Door locking device
United States Patent 3922896
An actuator rod extending between a pair of knobs on the inside and the outside, respectively, of a door is normally rotatable by both knobs to cause the usual latch bolt of the door to be thrown back. The inside knob has a push button upon depression of which a first clutch of claw type connecting the outside knob to the actuator rod is disengaged. The outside knob has a built-in cylinder lock assembly associated with a second clutch of tongue-and-groove type to permit the door to be opened from the outside while the push button is held depressed. Upon manipulation of the cylinder lock key the second clutch engages to connect the outside knob to the actuator rod. Cam means is employed by way of operative connection between the second clutch and the "plug" or cylindrical rotor of the cylinder lock assembly.
US Patent References:
Spindle assembly
Waldo - May 1929 - 1714286
Knob or handle lock
Keeler - May 1931 - 1804781
/1876576.html
Arste - September 1932 - 1876576
Automobile door handle
Lowe - July 1933 - 1918411
Door lock
Milligan - October 1948 - 2450840
Spindle assembly
Waldo - May 1929 - 1714286
Knob or handle lock
Keeler - May 1931 - 1804781
/1876576.html
Arste - September 1932 - 1876576
Automobile door handle
Lowe - July 1933 - 1918411
Door lock
Milligan - October 1948 - 2450840
Application Number:
05/550961
Publication Date:
12/02/1975
Filing Date:
02/19/1975
View Patent Images:
Export Citation:
Assignee:
Yoshida Kogyo K.K. (Tokyo, JA)
Primary Class:
Other Classes:
70/149, 70/218
International Classes:
E05B55/14; E05B13/10; E05B55/10; E05B63/18
Field of Search:
70/146,147,149,156,218,223,DIG.3 292/169
US Patent References:
| 2497328 | Door latch | February 1950 | Smith et al. |
Primary Examiner:
Gilliam, Paul R.
Assistant Examiner:
Pietruszka, Carl F.
Attorney, Agent or Firm:
Bucknam, And Archer
Claims:
What is claimed is
1. In a door locking device, the combination of:
2. a driving member fixedly supported by said outside knob for simultaneous rotation therewith, said actuator rod projecting into said outside knob by rotatably and longitudinally movably extending through said driving member; and
3. a driven member fixedly mounted on the other end of said actuator rod projecting into said outside knob, said driving and driven members of said first clutch being interengageable only when said actuator rod is in said first position to permit said actuator rod to be rotated by said outside knob;
4. a driving member fixedly mounted on said slide for simultaneous rotation therewith; and
5.
6. a driven member formed at said other end of said actuator rod, said driving and driven members of said second clutch being interengageable only when said actuator rod is in said second position and said slide in said fourth position to permit said actuator rod to be rotated by said
7. The combination as set forth in claim 1, wherein said cam means comprises a first cam element fixedly mounted on said rotor of said lock assembly for simultaneous rotation therewith, and a second cam element fixedly mounted on said slide in opposed relationship to said first cam element, said first and second cam elements having mating jaw-like portions, respectively, whereby said second cam element is movable with said slide away from said first cam element due to the bias of said spring means when said rotor is rotated in said predetermined direction, and back to said first cam element against the bias of said spring means when said rotor is rotated in said opposite direction.
8. The combination as set forth in claim 1, wherein said driving and driven members of said second clutch have surfaces opposed to each other and have formed thereon a tongue and a groove, respectively, said tongue being engageable in said groove when said actuator rod is in said second position and said slide in said fourth position.
1. In a door locking device, the combination of:
2. a driving member fixedly supported by said outside knob for simultaneous rotation therewith, said actuator rod projecting into said outside knob by rotatably and longitudinally movably extending through said driving member; and
3. a driven member fixedly mounted on the other end of said actuator rod projecting into said outside knob, said driving and driven members of said first clutch being interengageable only when said actuator rod is in said first position to permit said actuator rod to be rotated by said outside knob;
4. a driving member fixedly mounted on said slide for simultaneous rotation therewith; and
5.
