CN111452313B - Plasticizing unit and injection molding machine - Google Patents

Plasticizing unit and injection molding machine Download PDF

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Publication number
CN111452313B
CN111452313B CN202010051228.9A CN202010051228A CN111452313B CN 111452313 B CN111452313 B CN 111452313B CN 202010051228 A CN202010051228 A CN 202010051228A CN 111452313 B CN111452313 B CN 111452313B
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China
Prior art keywords
plasticizing
screw
axis
drive
unit according
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Application number
CN202010051228.9A
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Chinese (zh)
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CN111452313A (en
Inventor
C·巴尔卡
F·佩恩科普夫
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Engel Austria GmbH
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Engel Austria GmbH
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Publication of CN111452313A publication Critical patent/CN111452313A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17Component parts, details or accessories; Auxiliary operations
    • B29C45/46Means for plasticising or homogenising the moulding material or forcing it into the mould
    • B29C45/47Means for plasticising or homogenising the moulding material or forcing it into the mould using screws
    • B29C45/50Axially movable screw
    • B29C45/5008Drive means therefor
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17Component parts, details or accessories; Auxiliary operations
    • B29C45/46Means for plasticising or homogenising the moulding material or forcing it into the mould
    • B29C45/47Means for plasticising or homogenising the moulding material or forcing it into the mould using screws
    • B29C45/50Axially movable screw
    • B29C45/5008Drive means therefor
    • B29C2045/504Drive means therefor electric motors for rotary and axial movement of the screw being coaxial with the screw
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17Component parts, details or accessories; Auxiliary operations
    • B29C45/46Means for plasticising or homogenising the moulding material or forcing it into the mould
    • B29C45/47Means for plasticising or homogenising the moulding material or forcing it into the mould using screws
    • B29C45/50Axially movable screw
    • B29C45/5008Drive means therefor
    • B29C2045/5056Drive means therefor screws axially driven by a rotatable screw shaft cooperating with a fixed nut

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Injection Moulding Of Plastics Or The Like (AREA)

Abstract

The invention relates to a plasticizing unit (1) for an injection molding machine, comprising at least one plasticizing cylinder (2), in which a single plasticizing screw (3) is mounted so as to be movable along an axis (A) of the plasticizing cylinder (2) and so as to be rotatable about the axis (A) of the plasticizing cylinder (2) by means of a first drive, wherein the first drive has a shaft (5) that can be driven by a motor (4) in order to rotate the plasticizing screw (3) about the axis (A) of the plasticizing cylinder (2), and a transmission is provided, by means of which the rotational movement (5) of the shaft can be converted into a rotational movement (3) of the plasticizing screw, wherein the shaft (5) of the first drive forms an acute angle (alpha) with the axis (A) of the plasticizing cylinder (2). The invention also relates to an injection molding machine.

