US3836743A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Localized heat treating machine
Assignee: Research Engineering and Manufacturing Inc
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Filing: 1974-01-21
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Granted: 1974-09-17
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Expires: 1994-01-21
Abstract
Abstract An article is hardened or tempered in a localized zone. Where the article is a thread-forming device the zone is that part of its thread that does the thread-forming in the workpiece. The hardness of the remainder of the body of the article is left unchanged. The localized hardening is carried out by a method that includes high frequency induction heating only of the zone followed by quenching of the zone whereby the hardened zone is a skin of predetermined depth. A machine for making articles in accordance with the method comprises means for delivering the articles in succession to an induction heating element, a mechanism for advancing the articles through the heating element for progressive heating of the surface of the article in the localized zone to a predetermined depth, a quenching manifold for applying a spray of quenching liquid to the heated articles from the heating element and conveying them to the quenching manifold.
Inventors
- 👤 C Wardwell
- 👤 N Holcomb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:42
CPC Classifications
C; C21; C21D; C21D1/00; C21D1/34; C21D1/42; Y; Y02; Y02P; Y02P10/00; Y02P10/25
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
213 words
A machine for heat-treating elongated articles in a localized peripheral zone that is a fractional part of the length of the article and which envelopes a core of the article, comprising an induction heater, said heater having spaced bars, means for suspending said articles between said bars so that said localized zone is adjacent to said bars and said articles are sufficiently closely spaced to be inductively coupled for complete peripheral heating in said zone, means for feeding said articles through said induction heater, means for quenching in succession each article in said peripheral zone, means for conveying the heated articles in succession to the quenching means, and wherein the lengths of the bars are such that a plurality of articles can be supported between said bars by said suspending means with the articles running substantially perpendicular to the general plane defined by said bars and with the articles extending beyond said general plane, said means for feeding said articles through said induction heater cooperating with said means for conveying the heated articles to the quenching means to feed an article to an initial induction heating position between said bars and at the same time discharge another article from a final heating position from between said bars for conveyance to said quenching means.
Claim 2
Dependent Claim
213 words
A machine for heat-treating elongated articles in a localized peripheral zone that is a fractional part of the length of the article and which envelopes a core of the article, comprising an induction heater, said heater having spaced bars, means for suspending said articles between said bars so that said localized zone is adjacent to said bars and said articles are sufficiently closely spaced to be inductively coupled for complete peripheral heating in said zone, means for feeding said articles through said induction heater, means for quenching in succession each article in said peripheral zone, means for conveying the heated articles in succession to the quenching means, and wherein the lengths of the bars are such that a plurality of articles can be supported between said bars by said suspending means with the articles running substantially perpendicular to the general plane defined by said bars and with the articles extending beyond said general plane, said means for feeding said articles through said induction heater cooperating with said means for conveying the heated articles to the quenching means to feed an article to an initial induction heating position between said bars and at the same time discharge another article from a final heating position from between said bars for conveyance to said quenching means.
Claim 3
Dependent Claim
54 words
A machine according to claim 1 including a raceway for containing a plurality of said articles, said raceway terminating adjacent to said bars for delivery of articles to said feeding means, said feeding means comprising means engageable with the articles delivered thereto by said raceway, and said conveying means comprises a rotatable feed wheel.
Claim 4
Dependent Claim
174 words
A machine for heat-treating screws each having a head and a peripherally threaded shank with a localized zone of the thread being of a type for producing a thread in a workpiece: comprising an induction heater having means forming a region with a high frequency alternating current field, means for feeding said screws substantially non-rotatably through said field and such that said shanks are similarly oriented in said field and are sufficiently closely spaced side-by-side to be inductively coupled for heating at said zones circumferentially therearound at least to a tempering temperature while leaving substantially unheated the cores of the shanks that are surrounded by said zones, said induction heater being of such extent relative to the axial extent of said shanks that said zones are adjacent to said heater and said shanks extend beyond said heater thereby to leave substantially unheated the shanks remote from said zones, means by which said screws are withdrawn from said heater, and means for supporting said screws at their heads as they are fed through said field.
Claim 5
Dependent Claim
174 words
A machine for heat-treating screws each having a head and a peripherally threaded shank with a localized zone of the thread being of a type for producing a thread in a workpiece: comprising an induction heater having means forming a region with a high frequency alternating current field, means for feeding said screws substantially non-rotatably through said field and such that said shanks are similarly oriented in said field and are sufficiently closely spaced side-by-side to be inductively coupled for heating at said zones circumferentially therearound at least to a tempering temperature while leaving substantially unheated the cores of the shanks that are surrounded by said zones, said induction heater being of such extent relative to the axial extent of said shanks that said zones are adjacent to said heater and said shanks extend beyond said heater thereby to leave substantially unheated the shanks remote from said zones, means by which said screws are withdrawn from said heater, and means for supporting said screws at their heads as they are fed through said field.
Claim 6
Dependent Claim
15 words
A machine according to claim 3 including means for quenching said screws at said zones.
Claim 7
Dependent Claim
45 words
A machine according to claim 3 including a raceway for receiving said screws as they are withdrawn from said heater, said raceway including means for slidably supporting the heads of said screws, said last-named means forming a gap for receiving the shanks of said screws.
Claim 8
Dependent Claim
36 words
A machine according to claim 3 in which said heating element comprises spaced bars between which said screws move and with the shanks of said screws being perpendicular to a general plane defined by said bars.
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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) | 1977-09-16 | 1978-03-18 | 1978-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-16 | 1982-03-18 | 1982-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-16 | 1986-03-18 | 1986-09-17 | $7700.00 | Window Closed / Lapsed |