US3608939A

US3608939A - Convertible latch set

Info

Publication number: US3608939A
Authority: US
Inventors: Stuart G Mcburnie; William G Fortt; Michel L E Rocher
Original assignee: VELTO INDUSTRIES Ltd
Current assignee: VELTO INDUSTRIES Ltd
Priority date: 1969-09-17
Filing date: 1969-09-17
Publication date: 1971-09-28
Anticipated expiration: 1988-09-28
Also published as: SE381701B; DE2045865B2; ZA706151B; DE2045865A1; ES199646Y; CA921512A; FR2062258A5; BE756306A; JPS4919678B1; ES199646U; CH526710A; NL7013680A; GB1266668A

Abstract

A latch set having a locking slide which is movable from a disengaged position, in which a latch mechanism can be actuated by rotation of either door handle, to an engaged position, in which the latch set and therefore the door are locked. The locking slide is adjustable relative to associated parts whereby the latch set can selectively be installed as either a privacy set which will lock the door, or as a passage set which will merely latch but not lock the door, with either one of the alternate installations being adapted for later conversion to the other.

Description

United States Patent Inventors Burnaby;

Stuart G. McBurnie William G. Fortt, Port Coquitlam; Michel L. E. Rocher, Vancouver, all of British Columbia, Canada Appl, No. Filed Patented Assignee Sept. 17, 1969 Sept. 28, 1971 Velto Industries Ltd.

Vancouver B. C., Canada Primary Examiner-[an A. Calvert Assistant Examiner-Edward J. McCarthy Attorney Fetherstonhaugh & Co.

' ABSTRACT: A latch set having a locking slide which is mova ble from a disengaged position, in which a latch mechanism can be actuated by rotation of either door handle, to an engaged position, in which the latch set and therefore the door are locked. The locking slide is adjustable relative to associated parts whereby the latch set can selectively be installed as either a privacy set which will lock the door, or as a passage set which will merely latch but not lock the door, with either one of the alternate installations being adapted for later conversion to the other.

CONVERTIBLE LATCH SET 9 Claims, 14 Drawing Figs.

U.S. Cl 292/254, 292/341.18, 292/359 Int. Cl ..Eb /02, EOSb 13/00 Field of Search 292/254, 391.18, 348, 350, 227, 169, 177,182, 336.3, 359; /222, 223

95 6 4s, 3 86 7 9s l 1' 74 8| 5 72- l i e0 e2 52 3 L. r 1 l l l I l 16A PATENTEU SEP28 |97l LT: fi- I20} SHEET 3 BF d INVINTOI S TU A R T 6 Me BURNIE WILLIAM G. FORTT MICHEL L. E. ROCHER ATYOINRYS PATENTEDSEP28I97I 3608.939

SHEET .3 BF 4 IMVINTOIS STUART 6. McBURNIE WILLIAM G. FORTT MICHEL L. E. ROCHER ATTOINIYQ PATENTED SEP28 I97! SHEET u 0F 4 INVINTO STUART 6. McBURNIE WILLIAM G. FORTT MICHEL L. E. ROCHER "wanna CONVERTIBLE LATE SIE'I BACKGROUND OF THE INVENTION This invention relates to door latch sets and more particularly to a dual-purpose door-latching apparatus.

A conventional latch set is designed specifically to serve either as a privacy set which will look a door, or as a passage set for a door which need not be locked. In either case, the mechanism is a complex and relatively expensive item made up of a very large number of precision-made metal parts. The design of the set must be varied somewhat to suit a particular installation, i.e., the door for which the set is mounted may be a thin passage door or a heavy and relatively thick outer door requiring a burglarproof lock, and such variation in design all adds to the manufacturing cost and therefore the eventual cost to the consumer. Other disadvantages of conventional latch sets are that they are best installed by a skilled carpenter who must take great care to determine the exact location on the door and doorframe for the various holes and recesses to receive the set. If even a small error is made during installation, the latch set may fail to function properly and, if the error is a large one, the door may be ruined.

