US2775802A - Casting machine - Google Patents

Description

Jan. 1, 1957 Filed June 17, 1953 O. H. BOUGHTON CASTING MACHINE 4 Sheets-Sheet l CASTING MACHINE 4 Sheets-Sheet 2 Filed June 17, 1953 Jan. 1,1957 Q H, B UGHTON 2,775,802

CASTING MACHINE 4 Sheets-Sheet s Fild June 17, 1953 Y Z P. f N M MW 7 0 i E w 4 #5 m United States Patent CASTING MACHINE Owen H. Boughton, Chicago Heights, 11]., assignor to Gould-National Batteries, Inc., St. Paul, Minn., a corporation of Delaware Application June 17, 1953, Serial No. 362,245

3 Claims. (Cl. 22-.76)

This invention relates to a metal casting machine of the automatic type whereby a series of molds are moved along a determined path and successively filled with molten metal, cooled to solidify the metal in the mold cavities and then emptied by ejecting mechanism whereby the castings are removed from the molds and collected in suitable containers.

An object of my invention is to provide a simple, rugged machine of the class described which is adapted to produce castings of various sizes and shapes and of uniformly good quality rapidly and continuously.

A further object is to provide in a machine of the class described, an endless conveyor which is arranged to carry a multiplicity of molds in such position as to make the individual mold cavities accessible for inspection and treatment during their travel along a determined path.

A particular object is to provide such a casting machine with a novel mold conveyor comprising a pair of endless chains between which a multiplicity of molds are carried with their metal receiving cavities exposed for treatment at selected positions along their path of travel, the conveyor having horizontally extending upper and lower reaches and the machine being provided with mechanism for filling the molds with molten metal positioned above the upper conveyor reach and mechanism for ejecting the castings from the molds positioned above the lower horizontal reach of the conveyor.

My invention also includes certain other novel features of construction which will be more fully pointed out in the following specification and claims.

In the accompanying drawings which illustrate, by way of example and not for the purpose of limitation, a preferred embodiment of my invention:

Figure 1 is a top plan view showing my improved casting machine;

Fig. 2 is a front elevational view of the same;

Fig. 3 is a side elevational view of the machine as seen from the right side of Figs. 1 and 2';

Fig. 4 is a fragmentary vertical sectional view taken approximately on the line 4--4 of Fig. 1;

Fig. 5 is a vertical sectional view taken approximately on the line 5-5 of Fig. 4;

Fig. 6 is a fragmentary end view showing in detail the cam and lever for actuating the molten metal control valve;

Fig. 7 is a side elevational view of the same cam and lever;

Fig. 8 is a part side elevational and part longitudinal sectional view showing one of the molds;

Fig. 9 is a plan view of one of the molds, showing details, and

Fig. 10 is a fragmentary sectional view showing one of the mold closing pressure bars.

Molds and conveyor Referring to the drawings, mold blocks indicated generally by the numeral 10 are formed with cavities 11 to 7 Patented Jan. 1, 1957 cavities shown are adapted to form connector bars for storage batteries. These cavities are normally open at the outer faces of the mold blocks and a multiplicity of the blocks are mounted on a conveyor comprising a pair of endless chains 12 each of which is trained on three idler sprocket wheels 13 and a power-driven sprocket wheel 14. The sprocket wheel 14 is fixed on a driving shaft 15 and the latter is turned intermittently through the operation of a Geneva gear wheel 16 which is also fixed on the shaft 15.

Stationary guides for the conveyor chains and mold blocks carried thereby include a pair of horizontally extending angle bars 17 extending along the upper portion of the machine, similar horizontally extending bars 18 extending along the lower portion of the machine, as best shown in Figs. 4 and 5, and vertical guides 19 and 20 for the downward travel of the conveyor and molds at the right side of the machine as shown in Figs. 2 and 4. Each mold block is supported on horizontally extending bars 21 and 22 which project from the ends of the block to slidably engage the guides. During the downward travel of the mold blocks the bars 21 slidably engage the inner face of the guide 29 and the bars 22 slidably engage the outer face of the guide 19 to retain the mold blocks in the tilted positions indicated in Figs. 2 and 4. Projecting from the ends of the bars 21 are studs 23 which fit in bearings carried by the chains 12 to pivotally connect the molds to the chains at the leading or forward sides of the molds.

