US2787815A - Journal bearing casting apparatus - Google Patents

Description

April 9, 1957 c GRANADE ET AL 2,787,815

JOURNAL. BEARING CASTING APPARATUS Flled March 25, 1955 5 Sheets-Sheet l INVENTORS Fred C. Grenade George H. A. Ruby fwfiz AGENT April 9, 1957 F. c. GRANADE E L 2,787,815

JOURNAL. BEARING CASTING APPARATUS Flled March 25, 1955 5 Sheets-Sheet 2 40 I \g 1 iIiI mun 48 ulm 5 1 26' 26* ll w R "fkfiQ'ikK "rk 0 l I I INVENTORS l 46 Fred G. Grenade 7 BY George H. A. Ruby 44 50 K 52 A GENT 6 Sheets-Sheet 3 F. C. GRANADE ET AL JOURNAL BEARING CASTING APPARATUS 3 n El m m IIII i a .p. i, i u l II II v ML m I] m v\ II a w w a A ril 9, 1957 Flled March 25, 1955 April 9, 1957 c, GRANADE ET AL JOURNAL BEARING CASTING APPARATUS 6 Sheets-Sheet 4 Flled March 25, .1955

INVENTQRS Fred C. Grenade BY George H. A. Ruby Wfg h AGENT April 9, 1957 F. c. GRANADE ETAL 2,787,815

JOURNAL BEARING CASTING APPARATUS Filed March 25, 1955 6 Sheets-*Sheet 5 Fig. 7.

INVENTORS Fred C. Grenade AGENT BY George H. A. Ruby wffimw Aprll 9, 1957 F. c. GRANADE E AL 2,787,815

JOURNAL BEARING CASTING APPARATUS Filed March 25, 1955 s Sheets-Sheet e INVENTORS Fred 0. node BY George H. Ruby M AGENT United States Patent JOURNAL BEARING CASTING APPARATUS Fred C. Granade and George H. A. Ruby, Chicago, 111., assiguors to National Lead Company, New York, N. Y., a corporation of New Jersey Application March 25, 1955, Serial No. 496,652

4 Claims. (Cl. 22-57) 'This invention relates to casting apparatus. More specifically, it relates to an automatic casting device for the production of journal bearing members. Further it relates to a process for making such members. Still more specifically it concerns an improved mold construction useful in the production of journal bearings and the like.

Heretofore journal bearings have, for the most part, been produced by employing sand molding techniques as are practiced in the foundry art. It is recognized that such techniques, wherein it is necessary to prepare and process a separate mold unit, involving several operations, for each bearing member, are undesirable. The many steps which are required according to prior art practice are time-consuming, expensive, and do not always result in products of uniform dimensions or quality. The instant invention, however, overcomes the disadvantages of such prior art methods and apparatus and permits the production of a maximum number of uniform journal bearing members or the like with a minimum of time, equipment, and operating personnel.

An objective of the instant invention, therefore, is to provide apparatus for continuous and eficient production of journal bearings. Another object is to provide apparatus and means for producing cast objects such as journal bearing members, which objects upon casting possess dimensions within tolerance limits heretofore not considered possible. A further object is to provide an improved method for automatically casting journal hearing members. Still another object is to provide a new and unique mold design for casting members of this type. These and other objects of the instant invention will become apparent from the following more complete description and from the drawings wherein:

Fig. 1 is a schematic representation of apparatus, in

front elevation, constructed according to the instant invention;

Fig. 2 shows the apparatus along line 22 of Fig. 1, the apparatus being generally in closed position;

Fig. 3, in side elevation, shows the apparatus in intermediate open position;

Fig. 4 represents the instant apparatus, in side elevation, in full open position;

Fig. 5 shows a side view of a typical mold construction employed according to the instant invention;

Fig. 6 shows the mold construction along line 6-6 of Fig. 5;

Fig. 7 is a top view of the mold taken along line 7-7 of Fig. 5 and Fig. 6; e

And wherein Fig. 8 shows the closed mold in section and partially cut away to more clearly illustrate the details of the mold cavity formed by the plurality of parts.

Finally, Fig. 9 is a top sectional view of a typical journal bearing cast in the apparatus of this invention and Fig. 10 is a bottom sectional view of the same bearing.

