Note: Descriptions are shown in the official language in which they were submitted.
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INJECTOR UNIT OF INJECTION-MOLDING SYSTEM
TECHNICAL FIELD
The present invention generally relates to, but is not limited to, molding
systems, and more
specifically the present invention relates to, but is not limited to, (i) an
injector unit, (ii) an injection-
molding system having an injector unit.
BACKGROUND OF THE INVENTION
Examples of known molding systems are (amongst others): (i) the HyPET
(trademark) Molding
System, (ii) the Quadloc (trademark) Molding System, (iii) the Hylectric
(trademark) Molding
System, and (iv) the HyMET (trademark) Molding System, all manufactured by
Husky Injection
Molding Systems (Location: Canada; www.husky.ca).
HUSKYS's 180 to 825 Ton Machines sales brochure dated May 1994 from page 1 to
3) explains the
"Moduline" approach to assembling injection molding machines (including
injection units) from a
variety of alternate prefabricated sub-assemblies.
United States Patent Number 4,615,669 (Inventor: FUJITA et al; Published: 1986-
10-07) discloses an
injection apparatus of an injection molding machine that includes a heating
cylinder and a screw
disposed in the heating cylinder, and the screw is axially moved and rotated
in the heating cylinder
for plasticizing the molten material by mechanisms or devices assembled in the
injection apparatus,
which is driven by electric drive means through driving power transmission
means. The electric drive
means comprises two servomotors and the power transmission means comprises two
power
transmission mechanisms operatively connected to the servomotors respectively
so that one of the
two servomotors drives a mechanism for axially moving the screw through one of
the two power
transmission mechanisms and the other of the two servomotors drives a
mechanism for rotating the
screw through the other of the two power transmission mechanisms, parallelly
or concurrently.
United States Patent Number 5,417,558 (Inventor: HEINDEL et al.; Published
1995-05-23) discloses
an injection molding unit for injection molding machines, which includes a
first subassembly having
a plasticizing unit including a screw cylinder and a screw, a second
subassembly having a metering
drive to rotate the screw of the plasticizing unit, a third subassembly having
two drives with
substantially parallel axes for providing motion of the screw cylinder
relative to an injection mold,
and a fourth subassembly having two drives with substantially parallel axes
for producing actual
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displacement of the screw in the screw cylinder of the plasticizing unit, with
the plasticizing unit
being located substantially centrally between the two parallel axes of the
third and fourth
subassembly drives. The two drives of said fourth subassembly include two
liquid-cooled electric
servomotors, respectively, electrically connected to one another to operate
synchronously.
United States Patent Number 5,645,873 (Inventor: CARTER; Published: 1997-07-
08) discloses an
accumulator head for a blow molding machine uses an electromechanical drive
assembly for the
purging and programming functions. The purging actuator of the drive assembly
includes a ball screw
and nut assembly in which the ball screw is rotated by an electric motor to
move the ball nut
assembly vertically and operate the plunger of the accumulator. A second ball
screw and nut
assembly is included in the programming actuator of the drive assembly for
moving the mandrel
vertically, thereby controlling the size of the die outlet opening of the
accumulator. Preferably, the
ball screws of the programming and purging actuators are axially aligned with
the nut assemblies
each carried by a yoke that travels on guide rods. Four support rods are
provided to maintain
alignment and provide stationary mounting for the respective motors. The
structure has sufficient
rigidity to supply the force required for the purging operation, but uses no
hydraulic actuators.
United States Patent Number 5,968,563 (Inventor: HEHL; Published: 1999-10-19)
discloses injection
molding unit for a plastics injection-molding machine for processing
plastifiable materials, which
includes a plasticizing unit for supplying plastifiable material to a mold via
a nozzle along an
injection axis. The plasticizing unit receives a feeding mechanism and the
plasticizing unit is
detachably received in a carrier block. The feeding mechanism is mounted at an
injection bridge
which is movable toward and away from the carrier block for movement of the
feeding mechanism
relative to the plasticizing unit. A plurality of electromechanical drive
units are arranged
symmetrically to the injection axis for displacement of the injection molding
unit along the injection
axis for attachment of the nozzle to the mold. A plurality of
electromechanical injection units are
arranged symmetrically to the injection axis for movement of the injection
bridge relative to the
carrier block. The carrier block and injection bridge are displaceable along
linear guiding elements.