Mold filling mechanism My improved conveyor is arranged to move the several molds successively beneath a trough, indicated generally by the numeral 24, which is positioned above the upper horizontal reach of the conveyor. An outlet port in the bottom of the trough delivers the molten metal to the several cavities in the mold blocks and the flow of metal to the molds is under control of a valve 25. From a suitable source such as a lead pot and pump of conventional design the molten metal is supplied to the trough through a pipe 26 (Figs. 1 and 3) and the excess metal is continuously returned to the source from the trough 24 at its open end 25a (Fig. 3).

To actuate the valve 25 in timed relation to the movement of the conveyor, I provide linkage including rocker arms 27 and 28 fixed on a supporting shaft 29 and a rod 30 which depends from the free end of the arm 28 and is operatively connected to a cam actuated lever 31. As best shown in Figs. 4 and 5, a lug 32, integral with the lever 31, is perforated to slidably receive the rod 30 and this rod projects below the lug and is fitted with a coiled spring 33 and head 34 for confining the spring on the rod. A collar 35 is adjustably secured to the rod 31) above the lug 32 to transmit upward movement to the rod from the lever 31. Downward oscillating movement of the lever 31 is transmitted to the rod 30 through the spring 33. Pivotally supporting the lever 31 at one end is a bolt 36 projecting from a supporting bracket 36:: and a roller 37 carried by the other end of the lever is arranged to be actuated by a cam 38 fixed on a shaft 39, as best shown in Figs. 6 and 7. The roller 37 is held in contact with the cam by a spring 40 which is anchored at one end on a fixed frame member 41 and connected at its lower end to the lever 31. The cam 33 is arranged to actuate the lever 31 downward and to hold the valve 25 open during approximately three-quarters of each complete revolution of the shaft 39 and to cause the valve to be closed for approximately the remaining one-quarter of each revolution. During the period when the valve 25 is closed the conveyor is operated to place the succeeding mold in position to be filled from the trough 24.

E jecting mechanism Each of the mold blocks is provided with a plurality of ejector pins 42 which are movable in guide perforations extending from the back surface to the cavity in each mold block. As best shown in Figs. 8 and 9, the pins 42 for each mold are secured to a common actuating plate 43 and the latter is movable to and from the back face of the block and normally held in spaced relation to the block by a pair of springs 44. Confining and guiding members 45 limit movement of the plate 43.

Supported above the path of travel of the molds along the lower horizontal reach of the conveyor chains 12 is a shoe 46 disposed to be actuated downward when a casting is to be ejected from the mold. This shoe is held in contact with the lower face of a vertically movable block 47 which is slidable in a housing 48 and the latter is rigidly supported on parallel frame members 49 extending across the machine. Springs 50 (Fig. 4) are confined in recesses in the block 47 and are arranged to engage the lower surface of a follower plate 51 and to resiliently transmit motion from this plate to the block 47. Springs 52 support the shoe 46 in engagement with the bottom surface of the block 47 and perform the function of withdrawing the ejector mechanism from the upper surface of the plate 43 after each operation.

A roller 53 is arranged to engage the upper surface of the plate 51 and is mounted on an arm 54 having a pivotal support 55 on members 49a. An arm 56 is rigidly connected to the arm 54 and extends obliquely upward, being provided with a roller 57 on its upper end for engagement with a cam. The arm 56 comprises two relatively adjustable members which are fastened together by set screws 58 engaging one of the members in elongated slots so that the effective length of the arm 56 may be adjusted. To actuate the upper end portion of the arm 56 obliquely downward, a finger 59 is fixed on the shaft 39 and projects therefrom to strike the roller 57 and thereby actuate the ejecting mechanism once during each revolution of the shaft 39.

Mold closure device A machined bottom face 60 is formed on the trough 24 for sliding contact with the flat upper faces of the mold blocks 10. Each mold block as it passes beneath the face 60 of the trough is pressed upward resiliently by a pair of pressure bars 61 each of which is supported on a pair of vertical plungers 62. These plungers are movable in cylinders 63 severally containing compression springs 64 (Fig. 10) engaging the lower ends of the plungers 4. The cylinders 63 have threaded connections at their upper ends with the frame member 41.

Driving mechanism Fixed on one end of the shaft 39 is a sprocket wheel 65 which is driven by suitable connections with a powerdriven shaft 66. This shaft projects from speed reducing mechanism in a housing 67 and the latter is operatively connected by pulleys and a belt 68 to an electric motor 69. A stub shaft 70 (Fig. 2) is ecccntrieally mounted on the sprocket wheel 65 to project from the inner face thereof and a small roller 71 is carried by the stub shaft for engagement with the Geneva gear wheel 16. This wheel is formed with radially extending cam grooves 72 adapted to receive the roller 71. There are four of these grooves arranged to coact with the roller '7]. in turning the conveyor drive shaft 15 one-quarter revolution for each revolution of the shaft 39.

