US1355879A - Mold for printers' leads and the like - Google Patents

Description

J. S. BANCROFT AND A. L.'KNIGHT. MOLD FOR PRINTERS LEADS AND THE LIKE.

APPLICATION FILED JAN-14,1918. 1,355,879, Patented Oct. 19,1920.

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JOHN SELLERS sancnorr am) mos LESLIE KNIGHT, or PHILADELPHIA, PENNSYL- VANIA, nssIGNoRs r0 LANSTON monor rn MACHINE comrmy, or PHILADEL- PHIA, PENNSYLVANIA, A CORPORATION OF VIRGINIA.

MOLD FOR PRINTERS LEADS AND THE LIKE.

Specification of Letters Patent.

Patented Oct. 19, 1920.

Application filed January I4, 1918. Serial No. 211,880.

To all whom it may concern:

Be it known that we, JOHN SELLERS BAN- CROFT and Arms LESLIE KNIGHT, both citizens of the United States, and residents of Philadelphia, county of Philadelphia, State of Pennsylvania, have invented certain new and useful Improvements in Molds for Printers Leads and the like; and we do hereby declare the following to bee full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part of this specification,

and to the characters of reference marked thereon.

This invention relates to mold apparatus for elements of printing forms, particularly to molds of the type disclosed, for exam 1e, in United States Letters Patent 0.

1,222,415, dated April 10th, 1917. Molds of this type are adapted as part of a type casting machine to produce printers strip material in the form of rules, leads and like elements of a printing form in fused sections or increments to form strips of indefinite length or in non-fused sections of predetermined length.

The patented apparatus, generally speaking, comprises a mold having an opening for the entrance of molten metal and being open at one end for the exit of the congealed metal means for feeding forwardly the congealed metal and means for forcing molten metal behind the forwardly fed congealeol metal. The operations of casting and feeding are carried on in timed relation to each other and are repeated in accordance with the amount of product desired. For feeding the congealed metal a reciprocatory mold blade is shown in the said patent, which blade advances when the metal in the mold cavity is congealed, to push said metal forwardly toward the exit opening of the mold, and retreats thereafter to leave a cavity for the reception of the molten metal to form the succeeding cast.

In casting typemetal strip material having a printing surface, a matrix formed to produce such surface is used, while in the case of non-printing material it is usual to employ a blank matrix.

Molds of this kind for producing printers strip material are well known commercially and are successful in producing ma terial of the point sizes in ordinary commercial use. When material of a lesser these conditions make it point size is attempted, however, the result is not unlformly satisfactory. In this case the mold cavity frequently has considerable length and a height which is usually eithertype high or low quad high, but the width or point size dimension tively very small: consequently, molten metal 1njected into this cavity has to fill up a space of considerable volume and in dong so 1t must flow in a condition approaching a film between two ordinarily watercooled cavity side walls spaced only slightly apart. It will readily be appreciated that diflicult to produce satlsfactory strip material, particularly that of the cavity is relaof the fused increment kind; the heat contained in the film of injected molten metal is dlssipated more rapidly than desirable. It may here be stated that these molds are commercially used for producing material of polnt s1ze as low as two points and that the lesser point sizes referred to may be roughly considered as less than two points: but 1t is to be understood that the scope of the present invention is not intended to be necessarily limited to apparatus for producing material of thickness less than two points.

The object of the present invention is to provide apparatus especially adapted for the production of the lesser point sizes of lead and rule material and the like, particularly apparatus of the general form of the patented apparatus already referred to, this object being accomplished in the preferred manner by the provision of heat retarding means located in proximity to and at the side of the mold cavity. This object will more clearly be set forth and explained in connection with the following description of the embodiment of the invention shown in the accompanying drawings in which- Figure 1 is a sectional view of a mold of the patented type referred to, the section being substantially in the plane of the mold blade.

Fig. 2 is a cross section of the mold, the section passing through the nozzle opening and also through parts of the pressure screw clamping device.

Fig. 3 isa plan view of tion retarding member.