The linear guiding elements are arranged symmetrically to the injection axis
and the drive units, the
injection units and the linear guiding elements lie in different planes each
of which include the
injection axis.
United States Patent Number 5,974,948 (Inventor: THOMPSON et al.; Published:
1999-11-02)
discloses a piston and cylinder assembly for use in actuating a locating pin
for sheet metal, which
provides stability for a pin mounted thereon against side to side movement and
rotation. To this end
the assembly includes a cylinder body assembly with an internal bore and a
piston axially slidable
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within the bore. A piston rod is connected with the piston, and the rod has a
free end for connection
of a sheet metal locating pin. A first guide surface is formed within the
cylinder body assembly and a
second guide surface is formed on one of the piston and piston rod, the first
and second guide
surfaces cooperating to prevent rotation of the piston and piston rod as the
piston and piston rod slide
axially with respect to the cylinder body assembly. The first and second guide
surfaces preferably are
internal and external splines. First and second bearings are connected to the
cylinder body assembly
and support the piston rod for straight line movement. The first and second
bearings being located on
opposite sides of the piston. One of the bearings may be the splines.
United States Patent Number 6,068,810 (Inventor: KESTLE et al.; Published:
2000-05-30) discloses
a plasticizing unit having a plasticizing screw, an injection piston connected
to the screw, a quill
connected to the piston, and hydraulic cavity formed by the piston and a quill
end face. Hydraulic
fluid is transferred to the hydraulic cavity to move the piston and screw away
from the quill. The
screw and piston are subsequently moved towards the quill to displace
hydraulic fluid out of the
hydraulic cavity and cause back pressure. The back pressure is counteracted by
acting on the back of
the quill.
United States Patent Number 6,136,246 (Inventor: RAUWENDAAL et al.; Published:
2000-10-24)
discloses a screw extruder having a barrel which has a bore defining an inner
surface and one or more
extruder screws, positioned within the bore. The extruder screw or screws
include a central shaft and
one or more screw flights. The extruder screw or screws further including one
or more dispersive
mixing elements, which interact with the inner surface of the barrel to form
one or more progressively
narrowing passages through which material is. forced into multiple regions of
high elongational and
shear stress. A second preferred embodiment is a screw extruder having a
barrel having a bore
defining an inner surface and one or more extruder screws, positioned within
the bore. The extruder
screw or screws include a central shaft and a number of dispersive mixing
elements, which are
configured and positioned to form a number of progressively narrowing passages
through which
material is forced into multiple regions of high elongational and shear
stress.
United States Patent Number 6,241,504 (Inventor: FRECHINGER; Published: 2001-
06-05) discloses
an injection unit for an injection molding machine, with a housing carrying a
plasticizing cylinder and
with a transverse support arranged movably in the housing, which support is
connected to a
plasticizing screw mounted in a rotatable and longitudinally displaceable
manner in the plasticizing
cylinder, wherein piston rods projecting on both sides in the longitudinal
direction of the injection
unit are connected to the transverse member, the free ends of which each enter
into a cylinder
chamber in the manner of plungers.
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United States Patent Number 6,394,780 (Inventor: HEHL; Published: 2002-05-28)
discloses an
injection molding unit for an injection molding machine, which includes two
electric drives provided
as electromechanical injection unit and electromechanical dosing unit, the
axis of which are aligned
with the axis of injection. A compact injection molding unit that is easy to
assemble and maintain is
achieved due to the fact that the first and second electric drives are
disposed on the injection bridge
on both sides of a separating plane that extends substantially crosswise to
the axis of injection and
separates the area of influence of the first electric drive from the area of
influence of the second
electric drive.
United States Patent Number 6,517,335 (Inventor: LONG et al; Published: 2003-
02-11) discloses an
apparatus for dewatering a slurry of elastomeric polymer and water, using an
extruder or extruders
provided with a device for measuring an actual water content of the elastomer
at a position within the
extruder or extruders, and a control system for controlling the moisture
content of elastomeric
polymer exiting the extruder or extruders through an exit die based, at least
in part, on the measured
water content.
