US3179295A

US3179295A - Die casting machine gooseneck using air injection with controlled .volume accumulator chamber

Info

Publication number: US3179295A
Authority: US
Publication date: 1965-04-20
Anticipated expiration: 1982-04-20

Description

L. H. MORIN April 20, 1965 3,179,295 DIE CASTING MACHINE GOOSENECK USING AIR INJECTION WITH CONTROLLED .VOLUME ACCUMULATOR CHAMBER Filed June 18, 1962 2 Sheets-Sheet 1 HTTORNEY 3,1 79,295 ION L. H. MORIN April 20, 1965 DIVE CASTING MACHIN E GOOSENECK USING AIR INJECT WITH CONTROLLED VOLUME ACCUMULATOR CHAMBER Filed June 18, 1962 2 Sheets-Sheet 2 INVENTOR Lou/5 H Mom/v This invention relates to the gooseneck structure of die' casting machines,adapting such machinesfor utilizing molten metal having high temperatures and attack, such, for example, as the casting of aluminum. More particularly, the invention deals with-a gooseneckstructure employing materials in at' least part of the volume accumulator of the gooseneck to withstand the temperatures of the molten metal employed while, at the same time,-

assuring positive seal between engagedportions of the different materials. I

Still more particularly, the inventiondeals with a structure of the character described employing compressed air as an operating medium controlling operation of theintake and discharge of metal from the volume accumulator chamber of the gooseneck. The machine illustrated in the drawings is known as a hot chamber pneumatic injection type of casting machine. An insert gas' may be .used as 'the pressure medium inplace of air, if

desirable, because of the nature of the castablematerial.

The novel features'of the invention will be best understood from the followingdescription, when taken together with the accompanying drawings, iii-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. 1 is a diagrammatic sectional view through one form of gooseneck structure whichI employ, with parts of the construction broken away and shown in elevation and schematically illustrating the piping and valves controlling the'corhpressed air supply and exhaust; and

FIG. 2 is an enlarged partial sectional view of a gooseneck structure, generally similar to that shown in FIG. 1, and illustrating a modification.

Whilemy present invention as illustrated in the accompanying drawings -byway of example is desgined primarily for use in die casting metals of relatively high temperatures and attack, such as aluminum, this same approach can, nevertheless, be used in the casting of zinc and other metal alloys commonly known in theart. Further, in addition to utilizing such materials'as titaniumdiboride and titanium nitrogen boron complex to Withstand the temperatures and attack in forming at least part of the volume. accumulator-chamber ofithe' goo'seneck,

utilization of a compressed air. system for discharge of' each shot of the molten metal and the creation of a suckback' in the accumulator chamber results in a quick replenishment of the volume in said chamber, thus enabling a die casting machine of the type and kind under conside-ration to be operated at high speeds in high speed production of the east end products.

Considering now the disclosure in FIG. 1 of the drawing, here I have diagrammaticallyillustrated; in part, at

10 the front plate of adie casting machine and at 11 is shown part of the furnace. shell, insul'ated,-as seen at 12. At 13 I have indicatedI part of the melting pot, Within which the molten metal 14, such for example as art to keep, the metal 14 at the desired temperature;

15: At 16 I have illustrated one formof'gooseneck structure made accordingqtomyinvention, the gooseneck having a long'neck 17, with a passage 18 extending longitudinally therethrough; 'A' suitable nozzle 19 is fixed to A United States Patent" the free end of the neck 17 and has a discharge orifice 20. At 21 I have shown the face view of a die for forming in the cavity 22 thereof a winged nut, diagrammatically illustrated at 23. The gate extending to the cavity 22 is illustrated at 24 and at 25 is showna core pin, upon which the winged nut is formed in providing the hole in said nut. with the gate 24 and adjustments are provided and later described for maintaining this alinement or registration.

Mounted in the lower portion of the gooesneck is a titanium-diboride bushing 26 seating on a shoulder 27 and this bushing is fixed in the gooseneck by heating the lower- The orifice 20 of the nozzle communicatescular valve portion 31 of a valve stem 32 is adapted to seat. The valve stem includes a longitudinal here or port;

33, which opens into the well 28 and controls another; part of the volume accumulator chamber of the goose neck.

