US 2700887 A
Description (OCR text may contain errors)
O Febl, 1955 o-xHA-NDLER ETAL GLASS DOOR LOCK MOUNTING 2 Sheets-Sheet l Filed June 20, 1951 ruf/A? Arrow/5v5.
Feb. l, 1955 s. oxHANDLl-:R ET Al.
GLASS DOOR LOCK MOUNTING 2 Sheets-Sheet 2 Filed June 20, 1951 v INVENTORS. xse-PN H. Law is HTTOPNE YJ'.
United States .Patent C) GLASS DOOR LOCK MOUNTING Samuel Oxhandler, North Haven, Conn., and Joseph H. Lewis, Kingsport, Tenn.; said Oxhandler assignor to Sargent & Company, New Haven, Conn., a corporation of Connecticut, and said Lewis assignor to Blue Ridge Glass Corporation, Kingsport, Tenn., a corporation of New York Application June 20, 1951, Serial No. 232,532
4 Claims. (Cl. 70-451) This invention relates to glass doors and, in particular, to the mounting of a lock on a door formed of a single sheet of tempered glass.
For a number of years, the use of glass doors has been common and, due to their natural beauty and strength their use is becoming increasingly popular for the most part, such doors have been formed of quite thick, heavy and expensive plates of glass, and they are used princlpally as entrance partitions for large buildings and other places in which their expense is more than offset by their strikingly attractive appearance. Relatively few attempts have been made to provide glass doors which can cornpete economically with the usual wooden, part wooden, or steel doors such as are used to partition off otlice spaces, or other rooms, and one reason for this is that such doors must be made of relatively thin and light glass sheets so as to cut down the cost.
Where such thin sheets are used, great diticulty is experienced in mounting the requisite hardware, such as hinges and locks, so that the strains exerted on the door hinges and lock latches are safely absorbed by the mass ofthe glass. Tempered glass is quite a strong building material, but, as is now well-known, cut-outs on a tempered glass plate made to accommodate hardware-securing means may result in weak spots which, if subjected to excessive strains, fracture and cause the whole p late to shatter into many small, though rounded and usually harmless fragments.
The same is true of the heavier tempered plates, although these plates, being thicker, are proportionately stronger and capable of withstanding strains.
The present invention is concerned solely with mounting door locks on the glass plates. Perhaps the most desirable lock is what is known as a mortise-type lock which includes an aligning cylinder normally insertable into a hole formed in the free, unhinged edge of the glass door, the cylinder extending through a separable shaft that mounts handles on its end portions, and also incorporates the latch actuating and locking mechanism. These locks are desirable because their handles on which the lockactuating means are mounted are located conveniently and also because they firmly secure the door. However, most glass doors do not employ them because any attempt to form the opening for the latch cylinder weakens the glass structure to such an extent that it becomes unt for use. instead, glass door manufacturers have attempted to circumvent this difficulty by designing special locks that grip the top or bottom of the door, although, it will be readily appreciated that such special locks are relatively expensive, inconvenient and ineicient.
In a few instances, mortise-type locks have been mounted on the doors by use of special adapter plates which receive and hold the lock and, in turn, are keyed to the glass. Such an arrangement is desirable and the idea basically valuable, but the adapters that have been developed are not satisfactory due to their unattractiveness, expense, and, also, because they are so secured to the door that strains to which they are subject are transmitted to the weaker, edge portions of the glass cut-outs, instead of being spread out over a large, and assuredly strong area ofk the glass.
As regards this localization of strains on the cut edge portions of the glass, most of the prior adapter plates are secured to the glass by having their edge port1ons bonded by a metal, such as rose metal, to the cut edges of the glass, with the result that there is a metal-glass ice contact and the forces acting on the latch of the lock are transmitted through the metal directly to the weakest portion of the glass. In effect, such a mounting of an adapter plate is, if anything, little more than an improvement upon a mounting in which the metal of the lock actually contacts the glass, and, it has been found, that any such direct contact between the metal and the cut edges of the glass results in breakage. Such direct contact either between metal and glass, or keying material, such as rose metal, and glass would be particularly objectionable in thin glass doors, such as may be used economically as office partitions and the like.