Briefly the instant invention comprises a. combination of elements so arranged as to produce a unitary apparatus and process for automatic casting. The mold in closed position is filled with molten metal; the metal iscooled 'ice to give a solid casting; the mold is opened; the casting shown) which in turn is activated by a solenoid timing device or equivalent mechanism (shown only schemati cally at 14). The piston is connected to upper carrier plate 16 and to middle carrier plate 18. These two carrier plates are operably joined to lower carrier plate 20, which in part forms and supports and carries the top section of the mold. As previously indicated the mold design is of new and unique construction which will be In the instant ernhereinafter described in greater detail. bodiment as shown the piece to be cast is a journal hearing, and the top section of the mold comprises a number of sections necessary to give the desired shape and includes bore form section 22, and contour plates 24. Disposed generally within and protruding through bore form section 22 when in full open position are knock out pins 26. The upper section of these knock out pins extends through and beyond upper carrier plate 16 and is so disposed that it contacts the top anchor plate 28 in the upward movement of the apparatus. This action forces the pins down and out of the bore form section, causing I the cast piece to be loosened and ejected therefrom. The

knock out pins are provided with spring 30 which is compressed during the knock out or ejection operation.

Release of the compression during the downward movement of the apparatus forces the knock out pins to move back into the interior of the bore form section.

The piston, carrier plates and top section of the mold are disposed between and movably adjoined by means of guide blocks 32 to a pair of vertically positioned tie and guide bars 34. The movable upper assembly travels along these tie and guide bars which are in themselves tied into the lower portion of the apparatus such as. the base and bottom section of the mold.

Still considering the apparatus in full open positionp' there is in place the discharge plate 36 which is adapted to receive the ejected casting and assist in the removal of same from the vicinity of the casting apparatus. The

discharge plate 36 is supported by a pair of discharge H plate arms 38 which are pivotally connected to the casting apparatus in such a manner that the discharge plate may be moved into position to receive the ejected casting and then out of said position to permit movement of the casting apparatus preparatory to forming a new piece. In the instant case a pair of discharge plate earns 40 from the discharge plate.

in timely movement of the discharge plate into receiving position.

maining portion of the operational cycle. There may also be provided, if desired, a set of counterbalances to permit easiest movement of the entire discharge plateassembly.

Looking now at the bottom part of the instant apparatus, there is a base section generally defined as 44 in the drawings. Situated just above this section and supported thereon are the bottom sections of the mold itself. Again i it is repeated that the details of the complete mold assembly will hereinafter be more completely described. Briefly the bottom sections comprise two operably connected f Further it provides for removal of the dis- 1 charge plate from the receiving position during the rep of the mold that when. the apparatus is in fully closed:

position there is formed a mold cavity. having the configuration of the molded piece together, with a suitable opening for introducing. molten metal. member 46 is in a generally nonmovable position While the pour gate member is capable of movement generally to and away from the front of the lower mold member. This movement isproperly andtimely effected by associ ation of the pour gate lugs SO-Witha pair of pour gate cam bars 52 which are attached to the upper carrier plate 16 and move in. conjunction therewith.

Suitable heating means as for instance gas burners or electric heaters may be positioned adjacent the various parts of the moldassembly so as to permit heating these parts to the required temperatures. Obviously heat may be effectively transmitted to the upper mold section by placing this in closed position for a suitable period of time while operating the particular type of heating device which is employed.

