US3309125A - Automatic door lock - Google Patents

Description

Mweh M, 3967 H. NEVELING AUTOMATIC DOOR LUCK 2 Sheets-Sheet 1 Filed Sept. 22, 1964 lNVE/VTOF IL/ 1? W/G N5 VEL m/c g/u WM 2 Sheets-Sheet 2 Filed Sept. 22, 1964 0 J a 01 u.

HEZfn/IG A/E VEL ING United States Patent 3,309,125 AUTOMATIC DOOR LOCK Herwig Neveiing, 148 Honnetalstrasse, Deilinghofen, Westphalia, Germany Filed Sept. 22, 1964, Ser. No. 398,314 1 Claim. (Cl. 292-78) This invention relates to an automatic door lock in which the latch is operated by a rectilinearly guided energy storage means, which is coupled with a damping piston, through the intermediary of a gear with beyonddead center position.

In the known door locks of this kind, the lever-type latch is coupled with a spring serving as an energy storage means, through the intermediary of a lever system. In the unlocking position of the latch, the spring is compressed. Since, however, the transmission rods are in a beyond-dead center position, the spring is not capable of pivoting the latch into its locking position. When the door is being closed, the latch strikes against the locking plate, where-by the beyond-dead-center position is overcome so that the spring can move the latch into its locking position with the door being pulled into the doorframe. The locking is clamped by the action of a damping piston.

In a known automatic door lock of this type, the latch is secured to an angle lever which is coupled with the energy storage means through the intermediary of a con necting rod. In this arrangement, the arm of the angle lever which is hinged to the connecting rod must have a length sufllcient to securely reach the beyond-dead center position. Moreover, a sufficient length of this lever arm is also required to ensure that the door is pulled shut as smoothly as possible. Consequently, the installation of such a door lock in relatively thin door edges is very ditficult. The numerous bearings of the rod guide involve considerable wear. Finally, the accurate installation of this door lock requires an exceptionally high skill, since even the slightest tilting Will be sufficient to cause the latch to strike the locking plate in a one-sided manner, which will result in deformations of the lever system and damage of the door lock.

Another known door lock, which, however, lacks an energy storage means, has a complicated lever system including an arm-rocker lever and a plurality of guide rods so that this door lock is still more subject to the above-mentioned difficulties.

Also, a door lock for heavy doors such as stove-doors is known in which a fork-like latch bears with a cam against a spring-biased plate. When the door is being closed or pulled open, the latch is shifted and moved into the respective end position by the spring-biased plate. This lock has no damping means so that it works rather roughly. Consequently, it is not suited for normal doors in which the closing movement is to be damped by the door lock.

It is the object of the present invention to avoid the disadvantages of the known door locks and to provide a simply constructed automatic door lock in which hinge connections or moving joints are possibly eliminated.

To attain this object, the invention provides an automatic door lock in which the latch is operated by a rectilinearly guided energy storage means, which is coupled with a damping piston, through the intermediary of a gear with beyond-dead center position, which is characterized in that the rod of the energy storage means mounts a rectilinearly guided sliding member of a cam drive, the cam means of the cam drive, which is guided within the sliding member, and the latch being rigidly'mounted on a common pivot.

Preferably, the cam means is an eccentric disc positively seated within the sliding member.

The door lock proposed by the present invention therefore uses only one bearing for the pivot mounting the latch and the eccentric disc. Moreover, only straight or rectilinear slide guides are used so that the lock can be realized with very small dimensions. This feature enables the door lock proposed by the invention to be incorporated in all kinds of doors such as wooden doors or steel doors as well as doors with or without a rebate. If the latch is ununiformly loaded due to improper installation of the lock, the resulting forces can be absorbed by the bearing of the pivot without any transmission of torsional forces to other components of the door lock.

A preferred embodiment of the invention will now be described by way of example and with reference to the accompanying drawings, in which:

FIG. 1 is a side elevational view of an automatic door lock according to the invention;

FIG. 2 is a longitudinal section through the lock viewed in the direction of the attachment plate, with the latch in its unlocking position;

FIG. 3 is a similar sectional view showing the latch in its locking position;

FIG. 4 is a fractional front elevation of the attachment plate with the latch, and

FIG. 5 is an elevational view of a locking plate.

Referring to FIGS. 1 and 2, the automatic door lock proposed by the present invention is secured in a known manner to an attachment plate 1 and accommodated within a lock case 2 which has a mounting plate 3 supporting a damping cylinder 4. The cylinder 4 is retained in its position by fitting edges 7.