United States Patent Number 6,835,057 (Inventor: KNAUFF et al; Published: 2004-
12-28) discloses
an injection unit for an injection-molding machine for processing
thermoplastic material is designed
in such a way that a direct drive which meets high dynamic requirements is
used for the injection
operation and that a standard motor, the rotational speed of which is
optimized to the material
preparation process by a gear mechanism, is used for the material preparation,
in which such dynamic
requirements do not exist.
United States Patent Application Number 2005/0048162 (Inventor: TENG et al.;
Published: 2005-03-
03) discloses a drive assembly for rotating and translating a shaft comprising
a hollow shaft motor
and a fluid cylinder. The hollow shaft motor rotates the shaft and the fluid
cylinder moves the shaft
lengthwise. The drive is particularly useful in the injection unit of an
injection-molding machine. In
one preferred embodiment the injection unit includes a hollow electric motor
and a hydraulic
cylinder. A first cylinder wall of the hydraulic cylinder is joined to a rotor
of the hollow motor. A
second cylinder wall of the cylinder is connected to a stationary portion of
the hollow motor. A piston
has two end portions. One end portion of the piston engages the first cylinder
wall and the other end
portion of the piston engages the second cylinder wall. Means for rotating the
piston are attached to
the rotor. The means for rotating also permits the piston end portions to
slide along the cylinder walls.
One channel means provides hydraulic fluid to drive the piston in a forward
direction and another
channel means provides hydraulic fluid to drive the piston in a reverse
direction. Means are provided
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for attaching an injection screw to the piston. In the preferred arrangement,
the cylinder is at least
partially situated within the hollow motor.
United States Patent Number 7,033,158 (Inventor: BECKER et al.; Published:
2006-04-25) discloses
an injection screw that is rotationally driven by a rotating motor having a
stator and a rotor and can be
moved by a number of electrical linear motors, linear motor comprising a
primary part, which
functions as a stator, and a secondary part, which is linearly movable in the
axial direction in a screw
cylinder to execute the injection function. The primary parts are assembled to
form a first housing-
like unit and the secondary parts are assembled to form a second housing-like
unit which is coupled
to the screw for drive purposes. The rotating motor, fixedly connected to the
screw in the axial
direction, is arranged with its stator fixedly coupled in the axial direction
to the secondary housing-
like unit.
United States Patent Application Number 2006/0134264 (Inventor: HAHN;
Published: 2006-06-22)
discloses a screw for injection molding that provides a coaxial piston that
allows an effective cross-
sectional area of the screw to be varied during an injection cycle, which
permits small shot metering
with relatively large diameter injection molding screws.
United States Patent Application Number 2007/0069425 (Inventor: KLAUS;
Published: 2007-03-29)
discloses an apparatus for injection molding that includes an injection unit
having a plunger. The
plunger is translated with accumulation of plasticized material in preparation
for injection and is
advanced to inject the accumulated plasticized material into mold cavities. At
least one electric motor
is engaged with the plunger to resist translation as melt is accumulated and
to inject plasticized
material into the mold cavities. At least one hydraulic actuator selectably
operates the plunger during
a pack and hold interval to supply supplemental force when force supplied by
the electric motors is
limited to maintain the operation of the motors within the applicable
continuous duty rating thereof.
The electric motors are advantageously selectably operatively engaged with the
plunger to inject
plasticized material into the mold cavities and the hydraulic actuators are
operated to inject
plasticized material into the mold cavities when the motors are not engaged.
SUMMARY OF THE INVENTION
According to a first aspect of the present invention, there is provided an
injector unit (100) including
a screw-drive unit (101). The screw-drive unit (101) has (i) a prefabricated
screw-rotation actuator
(102A) that is selected from a group (104) that has prefabricated screw-
rotation actuators (102A;
102B; 102C). The screw-drive unit (101) also includes a prefabricated screw-
translation actuator
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(106A) that is selected from a collection (108) that has prefabricated screw-
translation actuators
(106A; 106B; 106C). The prefabricated screw-translation actuators (106A; 106B;
106C) are
cooperative with at least one of the prefabricated screw-rotation actuators
(102A; 102B; 102C).
