US3728823A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thread grinding machine
Assignee: Toyoda Koki KK
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Filing: 1971-04-29
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Granted: 1973-04-24
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Expires: 1991-04-29
Abstract
Abstract A thread grinding machine is provided with a head stock and a tail stock in opposing relation and a spindle for supporting one end of a workpiece to be thread ground is rotatably and axially slidably mounted on fluid bearings in the head stock being threadably engaged with a feed screw shaft secured to the head stock. Rotation of the spindle causes a simultaneous axial sliding movement thereof to grind a helical form in the workpiece. A holding shaft for supporting the other end of the workpiece is mounted on fluid bearings for slidable movement axially in the tall stock and is urged toward the head stock under a constant force sufficient to rotatably support the workpiece.
Inventors
- 👤 T Tomita
- 👤 K Unno
- 👤 A Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 06:32
CPC Classifications
B; B23; B23G; B23G1/00; B23G1/36; B23G1/38; B24; B24B; B24B19/00; B24B19/02; B24B19/022; Y; Y10; Y10T; Y10T409/00; Y10T409/30; Y10T409/300056; Y10T409/300672
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
167 words
A grinding machine for grinding a workpiece comprising: a bed; a table mounted on said bed; a head stock and a tailstock mounted in opposing relation on said table for supporting said workpiece; a grinding wheel support mounted on said bed for movement toward and away from said workpiece; a spindle for supporting one end of said workpiece; fluid bearing means for rotatably and axially slidably supporting said spindle in one of said head stock and said tailstock; means for rotating said spindle; means non-rotatably secured to said one of said head stock and said tailstock and being threadably engaged with said spindle for axially sliding said spindle therein upon rotation thereof by said rotating means; means for transmitting rotation of said spindle to said workpiece; means slidably mounted in the other of said head stock and said tailstock for supporting the other end of said workpiece; and means for urging said workpiece other end supporting means toward said one of said head stock and said tailstock.
Claim 2
Dependent Claim
167 words
A grinding machine for grinding a workpiece comprising: a bed; a table mounted on said bed; a head stock and a tailstock mounted in opposing relation on said table for supporting said workpiece; a grinding wheel support mounted on said bed for movement toward and away from said workpiece; a spindle for supporting one end of said workpiece; fluid bearing means for rotatably and axially slidably supporting said spindle in one of said head stock and said tailstock; means for rotating said spindle; means non-rotatably secured to said one of said head stock and said tailstock and being threadably engaged with said spindle for axially sliding said spindle therein upon rotation thereof by said rotating means; means for transmitting rotation of said spindle to said workpiece; means slidably mounted in the other of said head stock and said tailstock for supporting the other end of said workpiece; and means for urging said workpiece other end supporting means toward said one of said head stock and said tailstock.
Claim 3
Dependent Claim
164 words
A thread grinding machine for grinding a workpiece comprising: a bed; a table mounted on said bed; a head stock and a tailstock mounted on said table in opposing relation for supporting said workpiece to be thread ground; a grinding wheel support mounted on said bed for movement toward and away from said workpiece; first fluid bearing means provided in said head stock; a spindle rotatably and axially slidably mounted in said first fluid bearing means for supporting one end of said workpiece; a feed screw shaft secured to said head stock and being threadedly engaged with said spindle; drive means for rotating said spindle; means mounted on said spindle for transmitting rotation of said spindle to said workpiece; second fluid bearing means provided in said tailstock; a holding shaft slidably mounted in said second fluid bearing means for supporting the other end of said workpiece; and hydraulic actuator means provided in said tailstock for selectively urging said holding shaft toward said head stock.
Claim 4
Dependent Claim
164 words
A thread grinding machine for grinding a workpiece comprising: a bed; a table mounted on said bed; a head stock and a tailstock mounted on said table in opposing relation for supporting said workpiece to be thread ground; a grinding wheel support mounted on said bed for movement toward and away from said workpiece; first fluid bearing means provided in said head stock; a spindle rotatably and axially slidably mounted in said first fluid bearing means for supporting one end of said workpiece; a feed screw shaft secured to said head stock and being threadedly engaged with said spindle; drive means for rotating said spindle; means mounted on said spindle for transmitting rotation of said spindle to said workpiece; second fluid bearing means provided in said tailstock; a holding shaft slidably mounted in said second fluid bearing means for supporting the other end of said workpiece; and hydraulic actuator means provided in said tailstock for selectively urging said holding shaft toward said head stock.
Claim 5
Dependent Claim
84 words
A thread grinding machine as set forth in claim 2, wherein said first and second fluid bearing means each comprises a pair of spaced fluid bearings; each bearing having a plurality of bearing pockets spaced at substantially equal intervals about the inner circumference thereof; each bearing being connected to a fluid pressure supply through a restrictor; and groove means provided in the inner circumference of each bearing for exhausting pressure fluid passing through said pockets and the clearance between each bearing and said spindle.
Claim 6
Dependent Claim
31 words
A thread grinding machine as set forth in claim 2, further comprising means for clamping said rotation transmitting means on said spindle in a desired angular position relative to said spindle.
Claim 7
Dependent Claim
123 words
A thread grinding machine as set forth in claim 2, wherein said drive means comprises: a hydraulic cylinder; a piston slidably received in said cylinder and having a piston rod thereon; means connecting said piston and said spindle for rotating said spindle in response to movement of said piston in said cylinder; a fluid pressure supply; and fluid control circuit means between said supply and the opposite sides of said hydraulic cylinder for selectively supplying fluid pressure to one side of said cylinder while simultaneously exhausting fluid from the other side for moving said piston in one direcTion and supplying fluid pressure to the other side of said cylinder while exhausting fluid from one side for moving said piston in the opposite direction.
Claim 8
Dependent Claim
30 words
A thread grinding machine as set forth in claim 5, wherein said hydraulic cylinder is provided with an adjustable stop member for permitting adjustment of the stroke of said piston.
Claim 9
Dependent Claim
95 words
A thread grinding machine as set forth in claim 5, wherein said fluid control circuit means comprises: a first throttle in a first fluid communication path between said supply and said one side of said hydraulic cylinder; a check valve in a second fluid communication path parallel with said first fluid communication path; a second throttle less restrictive than said first throttle in a third fluid communication path parallel with said first fluid communication path; and a change over valve in said third fluid communication path for selectively shutting off said third fluid communication path.
References Cited (Backward Citations)
US2371685A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-23 | 1976-10-23 | 1977-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-23 | 1980-10-23 | 1981-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-23 | 1984-10-23 | 1985-04-24 | $7700.00 | Window Closed / Lapsed |