US2917337A - Lock spindle structure - Google Patents

Description

Dec. 15, 1959 E. L. SCHLAGE 2,917,337

LOCK SPINDLE STRUCTURE Filed Oct. 15, 1956 2 sheets sheet 1 INVENTOR. ERNEST L. SCHLAGE BY 72% m KWUJ A T TORNEYS Dec. 15, 1959 1.. SCHLAGE 2,917,337

LOCK SPINDLE STRUCTURE I Filed Oct. 15, 1956 2 Sheets-Sheet 2 INVENTOR. ERNEST L. SCHLAGE BY 7 M M Qzy/m A T TORNE rs LOCK SPINDLE STRUCTURE Ernest L. Schlage, Burlingame, Calif., assignor to Schlage Lock Company, a corporation Application October 15, 1956, Serial No. 615,887

3 Claims. (Cl. 292-3365) This invention relates to door locks and more particularly to an improved construction of the outer knob spindle and its associated rollback member.

In the type of door lock here illustrated there is provided an inner and an outer independently operable knob spindle, and in the conventional case each spindle carries a rollback member which engages a retractor. When either spindle is rotated in either direction its rollback member imparts movement to the retractor, and, as the retractor is connected to the latch bolt, the latter moves in unison and is retracted with relation to the strike plate in the door frame. A pair of compression springs oppose retracting movement of the retractor and these springs serve two functions, first, that of returning the retractor to the outer or projected position of the latch bolt, and second, that of returning the spindles and rollbacks to a normal, centered position. These springs then maintain the retractor in engagement with the above two functions.

In locks of this type it is also customary to provide a means for locking the outside knob spindle against rotation so as to prevent operating the latch from the outside. In some cases this is done by providing a manually actuatable dog that dogs the outside knob spindle to the. lock housing, and which dog is held in dogged position by a latch engaging the retractor. In such a case retraction of the retractor in an amount in the order of /8" releases the latch and the dog is spring urged to an inoperative position releasing the outer knob spindle.

It has been found that there are certain difficulties inherent in the operation of the conventional type of lock above described. Since the knob spindles are mounted for rotation in cylindrical bearings some clearance must be provided for free rotation thereof, and over a period of time this clearance may increase due to wear. This allows the outer knob spindle to be tilted slightly relative to its normal axis of rotation. It has been demonstratedthat administering a sharp blow or impact to the outer knob spindle, even when the same is locked against rotation, will cause a shock to be transmitted through the outer spindle rollback to the retractor with which itis in engagement, thereby causing retractivemovement of the retractor, and correspondingly, of the latchbolt. Eventhough the'outer knob spindle is only slightly tilted bysuch a sharp blow, movement of the retractor by such means may be magnified many times. Hence, it has been found possible to transmit a sufiicient, shock to the retractor. to drive it rearwardly a sutficient distance to retract the latchbolt from the strike plate and thereby unlock. the door.

In locks of the type wherein the locking dog is latched totheretractor a sharp blow administered to the outer knobisalmost always sufficient to force theretractor backfarenough to unlatch said dog and thereby unlock theoutenknob. In either case, it has been found possible for.anunauthorized-person to obtain entry by. the above ice means through a door provided with a conventional lock of the type described.

It is therefore a primary object of this invention to. overcome the disadvantages of conventional locks by prohibiting this type of unauthorized entry.

Another object of this invention is the provision of a flexible juncture between an outer knob spindle for a door lock and its associated rollback element.

It is still another object of this invention to provide means for connecting a rollback element to an outer knob spindle for a door lock, which means permits tilting between said element and said spindle.

Other objects and advantages will become apparent from the following description taken in connection with,

the accompanying drawings, in which:

Fig. 1 is a horizontal, longitudinal sectional view of a door lock constructed in accordance with the preferred form of this invention, and showing the main parts of the lock mechanism;

Fig. 2 is a semi-diagrammatic view showing how a blow imparted to a conventional lock knob may be transmitted to the retractor;

Fig. 3 is a cross-sectional view taken generally along line 33 of Fig. 1;

Fig. 4 is a view similar to Fig. 2, but reversed, and

showing the preferred construction of Fig. 1;

Fig. 5 is a sectional view taken along :line 5-5 of Fig.