Fig. 4 is an elevation of the rear face of said member, and

Fig. 5 is an elevation of a portion of the rear face of a modified heat retarding mm,

-the

j the mold base are the rear and ront type. such as leads.

'the mol gate from the side of the strip, especially, 18 passing through the front Q asst-ma bindin during the movement of the ate ber. towar the exit of the channel. ere

Like reference characters in the several the front type block is madein two' sections,

figures indicate the same parts. as justdescribed the upper section 9 is pref- Inasmuch asapparatus substantially corerablymade rigid with the lower section 10 responding to that of the patent hereinby bein before mentioned has goneinto extensive ported y an upwardly extending portion public use and is well understood in the art, 10 of the section 10, to which it is. connected it is thought to be unnecessary to illustrate by screws or other suitable fastenings, as

herein 0 crating mechanism or stops for shown clearly in Fig. 2.

blade and means whereby the The two type. blocks formin between molten metal is injected into the mold' them the mold cavity and mold b ade chancavit nor is it necessary, for 'an.under-\I)1el are positioned laterally of the mold stan ing of the present improvement, to use bypacking plate 17 lace back .of the illustrate in detail means for severing the reartypeblock and by t e ressure screw (projection 4 as operating mechanism and the metal meltof the mold base and adapts 'to" operate ing and in ecting mechanism may s'ubstan--. against the front type block. This prestially correspond to mechanism found. in sure screw, in the referred construction,-is

the t pe castin 'machines manufactured by ,pperated 'periodica ly in time with the feedanston l\ onotype Machine Company, ing of the elementbeing cast so as to clamp which have been in extensive public use for the walls of the mold cavit together durin many years. the casting operation an to release suc Referring to the ac'compan in drawings, pressure during the feedof the element forit will be seen that the mol il ustrated in wardly in the mold cavity. Figs. 1 and 2 embodies a mold base block 3, The bottom of the mold cavity is formed which is formed with a channel there by the mold base and is provided with a through in the direction ofmovement of nozzle. opening 20 through which themolten the mold blade, thus providing-front and metal is injected into the mold cavity rear upwardly extending portions which through a nozzle 20'? indicated in dotted are adapted to be connected across the top lines 1n Fig. 1. I v of the mold by a tie bar or bars 5. Gon- The mold illustrated. is adapted for the fined within the channel extendin through making of material of less than type height,

or slide blocks 8 and 9 respectively between cavity is therefore reduced b the use of a which the cavity for the race tion of the blank matrix'in the form 0 a filler blade molten metal is formed, and t ese type or 57 interposed between the type blocks. This side blocks are referably in the form of .filler blade is conveniently of substantially bars which extend beyond the moldcavity in a thickness corresponding with the point each direction and are ada ted to be sepasize of the material whic the mold is derated a distance which wil determine the signed to produce, and is rovided with width of the mold cavity and consequently overhanging portions 57 a apted for 'cothe point size of the element bein cast. The front typeblock is preferably ormed seated u in two sectlons 9 and 10, for convenience lateral a utment 23 mounted on the upper of manufacture, inasmuch as it has been face of the rear type block 8': said support found desirable to provide at one side of the being'held firmly in position by a matrixmold cavitya channel and exit opening clamp 25 having two' surfaces 25 for cothrough which air and a portion of the moloperation with one edge and the to of the ten metal from themold cavity may escape matrix or filler blade support an an inin the form of a more or less spong mass, clined surface 25" for cooperation with a which, for convenience, may be calle a gate corresponding inclined surface on the lying at one side of the element and adapted matrix abutment 23, whereby .when the to be severed therefrom. matrix clamp is forced down by its clamp- By reference to Fig. 2 it will be seen that ing screw 26 the matrix will be forced downbetween the two sections 9 and 10 there is 4 wardlyand against its abutment where it formed a narrow space which widens out will be held with precision and in such rewithin the type block in the form of a lation to the type block as to prevent an channel which is conveniently of a doveliability of molten metal escaping throng tail or triangular cross section as inthe joints. A squirt preventin shield .40 dicated at 12. The channel 12 and the 'narmay, if desired, be removably he (1 u on the row entrance slot which connects the chanclamp 25 by the washer 4.1 yie dingly nel with the mold cavity are preferably pressed against the shield by the spring 42 slightly tapered or of increasing cross secpositioned between the washer and the head tion toward the exit end so as to prevent of the screw 26-.

