Cylinder lock assembly

A cylinder lock includes a rotor rotatably mounted in a bore of a stationary casing. A key passage in the rotor is blocked by a biased shutter which is caused to pivot against the action of a spring when a key is introduced into the key passage. The rotor includes a plurality of separated, spring-urged tumblers which engage with the key in the key passage. A soft-elastic wiper for removing water from the key is positioned in a lateral slot between the entrance of the key passage and a first tumbler. Flaps of the wiper form a normally closed slit which is openable by the force of the key when the key is advanced towards an operational position.

This invention concerns broadly with improvements in and relating to 
cylinder locks, each using a mechanical key, and having at least part of 
the cylinder lock, especially the front part thereof, being exposed in its 
usage to ambient atmosphere containing aqueous moisture, fog, rain drops 
or the like. 
The inventive cylinder locks may be applied to automotive vehicle doors and 
trunk lids, although the invention is not limited to apply only thereto. 
As is commonly known, conventional lock comprises generally a stationary 
casing and a rotatable rotor mounted therein, the rotor being arranged so 
that it may be rotated to a certain or other angular position by means of 
a mechanical key preferably formed into an elongated blade. For this 
purpose, the rotor is formed at its front surface with a key insertion 
opening. 
With use of such a conventional cylinder lock, it has been experienced that 
rain drops will invade through said key insertion opening into the 
interior space of the rotor. 
In a rather recently improved cylinder lock intended for avoiding such 
defect as referred to above, a pivotable shutter member is provided in the 
interior space of the rotor, said shutter closing normally from inside the 
key insertion opening under the influence of a back-up spring in order to 
shut off the water invasion from outside. 
When the driver introduces the key blade through the insertion opening, the 
shutter is forcibly rotated so as to open and to allow the key further to 
advance into. 
Since the return spring for the shutter is rather weak, part of the rushing 
water as met in the car washing period may frequently invade through the 
key insertion opening into the interior space of the cylinder rotor, 
thereby resulting in rusting and corrosion of small metal parts, such as 
springs and tumblers as met in extended usage of the cylinder lock 
assembly. 
Especially, when the wetted key is introduced into the key cylinder in 
rainy weather, water drops will be entrained into the inside hollow space 
of the key cylinder, thereby similar troubles being invited. 
Especially in cold winter, the entrained water drops may be frozen and 
thus, smooth locking and unlocking operations will be disturbed. 
It is therefore a main object to provide an improved cylinder lock assembly 
in which water invasion as met with use of a wetted mechanical key can be 
effectively prevented. 
It is proposed according to the present invention for attaining the 
foregoing purposes, a cylinder lock assembly comprising a stationary 
casing and a cylinder rotor having a front key-insertion opening, a 
key-guide way kept in communication therewith, a series of key-operated 
tumblers, the front portion of said key guide way having an enlarged front 
inside space for mounting therein a spring urged shutter normally closing 
said key-insertion opening from inside, said assembly being characterized 
by that said rotor is provided with a soft-elastic wiper positioned within 
said rotor for wiping out occasionally entrained water by the key. 
Further, in the inventive cylinder lock assembly, the said wiper comprises 
a frame portion and a pair of resilient flaps having their root portions 
made rigid with said frame, the mating edges of said flaps forming a 
normally closed slit which is, however, openable by receiving a force from 
the key when it is being advanced towards its operational position. 
Further, in the cylinder lock assembly according to the invention, the said 
wiper is provided at a position selected between enlarged space and the 
first one of said tumbler series. 
Still further, in the inventive cylinder lock assembly, said wiper is 
arranged crosswise to the key guide way. The said enlarged space is formed 
with a discharge opening for discharge of the wiped-out water by the 
wiper. The said stationary casing is formed again with a discharge opening 
kept in fluid communication with the said discharge opening at said 
enlarged space for further discharging the wiped-out water towards outside 
of the assembly. 
Further, the said enlarged opening is formed substantially into a 
cone-cylindrical shape. 
Further, the said discharge opening provided at the enlarged space is 
directing downwards. In the similar way, the said discharge opening 
provided through the stationary casing is directing again downwards.