Casting take-ojj mechanism A circular take-oft table indicated generally by the numeral 73 is fixed on a vertically extending central shaft '74 and carries a number of segment shaped removable receptacles 75 adapted to receive the castings as they are ejected from the molds. The number of the receptacles is equal to the number of molds so that the castings from each mold are collected in one receptacle and separated from those ejected from the other molds on the take-off table. As indicated in broken lines in Fig. 3, the compartments 75 are large enough so that each is adapted to contain a large number of the castings. Fixed on the lower end portion of the vertical shaft 74 is a worm wheel 77 (Fig. 2) arranged to be driven by a worm 78 fixed on a horizontally extending shaft 79. A sprocket wheel on the outer end of the shaft 79 is arranged to be driven by a chain 80 which is driven, in turn, by a sprocket wheel fixed on an end of the shaft 39. The rate of turning of the table 73 relative to the rate of travel of the mold blocks along the conveyor is such as to cause the successive receptacles 75 on the take-off table to be positioned beneath the several mold blocks as they reach a predetermined position beneath the ejector plate 46.

The mechanism hereinbefore described is supported on a suitable frame comprising a base indicated generally by the numeral 81 and upright members 82 rigidly connected together in a suitable rectangular structure by horizontal members 85 and 86 and also by the horizontal mold guides 17 and 18. An auxiliary frame projects to the front and laterally of the main frame to support the motor 69, this auxiliary frame being indicated generally by the numeral 87. The motor is so supported on the auxiliary frame as to permit adjustment of the tension of the belt 68, the adjusting mechanism including a hand wheel 88 which may be operated to move the motor along guide rods 89, as best shown in Figs. 1, 2 and 3.

Summary 0 operation In preparation for use, selected mold blocks 10 are attached to the chains 12 at the left side of the machine as seen in Figs. 1 and 4. This may be accomplished merely by separating the chains and inserting the studs 23 formed on the bars 21 in the sockets carried by the chains at suitably spaced intervals. In this manner molds designed to form castings of a variety of sizes and shapes may be mounted on the chains for simultaneous use.

Ordinarily, preparation for the molding operation requires treatment of the surfaces defining the mold cavities 11 by coating them with suitable material adapted to facilitate the separation of the castings from the molds. Suitable coating materials for this purpose are well known in the art and are usually applied in the form of a spray as the mold blocks are moved by the conveyor downwardly at the right side of the machine and upwardly at the left side where the mold cavities are exposed and readily accessible for treatment.

During the molding operation molten metal at the proper temperature is fed through the pipe 26 to the trough 24 and is returned from this trough to the source of supply, thereby maintaining the lower portion of the valve 25 submerged in molten metal. The motor 69 is operated to actuate the conveyor chains 12 with the step by step movement imparted to them by the roller '71 carried by the driven sprocket wheel 65' and the Geneva gear wheel 16 which is fixed on the shaft 15 carrying the driving sprocket wheels 14 for the chains 12. The mold blocks are thereby moved successively beneath the surface 60 of the trough 24 to receive molten metal when the valve 25 is opened through its connection with the cam 38 fixed on the shaft 39. During the filling operation the mold block beneath the filling trough is pressed upward to seal the cavity at the sides thereof by the operation of the pressure bars 61 engaging the mold carrier bars 21 and 22. This filling operation is repeated with successive molds. They are thereafter moved by the conveyor to the right as seen in Fig. 4 and then downward and to the left along the guide bars 18. During this portion of mold travel the castings solidify and cool in the mold cavities. The full molds are then carried, one after another, beneath the ejector shoe 46 and each mold dwells beneath this shoe while the ejector finger 59 is caused to strike the roller 57 carried by the arm 56 to thereby actuate the arm 54 carrying the roller 53 downward against the plate 51. This plate is thereby struck downward against the bias of the springs 50 which actuate the block 47 together with the shoe 46 downward. The latter strikes the plate 43 of the mold block beneath, causing the ejector pins 42 to strike the casting in the mold cavity thereby ejecting the casting into one of the compartments 75 of the take-off table. Should the casting in the mold cavity resist the pressure exerted through the springs 50, continued downward movement of the roller 53 will cause the plate 51 to strike the upper face of the block 47 and thereby positively force the ejector pins into the mold cavity and insure the emptying of the mold.

