US1814820A - Extruding die for forming ophthalmic mountings - Google Patents

Description

July 14, 1931. w R. A. BQSWELL EXTRUDING DIE FOR FORMING OPHTHALMIC MOUNTINGS Filed 1925 Patented July 14, 1931 units.

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is ornrnsnrrrcl Mounrrnes Application fil'edAugust 7,1925. Serial 110.48,?02.

ning mass, and then rolled intosheets tobe again subjected to astamping process.

More recent processes involve the use of a die for extruding a fibrous material through an opening in thed'ie, the opening having a contour contorming to the configuration of an ophthalmic mounting-, there being tongues supportedf ithin a chamber or casing and centered Within eye portions of the opening to form the eyes of the ophthalmic mounting, the tongues being separate from the die, in which case the die cannot beused inv connection With any form of extruding machine. l n'such a method and machine the material When extruded is in a bode, which necessitates subsequent cutting in order to form or pr duce the actual. mounting. This method is not a continuous operation, but an interrupted operation, hence a machine of this kind- With the resulting process, is impractical, it being difiicult to remove the body from the die for the purpose of subsequent cutting to term the. mountings. Furthermore, such construction of dies cannot be applied to any type of extruding apparatus, there being no Way of mounting the tongues, which makes this type of die undesirable.

Another type of die, While being in one piece, consists of tongues spaced Within the tubes of the die for producing the eyes of the mountings, but in this construction it is difiicult to remove the body (from which the mountings are out) after it is formed, such mounting being very apt to be deformed; or distorted during the process of removal-,- and this disadvantage, coupled with. the fact that this construction is not applicable to any type of machine, renders such the impractical; and undesirable. In both of these. constructions the fibrous material is formed into tubular bodies, from which the mountings are subsequently cut,

thus making both methods long drawn out processes,

WVith the above facts in View it is the purpose 0t thepresent invention to shorten the process of making the mountings, accomplishing it quicker and with greater ease, and Without distorting or deforming the fiber body as the mountings are belng cut.

Another purpose is to provide a die of this kind which is applicableto any type of machine, more especiallythe construc 'tionofmachine as set forth, illustrated, and

claimed in the co-pendin application, filed 7th day of August, 1925-, Serial No. 48,701.

Another purpose is to provide a; die which is not only in one piece, and from which there is no necessity oi removing the body for the purpose of cutting the mountings therefrom b'ut'is ca abie 0t vermittin the mountings to be out instantly as the material extrudes through the opening in the die.

Still another purpose is to provide a die with cuttingmeans carried thereby, so that a,

such means can be operated in any manner, preferably by a mechanism as disclosed in the above identified co-pending, app1ica tion, the mountings beingcut as the fibrous material extrudes through the opening in is the die. I I V A turther purposeis to provide means for supporting cores in the eye portions of the opening in the die, said supporting means in the 'dieand the cores all being in one v piece, said supportingmeans being adjacent the extruding end of a cylinder, so as not to interfere with the formation as it e:;- trudes through the opening in the die. in other Words, the material as it extrudes Works around the supporting means, and then discharges from the opposite face in a shape conforming to the contour of an ophthalmic mounting, and as. the material extrudes sufficiently it is cut off by the cutting means, so, that each mounting may be subsequently finished and polished suitable to receive the lenses.

A still further purpose is to provide means for cooling the die in order to, stiffen.

or season the material as it is extruded, but not enough to retard the passage of the material through the opening in the die, the material being previously heated to render the same more plastic, in order that it may work around the supports for the cores.

A still further purpose is the provision of means for supporting and fastening the die to the end of the extruding cylinder.

Moreover, it is the purpose to provide a guard means to hold the knife or severing member in close contact with the face of the die, as it severs the ophthalmic mounting.

It is to be understood that the particulars ierein given are in no way limitive and that, while still keeping within the scope of the invention, any desired modifications of details and desired proportions may be made in the apparatus accordin to the circumstances.

The invention comprises further features and combinations of parts, to be hereinafter set forth, shown in the drawings and claimed.

In the drawings Figure 1 is a sectional View through a portion of one end of a cylinder of an extruding machine (which is similar in design to that disclosed in the co-pending application above identified), showing the improved die as applied. 1

Figure 2 is a perspective view of more clearly showing the outer face and illustrating the cutting device ried thereby.

Figure 3 is a perspective view of the die showing the inner face of the die, and also showing a part of the cutting device.

Figure 4- is a detailed perspective view of an ophthalmic mounting, such as may be extruded through the die.

Figure 5 is a detailed view in section on line 55 of Figure 2, showing that the hollow of the die is formed adjacent that portion of the wall of the die which forms the bridge of the ophthalmic mounting.

the die thereof as car- Referring to the drawings, 1 designatesa base of a portion of an extruding machine, such as is disclosed in the above identified co-pending application, and 2 is a cylinder mounted upon the base in a Well known manner, the cylinder adapted to receive a feed screw 3 for feeding the plastic fibrous material, such as cellulose, or the like, through the opening 4 formed in the die 5. The feed screw has one of its pintles 6 journaled in a bearing of a web or spider 7 constructed on the interior of the cylinder. An exterior heating coil or element 8 is carried by the cylinder for keeping the plastic material in a sufiiciently plastic state as to cause it to readily feed through the cylinder.