Description

Plasticizing unit and injection molding machine
Technical Field
The invention relates to a plasticizing unit and to an injection molding machine having such a plasticizing unit.
Background
In the same type of plasticizing unit, the available space for the first drive is extremely limited. In order to transmit the rotational movement of the shaft of the motor of the first drive to the plasticizing screw, a transmission is used in the same type of plasticizing unit, which increases the mass of rotation and translation to be driven. Different types of plasticizing units are also known, in which the shaft of the motor of the first drive is arranged coaxially to the plasticizing screw in a direct drive, which reduces the mass of rotation and translation to be driven compared to the same type of plasticizing unit. However, these different types of plasticizing units have the disadvantage that, without a transmission mechanism, it is not possible to transmit the rotational movement of the shaft of the motor of the first drive relative to the rotational movement of the plasticizing screw.
Disclosure of Invention
The object of the invention is to provide a plasticizing unit of the same type and an injection molding machine having a plasticizing unit of this type, for which the mass of the rotation and translation to be driven can be reduced compared to a plasticizing unit of the same type according to the prior art, despite the provision of a transmission between the shaft of the motor of the first drive and the plasticizing screw.
The object is achieved by a plasticizing unit and an injection molding machine having such a plasticizing unit.
A plasticizing unit for an injection molding machine has at least one plasticizing cylinder, in which a single plasticizing screw is mounted so as to be movable along the axis of the plasticizing cylinder and so as to be rotatable about the axis of the plasticizing cylinder by means of a first drive, wherein the first drive has a shaft which can be driven by a motor in order to rotate the plasticizing screw about the axis of the plasticizing cylinder, and a transmission is provided, by means of which the rotational movement of the shaft can be converted into a rotational movement of the plasticizing screw, characterized in that the shaft of the first drive forms an acute angle with the axis of the plasticizing cylinder.
The injection molding machine has a plasticizing unit according to the invention.
Provision is made for the shaft of the first drive to form an acute angle with the axis of the plasticizing cylinder. It is thereby possible to achieve a high transmission ratio with a single-stage and therefore compact transmission. The advantage of the compactness of the transmission is the reduction of the mass of rotation and translation to be driven.
In one embodiment of the invention, it is provided that the central axis of the shaft and the axis of the plasticizing cylinder are arranged in the same plane, wherein it is preferably provided that this plane extends vertically.
In one embodiment of the invention, it is provided that an imaginary extension of the central axis of the shaft and the axis of the plasticizing cylinder intersect at an intersection point. In this case, it can be provided that the point of intersection is located between the tip and the shank of the plasticizing screw. This makes it possible to achieve an acute angle with a smaller gear, which reduces the inertia.
The acute angle is in the range between 10 ° and 45 °.
In one embodiment of the invention, a second drive is provided for moving the plasticizing screw along the axis of the plasticizing cylinder. In this case, it can be provided that the second drive device has a motor and a device for converting the rotary motion of the motor into a linear motion.
In this case, it can be provided that the device for converting the rotary motion of the motor into a linear motion has a spindle drive, which comprises a spindle and a spindle nut, wherein either the spindle or the spindle nut is rotatable by the motor of the second drive, and the spindle nut or the spindle is movably connected to the plasticizing screw. Preferably, the spindle drive is embodied as a ball screw drive.
In this case, it can be provided that the spindle is arranged parallel to, preferably coaxially with, the axis of the plasticizing cylinder and thus forms an acute angle with the axis of the first drive.
In one exemplary embodiment of the invention, it is provided that the gear mechanism is designed as a bevel gear mechanism, a helical gear mechanism (zylinderschugetriebe), a conical spur gear mechanism (kegeliges Stirnradgetriebe) or as a planetary gear mechanism, which has an inclined toothing in an internally toothed sun gear.
In one embodiment of the invention, it is provided that the transmission has an angular joint. The angle joint can be designed, for example, as a universal joint, a constant velocity joint or a cross joint.
In one embodiment of the invention, it is provided that the plasticizing unit has two plasticizing cylinders, in which a single plasticizing screw is mounted so as to be movable along the axis of the respective plasticizing cylinder and so as to be rotatable about the axis of the respective plasticizing cylinder by means of a first drive, wherein the first drive has a shaft which can be driven by a motor in order to rotate the plasticizing screw about the axis of the respective plasticizing cylinder, wherein the shaft forms an acute angle in accordance with the axis of the respective plasticizing cylinder, and a transmission is provided by means of which the rotational movement of the shaft can be converted into a rotational movement of the plasticizing screw.