6. a driven member formed at said other end of said actuator rod, said driving and driven members of said second clutch being interengageable only when said actuator rod is in said second position and said slide in said fourth position to permit said actuator rod to be rotated by said
7. The combination as set forth in claim 1, wherein said cam means comprises a first cam element fixedly mounted on said rotor of said lock assembly for simultaneous rotation therewith, and a second cam element fixedly mounted on said slide in opposed relationship to said first cam element, said first and second cam elements having mating jaw-like portions, respectively, whereby said second cam element is movable with said slide away from said first cam element due to the bias of said spring means when said rotor is rotated in said predetermined direction, and back to said first cam element against the bias of said spring means when said rotor is rotated in said opposite direction.
8. The combination as set forth in claim 1, wherein said driving and driven members of said second clutch have surfaces opposed to each other and have formed thereon a tongue and a groove, respectively, said tongue being engageable in said groove when said actuator rod is in said second position and said slide in said fourth position.
Description:
BACKGROUND OF THE INVENTION
This invention relates generally to locks and more specifically to a door locking device. Still more specifically, the invention deals with a door locking device of the type comprising a pair of knobs rotatably supported on the inside and the outside, respectively, of a door, and an actuator rod which is normally rotatable by both knobs to cause, for example, a latch bolt to be withdrawn into the door. The inside knob has a push button which is depressible to disengage the outside knob from the actuator rod and hence to render the door un-openable from the outside unless a key is manipulated in a lock assembly built into the outside knob.
Some prior art door locking devices of the type under consideration have a drawback in common with regard to the means for permitting the door to be opened from the outside by use of a key while a push button or the like on the inside knob is held depressed or otherwise actuated. A typical example of such prior art devices includes what may be termed an unlocking cylinder mounted within a sleeve which is integral with the outside knob. When the key is turned in the outside knob, the unlocking cylinder rotates and travels toward the inside of the door as guided by helical grooves on the internal surface of the sleeve. The unlocking cylinder has a groove which is intended to engage, at the end of the inward stroke of the cylinder, a tongue on a member rotatable with an actuator rod so that the door may be opened by the turn of the outside knob.
The door can of course be unlocked if the groove correctly engages the tongue at the end of the inward stroke of the unlocking cylinder. However, in event the angular position of the rotatable unlocking cylinder at the end of its inward stroke is not exactly adjusted to that of the tongued member, the door is not openable by the succeeding turn of the outside knob. The key must then be manipulated again after rotating the outside knob through a suitable angle in order that correct interengagement may result between tongue and groove. Not only is this unlocking procedure troublesome, but the repetition of the procedure can cause premature wear or damage to the contacting surfaces of the unlocking cylinder and tongued member. The door may eventually become unlockable from the outside.
SUMMARY OF THE INVENTION
It is among the objects of this invention to provide an improved door locking device of such construction that the door can be smoothly and positively unlocked from the outside by a key, practically without any undue stress exerted on the working parts of the unlocking mechanism.
With the above and other objects in view, this invention provides a door locking device including an actuator rod which extends between inside and outside knobs and which is normally rotatable by both knobs to actuate the usual latch bolt of the like so that the door may be opened from either the inside or the outside. The device further comprises a first clutch which normally connects the outside knob to the actuator rod and which disengages upon depression of a push button on the inside knob, and a second clutch which engages to connect the outside knob to the actuator rod only when a lock assembly built into the outside knob is operated by a key while the first clutch is held disengaged.
The first clutch comprises a driving member fixedly supported by the outside knob for simultaneous rotation therewith, and a driven member fixedly mounted on one end of the actuator rod which projects into the outside knob by rotatably and longitudinally movably extending through the driving member. Upon depression of the push button the actuator rod travels toward the outside of the door so that the driven member of the first clutch moves out of engagement with the driving member.
