United States Patent 3788107

This is a three in one lock having a sliding bolt adapted to be engaged in a keeper, and having a keyed tumbler operated detent for locking the bolt against withdrawal from the keeper and for locking the bolt in released position, and having a headed pin which can be used as a chain door guard and which for this purpose is adapted to be inserted in an elongate slot in the bolt and which is secured to one end of a chain that is fastened at its other end to the keeper.

Application Number:
Publication Date:
Filing Date:
Brainerd Manufacturing Co. (Rochester, NY)
Primary Class:
Other Classes:
International Classes:
E05C17/36; (IPC1-7): E05B65/06; E05C17/36
Field of Search:
70/93,129 292
View Patent Images:
US Patent References:
2724257Safety chain door retaining latch1955-11-22Segal
2105714Bolt and chain lock1938-01-18West

Primary Examiner:
Champion, Marvin A.
Assistant Examiner:
Tremblay, Richard P.
Attorney, Agent or Firm:
Shlesinger, Fitzsimmons & Shlesinger
Having thus described my invention, what I claim is

1. A door locking mechanism comprising

2. A door-locking mechanism as claimed in claim 1, wherein said slot in said bolt is approximately the same length as said keyhole slot in said housing, whereby, while said pin is engaged in said slots, said bolt can be slid longitudinally in said housing to and from its locking position.

3. A door-locking mechanism as claimed in claim 1, wherein

The present invention relates to door locks, and more particularly to door locks comprising a slidable bolt and a keeper therefor.

There are many different devices for locking doors. Commonly, however, they fall into three principal classes, namely, the tumbler type lock, the sliding bolt type lock, and the chain door guard. In the tumbler type lock, a key is inserted into a rotatable barrel that is mounted in the door, to rotate the barrel and move a catch into or out of engagement with the keeper, which is mounted on the door jamb. Sliding bolt locks ordinarily consist of a slidable heavy duty bolt that is mounted on the door, and that is movable manually into or out of engagement with a keeper mounted on the door jamb. Chain door guards are used to limit the amount of movement of a door, that is a distance to which it can be opened, so as to permit a householder, for instance, to talk to someone on the outside of the door without opening it so fully that the person on the outside can intrude into the house. Such door guards, also, are used to permit circulation of air from the outside into a room through a partially open door, but without allowing the door to be opened far enough for an intruder to enter therethrough. Usually, the chain is secured at one end to a fixture on the door jamb, and carries a pin or knob at its other end which is inserted in a keeper on the door, to limit opening of the door. When out of use, the pin or knob is inserted into a slot in the fixture on the door jamb.

Sometimes householders will use all three types of locks to prevent unauthorized entry into a home, one type of lock being mounted above the other on the door, with the three cooperating parts mounted one above the other on the door jamb. The use of all three types of locks is, however, expensive, and often unsightly, and sometimes difficult to install, and moreover, requires three different operations on the part of the householder to securely lock a door, and to open it again.

One object of the present invention is to provide a door lock which will be cheaper and simpler to install than the three described previous types of locks, but which can be used to perform the functions of all three, and provide what in effect is a three-in-one door lock, namely, a keyed tumbler lock, a heavy-duty bolt, and a chain door guard.

Other objects of the invention are to provide a lock of the type described which will take up a minimum of space, and provide a piece of hardware which is attractive in design, and which is more effective in protection of a home than the three separate types of locking devices previously employed.

Other objects of the invention will be apparent hereinafter from the specification, and from the recital of the appended claims, particularly when read in conjunction with the accompanying drawings.

In the drawings:

FIG. 1 is a side elevation showing a door lock made in accordance with one embodiment of this invention, and disposed in a position of use;

FIG. 2 is a plan view of this lock with the bolt in released position;

FIG. 3 is a view looking at the left-hand end of FIGS. 1 and 2:

FIG. 4 is a view looking at the right-hand end of FIGS. 1 and 2;

FIG. 5 is a section on the line 5--5 of FIG. 1 looking in the direction of the arrows;

FIG. 6 is a rear view of the bolt and its casing with the closure plate removed, showing the tumbler actuated detent in full lines in position preventing the bolt from being withdrawn from its keeper, and showing in dotted lines the detent in released position;

FIG. 7 is a similar view showing the detent in full lines engaged with the bolt and securing the bolt in released position, and showing in dotted lines the detent in fully released position;

FIG. 8 is a detail sectional view of the tumbler and detent; and

FIG. 9 is a perspective view of the bolt.