SUMMARY OF THE INVENTION The present latch set has approximately one-fifth the number of parts of a conventional set and all but a few of these parts are made from a strong, durable and corrosion-free plastic. This provides a silently operating mechanism of an extremely versatile design which is suitable for installation on almost any thickness of residential door. By a simple adjustment which can be performed by most householders, the set can be converted from a privacy set to a passage set or vice versa. If the holes drilled in the door and the recesses formed in the jamb are not precisely located, the set will compensate for such errors. An adjustment can be made to a part of the set which will allow variation in the spacing from the edge of the door to the axes of the door handle. If it is found that the jamb and door parts are not aligned properly during installation, another adjustment to a jamb part will ensure that the door in held firmly so that it will not rattle. The set can be locked and unlocked by a simple push-pull motion of the inside handle which is positive in its action. Once the set if locked it cannot be vibrated to an unlocked position by manipulation of the outside handle and the possibility of forced entry is reduced to a minimum by the locking arrangement of the extremely strong and slightly flexible plastic parts of the latch set.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. l is a horizontal section of a convertible latch set, in accordance with the present invention,

FIG. 2 is a transverse section taken on the line 2-2 of FIG.

FIG. 3 is a transverse section taken on the line 3-3 of FIG.

FIG. 4i is still another transverse section taken on the line d-d of FIG. 1,

FIG. 5 is a perspective view of the locking slide of this latch set,

FIG. 6 is an elevation looking into the open end of a handle knob of the latch set and showing a lock collar therein,

FIG. 7 is an elevation of a lockwasher adapted to fit in the handle knob of FIG. 6,

FIG. 8 is an elevation of the shaft and the locking slide as these parts are seen from the left of FIG. I,

FIG. 9 is a perspective view of the door strike used in this set,

FIG. It] is an elevation, part in section, of the outer face of the latching mechanism carried by the doorjamb, and taken on the line iii-Ill) of FIG. 1,

FIG. llll is a vertical section taken on the line III-11 of FIG. 10,

FIG. 12 is a section taken on the line H2-12 of FIG. ill and showing the inner faces of the keeper plate and keeper in elevation,

FIG. 13 is a plan of the release pin for the set, showing the shaft and locking slide in dotted lines with said slide in the innermost position,

FIG. M is a section taken on the line lld- M of F [6, l3.

DESCRIPTION OF THE PREFERRED EMBODIMENT The several parts of the latch set which is about to be described are made almost entirely of a suitable hard-wearing plastic material which has many well-known advantages over metal. The only exceptions to the use of plastic are a few fasteners which are made of metal. By way of example, the set will be described as being used on lid-inches bathroom door although it will be understood the set can be used on most household doors with only slight adjustment to a few parts of the set. Since the bathroom door obviously has to be locked from the inside, the set will be illustrated and described installed as a privacy set for later conversion to a passage set.

Referring to FIG. ll of the drawings, the numeral indicates generally a bathroom door having a face llll which is on the outside of the room, a face 112 on the inside of the room, and a side edge 14. At a suitable spacing from the edge M, the door is drilled to provide a transversely extending, horizontal hole 115. The door edge M is drilled to provide a relatively small horizontal hole 116 which communicates with the large hole l5 and is disposed at right angles thereto. A recess lid is formed in the door edge M and the longitudinal axis of the small hole 16 intersects this recess at midheight. Recess 15 opens out to the face 11 of the door and is spaced a short distance from the face 12.

The door it) is hung in the usual manner within a frame having a jamb 20. A vertical abutment strip 2ll is provided on edge 22 of the jamb 20, on the outside of the doorframe, to serve as a stop for the door Ml. Another slightly larger recess 23 is formed in the edge 22 of the jamb, this recess also being intersected at midheight by the axis of the hole l6. Recess 23 extends from the strip Zll to the inside face 24 of the door jamb.

