US3408836A

US3408836A - Safety door lock

Info

Publication number: US3408836A
Application number: US498747A
Authority: US
Inventors: Jr Earl M Trammell
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-10-20
Filing date: 1965-10-20
Publication date: 1968-11-05
Anticipated expiration: 1985-11-05

Description

NOV- 5, 1968 E. M. TRAMMELL, JR 3,408,836

SAFETY DOOR LOCK Filed Oct. 20, 1965 EARL. M. TRAMMELL. JR

ATTORNEY.

nited State ABSTRACT OF THE DISCLOSURE The latch-conditioning device includes a reciprocating plunger, which extends through a housing mounted on a door, and which connects to the plunger rod of an automobile door lock. The plunger includes a flat lock abutment. A lock member is reciprocatively mounted within the housing in a direction perpendicular to the path of the plunger to engage the at abutment and lock the plunger. The lock member extends out of the housing, when in the plunger-unlocked position, for digital locking operation. The unlocking operation is performed by inserting a thin instrument, such as a key, through an elongate slot in the housing to cooperate with a shouldered recess in the lock member. The lock member may thus be moved outward of the housing to a plungerunlocked position.

This invention relates generally to improvements in a safety door lock, and more particularly to improvements in a device for selectively conditioning the latch mechanism of an automobile door.

The subject of this invention constitutes improvements over the subjects of other patents issued to this applicant, namely, U.S. Patent No. 2,708,845, U.S. Patent No. 2,735,288, U.S. Patent No. 2,735,289, U.S. Patent No. 2,939,307, U.S. Patent No. 2,939,308, U.S. Patent No. 2,955,858, U.S. Patent No. 3,096,114 and U.S. Patent No. 3,206,956.

This safety door lock is particularly useful on the doors of automobiles, and serves selectively to prevent a latch-conditioning element located on the inside of such a door from being manually moved to a doorunlatched position, and hence prevents the door from opening while the vehicle is in motion. Thus, it becomes impossible for children occupying the automobile to open the door, and the hazard of a child falling from a moving Vehicle is eliminated.

It is a major objective of the present invention to provide a protective arrangement for a door-latch plunger utilized on an automobile door, the device selectively preventing the unintended, casual or otherwise unwanted actuation of the latch mechanism from door-latched position to door unlatched position.

Other important advantages are realized in that the guarding device permits the usual operation of the doorlatch plunger, yet can be utilized when the specific need arises to avoid the hazards discussed above.

An important object is achieved by the provision of a lock housing through which the plunger extends in its reciprocative movement between a door-unlatched position and a door-latched position, and by the provision of a lock member reciprocatively mounted in the lock housing for movement between a plunger-unlocked position and a plunger-locked position, the lock member selectively engaging a lock abutment on the plunger when the lock member is moved to the plunger-locked position, whereby to hold the plunger in the door-latched position. The size of the lock member is predetermined so as to extend out of the lock housing when in the plungerunlocked position whereby the lock member can be selectively moved digitally to the plunger-locked position, and is predetermined so as to be shielded in the lock 3,408,836 Patented N ov. 5, 1968 l Hice housing when in the plunger-locked position whereby the lock member cannot be digitally moved to the plungerunlocked position.

Another important objective is realized by the structural arrangement in which a shoulder on the lock member is aligned with an aperture in the lock housing when the lock member is shielded by the housing in the plunger-locked position, the aperture being of a size to preclude digital access therethrough, yet enable insertion of a thin instrument to engage the shoulder a and move the lock memberto the plunger-unlocked position in which the lock member is disengaged from the lock abutment and the plunger is released for the usual latchconditioning operation.

Still another important objective is afforded by the provision of a spring means in the lock housing engaging the lock member and tending to retain the lock member selectively in either the plunger-locked or plungerunlocked position. This construction requires that a delinite digital pressure be applied to the lock member to move it from the extended plunger-unlocked position to the retracted and shielded plunger-locked position. Similarly, a delinite outward force must be applied to the lock member shoulder by a thin instrument inserted through the housing aperture to release the plunger by moving the lock member from its retracted plungerlocked position to the extended plunger-unlocked position.