Referring now to the drawings by numerals of reference, 10 denotes the housing for the bolt. This is provided with integral flanges 11, and is fastened to the door 12 by screws 14, which pass through holes 13 in the flanges 11 and thread into the door. The housing, which may be of brass, for instance, is formed with a longitudinal recess or groove 15 (FIG. 5) in which a heavy-duty bolt 16 in slidable. The bolt has an elongate longitudinal groove 18 (FIGS. 5 and 9) in its upper surface. This groove is aligned with an elongate keyhole slot 20 in the upper surface of the housing 10. The slot 20 terminates in an enlarged portion 22.

The bolt 16 is provided with spaced ears 28 at one side between which a handle 30 (FIGS. 1 and 5) is secured by a pin 32 (FIG. 5). The handle projects outwardly through a slot 34 in one side of the housing so as to permit sliding the bolt manually in the housing to and from locking position.

The bolt also has a projection or tongue 36 (FIGS. 6, 7 and 9) at one end, which is formed with a kerf 38 in its underside.

Mounted in the housing 10 at a place below and beyond the inner end of the head 22 of the slot 20 to slide at right angles to the direction of movement of the bolt 16 is a detent 40 which has a projection 42 (FIGS. 6, 7 and 8) thereon adapted to engage in the kerf 38 of the bolt in order to lock the bolt in its retracted position shown in FIG. 7. This projection also operates to hold the bolt in its extended, locking position by being moved behind the extended bolt, as shown in FIG. 6. The detent 40 slides between parallel guide surfaces 44 formed in the housing.

The detent is manipulated to and from the positions shown in FIGS. 6 and 7 by a rotary key-operated tumbler 46, which has a pin 48 in its lower end that engages in a cam slot 50 formed in the detent. When the tumbler 46 is rotated, the pin 48 acts like a crank pin to move the detent 40 to and from operative position. The tumbler 46 has a slot 52 (FIG. 1) in it to receive a suitable key 54 (FIG. 8) for manipulating it.

A keeper 60 is secured to the jamb 62 of the door by screws 64, and is recessed to receive the bolt 16 when the bolt is in its extended position, shown in FIGS. 1 and 6. The keeper has a chain 68 riveted or otherwise secured to it at one end, and which carries at its free end a pin 70 which has a first flange 72 on it that is of slightly larger diameter than the width of slot 20 and that is adapted to ride on the outside of the housing. This pin is formed also with a second flange 74 which is small enough to pass through the portion 22 of the slot 20 of the housing and be engaged in the slot 18 of the bolt, when the head 74 is passed through the enlarged portion 22 of slot 20 and slid along the slot, but which is larger in diameter than the main portion of slot 20 so that it cannot be disengaged from the bolt until it is brought into registry with the portion 22 of the slot.

In use, the door lock of the present invention is, in effect, a three-in-one lock. When the door is closed, the bolt can be slid out of the housing, by manipulating handle 30, into the keeper 60 to secure the door locked as would be done with an ordinary heavy-duty bolt. For further protection, the tumbler 46 can be rotated by a key 54, when the bolt is in locking position, to move the detent 40 into position behind the extended bolt, as shown in FIG. 6, absolutely to prevent the bolt from being moved out of locking position. For further security, the locking pin 70 of the chain door guard can be engaged in the bolt by inserting its head 74 through the enlarged portion 22 of the slot 20 and sliding the pin along this slot.

To unlock the door, the tumbler 46 is rotated by the key 54 to move the projection 42 of the detent 40 from behind the bolt; and the bolt can be slid by the handle 30 to the disengaged position shown in FIG. 7. To retain it in this position, the tumbler can be rotated again by the screw 54 to engage the lug or projection 42 of the detent in the slot 38 of the projection 36 of the bolt as shown in FIG. 7.

If it is desired to guard against unwanted intruders, the pin 70 of the chain door guard can be left engaged in the slot 20 of the housing. To open the door freely, the pin 70 needs only to be slid along the slot 20 to the enlarged portion 22 thereof, and lifted out of engagement with the housing. A hole 76 (FIG. 3) is provided in the keeper 60, opposite the side through which the bolt 16 enters the keeper, to receive the head 74 of the pin 70 when the pin is not in use, so that it will not dangle down.

A flat plate 78 (FIGS. 5 and 8) is riveted to the back of housing 10 to hold the parts assembled in the housing. The rivets may be fastened in the holes 79 (FIGS. 6 and 7) in the housing.

While the invention has been described in connection with a specific embodiment thereof, and a particular use therefor, it will be understood that it is capable of further modification and use, and this application is intended to cover any modifications and uses, of the invention that come within the disclosure and the recital of the appended claims.