The present invention relates in general to combination locks, and more particularly to spindles for combination locks that may be easily adapted for use under various mounting conditions.
Combination locks of the multiple tumbler wheel type with which the present invention is concerned usually comprise three disk-shaped tumbler wheels having a gating or notch in their periphery and spaced side-by-side on a cylindrical tumbler post projecting inwardly of the lock housing. One of the tumblers, either the forwardmost or rearmost of the three, typically is driven by a drive pin projecting toward the tumbler from a rotatable driving cam which directly engages a stop on the tumbler or a rotary fly washer which in turn engages such a tumbler stop to provide a lost motion driving connection. The remaining tumblers are driven by an adjacent tumbler in the direction of the driving cam through a similar lost motion driving connection. The driving cam has a generally cylindrical periphery interrupted by a gating shaped to receive a fence lever nose therein at one angular position of the driving cam. The gating is structured to permit the fence carried by the fence lever to approach the tumbler wheels and enter the tumbler gatings when they are aligned with the fence. Thereupon, rotation of the driving cam through a limited arc in a selected direction effects withdrawal of the lock bolt to which the fence lever is pivoted, as a result of the fence lever nose being seated in the driving cam gate.
The driving cam is rotated to position the tumblers and retract or project the bolt by keying it on a drive spindle projecting externally of the lock casing. A mechanical dial is fixed to the external end of the spindle. A typical prior art spindle is usually threaded over a substantial portion of its length, and the driving cam is generally designed with an internally threaded bore structured to be threaded onto the spindle. Both the spindle and driving cam are provided with a spline or keyway and are disposed to be in registry with each other when the driving cam gate is oriented in a preselected relation to the dial markings to receive a spline key and lock the driving cam and spindle against relative rotation. This rotation of the mechanical dial directly rotates the driving cam to effect adjustment of the tumblers and movement of the bolt.
It has been the customary practice in the lock manufacturing industry to locate the mating splines in the spindle and driving cam so that the driving cam may be keyed to the spindle at an angular position wherein the driving cam gating is located immediately below the fence lever nose to receive the nose when the zero dial marking, or a dial marking located no more than about ten points to the left or right of zero, is aligned with the fixed index mark for the dial readings. This practice has been adhered to largely because the dialing conventions for combination locks are such that the dial is usually rotated through three full revolutions in one direction to align the first number of the combination with the fixed index mark, then two full revolutions in the opposite direction to align the second number of the combination with the index mark, then one full revolution in the first direction to align the third number of the combination with the index mark, and then returned to zero and rotated through a preselected small arc to drop the fence lever nose into the driving cam gating, thus retracting the bolt. It is only by keying the driving cam to the spindle at such an angular position that the driving cam gate is positioned to receive the fence lever nose at or near the zero dial position. Thus, prior art spindles required that the manufacturer locate the spline in the spindle at the proper angular position to provide the required angular relationship between the driving cam and dial markings so that the driving cam gate may receive the fence lever nose when the dial is positioned near zero.
This type of spindle design would generally present no particular problem for manufacturers as long as the lock device coupled to the spindle was always installed at the same angular position relative to the dial. However, in actual practice, combination locks are installed in a wide variety of angular positions, termed “hands of installation,” depending upon the particular mounting application of the lock. For example, a lock device with a bolt projecting from one end thereof may be arranged in a right hand horizontal installation or a left hand horizontal installation, wherein the bolt projects to the right or to the left, respectively (when viewing the lock device from the rear). Right and left hand horizontal installations allow the lock device to be used with right or left hand swinging doors of safes or other secured areas. In other applications, such as for sliding drawers of filing cabinets, desks, and the like, and in some safe applications, it is desirable to arrange the lock device so that the bolt projects vertically up or down.