The drilling of the above-mentioned holes and the formation of the two recesses prepares the door 10 and jamb 20 to receive the present latch set which is generally indicated by the numeral 30. Latch set 30 comprises a housing 31 formed of an inner sleeve 32 and an outer sleeve 33. The inner sleeve 32, see FIGS. 1 and 2, has an end plate 35 in which a central opening 36 is formed and this opening is bordered by an outwardly projecting circular flange 37. Sleeve 32 is externally threaded as at 39, the thread preferably being a square thread, and a rectangular opening 450 is formed in one side of the sleeve. On the inner face of the end plate 35, there are two diametrically opposed pins 42 (FIG. I.) which are parallel to the longitudinal axis of the sleeve 32.

Referring to FIG. l the outer sleeve 33 will be seen to have an end plate 35A, and a central opening 36A is formed in this plate with a circular flange 37A surrounding said opening. Sleeve 33 is internally threaded as at 39A to engage the thread 39 on the inner sleeve.

The

telescoping sleeves

32 and 33 are threaded together within the large hole 15 in the door to draw their

end plates

35 and 35A into clamping engagement with the opposing faces Ill and 112 of the door. As plate 35 is clamped to the door face ill, the pins 42 are embedded slightly in the wood of the door so that the housing 31 cannot rotate. The rectangular opening ilt) of sleeve 32 registers with the small] hole 16 when the housing is properly mounted in the door. It will be noted the

sleeves

32 and 33 can be tightened by hand to a degree which requires the use of a special tool to release them from their gripping engagement with the door. The door faces ill and 12 may not be parallel to one another or may be unevenly finished or painted but the

plastic end plates

35 and 35A will compensate for such defects in the door. As the housing sleeves are tightened, the outer edges of the

plates

35 and 35A are caused to flex slightly to conform to the door surfaces. The natural tendency of the plastic is to cling to the wooden door and the flexed outer edges of the end plates of the

sleeves

32 and 33 exert resilient pressure on the door faces which augments the clinging action of the plastic and all this strongly resists any tendency of said sleeves to counterrotate. Thus, the innerand outer sleeves of the housing 31 will remain firmly threaded together under all normal circumstances with no other fastening devices being required.

Mounted within the housing 31 is a shaft 44 which is shaped somewhat like a cross when viewed from either end. Shaft 44 has an outside end 45, an inside end 46, and an intermediate portion 47. The crosslike shape of the shaft 44 provides end 45 with longitudinally extending enlarged splines 49, see FIGS. 2 and 5, and on the peripheries of these splines an interrupted thread 50 is cut, which thread preferably is a double start, square thread. The outside diameter of end 46 is slightly less than the corresponding diameter of end 45 and the particular shape of the shaft provides the inside end 46 with splines 52 (FIG. 3) which are aligned with the splines 49 on the threaded end. As shown best in FIG. 4, the intermediate portion 47 of the shaft has longitudinal ribs 54 which project.

radially outwardly beyond the splines 49.

Threaded end 45 of the shaft is fitted with a hollow handle knob 58, see FIG. 1, which knob 58 has an inner end wall 59, a slightly tapered peripheral wall 60,-and an internally rebated outer end 61. An internally threaded opening 63, is formed in wall 59 and an inwardly projecting and circular flange 64 is provided on said end wall to encircle said opening. Knob 58 is threaded on to the shaft end 45 and the flange 64 is seated within the flanged opening 36 of the end plate with the wall 59 in contact with the flange 37. Thus, the handle knob 58 is rotatably supported by the plate 35 and is held against side and end play. This particular mounting of the handle knob serves to journal the threaded end of the shaft 44.

The inside end 46 of the shaft is fitted with a locking slide 68, see particularly FIG. 5, this tubular slide being in the form 1 of an open cross when viewed in end elevation. The slide 68 has longitudinal splines 69 which extend from the outer end of said slide to a flange 70 on the inner end thereof. Slide 68 has a splined bore 72 which is shaped to closely fit the splines 52 on the shaft so that said slide cannot rotate on the shaft but is free to slide longitudinally thereof. The outer peripheries of the splines 69 are provided with an interrupted, double start, square thread 74. Preferably, one of the splines 52 is made slightly smaller than the other three splines on shaft portion 47. The splined bore 72 of thejslide is correspondingly shaped so that the slide 68 will only fit one way on the shaft 44. This ensures that the slide 68 is always correctly positioned in relation to the intermediate portion 47 of the shaft for reasons which will be made apparent later.

