitable control mechanisms are also provided for automatically timing the operation of the pump, the blower, the retractable fingers, the heating means for the supporting table andfor the hydraulic press. The pump timer control is constructed and indexed in such a manner that it indicates the proper hydraulic pressure to be used for the amount of molten backing metal pumped onto the electrotype shell. The apparatus may also be manually operated whenever such operation is desired.

It will be understood that the foregoing general de- 1 scription and the following detailed description as well are exemplary and explanatory of the invention but are not restrictive thereof.

The accompanying drawings, referred to herein and constituting a part hereof, illustrate one form of ap- In addition, the

In the embodiment shown and described the press is of the variable pressure hydraulic In the drawings, in which similar referencesnurneralsrefer to similar parts,

Figure 1 isa front elevation of the apparatus showing the general arrangement of the various parts,

Figure 2 is a plan view, partly in section, taken along;

the line 2-2 in Fig. 1, of the supporting table showing a preferred arrangement of the air tubes amid the retractable fingers,

Figure 3. is a front view showing the face ofthe control mechanism for the pump,

Figure'4 is a side elevation of the apparatus showing the arrangement of the blower apparatus, the actuating mechanism for the retractable fingers, and the path of the air from the blower to the air blast tubes,

Figure 5 is a perspective view of an electrotype shellprior to being backed-up.

Figures 6-9 illustrate the various steps of the applicants method of backing-up electrotype shells,

Figure 10 is the electrical control circuit diagram for the supporting, table apparatus, and

Figure 11 is the electrical control circuit diagram for the hydraulic press apparatus.

Referring, now to the drawings for a detailed description of the applicants method and apparatus and turning.

particularly to Figures 59 there is shown in Figure 5 an electrotype shell 10 prior to the backing-up operation. Although the applicants method may be utilized with any type of electrotype shell the type of shell shown in Figure 5 is a type which is particularly suited for the applicants method. In this type of shell, the edges 11 of the shell 10-are bent upwardly so as to form a tray? like member, the outside bottom of the tray being formed by the face of the shell and containing the printing type which will be impressed upon the paper. In order to insure a proper. bond between the inside bottom 12 of the shell 10 and the backing metal which is to. be ap-- plied-thereto a suitable flux may be applied to the inner surface of the shell, but this is not essential. Y

The shellv is placed upon a smooth perfectly flat supporting surface 20 which is preferably, but not neces-' sarily, heated from underneath to melt the flux on the innersurface thereof. I When the shell is placed uponthe supporting surface 20 downwardly acting pressure is applied at a plurality of individual points 22 uniformly.

operation has been completed the downwardly acting pressure is withdrawn and the heat under the supporting surface is reduced or discontinued.

.If it is desired to speed up the operation a predeterminedamount of cooling air may be directed at the molten metal in the shell to quickly bring itto a'plastie If the molten backing metal is electro--- sandy state. type metal this.sandy condition will occur in the range of 510 to 550 F. The stoppage of the air indicates to the operator that the backing metal has been brought tell the operator to place the shell 10 upon a cooled'supporting surface 25 to effect further cooling of the back? ing metal and shell while maintaining them against warpage. A cardboard sheet 26' may also be placed on the shell to form a backing therefor. cooling operation a forceful, even pressure is applied on the entire surface of the shell by a resilient pad 'to preventthe shell from warping.

Even heating of the electrotype shell During the reduces the warp-.

4 age which would occur if the shell were unevenly heated. The application of pressure to the shell at a number of individual points during the heating and pouring operations holds the shell in proper alignment, speeds up the heating of the shell and prevents any warpage of the shell from occurring. By predetermining the amount of molten backing metal to be poured into each shell the applicants metho'd prevents overflow, achieves uniform thickness, avoids' waste, and the additionof the solidifying' and cooling stepsspeeds up the operation. By applying pressure to the shell during the cooling operation warpage in this operation is also eliminated. The

end result is a product which is uniform and in perfect alignment;

In Figures 1-4, there is shown a preferred embodiment of an apparatus constructed in accordance with the teachings of the applicants invention and designed to carry out'the-method outlined. above. The apparatus includesthree principal parts; a pot 30 for holding and heating the backing metal, a supporting table 40 upon which the principal steps of the method are carried out and a press 70 in which the backed-up electrotypeshell may be further cooled under pressure.