The gooseneck includes an upwardly extended stem or sleeve 34, which is open at one side of the lower portion thereof, as clearly illustrated at the right of FIG. 1 of the" drawing. This stem is joined with the neck 17 by a web,

indicated at 35 at theleft of FIG. 1;

The lower end: of the sleeve proper of the stem 34'is internally threaded to receive asplit nut 36 whichfacilitates assemblage of the nut on a valve operating rod 37 supported in thesleeve, the lower end of which is brazed or otherwise secured to the upper end of the valve stem. 32, as in-- dicated at'37'. This valve stem, including its valve por tion 31, is also formed from titanium-diboride in order to Withstand thetemperature and attack of the molten metal employed. The lower end of the rod 37. has an aperture 38 registering withthe bore 33. Said end of the rod has a pipe tapped hole 39 for reception ofa pipe, schematically' illustrated by the line' 40. The operating rod':

37 has,- within. the sleeve 34, a spherical head 41 and between this head and the nut 36 is arranged a compression springr42which tends to. normally move the circular valve 31in "an unseated position with respect to the seat 30 in allowing molten metal to' replenish or refill the v0lume accumulator chamber, as later described. Adjustably supported upon the sleeve portion of the. stem 34. is a bracket43 having a slight swivel movement on apivot 44 for said bracket, this swivel action being in:

timely control in operation of the casting machine in moving the faceof the nozzle 19 into and out of engagement: with-the surface 21 of the die 21. This movement is only essential to break contact'with the die immediately' after the 'shot or'charge of metal into thedie cavity has been completed.

The bracket 43 has an enlarged portion 45, suitably split at a position beyond the section shown in the drawing, for adjustably clamping the bracket on the sleeve, a clamp screw 46 being employed for this purpose. Within the enlarged portion is supported a pinion 47 which has a protruding and'preferably squared end 47', indicated in dotted lines, facilitating rotation of the pinion by a tool, I

the. pinion 47 engaging rack teeth 48'on one surface of the sleeve 34, as diagrammatically illustrated, in controlling adjustment' of the gooseneck for alining 20 with 24,

as previously stated.

The bracket 43 includes a plate portion 49, upon which':

a piston bracket 50 is supported by suitable fastenings 51;

The bracket 50 includes an air cylinder 52, in which a suitably sealed piston 53 is mounted, the piston being diagrammatically shown and omitting .the usual sealing.

means. The piston 53 has a protruding piston rod 54 which operatively engages the head 41 to support the valve 31 in seated position on the bushing 26 against the action of the spring 42. The cylinder 52 has pipe tapped

holes

55 and 56 for receiving'pipes, schematically shown by the

lines

57 and 58, respectively, the pipe 57 admitting air under pressure to the cylinder; Whereas, the pipe 58 controls exhaust of air from the cylinder through a suit-' able valve, schematically shown at 59, for exhaust to atmosphere.

At 60 I have shown at the right of FIG. 1 an air accumulator chamber, having an adjustable screw plunger 61 to control the volume of the chamber consistent with the size of the casting -to be formed, a lock nut 62 being employed to retain 61 in any desired adjusted position. Communicating with the interior of the chamber 60 are three pipe tapped

holes

63, 64 and 65, with which pipes are coupled, the pipes being schematically shown by the

lines

66, 67 and 68, respectively. The pipe 66 communicates with the pipe 40 through a valve, schematically shown at 69. The pipe 67 communicates with a valve 70 open to atmosphere; whereas, the pipe 68 communicates with a valve 71, with which a source of air, under pressure, communicates, this source being generally identified by the lines 72. Also coupled with this source of supply is a valve 73, with which the pipe 57 communicates, the three angularly disposed lines on FIG. 1 of the drawing schematically illustrating this pipe 57 Turning now to the showing in FIG. 2 of the drawing, in this figure, part of the furnace shell, generally similar to the showing in FIG. 1, is indicated at 11' and its insulation is indicated at 12. At 13' is shown part of the melting pot. At 74 is shown a gooseneck, which differs from the gooseneck 16, first, in having a modified lower end 75, with a well 76 formed therein, with which the passage 77 of the neck portion 78 of the gooseneck communicates, the neck portion 78 being generally similar to the neck portion 17 of the gooseneck shown in FIG. 1. The gooseneck 74 is initially made from titanium nitrogen boron complex to withstand the attack of the molten metal.

