US3234602A

US3234602A - Self-aligning pouring cup pattern and sprue punch assembly

Info

Publication number: US3234602A
Application number: US239663A
Authority: US
Inventors: William A Hunter; Lund Robert
Original assignee: Pettibone Mulliken Corp
Current assignee: Pettibone Traverse Lift LLC
Priority date: 1962-11-23
Filing date: 1962-11-23
Publication date: 1966-02-15
Anticipated expiration: 1983-02-15

Description

Feb. 15, 1966 w. A. HUNTER ETAL 3,234,602

SELF-ALIGNING POURING CUP PATTERN AND SPRUE PUNCH ASSEMBLY Filed Nov. 25, 1962 2 Sheets-Sheet 1 FIG! 52 FIG. 2

INVENTORSI ROBERT LUND WILLIAM HUNTER W. A. HUNTER ETAL SELF-ALIGNING POURING CUP PATTERN AND SPRUE PUNCH ASSEMBLY Filed Nov. 25, 1962 Feb. 15, 1966 FIG. 4

INVENTORSZ ROBERT LUND' WILLIAM A. HUNTER United States Patent 3,234,602 SELF-ALIGNING POURING CUP PATI'ERN AND SPRUE PUNCH ASSEMBLY William A. Hunter, Morton Grove, and Robert Lund,

Melrose Park, 11]., assiguors to Pettihone Mulliken Corporation, Chicago, Ill., a corporation of Delaware Filed Nov. 23, 1962, Ser. No. 239,663 6 Claims. (Cl. 22-38) The improved pouring cup pattern and sprue punch assembly comprising the present invention has been designed for use primarily in connection with sand casting operations and during that portion of the process wherein the sand is being compacted about the pattern. When so used, the invention is applicable to both mechanized or automatic foundry installations as Well as conventional manual flask procedures. The invention is, however, capable of other uses and a pouring cup pattern and sprue punch assembly in accordance with the principles of the present invention may, with or without modification, be employed in connection with molding operations involving molds other than sand molds, for example, graphite, loam, and the like, whether the molds be formed of refractory or nonrefractory material and whether the molds be of the permanent or destructible type. Irrespective, however, of the particular use to which the present invention may be put, the essential features thereof are at all times preserved.

Heretofore, in sand molding operations, and particularly in present-day automatic molding machine operations, considerable difliculty has been encountered in eflecting proper sprue punch placement within the flask cavity. By way of further explanation and example, it is pointed out that the cope section of a mold is invariably provided with a pouring basin or depression which communicates with at least one sprue passage in communication with and leading to the mold cavity. This depression functions in the manner of a tunnel to conduct the poured molten metal to the sprue passages and from thence into the mold cavity. To form the depression and its associated sprue passages at the time of forming the cope section of the mold, cooperating pouring depression and sprue patterns are brought together within the flask at the time of flask-closure. These patterns move relatively to each other and in axial alignment during flask-closing operations. The pouring cup pattern is usually mounted on the blow plate above the flask and the sprue punch is, in most instances, mounted on and movable with the table of the molding machine so that as the table rises toward the blow plate, the sprue punch moves axially towards and finally into engagement with the pouring cup pattern. The particular difliculty which is involved in connection with this procedure resides in the fact that either a close tolerance in the height of the flask and the eflective length of the sprue punch must be maintained or a lost-motion connection of some sort must be provided between the sprue punch and pouring cup pattern. In the matter of tolerances, excess flask height leads to a 1oosely-positioned sprue punch, while insufficient flask height leads either to the inability of the flask to close or to bending or other damage to the sprue punch or the pouring cup pattern. In the matter of a lost-motion connection, it has been the practice to provide in the pouring cup pattern a bottom opening which is slightly larger than the overall diameter of the sprue punch so that when the punch enters the opening in the pouring cup pattern, there will be an annular clearance between the punch and the rim of the opening to prevent binding of the parts. With such structures, upon separation of the parts and withdrawal of the sprue punch from the bottom opening in the pouring cup pattern, an appreciable amount of sand in a fairly loose state will adhere to the sprue punch, as well as to the rim of the bottom opening in the pourmg cup pattern, thus making it necessary to ream or otherwise remove surplus sand from the sprue openings in the flask. The removal of surplus sand from the sprue openings in a flask is a time-consuming operation, and where mechanized operations are concerned, complicated sprue reaming equipment including a reamer proper, a motor for rotating the reamer means for advancing and retracting the reamer into and out of the sprue passages, and various control mechanisms for such instrumentalities, has been devised.