An important object is attained by the provision of a positive locking connection between the plunger and the lock member, this connection including a flat on one side of the plunger forming the lock abutment, and including a linger on the lock member selectively extending across the plunger flat and engaging the lock abutment when the plunger is moved to its door-latched position and the lock member is moved to its plunger-locked position.

Another important object is provided by the mounting of the plunger at one end of an elongate lock housing, the lock housing embracing the periphery of the plunger and extending laterally from one side, and by reciprocatively mounting the lock member in the other end of the lock housing. Specifically, the elongate lock housing includes top and bottom walls through which the plunger extends, and includes an open end through which the lock member extends outwardly of the lock housing for digital access when disposed in the plunger-unlocked position.

Yet another important objective is achieved by the unique means of attaching of the plunger to a latchconditioning rod, the attachment being made through a small hole in the lock housing aligned with the fastening means carried by the plunger for securing the plunger to the rod when the plunger and rod are disposed in the door-unlatched position. It is advantageous to locate the fastening means on the same side of the plunger shank below the flat formed in the shank which provides the lock abutment.

An important objective is to provide a safety door lock that is simple and durable in construction, economical to manufacture and assemble, highly efcient in operation, and which can be easily installed and operated by anyone with only a minimum of instruction.

The foregoing and numerous other objects and advantages of the invention will more clearly appear from the following detailed description of a preferred embodiment, particularly when considered in connection with the accompanying drawing, in which:

FIG. 1 is a front elevational view of the safety door lock assembled on the left-hand rear door of an automobile, the plunger being lowered to the door-latched position;

FIG. 2 is a side elevational view of the safety door lock illustrating the plunger lowered to the door-latched position and the lock member retracted to the plungerlocked position;

FIG. 3 is a cross-sectional view taken along line 3 3 of FIG. 12;

FIG. 4 is a cross-sectional view taken along line 4 4 of FIG. 3;

FIG. 5 is a cross-sectional view taken along line 5 5 of FIG. 4;

FIG. 6 is a side elevational view of the safety door lock similar to FIG. 2, but illustrating the plunger raised to the door-unlatched position and the lock member extended to the plunger-unlocked position;

FIG. 7 is a cross-sectional view taken along line 7 7 of FIG. 6, the actuating instrument such as an ignition key being shown in broken lines; and

FIG. 8 is a longitudinal cross-sectional` view of the plunger and associated rod.

Referring now by characters of reference to the drawing, and iirst to FIG. 1, it will be noted that the safety door lock is mounted on the left-hand rear door of an automobile. Of course, this safety door lock can be advantageously utilized on the right-hand rear door with equal facility, as will be explained in detail subsequently.

The automobile door 10 is of conventional construction including a window sill frame 11 through which the glass pane 12 slidably extends. The mechanism for conditioning the door latch (not shown) includes a plunger rod 13 extending upwardly through a hole 14 formed in the window sill frame 11.

Attached to the upper end of rod 13 is a plunger generally indicated by 15 which is iitted also within the window frame hole 14. The construction of the plunger 15 is perhaps best shown in FIG. 8. For example, the plunger 15 includes an elongate shank 16 provided with an integral, relatively enlarged head 17 that can be easily gripped for manual, reciprocative movement. The plunger shank 16 is provided with a bottom-opening, elongate bore 20 extending substantially to the plunger head 17. The plunger rod 13 is received in the bore 20. It will be noted that the bore 20 is tapered on one side to accommodate plunger rods 13 of different diameters, and also to facilitate insertion of the rod 13 into such bore 20.

The plunger shank 16 is provided with a special crosssectional contiguration, which is best shown in FIG. 7. The shank 16 includes opposite,

arcuate side walls

21 and 22, and opposite liat

parallel side walls

23 and 24. To provide a compact structure, the side walls 22-24 are relatively thin. The arcuate side wall 21 is relatively thicker for reasons which will later appear.

Formed in the arcuate side wall 21, closely adjacent the lower end of the plunger head 17 is a flat 25 extending perpendicular to the liat side wall 24. The shank flat 25 forms at its lower end, an upwardly facing lock abutment 26.