In this case, it is preferably provided that the two plasticizing cylinders are arranged in a W-shaped arrangement.
Drawings
Embodiments of the invention are discussed with the aid of the figures. Wherein:
figure 1 shows a schematic cross-sectional view of a first embodiment of the invention,
figure 2 shows a schematic cross-sectional view of a second embodiment of the invention,
figures 3a and 3b show schematic cross-sectional views of third and fourth embodiments of the invention,
figure 4 shows a schematic cross-sectional view of a fifth embodiment of the invention,
fig. 5 shows a schematic cross-sectional view of a sixth embodiment of the invention.
Detailed Description
Fig. 1 shows a schematic cross-sectional view of a plasticizing unit 1 having a plasticizing cylinder 2 (not shown in the drawing for the sake of clarity) in which a single plasticizing screw 3 is mounted so as to be displaceable along an axis a of the plasticizing cylinder 2 and so as to be rotatable about the axis a of the plasticizing cylinder 2 by means of a first drive. For rotating the plasticizing screw 3 about the axis a of the plasticizing cylinder 2, a first drive is provided, which has a shaft 5 that can be driven by a motor 4, the rotational movement of which can be converted into a rotational movement of the plasticizing screw 3 by means of a transmission. The gear mechanism is in this embodiment in the form of a conical spur gear mechanism.
According to the invention, the shaft 5 of the first drive forms an acute angle α (here approximately 30 °) with the axis a of the plasticizing cylinder 2. The central axis of the shaft 5 and the axis a of the plasticizing cylinder 2 are arranged in the same vertically extending plane (corresponding to the drawing sheet and the sectional plane in this figure). It can be seen that an imaginary extension W of the central axis of the shaft 5 and the axis a of the plasticizing cylinder 2 intersect at an intersection point P, which in this embodiment is between the tip 9 and the shank 10 of the plasticizing screw 3.
In order to move the plasticizing screw 3 along the axis a of the plasticizing cylinder 2, a second drive is provided, which in this embodiment has a motor 6 and a device for converting the rotary motion of the motor 6 into a linear motion. The device for converting the rotary motion of the motor 6 into a linear motion has a spindle drive with a spindle 7 and a spindle nut 8, wherein in this exemplary embodiment the spindle 7 is rotatable by the motor 6 of the second drive and the spindle nut 8 is connected to the plasticizing screw 3 in a rotationally fixed but displaceable manner. The rotational movement of the motor 6 of the second drive is transmitted from the motor 6 to the spindle 7 via a belt. In this embodiment, the screw 7 is arranged parallel and/or coaxially to the axis a of the plasticizing cylinder 2 and thus forms an acute angle α with the shaft 5 of the first drive.
In the embodiment of fig. 2, the means for converting the rotary motion of the motor 6 into a linear motion have a ball screw transmission.
Fig. 3 shows two further exemplary embodiments in which the device for converting the rotary motion of the motor 6 into a linear motion has one (fig. 3a) or two (fig. 3b) ball screw drives, wherein in each case one spindle nut 8 is arranged rotatably and in each case one spindle 7 is connected in a rotationally fixed but displaceable manner to the plasticizing screw 3.
Fig. 4 shows an embodiment according to fig. 2, however, the plasticizing unit 1 has two plasticizing cylinders 2, in each of which a single plasticizing screw 3 is mounted so as to be movable along the axis a of the respective plasticizing cylinder 2 and so as to be rotatable about the axis a of the respective plasticizing cylinder 2 by means of a first drive in the two plasticizing cylinders 2, wherein the first drive has a shaft 5 which is drivable by means of a motor 4 in order to rotate the plasticizing screw 3 about the axis a of the respective plasticizing cylinder 2, wherein the shaft 5 forms an acute angle α in accordance with the axis a of the respective plasticizing cylinder 2, and a transmission is provided in each case, by means of which the rotational movement of the shaft 5 can be converted into a rotational movement of the plasticizing screw 3. The two plasticizing cylinders 2 are arranged in a W-shaped arrangement.
In the embodiment of fig. 5, the transmission has an angular joint 11. The angle joint can be, for example, a universal joint, a constant velocity joint or a cross joint.
List of reference numerals:
1 plasticizing unit
2 plasticizing cylinder
3 plasticizing screw
4 motor of first driving device
5 shaft of the first drive
6 Motor of second drive device
7 screw rod of second driving device
8 feed screw nut of second driving device
9 tip of plasticizing screw
10 plasticizing shank of screw
11-angle movable joint
Axis of A plasticizing cylinder
W imaginary extension of the central axis of the shaft of the first drive
P W and A intersection
Angle alpha between the axis of the first drive and the axis of the plasticizing cylinder

