U.S. patent application number 10/790472 was filed with the patent office on 2005-09-01 for hot chamber die casting.
Invention is credited to Jones, Melvin A..
Application Number | 20050189085 10/790472 |
Document ID | / |
Family ID | 34887481 |
Filed Date | 2005-09-01 |
United States Patent
Application |
20050189085 |
Kind Code |
A1 |
Jones, Melvin A. |
September 1, 2005 |
HOT CHAMBER DIE CASTING
Abstract
This assembly is for use with hot chamber die casting. More
specifically, the assembly is a fast fill bottom fill gooseneck.
The intake port has been moved to the bottom of the gooseneck. The
bottom intake port has been fitted with an interior plug. When the
plunger moves upwardly, it creates a vacuum the pulls the interior
plug upwardly. This vacuum also opens the bottom intake port
pulling molten metal into the chamber from the reservoir. When the
plunger moves downwardly, the interior plug moves downwardly and
seals the bottom intake port. As the plunger continues to travel
downward, it pressurizes the molten metal and forces the molten
metal contained in the cylinder through the channel in the
gooseneck, through the nozzle seat and the nozzle into the die
cavity of the die thereby filling the cavity and forming the cast
part.
Inventors: |
Jones, Melvin A.; (Tiffin,
OH) |
Correspondence
Address: |
EMCH, SCHAFFER, SCHAUB & PORCELLO CO
P O BOX 916
ONE SEAGATE SUITE 1980
TOLEDO
OH
43697
|
Family ID: |
34887481 |
Appl. No.: |
10/790472 |
Filed: |
March 1, 2004 |
Current U.S.
Class: |
164/113 ;
164/316 |
Current CPC
Class: |
B22D 17/04 20130101 |
Class at
Publication: |
164/113 ;
164/316 |
International
Class: |
B22D 017/04 |
Claims
1. An assembly for use with hot chamber die casting comprising a
gooseneck assembly having a channel extending therethrough, wherein
the gooseneck assembly has an exterior surface, an interior surface
and a bottom; wherein the interior surface defines the channel
extending therethrough; a plunger matingly engaging the channel; a
bottom intake port located in the bottom of the gooseneck wherein
the bottom port includes a passageway extending from the exterior
surface to the interior surface of the gooseneck; and a plug
assembly housed by the bottom intake port; wherein the passageway
of the bottom port is open when the plug assembly is in an upper
position and the passageway is closed when the plug assembly is in
a lower position wherein the plug assembly includes an interior
plug and a shaft wherein the interior plug is adjacent the interior
surface of the bottom of the gooseneck and wherein the passageway
of the bottom port houses the shaft of the plug assembly.
2. (canceled)
3. An assembly according to claim 1 wherein the shaft of the plug
assembly extends beyond the exterior surface of the bottom of the
gooseneck.
4. An assembly according to claim 1 wherein the plug assembly
includes an exterior plug attached to the shaft adjacent the
exterior surface of the bottom of the gooseneck.
5. An assembly according to claim 4 wherein the exterior plug of
the assembly includes at least one aperture therethrough.
6. An assembly according to claim 4 wherein the exterior plug of
the assembly includes a plurality of apertures therethrough.
7. An assembly according to claim 1 including molten metal
reservoir containing molten metal wherein the gooseneck assembly is
partially submerged in the molten metal of the reservoir.
8. An assembly according to claim 1 wherein the interior surface of
the gooseneck assembly includes a recess adjacent the passageway of
the bottom port and wherein the recess houses the interior plug
when the plug is in a lower position.
9. An assembly for use with hot chamber die casting comprising a
gooseneck assembly having a channel extending therethrough, wherein
the gooseneck assembly has an exterior surface, an interior surface
and a bottom; wherein the interior surface defines the channel
extending therethrough; a plunger matingly engaging the channel; a
bottom intake port located in the bottom of the gooseneck wherein
the bottom port includes a passageway extending from the exterior
surface to the interior surface of the gooseneck; and a plug
assembly housed by the bottom intake port; wherein the passageway
of the bottom port is open when the plug assembly is in an upper
position and the passageway is closed when the plug assembly is in
a lower position wherein the plug assembly is a ball bearing and
wherein the interior surface of the gooseneck assembly includes a
recess adjacent the passageway of the bottom port wherein the
recess houses the ball bearing when the ball bearing is in a lower
position.