A small set screw 27 is carried by the thicker arcuate side Wall 21 below the lock abutment 26, the set screw 27 acting to tix the plunger 15 in position on the rod 13.

As is usual, the plunger 15 can be raised to the doorunlatched position illustrated in FIG. 6, or depressed to the door-latched position illustrated in FIGS. 1 and 2.

An elongate lock housing generally indicated by 30. together with its internal component parts, constitutes means associated with the plunger 15 to preclude selectively movement of the plunger 15 from the door-latched position.

The lock housing 30 includes an upper housing portion 31 having a top wall 32, and includes depending and

opposed side walls

33 and 34 integrally interconnected by a depending and rounded end wall 35. The opposite end 36 of housing portion 31 is open. The lower extremity of the depending side and end walls 33-35 is provided with an internal peripheral groove 37.

The lock housing 30 includes a lower housing portion 40 having a tiat bottom wall 41 connected to the upper 4 housing portion 31. Specically, the bottom wall 41 includes a peripheral lateral flange 42 that interiits the internal groove 37, the bottom wall 41 being slid into place from the open housing end 36. The lower housing portion 40 includes an integral and depending tubular collar 43 dening a non-circular opening 44 formed in the bottom wall 41 closely adjacent the closed housing end 35. The opening 44 conforms closely to the non-circular crosssectional configuration of the plunger shank 16. Moreover, the collar opening 44 is aligned vertically below a coacting non-circular opening 45 formed in the top wall 32 of the upper housing portion 31, the housing opening 45 also conforming closely to the non-circular crosssectional configuration of the plunger shank 16. When the plunger is inserted into and through the lock housing 30, and particularly inserted through the vertically aligned

housing opening

44 and 45, the interengagernent of the

flat shank sides

23 and 24 with the peripheries defining the

housing openings

44 and 45 preclude any relative rotation of the plunger 15 and lock housing 30.

Extending laterally outward from one side of the tubular collar 43 is a hook 46 adapted to interfit under the window sill frame 11 when the tubular collar 43 is inserted down through the frame hole 14 to secure the housing 30 to the door 10. For reasons which will later appear, the hook 46 is provided with a desirable weakened area at its juncture with the tubular collar 43 by an arcuate groove 47. This groove 47 constitutes a connection in the device, and particularly a connection in the lock housing 30 that secures the lock housing 30 to the door 10, and which under some circumstances precludes movement of the plunger 15 from its door-latched position. Upon applying at least a predetermined force to the connection through a part of the device such as the plunger 15 or lock housing 30, or both, the connection provided by groove 47 is released by breaking of the hook 46 from the tubular collar 43, thereby allowing the plunger 15 to be raised from the door-latched position when it would otherwise be precluded.

The upper and

lower housing portions

30 and 40 respectively provide an internal guideway leading from the side of the plunger shank 16 to the open housing end 36. When the plunger 15 is associated with the lock housing 30, the lock housing 30 embraces and extends laterally outward from one side of the plunger shank 16. Slidably mounted in the guideway of lock housing 30 is a lock member 50. The lock member 50 is selectively extended to the plunger-unlocked position illustrated in FIG. 7, or retracted to the plunger-locked position illustrated in FIG. 3.

The lock member 50 includes a flat inner end 51 engaging the iiat side 24 of the plunger shank 16 to determine the retracted position of the lock member 50 as is best seen in FIG. 3. Formed integrally with and extending beyond the liat end 51 is a finger 52 constituting an abutment, that extends across the iiat 25 and engages the lock abutment 26 to hold the plunger 15 in its doorlatched position. The finger 52 interlits the space between the liat 25 and the adjacent side wall 34 of the upper housing portion 31.

Formed in the upper side of the bottom wall 41 adjacent the open end 36 of housing 30, and extending transversely the entire width is a narrow groove 53 that is deeper at the center than at the opposite ends. Disposed in the groove 53 is a short length of spring wire 54 that is adapted to extend slightly into the guideway below the lock member 50. A rib 55 depending from the bottom of lock member 50 rides over and engages the spring wire 54 upon movement of the lock member 50 between its limits. As the rib 55 engages the spring wire 54, it depresses the wire 54 downwardly into the groove 53. After the rib 55 passes over the spring wire 54, the wire 54 snaps back up into its original position to engage the side of the rib 55 and tends to hold the lock member 50 in either the plunger-locked position or plunger-unlocked position.

