US2248580A - Method of die casting different articles - Google Patents

Description

July 8, 1941. H. MORIN EIAL METHOD OF DIE CASTING DIFFERENT ARTICLES Filed March 3, 1938 2 Sheets-Sheet 1 W .mm1

W 2 00 E THE N N 4 R W 0 mm n u J4w5 /7 BY M July 8, 1941. H. MORIN ETAL METHOD OF DIE CASTING DIFFERENT ARTICLES Filed March 3, 1938 2 Sheets-Sheet 2 INVE 100/; 440; W74 BY I ATTORN Y n I I W Q la- Patented July 8, 1941 UNETE' STTES PTNT i FICE METHOD F DIE CASTENG DEFFERENT ARTICLES Application March 3, 1938, Serial No. 193,722

2 Claims.

This invention relates to the method of die casting, in a single machine or apparatus a variety of diiferent shaped or characterized castings, each casting being formed from a pair of relatively movable dies, and means being provided for selecting and moving predetermined pairs of dies into casting position with respect to one or more discharge nozzles from which casting material is discharged under pressure into the mold cavities of the dies in forming successive series of castings, governed by the selection of dies throughout said successive series of castings. The invention further relates to a method wherein two casting cylinders are employed whereby said cylinders may be separately brought into registering position with the dies to form castings of the materials of said cylinders which may be different as to color so as to produce differently colored castings as well as castings of different shapes and contours. The novel features of the invention will be best understood from the following description taken together with the accompanying drawings in which certain embodiments of the invention are disclosed and in which the separate parts are designated by suitable reference characters in each of the views, and in which:

Fig. l is a diagrammatic plan and sectional View showing one adaptation of the invention.

2 is a partial section on the line 2--2 of 'Ig.

Fig. 3 is a side detail view of a part of the construction shown in Fig. 1.

Fig. 4 is a view similar to Fig. 2 diagrammatically illustrating another method of carrying out the invention.

Fig. 5 is a partial section on the line 5-5 of Fig. 4, and,

Fig. 6 is a plan and sectional view diagrammatically illustrating a method of actuating the endless die supporting chain unit shown in Fig. 4.

Insofar as the casting machine structure generally speaking is' concerned, the machine may be substantially similar to that shown in our prior application Serial No. 152,942, filed July 10, 1937, modified so as to adapt the same to the methods hereinafter set forth; especially when applied to machines for casting thermoplastics and again more particularly in accordance with the methods taught in our application Serial No. 131,608 filed March 18, 1937. Still further, it will be understood that the principles of the present invention are also applicable to the die casting of other materials including metal in accordance with the teachings of our Patent No. 1,975,966 dated October 9, 1934. For the above reasons, no specific illustration is herein made of such die casting machines or method of handling or treating the casting material as such is clearly known and taught in the patent and applications for patents referred to.

To illustrate one method of carrying the invention into eifect, we have shown in Figs. 1 to 3 inclusive,diagrammatically, one principle or mode of operation which involves the use of a dual cylinder Iii having independent cylinders H and I2 into which separate charges of thermoplastic material, such as cellulose acetate may be introduced through suitable openings indicated in dotted lines at Ila, 12a, forwardly of plungers I3, I31: operating in said cylinders, this in accordance with the teachings of application No. 131,608. Suitable means, for example a heating coil 14 is employed to heat the cylinder unit I!) at the nozzle or discharge end portion thereof. Suitable means will be provided to move the respective cylinders H and I2 into registering position with the mold cavities or impressions of relatively movable dies so as to form castings from the materials of each of said cylinders in any desired successive series. On the other hand, the materials in both cylinders may be of the same color and character and the separate cylinders move into casting position intermittently in order to speed up the production of the machine while giving sufiicient time for the material to be heated in each cylinder.

At 15 and I6 are shown die supporting and operating members which are moved toward and from each other by suitable means as at I! in accordance with the teachings in said prior patent and in application Serial No. 152,942. The inner ends of the members l5 and I6 are recessed as seen at I8 to provide what might be termed forked ends. Mounted in said ends are transverse shafts I9, 19a forming supports for movable die units 20, 20a. in the form of discs or wheels having a. series of projecting and cooperating die parts 2|, 21a, 22, 22a, 23, 23a and 24, 24a. The die parts 24, 24a. are shown in abutting relationship in Figs. 1 and 2 of the drawings.

The die units 28, 29a have circumferential tracks 25, 25a which join the respective pairs of die parts and form surfaces adapted to register with the discharge or nozzle ends of the cylinders l l and 12 when in the neutral position shown in Fig. 1 so as to prevent the discharge of heated casting material therefrom, especially when the die units 26, 290. are shifted to bring other pairs of die parts into abutting relationship similar to the parts 24, 24a.

The shafts [9, Mia protrude outwardly through the members l5, lfia and have beveled gears 26,

26a thereon which are adapted to register with other beveled gears 21, 21a on an elongated shaft 28, suitably supported in the machine forwardly of the members l5 and 6. The gears 21, 21a. are coupled with and movable with the members I5 and IE as seen at 29, 29a, said gears operating in elongated key slots 38, 3&1 in the shaft 28 in this movement. It will thus be seen that as each pair of die parts are moved toward and from each other in successive casting operations, as for example the parts 24, Zea, the gears 21, Zla will move with the dies or the members I5 and I6.

