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US3942345A Expired / Lapsed US ⏱️ 0.0 years remaining

Key operated magnetic tumbler lock

Assignee: JAPAN MAGNETIC LOCK CO Ltd
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Filing: 1974-11-04
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Granted: 1976-03-09
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Expires: 1994-11-04
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Abstract

Abstract A key operated locking device of the type using a coded magnetic key to operate a plurality of correspondingly coded magnetic tumblers. The device serves to selectively lock and unlock relative rotation between inner and outer coaxial cylinders in which the inner cylinder has a keyway disposed therein for receiving the magnetically coded key and also carries a plurality of spring-biased magnetic tumblers which magnetically interact with the key. The outer cylinder is provided with a plurality of detents cooperating with the magnetic tumblers wherein the tumblers are normally spring-biased into engagement with the detents of the outer cylinder and are unlocked therefrom by inserting a properly coded magnetic key into the inner cylinder keyway to withdraw in concert the tumblers from the detents by magnetic attraction. With the key in place the inner cylinder may then be rotated relative to the outer cylinder, while the magnetic attraction continuously maintains the tumblers in a recessed or condition inside the inner cylinder.

Inventors

  • 👤 Takashi Sasahara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 12:01
CPC Classifications
E; E05; E05B; E05B47/00; E05B47/0038; E05B47/0044; Y; Y10; Y10T; Y10T70/00; Y10T70/70; Y10T70/7051; Y10T70/7057; Y10T70/7441; Y10T70/7486; Y10T70/7508; Y10T70/7559; Y10T70/7565