An inside handle knob 78, see FIGS. 1, and 3, and 6, is threaded on to the locking slide 68. This hollow knob 78 is identical to knob 58, viz. it has a peripheral wall 79, an end wall 80, an internally threaded opening 81, and a flange 82 surrounding said opening. Wall 79 has a rebated outer end 83, see FIG. 1 only. The flange 82 enters the opening 36A in the end plate 35A and is closely confined by the flange 37A. The hollow knob 78 then is joumaled and held against end play by the adjacent end plate in the same manner as the outside handle knob. This arrangement rotatably supports the inside end 46 of the shaft so that said shaft can be turned by rotation of either of the handle knobs once the latter members are locked to the former; At the same time, the knob 78 and the slide 68 have limited endwise movement on the shaft 44 with the extent of this movement being variable as will be explained in detail later.

It will be noted that the parts thus far described can be assembled in almost any thickness of door likely to be found in a home or other building. The housing 31 is extended or contracted as required by the door thickness and the two handle knobs are threaded into engagement with their respective end plated. If the door is very thin for example, the opposite ends of the shaft 44 simply project a greater than normal distance into the hollow handle knobs.

Locking means, generally indicated at 86,'is provided to secure the inside handle 78 to the slide 68. As shown in FIGS.

1, 6 and 7, locking means 86 comprises a collar 87, see par-' ticularly FIG. 6, which is secured to the wall 80 within the handle knob. Collar 87 has a suitable number of radially projecting tabs 88 which serve, in part,- to define arcuate recesses 89. Preferably, there are as many as 16 of these recesses 89 to provide a very fine degree of adjustment for the locking means 86, but for convenience, a lesser number are shown in the drawings. One of the tabs 88 is aligned-with a pilot pin 90 which extends outwardly along the inner surface of the wall 79 and is suitably secured thereto.

A washer 94,see FIGS. 1 and 7, cooperates with the collar 87 to secure the knob 78 to the slide 68. In FIG. 7 particularly,

the washer 94 is shown as having a cross-shaped or splined opening 95 which conforms to the cross-sectional shape of the splined slide 68. Spaced around the outer edge of the washer 94 are a number of inwardly projecting lugs 96. The number and shape of the lugs 96 conform to that of the recesses 89 formed within knob 78. Also formed on the washer 94 are a pair of circumferentially spaced prongs 98 which project outwardly from the washer parallel to the axis of the opening 95. These prongs 98 are for convenience in manipulating the washer 94 as it is fitted into or removed from the knob 78.

When the present latch set is installed as a privacy set as in this example, the locking slide 68, and the handle knob 78 attached thereto, are provided with a predetermined amount of end play and this is done by adjustment of the locking means 86. Prior to fitting the means 86 in position, knob 78 is threaded to a position on the slide 68 which will allow said slide to be moved along shaft 44 from an outer position, as shown in FIG. 1, an inner position spaced inwardly a little from said outer position. These inner and outer positions are the locked and unlocked positions respectively of the latch set 30.

Once the inside handle knob 78 has been threaded to the required position on the slide 68, the washer 94 is fitted over the splined and threaded end of said slide, which end then projects into the hollow knob, and is pushed inwardly. until the lugs 96 are lodged in the recesses 89 of the collar 87. As this is done, the pilot pin passes between two of the lugs 96 on the washer to serve as a guide which helps to prevent the washer 94 from binding on the peripheralwall 79 of the handle knob as said washer is moved inwardly. When thecollar 87 and washer 94 are fully engaged, the handle knob 78 is locked firmly to the slide 68. The slide 68 in turn is splined to the shaft 44 so that the three interlocked parts can only be rotated as a unit.