Each of these different hands of installation requires that either the spindle or the driving cam spline be located at a different angular position in order to preserve the relationship between the driving cam gate and the zero mark on the dial whereby the fence lever nose can drop into the driving cam gate at a dial position wherein a dial marking near the zero mark is aligned with the fixed index mark located vertically above the center axis of the dial. In order to accommodate the various installation conditions, the commercial locksmith must carry in his stock of repair parts spindles or driving cams keyed for each of the different hands of installation. The general practice for some locksmiths has been to stock spindles splined for each of the four principal hands of installation, including right horizontal, left horizontal, vertical up, and vertical down. However, having to stock a wide variety of spindles is not only inconvenient, but it also presents a substantial financial hardship to the locksmith.
In addition, the length of the spindles used in combination locks is not standardized and depends upon, for example, the separation distance between the dial on one side of the mounting surface and the lock on an opposing side of the mounting surface. For example, in some lock assemblies the required length of the spindle may be about two inches, while in other assemblies it may be about four inches. This factor also increases the variety and quantity of replacement parts which a locksmith must stock and carry in order to be adequately prepared for the variety of replacement possibilities which he may encounter. In some situations the locksmith may cut off a portion of the spindle in order to obtain a spindle having a desired length. However, under such circumstances, the portion of the spindle where the cut is made has to be “deburred” such that all sharp, jagged edges or other abnormalities resulting from the cut are eliminated. If this step is not taken, the spindle may, for example, tear or otherwise damage the cam in the lock device.
Therefore, there is a need for a spindle that may be easily adapted for use in conjunction with various separation distances between the dial and lock device as well as at various hands of installation.
The present invention solves the foregoing problems by providing a lock assembly comprising a mechanical dial, a lock device, and a spindle having a spindle base and an elongate spindle shaft extending from the spindle base, the spindle shaft comprising a plurality of spindle segments having four sides and separated by a plurality of spaced apart grooves, wherein each of the spindle segments includes a chamfered leading edge. The mechanical dial includes a first side, a second side, and a coupling bushing having a bushing aperture on the first side of the mechanical dial. The lock device includes a first side, a second side, and a cam exposed through an aperture in the first side of the lock device. The spindle base is insertable into the bushing aperture in the coupling bushing and the spindle shaft is insertable into a cam aperture in the cam in order to operatively couple the mechanical dial to the lock device.
The present invention also provides a method of mounting a lock assembly on a mounting surface comprising positioning a mechanical dial on a first side of the mounting surface, positioning a lock device on a second side of the mounting surface, determining a distance between the first and second sides of the mounting surface, providing a spindle including a plurality of spindle segments having four sides and separated by a plurality of spaced apart grooves, and cutting the spindle at a selected one of the spaced apart grooves based upon the determined distance between the first and second sides of the mounting surface.
Therefore, one object of the present invention is the provision of a novel dial and spindle construction for combination lock assemblies which may be readily conditioned by locksmiths in the field to adapt the unit for use in lock devices having a wide variety of hands of installation.
Another object of the present invention is the provision of a novel spindle for combination lock assemblies wherein the axial length of the spindle may be easily and quickly altered such that persons in the field can readily assemble the spindle with mechanical dials and lock devices mounted at various separation distances.
Another object of the present invention is the provision of a novel spindle for combination lock assemblies that does not require the use of a spline key to couple the spindle to the driving cam.
Other objects, advantages and capabilities of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings illustrating one embodiment of the invention.
Dial portion 25 is supported for rotation within the forwardly opening cylindrical well of dial ring 24 defined by shield 24A, and is likewise supported for axial movement inwardly and outwardly with respect to dial ring 24 by means of drive spindle 27 coupled at proximal end 28A to dial portion 25 and at distal end 28B to lock device 20. As illustrated in
As further illustrated in
Lock device 20 is provided with bolt 40 adapted to slide in a suitable guideway formed in one end wall of the lock device 20. Bolt 40 may be operated by means of fence lever 41 which may be pivotally attached to bolt 40 by means of a screw 42 or other fastener. Fence lever 41 may be provided with a laterally projecting bar, commonly referred to as a fence, which typically projects along an axis parallel to the axis of drive spindle 27 and overlies the peripheries of all of the tumbler wheels 35-37. The fence may be adapted to be received in the peripheral gates of tumbler wheels 35-37 when the tumbler gates are disposed in registry with each other at a chosen angular position upon operation of dial knob 26 to the proper opening combination of the lock. Thereafter, the resulting downward rotation of fence lever 41 will cause bolt 40 to withdraw from its projected or locking position.