It is therefore an object of this invention to provide an economical manner of mounting and securing a standard lock at a convenient position on the free edge of a glass door; the mounting avoiding any metal-glass contact and being capable of transmitting shocks and other forces acting on the lock to the massive portion of the glass rather than localizing these forces at its cut edge port1ons.
A further object is to provide such a lock for a thin, economical glass door.
A still further object is to provide a manner of so holding a lock adapter to the glass of the door that the recess, or cutout, necessarily formed in the glass to receive the adapter and the lock does not materially weaken the glass structure.
Briey stated, the invention resides in utilizing a pair of plates as an adapter to receive the lock, the plates being formed of a moldable plastic material of high tensile strength. To secure the adapter to the door without employing any metal-glass contact, the plates are positioned on either side of the free edge of the glass door around a recessed portion adapted to receive the lock mechanism, and a clamp, which extends through the plates and the recess, is tightened against the exterior surfaces of the plates to firmly press them into a tight frictional engagement with the glass. Most suitably, the plates are formed with inwardly projecting rib portions adapted to engage the cut-edge of the recess, although this cut-edge is not bonded to these ribs by any metal. With such an arrangement, any jars, shocks, or strains to which the door lock is subjected are transmitted by the plastic to the glass of the door and, further, a substantial portion of these strains are transmitted to the vertical faces, or outside surfaces, of the glass around the recess and from those faces spread to the massive body of the door, rather than being concentrated at the cut-edge portion. With such a mounting, it has been found that the so-called mortise-type locks can safely be secured at a conyenient height to the free, unhinged edge of a relatively thin, monolithic glass door without impairing the tempered strength of the glass. The preferred shape of the adapter and the curvature of the glass door recess will be discussed in subsequent descriptions.
The preferred embodiment of the invention is illustrated in the accompanying drawings of which Fig. l is a front elevation of the adapter mounted on the free edge of a glass door; Fig. 2 an exterior side elevation of one of the pairs of plates forming the adapter, the outline of the glass door being shown beneath it in dotted lines; Figs. 3 and 4 interior side elevations of the plates; Fig. 5 an exploded view of the pair of adapter plates, the plates each being sectioned along lines V-V of Figs. 3 and 4 and being disposed in position to be fitted together around the glass door; Fig. 6 a perspective showing the adapter mounted in the door recess and the lock with its component parts separated and in position to be inserted into the recess and secured to the adapter; Fig. 7 a plan view of the door and lock assemblage; and Fig. 8 a section along line VIil-VIII of Fig. 7.
Referring to the drawings, glass door 1, for which thls lock mounting is particularly suitable, is a single sheet of tempered glass of approximately f/s thickness, although it will be understood that the mounting also could be used for other conventional glass doors of different thicknesses. To enhance the appearance of the door, it, preferably, is formed without any metal framework, and the requisite strength is obtained by tempering or, in other words, by heating the glass sheet to 1100 or 1200 degrees F. and then suddenly cooling it with an air blast, or the equivalent. Glass so treated is capable of withstanding the impacts to which a door normally is subjected, but, if the surface of the sheet is broken, it immediately shatters into many small rounded fragments. For this reason, it is necessary to cut any hardware-receiving openings in the glass before it is tempered, and these openings must be cut in a particular manner so as to insure that their edge portions become tempered. One feature of this invention is that the adapter, generally indicated by numeral 2, used for mounting the lock can be so formed that a recess 3, provided in the free-edge 4 of the door to receive it and the lock, can be cut in a manner that will not result in weakened areas when the glass subsequently is tempered. This will be apparent to persons acquainted with the art of cutting glass to be tempered, but, generally, it may be said that the mounting of the adapter avoids the necessity of drilling any small holes or forming other radii of curvature such as would impair the temper. Also, as will be apparent, the adapter is formed so that it can receive most any standard locking mechanism.