The size of the lock member 50 is predetermined so that in its plunger-unlocked position in which the nger 52 is completely disengaged from the cooperating lock abutment 26, the outer end of the lock member 50 extends outwardly through the open housing end 36 a sufficient distance so that it can be digitally engaged and moved back to the retracted, plunger-locked position. Furthermore, the size of the lock member 50 is predetermined so that when it is in its plunger-locked position in which the at end 51 engages the flat shank wall 24 and the finger 52 engages the lock abutment 26, the lock member 50 is shielded by the housing 30 so that it cannot be gripped digitally for movement away from the plunger-locked position.

The side of lock member 50 is provided with a recess 56 partially defined by an inwardly facing shoulder 57. As is best seen in FIG. 3, the recess 56 including the shoulder 57 is located completely within the lock housing 30 when the lock member 50 is disposed in the plungerlocked position.

Aligned with the recess 56 is an elongate aperture 60 formed in the side housing wall 34, the aperture 60 extending through the open housing end 36. The aperture 60 is small enough to prevent digital access therethrough to the lock member 50. However, the aperture 60 is of sufficient width and length to permit the insertion of a thin instrument such as an ignition key 61 into the recess 56 and into engagement with the shoulder 57 to move the lock member 50 from the plunger-locked position of FIG. 3 to the plunger-unlocked position of FIG. 7.

The upper housing portion 31 is provided with a small oval-shaped hole 62 in the side wall 34 which is aligned with the set screw 27 when the rod 13 is located in its raised position and the plunger is disposed over the rod 13. A suitable tool such as a small hex-wrench (not shown) can be inserted through the hole 62 for engagement with the set screw 27 to tighten or loosen the screw 27 incident to attaching or detaching respectively the plunger 15 and rod 13. It is important that the hole 62 be located in the housing in this location and that it be used in cooperation with the set screw 27 when the plunger 15 and coacting rod 13 are raised, as shown in FIG. 6, because the set screw 27 will never be visible during plunger operation. For example, when the plunger 15 is depressed to the door-latched position shown in FIG. 1, the set screw 27 is moved downwardly to a position below the window sill frame 11. Thus, the set screw 27 is accessible and visible only through the housing hole 62.

A beveled spacer 63 (FIG. 1) constructed of a molded plastic material, is utilized to seat the lock housing 30 on the window sill frame 11 and to hold the plunger 15 vertical. The spacer 63 includes a depending, arcuate post 64 interfitting the frame hole 14. A rubber gasket 65 is disposed about the arcuate post and is clamped between the spacer 63 and the window sill frame 11.

An integral retaining pin 66 depends from the underside of bottom wall 41 of the lock housing 39 and interfits a compatible hole 67 formed in the upper body of spacer 63 to interconnect the spacer 63 and lock housing 30 positively.

It is thought that the functional advantages of the safety door lock have become fully apparent from the foregoing detailed description of parts, but for co-mpleteness of disclosure, the installation and operation will* be briefly described. It will be assumed that the safety door lock is installed on the left-hand door behind the drivers seat.

First, the plunger rod 13 is lifted to its raised position, the rod 13 extending through the frame hole 14 and above the window still frame 11. The lock housing 30 is assembled to the spacer 63, the retaining pin 66 interfitting the spacer hole 67. Then, the lock housing 30 and spacer 63 are placed in position by inserting the arcuate spacer post 64, together with the tubular collar 43 and hook 46, downwardly into the frame hole 14 with the resilient gasket 65 disposed against the window frame 11. The hook 46 is disposed under the Window sill frame 11 adjacent the frame hole 14. This hooking action compresses the resilient gasket 65 between the lock housing 30 and the window frame 11 and clamps the spacer 63 securely in place on the window frame 11. When installed correctly on the door 10, the housing aperture 60 will be facing inwardly toward the interior of the automobile `so that the actuating instrument 61 can be readily inserted from the front seat. In this position, the lock member 50 is located toward the front of the automobile so that it can be readily manipulated from the front seat.