Although the above discussion focused on the exemplary lock assembly 10, those skilled in the art will appreciate that spindle 27 may be used in conjunction with various other lock assemblies without departing from the intended scope of the present invention.
Turning now to
In one embodiment, spindle 27 may be formed from a metal. However, those skilled in the art will appreciate that spindle 27 may be formed from any suitable material, including plastics and the like. In addition, spindle 27 may be manufactured with any suitable means such as by casting.
In one embodiment of spindle 27, the width W of each side 66 of spindle segments 60 is approximately 6 mm. However, spindle segments 60 with sides 66 having numerous other widths W are also contemplated. Furthermore, spindle segments 60 with sides 66 having widths W that are not all substantially equal, and thus form cross-sectional shapes other than a square, are also within the intended scope of the present invention. For example, in other embodiments, spindle segments 60 may include a first pair of opposing sides having a first width and a second pair of opposing sides having a second width, thus forming a spindle segment having a generally rectangular cross-sectional shape. In yet other embodiments, the angle A formed between adjacent sides 66 of spindle segments 60 may be greater or less than 90 degrees, thus forming, for example, a parallelogram. Workers skilled in the art will appreciate that spindle segments 60 may take on numerous other cross-sectional shapes without departing from the intended scope of the present invention.
Up to this point, spindle 27 has been described as including spindle segments 60 with four sides 66. However, other embodiments of a spindle segment in accordance with the present invention may include a number of sides greater or less than four. For example, one alternative spindle design may include spindle segments having three sides and that form a generally triangular cross-sectional shape. In another alternative spindle design, the spindle segments may have five sides that form a generally pentagonal cross-sectional shape.
Threaded aperture 69 in base 50 is structured to receive a fastener such as, for example, a screw or the like. In other embodiments aperture 69 is not threaded, and the fastener is secured within the aperture via other means including, but not limited to, a press-fit type connection or an adhesive.
Chamfered edges 64 of spindle segments 60 may serve as a guide for the locksmith and assist the locksmith when trying to align spindle shaft 52 with washer aperture 110. The presence of chamfered edges 64 instead of sharp, un-chamfered edges also reduces the chances of damaging cam 32 when pushing spindle shaft 52 into the cam. Furthermore, chamfered edges 64 may also provide feedback for the locksmith by providing an audible “snap” as they are pushed through washer aperture 110.
As stated previously, one common issue for a locksmith or other individual mounting a lock assembly is that the required length of spindles varies depending upon numerous factors related to mounting conditions. For example, with respect to lock assembly 10, the separation distance between mechanical dial 22 and lock device 20 may not always be substantially the same. As a result, the axial length of the spindle spanning between the dial and lock may be too long to assemble the lock assembly such that distal end 28B of spindle 27 is contained within the interior of lock device 20. In order to address this problem, spindle 27 of the present invention has an axial length that may be shortened so as to be compatible with mechanical dials and lock devices that are mounted at various separation distances.
Once again, although spindle 27 is illustrated with eight spindle segments 60, one skilled in the art will appreciate that spindles having any number of spindle segments are contemplated and within the intended scope of the present invention. Furthermore, the axial length L of each spindle segment 60 may vary in other embodiments such that grooves 62 are spaced closer together or farther apart. Any change in the number of spindle segments or the axial length of each segment would require formulating a new spindle size table (similar to the one shown in
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.