The gooseneck 74 is further modified in having an upwardly directed shelf extension 79 instead of the integral stem or'sleeve portion 34. Bolted or otherwise secured to this shelf is a bracket portion 80 integral with the lower end of a sleeve portion 81, generally similar to the sleeve portion 34 in FIG. 1 and in the lower internally threaded end of which is arranged a split nut 82, similar to the nut 36. Aside from the above noted changes, the upper structure of thegooseneck shown in FIG. 2 of the drawing will be identical with the structure shown in FIG. 1 and at 43' is shown part of the bracket 43 enveloping the sleeve 81.

With the structure shown in FIG. 2, the'upper surface of the lower portion 75 of the gooseneck has a rounded seat 83, upon which the rounded lower surface 84 of a valve stem 85 operates, this stem being otherwise generally similar to the stem 32 of FIG. 1, the stem including a port 86 registering with the well 76. This stem 85 is also formed of titanium-diboride and has, at its upper end, an enlarged collar portion 87 engaged by a nut 88, which is in threaded engagement with the lower threaded end 89 of an operating rod 90, otherwise, generally similar to the rod 37 of FIG. 1 of the drawing. The threaded end 89 of the rod 90 is partially shown in elevation and part in section in order to clearly illustrate the passage of the collar 87 of 85 into the'nut 88. The nut 88 is utilized in firmly maintaining the upper end of the valve stem 85 in pressure engagement with the lower threaded end 89 of the rod 98. The rod 90 has, at its lower end, a port 91, indicated in dotted lines, which registers with the port 86 of the valve stem 85. At 92 I have indicated in dotted lines the pipe threaded hole, similar to the hole 39. of FIG. 1. With the structure of FIG. 2, it will be 4 apparent that the valve end 84 of the stem 85is held in pressure seated position on 83 by an air actuated piston, similar to 59 of FIG. 1, and that a spring, part of which is shown at 42 in FIG. 2, serves to move the valve stem 85 intoopen or unseated position; In FIG. 2, 86 and 76 control, at least in part, the volume accumulator chamber of the gooseneck. In FIG. 2, the normal level of the molten metal in the pot 13' is indicated at 93, similar to the level of metal, as shown at 14 in FIG. 1 of the drawing. At 93 the normal level of the molten metal of the volume accumulator chamber is illustrated and, in FIG. 1 of the drawing, this is also illustrated at 14'. This condition would take place shortly after a casting has been formed, as at 23, and removed from the die and the die 21 returned to a closed position with the nozzle 19 again moved into abutting engagement with the surface 21',

preparatory for the next successive shot or injection of the molten material into the cavity 22. At a completion of this injection, it will be understood that the level, such as 14' or 93, in the respective goosenecks will drop materially in 33 and possibly in 28 and part of 18 in FIG. 1 or in 86, 76 and part of 77 in FIG. 12, depending upon the required amount of molten metal essential to form the resulting casting in the cavity or cavities of the dies, as at 21, but at no time would all of the metal be discharged through the passages 18 of FIG. 1 or 77 of FIG. 2.

Now, in following through the cycle of operation of the gooseneck, it will be apparent that, prior to the discharge of or shot operation above noted, the valve 71 is closed and the valve 73 is opened, admitting compressed air to the cylinder 52 in actuation of the piston 53 to maintain 31 in seated position'on the bushing 26, the