The present invention is designed to overcome the above-noted limitations and disadvantages that are attendant upon the use of conventional pouring depression and sprue passage forming devices and, toward this end, it contemplates the provision of a novel combination of a pouring cup pattern and sprue punch assembly wherein the punch is floatingly mounted upon the table or other portion of the machine which moves relatively to the pouring cup pattern during flask assembly operations, the floating mounting including a yielding lost-motion connection between the punch and the table or other portion of the machine which supports it, the lost-motion take-up occurring in an axial direction with initial engagement and interlock between the pouring cup pattern and punch taking place well in advance of final flask-closing operations so that a lack of tolerance resulting in even an inordinate excess of flask height will not contribute to sprue punch looseness, while a lack of tolerance resulting in an inordinate lack of flask height will not cause bindiigkof the sprue punch or prevent proper closing of the The provision of a pouring cup pattern and sprue punch assembly of this character being among the prinicpal ob jects of the invention, it is a further object to provide such an assembly wherein the pouring cup pattern and sprue punch are self-aligning, which is to say that, as the adjacent end of the punch moves into cooperating engagement with the pouring cup pattern, alignment between the punch and pouring cup pattern takes place automatically.

A still further object is to provide a pouring cup and sprue punch assembly of the character under consideration and wherein relative movement between the sprue punch and pouring cup pattern terminates substantially immediately upon initial engagement between the two parts, while at the same time, continuity of surface contour between the parts is effected, thus eliminating the presence of crevices, pockets or other voids at the juncture between the parts and into which sand particles might otherwise accumulate.

With these and other objects of the invention in view, which will not at this time be enumerated but which will become apparent subsequently, the invention consists of the novel construction, combination and arrangement of parts shown in the accompanying two sheets of drawings forming a part of this specification and in which:

FIG. 1 is a fragmentary sectional view, somewhat schematic in its representation, showing one form of the improved pouring cup pattern and sprue punch assembly operatively installed in the flask of an automatic molding machine for producing mold cope sections, the view being taken substantially centrally and longitudinally through the flask and showing the blow plate, flask and table closed upon one another and the flask filled with sand preparatory to the usual squeeze operation;

FIG. 2 is an enlarged sectional view taken on the line 2-2 of FIG. 1;

FIG. 3 is an enlarged sectional view taken on the line 3-3 of FIG. 1;

FIG. 4 is a fragmentary sectional view similar to FIG.

1 but showing another form of pouring cup pattern and FIG. 4.

Referring now to the drawings in detail, and in particular to FIGS. 1 to 3, inclusive, a pouring cup pattern and an associated sprue punch 12, both constructed according to the principles of the present invent-ion, have been shown as being embodied in a simplified form of molding machine, only the essential elements of which have been illustrated. The molding machine has been designated in its entirety by the reference numeral 14 and is designated for use in the making of the cope section of a mold.

The molding machine involves in its general organization a squeeze board 16, the purpose of which is to compact molding sand 18 in a flask 20 containing a pattern 22. The sand, when compacted about the pattern 22, provides the cope section of a mold. The pattern 22 is supported upon a pattern plate 24 which is fastened as at 26 to the squeeze board 16. The flask 20 is clamped against a blow plate 28 under the influence of the upward pressure of .an upper table section or extension 30 which, in turn, is

supported upon a lower or main table section 32. The table section 32 is carried at the upper end of a vertically reciprocable ram 34. It is generally of cup-shaped configuration, and within this section, squeeze cylinders 36 .cooperate with squeeze rams 38 to elevate the squeeze board 16 immediately after the hereinafter mentioned blowing operation in order to compact the loose sand in the flask about the pattern 22 in the usual manner of molding machine operation. Fluid is supplied to the cylinders 36 through fluid lines 40. The flask 20 is provided with lateral supports in the form of flanges 42 which are designed for cooperation with arresting stops or abutments 44 form-ing a part of the molding machine framework so that after the sand compacting operation has been completed and the ram 34, the

table sections

30 and 32, and the flask 20 lowered bodily as a unit, the flask 20 will be arrested in its downward movement by the abutments 44 to the end that the formed cope section of the mold may be removed or stripped therefrom.