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 299 words
In a key operated magnetic tumbler lock of the type including an outer hollow cylinder, an inner cylinder mated for coaxial relative rotation inside said outer cylinder and having an elongate keyway extending substantially parallel to the axis of said inner cylinder, a plurality of magnetic tumbler assemblies carried in said inner cylinder and a corresponding plurality of cooperating detents provided on an inner surface of said outer cylinder for selectively locking and unlocking said relative rotation therebetween, and a key carrying a plurality of magnetic members for insertion in said keyway for magnetically causing the disengagement of said associated magnetic tumbler assemblies and cooperating detents to unlock said cylinders, the improvement comprising: elongate tumbler receiving guides disposed in said inner cylinder and extended transversely to and in juxtaposition with said keyway; said magnetic tumbler assemblies each including a magnetic tumbler and biasing spring mounted in individual ones of said tumbler guides for longitudinal slideable reciprocation of said tumblers between a protracted condition engaging said detents and a retracted condition juxtaposed said keyway, said biasing springs continuously urging said tumblers toward said protracted condition, said magnetic tumblers each defining a magnetic polar axis and being disposed with said polar axes substantially longitudinally aligned with the longitudinal dimension of said guides; said detents being provided on an inner surface of said outer hollow cylinder in cooperating registration with said tumblers in their protracted condition for locking said relative rotation of said cylinders; and said members of said key each defining a magnetic polar axis and being oriented such that when said key has been inserted in said keyway said members are disposed with their polar axes in substantial parallel juxtaposition and in polar opposition to the polar axes of said tumblers to slideably withdraw said tumblers to said retracted condition.
Claim 2
Dependent Claim 299 words
In a key operated magnetic tumbler lock of the type including an outer hollow cylinder, an inner cylinder mated for coaxial relative rotation inside said outer cylinder and having an elongate keyway extending substantially parallel to the axis of said inner cylinder, a plurality of magnetic tumbler assemblies carried in said inner cylinder and a corresponding plurality of cooperating detents provided on an inner surface of said outer cylinder for selectively locking and unlocking said relative rotation therebetween, and a key carrying a plurality of magnetic members for insertion in said keyway for magnetically causing the disengagement of said associated magnetic tumbler assemblies and cooperating detents to unlock said cylinders, the improvement comprising: elongate tumbler receiving guides disposed in said inner cylinder and extended transversely to and in juxtaposition with said keyway; said magnetic tumbler assemblies each including a magnetic tumbler and biasing spring mounted in individual ones of said tumbler guides for longitudinal slideable reciprocation of said tumblers between a protracted condition engaging said detents and a retracted condition juxtaposed said keyway, said biasing springs continuously urging said tumblers toward said protracted condition, said magnetic tumblers each defining a magnetic polar axis and being disposed with said polar axes substantially longitudinally aligned with the longitudinal dimension of said guides; said detents being provided on an inner surface of said outer hollow cylinder in cooperating registration with said tumblers in their protracted condition for locking said relative rotation of said cylinders; and said members of said key each defining a magnetic polar axis and being oriented such that when said key has been inserted in said keyway said members are disposed with their polar axes in substantial parallel juxtaposition and in polar opposition to the polar axes of said tumblers to slideably withdraw said tumblers to said retracted condition.
Claim 3
Dependent Claim 47 words
The improved key operated magnetic tumbler lock of claim 1, wherein said inner cylinder has a plurality of elongate slots formed therein to provide said guides, the longitudinal dimension of said slots extending substantially at right angles to the axis of said inner cylinder adjacent said keyway.
Claim 4
Dependent Claim 116 words
The improved key operated magnetic tumbler lock of claim 1, wherein said keyway extends substantially centrally of said inner cylinder and said inner cylinder has a plurality of elongate slots extending substantially transversely to and offset from the axis of said inner cylinder adjacent said keyway to provide said tumbler guides, each said slot opening at one end at an exterior surface of said inner cylinder for receiving a tumbler assembly and having an abutment formed at an opposite end for retaining said biasing spring in compression between said abutment and said magnetic tumbler, whereby said biasing springs of said tumbler assemblies continuously urge associated said tumblers to said protracted conditions for engaging said outer detents.
Claim 5
Dependent Claim 68 words
The improved key operated magnetic tumbler lock of claim 1, wherein said magnetic members of said key and said magnetic tumblers of said tumbler assemblies are arranged such that when said key has been inserted in said keyway and said magnetic tumblers have assumed said retracted condition the magnetic poles of associated said magnetic tumblers and magnetic members produce magnetic field lines that substantially close on each other.
Claim 6
Dependent Claim 95 words
The improved key operated magnetic tumbler lock of claim 1, wherein said keyway defines a transverse substantially rectangular cross section of major and minor dimensions with said major dimension extending substantially diametrically of said inner cylinder, said inner cylinder having a plurality of elongate slots providing said tumbler guides, each of said slots extending substantially at right angles to the axis of said inner cylinder and in juxtaposition with at least one of the major dimension sides of said keyway, said magnetic tumblers of said tumbler assemblies being longitudinally, slideably disposed in said elongate slots.
Claim 7
Dependent Claim 240 words
The improved key operated magnetic tumbler lock of claim 1, wherein: said tumbler receiving guides comprise a plurality of elongate slots extending substantially transversely through said inner cylinder to define slot openings on substantially opposed exterior surfaces of said inner cylinder; said magnetic tumblers being elongate and slideably mounted in said slots for bidirectional reciprocation therein between a retracted condition in which opposed axial ends of said tumblers are substantially flush with the exterior surface of said inner cylinder and alternate protracted conditions in which one and then the other of the axial ends of said tumblers protrudes from said inner cylinder surface; means mounting said biasing springs in said guide means for continuously urging said tumblers to said protracted condition with one of the axial ends thereof protruding from said inner cylinder exterior surface for cooperating with said detents; additional detents provided on said inner surface of said outer cylinder opposed to said first named detents and cooperating with the other axial ends of said tumblers; and said magnetic tumblers each having a magnetic member mounted along the length thereof and oriented with the magnetic poles thereof causing mutual attraction between an associated magnetic member of said key, said associated tumbler and key magnetic member being selectively positioned relative to one another to cause said elongate tumblers to slideably assume said retracted condition as said magnetic tumbler self aligns itself by magnetic attraction with the associated key magnetic member.
Claim 8
Dependent Claim 58 words
The improved key operated magnetic tumbler lock of claim 6, wherein said keyway defines a transverse substantially rectangular cross section of major and minor dimensions with said major dimension extending substantially diametrically of said inner cylinder, said elongate slots disposed substantially parallel to and in juxtaposition with at least one of the major dimension sides of said keyway.
Claim 9
Dependent Claim 107 words
The improved key operated magnetic tumbler lock of claim 7, wherein said biasing springs are elongate compression springs and said means mounting said springs include an elongate spring receiving slot longitudinally juxtaposed each of said guide slots and of lesser longitudinal dimension than said guide slots, each said spring receiving slots terminating at one end in an abutment, each said tumbler having a lateral foot disposed intermediate the ends thereof, and said biasing springs being mounted in said spring receiving slots longitudinally juxtaposed to said guide slots and in compression between said abutment and foot to urge one axial end of said tumblers toward said protracted condition.
Claim 10
Dependent Claim 196 words
A key operated magnetic tumbler lock comprising: inner and outer relatively rotatable coaxially disposed cylinder means; coded magnetic tumbler means slideably mounted in tumbler receiving openings provided in said inner cylinder means, each said tumbler means having magnetic poles defining a polar axis; detent means provided on said outer cylinder means for cooperating with said tumbler means for selectively locking and unlocking said relative rotation between said cylinder means; keyway means provided in said inner cylinder means in juxtaposition with said tumbler receiving openings; and coded magnetic key means mated for insertion in said keyway means and having magnetic means defining a plurality of polar axes oriented such that when said key means has been inserted in said keyway means said polar axes of said key means are disposed in parallel juxtaposition and in polar opposition with said polar axes of said tumbler means for causing conserted magnetic attraction between said coded key means and said tumbler means to slide said tumbler means into juxtaposition with said magnetic means of said key means, whereby said tumbler means are withdrawn from said detent means to unlock said inner and outer cylinder means for allowing relative rotation therebetween.
Claim 11
Dependent Claim 196 words
A key operated magnetic tumbler lock comprising: inner and outer relatively rotatable coaxially disposed cylinder means; coded magnetic tumbler means slideably mounted in tumbler receiving openings provided in said inner cylinder means, each said tumbler means having magnetic poles defining a polar axis; detent means provided on said outer cylinder means for cooperating with said tumbler means for selectively locking and unlocking said relative rotation between said cylinder means; keyway means provided in said inner cylinder means in juxtaposition with said tumbler receiving openings; and coded magnetic key means mated for insertion in said keyway means and having magnetic means defining a plurality of polar axes oriented such that when said key means has been inserted in said keyway means said polar axes of said key means are disposed in parallel juxtaposition and in polar opposition with said polar axes of said tumbler means for causing conserted magnetic attraction between said coded key means and said tumbler means to slide said tumbler means into juxtaposition with said magnetic means of said key means, whereby said tumbler means are withdrawn from said detent means to unlock said inner and outer cylinder means for allowing relative rotation therebetween.

References Cited (Backward Citations)

US2079628A Cited
DE1036702B Cited
US3566637A Cited
US3657907A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-03-09 1979-09-08 1980-03-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-03-09 1983-09-08 1984-03-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-03-09 1987-09-08 1988-03-09 $7700.00 Window Closed / Lapsed

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