valves

59, 69 and being closed. Opening of the valve 71 will put a charge of compressed air in the air accumulator chamber 60, after which, this valve 71 will be closed. Then, the valve 69 is opened to admit air under pressure from the chamber 60 into the port 38 to discharge the molten metal from the volume accumulator chamber 33, 28 and possibly part of 18 through the nozzle 19 and into the cavity 22 of the die 21. The valve 70 is promptly opened and this valve will be regulated, so as to provide a controlled suck-back discharge of air through this valve, the valve 70 is closed after the casting shot and the valve 59 opened to permit piston 53 to move up under the urging of spring 42 which will raise valve 31 from seat 30, which will allow the molten metal of the pot to seek its level and flow back into the volume accumulator chamber to the degree of maintaining a level in 33 or 86, as at 14' or 93', consistent with the level of the molten metal in the pot, as at 14 and 93. As a result, a vacuum is created in the nozzle by virtue of the metal level in the passage 18 dropping to the surface, as indicated at 14, resulting in what I term the suck-back.

The suck-back operation starts with the opening of valve '70 which exhausts the air accumulator 60 and reduces pressure in line 40. This permits the level of molten material in valve stem 32 to rise and the level in passage 18 to fall. Then valve 31 is opened to allow equalization of molten material level in respovoir 12, stem 31 and passage 18 as illustrated in FIG. 1. The nozzle 19 is separated from the die 21 only after the suck-back operation and the opening of valve 31.

Thus, and only after the shot, when the nozzle contact is then broken away from the die, namely when the gooseneck swings away on its pivot 44, there can be no nozzle drip which otherwise would drip a glob of metal onto the nozzle face and, when in the next cycle of operation, the nozzle made contact with the die surface, a proper seat could not be obtained. By providing the suck-back, the nozzle face is kept clean, thus insuring continuous uninterrupted cycles of operation of the machine.

By proper control of the valve 70 in governing the exhaust thereof, the suck-back or slight vacuum attained will be controlled in a manner to prevent any rise of molten metal above the level 14' or 93' in the respective goosenecks. Adjustment of 61, as stated, will provide an air accumulator chamber 60 of sufiicient size to store the amount of compressed air necessaryfor discharging the required amount of molten metal to form a predetermined casting, as at 23 in FIG. 1.

In continued operation of a die casting machine incorporating a gooseneck structure as defined, it will be understood that automatic means is provided for replenishment of the molten metal in the pot in, at all times, maintaining a level therein which will keep the volume accumulator chamber at a condition which will at no time permit the full discharge of molten metal as contained end of said neck forming a well in communication with the passage of said neck, said gooseneck having, at the upper portion thereof and in spaced relation to the second named end of the neck, a sleeve, a bracket having means adjustably supporting said sleeve in controlling positioning of said nozzle with respect to the gate of a die structure, said bracket having means for pivotally supporting the same in providing slight movement of the nozzle toward and from a surface of the die structure, a rod mounted in said sleeve, a valve stem coupled with the lower end portion of said rod, the lower end of said valve stem having a substantially spherical endadapted to engage a seat at the upper portion of said well, said valve stem having a port communicating with the well and registering with a port in the lower portion of said rod, the rod having means admitting air into the port thereof, means including a melting pot, in which the lower portion of said gooseneck is arranged for establishing a level of molten metal in the gooseneck and the port of said valve stem at a position below said rod, tensional means within said sleeve operatingly engaging said rod in support of the valve stem in open position with respect to said well, and air operated means mounted in connection with said bracket and operatively engaging said rod for moving the valve stem into seated position against the action of said tensional means.

2. In a die casting machine employing adie structure having a cavity for forming a predetermined product and a gate opening into said cavity and through a surface of the die structure, a gooseneck comprising a long neck having a passage extending therethrough, a melting pot 5 in which said gooseneck is arranged, said pot containing molten metal at predetermined levels in said pot, a nozzle fixed to the upper end of the neck and having an orifice placing the passage of said neck in communication with the gate of said die structure, the upper portion of the gooseneck having a sleeve, a bracket having pivot means controlling movement of said nozzle toward and from the die structure in intermittent casting operations of the machine, means at the lower portion of the neck forming a well, a valve stem of titanium-diboride movable toward and from the well in opening and closing access to the well controlling delivery of molten metal from the pot to said well, said valve stem extending to a position above the'highest level of metal in said pot, means coupled with said valve stem and said bracket controlling movement of the valve stem into open and closed position with respect to said well, said valve stem and part of said last named means having a port opening into said well, means for admitting air under pressure into said port above the level of metal in said pot, said port, well and part of the passage of said neck collectively forming a volume accumulator chamber in which molten metal is positioned, means controlling said last named means for discharge of the metal in said chamber into the cavity of the die structure in forming a casting when said valve stem is in seated position with respect to said well, and said control means comprising an adjustable air accumulator chamber for discharge of metal from said volume accumulator chamber and regulating replenishment of molten metal in said volume accumulator chamber when the valve stem is in open position with respect to said well.