Since the locking mechanism may be of most any standard make, the mechanism, best illustrated in Figs. 6 and 8, is used only for descriptive purposes. Referring to those gures, it is seen that the lock includes an aligning cylinder 6 which mounts a face plate 7 and which, when employed for a conventional wooden or steel door, normally is receivable in a bore drilled in its free, unhinged edge. The mechanism includes a tube 9 which is provided with a transverse opening 13 for receiving aligning cylinder 6, and is provided at its ends with exteriorly threaded portions 22 and 23. These threaded portions are engaged by interiorly threaded ferrules 17 and 18 provided with enlarged head portions 19 and 21 that engage the outer small-diameter ends of clamping plates 14 and 16. Within tube 9 there is a rotatable tubular member 8 that is attached to one of a pair of knobs 12, such member being provided at its inner end with an angular opening as shown which receives an angular head shown at the outer end of a shaft 11 that is attached to the other of knobs 12, the arrangement being such that rotation of either knob will actuate a latching bolt in aligning cylinder 6 in a well known manner. There are a number of other locks similar to that described above, these commonly being known as the mortise-type locks, and, as will be appreciated, the present invention is intended to include such modifications as might be necessary to render adapter 2 suitable for use with these other standard type locks.
Adapter 2 is formed of two plates 26 and 27 (Fig. 1) which are pressed and clamped, by plates 14 and 16 of the locking mechanism, against opposite vertical faces of the glass door. although. if desired. the adapter may be made up as a unit by connecting the two plates together at their outer ends. As previously stated. the lock is mounted at a convenient height on the free, unhinged edge of the glass door and this edge is recessed, or provided with a cut-away portion, to receive the adapter and the locking mechanism. Such a recess 3 is shown in dotted lines in Fig. 2, and it includes a relatively shallow cut into free edge 4 of the door, this cut forming arcuate glass edge portions 28 and 29 against which the plastic adapter presses in a manner to be described. These arcuate edge portions converge one toward the other to a certain point at which the cut, or recess, in the glass door, is leveled olf to form a longitudinal opening 31 that is widened arcuately at its inner end into a transverse circular opening 32. Longitudinal opening 31 of the recess is adapted to receive in a spaced relationship latch aligning cylinder 6 of the locking mechanism, while transverse circular opening 32 is provided to receive tube 9 thereof, such tube also extending through transverse openings 33 (Fig. 2) formed in each of the adapter plates and, to prevent any iniurious contact between metal tube 9 and the glass, opening 33 is considerably smaller than transverse opening 32 of the glass so that tube 9 must lie in spaced relationship from the wall of opening 32.
As noted, the plastic adapter plates are pressed tightly into engagement with the glass and each of the plates is provided with certain anges which frictionally engage the glass to prevent the adapter from sliding laterally out of its recess and also with other members which form an aligning interlock between the two plates. As far as structural elements are concerned, these plates are identical one with the other, although there is a diierence in the arrangement of certain elements that will be explained later.
Referring to Figs. 3, 4 and 5, it may be noted that each adapter plate is provided with inwardly extending ribs 36 and 37 each of which are of such a length that when the plates are pressed against the glass door, the ribs come into a tight frictional engagement with the vertical face of the door, or, to be more specific, these ribs are of such length that, when so pressed, they are indented slightly by roughened surfaces of the glass door and therefore grip the door more irmly in order to assure tight frictional engagement. Rib 37 extends around the peripheral edge of the adapter plate, while rib 36 is circular. Concentrically spaced from rib 36 and formed around opening 33 of the plate, is a shorter circular rib 38 which, primarily, provides a thickened portion beneath the surfaces against which the locking mechanism presses.
Also, projecting inwardly from each plate are arcuate ribs 39 and 41 which are of such a length that, as may be noted in Fig. 5, they lie in tlush engagement with arcuate edges 28 and 29 of recess 3 of the glass door. By the use of such annular ribs as ribs 39 and 41, the forces acting upon the latch of the locking mechanism as the doorA is opened or closed, are transmitted directly to the glass, but, as there is no metal bond between these annular flanges and the glass, the contacted edges of the glass are fully capable of absorbing these forces, the plastic being sufficiently pliable and resilient to dampen the impacts.