According to a second aspect of the present invention, there is provided an
injection-molding system
having an injector unit (100) including a screw-drive unit (101). The screw-
drive unit (101) has (i) a
prefabricated screw-rotation actuator (102A) that is selected from a group
(104) that has prefabricated
screw-rotation actuators (102A; 102B; 102C). The screw-drive unit (101) also
includes a
prefabricated screw-translation actuator (106A) that is selected from a
collection (108) that has
prefabricated screw-translation actuators (106A; 106B; 106C). The
prefabricated screw-translation
actuators (106A; 106B; 106C) are cooperative with at least one of the
prefabricated screw-rotation
actuators (102A; 102B; 102C).
A technical effect, amongst other technical effects, of the aspects of the
present invention is improved
cost-effectiveness associated with manufacturing injection units associated
with injection-molding
systems.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the non-limiting embodiments of the present
invention (including
alternatives and/or variations thereof) may be obtained with reference to the
detailed description of
the non-limiting embodiments along with the following drawings, in which:
FIGS. IA and 1B depict schematic representations of an injector unit according
to a first non-
limiting embodiment;
FIG. 2 depicts a schematic representation of the injector unit 100 according
to a second non-
limiting embodiment;
FIG. 3 depicts a schematic representation of the injector unit 100 according
to a third non-
limiting embodiment;
FIG. 4 depicts a schematic representation of the injector unit 100 according
to a fourth non-
limiting embodiment;
FIG. 5 depicts another schematic representation of the injector unit 100
according to the
fourth non-limiting embodiment;
FIG. 6 depicts a schematic representation of the injector unit 100 according
to a fifth non-
limiting embodiment;
FIG. 7 depicts another schematic representation of the injector unit 100
according to the fifth
non-limiting embodiment;
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FIG. 8 depicts a schematic representation of the injector unit 100 according
to a sixth non-
limiting embodiment;
FIG. 9 depicts a schematic representation of the injector unit 100 according
to a seventh non-
limiting embodiment;
FIGS. 10 to 13 depict perspective views of the injector unit 100 according to
the second non-
limiting embodiment depicted in FIG. 2; and
FIGS. 14 and 15 depict cross sectional views of the injector, unit 100
according to an eighth
non-limiting embodiment.
The drawings are not necessarily to scale and are sometimes illustrated by
phantom lines,
diagrammatic representations and fragmentary views. In certain instances,
details that are not
necessary for an understanding of the embodiments or that render other details
difficult to perceive
may have been omitted.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
The inventors believe that persons of skill in the art do not understand the
problem that leads to cost-
effective manufacturing of injection-molding systems, and that by
understanding the problem, it is
believed that a better understanding of the non-limiting embodiments is
realized.
FIG. lA depicts the schematic representation of the injector unit 100
according to the first non-
limiting embodiment, in which the injector unit 100 includes: (i) a
prefabricated screw-rotation
actuator 102A, and (ii) a prefabricated screw-translation actuator 106A. The
prefabricated screw-
rotation actuator 102A is selected from a group 104 that has prefabricated
screw-rotation actuators
102A; 102B; 102C. The prefabricated screw-translation actuator 106A is
selected from a collection
108 having prefabricated screw-translation actuators 106A; 106B; 106C. The
prefabricated screw-
rotation actuator 102A is used to rotate a melt-processing screw 114 (depicted
in FIG. 2) that is
disposed in a barrel assembly 112 of an injector unit 100. The prefabricated
screw-translation actuator
106A. is used to translate the melt-processing screw 114.
Fig. 1B depicts a condition or relationaship between the prefabricated screw-
rotation actuators 102A;
102B; 102C and the prefabricated screw-rotation actuators 102A; 102B; 102C, in
which each of the
prefabricated screw-translation actuator 106A; 106B; 106C is cooperative with
each of the
prefabricated screw-rotation actuators 102A; 102B; 102C. It will be
appreciated that it is not required
to arrange the prefabricated actuators according to the arrangement depicted
in FIG. 1B. A more
likely arrangement is that the prefabricated screw-translation actuators 106A;
106B; 106C are
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cooperative with at least one of the prefabricated screw-rotation actuators
102A; 102B; 102C. The
term "cooperative" means that the prefabricated screw-rotation actuators 102A;
102B; 102C and the
prefabricated screw-rotation actuators 102A; 102B; 102C are interface
compatible with each other
and cooperate to be operable with the melt-processing screw 114.