The arrangement of parts thus far described is purely conventional and no claim is made herein to any novelty associated with the same, the novelty of the present invention residing rather in the novel construction, combination and arrangement of the parts, including the pouring cup pattern 10 and the sprue punch 12, and such parts 'introduced into the flask through blow holes 46 in the blow plate, and numerous other details, essential or otherwise, have not been illustrated, these being well-known in the art.

Still referring to FIGS. 1 to 3, inclusive, the pouring cup pattern 10 may be'regarded as constituting a part of the blow plate 28 and is generally of frusto-conical configuration. As shown in the drawings, the large base 50 of the pouring cup pattern is secured by fastening screws 52 to the bottom or underneath face 54 of the blow plate 28. The pouring cup 10 may be formed of any suitable material as, for example, steel, and in the illustrated form thereof it is shown, as being solid. The small base 56 of the pouring cup pattern is provided with a small conical socket'58, the purpose of which will be made clear presently.

The sprue punch 12 is in the form of an elongated steel rod and has a pointed or conical upper end 60 (see FIG. 2) which is designed for mating engagement with the conical socket 58 when the punch and pouring cup pattern are brought into register and contact.

The lower end of the sprue punch 12 is formed with a cylindrical socket 62 which forms a seat for a spring 64. The upper end of the spring 64 seats against the bottom wall of the socket 62 while the lower end of the spring seats on a horizontal flange 66 on a bracket 68. The latter has a foot portion 70 which is secured by fastening screws 72 to the table 32. A second horizontal flange 74 is bifurcated as at 76 and the bifurcated portion thereof extends into an annular groove 78 which is formed in the lower end region of the punch 12 and straddles the reduced section of the punch that results from the annular groove 78. The weight of the sprue punch 12 is thus borne by the spring 64, and the punch is capable of limited vertical shifting movements relatively to the bracket 68 within the limits aflorded by the confining action of the annular groove 78.

The sprue punch 12 extends vertically. It projects upwardly through

respective openings

80 and 82 in the squeeze plate 16 and the pattern plate 24 and is slidable vertically in these openings in opposite directions during ram-raising and ram-lowering movements. The bracket 68 and the

openings

80 and 82 are so disposed and are of such size that the upper end of the sprue punch 12 is maintaincd in approximate vertical register with the conical socket 58 in the small base 56 of the pouring cup pattern 10.

In the operation of the pouring cup and sprue punch assembly of the present invention, upward movement of the

table sections

30 and 32 for flask-closing operations in the usual manner of operation of a molding machine of the type under consideration will carry or move the bracket 68 upwardly, thus moving the sprue punch 12 upwardly under the influence of the spring 64 upon which it is supported. As soon as the pointed upper end 60 of the punch engages the wall of the conical socket 58 in the small base 56 of the pouring cup pattern 10, the punch will, by a camming action against such wall, become aligned with the pouring cup pattern, alignment being completed when the pointed end of the punch seats squarely within the socket 58. Thereafter, any further upward movement of the ram and table will serve to compress the spring 64. The width of the annular groove 78 is such that freedom of floating movement of the punch with respect to the bracket 68 is available throughout a range of movement in excess of the difference between maximum and minimum tolerance discrepancies in the manufacture of the flask 20 so that an unduly high flask will establish no looseness in the sprue punch 12, or an unduly low flask will create no binding of the punch.

In FIGS. 4 to 6, inclusive, a difierent form of the invention has been shown wherein a pouring cup pattern and a sprue punch 102 cooperate to produce the necessary pouring depression and its associated sprue passage in the cope section of a mold which is undergoing formation in a match-plate mold-forming machine which has been designated in its entirety by the reference numeral 104.

The machine 104 involves in its general organization a squeeze board 106, the purpose of which is to compact the loose molding sand 108 about a cope pattern 110 which is contained within the cope section 112 of a flask. The pattern is supported on a match-plate 114 which bears upwardly against the flask section 112 during the sand-compacting operations. Conventional registration pins 116 for inter-engaging relationship with corresponding openings 118 at the corners of the flask section 112 serve to align the flask section with the match-plate, and

also with the lower movable drag section of the flask, a portion of which has been shown at 120.