It will be understood that during the installation of the plunger 15, the lock member 50 is located in the extended, plunger-unlocked position to avoid interference of the plunger shank 16 with the locking finger 52. The lock member 50 is moved to the plunger-unlocked position by inserting the thin instrument 61 through the housing aperture 60 into engagement with the shoulder 57. Upon translatory movement of the instrument 61 along the housing aperture 60, the lock member 50 can be extended.

The plunger 15 is then assembled by inserting the plunger shank 16 downwardly into and through the lock housing 30, the plunger shank 16 being inserted through the

housing openings

45 and 44 as the plunger rod 13 enters the plunger bore 20. When installing the plunger 15, the arcuate shank wall 21 carrying the set screw 27 faces inwardly toward the interior orf the automobile. The plunger 15 is adjusted as to height on the rod 13 until the set screw 27 is aligned with the housing hole 62. Then, a hex-wrench is inserted through the housing hole y62 into operative engagement with the set screw 27, the screw 27 being turned to clamp the plunger 15 to the rod 13.

The safety door lock can be installed on the right-hand rear automobile door in exactly the same manner. However, in this installation, the lock member 50 will be facing toward the rear of the automobile, yet the housing aperture 60 will be facing inwardly toward the interior of the automobile, thereby providing an assembly that can be readily manipulated lfrom the Afront se-at.

Under normal usage of the latch-conditioning plunger 15, the plunger 15 can be depressed or raised selectively to latch or unlatch the door 10 from the inside. I-f it is desired to utilize the safety features afforded by the present safety door lock, the plunger 15 is depressed from the door-unlatched position of FIG. 6 to the depressed door-latched position of FIGS. 1 and 2. The lock member 50 is digitally engaged `and retracted in the lock housing 30. `In moving to this retracted position, the rib- 55 rides over the spring wire 54, and the spring wire 54 snaps back to its initial position to hold the lock member 50 in this retracted plunger-locked position. The flat end 51 of the lock member 50 engages the flat shank side 24 to determine the limit of movement. Simultaneously, the finger 52 extends across the plunger shank flat 25 and engages the lock abutment 26, the finger 52 being substantially wedged in the space between the plunger shank flat 25 and the side housing wall 34. The interenga-gement olf the finger 52 and lock Iabutment 26 prevents the plunger 15 from being moved out of the door-latched position. In the retracted, plunger-locked position of the lock member 50, a child cannot grip the lock member 50 to move the lock member 50 out of the plunger-locked position. The door is now safely locked.

When it is desired to open the door, the plunger 15 is released by an adult inserting a thin instrument 61, such as an ignition key, through the housing aperture 60 and into the recess 56. By exerting a translatory force by the instrument 61 against the shoulder 57, and by moving the instrument 61 outwardly along the housing aperture 60, the lock member 50 is moved yfrom the plunger-locked position of FIG. 3 to the extended plunger-unlocked position of FIG. 7. As explained previously, the spring wire 54, during this translatory sliding movement of lock member 50, engages the rib 55, and then snaps back and tends to hold the lock member 50 in this extended position. The iinger 52 is withdrawn from the space between the plunger shank flat 25 and side housing wall 34 and disengaged from the lock abutment 26. The plunger 15 is now released so that it can be lifted from the depressed door-latched position of FIGS. l and 2 to the raised door-unlatched position of FIG. 6. The plunger is now reconditioned for normal usage.

It will be understood that the lock member 5t)r cannot be depressed into the housing 30 except when the plunger l is lowered into the door-latched position.. lIn any other position of the plunger 15, the finger 52 engages the plunger shank 16. The nger 52 is aligned with the plunger shank flat and aligned over the lock abutment 26 only in the depressed door-latched position of plunger 15.

Under some conditions olf emergency, there is no time for inserting a thin instrument 61 through the housing aperture 60 in order to engage and move the lock member 50 from the plunger-locked position to the plungerunlocked position. Under these emergency circumstances, it is desirable to release the plunger 15 quickly and condition the door lock so that the plunger 15 can be immediately raised to the door-unlatched position.