The outside handle knob 58 is secured against rotation on threaded end 45 of the shaft by an identical locking means generally indicated at 101 and shown in FIG. 1 only. Briefly, means 101 comprises a similar collar 102, and a similarly shaped washer 103. The collar 102 and washer 103, when engaged as previously described, prevent the outside handle knob 58 from rotating on the thread 50. Thus, the outside and inside handle

knobs

58 and 78 are locked to the shaft 44 and the locking slide 68, which slide is splined to' the shaft 44 so that said shaft can be rotated by turning either handle knob in either direction when the slide 68 is in the outer or unlocked position.

Referring again to FIG. 1, the numeral 106 indicates a shim which is fitted to the slide 68 when the present latch set is installed on a 1% door. The shim 106 in this particular installation is-three-eighths of an inch thick with an outside diameter substantially equal to that of the flange 70 on the locking slide. A cross-shaped opening 107 is formed in the shim 106 and the dimensions of this opening are such that it will closely fit over the splines 69 on the slide. Shim 106 normally is held in contact with the flange 70 and, when the slide 68 is in the outer or unlocked position shown in FlG. 1, said shim also is in contact with a shoulder 109 on the inner face of the end plate 35A. Thus, a stop is provided which limits the outward movement of the handle knob 78 and therefore the locking slide 68 as well. If the latch set 30 was installed on a l t inches door for example, the shim 106 would be omitted in which case the flange 70 would contact shoulder 109 to limit outward movement of the slide and knob. By substituting a shim of appropriate thickness, or omitting a shim altogether, the present latch set can be made to function properly in a wide variety of doors.

The handle knob 58 is fitted with a cover 112, see FIG. 1. Cover 112 is a concave-convex disc of flexible plastic and has a diameter to closely fit within the rebated end 61 of the handle knob. Cover 112 is inserted into end 61, convex side out and finger pressure is applied to snap the plastic disc inwardly whereupon the convex side projects inwardly. This attaches the cover 112 securely to the handle knob 58 so that it can only be removed by use of a special tool.

The inside handle knob 78 is fitted with a similar cover 116 which is seated in the rebated end 83 of this handle knob. Cover 116 is installed and locked in position in the previously described manner.

Stop means, generally indicated at 120, see particularly FIGS. 4, 5 and 8, is provided between the housing 31 and the shaft 44 to prevent rotation of said shaft. As shown in these particular views of the drawing, means 120 comprises a key 122 which is integrally formed on the inner surface of the sleeve 32. The flange 70 has a keyway 123 and the key 122 enters this keyway (FIG. 8) when the slide 68 is moved inwardly to the inner or locked position. When the inner end of the key 122 is entered into the keyway 123 in this manner, the shaft 44 cannot be rotated and the set therefore is locked. Stop means 120 is released when the slide 68 is withdrawn to the outer or unlocked position shown in FIG. 1, which movement allows the shaft 44 to be rocked by turning either door handle knob.

Referring now briefly to FIG. 4, key 122 will be seen to be located midway between the ribs 54 of the intermediate portion 47 of the shaft when said shaft 44 is in a normal or unrotated position. Whenever the shaft is rotated by means of a handle knob, then one or the other of the ribs 54 is moved into contact with the stationary key 122 and the key then acts as a stop to limit the rotation of the shaft.

The present latch set is provided with gripping means, generally indicated at 126, which resists movement of the slide 68 to disengage the stop means 120. As shown best in FIG. 5, the means 126 comprises a number of circumferentially spaced lugs 127 which are integrally formed on the flange 70 to project inwardly thereof. The spacing between the lugs 127 is slightly less than the width of the ribs 54 on the intermediate portion 47 of the shaft. Since both of these lugs 127 and the ribs 54 are formed of a tough and durable plastic material both the lugs and the ribs will yield very slightly when engaged so that the wedging action is achieved. The natural tendency of the plastic parts is to cling to and resist separation from one another so that the slide 68 is held to the shaft 44 by the force of friction and a little effort must be exerted to separate the said parts. Thus, if the outer handle knob 58 was pounded or rattled when the door was locked, there would be little likelihood of the slide 68 being vibrated out of engagement with the ribs 54, to release the stop means 120.