The damping cylinder 4 is filled with oil and also accommodates an axially movable piston 5 and a spring 6 which serves as an energy storage means. The spring 6 helically surrounds a piston rod 8 which is integral with the piston 5. The free end of the piston rod 8, which projects out of the damping cylinder, mounts a frameshaped sliding member 9 movable in a straight guide.

The lock case 2 supports a pivot 10 passing through guide slots 11 in the side walls of the sliding member 9 thereby to ensure rectilinear movement of this latter. Within the frame-shaped sliding member 9, an eccentric disc 12 is rigidly mounted on the pivot 10. An abutment plate 13 is inserted in the sliding member 9 and preferably covered by a thin resilient contact member 14, which arrangement is to reduce the friction within the sliding member.

The pivot also carries a latch 15, the shape of which is shown particularly in FIG. 4. Preferably, the latch 15 is mounted on a polygonal extension 16 of the pivot 10. Pivot 10, eccentric disc 12 and latch 15 thus can be rotated in common only.

The piston 5 is sealed off against the bore of the damping cylinder 4 by means of a piston ring 17 and a piston packing 18. A plug 19 closing the open end of the cylinder 4 and having a central passage for the piston rod 8 is sealed by a plurality of packing inserts 20. Internally, the piston 5 is provided with channels 21 having throttling openings.

FIG. 5 shows the shape of a locking plate 23 to be secured to the jamb linings of a door by means of screws.

FIGS. 2 and 4 show the latch 15 in its unlocking position. In this position, the sliding member 9 is lifted together with the piston 5 by the action of the eccentric disc 12. The eccentric disc 12 has been pivoted into a position beyond its dead center, which is conditioned by a fiat edge portion 24 of the periphery of the eccentric disc 12, so that the latch 15 is arrested in its unlocking position.

When the door is being closed, the latch 15 will strike against a nose 25 of the locking plate 26, whereby the eccentric disc 12 is turned back from its beyond-dead center position so that the sliding member 9, under the action of the spring 6, can pivot the eccentric disc 12 and thus the latch 15 into the locking position of the latter, which is designated by reference numberal 15 in FIGS. 3 and 4. Simultaneously, the closing movement of the door is damped by the action of the piston 5.

The latch 15 and the locking plate 23, which, of course, may have any desired shape, are preferably made of wear-resistant plastic or bronze. The same also applies to the eccentric disc 12.

It is self-evident that instead of using the pivot 1% as a guide pin within the slots 11, any other guide, for example of rail shape, can also be used.

To reduce wear, the eccentric disc 12 used is preferably positively coacting with the sliding member 9, which will be the case with a circular disc or an arched triangw lar disc provided with a flattened portion on the periphery such as the flat edge portion 24, to obtain a beyonddcad center position.

Instead of the cam drive comprising the sliding member 9 and the eccentric disc 12, as described with refer ence to the illustrated embodiment, also difierent cam drives can be used, as a matter of course. For example, the sliding member 9 may have any other shape and instead of the eccentric disc 12 a cam may be used.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claim rather than by the foregoing description and all changes which come within the meaning and range of equivalency of the claim are therefore intended to be embraced therein.

I claim:

An automatic door lock comprising means defining a chamber, a piston mounted for rectilinear reciprocal movement in said chamber means, a piston rod coupled to said piston and having an end portion projecting outwardly of said chamber means, an eccentric, means coupling the eccentric to the piston rod end portion, said eccentric being mounted for movement between overcenter and non-overcentcr positions whereby said piston rod is moved in at least one direction, said coupling means including a member carried by said piston rod end portion, said member having a portion in underlying relationship to said eccentric, pivot means coupled to said eccentric and mounting said eccentric for swinging movement about a fixed axis, a latch carried by said pivot means whereby movement imparted to said latch in a iirst direction causes said eccentric to move to the overcenter position thereof while movement imparted to said latch in a second opposite direction causes said eccentric to move to the undercenter position thereof, means for reducing the frictional contact between said member and said eccentric, and said reducing means being defined by resilient means underlying said eccentric.

References Cited by the Examiner UNITED STATES PATENTS 1,120,544 12/ 1914 R'osentreter 1655 2,588,010 3/1952 Kennon 16-55 2,851,296 9/1958 Guyaz 292-78 2,946,613 7/ 1960 Roethel 16-2 FOREIGN PATENTS 1,130,325 5/ 19 62 Germany.

337,998 11/ 1930 Great Britain.

745,271 2/1956 Great Britain.

304,335 3/ 1955 Switzerland.

' EDWARD c. ALLEN, Primary Examiner.

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