This feature is attained by the provision of a connection in the means associated with the plunger 15 to preclude selectively movement of the plunger 15 from the door-latched position, which is releasable upon applying at least a predetermined minimum rforce to the connection, whereby the plunger 15 can be moved to the doorunlatched position. In the embodiment illustrated, the connection is represented by arcuate groove 47 that provides a weakened area between the hook 46 and tubular collar 43. By exerting at least a predetermined minimum lifting force to either the plunger -15 or lock housing 30, the pressure between the hook 46 and the overlying sill frame 11 will cause the hook 46 to break from the collar 43 along groove 47. Upon continued exertion of upward force to the plunger 15 and/or lock housing 30, the plunger 15 and its associated rod 13 will be lifted to the door-unlatched position.

Of course, it -will be readily understood that this releasable connection can be provided between any of the coacting parts of the safety door lock, as for example between the lock member 50 and plunger 15, between the upper housing portion 31 and lower housing portion 40, and between the plunger 15 and upper housing portion 31, among others.

Although the invention has been described by making detailed reiference to a preferred embodiment, such detail is to be understood in an instructive, r-ather than in any restrictive sense, many variants being possible within the scope of the claims hereunto appended.

I claim as my invention:

1. In ya device for conditioning the latch mechanism of a door:

(a) a reciprocating plunger operatively connected to the latch mechanism and mounted for movement between a door-unlatched position and a door-latched position,

(b) a housing through which the plunger extends,

(c) the plunger including a lock abutment disposed in the housing when the plunger is in the door-latched position,

(d) a unitary lock member reciprocatively Iand slidably mounted in the housing for movement between a plunger-unlocked position and a plunger-locked position, the lock member selectively enga-ging the lock abutment on the plunger 'when the lock member is moved to the plunger-locked position to hold the plunger in the door-latched position,

(e) the size olf the lock member being predetermined so as to extend out of the housing when in the plunger-unlocked position Yfor digital access whereby the lock member can be selectively moved digitally to the plunger-locked position, and being predetermined so as to be shielded in the housing when in the plunger-locked position to preclude digital movement of the lock member to the plunger-unlocked position,

(t) the lock member including a shoulder disposed in the housing when the lock member is in the plungerlocked position, and

(g) the housing being provided with an elongate aperture of a size to preclude digital access therethrough, yet enable insertion of a thin instrument to engage the shoulder of the unitary lock member and move the loc'k member longitudinally of the aperture to the plunger-unlocked position in which the lock member disengages from the lock abutment and releases the plunger.

2. A device as defined in claim 1, in which:

(h) the reciprocating plunger is provided with a at on one side forming the lock abutment, and

(i) the unitary lock member includes a linger selectively extending across the liiat and engaging the lock abutment on the plunger within the housing when the lock member is moved to the plunger-locked position to hold the plunger in the door-latched position.

3. A device as delined in claim 1, in which:

(h) the housing includes an open end receiving the lock member and an oppositely disposed closed end,

(i) the lock member is provided with a recess in one side, the recess being partially defined by the shoulder, and

(j) the housing aperture is elongate and aligned with the recess and communicates with the open end of the housing, the aperture being of a length to permit insertion of the thin instrument into the recess so as to engage the shoulder effectively :for selective movement of t-he lock member to the plunger-unlocked position.

4. In a device for conditioning the latch mechanism of a door:

(a) a plunger operatively connected to the latch mechanism and mounted for movement between a doorunlatched position and a door-latched position,

(b) a housing through which the plunger extends,

(d) a lock member reciprocatively mounted in the housing for movement between a plunger-unlocked position and a plunger-locked position, the lock member selectively engaging the lock abutment on the plunger when the lock member is moved to the plunger-locked position to hold the plunger in the door-latched position,

(e) the size of the lock member being predetermined so as to extend out of the housing when in the plunger-unlocked position for digital access whereby the lock member can be selectively moved digitally to the plunger-locked position, and being predetermined so as to be shielded in the housing when in the plunger-locked position to preclude digital movement of the lock member to the plunger-unlocked position,

(f) the lock member including a shoulder disposed in the housing when the lock member is in the plungerlocked position,

(g) the housing bein-g provided with an aperture of a size to preclude digital access therethrough, yet enable insertion of a thin instrument to engage the shoulder and move the lock member to the plungerunlocked position in which the lock member disen- Igages from the lock abutment and releases the plunger,

(h) the housing including top and bottom walls interconnected by side walls, one end of the housing being closed, the opposite end being open, and

(i) the lock member extending outwardly of the housing through the open end when disposed in the plunger-unlocked position.