At one end of the shaft 28 is a gear 3! with which a rack 32 operates so as to rotate the units 29, 29a to bring the pair of die parts 2|, 21a to 24, Z ta into registering and casting position. It will be understood that any means may be provided for producing this adjustment or operation of die parts which may be controlled automatically or through the medium of any suitable or known mechanism. In the accompanying drawings, we have shown diagrammatically a manual means for accomplishing this result. This means consists of a hand operated lever 33 pivoted as seen at 34 and having a free coupling as at 35 with the rack 32. The lever 33 is movable relatively to a quadrant or segment 35 having notches 3? adapted to be engaged by a spring actuated pin 38. in different positions of adjustment, which adjustment will be equivalent to the different positions of the die units 20, 26a. At this time it will also be apparent that any number of die parts may be employed on the unit consistent with the size thereof and the size of the castings to be formed. On the other hand, other units may be substituted for those shown for casting other series of different kinds of devices.

In dotted lines in Fig. 2 of the drawings we have shown different shapes of impressions formed between adjacent surfaces of the pairs of die parts when brought together. For example, a double-channelled body or article will be formed between the die parts 24, 2-ia, whereas a cylindrical member will be formed between the parts 23, 23a, a spherical member between the members 22, 22a and a square member between the members 2|, Zia. However, this simply illustrates different shapes and forms which may constitute different shapes or forms of a single article of manufacture; that is to say one article having different symbols thereon. In this connection it is within the spirit of our invention to cast from thermoplastic or other material any kind or class of article or a successive series of articles having the same or difielent characteristics. Furthermore, by utilizing the dual cylinder structure it is possible to produce different castings in different colors selected, as required. It is also preferred that the members and I6 be water-jacketed so that circulating water or other cooling agent may be introduced thereinto through pipes and discharged therefrom through pipes Ml.

It will also appear from a consideration of Fig. 1 of the drawings that the outer surfaces of the adjacent ends of the members it: and I6 are closer to each other than are the inner surfaces of said members to provide clearance for the movement of the cylinders l I and I2 into registering position with each of the impressions of the respective pairs of die parts.

It is also preferred that a suitable core pin or the like M be arranged between and extend This pin will retain the arm I into the impressions of each of the die parts so;- as to provide means for removing the castings from the die parts when separated in the outward movement of the members l5 and I6 and the stripping of the casting therefrom. In this connection it will be understood that the dies are moved toward and from each other in each casting operation of the machine. In this operation one of the cylinders I i or 12 will be moved into registering position with the impression of the dies. When a single cylinder is employed, this cylinder will be moved into the normal sealed position and the injection position in accordance with the teachings in said earlier patent and patent applications.

It will be understood that any number of suc cessive castings may be formed from each pair of die parts when in the casting position, but whenever desired the members or units 20, 2% may be rotated to bring any other, or desired, pair of die parts into the casting position. It will thus be also apparent that successive castings may be formed from independent pairs of die parts which would mean that a constant change of die parts will take place at each successive casting operation of the machine. The latter arrangement will depend entirely upon the particular type and kind of machine employed and the nature of the products or castings produced thereby.

In Figs. 4, 5 and 6 we have illustrated diagrammatically another adaptation of the method which differentiates primarily from the structure diagrammatically illustrated in Figs. 1 to 3 inclusive in the provision of two endless chain units 42, Ma. In the construction shown, these units consist of ten pairs of die parts 43, 43a, the parts 43 constituting the unit i2 and the parts 43a constituting the unit 42a. The parts of the first unit are joined by pairs of links 44 whereas theparts of the other unit are joined by pairs of links E la. Side surfaces of the parts 43, 43a at upper and lower ends thereof have recesses 45 of triangular shape in which the ends of the links 4 3, Ma are mounted so as to bring outer surfaces of the links flush with outer surfaces of the die parts d3, 43a; thus providing a substantially endless track which will register with the nozzle discharges 35, Mia of two cylinders 67, 37a similar to the cylinders H and I2 of Fig. 1 of the drawings. Thus it will be seen that in the neutral position of the cylinders as shown in Fig. 5, the nozzle discharges will be sealed as the units 52, 52a are rotated to bring the different pairs of die parts '13, 430. into casting position between relatively movable die operating members 8, 58a operated substantially in the same manner as the members l5 and [5.

It will be understood that each pair of die parts 23, @317. will form a different casting between adjacent abutting surfaces thereof, depending entirely upon the particular use of the invention. For this reason no particular form of impression is shown in the different pairs of castings, as the particular form or contour of the product is of no consequence, with the exception that the impression will naturally have to be. of such contour as to permit the removal of the resulting casting therefrom.