The die has radial lugs 9 between which bolts 10 are pivoted as at 11, the bolts designed for engagement in bifurcations 12 formed in lugs 13 which project radially from the cylinder at one end. By moving the bolts 10 in the bifurcations and tightening up on the nuts 14, the die 5 may be held closely against the end of the cylinder.

The opening 4 in the die is of a contour conforming to the configuration of an ophthalmic mounting, and the circular portions 15 for forming the eyes of a mounting contain cores 16, which are concentric with the circular portions 15, to produce the openings in the eyes of a mounting. It will be noted that the cores are integral with the die, rigidly and firmly supported by ribs or arms 17, which are radial of the circular portions 15 of the opening 4. By arranging the arms or ribs 17 on the die adjacent its face, which contacts with the end of the cylinder, it enables the plastic composition to work around them so that the composition may feed out in a solid mass, of which its cross sectional contour conforms to the shape of an ophthalmic mounting. As this solid mass is extruded the ophthalmic mountings may be cut or severed therefrom instantly upon its extrusion from the die.

A cutting knife 18 operates immediately adjacent the face of the die remote from vided with opposite cutting edges 19. The

knife is mounted pivotally upon a headed bushing 20, which is secured to the die by means of a bolt or the like 21. In this way the knife has freedom of movement. As previously stated, the knife works closely in contact with the outer face of the die, and to insure this close contact an arcuate guard 22 is provided, which is concentric with the die and has arms 23 which overly and are secured at 24 to the cylindrical periphery of the die; The knife works between the guard and the face of the die, and by means of such guard the knife is held in close contact with the face of the die. The short end of the knife, as is shown in Figure 1, has connected to it a pitman or link 25, which is in turn pivotally connected to a disk 26 carried by a shaft 27. The shaft, disk, and the link, 27, 26 and 25, correspond to similar elements in the copending above identified application, and are only shown herein for the purpose of illustrating how the knife may be actuated.

As previously stated, the fibrous material is heated for the purpose of insuring a more plastic state as the material extrudes, and to avoid extreme distortion or deformity of the mountings as they are cut, the die is constructed hollow, thereby providing a chamber 28 for the reception of a cooling fluid, for chilling the composition, causing it to stiffen and season sufiicient to enable the mountings to be cut therefrom the composition discharges from thecpeningt. This stiffening and, seasoning: of the compor sition' is not to be such as toretard the extrusion of the material. This improved die is to. be made up as an article of manufacture tobe sold for use on extruding; machinesof various types, especially those for extruding ophthalmic mountings, which are of the shape asshown in Figure 4 of" the drawings. The cooling; fluid; is allowed to enter the chamber 28 through a pipe-29 and discharge through another pipe 30, thereby enabling the fluid to circulate through the hollow of the die and cause thematerial to relatively stiffen and season.

The invention havingbeen set forth what is claimed is:

, 1. A die for extruding ophthalmic mountings, comprising a body with an opening, whose contour adjacent the outlet portion of the opening conforms to the configuration of an ophthalmic mounting, said die having cores fixedly supported in thecircular portions of the opening for forming the eyes of a mounting, the die being hollow around the walls of said circular portions, said hollow extending between. the circular portions, whereby a cooling fluid may temper the bridgev of the mounting.

2. A die for extruding ophthalmic mount,- ings, comprising a body with an opening, whose contour conforms-to the configuration of an ophthalmicmounting,said die having cores supported in the circular portions of the opening for forming the eyes of a mounting, a cutting knife fulcrumed upon the outer faceof the die to act in close. contact with the face for serving the mountings as the material extrudes through the opening.

3. A die for extruding ophthalmic mountings, comprising a body with an opening, whose contour conforms to the configuration of an ophthalmic mounting, said die having cores integrally supported in the circular portions of the opening for forming the eyes of a mounting, a cutting knife fulcrumed upon the outer face of the die to act in close contact with the face for severing the mountings as the material extrudes through the opening, and means for supporting the cores in the circular portions of the opening adjacent that face of the die which engages with an extruding cylinder, so that the composition may work around said means and allow the composition to feed out in a solid mass of which its cross section resembles the shape of an ophthalmic mounting.

4-. As an article of manufacture a die, having an opening, whose contour conforms to the shape of an ophthalmic mounting, the circular portions of the opening having cores concentrically spaced. therein, with ribs adjacent the inner face of the die to integrall-y supportthecores,the diebeing hollow around the walls of said circular portions, said hollow extending between the circular portions, whereby a; cooling fluid may temperthe bridge of the mounting.