The supporting table 40 includes a supporting surface 41 for the electrotype shell approximately waist high for the convenience of the operator and finished so as to be perfectly flat and smooth. Underneath thesupporting surface 41 there is provided suitable heating means for heatingthe supporting surface. In the form of the invention shown the heating means comprises parallel series of gas burners 42 situated .a short distance underneath the supporting surface. The burners communicate with a gas header 43 mounted on the front of the supporting table 40 and the entire area underneath the supporting surface is provided with a pair ofchimneys 44 which direct the hot gases upwardly and away from the apparatus. A pilot light 45 is provided to ignite the gasescaping from the burners, The heating apparatus is controlled by suitable devices (to be described hereinafter) so as to be normally on except when cooling air is-being directed at the shell.

The table 40 is also provided with a plurality of rodlike retractable fingers mounted so as to be capable of exerting downwardly acting pressure uponthe support- '65 to the plastic sandy condition and acts as a signal toing surface 41. Each of the fingers is individually weighted- 51' and yieldably mounted in a frame '52 in order to conform to any irregularities in the electrotype shell 10. The terminal portions 53 of the fingers 50 are sharply.- pointed to minimize the amount of heat conducted away from the shell during the heating and pouring operations. The frame 52 is mounted to slide upon a pair'of parallel rods 54 depending from an air header 55'locatedabove the supporting surface 41 and is provided with a pin 56 at each end having a lever arm 57 pivoted thereon. Each leverarm is in turn pivoted at itsopposite end to suitable pins 58 mounted on the arms of a yoke 59. The yoke is pivotally mounted on a supporting column-60 located at the rearward portion of the table and is actuated upwardly and downwardly by means of a hydraulic piston and cylinder 61 secured to ghe-opposite end of the yoke 59 and pivoted on the base Interspersed among the fingers 50 area plurality of evenly spaced air blast tubes 63 through which cooling air is directed at the electrotype-shell 10. The tubes 63'are attachedto an air header 55 which is mounted on the upper end of the supporting column 60 for the finger structure. The header 55 and the supporting column 60*are hollow so as to form a conduit 64 by which cooling air may be conveyed to the air blast tubes 63. A centrifugal blower 65 is locatedbehind the supporting table 40 and is so positioned that its discharge conduit 66 communicates with the bottom of the hollow'sup porting structure-andcommunicates through the column 60 and the air header S5-with'the air-tubes.

A pot 30 for holding and heating the backing metal is preferably located immediately adjacent the supporting table. A motor driven pump 31 is mounted on the pot for pumping molten metal to the supporting surface 41 on the table. To this end, the casing 32 of the pump 31 is provided with a long discharge conduit 33 terminating in a nozzle 34 a short distance above the supporting surface 41 of the table 40. In order to prevent the molten metal from being cooled during its passage through the conduit 33 a series of gas burners 35, communicating with the main gas header 43, are provided at spaced intervals along the discharge conduit.

Immediately adjacent the table 40, on a side opposite to that of the pot 30, there is provided a variable pressure hydraulic press 70 having a water cooled platen, or supporting surface 71, for the shell. The platen, or supporting surface 71, comprises the forward portion of the apparatus while the press occupies the rearward portion. water-cooled resilient pad 90 preferably made of silicone rubber. The platen is movable rearwardly so as to lie within the plane of the ram 72 and the resilient pad 90 of the hydraulic press (Fig. 11). To this end, the water cooled platen 71 is provided with a rod 73 having an elongated slot 74 to receive a rectangular shaft 75 mounted on a pinion 76. A hydraulically actuated rack 77 engages the pinion 76 to rotate the pinion and move the platen 71 rearwardly into the path of the hydraulic ram 72. A spring biased solenoid actuated valve 78 controls the flow of hydraulicfiuid to the actuating piston 79 for the rack 77. A similar spring biased solenoid actuated valve 80 controls the flow of hydraulic fluid to the ram piston 81. Each of the valves is controlled by suitable electrical mechanism (to be described hereinafter). A temperature gauge 82 for indicating The press comprises a ram 72 and an upper,-

the temperature of the metal in the pot 30 is mounted on the outer portion of the press 70. A gauge 83 for indicating the hydraulic pressure of the system, is also mounted on the press and a manually operable handle 84 is provided at the front of the press by which the pressure of the press may be varied.