The prefabricated screw-rotation actuators 102A; 102B; 102C and the
prefabricated screw-rotation
actuators 102A; 102B; 102C are actuators that are: (i) manufactured in
standardized assemblies, and
(ii) ready for assembly into the injector unit 100 that is to be used in an
injection-molding system 99
(depicted in FIG. 2). A technical effect, amongst other technical effects, is
improved cost-
effectiveness associated with manufacturing injection units associated with
injection-molding
systems. For a given molding problem or application that is required by: (i) a
producer to mold
articles, and/or (ii) a manufacturer or supplier of injection units and/or of
injection-molding systems
having the injector units, may be able to choose from (mixing and matching) a
predetermined
selection of available prefabricated actuators, so that the manufacturer of
the injection unit may
operatively assemble the selected prefabricated actuators with the melt-
processing screw 114, and in
this manner the assembled injection unit may satisfy a particular application
that is desired for
manufacturing molded articles. In this way, the injection unit is configurable
and usable for a specific
molding requirement (that is, to mold specific articles). In sharp contrast to
the known art, if a
manufacturer of a molding system could not satisfy the requirements associated
with molding articles
according to the needs of a molder, then a custom adaptation of an existing
molding system would
have to be contemplated, at a much higher cost that would be passed onto the
molder or manufacturer
of molded articles.
FIG. 2 depicts the schematic representation of the injector unit 100 according
to the second non-
limiting embodiment, in which the prefabricated screw-translation actuator
106A is couplable with
the melt-processing screw 114 that is accommodated by the barrel assembly 112
of the injector unit
100, so that responsive to actuation of the prefabricated screw-translation
actuator 106A, the melt-
processing screw 114 translates linearly. The prefabricated screw-rotation
actuator 102A is couplable
with the prefabricated screw-translation actuator 106A, so that responsive to
actuation of the
prefabricated screw-rotation actuator 102A, the melt-processing screw 114
rotates. The prefabricated
screw-rotation actuator 102A and the prefabricated screw-translation actuator
106A cooperate to
acutate the melt-processing screw 114, as may be required. The injection-
molding system 99
includes: (i) the injector unit 100, and (ii) a clamp assembly 98.
FIG. 3 depicts the schematic representation of the injector unit 100 according
to the third non-limiting
embodiment, in which the prefabricated screw-rotation actuator 102A is
couplable with the melt-
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processing screw 114, so that responsive to actuation of the prefabricated
screw-rotation actuator
102A, the melt-processing screw 114 rotates. The prefabricated screw-
translation actuator 106A is
couplable with the prefabricated screw-rotation actuator 102A, so that
responsive to actuation of the
prefabricated screw-translation actuator 106A, the melt-processing screw 114
translates linearly.
FIG. 4 depicts the schematic representation of the injector unit 100 according
to the fourth non-
limiting embodiment, in which the injector unit 100 further includes a
prefabricated transmission unit
120A that is selected from an assemblage 122 having prefabricated transmission
units 120A; 120B;
120C. Each of the prefabricated transmission units 120A; 120B; 120C is
couplable with the melt-
processing screw 114. The prefabricated screw-rotation actuator 102A is
couplable with the
prefabricated transmission unit 120A, so that responsive to actuation of the
prefabricated screw-
rotation actuator 102A, the melt-processing screw 114 rotates. The
prefabricated screw-translation
actuator 106A is couplable with prefabricated transmission unit 120A, so that
responsive to actuation
of the prefabricated screw-translation actuator 106A, the melt-processing
screw 114 translates
linearly.
FIG. 5 depicts another schematic representation of the injector unit 100
according to the fourth non-
limiting embodiment, in which the prefabricated transmission units 120A; 120B;
120C are: (i)
cooperative with at least one of the prefabricated screw-rotation actuators
102A; 102B; 102C, and
(ii) cooperative with at least one of the prefabricated screw-translation
actuator 106A; 106B; 106C.