' 5. A diefor extruding ophthalmic mount.- ings, comprising a body with; an opening, whose contour adjacent the outlet portion of the opening COHfOIIDSd'QO thQ configuration of an ophthalmic mounting, said die having cores fixedly supported in. the circular portions (if-the opening for forming the eyes of a, mounting, the; the being hollow thereby forming a chamber therein for the reception upon the outer face of: the die to set in' close contact with the face for severingthe mountings as the material extrudes through the opening, and. means'in. the circular portions of the opening adjacent the face of the die which engages with. an extruding; cylinder, so that the, composition may work around, said means and allow the composition to feed out in a solid mass of' which its cross section resembles the shape of an ophthalmic mounting, the die being iollow thereby forming a chamber therein for the reception of a, cooling fluid, to temper the composition as it is extruded.

7'. As an article of manufacture, a die having an opening, whose contour conforms to the shape of an ophthalmic mounting, the circular portions of the opening having cores concentrically spaced therein, with ribs adjacent the inner face ofthe die to fixedly support the cores, and. a. cutting element operatively mounted on. the outer face of the die for severing .the ophthalmic mountings as the composition extrudes through the opening.

8. As an article of manufacture, a die having an opening, whose contour conforms to the shape of an ophthalmic mounting, the

circular portions of the opening having cores concentrically spaced therein, with ribs adjacent the Inner face of the die to fixedly support the cores, and a cutting element operatively mounted on the outer face of the die forsevering the ophthalmic mountings as the composition extrud'es through the opening, and aguard to hold the knife in close contact with the outer face of the die.

9. As an article of manufacture, a die comprising a bod-y with an opening, whose cone tour conforms to the shape of an ophthalmic mounting, cores concentrically spaced with in'the circular portions of said opening, said opening having an unobstructed discharge end, whereby a composition material may extrude therefrom to intermittently form ophthalmic mountings, and means for cutting the mountings as they extrude from the discharge end, and a circular guard adjacent the outer face of the die to hold the cutting means close to the die.

10. In combination with an ophthalmic blank extruding die in an integral one-piece body, with a single opening having the shape of an ophthalmic mounting, the opening having a composition receiving mouth enlarged adjacent one face of the die and a composition discharge mouth reduced adjacent the opposite face of the die, whereby a steady uninterrupted stream of composition may extrude therethrough, and cutting means operating against the outer face of the die and movable across the discharge extruding mouth, whereby the composition, as it extrudes from the discharge mouth, may be cut into ophthalmic blanks, and means to retain the cutting means close to said outer face.

11. A die for extruding ophthalmic mountings, comprising a body with an opening conforming to the contour of an ophthalmic mounting, the die being hollow, the hollow of the body extending substantially entirely around the circular portions of the ophthalmic opening and between the circular portions whereby a cooling fluid circulating in the hollow may temper the bridge of the ophthalmic mounting.

12. A die for extrudin ophthalmic mountings, comprising a hOllOW body with an opening formed through the body, said opening having a contour conforming to the configuration of an ophthalmic mounting, the circular portions of the ophthalmic opening and the bridge portion thereof being enlarged adjacent the inner face of the die,

the circular portions of the ophthalmic opening and its bridge portion adjacent the outer face of the die being restricted'whereby a plastic composition may feed gradually through the ophthalmic opening, and cores fixedly supported in the circular portions of the ophthalmic opening, said cores being tapered from their outer ends toward their inner ends, the hollow extending around the walls of the circular portions of the ophthalmic opening and between the circular portions, whereby a cooling fluid may temper the bridge of the ophthalmic mounting as the material extrudes through the opening.

13. A die for extruding an ophthalmic blank, consisting of an integral one-piece body with an ophthalmic blank forming opening therein and being hollow, with the hollow conforming to the wall of the oph- 'ings connected by an arcuate opening, the

walls of said opening being convergent tofor extruding ophthalmic ward the discharge end of the die, cores disposed concentrically to the circular openings, said cores having a depth equal to the depth of said openings, and webs connecting the cores to the walls of said openings at points spaced from the ends of the arcuate opening, said webs being disposed at the inner ends of the cores and being of less length than the cores.

15. An ophthalmic blank extruding die in an integral one piece body with an uninterrupted extruding passage whose contour conforms to the shape of an ophthalmic blank, said body being hollowed out, said hollow being formed around the eye and bridge portions of the opening, to permit of the circulation of a cooling fluid.

16. An ophthalmic blank extruding die in an integral one piece body with an ophthalmic blank extruding opening therein, through which from one face of the die a steady uninterrupted stream of plastic cellulose composition may be extruded, whereby the composition may extrude from the opposite face of the die, said die being hollow around the bridge and eye portions of the ophthalmic blank extruding opening, to permit of circulation of a cooling fluid therein.

In witness whereof, the in'ventors signa ture is hereunto affixed.

ROBERT A. BOSWELL.

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