fixed accurately thereto and sup-' operation with a filler blade support 59,

on the type blocks, and against a The height of the mold Ill - by suitable stops, not shown.

mums

The mold blade 27 which is mounted to I reciprocate between the side blocks is of a thickness which corresponds to the point size of the material being cast and 1t 1s guided by the side blocks, and by the guide extensions 31, 32, the forward and rearward limits of its movement being determined The mold blade is provided with means whereby its operating member 35 may be readily attached thereto, such means conveniently and preferably consisting of a centrally located circular bearing into which a journal stud 36 on the end of the member 35 is adapted to work. Immediately forward of this cir cular bearing the mold blade is formed with an aperture 28 preferably rectangular for the reception of a lateral vrectangular projection formed on the rear end of the gate pusher 28. The projection of the gate pusher fits loosely within the aperture in the mold blade so that the pusher may without binding adapt itself vertically as may be required by the guide channel 12; the parts are rectangular so that in any position a large bearing surface is provided.

The mold above described substantially corresponds with that in commercial use and generally set forth in the patent previously mentioned. To make such mold practically valuable for producing the lesser point sizes of lead and rule material we have provided the member shown particularly in Figs. 3 and 4 and have proportioned the thickness of this member and the type blocks so that the mold cavity is maintained central over the nozzle opening 20. This member 50 consists, as shown, of a liner block having substantially parallel opposite front and rear faces and located, as shown in Fig. 2, between the forward face of the rear type block 8 and the rear face of the blade 27 and of the produced type metal material operated upon by said blade. The length of this element is substantially the same as the length of the rear type block and it is provided with an extension 51 provided with bolt holes 52 for the accommodation of the usual bolts-53 for securing the type blocks together, and with a water cooling port 54 for connecting thewater cooling channels 54. of the two type blocks: said channels 54 being connected and located in the usual manner except that it has been found preferable to-eliminate the channel in the upper front block 9, conveniently moving it, as shown, in proximity to the front of the lower front block 10.

The member 50 thus forms by a portion of its front surface a side wall ofthe mold cavity upon which wall the side of the mold blade slides during its operation: this surface is accordingly smooth. The rear surface of the element is smooth throughout the greater part of its length and such smooth surface contacts sun 1 with the front surface of the rear type bl ock against which surface the element abuts and is clamped by the bolts 53; but in proximity to the castingcavity, said rear surface of the element is grooved or otherwise formed to retard conduction of heat from the cavity to the rear type block. Only a limited amount of heat can escape in a given time through the grooved area and consequently the heat of the metal cast in molten, filmlike condition in the cavity is retained and prevented from being dissipated through the heat conducting block 8 for a time suflicient to insure the production of a substantially perfect cast filling all portions of the cavity, and of a substantially perfect fusion of this cast to the revious cast in the case of the production y the mold of fused increment material.

The heat retarding portion of the element s 50 comprises, as illustrated, a series of vertical grooves 55 forming ribs 56 between them; the rear faces of. said ribs form the only contacting surfaces of the element 50 with the front face of the rear type block 8 in proximity to the casting cavity. Heat from the cavity which passes through the member 50 at this point has therefore a conducting path of reduced area leading to the type block 8 and is thus retarded in its flow. The dissipating heat flow near the base of the material being cast may not in some cases be desired to be retarded because this part of the material is near the hot nozzle, receiving the last portions of the molten metal being injected, and accordingly may be required to be relatively quickly cooled to prevent its being in part sucked back into the injecting mechanism thus leaving a hollow in the material at the point of injection. To permit of quick cooling at this point and thus to prevent the formation of imperfect casts, the member 50 may be provided with a plane rear surface 60 in prox imity to the bottom of the casting cavity, this surface being produced by stopping the grooves 55 short of the bottom of the mem: her. It will be understood, however, that this heat retarding means formed by that portion of the member 50, the rear surface of which contains the grooves 55 and ribs 56 may be of greater or less extent as may produce the best results. As shown (Fig. 4) the lateral border grooves 55 are longer than the grooves 55 so that the heat from the casting which has entered the member 50 is to a greater extent prevented from escaping by flow longitudinally of the member 50 than if the grooves 55 were of the same length as the grooves 55; and thus the casting cavity wall formed by the element is maintained hotter.

