US2793895A - Safety lockset - Google Patents

Description

May 28, 1957 F. PLoDARl 2,793,895

SAFETY LOCKSET Filed April 19, 1955 2 Sheets-Sheet l May 28, 1957 F. PLoDARl 2,793,895

SAFETY LOCKSET Filed April 19, 1955 2 Sheets-Sheet 2 United States Patent It is a purpose of the present invention to provide a safety lockset which can be locked so as to prevent entry from outside, said lockset being operated by extremely simple and effective mechanical means. The hitherto known devices for locking doors and the like may be divided into a first classs including all the elementaryv means which do not depend upon the lockset proper and are, instead, separate therefrom; for instance padlocks, bolts, and chains tted at one end with Ia shaped expansion intended to be introduced into a slot and removable therefrom; and a second class including all the bolts, united to the lockset proper, which can be actuaated by the same key used Yfor actuating said lockset.

Among the defects of the mechanisms of the rst class are the inadequate security achieved thereby and the necessity 4of drilling additional holes in the door frame in order to install the lockset, and to these defects one must also add the impairment of the appearance of the doors resulting from the installation of such auxiliary safety locks.

The most conspicuous defect of the mechanisms of the second class is that a key can actuate them both from outside and from inside, so that it is possible, despite the various developments and improvements hitherto adopted, that ill-disposed people may break the lockset with picklocks or similar tools and enter the dwelling abusively.

The mechanism embodying the present invention makes it possible to prevent entrance into the dwelling by operating from the inside thereof a push-button located in the door knob of the lockset and unlocking can be effected from inside only, by once again acting on said pushbutton. In other words, after the lockset has been locked from the inside of the dwelling, it is not possible to open thedoor from the outside, even by using the'key intended to enter the keyway located in the `outer door-knob of the lockset.

A practical embodiment of the invention, its operational features and the component parts thereof will be readily understood from the following description and accompanying drawings, wherein:

Fig. 1 is an exploded elevational view, partly broken away and in section, of a lockset in which a safety mechanism embodying this invention has been incorporated;

Fig. 2 is a fragmentary sectional view taken along the line II-II of Fig. 1; and

Fig. 3 is an end elevational view of the assembly of Fig. 2.

Referring to the drawings in detail, and initially to Fig. l thereof, it will be seen that, in a lockset embodying the present invention, the inner door knob is formed of two axially separable hollow portions 1 and Z. The safety lock mechanism embodying the present invention is accommodated within the inner door knob and includes a push button 3 of stepped, cylindrical configuration which is closed at its end of smaller diameter. The small diameter portion of the push button 3 pro- *Patented May 28, 1957 jects axially out of a central opening in the knob part mfice i 1, while the radial shoulderdened between the large and small diameter portions of the push button 3 forms a seat for one end of a helical return spring 4.

A generally axially extending toothed lever 5 is disposed within the push button 3 and is rockably mounted,

at one end, in an aperture of a partition 3a within the small diameter portion of the push button.

Mounted within the part 2 of the inner knob is a generally rectangular frame 2a opening axially in the direction toward the part 1 of the inner knob.` A ratchet wheel 6 is mounted within the frame 2a for rotation about an axis extending perpendicularlyvrelative to the axis of rotation `of the inner door knob and is adapted to be engaged by the toothed lever 5 when the parts 1 and 2 of the door knob are fitted axially together. One end of the axle of the ratchet wheel 6 is extended from the frame 2a, as at 6a, and carries a cam member 7 for rotation with the ratchet wheel. The cam 7 is preferably of rectangular configuration, with rounded corners, and is engageable with a plate 8 fixed on one end of a pin 10 which is disposed parallel to, and radially spaced from, the axis of rotation of the door knob, and is mounted, in a support bracket 9, for longitudinal move- Y spindle 15, on which the inner door knob and an outer door knob 17 are secured, inner and outer roses 14 and 18, respectively, adapted to be secured to the opposite faces of the door, and a latch bolt 19 operated, in the usual manner, in response to rotation of the spindle 15 by one or the other of the door knobs. In the illustrated embodiment of the invention, the central portion 12 of the inner rose 14 is provided with an opening 16 (Fig. 2) which is disposed the same radial distance from the axis of rotation of the spindle 15 as is the pin 10, and the closed end of the knob part Z is formed with an opening 2b which is aligned with the pin 10 to receive the end of the latter remote from the plate 8. The opening 16 of the inner rose 14 is angularly disposed, in relation to the rotation of the spindle 15, so that the opening 16 will register with the opening 2b when the latch bolt 19 is in its operative position, that'is, inits extended position engaging the keeper plate (not shown) to prevent opening of the associated door.