5. A device as defined in claim 4, in which:

(j) the aperture is elongate and is provided in one side wall of the housing, the aperture extending through the open end of the housing.

6. In a device for conditioning the latch mechanism of a door:

(b) a housing through which the plunger extends,

(d) a lock member reciprocatively mounted in the housing for movement between a plunger-unlocked position nad a plunger-locked position, the lock member selectively engaging the lock abutment on the plunger when the lock member is moved to the plunger-locked position to hold the plunger in the door-latched position,

(g) the housing being provided with an aperture of a size to preclude digital access therethrough, yet enable insertion of a thin instrument to engage the shoulder and move the lock member to the plungerunlocked position in which the lock member disengages from the lock abutment and releases the plunger,

(h) the housing being elongate and extending laterally from the plunger,

(i) the plunger being reciprocatively mounted in one end of the housing for movement therethrough,

(j) the housing including a guideway in the housing leading from the side of the plunger to an opening in one end of the housing, and

(k) the lock member being reciprocatively mounted in the guideway for movement toward or away from the plunger, the lock member extending outwardly of the end opening in the housing when in the plunger-unlocked position for selective digital movement of the lock member to the plunger-locked position.

7. In a device for conditioning the latch mechanism of a door:

(b) a housing through which the plunger extends,

(h) the housing extends about and encompasses the plunger,

(i) the plunger extends outwardly of the housing for digital movement to either the door-latched or doorunlatched position,

(j) the housing includes an end opening, communicating with the elongate aperture, and

(k) the lock member is provided with a recess partially delined by the shoulder, and the lock member is reciprocatively mounted in the housing in a path -transverse to the path of the plunger, the shoulder being disposed outwardly of the housing beyond the end opening when the lock member is disposed in the plunger-unlocked position for selective digital actuation inwardly of the housing to the plungerlocked position.

8. In a device for conditioning the latch mechanism of a door:

(b) a housing through which the plunger extends,

(h) the housing including top and bottom walls, each provided with a non-circular hole,

(i) the plunger having a non-circular shank extending through the compatible non-circular holes to preclude lrelative turning of the plunger and housing', yet enable reciprocative movement of the plunger through the housing,

(j) the plunger having a at side adjacent the lock member,

(k) the lock abutment extending substantialy perpendicular to the ilat side,

(l) the lock member including a flat inner end engaging the flat side of the plunger to determine the plunger-locked position, and

(m) the lock member including a inger projecting beyond the flat end and engaging the lock abutment in the plunger-locked position to hold the: plunger in the door-latched position.

9. In a device for conditioning the latch mechanism of a door;

(b) a housing through which the plunger extends,

(g) the housing being provided with an aperture of a i size to preclude digital access therethrough, yet enable insertion of a thin instrument to engage the shoulder and move the lock member to the plungerunlocked position in which the lock member disengages from the lock abutment and releases the plunger,

(h) the housing being elongate, encompassing the periphery of the plunger, and extending laterally from one side of the plunger,

(i) the housing including top and bottom walls, and opposite side walls, one end of the housing being closed, the opposite end being open,

(j) the housing providing a guideway extending from the end opening to the side of the plunger within the housing,

(k) the lock member being reciprocatively mounted in the housing and disposed in the guideway, the lock member being movable in a path transverse to the path of movement of the plunger,

(l) the lock member extending outwardly of the housing through the end opening when disposed in the plunger-unlocked position,

(m) the aperture being elongate and provided in one side wall, the aperture extending through the end opening of the housing, and

(n) the plunger extending through the top and bottom walls of the housing.

