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US 5,630,331 AGranted
Key cylinder automatic returning device for cylinder lock device
AssigneeAlpha Corporation
InventorKeiichi Miyamoto
Life of this patent
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AssigneeAlpha Corporation
InventorKeiichi Miyamoto
Estimating the term…
A cylinder shaft projects from a key cylinder along the center line of a sleeve, and first and second case shafts project from a case. A spring is coiled on the first case shaft, and the cylinder shaft is placed between the first and second case shafts. The cylinder shaft and the second case shaft are placed between both legs of the spring. When the key cylinder is rotated with respect to the sleeve by the proper key being inserted in the key cylinder, the spring imparts returning force to the cylinder shaft that is making an arcuate movement in a circular-arc groove formed in the case.
A key cylinder lock and key cylinder automatic returning device comprising:
A key cylinder lock and key cylinder automatic returning device comprising:
A key cylinder lock and key cylinder automatic returning device comprising:
Dependencies are inferred from the claim text.
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No related US applications are recorded in the indexed filing history.
Accessories in connection with locks: devices for coupling the turning cylinder of a single or a double cylinder lock with the bolt operating member
Fraction or shear lines; Slip-clutches, resilient parts or the like for preventing damage when forced or slammed: with non-destructive disengagement
Casings of cylinder locks: means for returning cylinder locks to their neutral position
Wound springs: wound in a plane, e.g. spirally
Term ended 28 Apr 2015 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
The present invention relates to a cylinder lock device and, more particularly, to a cylinder lock with high resistance to destruction, and in which a rotated key cylinder is automatically returned to the original position by a spring.
In conventional cylinder locks, the proper key can be rotated to the locked position or the unlocked position in a key cylinder provided with tumblers that engage with a groove formed in a case. However, in such a conventional cylinder lock which prevents rotation of the key cylinder by means of the tumblers that are engaged with the groove of the case, there is a possibility that the cylinder lock is locked by destroying the tumblers. To solve this problem, as disclosed in, for instance, Japanese Unexamined Patent Publication No. Hei. 1-315569, a free-turn cylinder lock has been proposed in which a key cylinder is freely rotated when it is given rotational force in an illegal unlocking attempt. This type of cylinder lock has a sleeve rotatably incorporated in a case and the key cylinder rotatably supported in a second housing of a sleeve.
When the proper key is inserted into the key cylinder, the tumblers in the key cylinder are disengaged from the groove formed in the sleeve, to allow the key cylinder to be rotated relative to the sleeve. As a result, a slide ring engages with a lock-piece operating member and it becomes possible to actuate a lock device.
FIG. 1 is a sectional view showing a key cylinder automatic returning device for a cylinder lock device according to a first embodiment of the present invention;
FIG. 2 is a rear view of the device of FIG. 1;
FIG. 3 is a sectional view showing a key cylinder automatic returning device for a cylinder lock device according to a second embodiment of the invention;
Key cylinder automatic returning devices for a cylinder lock device according to embodiments of the present invention will be hereinafter described with reference to FIGS. 1-11.
As shown in FIG. 1, a cylinder lock device 1 according to a first embodiment of the invention has a case 3 provided with a first housing 7, a sleeve 4 that is rotatably incorporated in the first housing 7 of the case 3 and provided with a second housing 8, and a key cylinder 5 rotatably installed in the second housing 8 of the sleeve 4. As illustrated in FIG. 2, a circular-arc groove 16 is formed in the case 3. Tumblers (not shown) such as disk tumblers or pin tumblers are slidably arranged in the key cylinder 5 by the known method. The tumblers are engaged with an engaging portion that is, for instance, tumbler grooves or pin holes of the sleeve 4 so as to be separable therefrom.
A key cylinder automatic returning device 2 of this cylinder lock device 1 is provided with a cylinder shaft 15 that projects from the key cylinder 5 along the central axis 20 of the sleeve 4 passing through the circular-arc groove 16 of the case 3, and a pair of case shafts 13a and 13b that project from the case 3. A spring 10 is coiled on the case shaft 13a. The cylinder shaft 15 is so disposed as to be closer to the case shaft 13a than the case shaft 13b. The cylinder shaft 15 and the case shaft 13b are placed between both legs 11 and 12 of the spring 10. A lever 31 that is rotatably supported by a through-hole 30 is fixed to the case shaft (pivot) 13a with a clip or the like (not shown). The lever 31 has a through-hole 33 into which the cylinder shaft 15 is inserted and an arm 32 for driving a lock device (not shown).