In order to render the apparatus capable of use with various sizes of electrotype shells a timing device 36 is mounted on the press 70 by which the output of the pump 31 may be varied. Since the amount of pressure to be applied to the shell during the cooling operation varies in accordance with the size of the shell being backed and, hence, with the amount of metal poured onto the shell, the face of the pump timing device 36 is provided with a dual set of calibrations 3738 (sec Fig. 3). The inner set 37 of calibrations represent time in seconds while the outer set 38 of calibrations represent pressure in tons. Prior to starting the apparatus the operator sets the timer pointer 39 according to the area of the shell which is to be backed-up and reads off the corresponding pressure for the hydraulic press which he sets by means of the handle 84 and the gauge 83. The apparatus is then ready to start the cycle of operation.

The operation of the apparatus is as follows: the tray shaped electrotype shell 10 is first placed upon the supporting surface 41 of the table 40, the gas burners 42 are ignited and the supporting surface and the electrotype shell are heated from below. At the same time the operator pushes button 1 thereby causing the fingers 50 to move downwardly and exert an evenly distributed pressure on the shell to hold the shell in firm and intimate contact with the supporting surface. When the flux is in proper condition to receive the backing metal, the operator pushes button 2 which starts the pump 31 and causes the predetermined amount of backing metal 24 to be poured onto the electrotype shell. When the pouring operation is completed the fingers 50 are automatically retracted and the gas automatically turned off. At the same'time, the blower is started and a blast of cooling air is directed at the shell through the air tubes- 63 thereby quickly bringing the backing metal to a plastic sandy condition. When the blower goes oif the operator is signalled to transfer the shell 10 to the water cooled platen 71 of the press 70 and he presses the button 6 to start the press cycle. The platen is moved inwardly to a position immediately above the hydraulic ram 72 and when it is in its innermost position completes a control circuit for the ram and causes the ram to rise upwardly thrusting the shell and cardboard backing against the water-cooled resilient pad thereby exerting an even pressure on the entire surface of the shell during the cooling operation. When the operation is completed the ram retracts and the platen is returned to its original forward position. I

Figure 10 shows the electrical control circuit diagram for the operations performed at the supporting table. The control circuit includes four double relays, marked A, B, C and D, two

automatic timers

100, 101 together with double acting relays, one for the pump, and one 101 for the blower, an electric motor 102 for driving the centrifugal blower 65, and electric motor 103 for driving the pump 31, a spring biased solenoid actuated valve 104 for valving a hydraulic fluid to the finger actuating cylinder 61, a solenoid valve 105 for controlling the flow of gas to the heating means and a thermocouple 106 to regulate the temperature of the heat supplied to the supporting surface 41 of the table 40.

The control circuit must first be alerted by closing the manual switch 8 which places the circuit in a starting condition and which also starts the gas burners 42 by energizing the solenoid valve 105 through the manual switch 8, stop button 3, control line 4 (GL4), the lower relay in the blower timer 101, through the thermocouple 106 and across to L2. The thermocouple 106 is set to keep the temperature of the supporting surface 41 at a level which will insure proper heating of the shell 10 but which will not prevent the cooling air from quickly bringing the backing metal to a plastic sandy state. After the operator closes the switch 8 he places an empty electrotype shell 10 on the supporting surface 41 and thereafter pushes control button 1. When button 1 is pushed the coil in relay A is energized closing both the relay switches. the coil thorugh GL4, the top normally closed relay in relay C, top relay A, coil A across to L2. The closing of the bottom relay in A energizes the finger solenoid valve, the circuit being through GL4, the normally closed relay in the blower timer, lower relay A, the finger solenoid and L2. When the finger solenoid is actuated the valve 104 is thrust to its downward position and hydraulic pressure fluid is valved to the underside of the piston in the actuating cylinder 61 and the fluid on the upper side of the piston is exhausted to the return tank thereby moving the piston upwardly and lowering the fingers 50.

' When the operator sees that the flux in the shell is ready to receive the backing metal he pushes button 2 thereby energizing the coil of the pump timer 100 and closing the relay. The closing of the upper relay completes a hold ing circuit for the coil through the circuit GL4, the timing mechanism, the upper relay in the pump timer, the coil in the pump timer over to L2. The closing of the lower relay in the pump timer energizes the coil in relay D through the circuit GL4, the lower relay in the pump timer, coil in relay D, over to L2. When the coil in relay D is energized both the upper and lower relays are closed, the closing of the upper relay completing a circuit to the pump motor through GL4, the lower relay in the pump timer, the upper relay in relay D, the pump motor,

over to L2. The closing of the lower relay energizes the coil in relay D completing a circuit through GL4, the normally closed upper relay in relay C, coil in relay B, the lower relay in relay D over to L2. When relay B is energized the upper relay completes a holding circuit for the coil B through GL4, the upper normally closed relay The top switch completes a holding circuit for in relay'C, coil B, upper relay'B, over to L2. The closing of the lower relay in B puts the blower timer coil in a condition to be energized upon the die-energizing of relay D.