The disclosure of the match-plate mold-forming machaine 104, like the disclosure of the molding machine 14 previously described, is a schematic one, and furthermore, only such portions of the machine 104 as bear a relation to the pouring cup pattern and sprue pin assembly of FIGS. 4 to 6, inclusive, have been illustrated. It will be understood, for example, that the plunger 122, which has been shown in FIG. 6 as being applied to the squeeze plate 106, constitutes the movable element of a press assembly (not shown) whereby the squeeze board and its associated devices may be moved downwardly for compacting the sand 108 within the flask section 112 while at the same time creating the impression of the pouring cup pattern in the cope section of the mold, and also for stripping the cope section of the mold from the flask and from the sprue punch 102, as Will be described in greater detail hereafter.

The pouring cup 100 is in the form of a sleeve having an enlarged conical head portion 130 and a reduced coaxial threaded shank portion 132. An axial bore 134 extends through the pouring cup pattern 100 and is designed for loose reception therethrough of the sprue punch 102. The shank portion 132 is threadedly received within an opening 135 provided on the squeeze board 106. Fastening screws 136 may be provided for holding the pouring cup pattern 100 in position on the squeeze board 106 with the enlarged head portion 130 underlying the latter and fitting closely thereagainst. The pouring cup pattern 100 preferably is formed of steel.

The sprue punch 102 is in the form of an elongated steel rod, the lower end of which is provided with a small conical socket 140 (see FIG. 5) which is designed for seating engagement with an upstanding conical protruberance 142 on a raised boss 144 on the match plate 114. The upper end of the sprue punch 102 projects into an inverted cup 146 which is carried on an attachment bracket 148. The latter forms a stationary part of the machine framework and is permanently attached to the bracket by a pin and slot connection 149 between the punch and the cup. The pin and slot connection 149 permits limited axial shifting movement of the sprue punch relatively to the cup. A spring 150 is interposed between the upper end of the sprue punch and the bottom wall of the cup 146 and serves normally to urge the punch downwardly to the limit of its motion as permitted by the pin and slot connection 149. The punch 102 projects loosely through the axial bore 134 in the pouring cup pattern 100 and is thus slidable through the pouring cup pattern. The lower end of the sprue punch is thus at all times maintained in axial alignment with the boss 144 and in axial register with the conical protuberance 142 thereon.

The operation of the pouring cup pattern and sprue punch assembly of FIGS. 4 to 6, inclusive, is similar to the operation of the pouring cup pattern and sprue punch assembly of FIGS. 1 to 3, inclusive, rising of the lower flask section 120 and the match-plate 114 bodily in unison taking place in the usual manner of operation of the machine to eflect closing of the two

flask sections

120 and 112 upon each other. As the match-plate approaches the limit of its upward movement, the small conical protuberance 142 enters the mating conical socket 140, and when the two conical surfaces are in full mating engagement, the sprue punch 102 becomes accurately positioned and aligned within the fixed flask section 112. Flask and sprue pin tolerance of a fairly wide nature are compensated for by the yielding action of the spring 150 which, in any event, becomes compressed so as accurately to position the sprue punch 102.

After the blow operation which fills the

flask sections

112 and 120 with loose sand, the squeeze board is forced downwardly under the influence of the plunger 122 and assumes an intermediate position such as has been shown 6 in dotted lines in FIG. 4, thus compacting the sand in the fixed flask section 112 about the pattern 110. A similar compacting operation takes place in the lower flask section 120 under the influence of a lower squeeze board (not shown). After these sand compacting operations are completed, the two flask sections are parted to enable the patterns to be removed. Finally, the two flask sections are again brought together and the ram 122 moves further downwardly, while at the same time, the upper and

lower flask sections

112 and 120 move downwardly bodily as a unit. During the downward movements of the squeeze board 106, both initially for sandcompacting operations, and finally, for mold-ejecting operations, the sleeve-like pouring cup pattern slides axially along the sprue punch 102, the latter remaining suspended by the pin and slot connection 149 from the fixed bracket 148. Upon initial compacting of the sand, the pouring cup pattern 100 creates the desired pouring basin within the cope section of the mold, while the sprue punch 102 creates the intercommunicating sprue passage.

