US2984390A - Shell mold multiple pump system - Google Patents

Description

May 16, 1961 R. H, MOORE 2,984,390

SHELL MOLD MULTIPLE PUMP SYSTEM Filed Nov. 14, y1958 4 Sheets-Sheet 1 EQ F2-l NQE'NQOR RUSSELL H MOORE glas-.5 Shk ATTORNEY May 16, 1961 R, L.. MOORE 2,984,390

SHELL MOLD MULTIPLE PUMP SYSTEM Filed Nov. 14, 1958 4 Sheets-Sheet 2 y-v-i 17-2,

/NVE/v TGR I@USSL-"LL H. MOO/QE BY (J, may 627mm* AWRNEY May 16, 1961 R. H. MOORE 2,984,390

SHELL MOLD MULTIPLE PUMP SYSTEM Filed Nov. 14, 1958 4 Sheets-Sheet 3 lll 1^/ VEA/TOR RUSSELL A400/QE BYCJGGASWJQHH ATTORNEY May 16, 1961 R. H MOORE SHELL MOLD MULTIPLE PUMP SYSTEM 4 Sheds-Sheet 4 Filed Nov. 14, 1958 A TTORNE Yl ritited States Patent@ SHELL MOLD MULTIPLE PUMP SYSTEM Russell H. Moore, Gladstone, Va., assignor to Lynchburg Foundry Company, Lynchburg, Va., a corporation of Virginia Filed Nov. 14, 1958, Ser. No. 773,983

2 Claims. (Cl. 222-255) The present invention relates to metal casting, by means of shell molds, particularly method and means for gluing together superposed shell mold sections.

In the prior art various means have been employed for joining or gluing together shell mold sections. Conventionally, such sections are joined by the application of a dry or liquid thermosetting resin component to llat surfaces of one of two halves of a shell mold and thereafter compressing the same together. Some systems include the utilization of corresponding tongue and groove in mold sections; however, there has not been provided satisfactory means for conveying a uniform quantity of glue into such depressions.

As a result of these shortcomings there involves, quite often, the deposit of either too much or too little glue on the shell. When too much glue is deposited it separates the two halves of the shell mold thereby increasing the parting line dimensions of the resultant casting. This increased parting line dimension will make the casting dimention beyond tolerance and the result is a scrapped casting. When too little glue is deposited the two shell halves do not adhere satisfactorily and either the shell mold must be scrapped or if metal is poured into such shell molds the castings are lost. Also when it is necessary to apply dry thermosetting resin near the mold cavities the dry powder tends to drift into the cavities and causes poor casting finish.

All of the above shortcomings are overcome by the instant mutiple pump system, wherein a given quantity of glue is deposited into a plurality of strategically placed depressions in one half of the shell mold, with the other half of the shell mold having a corresponding boss for each depression and clearance is provided between each depression and each boss to prevent any glue from coming onto the hat surfaces of the shell halves but still gluing the two halves of the shell mold firmly together.

Another shortcoming of prior art systems resides in the use of templates for holding the glue pump applicators. Of necessity, these have been tailored individually in size and conformation to the shell mold sections being glued together. As a result, much time and money has been lost in developing complete separate templates and glue reservoirs for each sheld mold application. Additionally, the great time and effort required to clean and replace these templates is a problem which adversely affects the productivity per capita.

According to the present invention, a plurality of pumps are selectively positioned within a permanent glue reservoir. Flexible outlets lead respectively from said pumps and are removably disposed with respect to the surfaces being glued by a suitable and inexpenisve template. The template or glue dispensing tube guide does not serve simultaneously as a glue reservoir and hence it is not soiled during each use. Outlet glue dispensing tubes not required during a particular application may be inserted in suitable openings atop the pressure plate so that glue pumped therethrough is simultaneously returned to the reservoir. Check valve and spring retarding means in each of said pumps insure that a partial vacuum is maintained in the outlets during non-pumping and thus unscheduled dripping of glue is prevented. As a result, accurately measured quantities of glue may be deposited upon the selected shell mold half or section having suitable depressions or grooves for glue deposit,

Accordingly, it is an object of invention to provide a shell mold gluing system, means for accurately depositing measured quantities of .liquid glue upon shell mold sections.