Following through a typical operational cycle we can consider that a number of pieces have been cast and that the apparatus is in full open position as shown in Fig. 4. A cast piece has just been ejected, and the empty top mold section is beingicooled slightly by blowing air on it under predetermined conditions of pressure and time. The timing device has previously been set for the desired operating cycle and the solenoid 14 now activates the hydraulic cylinder 12 which sends the piston 10, carrier plates 16, 18- and the upper mold section moving downward. The vertical movement both upward and downward, of couse, is controlled and guided by the tie and guide bars 34. As the upper section moves downward the knock out pins 26 are released from contact with the top anchor plate 28. The springs 30 are thus enabled to expand to their open position and cause the knock out pins 26 to be drawn back intothe interior of bore form section 22. As the piston and attached assembly moves downward'discharge plate cams 40 engage the discharge lugs 42: and force the discharge plate arms 38 and discharge plate 36 away from the receiving position and to the rear of the apparatus, where the discharge plate assembly will remain until later in the operation. The piston and upper mold section continuesdownward until the bottom'sun faces of the upper mold-section-contact the top surfaces ofthe lower mold member. When the mold is'in this position of contact, the pour gate member 48 has not yet moved into casting position. The pour gate cambars 52 which as previously stated are attached to upper carrier plate 16, however, continue to move downward with the upper carrier plate for an additional distance equal to the opening between the upper carrier plate 16 and middle-carrier plate 18 when the apparatus is in full open position. This additional movement of the pour gate cam bars cause them to contactthe pour gate lug surfaces 50, which action forces the pour gate to move upwardly and inwardly thereby contacting the front of the lower mold member. The pour gate is preferably spring. loadedand when in position, there is a positive pressure of approximately 800 pounds per square inch forcing. the pour gate member in close contact with adjacent mold surfaces. This pressure has been found sutlicient to prevent leakage of the molten metal through the mold apertures when the castingis made. The additional downward movement of the assembly until the upper carrier plate 16 meets the middle carrier plate 18 results in a substantial hydraulic pressure being exerted on the mold assembly and'thus insures a casting operation free 7 from leakage.

With the moldcompletely'assembled and in closed position as illustrated in Fige-l, the apparatus is ready for a pour; The molten metal which ordinarilyis at tempera The lower mold ture varying between 1500 and 2100" F. is poured into the closed mold through the pour gate. This operation may be manual or may be made automatic or semi-automatic as is known to the art. The actual pouring operation for pieces the size of journal bearings usually only takes several seconds, say ten or twelve. The automatic timing mechanism is activated as soon as the pouring oper-ation is completedythe casting is permittedto form and the mold remains closed for a predetermined period. The unique construction-of the mold insures rapid and uniform dissipation of heat from the cast piece'at this stage. The timing mechanism then activates the hydraulic cylinder and the separation of the mold section starts. This is considered to be the upward movement of the apparatus and occurs as follows, being roughly the reverse of the operation just described.

The first upward movement of the piston 10 carries the upper carrier plate 16 out of contact with the middle carrier plate 18. Simultaneously the pour gate cam bars 52 disengage the pourgate lugs 50 and force the pour gate member 50 outward and downward with a hard thrusting action. As-the pour gate moves in this manner it separates from the sprue or-neck piece resulting from the pouring operation. This sprue can easily be knocked off from the cast piece at a later time. While the pour gate is thus separated from the other mold parts the piston continues to move upward and the'middle carrier plate 18', lower carrier plate 20, and uppermold members 27. and 24 also begin to move upward. The cast piece remains attached to the upper mold member and. rises with it, thus becoming free from the lower section. As the assembly continues upward, the discharge plate cam surfaces 40 engage the discharge plate lug surfaces 42 and begin to move the discharge plate 36 into receiving position beneath the upper mold member. The top of the knock out pins 26 engages the top anchor plate 28 and the knock out pins are driven down and out of the bore form section 27., thus ejecting the cast piece from the upper mold section. The casting falls downward onto the discharge plate which action carriesit away from the apparatus. The mold parts are cooled automatically as required'and the apparatus is once again ready to continue its cycle of operation.

As previously indicated the construction of the mold employed in theinstant invention is considered to be unique and adefiniteimprovement in the art. The mold consists of aplurality of sections such as the upper mold section, the. lower mold. section, and, the pour gate sectiorn. Assembly of. these as described results in a com plete mold; Because. of the close tolerance to which these parts are constructed. it has. been found possible to avoid-leakage ofthe molten metal provided appropriatepressure-isvemployed to maintain the sections in juxtaposition with one another. Moreover, each of the above mentioned sectionsof itself is made up of a plurality of interloekingmold segments. These interlocking segments-are constructed of alloys having specific heat conducting properties and are designed in thickness and cross section-to give the best degree of heat dissipation where employed in the complete mold. Temperature control and heat transferare very important particularly when casting pieces-ofbronze. The lead constituent of the bronze apparently tends to sweat out and not only gives an inferior casting but also tends to damage the mold surfaces. By the instant construction it has been found possible to replace any part of the mold which becomes unusable for one reason or another. Such replacement 'of one part is. simple and-results in signiiicant savings in: time andexpense. Since the instant molds are made within tolerance limits heretofore not considered practical, it is obvious that the necessity to discard'an. entire mold-simply because one section was no longer satisfactory would be: mostundcsirable.