After each mold block has been emptied, the conveyor moves it, step by step, While the block cools and the cavity is exposed at the left side of the machine for repair or coating treatment. The take-01f table 73 is rotated in timed relation to the operation of the mold carrier and there is a separate compartment on the table to receive the castings from each of the several molds. Thus the castings from each mold are separated from those of each of the other molds in the take-off containers. This facilitates the sorting of the castings Where castings of different sizes or shapes are being molded and it also facilitates the location and repair of defects in particular molds. My improved machine operates rapidly and efliciently and is unusually durable and reliable in operation.

Having described my invention, what I claim as new and desire to protect by Letters Patent is:

1. In a metal casting machine, a pair of endless conveyor members movable in unison and in spaced parallel vertical planes, said members having elongated substantially horizontally disposed upper and lower reaches, power actuated means for imparting to said conveyor members step by step movement along a determined, endless path, a multiplicity of mold blocks carried by said conveyor members with the blocks spaced apart one from another longitudinally of said members and also spaced laterally from said members, each of said mold blocks being formed with a mold cavity, molten metal supply means comprising a trough disposed at a fixed elevation to slidably engage said mold blocks during their movement along said upper reach of the conveyor members and disposed to deliver molten metal to the several cavities in said mold blocks, valve means including a closure member controlling the flow of metal to the several mold blocks, said metal supply means including means for submerging said closure member in a shallow pool of continuously flowing hot metal whereby to maintain the temperature of said closure member substantially above the melting temperature of the metal, ejecting mechanism operative to eject castings from the molds at a point spaced along said conveyor members from said metal supply means, and means for actuating valve means and ejecting mechanism in timed relation to the movement of said conveyor members along said path whereby one of said cavities in a mold block is filled with molten metal while a casting is ejected from the cavity of another mold block.

2. In a metal casting machine, a pair of endless conveyor members movable in unison and in spaced parallel vertical planes, power actuated means for imparting to said conveyor members step by step movement along a determined endless path, a multiplicity of mold blocks carried by said conveyor members with the blocks spaced apart one from another longitudinally of said members and also spaced laterally therefrom, each of said mold blocks being formed with a mold cavity extending to the outer face of the block, said conveyor members having upper and lower substantially horizontal, elongated reaches connected by substantially vertically elongated reaches said mold cavities being exposed for inspection and treatment when the blocks are positioned along said substantially vertically elongated reaches of said conveyor members, molten metal supply means disposed to deliver molten metal to the several cavities in said mold blocks, valve means controlling the flow of metal to the several mold blocks, ejecting mechanism operative to eject castings from the molds at a point spaced along said conveyor members from said metal supply means, and means for actuating said valve means and ejecting mechanism during intervals between steps in the movement of said conveyor members along said path whereby one of said cavities in a mold block is filled with molten metal and a casting is ejected from the cavity in another block while the mold blocks are stationary.

3. In a metal casting machine, a pair of endless conveyor members movable in unison and in spaced parallel vertical planes along an endless path having a substantially horizontal, elongated reach, a multiplicity of mold blocks carried by said conveyor members, each of said mold blocks being formed with a mold cavity extending to the outer face of the block, a molten metal supply trough having a bottom surface extending in the plane of the upper surfaces of the mold blocks in their movement along said reach of said conveyor, said trough having a bottom opening disposed at a fixed elevation to discharge metal into said cavities, a pipe for supplying an excess of hot molten metal continuously to said trough at a point adjacent to said opening, said trough being disposed to return excess metal continuously to a source of supply by gravity flow, a closure for said opening operative to control the flow of metal to the mold cavities, said closure being continuously immersed in the stream of hot metal flowing in said trough, a horizontally elongated guide for said mold blocks extending along said reach of the conveyor members and disposed to slidably support the mold blocks beneath said trough and means for resiliently supporting said guide whereby said mold blocks are supported in sliding contact with the bottom surface of said trough.

References Cited in the file of this patent UNITED STATES PATENTS 486,809 McCaslin Nov. 22, 1892 866,607 Weimer Sept. 17, 1907 1,248,453 Carr Dec. 4, 1917 1,272,887 Ayers July 16, 1918 1,316,471 Acton et al Sept. 16, 1919 1,768,534 Aiken July 1, 1930 1,898,722 Ford Feb. 21, 1933 2,236,471 Eppensteiner Mar. 25, 1941 2,278,815 Winkel Apr. 7, 1942 2,292,266 Friden Aug. 4, 1942 2,364,615 Beckes Dec. 12, 1944 2,389,983 Johnson et al Nov. 27, 1945 2,459,892 Palmer et al. Jan. 25, 1949 2,629,150 Scott Feb. 24, 1953

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