The second clutch includes a driven member located at the same end of the actuator rod as the driven member of the first clutch. The driving member of the second clutch is fixedly mounted on a slide within the outside knob which is constrained to linear movement toward and away from the driven clutch member. For moving the driving member of the second clutch into and out of engagement with the driven clutch member, cam means is provided between the slide and the lock assembly. The lock assembly may take the form of the well known cylinder lock including a cylindrical rotor which rotates in both directions with the key.
Thus, when the key is manipulated in the lock assembly to rotate the rotor in a predetermined direction while the push button is held depressed, the cam means operates to permit the slide to move, without rotation, toward the driven member of the second clutch by the pressure of spring means. The driving member of the second clutch carried by the slide thus moves into correct engagement with its driven member. The door is now openable from the outside, because then the rotation of the outside knob can be transmitted to the actuator rod via the slide and the second clutch.
The features which are believed to be novel and characteristic of this invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and mode of operation, together with the further objects and advantages thereof, will become apparent from the following description of a preferred embodiment, which is to be read in connection with the accompanying drawings in which like reference characters refer to like parts throughout the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates, partly in perspective and partly in axial section, a door locking device embodying this invention, the view showing a first clutch engaged and a second clutch disengaged, so that the door is openable from either the inside or the outside by the turn of the knobs;
FIG. 2 is a view similar to FIG. 1 but showing both first and second clutches disengaged, so that the door is un-openable from the outside unless a key is used;
FIG. 3 is a fragmentary view illustrating, also partly in perspective and partly in axial section, the door locking device in which the second clutch is shown engaged by the manipulation of the key; and
FIG. 4 is a perspective detail view of cam means used in the door locking device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With particular reference to FIG. 1, the illustrated door locking device includes a pair of generally circular mounting members 10 and 11 fixedly supported on the inside and the outside, respectively, of a door 12 in axial alignment. The mounting members 10 and 11 have axial openings therethrough for rotatably receiving sleeves 13 and 14 which are integral parts of knobs 15 and 16, respectively. It will therefore be seen that these knobs 15 and 16 are rotatably supported by the respective mounting members 10 and 11 with their axes of rotation aligned with each other. The knob 15 is herein termed the inside knob and the knob 16 the outside knob.
A cylindrical guide 17 is closely fitted within the sleeve 13 of the inside knob 15 at its end opposite to the outside knob 16. This guide has a plurality of circumferentially spaced projections 18 which are engaged in corresponding apertures in the sleeve 13, so that the guide is immovable relative to the sleeve. An opening of rectangular cross section extends axially through the guide 17.
An actuator rod 19 of rectangular cross section, adapted to actuate in the conventional manner the usual latch bolt or the like (not shown) operatively mounted in the door 12, slidably extends through the axial opening in the guide 17. The actuator rod 19 is movable longitudinally relative to the guide 17 and hence to the inside knob 15 and is rotatable simultaneously therewith.
At one end of the actuator rod 19, seen to the left in FIG. 1, there is rotatably mounted a push button 20 in axial alignment therewith. The push button 20 includes, or doubles as, a thumbpiece 21 and projects out of the inside knob 15 both rotatably and longitudinally movably relative to the same. The push button 20 has a groove or slot 22 formed in its cylindrical portion within the inside knob 15. The groove 22 is in the shape of an L both limbs of which extend in the circumferential and axial directions, respectively, of the cylindrical portion. A pin 23 projecting radially inwardly from the inside knob 15 is slidably engaged in the L-shaped groove 22. Thus, by turning the thumbpiece 21 in a predetermined direction following the depression of the push button 20, the push button can be releasably held in the depressed position, as will be seen by referring to FIG. 2.