The convertible latch set 30 includes a latching mechanism which is generally indicated at 130. As shown in FIGS. 1 and 9, mechanism 130 comprises a strike 132 which is a rectangular plastic plate set into the recess 18 in the door edge 14. Strike 132 is secured within the door recess by metal screws 133 shown in FIG. 9 only. The strike 132 has a rectangular recess 135 which is inwardly tapered to provide a vertical shoulder or stop 136 near the face 11 of the door. Formed in the center of the recess 135, is an opening 138 which registers with the hole 16 in the door.

Also forming part of the latching mechanism 130 is a boxlike frame 140 (FIGS. 1, and 11) which is set into the recess 33 in the door jamb. Frame 140 has an inner wall 141 and a sidewall 142, the latter wall being flush with the inside edge 24 of the jamb 20, see FIG. 1. Metal screws 144 extend through wall 141 to secure the frame 140 to the jamb and within the recess 23.

Mounted within the frame is a substantially rectangular keeper plate 150, see FIGS. 1, 10, 11 and 12. Plate has a central, rectangular opening 152 and horizontal slots 153 spaced above and below said opening. The screws 144 project through the slots 153 so that the keeper plate 150 has limited lateral movement within the frame 140 when said screws are backed off slightly.

A boxlike keeper is mounted within the opening 152 of the plate 150. As shown in FIGS. 10, 11 and 12, vertically disposed pintles 161 are provided at the inside edge 162 of the keeper 160. These pintles 161 are journaled in sockets 164 formed in the plate 150 so that the keeper 160 can swing about the common vertical axes of said pintles to the out wardly inclined position shown best in FIGS. 1 and 11. Edge 165 of the keeper plate to limit outward swinging movement of said keeper and this prevents free edge 167 of the keeper from projecting too far beyond the edge 22 of the jamb.

A small plastic tensioner 170 (FIGS. 11 and 12) is secured to the left edge (FIG. 12) of the keeper plate 150 so as to pro ject across opening 152. The free edge 170A of the tensioner bears against the pivoted side of the keeper 160 to urge said keeper outwardly of the opening 152. Thus, the normal position of the keeper 160 is projecting outwardly at an acute angle to the edge 22 of the jamb. This places the free edge 167 of the keeper within the recess 135 of the strike 132 when the door 10 is closed. The stop 136 is engaged by the keeper edge 167 whereupon the door is held latched until the keeper is pushed inwardly.

When the door and door jamb are prepared for the latch set, it may be that the hole 16 and the recess 23 are not properly aligned and, to compensate for this, the present invention is provided with adjustable means 174 for moving the keeper 164) towards and away from the stop 136 and for securing said keeper in a selected position relative to said stop. Referring again to FIGS. 10, 11 and 12, the means generally indicated at 174 is shown to comprise a pair of adjusting bolts 175, there preferably being one such bolt at the top and one at the bottom of the frame 140. Frame 140 is provided with sockets 176 at the outer corners thereof (FIG. 10) and the heads 177 of the bolts are journaled in these sockets. Sidewalls 142 of the frame has openings 178 and the slotted ends 179 of the bolts are rotatably mounted within these openings.

The adjusting bolts 175 are engaged by threaded parts 181, see FIG. 12, which parts are half-nuts formed along the top and bottom edges of the keeper plate 150. The screws 144 hold the parts 181 in threaded engagement with the bolts 175 so that when these bolts are rotated, plate 150 is caused to move along said bolts.

To adjust the position of the keeper 160 by use of the means 174, a small screwdriver (not shown) is inserted into the slotted ends 179 and the bolts 175 are rotated in the appropriate direction to move the free edge 167 of the keeper into proper contact with the stop 136 on the strike. The screws 144 are slackened very slightly to allow this transverse movement of the keeper to take place and when said screws are retightened, the keeper 160 is secured against movement away from the adjusted position.

Mounted in the small opening 16, is a pressure pin generally indicated at 185. As shown best in FIG. 4, pressure pin 185 has an inner part 186 and an outer part 187 which parts are threaded together at 188. Outer end or tip 190 of the pin 185 projects into the opening 138 in the door strike. A shoulder 192 is formed on the outer end of part 187 of the pressure pin and butted against this shoulder and another shoulder 193 formed on the strike 132, is a short compression spring 194. Spring 194 provides means for biasing the pressure pin 185 away from the latching mechanism 130 and towards the shaft 44.

