US4968239A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct-pressure type mold clamping mechanism
Assignee: Fanuc Corp
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Filing: 1987-06-25
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Granted: 1990-11-06
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Expires: 2007-06-25
Abstract
Abstract A motor-operated, direct-pressure type mold clamping apparatus is capable of high-speed mold closing and opening operations and of producing a required mold clamping force, without the use of a large-sized motor. In the mold opening and closing operations, a ball screw, in engagement with a ball nut which is movable in one with a moving platen, is rotated at high speed by a motor through gears and a clutch, so that a die is opened and closed at high speed. In a mold clamping operation, the ball screw is driven with a large rotatory force transmitted through a clutch and gears which, having a high reduction ratio, serve to increase the rotatory force of the motor. Thus, dies are clamped with a large clamping force.
Inventors
- 👤 Yoshiharu Inaba
- 👤 Fumio Mitoguchi
- 👤 Hiromasa Yamashita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:39
CPC Classifications
B; B29; B29C; B29C45/00; B29C45/17; B29C45/64; B29C45/66; Y; Y10; Y10S; Y10S425/00; Y10S425/223; Y10T; Y10T74/00; Y10T74/18; Y10T74/18568; Y10T74/18576; Y10T74/18696; Y10T74/19; Y10T74/19014
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
243 words
A direct-pressure mold clamping apparatus for an injection-molding machine having a moving platen, comprising: conversion means including a rotating member and a rectilinear motion member movable in unison with the moving platen, said conversion means for converting rotary motion of said rotating member into rectilinear motion of said rectilinear motion member; a feed table movably supporting said moving platen; a motor having a drive shaft for driving the rotating member of said conversion means; a transmission coupled to the motor; a first ball screw/nut mechanism for course-adjustment having a course-adjustment nut coupled to said feed table and a course-adjustment ball screw driven by said motor through said transmission for moving the moving platen under a relatively high speed, low torque condition; a second ball screw/nut mechanism for fine adjustment having a fine-adjustment nut fixedly coupled to said moving platen and a fine-adjustment ball screw spline-coupled to a speed reducer and being driven by said motor for moving the moving platen under a relatively low speed, high torque condition; said transmission transmitting the rotation of said motor drive shaft to said course-adjustment ball screw; said speed reducer for reducing the rotational speed of said fine-adjustment ball screw while increasing the rotary force of said motor, and transmitting the rotary force of said motor to said fine-adjustment ball screw; and switching means for alternatively connecting said motor to said fine-adjustment ball screw and said course-adjustment ball screw through said transmission and said speed reducer, respectively.
Claim 2
Dependent Claim
243 words
A direct-pressure mold clamping apparatus for an injection-molding machine having a moving platen, comprising: conversion means including a rotating member and a rectilinear motion member movable in unison with the moving platen, said conversion means for converting rotary motion of said rotating member into rectilinear motion of said rectilinear motion member; a feed table movably supporting said moving platen; a motor having a drive shaft for driving the rotating member of said conversion means; a transmission coupled to the motor; a first ball screw/nut mechanism for course-adjustment having a course-adjustment nut coupled to said feed table and a course-adjustment ball screw driven by said motor through said transmission for moving the moving platen under a relatively high speed, low torque condition; a second ball screw/nut mechanism for fine adjustment having a fine-adjustment nut fixedly coupled to said moving platen and a fine-adjustment ball screw spline-coupled to a speed reducer and being driven by said motor for moving the moving platen under a relatively low speed, high torque condition; said transmission transmitting the rotation of said motor drive shaft to said course-adjustment ball screw; said speed reducer for reducing the rotational speed of said fine-adjustment ball screw while increasing the rotary force of said motor, and transmitting the rotary force of said motor to said fine-adjustment ball screw; and switching means for alternatively connecting said motor to said fine-adjustment ball screw and said course-adjustment ball screw through said transmission and said speed reducer, respectively.
Claim 3
Dependent Claim
18 words
A direct-pressure mold clamping apparatus according to claim 1, further comprising braking means for locking said rotating member.
Claim 4
Dependent Claim
43 words
A direct-pressure mold clamping apparatus according to claim 1 further comprising a sensor for detecting the position of the moving platen, and a control device for controlling said motor based on the position detected by the sensor, wherein said motor is a servomotor.
Claim 5
Dependent Claim
87 words
A direct-pressure mold clamping apparatus according to claim 1, wherein said switching means includes a first clutch for connecting and disconnecting said course-adjustment ball screw from the motor shaft, braking means for locking the rotation of said course-adjustment ball screw, a second clutch for connecting and disconnecting said fine-adjustment ball screw from the motor shaft, and braking means for locking the rotation of said fine-adjustment ball screw, said fine-adjustment nut being axially slidable with respect to said coarse-adjustment nut and movable in unison with said moving platen.
Claim 6
Dependent Claim
190 words
A mold clamping apparatus having a movable die fixed to a movable platen and a stationary platen, the apparatus comprising: a motor having a rotary power output shaft; a feed table movably supporting the movable platen; a first ball nut supported on the feed table; a first ball screw threadedly engaging the first ball nut and having a rotatably supported integrally formed shaft driven by the motor to move the movable platen and the feed table in unison under a relatively high speed, low torque condition; a second ball nut fixedly connected to the movable platen; a second ball screw threadedly engaging the ball nut and having a rotatably supported integrally formed shaft driven by the motor for moving the movable platen relative to the feed table under a relatively low speed, high torque condition; a transmission for transmitting power from the motor shaft to the first ball screw shaft; a speed reducer for transmitting power from the motor shaft to the second ball screw shaft at a reduced rotational speed and increased torque; and switching means for alternatively connecting the transmission and the speed reducer to the motor shaft.
Claim 7
Dependent Claim
190 words
A mold clamping apparatus having a movable die fixed to a movable platen and a stationary platen, the apparatus comprising: a motor having a rotary power output shaft; a feed table movably supporting the movable platen; a first ball nut supported on the feed table; a first ball screw threadedly engaging the first ball nut and having a rotatably supported integrally formed shaft driven by the motor to move the movable platen and the feed table in unison under a relatively high speed, low torque condition; a second ball nut fixedly connected to the movable platen; a second ball screw threadedly engaging the ball nut and having a rotatably supported integrally formed shaft driven by the motor for moving the movable platen relative to the feed table under a relatively low speed, high torque condition; a transmission for transmitting power from the motor shaft to the first ball screw shaft; a speed reducer for transmitting power from the motor shaft to the second ball screw shaft at a reduced rotational speed and increased torque; and switching means for alternatively connecting the transmission and the speed reducer to the motor shaft.
Claim 8
Dependent Claim
40 words
A mold clamping apparatus according to claim 5, wherein the transmission comprises a first gear connected to the motor shaft, a second gear meshing with the first gear and having a shaft detachably connected to the first ball screw shaft.
Claim 9
Dependent Claim
49 words
A mold clamping apparatus according to claim 6, wherein the speed reducer comprises a speed reducer gear meshing with the first gear, a splined shaft detachably connected to the second ball screw shaft and supporting the speed reducer gear and being axially movable relative to the speed reducer gear.
Claim 10
Dependent Claim
55 words
A mold clamping apparatus according to claim 7, wherein the switching means comprises: a first clutch between the first ball screw shaft and the second gear shaft, and a second clutch between the second ball screw shaft and the splined shaft, and a controller for alternatively outputting switching signals to the first and second clutches.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-11-05 | 1994-05-07 | 1994-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-05 | 1998-05-07 | 1998-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-05 | 2002-05-07 | 2002-11-06 | $7700.00 | Window Closed / Lapsed |