10. An assembly according to claim 9 wherein the plunger has a
bottom surface, wherein the bottom surface has a recess and wherein
the recess of the plunger houses the ball bearing when the ball
bearing is in an upward position.
11. An assembly according to claim 1 wherein a sleeve lines the
interior surface defining the channel extending through the
gooseneck.
12. An assembly according to claim 11 wherein the sleeve has a
bottom, wherein the bottom of the sleeve has a bottom intake port
and wherein the port of the bottom of the sleeve includes a
passageway extending from the exterior surface to the interior of
the gooseneck; and wherein the plug assembly is housed by the
bottom intake port of the sleeve and wherein the passageway of the
bottom port of the sleeve is open when the plug assembly is in an
upper position and the passageway is closed when the plug assembly
is in a lower position.
13. An assembly according to claim 12 wherein the plug assembly
includes an exterior plug attached to the shaft adjacent the
exterior surface of the bottom of the gooseneck, wherein the
exterior plug is a strainer.
14. A method for hot chamber die casting comprising the steps of:
providing a gooseneck assembly having a channel extending
therethrough, wherein the gooseneck assembly has an exterior
surface, an interior surface and a bottom; providing a plunger
matingly engaging the chamber, providing a bottom intake port
having a passageway in the bottom of the gooseneck assembly
extending from the exterior surface to the interior surface of the
bottom of the gooseneck assembly, providing a plug assembly
adjacent the bottom port, causing the plunger to move in an upward
direction and simultaneously causing the plug assembly to move
upwardly and open the passageway of the bottom port, housing the
plug assembly in the bottom intake port, including an interior plug
and a shaft in the plug assembly locating the interior plug
adjacent the interior surface of the bottom of the gooseneck, and
housing the shaft of the plug assembly in the passageway of the
bottom port.
15. A method according to claim 14 including the steps of: causing
the plunger to move in a downward direction and simultaneously
causing the plug assembly to move in a downwardly direction closing
the passageway of the bottom port.
16. A method according to claim 15 including the steps of:
providing a molten metal reservoir containing molten metal; and
partially submerging the bottom of the gooseneck assembly in the
molten metal of the reservoir.
17. A method according to claim 16 wherein the step of moving the
plug assembly in a downward direction seals off the chamber from
the reservoir.
18. A method according to claim 17 including the steps of
continuing to move the plunger in downwardly direction, forcing the
molten metal in the cylinder through the channel of the gooseneck,
through a nozzle seal and through a nozzle into a die cavity,
filling the die cavity and forming a cast part in the die
cavity.
19. A method according to claim 14 wherein the step of causing the
plunger to move in an upward direction creates a vacuum that pulls
the plug assembly upward.
20. A method according to, claim 16 wherein the step of causing the
plunger to move in an upward direction creates a vacuum that pulls
the plug assembly upwardly and wherein the vacuum also pulls molten
metal from the reservoir through the bottom intake port into the
chamber.
21. A method according to claim 20 wherein the molten metal in the
reservoir has a weight that creates a head of pressure wherein the
head of pressure pushes molten metal from the reservoir through the
bottom intake port into the chamber when the plug assembly moves
upwardly and opens the passageway of the bottom intake port.
22. A method according to claim 14 including including the step of
lining the interior surface defining the channel through the
gooseneck with a sleeve.
23. A method according to claim 22 wherein the sleeve has a bottom
and including the step of providing a bottom intake port in the
bottom of the sleeve.
24. A method according to claim 23 including the step of providing
the bottom intake port of the sleeve with a passageway extending
from the surface to the interior of the gooseneck.
25. A method according to claim 24 including the step of the bottom
intake port of the sleeve housing the plug assembly.
26. A method according to claim 25 including the step of providing
the plug assembly with an exterior plug wherein the exterior plug
is a strainer.
27. A method according to claim 26 including the step of straining
molten metal entering the gooseneck through the strainer.