The reference numeral 24 generally designates a first clutch of the so-called "positive" or, more specifically, "claw" type adapted to permit the door 12 to be opened by the turn of the outside knob 16 when the push button 20 is not depressed. The first clutch 24 comprises a driving member 25 fixedly supported within the sleeve 14 of the outside knob 16, and a driven member 26 fixedly mounted on the other end of the actuator rod 19 projecting into the sleeve 14 by rotatably and longitudinally movably extending through an axial opening in the driving clutch member 25.
The driving clutch member 25 has a plurality of circumferentially spaced projections 27 which are engaged in corresponding apertures in the sleeve 14, so that the driving clutch member is immovable relative to the sleeve. The driving and driven clutch members 25 and 26 have claws or teeth 28 and 29, respectively, projecting toward each other for interengagement only when the push button 20 is not depressed.
A helical compression spring 30 is mounted between the driven clutch member 25 and a spring retainer 31 within the sleeve 14 of the outside knob 16. The actuator rod 19 is therefore biased toward the inside of the door 12 via the driven clutch member 25.
The reference numeral 32 generally designates a second clutch of what may be termed a tongue-and-groove type adapted to permit the door to be opened by the outside knob 16 and with the use of a key 33, FIG. 3, when the push button 20 is held depressed. The second clutch 32 comprises a driving member 34 fixedly mounted on a disc-shaped slide or carriage 35 within the outside knob 16, and a driven member 36 formed at the said other end of the actuator rod 19 projecting into the sleeve 14. The driving and driven clutch members 34 and 36 are both cylindrical in shape and have their axes aligned with the axis of the outside knob 16. A matingly interengageable tongue 37 and groove 38 are formed on the opposed faces of the driving and driven clutch members 34 and 36, respectively.
The slide 35 carrying the driving clutch member 34 is slidably mounted within a sleeve 39 extending through the interior of the outside knob 16 in coaxial relationship thereto. The slide 35 has one or more projections 40 on its circumference which are slidably received in respective guide slots 41 formed in the sleeve 39 in its axial direction. The slide 35 is thus constrained to linear back-and-forth travel along the axis of the outside knob 16 relative to the same and is of course rotatable simultaneously therewith.
A cylinder lock assembly 42 of the well known construction is rigidly accommodated within the sleeve 39. The cylinder lock assembly 42 includes the so-called plug or cylindrical rotor 43 which is rotable in both directions relative to the outside knob 16 by the aforementioned key 33. A helical compression spring 44 is mounted between the cylinder lock assembly 42 and the slide 35 to bias the latter, and therefore the driving member 34 of the second clutch 32, toward the driven clutch member 36.
The slide 35 and the rotor 43 of the cylinder lock assembly 42 are operatively interconnected by cam means generally labeled 45.
As illustrated in greater detail in FIG. 4, the cam means 45 comprises a first cam element 46 fixedly mounted on the inside end of the rotor 43 for simultaneous rotation therewith, and a second cam element 47 fixedly mounted on the slide 35 in opposed relationship to the first cam element. The first and second cam elements 46 and 47 have mating jaw-like portions such that the two cam elements are normally closely interengageable as illustrated in FIGS. 1 and 2. When the rotor 43 of the cylinder lock assembly 42 is rotated in a predetermined direction by the key 33, the cam elements 46 and 47 gradually disengage or release each other, in such a manner that the second cam element is moved away from the first cam element by the compression spring 44. The cam elements do not completely disengage each other even when the second cam element is a pre-determined maximum distance away from the first cam element. The second cam element can therefore be pulled back into close re-engagement with the first cam element against the bias of the compression spring 44 when the rotor 43 is succeedingly rotated in the opposite direction by the key 33.
In operation, if the inside knob 15 is turned while the push button 20 is not depressed, as illustrated in FIG. 1, the actuator rod 19 will rotate simultaneously thereby causing, for example, the unshown latch bolt to withdraw into the door 12 in the conventional manner. The door is now openable. The door is also openable if the outside knob 16 is turned while the push button 20 is not depressed, because then the actuator rod 19 rotates via the engaged first clutch 24.