Claims (16)

1. Plasticizing unit (1) for an injection molding machine, having at least one plasticizing cylinder (2) in which a single plasticizing screw (3) is mounted so as to be movable along the axis (A) of the plasticizing cylinder (2) and so as to be rotatable about the axis (A) of the plasticizing cylinder (2) by means of a first drive, wherein the first drive has a shaft (5) which can be driven by a motor (4) in order to rotate the plasticizing screw (3) about the axis (A) of the plasticizing cylinder (2), and a transmission is provided by means of which the rotational movement of the shaft (5) can be converted into a rotational movement of the plasticizing screw (3), characterized in that the shaft (5) of the first drive forms an acute angle (α) with the axis (A) of the plasticizing cylinder (2).
2. Plasticizing unit according to claim 1, wherein the central axis of the shaft (5) and the axis (a) of the plasticizing cylinder (2) are arranged in the same plane.
3. A plasticizing unit according to claim 1 or 2, wherein an imaginary extension (W) of the central axis of the shaft (5) and the axis (a) of the plasticizing cylinder (2) intersect at an intersection point (P).
4. Plasticizing unit according to claim 3, wherein the point of intersection (P) is between the tip (9) and the shank (10) of the plasticizing screw (3).
5. Plasticizing unit according to claim 1 or 2, wherein the acute angle (α) is in the range between 10 ° and 45 °.
6. Plasticizing unit according to claim 1 or 2, wherein a second drive is provided for moving the plasticizing screw (3) along the axis (a) of the plasticizing cylinder (2).
7. A plasticizing unit according to claim 6, wherein the second drive means has a motor (6) and means for converting the rotational movement of the motor (6) of the second drive means into a linear movement.
8. A plasticizing unit according to claim 7, wherein the means for converting the rotational movement of the motor (6) of the second drive into a linear movement has a screw drive comprising a screw (7) and a screw nut (8), wherein either the screw (7) or the screw nut (8) is rotatable by the motor (6) of the second drive and the screw nut (8) or the screw (7) is movably connected to the plasticizing screw (3).
9. Plasticizing unit according to claim 8, wherein the screw (7) is arranged parallel to the axis (A) of the plasticizing cylinder (2) and thus forms an acute angle (α) with the shaft (5) of the first drive means.
10. Plasticizing unit according to claim 1 or 2, wherein the gear mechanism is designed as a bevel gear mechanism, a helical gear mechanism, a conical spur gear mechanism or as a planetary gear mechanism with an inclined toothing in the internally toothed sun gear.
11. Plasticizing unit according to claim 1 or 2, wherein the transmission mechanism has an angular joint (11).
12. A plasticizing unit according to claim 1 or 2, wherein the plasticizing unit (1) has two plasticizing cylinders (2), in which one single plasticizing screw (3) is movably supported along the axis (A) of the respective plasticizing cylinder (2) and rotatably about the axis (A) of the respective plasticizing cylinder (2) by means of a first drive, wherein the first drive for rotating the plasticizing screw (3) about the axis (A) of the respective plasticizing cylinder (2) has a shaft (5) which can be driven by a motor (4), wherein the shafts (5) form an acute angle (alpha) in correspondence with the axis (A) of the respective plasticizing cylinder (2), and a transmission mechanism is provided in each case, by means of which the rotary motion of the shaft (5) can be converted into a rotary motion of the plasticizing screw (3).
13. Plasticizing unit according to claim 12, wherein the two plasticizing cylinders (2) are provided in a W-shaped arrangement.
14. The plasticizing unit of claim 2, wherein the plane extends vertically.
15. Plasticizing unit according to claim 9, wherein the screw (7) is arranged coaxially with the axis (a) of the plasticizing cylinder (2).
16. Injection molding machine having a plasticizing unit according to one of claims 1 to 15.
CN202010051228.9A 2019-01-18 2020-01-17 Plasticizing unit and injection molding machine Active CN111452313B (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ATA50039/2019 2019-01-18
ATA50039/2019A AT522057B1 (en) 2019-01-18 2019-01-18 Plasticizing unit for an injection molding machine

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CN111452313A CN111452313A (en) 2020-07-28
CN111452313B true CN111452313B (en) 2021-12-10