10. In a device for conditioning the latch mechanism of a door:

(b) a housing through which the plunger extends,

(c) the plunger including a lock abutment disposed in Cil 12 the housing when the plunger is in the door-latched position,

(e) the size of the lock member being predetermined so as to extend out of the housing when in the plungerunlocked position for digital access whereby the lock member can be selectively moved digitally to the plunger-locked position, and being predetermined so as to be shielded in the housing when in the plungerlocked position to preclude digital movement of the lock member to the plunger-unlocked position,

(h) the housing including top and bottom walls provided with aligned non-circular holes,

(i) the plunger having a non-circular shank extending through the compatible holes to preclude relative turning of the plunger and housing, yet enable reciprocative movement of the plunger,

(j) the plunger having a fiat side adjacent the lock member, and having a fiat on an adjacent side forming the lock abutment extending substantially perpendicular to the said at side,

(k) the lock member including a fiat inner end engaging the flat side of the plunger to determine the plunger-locked position,

(l) the lock member including a nger projecting beyond the at end and selectively extending across the fiat of the plunger and engaging the lock abutment on the plunger when disposed in the plungerlocked position to hold the plunger in the doorlatched position,

(m) the lock member being provided with a recess in one side partially defined by the shoulder, and

(n) the aperture being elongate and aligned with the recess, the aperture being of a length to permit insertion of the thin instrument into the recess so as to engage the shoulder effectively for selective movement of the lock member from the plunger-locked position.

11. In a device for conditioning the latch mechanism of ya door;

(b) a housing through which the plunger extends,

(h) the housing including top and bottom walls, and opposite side Walls, one end of the housing being closed, the opposite end being open,

(i) the plunger extending through the top and bottom Walls of the housing adjacent the closed end,

(j) the housing embracing the periphery of the plunger and extending laterally from one side,

(k) the housing providing a guideway extending from -the open end to the side of the plunger within the housing,

(l) the plunger being provided with a bottom-opening bore adapted to receive a rod,

(m) fastening means being carried by the plunger for for attaching the plunger to the rod,

(n) the housing being provided with a small hole aligned with the fastening means when the plunger and rod are disposed in the door-unlatched position for access to the fastening means to attach or detach the plunger and rod,

(o) the plunger having a fiat side adjacent the lock member and having a flat on an adjacent side forming the lock abutment extending substantially perpendicular to the said flat side,

(p) the lock member bein-g reciprocatively mounted in the housing and disposed in the guideway for movement toward or away from the plunger in a path transverse to the path of the plunger movement,

(q) the lock member including a at inner end engaging the flat side of the plunger to determine the plunger-locked position,

(r) the lock member including a finger projecting beyond the flat end, extending across the plunger flat and enga-ging the lock abutment in the plunger-locked position of the lock member to hold the plunger in the door-latched position,

(s) the lock member extending outwardly of the housing through the end opening when disposed in the plunger-unlocked position,

(t) the lock member being provided with a recess in one side partially defined by the shoulder,

(u) the aperture being elongate and provided in one side Wall of the housing, lthe aperture extending through the open end of the housing, and

(v) spring means located in the housing and engaging the lock member, the spring means tending to retain the lock member selectively in either the plungerlocked or plunger-unlocked position.

12. In a device as dened in claim 1, in which:

(h) a frangible connection is provided which is releasable upon applying at least a predetermined force -to the connection, the connection including a predetermined zone of weakness, so that the plunger can be moved to the door-unlatched position under a condition when the plunger is precluded from such movement by the lock member.

References Cited UNITED STATES PATENTS 1,158,720 11/1915 Rohr 292-287 2,581,606 1/1952 Seaman 29274 2,629,246 2/ 1953 Schumann 70-181 2,735,289 2/ 1956 Trammell 70--181 2,788,235 4/ 1957 Gilmour 292--347 2,874,988 2/1959 Sage 292-347 3,096,114 7/1'963 Trammell 292-347 3,206,956 9/ 1965 Trammell 70-181 MARVIN A. CHAMPION, Primary Examiner.

E. I. McCARTHY, Assistant Examiner.