Patent US4147335A successfully refreshed from Google Patents.
US4147335A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for hardening the cam tracks of camshafts for internal combustion engines
Assignee: Audi AG
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Filing: 1978-01-27
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Granted: 1979-04-03
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Expires: 1998-01-27
Abstract
Abstract An apparatus for hardening the cam tracks of camshafts in which one or more camshafts to be hardened are mounted adjacent a master camshaft for synchronous rotation therewith. A plurality of burners are slidably mounted adjacent each track to be hardened for movement toward and away from the track. A follower on the corresponding track of the master camshaft controls movement of the burner. An eccentric oscillates a plate on which the camshafts are mounted to cover all of the cam track. The burner is turned on and off so that the zone of the cam base circle is not heated and remains unhardened.
Inventors
- 👤 Klaus Heck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:36
CPC Classifications
C; C21; C21D; C21D9/00; C21D9/30
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
240 words
An apparatus for hardening, without quenching, the cam tracks of a camshaft for internal combustion engines comprising: a frame; means mounted on said frame for mounting for rotation a camshaft to be hardened; a master camshaft having at least one cam track of substantially the same shape and orientation as the cam track of said camshaft to be hardened; means for mounting for rotation adjacent to said camshaft to be hardened said master camshaft; means for synchronously rotating said camshaft to be hardened and said master camshaft; at least one arc-remelting burner for heating a corresponding cam track of said camshaft to be hardened; means, connected to said at least one burner and responsive to the rotational orientation of said master camshaft, for mounting said at least one burner for movement toward and away from said corresponding cam track such that at all times said at least one burner is maintained at a uniform distance from the surface of said corresponding cam track; means for moving said camshaft rotational mounting means axially of said at least one camshaft to be hardened such that during rotation of said camshafts, said camshaft to be hardened oscillates axially with an amplitude substantially equal to the width of said corresponding cam tracks and with a frequency which may be tuned relatively to the angular rotational velocity of the camshafts in conformity with the physical dimensions and performance criteria of the camshaft to be hardened.
Claim 2
Independent Claim
240 words
An apparatus for hardening, without quenching, the cam tracks of a camshaft for internal combustion engines comprising: a frame; means mounted on said frame for mounting for rotation a camshaft to be hardened; a master camshaft having at least one cam track of substantially the same shape and orientation as the cam track of said camshaft to be hardened; means for mounting for rotation adjacent to said camshaft to be hardened said master camshaft; means for synchronously rotating said camshaft to be hardened and said master camshaft; at least one arc-remelting burner for heating a corresponding cam track of said camshaft to be hardened; means, connected to said at least one burner and responsive to the rotational orientation of said master camshaft, for mounting said at least one burner for movement toward and away from said corresponding cam track such that at all times said at least one burner is maintained at a uniform distance from the surface of said corresponding cam track; means for moving said camshaft rotational mounting means axially of said at least one camshaft to be hardened such that during rotation of said camshafts, said camshaft to be hardened oscillates axially with an amplitude substantially equal to the width of said corresponding cam tracks and with a frequency which may be tuned relatively to the angular rotational velocity of the camshafts in conformity with the physical dimensions and performance criteria of the camshaft to be hardened.
Claim 3
Dependent Claim
31 words
An apparatus as in claim 1, further including means for turning said burner on and off during said rotation so that the zone of the cam base circle is not heated.
Claim 4
Dependent Claim
57 words
An apparatus as in claim 1, wherein: said camshaft to be hardened mounting means includes a rotating clamp, a base plate mounted on said clamp and slidably mounted for movement in the axial direction of said camshafts and said means for moving said camshaft rotational mounting means axially comprises an eccentric drive coupled to said rotating means.
Claim 5
Dependent Claim
15 words
An apparatus as in claim 1, including means for preheating said camshaft to be hardened.
Claim 6
Dependent Claim
18 words
An apparatus as in claim 1 including means for mounting a plurality of said camshafts to be hardened.
Claim 7
Dependent Claim
69 words
An apparatus as in claim 1, wherein said means for mounting said at least one burner comprises: guideways mounted on said frame and oriented for sliding a slide toward and away from said corresponding cam track; a slide mounted to said at least one burner and arranged to slide on said guideways; and cam follower means attached to said slide for following the cam profile of said master camshaft.
Claim 8
Dependent Claim
40 words
An apparatus as in claim 6 wherein: said at least one burner comprises one corresponding burner for each cam track of said camshaft to be hardened; and said apparatus further comprises one said burner mounting means for each said burner.
Claim 9
Dependent Claim
178 words
An apparatus as in claim 1 further comprising: means for mounting a plurality of approximately identical camshafts to be hardened in juxtaposed position, said plurality mounting means including: clamp means including work drivers for rotatably clamping each of said plurality of camshafts to be hardened in juxtaposed position; and a single base plate mounted on said camshaft clamp means and slideably mounted on said frame for movement in the axial direction of said plurality of camshafts to be hardened, so that said plate, clamps and camshafts to be hardened, may be oscillated in unison; and a plurality of arc remelting burners corresponding to a different cam track of each camshaft to be hardened; said work drivers being rotationally oriented one from another in accordance with the offset angle of one said cam track relative to another said cam track so that a different cam track of each camshaft to be hardened is maintained at a uniform distance from said corresponding burner; each said corresponding burner being mounted on said slide and said plurality mounting means being synchronously driven.
Claim 10
Dependent Claim
178 words
An apparatus as in claim 2 further comprising: means for mounting a plurality of approximately identical camshafts to be hardened in juxtaposed position, said plurality mounting means including: clamp means including work drivers for rotatably clamping each of said plurality of camshafts to be hardened in juxtaposed position; and a single base plate mounted on said camshaft clamp means and slideably mounted on said frame for movement in the axial direction of said plurality of camshafts to be hardened, so that said plate, clamps and camshafts to be hardened, may be oscillated in unison; and a plurality of arc remelting burners corresponding to a different cam track of each camshaft to be hardened; said work drivers being rotationally oriented one from another in accordance with the offset angle of one said cam track relative to another said cam track so that a different cam track of each camshaft to be hardened is maintained at a uniform distance from said corresponding burner; each said corresponding burner being mounted on said slide and said plurality mounting means being synchronously driven.
Claim 11
Dependent Claim
178 words
An apparatus as in claim 6 further comprising: means for mounting a plurality of approximately identical camshafts to be hardened in juxtaposed position, said plurality mounting means including: clamp means including work drivers for rotatably clamping each of said plurality of camshafts to be hardened in juxtaposed position; and a single base plate mounted on said camshaft clamp means and slideably mounted on said frame for movement in the axial direction of said plurality of camshafts to be hardened, so that said plate, clamps and camshafts to be hardened, may be oscillated in unison; and a plurality of arc remelting burners corresponding to a different cam track of each camshaft to be hardened; said work drivers being rotationally oriented one from another in accordance with the offset angle of one said cam track relative to another said cam track so that a different cam track of each camshaft to be hardened is maintained at a uniform distance from said corresponding burner; each said corresponding burner being mounted on said slide and said plurality mounting means being synchronously driven.
References Cited (Backward Citations)
US1768160A
Cited
US2085790A
Cited
US2215576A
Cited
US2242158A
Cited
US2290283A
Cited
US2665126A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-04-02 | 1982-10-02 | 1983-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-02 | 1986-10-02 | 1987-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-02 | 1990-10-02 | 1991-04-03 | $7700.00 | Window Closed / Lapsed |