As may be noted in Figs. 3 and 4, each plate is provided with other interconnecting ribs 42 extending between circular ribs 36 and 37, as well as ribs 43 extending between arcuate ribs 39, 41 and circular ribs 36, the primary purpose of such interconnections being to render the structure more rigid and increase the frictional holding capacity of the plates.
To interlock the two plates so as to hold their desired alignment and prevent their parting, plate 26 is provided with inwardly projecting ribs 44 and 46, while plate 27 also is provided with ribs 47 and 48, rib 44 being of the same form as rib 48 and rib 46 being identical to rib 47. The plates are so constructed that when plate 26 is uppermost, as in Fig. 5, its long rib 46 overlaps short rib 48 of plate 27, and its short rib 44 is overlapped by long rib 47 on plate 27. The faces of both plates are the same when viewed from their insides, as seen in Figs. 3 and 4. The outer ends of ribs 46 and 47 are provided with recesses 49 and 51, respectively, which receive lugs 53 and 52 on plates 27 and 26, respectively. When plates 26 and 27 are clamped upon the opposite faces of a door with the rib 46 of plate 26 overlapping the rib 48 of plate 27, and the rib 47 of plate 27 overlapping the rib 44 of plate 26, the thus-overlapped ribs are drilled to provide them with screw holes for receiving screws 54 (Figs. 1 and 6) which extend through the previously-mentioned face plate 7 of the locking mechanism. These screws engage the overlapped ribs to secure the locking mechanism to the adapter and to hold the adapter plates together.
The above description has been concerned principally with the structural elements of the adapter plates and the locking mechanism and, of course, it is necessary to mount the locking mechanism on the adapter plates and to, secure it in position, although, as has been stated, the nal'means for so securing the lock are screws 54. The door. locks are mounted on the door by placing the plates in opposite sides of the door, inserting tube 9 of the lock into openings 33 of the adapter plates and then inserting aligning cylinder 6 in through opening 31 of the door recess and through transverse opening 13 of the tube 9 of the lock. Shaft 11, extending from one knob 12 then may be telescopically inserted into the tubular extension 8 of the other knob so that the latch may be manipulated by either knob. With these members so secured, the lock may be fastened to the adapter by means of screws 54, or the like, run through openings provided for them in keeper plate 7 of the aligning cylinder and anchored in the described manner, in engaged ribs 46, 47 and 44, 48. Most desirably, ribs 44 and 47 are indented from the free-edge portion of the adapter plates so that the keeper plate tits snugly into a rectangular groove formed for it.
At this point, it should be noted that the lock and the adapter plates are securely connected together, but also that there is no bonding or keying of the adapter plates to the glass. Instead, as has been intimated, the adapter plates are held to the glass simply by the frictional engagement of their ribs 36 and 37 and this frictional engagement is effected by the clamping pressure of the locking mechanism. To obtain this pressure, threaded ferrules 17 and 18 are rotated so as to press tightly against clamping plates 14 and 16 of the locking mechanism, these clamping plates exerting their pressure against the outer faces of the adapter plates adjacent to circular ribs 38. As a consequence, the clamping pressure forces ribs 36 and 37 of the adapter plate into intimate frictional engagement with the glass and prevents the adater plates from sliding laterally out of the recess formed in the glass. To assure a tight t of these ribs the adapter plates are formed of a plastic having the properties of the butyrate acetate resins, or, in other words, a plastic which is both easily moldable and cast and which has a high tensile strength and a relatively high coefficient ot friction on glass, one example of snch a resin being known as Tenite. However, if desired, a suitable and attractive rubber or rubber-like material may be substituted for the plastic, one such rubber-like material being Silastic which is a brand of polysiloxane rubber. The frictional engagement of the ribs has been found to be sufficient to hold the adapter in place, but if desired, some non-hardening cementitious material may be used to insure the engagement.