When the pump timer mechanism breaks the holding circuit of the'pump timer coil the relay of the timer is de-ene'rgized thereby de-energizing relay D. When relay D is de-energized the lower relay assumes its normally closed position and completesthe blower timer circuit through CL4, the lower relay in relay B, the blower timer coil, the lower normally closed relay in D over to L2. The closing of the upper relay in the blower timer completes a holding circuit for the blower timer coil through CL4, the timing mechanism, the upp'errelayin the blower timer, the blower timer coil, the lower normally closed relay in D, over to L2. Atthe same time, the normally cl'osed relay' in the'blower timer assumes its open position thereby de-energizing thesolenoid gas valve 105 and the finger solenoid valve 104 turning off the gas and raising the fingers. In its open position the lower relay completes a circuit through coil C through CL4, the lower relay in the timer, coil C and over to L2. When relay C is energized the upper normally closed relay is broken thereby de-energizing relay A and the lower relay in C completes a circuit to the blower motor 102 through CL4, lower relay C, the blower motor, over to L2. After a proper interval of time the timing mechanism in the blower timer interrupts the holding circuit for the coil thereby de-energizing the relay in the blower timer and de-energizing the relay C. When the relay C is de-energized the blower motor is turned off and the'control circuit is in condition to repeat the cycle.

If it is necessary to stop the operation of the apparatus quickly the operator pushes the stop buton 3. When this button is pushedthe entire control circuit is isolated from L1 and all operations come to a halt. Button is pushed by the operator when it is desired to operate the pump manually. Button 5 completes a circuit from CL3 through the upper relay D to the pump motor and operates the motor as long as the operator continues to push on the button 5. Button 4 operates in a similar manner for the'blower, the relay C and the blower motor being energized by the operator as long as he pushes on the'button.

The press control circuit'diagrammed in Fig. 11 includes a press timer 110 with'a double relay, a single relay E, a spring biased, solenoid actuated valves 78 for controlling the flow of hydraulic fluid to the actuating cylinder for the water cooled platen 71, a second spring biased, solenoid actuated valve 80 for controlling the flow of hydraulic fluid to the piston for the ram 72, a contact 111 on the rearward end of the platen 71 for closing a normally opened gap 112 in the circuit at the end of its rearward travel, a normally closed spring contact 113 opened by' the hydraulic ram 72 at the limit of its downward travel, and a stop button 7 and a starting button 6. To put the control circuit in a ready condition the operator first closes the manually actuated knife switch 9. He then places the electrotype shell 19 on the water cooled platen 71 at the forward portion of the press 70. Starting button 6 is then pushed to initiate the cycle of operation;

When the start-button 6' is pushed the actuating circuit for the coil in the press timer relay is energized and both relays in the timer 110 are closed. The closing of the top relay completes a holding circuit for the coil from CLS, through the timing mechanism, the upper relay, the press timer coil, and over to L2. Closing the bottom relay in the timer energizm the relay E through the circuit, CLS, lower relay in the press timer, coil in relay E, over to L2. Whenthe coil E is energized the relay E is closed and the coil circuit for the platen solenoid valve is completed from CLS, lower relay in the press timer, relay E, solenoid coil, and over to L2. Under the influence of the solenoid the valve 78 is moved downwardly to valve hydraulic fluid from the pressure line to the right hand 8 side of the piston 79in the platen actuating cylinder and thefluid on the left hand side of the piston isexhausted' to the return'tank of the hydraulic system. As the piston moves leftwardly the rack 77 secured thereto rotates'the pinion gear 76 which in turn rotates'the square stud 75. The stud 75 causes the slotted lever arm 73 to rotate also and to move the platen 71 rearwardly toward the hydraulic ram 72.

