Patent Application
20100072762
The present invention is directed to an improved lockset of the type commonly used for latching and opening a door. More specifically, the invention is provides a lockset having knobs which can be securely grasped and turned by one who is infirm in order to release a door latch but on which a noose cannot be securely tied.
Psychiatric patients have been known to attempt suicide by hanging while in hospitals or other psychiatric institutions. Hanging is sometimes accomplished by passing a noose formed from a bed sheet, dressing gown, shoe lace, dental floss, or other readily available elongated flexible object available to the patient, to a fixture from which the patient may be hanged.
Although rooms at psychiatric institutions are, to the extent possible, kept free of fixtures to which a noose can be attached, virtually every room has a door and door handle for opening and closing the door. Moreover, furniture in such rooms sometimes is equipped with handles. Such door knobs or handles are commonly of a configuration which permits a noose to be secured to them with sufficient stability to support the weight of a patient and, thereby, enable asphyxiation of the patient by hanging.
Psychiatric patients who may be inclined to commit hanging are often elderly and/or arthritic, and have difficulty grasping a door or drawer knob. The goals of providing a door knob or drawer knob configured to prevent attachment of a noose and that of making the door knob or drawer knob easily graspable by the patient who may have limited physical capacity to turn a knob are at odds with each other.
The present invention provides a lockset with one or more door knobs configured to prevent attachment of a noose while enabling secure gripping for ease of unlatching a door.
It is therefore an object to provide a lockset with one or more knobs to which a noose cannot be securely tied.
Another object of the invention is to provide such a lockset with knobs which can be easily gripped and rotated to unlatch a door by a person having limited physical capacity.
A further purpose of the invention is to provide a lockset which can be fitted into a standard door lockset opening while employing exposed knobs to which a noose cannot be securely affixed.
Still a further objective of the invention is to provide a lockset having knobs which are easily gripped but present no surfaces or edges which can cause injury to a person gripping them.
Other and further objects of the invention will be apparent from the following drawings and description of a preferred embodiment of the invention in which like reference numerals are used to identify like parts in the various view.
Referring now to
Referring now to
Referring to
A knob bushing 19 has a body with circular disc 23 and a central aperture. Extending from each from each side of the disc 23 is a hollow cylindrical boss 20 centered on the disc of the bushing 19. A knob bushing 19 is mounted on each of the knobs 9, 11 by three mounting screws 21.
An end of the cylindrical boss 20 is received in the intermediate portion 12 of the bore while the disc 23 is received in the enlarged portion 10 of the bore. An actuator which is rotatable for causing the latch retractor 7 to unlatch the door is provided in the form of a spindle 25 extending from each knob 9, 11. Each spindle 25 has a driving length with a square cross section and an axially displaced connecting length with a threaded cylindrical portion that is screwed into the end of the cylindrical boss 20 protruding from each of the knob bushings 19 opposite the end received in the intermediate bore portion 12 of the knob 9, 11. When screwed fully into the boss 20 of each knob bushing 19, the spindle extends into the narrower portion 14 of the central bore in each knob 9, 11.
Mounted on respective outer surfaces of the door 3 are the outside rose 13 and an inside rose 14. Two posts 33 with threaded cylindrical bores secure the latch retractor 7 which is sandwiched between the outside rose 13 and inside rose 14. Screws 35, passed through apertures in the inside rose 14 and through the door 3 are received in the hollow threaded cylindrical posts 33 which are affixed to the outside rose 13.
Rotatably mounted within a central cylindrical bore in each of the outside rose 13 and inside rose 14 is a needle roller bearing 39 through which a respective spindle 25 of one of the knobs 9, 11 is passed. Each needle roller bearing is held in place by a washer 41 and retaining ring 43.
Referring additionally to
Concavities 43 are equally spaced about a circumference of the tapered conical surface of each knob 9, 11. The concavities 43 preferably have rounded edges. In the preferred embodiment of the invention there are six such concavities. However, the number of concavities can be increased or decreased within the scope of the invention. The circumference of each knob 9, 11 is free of any projections or grooves on or in which a noose could snag when pulled in a direction parallel to or away from the door 3.
The concavities 43 are generally shaped with parallel sides and rounded ends and are sized to accommodate the finger pads of a person in order to enable the knobs to be turned without slipping through the fingers. There are no projections or other raised surfaces on the circumference of each knob 9, 11 to which a noose can be secured.
In accordance with the preferred embodiment of the invention, each of the knobs 9, 11 has at its end distal from its respective rose 13, 14, an integral handle 16 having a rectangular face 18 with ends 20 that meet the tapered surface of the conical knob 9, 11, and trapezoidal recesses 22 on opposite sides of the rectangular handle 16.
The handle 16 may be grasped between the fingers as an alternate way of gripping the knob 9, 11 for rotation in order to unlatch the lockset. A lip 24 surrounds each recesses 22 on three sides. The ends of each lip 24 meet a shoulder 26 having a planar surface orthogonal to the axis of rotation of the knobs 9, 11. Each shoulder 26 serves as a stop for a finger when the handle 16 is grasped for rotating each knob 9, 11. The recesses 22, lips 24, and shoulder 26 allow for a secure grasp of each knob 9, 11, without slippage, for persons who are infirm or otherwise unable to tightly grip the knob 9, 11.
Referring now to
Elimination of the rectangular handle enables the knob 9′ to be axially shorter than the knobs 9, 11 with all other dimensions being equal. This can be advantageous for persons with small hands who do not require the use of a handle. The hands can be placed over the front of the knob 9′ with the fingers inserted into the concavities 43 for grasping and rotating the knob 9′.
The knob 9′ is less costly to fabricate than the knobs 9, 11, easier to clean due to fewer recessed surfaces, and may be considered more aesthetically pleasing to the eye.
The knob 9′ may be substituted for either or both of the knobs 9, 11, in accordance with the invention.
It is to be appreciated that the foregoing is a description of a preferred embodiment of the invention to which modifications and variations may be made without departing from the spirit and scope of the invention.