The construction of the pressure pin 185 is such that the pin can be shortened or lengthened as required according to the distance the axis of the large hole 15 has been set back from the edge 14 of the door. Sometimes it is desirable to vary this back set slightly from one door to another and it may happen that the person installing the set will miscalculate and drill the hole not exactly in the right place in which case, the pressure pin 185 can be adjusted accordingly and a properly functioning latch set is ensured.

Drive means 201 is provided between the intermediate portion 47 of the shaft 44 and the pressure pin 185. As shown best in FlG. 4, the drive means 201 comprises a pair of inwardly dished cams 202 which are formed on the shaft beneath the ribs 54. The inner part 186 of the pressure pin is provided with forks 204 which project into operative engagement with the cams 202. Between the forks 204, the pin 185 is shaped to conform to the shape of the shaft portion 47 and particularly with the splines 52 which extend across this portion of the shaft. Thus, whenever the shaft is rotated in either direction, the pressure pin 185 is caused by the drive means 201 to move away from the shaft and the spring 194 is compressed. The tip 190 of the pressure pin is projected from the opening 138 and into contact with the keeper 160 so that said keeper is pushed out of engagement with the stop 136 on the strike. Thus, the door is unlatched and when the door is swung open, the keeper 160 is snapped outwardly once again by the tensioner 170 ready to relatch the door when it is shut. It should be noted the plastic parts making up the drive means 201 and latching mechanism 130 all operate in almost complete silence and without the need for lubrication.

The door is locked by pushing the inside handle knob 78 inwardly to dispose slide 68 in its inner position whereupon the key 122 enters the keyway 123 of flange 70 and the lugs 127 grip the ribs 54 on the shaft. The outside handle knob 58 cannot be rotated to unlatch the door nor can the inside handle knob 78 be so rotated until it is first pulled away from the inside door face 12.

The latch set has been described as used in a bathroom door and it is desirable that such a door have some means for releasing the lock from the outside of the room. FIGS. 13 and 14 show such a means generally indicated at 210 and comprising a release pin 21] which has a disclike head 212 and a tip 213. Head 212 is disposed at right angles to the pin 211 angles to the pin 211 and preferably a web 214 interconnects and strengthens these two parts.

The outer end 45 of the shaft has a recess 215, see particularly FIG. 14. A longitudinal channel 216 is formed on the periphery of the shaft 44 to extend along both the end 45 and portion 47.

The release pin 211 is lodged in the channel 216 with the head 212 being enterable into the recess 215. Web 214 of the release pin is received in the recess 215. Thus, the release pin 211 is slidably and nonrotatably supported by the shaft 44. The head 212 extends across end 45 of the shaft while the tip 213 is positioned alongside the flange 70 on the locking slide.

Referring now to FIG. 1, the cover 112 for the outside handle knob 58 will be seen to have a central aperture 225. This aperture is intended to admit a needlelike tool 226 which is pushed inwardly until it contacts the head 212 of the release pin. A slight additional push on the tool 226 will move the release pin endwise and this in turn will cause the tip 213 to engage flange 70 and push the locking slide 68 away from the inner position (FIG. 8) to the outer position (FIG. 1). Movement of the slide 68 to the outer position will disengage the stop means 120 and unlock the latch set. Thus, if a child or anyone else is locked in the bathroom, the door can be opened bathroom, the door can be opened as described.

From the foregoing, it will be apparent the convertible latch set has many features and advantages over conventional metal sets. A home builder for example, can buy a number of the present sets and install them wherever required through the house regardless of the door thickness. When the device is installed as a privacy set as described above, it is a simple matter later on to convert it to a passage set. This is done by removing the cover 116 and lockwasher 94 so that the inner handle knob 78 can be advanced on the threads 74 of the locking slide. The slide 68 is positioned by this adjustment of the handle knob 78 so that it cannot be moved in and out as it is required to be moved to engage the stop means 120 and lock and unlock the door. in other words, the slide 68 is secured against endwise movement but the shaft 44 can still be rotated by either handle knob and the latch set thus is converted to a simple passage set. If the present set is installed originally as a passage set it is equally as simple to convert it to a privacy set should the need ever arise.