In FIG. 2 the push button 20 is shown depressed against the bias of the compression spring 30 and retained in the depressed position by the pin 23 entering the L-shaped groove 22 therein. Upon depression of the push button 20, the actuator rod 19 travels toward the outside of the door until the driven member 26 of the first clutch 24 is completely disengaged from the driving member 25. With the outside knob thus declutched, the door is openable only by the inside knob 15, because then the mere turn of the outside knob 16 results in the idling of the driving clutch member 25 around the actuator rod 19.
In order to open the door 12 from the outside while the push button 20 is held depressed, the key 33 must be inserted into the keyhole of the cylinder lock assembly 42 and turned in the predetermined direction, as illustrated in FIG. 3. The resulting rotation of the rotor 43 relative to the outside knob 16 causes the gradual disengagement of the first and second cam elements 46 and 47 of the cam means 45. With the second cam element 47 thus gradually released from the first cam element 46, the slide 35 with the driving member 34 of the second clutch 32 travels toward the inside of the door by the pressure of the compression spring 44 until the tongue 37 on the driving clutch member 34 becomes engaged in the groove 38 on the driven clutch member 36.
If now the outside knob 16 is turned, the actuator rod 19 will rotate via the slide 35 and the engaged second clutch 32, so that the door is openable. The key 33 may then be turned in the opposite direction and pulled out of the key-hole. Since the first cam element 46 rotates simultaneously with the rotor 43 in this opposite direction, the second cam element 47 is pulled back into close re-engagement with the first cam element against the bias of the compression spring 44, as mentioned previously. The slide 35 simultaneously travels back to the position shown in FIG. 2 thereby disengaging the driving member 34 of the second clutch 32 from its driven member 36.
The driving and driven members 34 and 36 of the second clutch 32 may not properly interengage when the former is first brought into contact with the latter upon gradual disengagement of the cam means 45. However, since the opposed surfaces of the driving and driven clutch members 34 and 36 and then resiliently urged against each other by the compression spring 44, the tongue 37 on the driving clutch member is bound to become properly engaged in the groove 38 on the driven clutch member as the outside knob 16 is turned succeedingly. The door can therefore be smoothly and positively unlocked without any undue stress exerted on the second clutch 32.
Although the improved door locking device according to the invention has been shown and described hereinbefore in very specific aspects thereof, it is to be understood that the invention itself is not to be restricted by the exact showing of the drawings or the description thereof. Various modifications may well occur to those skilled in the art on the basis of this disclosure, without necessarily departing from the scope of the invention as defined by the following claims.
This invention relates generally to locks and more specifically to a door locking device. Still more specifically, the invention deals with a door locking device of the type comprising a pair of knobs rotatably supported on the inside and the outside, respectively, of a door, and an actuator rod which is normally rotatable by both knobs to cause, for example, a latch bolt to be withdrawn into the door. The inside knob has a push button which is depressible to disengage the outside knob from the actuator rod and hence to render the door un-openable from the outside unless a key is manipulated in a lock assembly built into the outside knob.
Some prior art door locking devices of the type under consideration have a drawback in common with regard to the means for permitting the door to be opened from the outside by use of a key while a push button or the like on the inside knob is held depressed or otherwise actuated. A typical example of such prior art devices includes what may be termed an unlocking cylinder mounted within a sleeve which is integral with the outside knob. When the key is turned in the outside knob, the unlocking cylinder rotates and travels toward the inside of the door as guided by helical grooves on the internal surface of the sleeve. The unlocking cylinder has a groove which is intended to engage, at the end of the inward stroke of the cylinder, a tongue on a member rotatable with an actuator rod so that the door may be opened by the turn of the outside knob.