Description
TECHNICAL FIELD OF THE INVENTION
[0001] This invention relates to an assembly for use with hot
chamber die casting. More specifically, the assembly includes a
bottom fill gooseneck.
BACKGROUND OF THE INVENTION
[0002] Die casting machines generally utilize one of two
classifications of casting material pumping systems, either a hot
chamber system or a cold chamber system. Hot material chamber die
casting machines include parts that are partially submerged in a
vat containing the molten metal and thus operate at the temperature
of the metal bath. Cold chamber die casting machines are unheated
except for the die member which receives the molten metal during
the casting process. Hot chamber systems are used primarily for the
casting of metals having low melting points such as tin, zinc and
lead alloys. Cold chamber machines can be used for die casting most
metals, however, they are most commonly used for aluminum,
magnesium and copper alloys.
[0003] The industry has lavished great care in choosing materials
for the construction of hot chamber die casting machines. Improved
materials for the various parts have led to enhanced resistance
against wear, hardening and softening. The industry, however, has
had little success in overcoming failure problems resulting from
the high operating pressures present in the hot melt die casting
process.
[0004] A recent, major improvement in the industry has been a
reinforced casting. Specifically, the improvement is a reinforced
gooseneck and reinforced components for use with a hot chamber die
casting machine. The improvement provides for the reinforcement of
the gooseneck, nozzle, and nozzle seat. The preferred embodiment
focuses on reinforcing the gooseneck as this is the location where
most pressure-caused failures occur. See U.S. Pat. No. 6,481,489
issued to Melvin A. Jones which is herein incorporated by
reference.
[0005] Another problem has been communication between the pressure
cylinder of the gooseneck and the molten metal reservoir. Various
attempts have been made to fast fill the chamber of the gooseneck
or to more completely reach the bottom of the reservoir of molten
material. U.S. Pat. No. 4,261,414 discloses a complicated mechanism
for rapidly providing molten metal to a die casting machines. This
patent discloses a double toggle arrangement including a bell crank
pivotally mounted on a yoke. The patent also discloses a double
shaft arrangement for filling the chamber of the gooseneck. Shaft
104 operates gate valve 100. Gate valve 100 has two apertures.
Aperture 112 provides communication between pump chamber 96 and pot
32. Aperture 114 provides communication between chamber 96 and
nozzle 54. Shaft 108 operates pump 110 mounted in chamber 96.
Movement of shafts 104 and 108 operate in sync to fill and drain
chamber 96 through apertures 112 and 114. Obviously, keeping the
shafts in sync would be difficult. While this system may function,
it cannot be retrofitted to an existing gooseneck assembly.
Maintenance also would be difficult.
BRIEF SUMMARY OF THE INVENTION
[0006] I have invented a fast fill assembly that can be retrofitted
to an existing gooseneck assembly. In a conventional gooseneck
assembly, the intake port typically fills the chamber from the
side. See intake post 30 in FIG. 1 of my U.S. Pat. No. 6,481,489. I
have moved the intake port to the bottom wall of the gooseneck. I
also have fitted the bottom intake port with an interior plug. When
the plunger moves upwardly, it creates a vacuum the pulls the
interior plug upwardly. The vacuum created by the upwardly moving
plunger also pulls or sucks molten metal from the lower portion of
the reservoir through the bottom intake port into the chamber. The
head of pressure created by the weight of molten metal also forces
the molten metal through the open bottom intake port into the
chamber. When the plunger moves downwardly, the interior plug moves
downwardly and seals the bottom intake port. The interior plug
includes a shaft that extends downwardly through the bottom intake
port. Preferably, the shaft of the plug includes an exterior plug
that prevents the interior plug from loosing communication with the
bottom intake port.
[0007] The gooseneck and pressure cylinder are partially submerged
in the reservoir of molten non-ferrous metal. The intake port
provides a passageway between the pressure cylinder and the
reservoir. With the plunger in the up position, molten metal is
free to flow from the reservoir through the intake port and into
the pressure cylinder. When the plunger is moved downward, it seals
off the pressure cylinder from the reservoir. As the plunger
continues to travel downward, it pressurizes the molten metal and
forces the molten metal contained in the cylinder through the
channel in the gooseneck, through the nozzle seat and the nozzle
into the die cavity of the die thereby filling the cavity and
forming the cast part.