The pin 10 is movable axially between a locked position (Fig. 2) wherein the end of the pin projects through the opening 2b and into the opening 16 -of the inner rose 14 thereby to prevent rotation of the spindle 15 and unlocking of the door, and a released position in which the end of the pin 10 is withdrawn from the opening 16 to permit the usual rotation of the spindle 15 by the inner or outer door knob. The rectangular cam 7 is formed so that the difference between its larger and smaller dimensions will be equal to the length of stroke of the pin 10 necessary to move the latter between the above described locked and released positions.

As seen in Fig. 1, the teeth of the lever 5 and of the ratchet wheel 6 are raked so that the ratchet wheel will be rotated in the counter clockwise direction, as viewed in Fig. 1, when the lever 5 is moved toward the left, and so that, `during the return movement of the lever 5, toward the right, the teeth of the lever 5 will merely slide over the teeth of the ratchet wheel 6 so as to avoid counter rotation of the ratchet wheel during such return movement.

The above described lockset having a safety lock mechanism embodying the present invention operates as follows:

Assuming that the safety lock mechanism is initially in its released condition, that is, with the ratchet wheel 6 disposed so that the long edge surface of the cam 7 engages the plate 8 on the pin 10 to permit the spring 13 to move the latter to its released position where the end of the pin is withdrawn from the opening 16 of inner rose 14, depression of the push button 3 into the inner knob will cause the lever to move axially within the knob, and by reason of its engagement with the ratchet wheel 6, the toothed lever will produce rotation of the ratchet wheel through an angular extent of 90 degrees. Such angular displacement of the ratchet wheel will bring the short side of the rectangular cam 7 into engagement with the plate 8, thereby to stroke the pin to its operative or locked position where the end of the pin extends into the opening 16 of the inner rose 14. With the pin 10 in its locked position, it will be apparent that rotation of the spindle by actuation of the outer door knob 17 will be positively prevented. When the push button 3 is freed, the spring 4 will return the latter to its original position projecting from the inner door knob and, during such return movement, the toothed lever 5 will merely slide over the periphery of the ratchet Wheel 6 and the latter will remain in its rotational position corresponding to the locked condition of the safety lock mechanism.

When it is desired to release the safety lock mechanism, such release can only be effected from inside. The desired release is obtained by merely again depressing the push button 3 so that the engagement of the toothed lever 5 with the ratchet wheel 6 will cause angular displacement of the rectangular cam 7 through 90 degrees, and such angular displacement of the cam will once again bring a long side of the latter into engagement with the plate 8 so that the pin 10 will then be free to be returned to its released position by the spring 13. Upon the withdrawal of the end of pin 10 from the opening 16 of the inner rose 14, the spindle 1S will be free to be rotated by actuation of either the inner or outer door knob.

Although an illustrative embodiment of the present invention has been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to that precise embodiment, and that various changes and modication may be effected therein without departing from the scope or spirit of the invention, except as defined in the accompanying claims.

What I claim is:

1. In a lockset having inner and outer roses for mounting `on the opposite faces of a door and inner and outer knobs secured to a common rotatable spindle intended to operate a latch bolt; the combination of a locking pin, means mounting said pin within the inner knob parallel to, and spaced radially from, the Iaxis `of the spindle and permitting longitudinal movement of said pin between a released position Within said inner knob and a locked position projecting axially from the latter, said inner rose having an opening therein spaced radially from said axis of the spindle a distance equal to the radial spacing of said pin from said axis and disposed to register with said pin and receive the latter in a predetermined rotated position of said knobs and spindle, a push button slidable axially in said inner knob and having a portion adapted to project from the latter, a return spring urging said push button in the direction for projecting said portion of the latter from said inner knob, a generally axially extending toothed lever rockably mounted on said push button for movement with the latter, a ratchet wheel mounted within said inner knob for rotation about an axis perpendicular to the axis of the spindle and being engageable by said toothed lever, a cam fixed to said ratchet wheel for rotation with the latter, follower means on said pin engageable by said cam, and resilient means acting on said pin to urge the latter toward said released position and to engage said follower means with said cam, said cam being formed so that, in at least one rotational position thereof, said cam moves said pin to the locked position of the latter, and, in at least one other rotational position of the cam, said pin is free to be returned to its released position by said resilient means, said toothed lever and ratchet wheel being formed so that the latter is angularly displaced between positions corresponding to said released and locked positions of said pin during each depression of said projecting portion of the push button into said inner knob.

2. In a lockset; the combination of claim l, wherein said cam is of rectangular configuration and said follower means includes a flat plate on 'an end of said pin engageable alternatively with the long and short sides of said rectangular cam, said toothed lever being operative to elect rotation of said ratchet wheel and cam through 9() degrees during each depression `of said projecting portio-n of the push button.

References Cited in the tile of this patent UNITED STATES PATENTS 2,361,734 Baume Oct. 3,1, 1944 2,580,196 Schlage Dec. 25, 1951 2,644,704 Hagstrom July 7, 1953

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