FIG. 6 depicts the schematic representation of the injector unit 100 according
to the fifth non-limiting
embodiment, in which the barrel assembly 112A is selected from a set 115 of
barrel assemblies
112A; 112B; 112C. The barrel assembly 112A is cooperative with: (i) at least
one of the
prefabricated screw-translation actuators 106A; 106B; 106C, and/or (ii) is
cooperative with at least
one of the prefabricated screw-rotation actuators 102A; 102B; 102C.
FIG. 7 depicts another schematic representation of the injector unit 100
according to the fifth non-
limiting embodiment, in which the barrel assembly 112A is cooperative with at
least one of the
prefabricated transmission units 120A; 120B; 120C.
FIG. 8 depicts the schematic representation of the injector unit 100 according
to the sixth non-
limiting embodiment, in which the prefabricated screw-translation actuator
106A, includes: (i) a rear
assembly 130A, and (ii) a front assembly 140A. The rear assembly 130A is
selected from a collective
132 of rear assemblies 130A; 130B; 130C. The front assembly 140A is selected
from an assortment
142 of front assemblies 140A; 140B; 140C.
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FIG. 9 depicts the schematic representation of the injector unit 100 according
to the seventh non-
limiting embodiment, in which the prefabricated screw-rotation actuator 102A
includes: (i) a first
module 150A, and (ii) a second module 160A. The first module 150A is selected
from a grouping
152 of first modules 150A; 150B; 150C. The second module 160A is selected from
an allocation 162
of second modules 160A; 160B; 160C.
FIGS. 10 to 13 depict perspective views of the injector unit 100 according to
the second non-limiting
embodiment depicted in FIG. 2.
FIG. 10 depicts a general-purposed injection-molding system.
FIG. 11 depicts an injection-molding system that is used for manufacturing
thin-walled packaging,
such as food-bearing containers, etc.
FIG. 12 depicts an injection-molding system that is used for manufacturing
metallic articles, such as
laptop cases, cell-phone housings, automobile parts, etc.
FIG. 13 depicts an injection-molding system that is used for manufacturing PET
Polyethylene
Terephthalate performs.
FIGS. 14 and 15 depict cross sectional views of the injector unit 100
according to the eighth non-
limiting embodiment. The prefabricated screw-translation actuator 106A
includes: (i) a front
assembly 140A, and (ii) a rear assembly 130A.
The front assembly 140A includes a front housing 220 that is configured to
receive and to
accommodate the barrel assembly 112, and the barrel assembly 112 accommodates
the melt-
processing screw 114. A collar 222 is fitted around the end of the barrel
assembly 112 so that the
barrel assembly 112 is held stationary relative to the front housing 220. The
front housing 220 is
supported by a linear bearing 224 (also called a first linear bearing) that is
mounted to a plate 226,
and the linear bearings 224 permit the front housing 220 to slide relative to
the plate 226. A carriage
cylinder (not depicted, but known) is coupled with the front housing 220 so
that the carriage cylinder
may be used to linearly translate the front housing forward so that the
machine nozzle (not depicted,
but known) that is attached to the front end of the barrel assembly 112 may
contact a sprue or conduit
that leads to a mold or a hot runner, etc, as may be required.
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The rear assembly 130A includes a rear housing 330 that is connected (using
bolts) with the front
housing 220. In this way, the front housing 220 and the rear housing 230 may
be interfaced with each
other. The rear housing 330 defines a cylinder therein. The rear assembly 130A
also includes a piston
332 that is linearly translatable along the cylinder defined by the rear
housing 330. The piston 332 is
connected with an end portion of the melt-processing screw 114. When the
piston 332 is made to
translate linearly, the melt-processing screw 114 will also translate
linearly. The rear assembly 130A
also includes a seal assembly 334 that is used to seal the cylinder defined by
the rear housing 330
from the front housing 220. The cylinder includes: (i) a bore chamber 336 and
(ii) a rod chamber 338.
The bore chamber 336 and the rod chamber 338 are both pressurizable by way of
a hydraulic fluid
that is pumped into the cylinder or removed from the chambers 336, 338.
Fig. 14 depicts the piston 332 in a retracted position; that is, the melt-
processing screw 114 is
retraced. To retract the melt-processing screw 114, the bore chamber 336 is
pressurized while the rod
chamber 338 is unpressurized, so that the piston 332 may be moved toward the
right-hand side of
FIG. 14.