The door can of course be unlocked if the groove correctly engages the tongue at the end of the inward stroke of the unlocking cylinder. However, in event the angular position of the rotatable unlocking cylinder at the end of its inward stroke is not exactly adjusted to that of the tongued member, the door is not openable by the succeeding turn of the outside knob. The key must then be manipulated again after rotating the outside knob through a suitable angle in order that correct interengagement may result between tongue and groove. Not only is this unlocking procedure troublesome, but the repetition of the procedure can cause premature wear or damage to the contacting surfaces of the unlocking cylinder and tongued member. The door may eventually become unlockable from the outside.
SUMMARY OF THE INVENTION
It is among the objects of this invention to provide an improved door locking device of such construction that the door can be smoothly and positively unlocked from the outside by a key, practically without any undue stress exerted on the working parts of the unlocking mechanism.
With the above and other objects in view, this invention provides a door locking device including an actuator rod which extends between inside and outside knobs and which is normally rotatable by both knobs to actuate the usual latch bolt of the like so that the door may be opened from either the inside or the outside. The device further comprises a first clutch which normally connects the outside knob to the actuator rod and which disengages upon depression of a push button on the inside knob, and a second clutch which engages to connect the outside knob to the actuator rod only when a lock assembly built into the outside knob is operated by a key while the first clutch is held disengaged.
The first clutch comprises a driving member fixedly supported by the outside knob for simultaneous rotation therewith, and a driven member fixedly mounted on one end of the actuator rod which projects into the outside knob by rotatably and longitudinally movably extending through the driving member. Upon depression of the push button the actuator rod travels toward the outside of the door so that the driven member of the first clutch moves out of engagement with the driving member.
The second clutch includes a driven member located at the same end of the actuator rod as the driven member of the first clutch. The driving member of the second clutch is fixedly mounted on a slide within the outside knob which is constrained to linear movement toward and away from the driven clutch member. For moving the driving member of the second clutch into and out of engagement with the driven clutch member, cam means is provided between the slide and the lock assembly. The lock assembly may take the form of the well known cylinder lock including a cylindrical rotor which rotates in both directions with the key.
Thus, when the key is manipulated in the lock assembly to rotate the rotor in a predetermined direction while the push button is held depressed, the cam means operates to permit the slide to move, without rotation, toward the driven member of the second clutch by the pressure of spring means. The driving member of the second clutch carried by the slide thus moves into correct engagement with its driven member. The door is now openable from the outside, because then the rotation of the outside knob can be transmitted to the actuator rod via the slide and the second clutch.
The features which are believed to be novel and characteristic of this invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and mode of operation, together with the further objects and advantages thereof, will become apparent from the following description of a preferred embodiment, which is to be read in connection with the accompanying drawings in which like reference characters refer to like parts throughout the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates, partly in perspective and partly in axial section, a door locking device embodying this invention, the view showing a first clutch engaged and a second clutch disengaged, so that the door is openable from either the inside or the outside by the turn of the knobs;
FIG. 2 is a view similar to FIG. 1 but showing both first and second clutches disengaged, so that the door is un-openable from the outside unless a key is used;
FIG. 3 is a fragmentary view illustrating, also partly in perspective and partly in axial section, the door locking device in which the second clutch is shown engaged by the manipulation of the key; and
FIG. 4 is a perspective detail view of cam means used in the door locking device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With particular reference to FIG. 1, the illustrated door locking device includes a pair of generally circular mounting members 10 and 11 fixedly supported on the inside and the outside, respectively, of a door 12 in axial alignment. The mounting members 10 and 11 have axial openings therethrough for rotatably receiving sleeves 13 and 14 which are integral parts of knobs 15 and 16, respectively. It will therefore be seen that these knobs 15 and 16 are rotatably supported by the respective mounting members 10 and 11 with their axes of rotation aligned with each other. The knob 15 is herein termed the inside knob and the knob 16 the outside knob.
A cylindrical guide 17 is closely fitted within the sleeve 13 of the inside knob 15 at its end opposite to the outside knob 16. This guide has a plurality of circumferentially spaced projections 18 which are engaged in corresponding apertures in the sleeve 13, so that the guide is immovable relative to the sleeve. An opening of rectangular cross section extends axially through the guide 17.
