US3575074A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus to control the feeding amount in bandsawing machines
Assignee: Amada Co Ltd
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Filing: 1968-03-06
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Granted: 1971-04-13
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Expires: 1988-03-06
Abstract
Abstract Apparatus to control the feeding amount in hydraulically controlled band sawing machines having a pivotable frame which supports the bandsaw, and a hydraulic cylinder for lifting and lowering the frame with respect to the material to be cut, comprising a hydraulic pressure control means for the cylinder, valve means (preferably with a knife-edge shaped outlet) for controlling the quantity of hydraulic fluid reaching the cylinder, and at least one hydraulic connection, namely between the outlet of the control means and the inlet of the valve means.
Inventors
- 👤 Tsuneo Aizawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:31
CPC Classifications
B; B23; B23D; B23D55/00; B23D55/08; B23D55/088; B23D55/089; B23D53/00; B23D53/04; B23D53/045; Y; Y10; Y10T; Y10T83/00; Y10T83/04; Y10T83/707; Y10T83/7101; Y10T83/7114; Y10T83/869; Y10T83/8748; Y10T83/8749
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
207 words
An apparatus to control the feeding amount in a hydraulically controlled band sawing machine, the latter having a pivotable frame supporting a band saw adapted operatively to engage a stationary material to be cut, and a hydraulic cylinder for selectively lifting and lowering a portion of said frame so as to pivot the same with respect to the material, the apparatus comprising, in combination, hydraulic pressure control means for said cylinder, valve means cooperating with said cylinder and controlling the quantity of the adjusted hydraulic fluid flowing through said valve means, the latter having an outlet with a knife-edge shape, a first hydraulic connection between the outlet of said cylinder and the inlet of said pressure control means, and a second hydraulic connection between the outlet of said pressure control means and the inlet of said valve means, wherein said pressure control means includes a spring-biased piston with at least one passage therein for the hydraulic fluid, which is narrowed in cross section as the action of said cylinder is accelerated upon decrease of the cutting resistance and upon increase of the cutting-in speed, and vice versa, thus maintaining the pressure of the hydraulic fluid at a constant value when the same leaves said pressure control means.
Claim 2
Independent Claim
207 words
An apparatus to control the feeding amount in a hydraulically controlled band sawing machine, the latter having a pivotable frame supporting a band saw adapted operatively to engage a stationary material to be cut, and a hydraulic cylinder for selectively lifting and lowering a portion of said frame so as to pivot the same with respect to the material, the apparatus comprising, in combination, hydraulic pressure control means for said cylinder, valve means cooperating with said cylinder and controlling the quantity of the adjusted hydraulic fluid flowing through said valve means, the latter having an outlet with a knife-edge shape, a first hydraulic connection between the outlet of said cylinder and the inlet of said pressure control means, and a second hydraulic connection between the outlet of said pressure control means and the inlet of said valve means, wherein said pressure control means includes a spring-biased piston with at least one passage therein for the hydraulic fluid, which is narrowed in cross section as the action of said cylinder is accelerated upon decrease of the cutting resistance and upon increase of the cutting-in speed, and vice versa, thus maintaining the pressure of the hydraulic fluid at a constant value when the same leaves said pressure control means.
Claim 3
Dependent Claim
41 words
The apparatus as defined in claim 1, wherein said passage of the piston is substantially transversal and communicates with a peripheral recessed clearance in said piston as well as with a longitudinal passage therein which leads to said second hydraulic connection.
Claim 4
Dependent Claim
34 words
The apparatus as defined in claim 1, further comprising a bypass for the hydraulic fluid from said outlet of the valve means to the side of said piston acted upon by its biasing spring.
Claim 5
Dependent Claim
31 words
The apparatus as defined in claim 1, wherein said valve means includes means for adjusting said outlet with the knife-edge shape with respect to a transversal passage in said valve means.
Claim 6
Dependent Claim
28 words
The apparatus as defined in claim 4, wherein said transversal passage of the valve means communicates with a longitudinal passage therein which leads to said second hydraulic connection.
Claim 7
Dependent Claim
82 words
The apparatus as defined in claim 1, further comprising a tank and propelling means for the hydraulic fluid, and means for providing an operative flow path for the hydraulic fluid from said cylinder to said tank by way of an inlet passage of said pressure control means, a recessed clearance in a spring-biased displaceable control member thereof, an axial passage in the latter, a clearance beyond said control member, followed by said second hydraulic connection and said valve means, and back again.
References Cited (Backward Citations)
US1390469A
Cited
US2601576A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-12 | 1974-10-12 | 1975-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-12 | 1978-10-12 | 1979-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-12 | 1982-10-12 | 1983-04-13 | $7700.00 | Window Closed / Lapsed |