[0008] Other objects and advantages of the present invention will
become apparent to those skilled in the art upon a review of the
following detailed description of the preferred embodiments and the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a cross-sectional side elevational view of a die
casting machine and die according to the present invention with the
plug in the down position.
[0010] FIG. 2 is a cross-sectional view of FIG. 1 with the plug
assembly in the up position.
[0011] FIG. 3 is a partially exploded view showing a recess for the
plug assembly.
[0012] FIG. 4 shows the exterior plug of the plug assembly in
greater detail.
[0013] FIG. 5 is a cross-sectional view of FIG. 1 showing the plug
assembly without the exterior plug.
[0014] FIG. 6 is a partially exploded view showing a plug assembly
which is a ball bearing.
[0015] FIG. 7 is a partially exploded view showing a sleeve with
the plug assembly in the sleeve.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0016] This assembly for use with hot chamber die casting comprises
a gooseneck assembly having a channel extending therethrough,
wherein the gooseneck assembly is made from a ferrous material. The
gooseneck assembly has an exterior surface, an interior surface and
an interior located between the exterior and interior surfaces. The
interior surface defines the channel extending therethrough. U.S.
Pat. No. 6,481,489 discloses an embodiment where reinforcing
members are located in the interior of the gooseneck assembly.
[0017] FIG. 1 shows a hot chamber die casting machine having a
submerged plunger mechanism, a gooseneck and a nozzle. Machine 12
consists of molten metal reservoir 18, plunger 20, pressure
cylinder 22, gooseneck 24, nozzle seat 26 and nozzle 10. Nozzle 10
is designed to matingly engage with die cavity 28 of die 16 so that
molten metal 14 is received into die cavity 28 from the machine
operation.
[0018] Gooseneck 24 and pressure cylinder 22 are partially
submerged in reservoir 18 of molten non-ferrous metal 14. Bottom
intake port 30 provides a passageway between pressure cylinder 22
and reservoir 18. With plunger 20 in the up position (as shown in
FIG. 2), molten metal 14 is pulled or forced from reservoir 18
through intake port 30 and into pressure cylinder 22. When plunger
20 is moved downward (as shown in FIG. 1), plug assembly 40 seals
off pressure cylinder 22 from reservoir 18 as shown in FIG. 2. As
plunger 20 continues to travel downward, it pressurizes molten
metal 14 and forces molten metal 14 container in cylinder 22
through channel 32 in gooseneck 24, through nozzle seat 26 and
nozzle 10, into die cavity 28 of die 16, thereby filling the cavity
and forming the cast part.
[0019] After the metal has solidified in die cavity 28, plunger 20
is retracted, thereby uncovering intake port 30 and molten metal
again is pulled and forced from reservoir 18 into pressure cylinder
22, thus readying machine 12 for the next cycle.
[0020] FIG. 1 shows plug assembly 40 in the downward position. Plug
42 matingly engages interior surface 46 of cylinder 22 and seals
off cylinder 22 from reservoir 18.
[0021] FIG. 2 shows plug assembly 40 in the up position. Bottom
intake port houses (30) plug assembly 40. When plunger 20 is in the
up position, plug assembly 40 is in the up position. This provides
a passageway between pressure cylinder 22 and reservoir 18. Thus,
molten metal 14 is pulled from reservoir 18 through bottom intake
port 30 into cylinder 22. When plunger 20 is down, plug assembly 40
is down. This seals off cylinder 22 from reservoir 18.
[0022] Plug assembly 40 includes interior plug 42 and shaft 44.
Bottom intake port 30 houses shaft 44. Preferably shaft 44 is
longer than port 30 and smaller than port 30. Typically port 30 and
shaft 44 have a circular cross-section and shaft 44 has a smaller
diameter in order to allow molten metal to flow when the assembly
40 is in the up position. The longer length of shaft 44 prevents
assembly 40 from being pulled completely out of port 30 into
cylinder 22.