An actuator rod 19 of rectangular cross section, adapted to actuate in the conventional manner the usual latch bolt or the like (not shown) operatively mounted in the door 12, slidably extends through the axial opening in the guide 17. The actuator rod 19 is movable longitudinally relative to the guide 17 and hence to the inside knob 15 and is rotatable simultaneously therewith.
At one end of the actuator rod 19, seen to the left in FIG. 1, there is rotatably mounted a push button 20 in axial alignment therewith. The push button 20 includes, or doubles as, a thumbpiece 21 and projects out of the inside knob 15 both rotatably and longitudinally movably relative to the same. The push button 20 has a groove or slot 22 formed in its cylindrical portion within the inside knob 15. The groove 22 is in the shape of an L both limbs of which extend in the circumferential and axial directions, respectively, of the cylindrical portion. A pin 23 projecting radially inwardly from the inside knob 15 is slidably engaged in the L-shaped groove 22. Thus, by turning the thumbpiece 21 in a predetermined direction following the depression of the push button 20, the push button can be releasably held in the depressed position, as will be seen by referring to FIG. 2.
The reference numeral 24 generally designates a first clutch of the so-called "positive" or, more specifically, "claw" type adapted to permit the door 12 to be opened by the turn of the outside knob 16 when the push button 20 is not depressed. The first clutch 24 comprises a driving member 25 fixedly supported within the sleeve 14 of the outside knob 16, and a driven member 26 fixedly mounted on the other end of the actuator rod 19 projecting into the sleeve 14 by rotatably and longitudinally movably extending through an axial opening in the driving clutch member 25.
The driving clutch member 25 has a plurality of circumferentially spaced projections 27 which are engaged in corresponding apertures in the sleeve 14, so that the driving clutch member is immovable relative to the sleeve. The driving and driven clutch members 25 and 26 have claws or teeth 28 and 29, respectively, projecting toward each other for interengagement only when the push button 20 is not depressed.
A helical compression spring 30 is mounted between the driven clutch member 25 and a spring retainer 31 within the sleeve 14 of the outside knob 16. The actuator rod 19 is therefore biased toward the inside of the door 12 via the driven clutch member 25.
The reference numeral 32 generally designates a second clutch of what may be termed a tongue-and-groove type adapted to permit the door to be opened by the outside knob 16 and with the use of a key 33, FIG. 3, when the push button 20 is held depressed. The second clutch 32 comprises a driving member 34 fixedly mounted on a disc-shaped slide or carriage 35 within the outside knob 16, and a driven member 36 formed at the said other end of the actuator rod 19 projecting into the sleeve 14. The driving and driven clutch members 34 and 36 are both cylindrical in shape and have their axes aligned with the axis of the outside knob 16. A matingly interengageable tongue 37 and groove 38 are formed on the opposed faces of the driving and driven clutch members 34 and 36, respectively.
The slide 35 carrying the driving clutch member 34 is slidably mounted within a sleeve 39 extending through the interior of the outside knob 16 in coaxial relationship thereto. The slide 35 has one or more projections 40 on its circumference which are slidably received in respective guide slots 41 formed in the sleeve 39 in its axial direction. The slide 35 is thus constrained to linear back-and-forth travel along the axis of the outside knob 16 relative to the same and is of course rotatable simultaneously therewith.
A cylinder lock assembly 42 of the well known construction is rigidly accommodated within the sleeve 39. The cylinder lock assembly 42 includes the so-called plug or cylindrical rotor 43 which is rotable in both directions relative to the outside knob 16 by the aforementioned key 33. A helical compression spring 44 is mounted between the cylinder lock assembly 42 and the slide 35 to bias the latter, and therefore the driving member 34 of the second clutch 32, toward the driven clutch member 36.
The slide 35 and the rotor 43 of the cylinder lock assembly 42 are operatively interconnected by cam means generally labeled 45.