Now referring to the accompanying drawings, character A, FIG. 2, represents 
a cylinder lock which comprises, as its main constituents, a stationary 
casing A' and a rotatable rotor 1 mounted therein. The rotor is fitted 
rigidly on a ring projection 1c, FIGS. 1 and 3, formed at its front end or 
head 1a, FIGS. 1 and 3, with a cover or cap 4, FIGS. 1, 3 and 4, having an 
elongated opening 4a, FIGS. 1, 3 and 4, serving for the key-insertion 
purpose. 
The head 1a, FIGS. 1 and 3, of rotor 1 is formed with an axially extending 
hollow space 1b in the form of substantially a cone-cylindrical shape, as 
seen most clearly in FIGS. 1 and 3. 
Numeral 2, FIGS. 1 and 3, represents a shutter member which is pivotably 
mounted at 3 in the said hollow space 1b, an urging spring S being 
provided for resiliently urging the shutter towards its closing position 
shown in FIG. 3 relative to the key insertion opening 4a. The key is shown 
generally at K in FIG. 4 in its entire perspective view, as having an 
enlarged manipulating grip portion K1 and an elongated and serrated 
working slender portion K2, as is conventional. 
A plurality of traversely and alternatingly zig-zag arranged parallel 
tumblers 5 are slidably provided, as conventionally. This parallel 
arrangement of tumblers 5 are illustrated only in a highly simplified 
manner. However, for the purpose of more clear understanding, one of them 
is shown in FIG. 4, in its full and perspective view, together with its 
outwardly urging spring 9. 
At a small distance from the foremost one of the tumbler series, which is 
denoted specifically with a dashed reference 5', FIGS. 1 and 2, the rotor 
1, FIGS. 1 2 and 3, is formed with a lateral slot 1d which may be of a 
substantially same configuration with that of each of the successive 
parallel traverse slots 1d', 1d" . . . receiving the slidable tumbler 
series 5. This specific lateral slot 1d receives and surrounds opposite 
lateral edges and opposite sides of a wiper 6 having an opening or window 
6c normally closed or substantially closed and allowing frictional and 
wiping pass of the reduced and working portion K2 of key K when the latter 
has been introduced through the entrance window 4a and advanced in and 
along a longitudinal key guide slot 12 extending along the longitudinal 
axis of key cylinder 1 and in registration with the key receiving entrance 
opening 4a. The wiper 6 is made preferably of a soft or resilient material 
such as synthetic rubber, teflon or the like, and comprises a frame-like 
portion 6' and a pair of oppositely arranged, mutually cooperating wiper 
flaps 6a and 6b, the thickened root portions thereof being made integral 
with two opposing chords of said wiper frame 6'. There is a forcibly 
openable slit 6c formed by mutually contacting edges of the wiper flaps 
6a; 6b. 
Cylinder casing A' is formed at its front bottom with a discharge opening 7 
for finally discharging wiped-out aqueous moisture or water from inside to 
outside, as will be later more fully described. In FIG. 2, the discharge 
opening 7 is seen clearly. The casing A' is formed further with axially 
separated front and intermediate ring projections 13 and 14, FIG. 2, so as 
to provide a ring groove 15 formed therebetween, so as to collect part of 
car washing water. The effective part of the discharge opening 7 
penetrates the groove bottom. In addition, a decorating and protecting, 
thin metal cap 16 covers the front end of the casing A', for closing the 
front open end of water-discharge window 7, as shown in FIG. 2. 
Numeral 8, FIGS. 1 and 3, represents a water discharge opening, preferably 
round in its cross-section for ease of fabrication, and formed through the 
bottom wall of cylinder rotor head 1a and within the range of hollow space 
1b, as is clearly seen in FIGS. 1 and 3. This round opening 8 is kept in 
fluid communication with the discharge opening 7 for discharge of wiped 
out water droplets, as will be more fully described hereinbelow. 
Numeral 10 represents a camming member which is mechanically connected with 
a conventional mechanical or electrical door-locking and unlocking 
mechanism, not shown, for opening the door, not shown, when the key K is 
pushed through the key insertion opening 4a and for operating the 
specifically selected number of tumblers 5, 5' towards door-opening 
position and turned to a certain rotated angle of the lock cylinder 1. 
This partial rotational movement of the rotor is transmitted through the 
camming member 10 to the door unlocking and locking mechanism for opening 
the door which mounts fixedly the assembly A at 15, although not shown. 
During this keying operation, the flap 6 is forcibly receded from its 
entrance window-closing position shown in FIG. 3 to its opening one shown 
in FIG. 1 by the pushing action provided by the tip end of operational 
portion K2 of the key. Then, the portion K2 penetrates forcibly through 
the wiping slit 6c of wiper 6, thus aqueous droplets or film if attached 
onto the key surfaces being effectively wiped out and then discharged 
through the openings 8 and 7 from inside to outside of the door lock 
cylinder assembly. 
In this way, a double prevention effect against water invasion can be 
attained.