4, showing the preferred spindle and rollback connection;

Fig. 6 is an exploded perspective view of the main elements of the preferred form of Fig. 1; and

Figs. 7, 8, and 9 are side elevational views of modified,

forms of the outer spindle and rollback connection.

In detail, referring to Fig. L'the spindle construction.

of this invention is illustrated in combination with a door lock of the cylindrical type. Such a door lock conventionally comprises a latch unit, generally designated 1,

having a latch bolt 2 movable between a projected position (as shown in Fig. l) and a retracted position. Latch bolt 2 is normally provided with a spring (not shown) for urging it to the projected position and a latch bar 3' which extends rearwardly into a cylindrical lock housing;

4. A retractor, generally designated 5, is slidably mounted between a pair of thrust plates 6, 7 (Fig. l) in housing 4 and has a pair of jaws 8 engageable with a pair of lugs 9 (Figs. 1, 3) on latch bar 3. Retractor 5 is slidable between an outer position in which the latch bolt 2 is projected to an inner position in which said retractor withdraws bolt 2 to the retracted position. A pair of helical compression springs 10 act to urge retractor 5 to said outer position. It will be noted that housing 4 is made in two parts, and that the inner part is provided with spring retainers 11 (Figs. 1, 3) against which one of the ends of springs 10 abuts.

The lock of Fig. 1 is also provided with inner and outer knob spindles 12, 13, respectively. Said knob spindles are tubular in shape and are supported in bearings 14, 15 for independent rotation about a common axis extending through retractor 5. Spindles 12, 13 are rotated in the usual manner by means of knobs 16, 17 securedto the outer ends thereof. It is also conventional to provide an escutcheon plate 18, 19 surrounding each bearing 14, 15 and adapted to be in engagement with opposed faces of the door in which the lock is mounted for covering the hole bored to receive lock housing 4.

A portion of inner knob spindle 12 extends into lock housing 4 and is formed with a rollback member 20 which is in engagement with an intermediate thrust member 21 formed integrally with retractor 5 (Figs. 1, 3, 4). By this means rotation of inner knob 16 in either direction imparts retracting movement to retractor 5 in the usual manner. to slide said retractor to its inner position against theforce of springs 10,. It will be seen that once inner knob 16 is released from its rotated position springs 10 urge retractor 5 to its outer position and at the same time thrust member 21 rotates spindle 12 through rollback member 20 back to its normal, center position.. .Since springs urge retractor 5 toward its outer position at all times, thrust member 21 is at all times in engagement with rollback member 20 and therefore spindle 12 is always centered at rest.

In previous lock construction it has been the practice to form the outside knob spindle 13 with a similar rollback member 22 (Fig. 2). This rollback 22 has similarly been held in engagement with retractor 5 at all times for the purposes of centering outside knob 17, as previously described with respect to inner knob 16. This prior construction has, however, resulted in a serious deficiency in the lock structure. It has been found, for instance, that a certain amount of clearance or play must be maintained between knob spindle 13 and its associated bearing 15 in order that knob 17 may be easily operated. This clearance may, of course, be increased due to wear between the spindle and hearing.

In tests performed on the conventional structure indicated in Fig. 2 it has been noted that a blow imparted to outer knob 17 in the direction of arrow 23 causes knob spindle 13 to be tilted from its normal axis of rotation at 24 to the position represented by dot-dash line 26 and a slightly angularly disposed axis 25 (Fig. 2). This tilting of knob 17 and spindle 13 cause the conventional outer rollback member 22 to drive retractor 5 in the direction of arrow 27 toward its inner position. Even though the tilting of knob 17 by a sharp blow results in only a slight movement of the rollback 22 the magnitude of the shock wave transmitted thereby to retractor 5 may be such as to drive said retractor far enough toward its inner position (dot-dash line 28) to retract latch bolt 2 clear of the strike plate in the door frame. In such an instance it is seen that with the conventional structure of Fig. 2 the door may be opened by an unauthorized person, even though knob 17 may be locked against rotation, by imparting a sharp blow to said knob.