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AT (1) AT522057B1 (en)
DE (1) DE102020100664B4 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT523837B1 (en) 2020-10-15 2021-12-15 Engel Austria Gmbh Injection unit for a molding machine
CN112810053A (en) * 2021-02-04 2021-05-18 谢科珂 Injection molding machine injection platform driving structure

Citations (9)

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Publication number Priority date Publication date Assignee Title
GB1166061A (en) * 1966-08-19 1969-10-01 Foster Yates & Thom Ltd Improvements in or relating to Preplasticising Injection Apparatus
JPH02305618A (en) * 1989-04-25 1990-12-19 Toyo Mach & Metal Co Ltd Regulating device of angle of slant plate of variable delivery pump for injection molding machine
JPH032008A (en) * 1989-05-31 1991-01-08 Ee I Tec:Kk Parts feeder apparatus
US6015284A (en) * 1997-04-09 2000-01-18 Engel Maschinenbau Gesellschaft M.B.H. Injection unit for injection molding machines
US6425753B1 (en) * 1998-12-07 2002-07-30 Engel Maschinenbau Gesellschaft M.B.H. Injection unit for an injection molding machine
JP2002317863A (en) * 2001-04-19 2002-10-31 Mitsubishi Heavy Ind Ltd Ball screw device and injection molding machine equipped therewith
CN1427762A (en) * 2000-05-08 2003-07-02 普罗控制公开股份有限公司 Method and device for injection moulding or pressing of plastic components
JP2008143022A (en) * 2006-12-11 2008-06-26 Meiki Co Ltd Injection device and operating method thereof
CN103934991A (en) * 2014-05-15 2014-07-23 阮祺 Glue injection device for injection molding machine

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Publication number Priority date Publication date Assignee Title
US3380116A (en) * 1966-10-13 1968-04-30 Baker Perkins Inc Mixing machine drive
JPS59230733A (en) * 1983-06-13 1984-12-25 Japan Steel Works Ltd:The Screw driver for injection molding machine
AT5681U1 (en) 2001-10-15 2002-10-25 Engel Gmbh Maschbau DEVICE FOR PLASTICIZING AND INJECTING PLASTIC
JP5631814B2 (en) * 2011-06-17 2014-11-26 住友重機械工業株式会社 INJECTION DEVICE AND CORE ADJUSTING METHOD
CN107685436B (en) * 2017-11-03 2019-09-10 许梦艳 A kind of ultra-high molecular weight polyethylene plasticized screw extruder

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1166061A (en) * 1966-08-19 1969-10-01 Foster Yates & Thom Ltd Improvements in or relating to Preplasticising Injection Apparatus
JPH02305618A (en) * 1989-04-25 1990-12-19 Toyo Mach & Metal Co Ltd Regulating device of angle of slant plate of variable delivery pump for injection molding machine
JPH032008A (en) * 1989-05-31 1991-01-08 Ee I Tec:Kk Parts feeder apparatus
US6015284A (en) * 1997-04-09 2000-01-18 Engel Maschinenbau Gesellschaft M.B.H. Injection unit for injection molding machines
US6425753B1 (en) * 1998-12-07 2002-07-30 Engel Maschinenbau Gesellschaft M.B.H. Injection unit for an injection molding machine
CN1427762A (en) * 2000-05-08 2003-07-02 普罗控制公开股份有限公司 Method and device for injection moulding or pressing of plastic components
JP2002317863A (en) * 2001-04-19 2002-10-31 Mitsubishi Heavy Ind Ltd Ball screw device and injection molding machine equipped therewith
JP2008143022A (en) * 2006-12-11 2008-06-26 Meiki Co Ltd Injection device and operating method thereof
CN103934991A (en) * 2014-05-15 2014-07-23 阮祺 Glue injection device for injection molding machine

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Publication number Publication date
CN111452313A (en) 2020-07-28
DE102020100664B4 (en) 2024-02-22
AT522057B1 (en) 2020-09-15
AT522057A1 (en) 2020-08-15
DE102020100664A1 (en) 2020-07-23

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