Another object is to provide in shell mold sections recesses or grooves for holding glue and corresponding bosses or tongues partially fitting into such recessesY to sealingly join mating shell mold sections without deposit ing glue on the flat surfaces of said shell :mold sections.

An additional object of invention is to provide a liquid dispensing shell mold gluing system which is substantially universally adaptable to various shell mold section designs.

Additional objects of invention will become apparent from the foregoing preamble and ensuing description and attached drawings wherein like numbers designate like elements.

Figure l is a side elevational view partially in fragment of a multiple pump shell mold system in accordance with the invention .applying glue to a supported shell mold section;

Figure 2 is a sectional view taken along section line 2 2 of Figure l, showing a plurality of pumps mounted in a glue reservoir with overhead pressure plate abutting plungers of said pumps;

Figure 3 is an enlarged sectional view of one form of glue pump showing plunger and valving means positioned within the pump cylinder; and

Figure 4 is an enlarged phantom section view of the joining of shell mold sections by glue means adhering to corresponding portions of glue recesses and bosses; and

Figure 5 is a rnodied glue pump assembly in side elevation, partially fragmentary.

In Figure l, glue reservoir 18 is illustrated as mounted upon laterally adjustable frame 10 by means of transverse supports 38 and braces 46. Frame 10 is mounted upon yoke 40 which is pivoted upon upright bolt 42 in support 44. Pressure plate 14 adjustably covers reservoir 1S and is vertically actuable by means of piston system 12, the same being attached to frame 10 by means of bolts 50. interconnecting piston 12 and pressure plate 14 is a steel cylinder rod which lits into rod end ange 32. For access to reservoir 18, removable side plate 16 is employed. Adjusting bolts 34 are provided at either side of pressure plate 14. During the downward thrust of pressure plate 14, bolts 34 strike abutments 36 which are suitably welded to angle bar supports 38. Glue filler spout 20 is provided at the front of the reservoir 18. In Figure l the liquid glue shell mold pumps, generally designated as 22, are shown as removably interconnecting glue reservoir 18 and template 24.

In Figure 1 shell mold section 26 having glue recess 80 is shown as supported upon support plate 4S having common projections 28. See also Figure 4. Springs 30 encircling upright members 2S provide desired upward pressure, forcing a lower shell mold half against its upper counterpart to seal the respective halves together. A corresponding assembly, not shown, engages the upper half of the mold in actual practice. Template 24 may consist of 1736 inch steel metal and may have as many as 64 apertures which correspond to the 64 outlets provided in the presently used shell mold reservoir assembly 18 with adapters. However, the invention is: not to be thus limited as it will be apparent to those skilled in the art that any number of geometrically disposed apertures may be provided.

As shown in Figures 2 and 3, pump .22 consists of upright cylinder 58, housing the plunger 56. This plunger is urged upwardly by spring 34 principally. Cylinder 58 is positioned in the outlet holes 54 of the reservoir bottom so that cylinder apertures are .substantially adjacent the bottom of glue reservoir 18. Thus, tirst use of the oldest glue in the reservoir is insured, the glue concentrates being first available for pumping. This is a principal distinction over other gluing pumps wherein intake apertures are disposed well above the bottom of the old pan-type reservoir. Threadedly engaging the bottom of cylinder 58 is ball check valve housing 62. Ball check valve 64 seats upwardly against cylinder 58 and moves vertically between valve seat and the top of coupling 72. Check valve spring 66 urges the ball check valve toward shoulder 70 and override spring 68 retards the return movement of the ball check valve to its seat 70. In pumping, valve 64 will often rest atop coupling 72 in which Vslots 71 permit liquid glue flow into the `coupling interior. Delay of the seating of the ball check valve on its upper and only valve seat insures that a portion of the total glue volume in the flexible tube nozzle outlet 78 is retained therein as against dripping upon Completion of a measured deposit. A vacuum is thus insured in each flexible tube 74 to the extent that glue is removed from the lower nozzle outlet 78 and dripping is positively prevented.

