US2864642A - Door knob construction - Google Patents

Description

f Dec. 16,1958 R. MURPHY I 2,864,642

DOOR KNOB CONSTRUCTION Filed July 18, 1956 M 30 L, l m

IN VE N TOR CHAAL as A? MURPHY 19 T TORNEHS DOOR KNOB CONSTRUCTION Charles R. Murphy, Grosse Pointe Park, Mich.

Application July 18, 1956, Serial No. 598,557 1 Claim. (Cl. 292-353 The present invention relates generally to latch operating mechanisms and more particularly to a door latch operating assembly for use on doors of buildings and the like.

7 In conventional door latch constructions, a knob is normally adjustably secured to each end of a spindle and fitted to the door by means of adjustment of the knobs axially on the spindle. In one common door knob construction, the knob is threaded onto the spindle and a set screw is provided at the reduced inner end of the knob which may be tightened against a portion of the United States Patent spindle to prevent subsequent axial and rotary move ment of the knob relative to the spindle. However, the set screw frequently loosens, often to the extent of making the latch inoperative by movement of the knob, since rotary movement of the knob in one direction tightens thesame against the door whereas a reverse rotation of the knob merely removes the same from the spindle.

Prior attempts to provide a more secure and a more positive connection between the knob and the operating spindle have resulted in complex, expensive devices which are difficult to assemble and disassemble and which freguently had portions of the securing mechanism clearly exposed on the exterior of the knob assembly.

In comparison to these prior latch operating mechanism constructions, such, for example, as disclosed in U; 8. Patents Nos. 1,734,520, Hazelwood, November 5, 1929 and 1,887,655, Marple, November 15, 1932, the operating assembly of the present invention provides an extremely inexpensive and simple constructionwherein the meansfor-afiixing the knob to the operating shaft is completely concealed within the shank of the knob and is so constructed that it does not require an extremely long shank as does the Hazelwood construction. In addition, the stem engaging detent means of the present invention provides a positive engagement between the knob .and the shaft whereby the spring detent means is rigidly supported and does not take the full force by itself but immediately transmits such force to surrounding structures. Thus, the spring detent means is not subject to excessive fatigue as is the detent means of Hazelwood.

Accordingly, it is one object of the present invention to provide a door latch operating assembly having an improved means for attaching knobs, handles, levers or the like to operating spindles of latch mechanisms.

Another object is to provide a device of the above type which may be easily and readily assembled on and disassembled from the operating spindle and yet which has the securing mechanism entirely enclosed within the knob to improve the appearance of the device and to prevent undesired tampering and disassembly of the same.

Another object of the present invention is to provide such a knob, handle or the like wherein the detent means engaging between the knob and the operating spindle is so arranged that the forces transmitted through such detent means are readily transmitted to the surrounding ICC structure so that the detent means will not be subject to excessive wear and fatigue.

Another object of the present invention is to provide an improved latch operating mechanism of attractive and modern appearance which is so adapted to mass production that its cost will be low enough to permit of its substitution for presently installed latch operating mecha- Other objects of this invention will appear in the fol lowing description and appended claim, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

In the drawings:

Fig. l is a side elevation of a latch operating mechanism embodying the present invention with one knob thereof shown in cross section.

Fig. 2 is a sectional view taken on the line 22 of Fig. 1 in the direction of the arrow showing the means of aflixing the adjustable knob to the latch operating spindle.

Fig. 3 is a fragmentary sectional view taken on .the line 33 of Fig. 2 in the direction of the arrows.

Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

. Referring to Fig. 1 of the drawings, the latch operating mechanism of the present invention comprises the operating spindle 10 having the two knobs 12 and 14 aflixed to either end thereof.

As shown in Fig. 1, the operating spindle 10 is provided with the teeth 16 on both ends thereof. These teeth are inclined toward the center of the spindle for a purpose to be described hereinafter.

As can be seen in Fig. 1, the knobs 12 and 14 are of a two-piece construction. I have found it advantageous to mold the knobs of a thermosetting plastic resin. The knob 12 is shown in cross section in Fig. 1 and is illustrative -also of the basic construction of the knob 14. As there shown, the knob 12 is molded in two pieces 18 and 20. The portion 18 is provided with an axially extending shank 22 to engage the operating spindle 10. I have found it advantageous to mold the portion 18 of knob 12 around the end of spindle 10. A portion of the material of the shank 22 will flow into the spaces between the teeth 16 thereby assuring that the portion 18 of the knob 12 is rigidly affixed to the end of the operating spindle. The outer portion or cap 20 of the knob 12 is molded of similar material and as can be seen in Fig. 1 is provided with a flange portion 24 that extends over a portion of the outer end of the body portion 18 of the knob. This detail of construction provides for simple and rapid assembly of the two knob portions. A small amount of cement is placed on the inside of the flange 24 and the cap 21) is then pressed over the end of the body portion 18 of the knob. Thus, any excess cement will be forced inside of the assembled knob and will not run onto the outside of the knob. This saves considerably since this method of assembling the knob obviates any necessity for cleaning off any excess cement. This is especially important when the knob is molded of the thermosetting resins since the cement ordinarily used with such resins would mar the smooth outer surface of the knob.