3. In a die casting machine as defined in claim 2, wherein the well portion of said gooseneck comprises a bushing of titanium-diboride press fitted into the lower portion of said neck, and said bushing having a port placing the well of the bushing in communication with the passage of said neck.

4. In a die casting machine as defined in claim 2, wherein said neck and well portion of said gooseneck is formed of titanium nitrogen boron complex.

References Cited by the Examiner UNITED STATES PATENTS 720,714 2/03 Lightbrown 22-70 1,282,963 10/ 18 Shroder 22-69 1,292,679 l/ 19 Bate 22-69 2,609,575 9/52 Morin 22-70 2,872,327 2/ 5 9 Taylor -55 3,019,084 l/ 62 Amstein 23-204 3,123,875 3/64 Madwed 22-70 MICHAEL V. BRINDISI, Primary Examiner.

WILLIAM J. STEPHENSON, Examiner,

Claims

1. A GOOSENECK FOR DIE CASTING MACHINES COMPRISING A LONG NECK HAVING A PASSAGE EXTENDING THERETHROUGH, A NOZZLE AT ONE END OF SAID NECK AND HAVING A DISCHARGE ORIFICE COMMUNICATING WITH SAID PASSAGE, MEANS AT THE OTHER END OF SAID NECK FORMING A WELL IN COMMUNICATION WITH THE PASSAGE OF SAID NECK, SAID GOOSENECK HAVING, AT THE UPPER PORTION THEROF AND IN SPACED RELATION TO THE SECOND NAMED END OF THE NECK, A SLEEVE, A BRACKET HAVING MEANS ADJUSTABLY SUPPORTING SAID SLEEVE IN CONTROLLING POSITIONING OF SAID NOZZLE WITH RESPECT TO THE GATE OF A DIE STRUCTURE, SAID BRACKET HAVING MEANS FOR PIVOTALLY SUPPORTING THE SAME IN PROVIDING SLIGHT MOVEMENT OF THE NOZZLE TOWARD AND FROM A SURFACE OF THE DIE STRUCTURE, A ROD MOUNTED IN SAID SLEEVE, A VALVE STEM COUPLED WITH THE LOWER END PORTION OF SAID ROD, THE LOWER END OF SAID VALVE STEM HAVING A SUBSTANTIALLY SPHERICAL END ADAPTED TO ENGAGE A SEAT AT THE UPPER PORTION OF SAID WELL, SAID VALVE STEM HAVING A PORT COMMUNICATING WITH THE WELL AND REGISTERING WIT A PORT IN THE LOWER PORTION OF SAID ROD, THE ROD HAVING MEANS ADMITTING AIR INTO THE PORT THEREOF, MEANS INCLUDING A MELTING POT, IN WHICH THE LOWER PORTION OF SAID GOOSENECK IS ARRANGED FOR ESTABLISHING A LEVEL OF MOLTEN METAL IN THE GOOSENECK AND THE PORT OF SAID VALVE STEM AT A POSITION BELOW SAID ROD, TENSIONAL MEANS WITHIN SAID SLEEVE OPERATINGLY ENGAGING SAID ROD IN SUPPORT OF THE VALVE STEM IN OPEN POSITION WITH RESPECT TO SAID WELL, AND AIR OPERATED MEANS MOUNTED IN CONNECTION WITH SAID BRACKET AND OPERATIVELY ENGAGING SAID ROD FOR MOVING THE VALVE STEM INTO SEATED POSITION AGAINST THE ACTION OF SAID TENSIONAL MEANS.