[0023] FIG. 3 is a partially exploded view showing recess 50 in
interior surface 46. Recess 50 houses plug 42 and circumscribes
opening 54 of passageway 56 of port 30. Recess 50 preferably
enhances the ability of plug 42 to mating engage interior surface
46 and and seal off cylinder 22 from reservoir 18.
[0024] FIG. 3 and FIG. 4 shows an embodiment wherein plug assembly
50 including exterior plug 60. Exterior plug 60 engages exterior
surface 62 of gooseneck 24 when assembly 40 is in the up position
and molten metal is filing cylinder 22. Exterior plug 60 includes
at least one aperture 66 therein. Aperture 66 allows molten metal
14 to flow into cylinder 22 through passageway 56. Preferably
aperture 66 is a plurality of apertures.
[0025] FIG. 5 shows plug assembly 40 with interior plug 42 and
shaft 44, but without exterior plug 60. Shaft 44 is longer than
port 30. The longer length of shaft 44 prevents assembly 40 from
being pulled completely out of port 30 into cylinder 22.
[0026] FIG. 6 shows an embodiment wherein assembly 40 is a ball
bearing. Preferably recess 50 is used when assembly 40 is a ball
bearing. In this embodiment, bottom surface 70 of plunger 20
includes recess 72. Recess 72 matingly engages ball bearing 40 when
plunger 20 is in the down position.
[0027] FIG. 7 is a partially exploded view showing a sleeve with
the plug assembly in the bottom of the sleeve. FIG. 7 shows sleeve
80 extending to the bottom of cylinder 22. Sleeve 80 includes
sleeve bottom 82 and sleeve port 84. Port 84 houses plug assembly
86 when assembly 40 is in a downward position. Preferably port 84
includes recess 88. Plug assembly 86 includes strainer 90. Plug
assembly 86 moves upwardly and downwardly in much the same fashion
as does plug assembly 40. Sleeve 80 may be made of grey iron,
steel, alloyed steel and the like.
[0028] Strainer 90 is similar to exterior plug 60 of FIG. 4 except
strainer 90 has a multiplicity of apertures 66. In one embodiment
strainer 90 is made of a mesh material.
[0029] The process and apparatus of this invention provides for a
simpler and faster operation with more shots per hour. Strainer 90
enables cleaner metal into chamber 22. The cleaner molten metal
allows for longer sleeve, plug and plunger life. The bottom fill
provides a higher and more constant temperature for the molten
metal than the traditional top fill arrangements. Bottom fill also
reduces or eliminates dross from entering the cylinder. Dross is
oxidized molten metal typically found at the top of a molten metal
reservoir such as reservoir 18. Dross is a contaminant to the
gooseneck and cylinder and shortens the life of the apparatus.
[0030] The weight of molten metal 14 in reservoir 18 provides head
of pressure necessary to push molten metal 14 from reservoir 18
through bottom intake post 30 into pressure cylinder 22 when
plunger 20 moves upwardly. The head of pressure works with the
vacuum created by upwardly moving plunger 20 to fill cylinder 22.
In a conventional gooseneck assembly, the intake post typically
fills the cylinder from the side near the top of the reservoir. The
pressure head near the top of the reservoir pot has little or no
head of pressure. Bottom filling provides a more efficient,
economical and faster drawing of molten metal from the reservoir
(pot).
[0031] The term "gooseneck" is not to be constructed as meaning "in
the shape of a goosenek", but merely an arrangement with a similar
function and providing a duct channel or bore for the molten metal
to be injected from the cylinder, upwards alongside the cylinder
and laterally to a die.
[0032] The above description of the invention and the alternative
embodiments is intended to be illustrative of the invention as a
whole and not limiting up [on the scope of the following claims. It
is envisioned that the reinforcing members may be incorporated into
any cast member who is exposed to internal pressure and subject to
bursting and failure as a result of the pressures.
[0033] The above detailed description of the present invention is
given for explanatory purposes. It will be apparent to those
skilled in the art that numerous changes and modifications can be
made without departing from the scope of the invention.
Accordingly, the whole of the foregoing description is to be
construed in an illustrative and not a limitative sense, the scope
of the invention being defined solely by the appended claims.
* * * * *