Threadedly engaging the ball check housing 62 is tube coupling 72. As shown in Figure 2, flexible tube 74 is connected to coupling 72 and has nozzle outlet 78 at its lower end. Swivel nut 76 is provided intermediately t0 removably engage template 24. As indicated by Figure 1, nozzles 78 which are not required during a particular application, may be inserted in suitable openings atop the pressure plate so that glue pumped through idle .tubes is simultaneously returned to the reservoir.

As Will be seen in Figure 4, a schematic shell mold section 26 is provided with a plurality of glue recesses 80; Corresponding shell mold section 29 adjoined thereto is provided with corresponding bosses 82, the latter partially tting into recesses 80, dissipating the scheduled and measured quantity of glue 52 lwithin recess 80 only and thus avoiding setting up. The measured quantity is obviously determined by the vertical stroke of pump 22 and this stroke is in turn established by adjustment of bolt 34 with respect to its aligned abutment 36. (See Figure l.)

Referring now to Figure 5, wherein a modification of glue dispensing sub assembly is depicted, it will be noted that the valve mechanism is disposed in the template engaging head. Cylinder engages the reservoir 18 at its floor through threaded contact. The cylinder includes glue intake apertures 112, opposed to each other and the cylinder houses plunger with return spring 122 being compressed between plunger head and cylinder top. Coupling 124 joins cylinder 110 and fitting 126 to provide a base for the flexible `hose 128. At the lower end of Yhose 128 a tting 130 ogether with barrel .140 retains magnet 132 in position. The magnet is adapted to secure the dropper 142 to the template which is of magnetizable substance. Barrel carries dropper 142 in extension and a valve seat 144 near its top. Check valve 146 seats against the shoulder 144 as plunger 120 is released, but upon depression of the plunger the valve will become unseated permitting fluid to ow as in the previous modification. Note the by-pass grooves at the top of dropper 142 accommodating uid by-pass should the valve seat onto the top of dropper 142 by compression of spring 148.

Manlfestly, the present invention may be applied to the measured application of other fluids or liquids to speciiied areas by means of suitable templates. 1t is to be understood that the forms of invention, herewith shown and described, are to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts maybe resorted to, without departing from the spirit of invention, or the scope of the subjoined claims.

I claim:

1. A multiple pump system for gluing shell molds comprising a glue reservoir; a vertically adjustable pres,- sure plate, said pressure plate encompassing said reservoir; a multiplicity of glue pumps mounted within said reservoir and abutting said pressure plate, each said pump including a cylinder extending through the bottom of said reservoir and having an intake aperture within said reservoir for withdrawal of glue through said cylinder, a plunger slidably mounted in said cylinder adjacent said aperture, and a spring tensioned ball check valve supported at the end of said cylinder outside of said reservoir, said ball check valve being closed against a seat in said cylinder by spring means, whenever said plunger is not pumpingly depressed by vertical actuation of said pressure plate, said ball check valve thus creating a partial vacuum in the outlet of said pump system and flexible outlets attached to each of said ball check valves and spacedly retained at their respective outlet ends by a template, said outlets being individually utilizable so that those not required during a particular gluing application may be attached to said pressure plate for return of pumped glue to said reservoir during pumping.

2. A multiple pump system as in claim 1, said ball check Valve including pressure spring override means intermediate said plunger and said valve seat.

References Cited in the le of this patent UNITED STATES PATENTS 765,731 Hooton et al. July 26, 1904 921,594 Crane May 11, 1909 1,582,092 Stacy Apr. 27, 1926 1,637,613 Johnson Aug. 2, 1927 1,698,023 Mathewson a Ian. 8, 1929 1,793,978 Ward Feb. 24, 1931 2,296,861 Matter Sept. 29, 1942 2,312,625 Cathey Mar. 2, 1943 2,597,175 Perkins May 20, 1952 2,670,877 Logue Mar. 2, 1954 2,734,667 Conklin Feb. 14, 1956 2,771,225 Perkins Nov. 20, 1956 2,800,931 Sutcliie July 30, 1957 2,902,860 Glass Sept. 8, 1959 2,942,622 Hahan et al. June 28, 1960

Images