A typical mold constructed according to the instant invention: is illustrated in the drawings, particularly Figures" 5-8; For example-the" upper mold section comprises a plurality of parts including the lower carrier plate 20, bore form section 22, and contour plates 24. The lower mold member 46 includes side form segments 60, back form segment 54 and if desired, name plate segments 56. The pour gate member 48 likewise comprises a plurality of replaceable segments of predetermined thickness. The individual replaceable mold segments are all machined to extremely close tolerances and when assembled as indicated in the drawings produce a tight mold with no leakage problem whatsoever.

Thus it is seen that the apparatus of this invention provides for improved casting of journal bearings and similar cast pieces. In particular the unique mold construction permits the establishment of an automatic and continuous casting operation whereby shaped pieces may be cast to precision heretofore not considered possible.

While the invention has been described by the preceding example and drawings, which are directed to the production of journal bearings, it is not intended to be limited thereto, and other modifications and variations may be employed within the scope of the following claims.

We claim:

1. In casting apparatus of the class described, a casting mold comprising a stationary bottom mold section, a movable upper mold section, and a pour gate section relatively movable to said bottom section, a hydraulically motivated piston operably connected to said movable upper mold section, vertically positioned guide and tie bars for supporting the casting assembly and for guiding the movement of the upper mold section, means for moving the pour gate section comprising pour gate cam bars arranged for controlled movement according to the position of the upper mold section and pour gate lugs attached to the pour gate section and arranged to con tact said pour gate cam bars, means for ejecting the casting from said upper section, means for receiving the ejected casting and for transferring same away from the apparatus comprising a discharge plate arranged to move in position generally below the upper die section when same is in open position, the means for moving the discharge plate comprising a pair of discharge plate lugs positioned on the supporting arms of the discharge plate and arranged to contact and move in cooperation with a pair of movable discharge plate earns, the movement of said discharge plate cams being in controlled relationship to the movement of the upper mold section.

2. Casting apparatus according to claim 1 wherein the means for ejecting the casting from said upper section comprises at least one movable rod member, the bottom end of which is normally flush with the casting face of the upper mold section, the upper section of the rod member extending through and beyond the upper die sec tion and designed to contact a fixed stop member when the upper mold section is raised thereby forcing said mow able rod member down and against the casting in order to eject the casting.

3. Casting apparatus according to claim 2 wherein the movable rod member is provided with a spring which is loaded during the ejection operation, the spring loading causing the rod member to retract when the upper mold section moves downwardly.

4. Apparatus for automatic casting of journal bearings and the like comprising a casting mold having a stationary bottom mold section, a movable upper mold section, and a pour gate section relatively movable to said bottom section, a hydraulically motivated piston, operably connected to said movable upper mold section, vertically positioned guide and tie bars for supporting the casting assembly and for guiding the movement of the upper mold section, said upper mold section and piston being joined to said guide and tie bars by movable guide blocks, vertically positioned pour gate cam bars arranged in fixed relationship to said movable guide blocks, pour gate lugs attached to said pour gate section and arranged to contact the cam surfaces of said pour gate cam bars and thus move in relation thereto, a casting ejecting member for ejecting the casting from said upper die section, a movable discharge plate supported by discharge arms having lug surfaces positioned to contact and move in cooperative relationship with the cam surfaces of discharge plate cam members also vertically and fixedly joined to said movable guide blocks, and synchronized motivating means for operating the parts of the casting apparatus automatically.

References Cited in the file of this patent UNITED STATES PATENTS 783,577 Haggenjos Feb. 28, 1905 1,881,648 Jordhoy Oct. 11, 1932 2,076,374 King Apr. 6, 1937 2,425,362 Cherry et al. Aug. 12, 1947 2,635,310 Morgan Apr. 21, 1953 FOREIGN PATENTS 353,497 Great Britain July 22, 1931 594,155 France July 13, 1925

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