Furthermore, it is not uncommon practice to provide means for locking the outside knob against rotation such as is illustrated in Fig. 1. Such locking mechanism may comprise a dog 31 which is adapted to enter a slot 32 formed in the outer spindle 13. Dog 31 is formed at the inner end of a bar 33 which extends longitudinally through the inner spindle 12 and is provided with a pushbutton 34 on its outer end operable from the exterior of knob 16. Intermediate its ends bar 33 is provided with a latch 35 adjacent a slide plate 36 of the retractor 5. The bar 33 is normally maintained in the position shown in Fig. 1, with pushbutton 34 extending outwardly of in- Y ner knob 16, by means of a spring 29. However, if the button 34 is depressed, dog 31 enters a slot 44 formed in the housing 4 as well as slot 32 in outer spindle 13, and the dog will be retained in this position as latch 35 engages and is held by the inner face of sideplate 36. When dog 31 is held by latch 35 in this inner position, it prevents rotation of outer spindle 13 by dogging together slots 32 and 44 formed in said outer spindle and the stationary housing 4, respectively.

It will be noted, however, that bar 33 and dog 31 may be returned to the inoperative position-shown in Fig. l by spring 29 upon retracting retractor 5 sufliciently to disengage plate 36 from latch 35. This amount of retraction of retractor 5 need only be of the order of A3" which, it has been found, can be easily transmitted by rapping the outer knob 17 of the construction shown in Fig. 2. It is because of these difiiculties with conventional construction that the device of this invention is provided.

Generally the device of this invention comprises a separate rollback element which is flexibly connected to the outside knob spindle 13 so that the force of a blow struck on the outside knob 17 will not be transmitted to the rehowever,

tractor 5. In the preferred form shown in Figs. 1, 3, 4, 5, 6, the rollback element 37 is formed to the conventional arcuate configuration with a pair of cars 38 at opposite sides thereof in engagement with the thrust members 21 of retractor 5. Rollback 37 is provided with an arcuate foot member or flange 39 which extends around the outer periphery of spindle 13. Flange 39 is supported between a portion of housing 4 and thrust plate 7 (Fig. 5) so that rollback element 37 is supported for rotation about the axis 24 of rotation of outer spindle 13. A radial projection 40 on flange 39 is loosely received in an aperture 41 in outer spindle 13 for the purpose of transmitting rotational movement of spindle 13 to rollback element 37.

It will be noted, with reference to Fig. 4, that imparting a blow to outer knob 17 in the direction of arrow 42 may tilt knob 17 and spindle 13 to the dot-dash position 43 but this movement will not be transmitted to the retractor 5 in the manner previously described with reference to Fig. 2. The loose fit of projection 40 in aperture 41, which is the only connection between rollback element 37 and outer spindle 13, acts as a flexible juncture between the two which takes up the tilting action of knob 17 without transmitting the same to the retractor 5. Hence, the previously described unauthorized opening of the lock is prohibited by the device of this invention.

When outer knob 17 is in the unlocked condition, normal rotation thereof will be transmitted from outer spindle 13 through the projection and aperture connection 40, 41 to rollback element 37 which will then move the retractor 5 rearwardly in the normal manner. In eflect, the device illustrated in Figs; 1, 3-6 isolates retractor 5 from any tilting movement of outer spindle 13 in a direction of retraction of said retractor.

Figs. 7 and 8 illustrate modified forms of a flexible connection between rollback elements 45, 46 and outside knob spindles 47, 48, respectively. In Fig. 7 rollback element 45 is formed similar to rollback element 37 except that the former is provided with a dovetail 49 which is received in a complementary recess 50 formed in the side of outside tubular spindle 47 adjacent the latch unit.

In Fig. 8 it will be seen that spindle 48 is formed with an axially projecting dovetail 51 received in a recess 52 provided in a rollback element 46.

In the modifications of Figs. 7 and 8 rollback elements 45, 46 are supported for rotation with outside spindles 47, 48 as if the former were extensions of the latter. Therefore, rotation of knob spindles 47, 48 in their bearings in thrust plate 7 causes retraction of retractor 5 and thereby latchbolt 2 in the normal manner. The dovetail connections 49, 50 and 51, 52 between said outer spindles and said rollback elements permits the tilting of spindles 47, 48 with respect to rollback elements 45, 46, respectively, in a direction of movement of the retractor. Hence a blow imparted to the outside knob, as previously described, will be absorbed in the flexible connections 49, 50 and 51, 52 and will not be transmitted to rollback elements 45, 46 or the retractor.