Fig. 15 depicts the piston 332 in an injection position, in which the bore
chamber 336 is
unpressurized while the rod chamber 338 is pressurized so that the piston 332
may be moved to the
left-hand side of FIG. 15. The rear housing 330 is mounted to a linear bearing
339 (also called a
second linear bearing), and the linear bearing 339 is mounted with the plate
226, so that the rear
housing 330 may be translated linearly with the front housing 220. The piston
332 includes a piston
shaft 333 that extends along a longitudinal axis of the piston 332 away from
the front housing 220.
The piston shaft 333 includes a spline insert 335 that is attached with an end
of the piston shaft 333.
The spline insert defines channels that extend from one end of the spline
insert 335 to the other end of
the spline insert 335.
The prefabricated screw-rotation actuator 102 includes: (i) a housing 202,
(ii) a stator 204 that is
mounted to the housing 202, (iii) a rotor 206 that is rotatable relative to
the stator 204, (iv) an end
cover 208, (v) a lift handle 210 connected with the housing 202, and (vi) a
power box 212 that is
mounted to the housing 202, so that power may be delivered to energize the
stator 204 and the rotor
206. The housing 202 is connected with the rear housing 330 by way of bolts
213. In this way, the
front housing 220 is interface compatible with the rear housing 330.
A spline sleeve 214 is fixedly mounted with (one end oo the rotor 206, and
extends inside the front
housing 220. As depicted, the spline sleeve 214 is connected with the rotor
206, so that when the
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rotor 206 is made to rotate, the spline sleeve 214 may rotate as well. The
spline sleeve 214 includes
splines 216 that extend along the longitudinal axis of the housing 202. The
spline sleeve 214 is filled
with oil.
The spline insert 335, which is attached with the end of the piston shaft 333,
is slidably matable with
the spline sleeve 214, so that the spline insert 335 may be linearly
translated along the spline sleeve
214 when the piston 332 is made to be translated linearly. When the spline
insert 335 is made to
translate linearly, the oil in the spline sleeve 214 may move freely through
the channels defined by the
spline insert 335.
In operation, when the stator 204 is energized, the rotor 206 is made to
rotate, and the spline sleeve
214 is also made to rotate. This arrangmenet will cause the spline insert 335
to rotate, and in turn the
piston 332 will rotate. In this arrangement, the melt-processing screw 114
will then rotate. For the
case when the stator 204 is de-energized, the piston 332 may be translated
linearly, and the spline
insert 335 will slide relative to the spline sleeve 214, while oil is made to
pass through the
passageways defined by the spline insert 335.
A sensor 400 is mounted to the end cover 208. The sensor 400 includes a sensor
shaft 402 that
extends from the sensor 400 into a bore that is defined in the end of the
piston shaft 333. The sensor
400 is used to detect the position of the piston 332. An example of the sensor
400 is a position sensor,
which uses magnets. The sensor 400 is manufactured by MTS Sensors
(http://www.mtssensors.com
and is sold under the trade name of Temposonic (trademark).
The description of the non-limiting embodiments provides non-limiting examples
of the present
invention; these non-limiting examples do not limit the scope of the claims of
the present invention.
The non-limiting embodiments described are within the scope of the claims of
the present invention.
The non-limiting embodiments described above may be: (i) adapted, modified
and/or enhanced, as
may be expected by persons skilled in the art, for specific conditions and/or
functions, without
departing from the scope of the claims herein, and/or (ii) further extended to
a variety of other
applications without departing from the scope of the claims herein. It is to
be understood that the non-
limiting embodiments illustrate the aspects of the present invention.
Reference herein to details and
description of the non-limiting embodiments is not intended to limit the scope
of the claims of the
present invention. Other non-limiting embodiments, which may not have been
described above, may
be within the scope of the appended claims. It is understood that: (i) the
scope of the present
invention is limited by the claims, (ii) the claims themselves recite those
features regarded as
essential to the present invention, and (iii) preferable embodiments of the
present invention are the
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CA 02607390 2007-10-23
H-7157-0-CA
subject of dependent claims. Therefore, what is to be protected by way of
letters patent are limited
only by the scope of the following claims:
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