The invention is not to be limited to the exact arrangement of parts shown in the accompanying drawings or described in this specification as various changes in the details of construction may be resorted to without departing from the spirit or scope of the invention. Therefore, only insofar as the invention has particularly been pointed out in the accompanying claims is the same to be limited.

Having thus described the invention what we claim as new and desire to secure by Letters Patent is:

1. In a molding machine of the character described, in combination, an open-ended flask section adapted to receive a charge of loose sand for subsequent compacting thereof about a pattern within the flask section, a first sand-compacting member seated upon and closing one open end of the flask section, a second sand-compacting member movable toward and away from said first sand-compacting member for compacting the loose sand Within the flask section against the first sand-compacting member, there being an opening in said second sand-compacting member, a fixed abutment adjacent to said second sand-compacting member and exteriorly of the flask section, said first sand-compacting member including a pouring cup pattern for creating a pouring depression in the sand during compacting of the latter, a fixed length sprue punch extending between said fixed abutment and said first sand-compacting member and projecting into the flask section slidably through said opening in the second sand-compacting member, said sprue punch being in cooperating engagement with said pouring cup pattern for creating a sprue passage in the sand in communication with the pouring depression during compacting of the sand, means on said pouring cup pattern establishing a seat for the adjacent end of the sprue punch, and a compression spring interposed between the other end of said sprue punch and said fixed abutment to compensate for manufacturing tolerances in the length of the sprue punch and the axial extent of the flask section.

2. In a molding machine of the character described, an open-ended flask section for receiving a charge of loose sand for subsequent compacting thereof within the flask section about a pattern, first and second sand-compacting members, respectively, coaxial with the flask section and mounted for relative movement toward and away from each other in an axial direction for compacting a charge of loose sand Within the flask section, means for effecting relative movement between the first sand-compacting member and the flask section to bring said first sandcompacting member into seating engagement with one open end of the flask section to effectively close said one open end of the flask section, means for moving the second sand-compacting member toward and away from said first sand-compacting member when so seated for sand-compacting and sand-releasing purposes, a pouring cup pattern secured to one of said sand-compacting members for creating a pouring depression .in the charge of sand within the flask section during the compacting opbetween said one end of the punch and the fixed abutment, and cooperating centering means on said first sandcompacting member and the other end of the punch and movable into cooperating relationship when said first sand-compacting member becomes seated upon said one open end of the flask section to center said other end of the punch on the first sand-compacting member and to place the punch under compression between the centering means and said spring.

3. In a molding machine of the character described, in combination, an open-ended flask section for receiving a charge of loose sand for subsequent compacting thereof about a pattern within the flask section, an'imperforate plate designed for seating engagement with one open end of the flask, a squeeze board movable toward and away from the plate for compacting a charge of sand within the flask section, there being an opening through said squeeze board, an abutment exteriorly of the flask section on the side of the squeeze board remote from the plate, a pouring cup pattern secured to the squeeze board and having an axial bore therethrough in register with said opening, a sprue punch interposed between said abutment and the plate and projecting slidably through said opening and bore, and a spring interposed between one 8 end of the punch and the abutment for yieldingly urging "the punch against said plate.

4. In a molding machine of the character described, the combination set forth in claim 3 and including, additionally, cooperating centering means on the plate and adjacent end of the punch.

5. In a molding machine of the character described, the combination set forth in claim 1 and including, additionally, means establishing a lost motion connection between said fixed abutment and the sprue punch whereby the sprue punch and abutment are connected together against separation.

6. In a molding machine of the character described,

the combination set forth in claim 2 and including, additionally, means establishing a lost motion connection'between said fixed abutment and the sprue punch whereby the abutment and sprue punch are connected together against separation.

References Cited by the Examiner UNITED STATES PATENTS 201,377 3/1878 Aiken et a1 2238 632,245 9/1899 Cooper 22-38 1,095,356 5/1914 Riel et a1. 2238 1,905,490 4/1933 Norrick 2238 2,908,951 10/1959 Melka 22-38 FOREIGN PATENTS 609,676 10/ 1948 Great Britain.

MARCUS U. LYONS, Primary Examiner.

MICHAEL V. BRINDISI, Examiner.