Each die part of the separate die parts is provided on one surface thereof with a substantially V-shaped socket 49 opening into a. channel 53 so as to receive the teeth 5| of drive sprockets 52 mounted on drive shafts 53, as well as similar teeth SE a of other sprockets 52a on idler shafts 53a, so that in the rotation of the drive shafts 53, the chain units 42, 42a may be collectively operated. to bring another pair of die parts 43, 43a into registering position between the die operating members 48, 48a.

In Fig. 6 of the drawings we have diagrammatically illustrated at 54 a part of a shaft which may be operated. and controlled in any desired manner to produce the aforesaid adjustment and movement of the units 42, 42a. The shaft 54 has a beveled gear 55 registering with another beveled ear 58 on one of the shafts 53. The two shafts are geared together by gears 51, 58 as indicated in Fig. 6 of the drawings. In the different positions of adjustment of the units 42, 420. it is preferred that these units be operated in the direction of the arrows at in Fig. 4, so that dovetailed outer ends 59 of the parts 43, 43a may be moved into the upper beveled ends of corresponding channels 60 formed upon the inner surfaces of the members 48, 48a to receive said dovetailed ends 59 to key the die parts 43, 43a with the members 48, 48a. to permit movement of the die parts toward and from each other.

A suitable core pin 6| is mounted in a support 62, note Fig. 5, and is operated through a. lever 63 which may be pivoted to one of the members, the member 48 as shown. The lever 63 is actuated through a link or connection as at 64 coupled with a cam or any other operating means of the machine so as to move the core pin into position between the dies and into a mold cavity, for example the cavity 65, shown in Fig. of the drawings, so that the castings will be formed on the pin and the pin utilized as a means for ejecting the casting from the separate die parts when separated, and also in moving the casting to a position to engage the support 62 to be stripped from the pin. The pin 6| also serves to accurately aline the die parts 43, 43a; one with the other to maintain the desired registration of the mold cavity 65 or the gate or admission passage 6511 leading thereto, with the nozzles 45, 46a of the casting cylinders 41, 41a.

The operation of the method in accordance with the teachings in Figs. 4 to 6 inclusive will be substantially the same as that in Figs. 1 to 3 inclusive aside from the particular manner of actuat ing the units 42, 4211. In this connection it will be understood that from time to time different pairs of die parts may be substituted for removed pairs of die parts in the chain units by providing suitable means for attaching and detaching the links therewith. However, it is also possible to remove the units 42, 42a and replace or substitute other units which will perform a totally different series of castings.

It will of course be understood that sufilcient flexibility will be provided in the chain units 42, 42a. to permit relative movement of the die parts whicli are in coupled position with the members 48, 48a. It understood that these members will separate sufficiently to permit the withdrawal of the casting formed between adjacent surfaces thereof. It will also be apparent in this connection that the units may be made up in any desired series of die parts depending entirely upon the length of the chain and the size of the pairs of die parts employed thereon. In the accompanying drawings, the sizes are very much enlarged for the purpose of clear illustration, but in actual fact each die part may be relatively small in size and a number of such parts may be joined in the form of an endless conveyor or chain, the coupling of which may be in the form of links, or in any other practical manner.

With the construction shown in Figs. 4, 5 and 6 it will be apparent that a single means or cylinder may be provided for discharging the casting material employed, and castings may be made from metal or thermoplastic materials as desired. The invention consists primarily in the use of a multiplicity of dies or molds which may be selectively brought into registering position with a suitable injection means for injecting casting material under pressure into the impression or mold cavity in any desired or predetermined arrangement of successive castings. It will appear that the selection may be automatically or manually controlled and regulated, and the number of different pairs of dies employed as well as the contour of the impressions therein will govern the different and distinct modes of carrying our method into effect.

Having fully described our invention, what we claim as new and desire to secure by Letters Patent is:

1. The method of selecting and operating different dies in forming a plurality of die castings of different contour, which comprises arranging pairs of die elements in two units with one die element of each pair in each unit and. each unit comprising a plurality of interconnected die elements, simultaneously operating both units to move one die element of each unit to a casting station in providing a selected die, holding each pair of die elements stationary and in firm engagement with each other when at said casting station while pressure discharging heated casting material into the cavity of the die in forming one or a series of castings of the object defined by the cavity of said selected pair of die elements, opening and closing the die elements at said station after the formation of each casting to remove the casting, moving the first selected pair of die elements from the casting station. and simultaneously moving a second selected pair of die elements to the casting station.

2. The method of selecting and operating different dies in forming a plurality of die castings of different contour, which comprises arranging pairs of die elements in two units with one die element of each pair in each unit and each unit comprising a plurality of interconnected die elements, simultaneously operating both units to move one die element of each unit to a casting station in providing a selected die, holding each pair of die elements stationary and in firm engagement with each other when at said casting station, arranging two ejector nozzles for the pressure discharge of different casting materials at said station, moving said nozzles selectively and individually into position to communicate with the cavity of the die supported at said station, pressure discharging the different materials selectively from the different nozzles in forming a series of castings from the pair of die elements supported at the casting station of the material discharged from said nozzle, and opening and closing the die elements at said casting station after the formation of each casting to remove each casting.

LOUIS H. MORIN. DAVIS MARINSKY.

Images