We claim:

1. A convertible latch set comprising a housing mountable to extend through a large hole formed in a door, said housing having end plates nonrotatably engaging opposite faces of the door, a shaft extending longitudinally through the housing and through openings in the end plates, a first handle knob secured to one end of the shaft and being rotatably supported by an adjoining end plate, a locking slide nonrotatably mounted on an opposite end of the shaft, a second handle knob nonrotatably mounted on the locking slide and being rotatably supported by an adjoining end plate, said locking slide being movable by the second handle knob from an inner locked position to an outer unlocked position, a pressure pin mounted for endwise movement in a relatively small hole extending into the door edge normal to and connecting with the large hole, drive means between the pressure pin and the shaft, a latching mechanism mountable in an edge of the door and in a door jamb normally engaged to retain the door in closed position, said shaft being rotatable by the handle knobs when the locking slide is in the outer unlocked position to move the pressure pin to engage and release the latching mechanism, stop means between the housing and the locking slide engaged when said locking slide is in the inner locked position to prevent rotation of the shaft, said stop means comprising a key carried by the housing, said locking slide having a keyway to receive the key when the locking slide is moved to the inner locked position, and including circumferentially spaced ribs on said shaft, said key projecting between the ribs and cooperating therewith to limit rotation of said shaft.

2. A convertible latch set as claimed in claim 1, in which said latching mechanism comprises a stop on the edge of the door, a keeper mounted in the doorjamb opposite the pressure pin for swinging movement about a vertical axis, spring means biasing the keeper to an outwardly inclined position whereby a free edge of said keeper will engage the stop when the door is closed, and adjustable means for moving the keeper towards and away from the stop and securing said keeper in a selected position relative to said stop, said adjustable means comprising a frame secured to the doorjamb, a keeper plate mounted in the frame for limited horizontal movement, said keeper being mounted as aforesaid within the keeper plate, an adjusting bolt journaled by the frame, said keeper plate having a threaded part in operative engagement with the adjusting bolt.

3. A convertible latch set as claimed in claim 1, and including gripping means frictionally securing the locking slide to the ribs and resisting endwise movement of said locking slide to disengage the stop means.

4. A convertible latch set as claimed in claim 3, in which said gripping means comprises circumferentially spaced lugs mounted on the locking slide to engage the ribs on the shaft.

5. A convertible latch set as claimed in claim 3, and including a release pin carried by said one end of the shaft for endwise movement thereon, said first handle knob being hollow and having an outer end cover provided with an aperture, said release pin being adapted to be moved endwise to disengage the stop means by a needlelike tool entered through the aperture.

6. A convertible latch set as claimed in claim 5, in which said release pin has a disc at one end thereof, said one end of the shaft having a longitudinal channel extending along the periphery thereof, said release pin being slidably mounted in the channel with the disc extending across the end of the shaft for engagement by the needlelike tool.

7. A convertible latch set as claimed in claim 1, and including spring means biasing the pressure pin away from the latch mechanism.

8. A convertible latch set as claimed in claim 7, in which locking slide, said locking means being adjustable to allow the Said Pressure P has an inner P and an outer Part, Said second handle knob to be selectively positioned on the locking inner and outer parts being threadedly connected together to permit the pressure pin to be varied in length.

9. A convertible latch set as claimed in claim 11, and including locking means securing the second handle knob to the slide whereby to retain said locking slide in the outer unlocked position.

Claims

8. A convertible latch set as claimed in claim 7, in which said pressure pin has an inner part and an outer part, said inner and outer parts being threadedly connected together to permit the pressure pin to be varied in length.

9. A convertible latch set as claimed in claim 1, and including locking means securing the second handle knob to the locking slide, said locking means being adjustable to allow the second handle knob to be selectively positioned on the locking slide whereby to retain said locking slide in the outer unlocked position.