US3597798A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two-stage clamping mechanism
Assignee: Milacron Inc
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Filing: 1970-03-20
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Granted: 1971-08-10
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Expires: 1990-03-20
Abstract
Abstract A hydraulically actuated two-stage clamping mechanism for moving a movable member into and out of cooperative relationship with a stationary member. A pair of rigid link arms is pivotally interconnected at one end of each of the arms to form a toggle which comprises the first stage of the mechanism. The free end of one of the toggle arms is pivotally connected to a stationary portion while the free end of the other arm is pivotally connected to a movable member. The pivotally interconnected ends of the toggle arms define a knee-type joint which incorporates an integral hydraulic rotary actuator which upon the application of hydraulic pressure, causes relative motion between the arms and thereby moves the movable member toward and away from the stationary member. The second stage of the mechanism is a large diameter, short travel clamping piston to firmly hold the movable and stationary members together. Additionally, adjustment means are provided to vary the initial spacing between the two stationary members.
Inventors
- 👤 David I Mcdonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:00
CPC Classifications
B; B29; B29C; B29C45/00; B29C45/17; B29C45/64; B29C45/68; B29C45/683; B29C45/1751; Y; Y10; Y10S; Y10S425/00; Y10S425/223
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
248 words
In a mold-clamping mechanism for moving a movable member carrying one part of a mold into engagement with a first stationary member carrying a second part of said mold, said movable member having a front and rear side and being connected through a link system to a second stationary member positioned on a base and facing the rear side of said movable member, said moving and stationary members having their principal faces substantially parallel, and said moving member being supported for linear movement toward and away from said first cooperating stationary member, the improvement comprising: a. a first link member having a first end and a second end spaced from said first end, said first end being pivotally attached to the rear side of said movable member; b. a second link member having a first end and second end spaced from said first end, said first end being pivotally attached to said second stationary member; c. said second end of said first link member being pivotally attached to said second end of said second link member to form a knee joint; d. a rotary hydraulic actuator positioned at said knee joint for applying oppositely directed torques to the ends of each of said links at said knee joint to thereby change the included angle between said links and thus move said movable member relative to said stationary members; and e. means for increasing the contact pressure between said mold parts to preclude separation thereof during the molding process.
Claim 2
Dependent Claim
248 words
In a mold-clamping mechanism for moving a movable member carrying one part of a mold into engagement with a first stationary member carrying a second part of said mold, said movable member having a front and rear side and being connected through a link system to a second stationary member positioned on a base and facing the rear side of said movable member, said moving and stationary members having their principal faces substantially parallel, and said moving member being supported for linear movement toward and away from said first cooperating stationary member, the improvement comprising: a. a first link member having a first end and a second end spaced from said first end, said first end being pivotally attached to the rear side of said movable member; b. a second link member having a first end and second end spaced from said first end, said first end being pivotally attached to said second stationary member; c. said second end of said first link member being pivotally attached to said second end of said second link member to form a knee joint; d. a rotary hydraulic actuator positioned at said knee joint for applying oppositely directed torques to the ends of each of said links at said knee joint to thereby change the included angle between said links and thus move said movable member relative to said stationary members; and e. means for increasing the contact pressure between said mold parts to preclude separation thereof during the molding process.
Claim 3
Dependent Claim
25 words
The clamping mechanism of claim 1 wherein said rotary hydraulic actuator is integral with said first and said second links and defines said knee joint.
Claim 4
Dependent Claim
153 words
The clamping mechanism of claim 2 wherein the second end of one of said links is attached to a cylindrical pivot which carries a pair of outwardly directed, substantially radially extending vanes and the second end of the other of said links is attached to a ring member concentric with said pivot, said ring member having an inner diameter greater than the outer diameter of said pivot, said vanes contacting the inner surface of said ring member, a pair of stops diametrically positioned on the inner surface of said ring member and extending inwardly to said pivot to define a pair of arcuate chambers therebetween and limit the relative rotation between said first and second links, and means for selectively introducing hydraulic fluid under pressure to either side of said vanes to cause said vanes to move relative to said stops and thereby impart relative rotation between said links about said knee joint.
Claim 5
Dependent Claim
18 words
The clamping mechanism of claim 3 wherein said hydraulic fluid is introduced through bores provided in said pivot.
Claim 6
Dependent Claim
26 words
The clamping mechanism of claim 4 wherein said vanes and said stops include spring-biased sealing means to prevent leakage of hydraulic fluid around the ends thereof.
Claim 7
Dependent Claim
33 words
The clamping mechanism of claim 2 wherein said pressure-increasing means comprises a hydraulic piston slidable within said second stationary member and having said first end of said second link member pivotally attached thereto.
Claim 8
Dependent Claim
22 words
The clamping mechanism of claim 6 including means for varying the spacing of said second stationary member from said first stationary member.
Claim 9
Dependent Claim
114 words
The clamping mechanism of claim 7 wherein said position varying means comprises: a. ways carried by said base upon which said second stationary member can move toward and away from said first stationary member; b. tie rods extending between said first and said second stationary members, said tie rods including external screw threads formed therein in the vicinity of said second stationary member; c. adjusting means positioned for movement along said screw threads; d. means carried by said second stationary member cooperable with said adjusting means; and e. means for moving said adjusting means along said screw threads, whereby to cause said secondary member to move toward or away from said first stationary member.
Claim 10
Dependent Claim
41 words
The clamping mechanism of claim 8 wherein said moving means comprises an endless chain which passes around sprocket members carried by said adjusting means to move each of said adjusting means an equal distance, and means for moving said endless chain.
Claim 11
Dependent Claim
17 words
The clamping mechanism of claim 9 including means for locking said moving means in any desired position.
References Cited (Backward Citations)
US3345691A
Cited
US3418692A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-09 | 1975-02-08 | 1975-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-09 | 1979-02-08 | 1979-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-09 | 1983-02-08 | 1983-08-10 | $7700.00 | Window Closed / Lapsed |