The closing of the'lower relay in the press timer also alerts the solenoid in the ram solenoid valve 80 and puts it in a condition to be energized upon the closing of the normally opened gap 112 in the coil circuit. Whenthe platen 71- has moved to the limit of its rearward travel a contact 111- on the rearward end of the platen closes the gap 112 and energizes the ram solenoid valve 84). Under the urging of'the solenoid the valve 80 moves downwardly and valves hydraulic fluid from the pressure line to the underside of the ram piston 81. At the same time fluid on the upper side of the piston is exhausted to the return'tank of the hydraulic system. As the piston moves upwardly to exert a pressure on the electrotype shell 10 during the cooling operation the normally closed spring contact 113 is allowed to close. The closing of this contact 113- alerts a second holding circuit for the platen solenoid valve 78 to be energized upon the deenergizing of the press-timer relay and relay E thereby holding the platen in its rearward position during the lowering of the hydraulic ram 72.

The hydraulic ram exerts a pressure on the shell for a predetermined time set in the timing mechanism of the press timer 110. When the time is up the time mechanism' de-energizesthe'press timer coil and relays and also de-energizes relay E. When the lower relay in the press timer returns to its normallyopened position the solenoid in the ram solenoid valve 80 is returned to 1 its normal position by the spring and hydraulic fluid from the pressure line is valved to the top of the ram piston 81 while the fluid on the underside of the valve is returned to the tank thereby lowering the ram to its normal position. During the lowering of the ram the platen 71 has been held in its rearward position by the circuit GL5, normally closed spring contact 113, normally closed relay E, solenoid coil and L2. When the ram 72 reaches its downwardly limiting position it opens the spring contact 113 and de-energizes the platen solenoid valve 78. The spring then returns the valve to its normal position, valving fluid to the left hand side of the piston and exhausting fluid from the right hand side of the piston-thereby'moving the piston rightwardly, rotating the pinion 76 leftwardly and moving the platen 71 to its forward position.

It is to-be understood that the form of the invention shown and described is merely a preferred embodiment and that the invention in its broader aspects is not limited to the specific mechanisms shown and described but dethe accompanying claims without departing from the principles of the invention and without sacrificing its chief advantages.

I claim:

1. Apparatus for backing-up electrotype shells including a stationary heated, thermostatically-controlled supporting surface for the electrotype shell, a plurality of individually movable, downwardly acting, yieldable fingers for pressing the face of the electrotype shell in contact with said surface, a pump for supplying molten backing metal to the electrotype shell during the time the shell is held in contact with the supporting surface, and timing means for automatically controlling the volume of metal delivered by the pump.

2. Apparatus as set forth in claim 1 in which the fingers are retractable.

3. Apparatus for backing-up electrotype shells said machine including a stationary thermostatically controlled supporting surface for the electrotype shell, a plurality of downwardly pressing individually yieldable fingers for engagement with the shell to hold the shell in contact with the supporting surface during tthe pouring of backing metal onto the shell, supporting structure for the fingers, and blower apparatus in said supporting structure for directing a flow of cooling air to the backing metal in the shell.

4. Apparatus as set forth in claim 3 having heating means for the supporting surface for the electrotype shell and control means for actuating said heating means during the pouring of the backing metal onto the shell and thereafter for turning off the heating means and starting said blower apparatus for cooling air fiow.

5. Apparatus for backing-up electrotype shells including a stationary supporting surface for the electrotype shell, a plurality of downwardly pressing individually yieldable fingers for holding the face of the shell in contact with the supporting surface, heating means underneath the supporting surface for the heating thereof, a pump for pumping molten backing metal directly onto the electrotype shell, adjustable control means for automatically controlling the volume of metal delivered by the pump, a plurality of tubes above the supporting surface for directing a flow of cooling air at the electrotype shell to cool the backing metal, and a second control means for turning off the heat and for starting and automatically timing the flow of air to the' electrotype upon the termination of pump operation.

References Cited in the file of this patent UNITED STATES PATENTS Jackson Aug. 14, Ringler Apr. 23, Dunton Dec. 14, Nocheck May 16, Keefe Nov. 21', Gounley Mar. 13, Eckersall Oct. 27, Slade Sept. 28, Loesser et a1. July 1, Temmen Oct. 21, Smith June 26, Bungay Dec. 5, Atwood Nov. 19, Huck Mar. 25, Myers Apr. 11, Holmes et a1 Nov. 28, Tama Apr. 6, Bishop Feb. 26, Tyler Apr. 30,

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