As illustrated in greater detail in FIG. 4, the cam means 45 comprises a first cam element 46 fixedly mounted on the inside end of the rotor 43 for simultaneous rotation therewith, and a second cam element 47 fixedly mounted on the slide 35 in opposed relationship to the first cam element. The first and second cam elements 46 and 47 have mating jaw-like portions such that the two cam elements are normally closely interengageable as illustrated in FIGS. 1 and 2. When the rotor 43 of the cylinder lock assembly 42 is rotated in a predetermined direction by the key 33, the cam elements 46 and 47 gradually disengage or release each other, in such a manner that the second cam element is moved away from the first cam element by the compression spring 44. The cam elements do not completely disengage each other even when the second cam element is a pre-determined maximum distance away from the first cam element. The second cam element can therefore be pulled back into close re-engagement with the first cam element against the bias of the compression spring 44 when the rotor 43 is succeedingly rotated in the opposite direction by the key 33.
In operation, if the inside knob 15 is turned while the push button 20 is not depressed, as illustrated in FIG. 1, the actuator rod 19 will rotate simultaneously thereby causing, for example, the unshown latch bolt to withdraw into the door 12 in the conventional manner. The door is now openable. The door is also openable if the outside knob 16 is turned while the push button 20 is not depressed, because then the actuator rod 19 rotates via the engaged first clutch 24.
In FIG. 2 the push button 20 is shown depressed against the bias of the compression spring 30 and retained in the depressed position by the pin 23 entering the L-shaped groove 22 therein. Upon depression of the push button 20, the actuator rod 19 travels toward the outside of the door until the driven member 26 of the first clutch 24 is completely disengaged from the driving member 25. With the outside knob thus declutched, the door is openable only by the inside knob 15, because then the mere turn of the outside knob 16 results in the idling of the driving clutch member 25 around the actuator rod 19.
In order to open the door 12 from the outside while the push button 20 is held depressed, the key 33 must be inserted into the keyhole of the cylinder lock assembly 42 and turned in the predetermined direction, as illustrated in FIG. 3. The resulting rotation of the rotor 43 relative to the outside knob 16 causes the gradual disengagement of the first and second cam elements 46 and 47 of the cam means 45. With the second cam element 47 thus gradually released from the first cam element 46, the slide 35 with the driving member 34 of the second clutch 32 travels toward the inside of the door by the pressure of the compression spring 44 until the tongue 37 on the driving clutch member 34 becomes engaged in the groove 38 on the driven clutch member 36.
If now the outside knob 16 is turned, the actuator rod 19 will rotate via the slide 35 and the engaged second clutch 32, so that the door is openable. The key 33 may then be turned in the opposite direction and pulled out of the key-hole. Since the first cam element 46 rotates simultaneously with the rotor 43 in this opposite direction, the second cam element 47 is pulled back into close re-engagement with the first cam element against the bias of the compression spring 44, as mentioned previously. The slide 35 simultaneously travels back to the position shown in FIG. 2 thereby disengaging the driving member 34 of the second clutch 32 from its driven member 36.
The driving and driven members 34 and 36 of the second clutch 32 may not properly interengage when the former is first brought into contact with the latter upon gradual disengagement of the cam means 45. However, since the opposed surfaces of the driving and driven clutch members 34 and 36 and then resiliently urged against each other by the compression spring 44, the tongue 37 on the driving clutch member is bound to become properly engaged in the groove 38 on the driven clutch member as the outside knob 16 is turned succeedingly. The door can therefore be smoothly and positively unlocked without any undue stress exerted on the second clutch 32.
Although the improved door locking device according to the invention has been shown and described hereinbefore in very specific aspects thereof, it is to be understood that the invention itself is not to be restricted by the exact showing of the drawings or the description thereof. Various modifications may well occur to those skilled in the art on the basis of this disclosure, without necessarily departing from the scope of the invention as defined by the following claims.