In the modified member 61 shown in Fig. 5 there are provided both vertical and horition of heat from said cavity to saidchan zontal rooves so that in this heatretarding portion of the member the conductin paths are the truncated pyramids 62 an the contacting area is merely the sum of the areas of-the tops of said truncated pyramids. The grooved portion of the modified structure also extends close to the bottom of the member so that there is left substantially no plane area corres onding with the area 60 of the preferred orm shown in Fig. 4. The grooved portion of the modified member is preferably stopped short of the bottom of the member so that there maybe no danger of molten metal entering it during injection from the'nozzle. It will be seen that horizontal as well as vertical ribs, or both, in any proportion, may be provided in order to control the heat dlss'ipation to the required degree and that the provision of a heat retardlng surface of greater or less influence and active area may be accomplished in a variety of wa 's, it being understood of course that the thickness of the member 50 and the depth. of the grooves and the like in its heat retarding portion as well as the area of contact with the rear ty e block 8 are capable of being varied a'nd proportioned so as to produce the proper degree of heat retardation to fit any particular case. More over, the retarding member is removable and replaceable by another, so that the one most suitable for any given condition may be selected.

The operation of the apparatus is as usual, the mold blade being reciprocated from a point in advance of the nozzle open-' ing 20 to a point in rearthereof and the metal being injected through the nozzle 20 at the time the blade is in its retracted position. \Vhen the cooling and freezing of this cast has taken place the blade moves on its forward reciprocation and pushes the cast ahead of it. The type-metal product is clam ed when the blade moves rearwardly y the screw device 18 and is released by said device when the blade moves forwardly.

We claim 1. A mold for strip aater' i elements of printers forms comprising a mold cavity forming structure including type blocks provided with water cooling channels and heat retarding means in proximity to and at the side of said cavity for retarding the dissipation of heat therefrom.

2. A mold for strip material elements of printers forms comprisin a mold cavity forming structure including type blocks provided with water cooling channels and heat retarding means between said cavity and said channels for retarding the conducnels.

3. A mold for strip material elements of to said block of heat from the mold cavity.

4. A mold for strip material elements of printers forms comprising blocks, a portion of a face of one of said blocks forming one wall of the mold cavit a heat retarding member a portion of a ace of which forms another wall of the mold cavity and another face of which is in contact with the other of said blocks, and means between said member and said last-mentioned block and in proximit to the mold cavity for retarding the con notion of heat from said cavity through said member to said lastmentioned block.

5. A mold for strip material elements of printers forms comprising a member, a portion of the forward face of which forms a wall of the mold cavity, a second member, the forward face of whlch is in contact with the rearward face of said first member, the area of contact between said members being reduced in proximity to the mold cavity wall of said first member.

6. A heat retarding member for printers strip material molds comprisinga block of heat conducting material provided with a face for forming a mold cavity wall and a second face opposite to and parallel with said first mentioned face, said second face being grooved to reduce its heat conductivity.

7. A mold for strip material elements of printers forms comprising associated blocks, a heat retarding member contacting with one of said blocks, a portion of the forward face of said member formin one'wall of the mold cavity and the rear face thereof in Y proximity to the mold cavity having a decreased contact area with said block.

'8. A fluid-cooled typographic mold embodying the following instrumentalities, towit; base and side blocks forming the bottom wall and a side wall of the mold cavity, a second side block, a heat retarding member abutting said second side block and forming a side wall ofthe mold cavity, a mold blade slidably mounted between said first side block and said member and a matrix forming the top wall of the mold cavity, a portion of the saidabutting face of the heat retarding member ,being grooved to retard heat conductivity between said member and said second side block.

JOHN SELLERS BANCROF-T. AMOS LESLIE KNIGHT,

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