The knob 14 is constructed of two pieces as is the knob 12. However, as can be seen in Figs. 1 and 2,

3 the knob 14 is not molded integrally with the spindle 10. Instead, the axial opening 26 is provided to receive the end of the operating spindle 10. This axial opening extends" entirely through the shank portion of. knob 14 and corresponds to the cross-sectional configuration of spindle 10.

Referring now to Fig. 2 of .the drawings, the means of affixing the knob 14 to the end of the operating spindle 10 so that the knob 14 will be adjustable axially on the spindle can be explained in detail.

The shank of the knob 14 is provided with a slot 28 which is transverse and communicates with the axial opening 26. At one end this slot is provided with a cutaway portion 28a for a purpose to be explained hereinafter. A V-shap'ed spring member 30 is positioned within the slot 28 with the lower arm 30a thereof engaging in one of the teeth 16 on the operating spindle 10. The other arm 30b is provided with the downturned end 30c thereon. A metal band 32 is afiixed around the shank portion of the knob 14 and covering the slot 28. The end 30c of the spring 30 engages the inner portion of this metal band 32. Thus, the resiliency of the spring 30 urges the lower arm 30a into engagement in the teeth 16 of the operating spindle. As can be seen in Fig. 1, the teeth 16 are directed inwardly toward the center of the spindle. Thus, the adjustable knob 14 can be assembled on the end of the spindle 10 by merely forcing the same thereon. The direction of the teeth 16 acts to allow the arm 30a of spring 30 to slip over the teeth as the knob is being forced inwardly on the spindle. However, the angle of the teeth assures that the spring arm 30a engages therewith in such a manner that the knob cannot be pulled out unless the arm 30a is disengaged from the teeth 16. In order to facilitate this disengagement, an opening 34 is provided in the band 32 to allow the insertion of a pointed instrument to engage the end of spring arm 30a to lift the same out of engagement with the teeth 16 thus allowing the knob to be removed from the spindle when desired. Also, it can be seen that providing the cutaway portion 28a of the slot 28 leaves the end of spring arm 30a readily accessable.

Referring now to Fig. 3 of the drawings the method of affixing the band 32 on the shank of the knob 14 can be explained in detail. The knob 14 is provided with an outwardly tapered seat portion 36 thereon. It will be noted that this outwardly tapered portion 36 overlies the slot 28. The band 32 is continuous and may be cut from a length of tubing. The inner diameter of the band is slightly larger than the outside diameter of the end of the shank portion of the knob. Thus, the band can be freely passed over the end of the shank of the knob 14 until the band engages the tapered seat portion 36. The band is then forced onto the tapered seat portion and is passed into permanent position thereon. This method of affixing the band assures that it can be assembled on the shank without scratching or marring the shank.

Having thus described my invention I claim:

In a latch operating mechanism including a spindle extending from the latch mechanism and adapted to operate the same by rotary movement, a series of teeth provided on said spindle adjacent at least one end thereof, an operating knob mounted on the toothed end of said spindle by means of an axial opening mating with said spindle and selectively movable longitudinally thereon, the improvement consisting of; a reduced. portion on said knob through which said axial opening extends and including a tapered portion joining said reduced portion to said knob and diverging outwardly from said reduced portion, a transverse slot in said reduced portion communicating with said axial opening in said knob and transverse thereof, a band positioned on said reduced portion and enclosing said slot, the inner diameter of said band being slightly larger than the outer diameter of said reduced portion and one edge thereof being seated on said tapered portion, a V-shaped spring detent member having the end of the upper arm thereof engaging the inner surface of said band and the lower arm thereof positioned in said slot and engaging between the walls thereof and the said teeth provided on said spindle, and an opening in said band adjacent the end of said lower arm of said spring detent member to facilitate the insertion of a tool to release the same.

References Cited in the file of this patent UNITED STATES PATENTS Re. 4,114 Anderew Sept. 6, 1870 201,719 T. Taylor Mar. 26, 1878 450,115 W. Taylor Apr. 7, 1891 1,825,264 Dexter Sept. 29, 1931 2,517,240 Roberts Aug. 1, 1950 FOREIGN PATENTS 601,485 Germany Aug. 16, 1934

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