Another modification shown in Fig. 9 provides an outside knob spindle 53 supported in the normal manner and provided with a rollback element 54 formed similar to the previously described rollback element 37. Element 54 may be formed as an extension of tubular spindle 53 but a pair of elongated slots 55 are provided extending axially from the rollback element 54 back through the wall of said spindle. These slots may terminate in enlargements 56 between which a hole 57 may be provided for the purpose of weakening the juncture 58 between rollback element 54 and spindle 53.

Such a weakened juncture 58 is sufi'icient to transmit rotational movement of the knob spindle 53 to rollback element 54 for retracting the retractor and latchbolt in the normal manner. The juncture 58, being the only connection between spindle 53 and rollback element 54, is,

sufiiciently flexible to permit relative tilting between said spindle and said rollback element. Hence, unauthorized transmission of a force to the retractor, as explained with respect to Fig. 2, is prohibited by the device of Fig. 9 by absorbing the tilting of knob spindle 53 in the direction of movement of the retractor in the flexible connection 58.

It will be noted that in all the modifications the retractor springs do not tilt the outer spindle rollback element when in the normal centered position because the force of said springs is taken on the integral inner rollback 20. Springs 10 still act to center the outer knob 17 but do not otherwise affect the relationship of the parts as shown.

Although the invention has been described as illustrated in detail it is obvious that various other modifications could be resorted to without parting from the spirit and scope of the following claims.

I claim:

1. In a door lock of the character described having a slidably mounted, spring projected latchbolt retractor and a spindle supported for rotation about an axis extending through said retractor and normal to the direction of sliding movement thereof, the improvement, comprising: a rollback element, means supporting said element for rotation about said axis and in engagement with said retractor at two spaced points around the periphery of a circle concentric with said axis for retracting said retractor upon rotation of said element, and interengaging means carried by said spindle and said element spaced from said retractor and including a projection on one of said spindles and said element and an opening on the other receiving said projection connecting said spindle and said element for rotational and axial movement together and permitting independent tilting movement of said spindle relative to said axis and said element.

2. In a door lock of the character described having a slidably mounted, spring projected latchbolt retractor and a spindle supported for rotation about an axis extending through said retractor and normal to the direction of sliding movement thereof, the improvement, comprising: a rollback element, means supporting said element for rotation about said axis and in engagement with said re tractor at two spaced points around the periphery of a circle concentric with said axis for retracting said retractor upon rotation of said element, and interengaging means carried by said spindle and said element spaced from said retractor and including a projection on one of said spindles and said element and an opening on the other receiving said projection connecting said spindle and said element for rotational and axial movement together and permitting independent tilting movement of said spindle relative to said axis and said element, said supporting means including a radial flange on said element, and said interengaging means being a radial opening provided in said spindle and a radial projection on said element received in said opening.

3. In a door lock of the character described having a slidably mounted, spring projected latchbolt retractor and a spindle supported for rotation about an axis extending through said retractor and normal to the direction of sliding movement thereof, the improvement, comprising: a rollback element, means supporting said element for rotation about said axis and in engagement with said retractor at two spaced points around the periphery of a circle concentric with said axis for retracting said retractor upon rotation of said element, and interengaging means carried by said spindle and said element spaced from said retractor and including a projection on one of said spindles and said element and an opening on the other receiving said projection connecting said spindle and said element for rotational and axial movement together and permitting independent tilting movement of said spindle relative to said axis and said element, said interengaging means being a dovetail connection extending parallel with said axis.

References Cited in the file of this patent UNITED STATES PATENTS 1,639,434 Morgan Aug. 16, 1927 1,829,815 Schlage Nov. 3, 1931 1,895,894 Moore Jan. 31, 1933 1,970,758 Lyons et a1. Aug. 21, 1934 2,297,077 Schlage Sept. 29, 1942 2,427,436 Beems et a1. Sept. 16, 1947 2,547,256 Cerf Apr. 3, 1951 2,611,635 Cerf Sept. 23, 1952

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