There are a number of advantages inherent in the lock mounting described above. Most important7 perhaps, of these advantages is the fact that no metal contacts the glass at any point, so that there is no danger of breakage due to shocks being transmitted to the glass through an nnyieldable material, such as metal. Instead, the strains to which the lock is subjected are transmitted primarily through the shock-dampening plastic adapter to the outside, uncut, surfaces of the glass door. There are, of course, forces acting directly on the latch when the door is closed and these are transmitted through arcuate ribs 39 and 41 to arcuate edges 28 and 29 of the glass, although a certain amount of such forces are absorbed by the plastic and the glass further is protected since ribs 39 and 41 bear directly against the arcuate edges of the glass and prevent any relative movement of the adapter with respect to the glass. As a result, all normal shocks and impacts are safely absorbed and breakage should not take lace. p Another improvement of this invention is that the adapter is quite simple and inexpensive to manufacture and to secure in place. Further, since the mounting requires no special keying or bonding by means of an opaque substance, the outward appearance of the adapter is not marred. If desired, the adapter plates may be formed of a clear, transparent, plastic material, so that the crystalline effect of the monolithic tempered glass door is not spoiled by the lock mounting.
According to the provisions of the patent statutes, we have explained the principle, preferred embodiment and mode of operation of our invention, and have illustrated and described what is now considered to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.
1. An adapter for holding a lock to the free edge of a glass door that is provided with a recess for receiving the adapter' and lock, said adapter comprising a pair of plates each having its interior surface formed of a formable synthetic material having a relatively high coefficient of friction on glass and each provided with a transverse opening, and a clamp extending through said plates for pressing said plates against the faces of the door around said openings frictionally to form the sole attachment of the adapter and lock to the door, each of said plates being provided with an inwardly projecting rib adapted to fit snugly against the edge portions of said recess.
2. An adapter for holding a lock to the free edge of a glass door that is provided with a recess for receiving the adater and lock, said adapter comprising a pair of plates each formed of a formable material having a relatively high coefficient of friction on glass and each provided with a transverse opening, and a clamp extending through said plates and said recess for pressing said plates against the faces of the door around said openings frictionally to form the sole attachment of the adapter and lock to the door and firmly holding the adapter to the door, each of said plates being provided with inwardly extending ribs adapted in length to engage said door faces and also with another inwardly projecting rib adapted to fit snugly against edge portions of said recess.
3. An adapter for holding a lock to the free edge of a glass door that is provided with a recess for receiving the adapter and lock, said adapter comprising a pair of plates each formed of a formable material having a relatively high coecient of friction on glass and each provided with a transverse opening, a clamp extending through said plates for pressing said plates against the faces of the door around said openings and rmly holding the adapter to the door, and inwardly-extending ribs formed in said plates overlapping each other, and means for connecting the overlapping portions of said ribs to each other.
4. An adapter for holding a lock to the free edge of a glass door that is provided with a recess for receiving the adapter and lock, said adapter comprising a pair of plates each having its interior surface formed of a formable synthetic resin and each plate being provided with plates for pressing said plates against the faces of the a transverse opening, a clamp extending through said plates for pressing said plates against the faces of the door around said openings and rmly holding the adapter to the door, each of said plates being provided with a pair of inwardly extending ribs, the pair of ribs on one plate being adapted and disposed to engage in a face-toface relationship with the pair of ribs on the other plate, and means securing said engaged pair of ribs together t0 prevent lateral separation of said pair of plates.
References Cited in the file of this patent UNITED STATES PATENTS 640,217 Moore Jan. 2, 1900 868,211 Mullikin Oct. 15, 1907 1,025,938 Young May 7, 1912 1,720,640 Wread July 9, 1929 1,942,525 Weller Jan. 9, 1934 2,200,387 Erath May 14, 1940 2,263,772 Gold et al Nov. 25, 1941 2,533,582 Hillgren Dec. 12, 1950 2,568,273 Clark Sept. 18, 1951 FOREIGN PATENTS 467,745 Great Britain June 23, 1937