CA2154328A1 - High security lock system including tapered keyway - Google Patents

Abstract

A high security lock includes a lock cylinder and a plug within the cylinder. The plug is rotatable about an imaginary axis and defines a keyway having two opposing keyway sides extending longitudinally within the plug. The keyway sides taper with respect to an imaginary plane dividing the keyway. One or more paracentric keyway ribs protrude from the keyway sides. The apparatus further includes a high security key comprising a bow region, a key guide region, and a key blade which has two opposing key sides which taper with respect to an imaginary line dividing the key blade. The key blade has key grooves corresponding to the keyway ribs.

Description

21~328 ~IIG}~ 8~C~JRITY LOC~ SYSTE~ INCLUDING TAPEI~.ED R~Y~AY
BACXGROUND OF THE INVENTION
Field Of The Invention ~ his invention relates to a lcck construction providing i~proved security features. More particularly, this invention relates to a high security cylinder lock construction including a tapered keyway and complimentary key blank.
Bac~round of the Invention It is often desirable to afford increased security in lock and padlock mechanisms. Additional security and control can be obtained by decreasing the number of key blanks which can ~e utilized to engage a particular loc~ mechanism. Control over key blanks may be achieved by the manufacturer restricting proprietary key blanks. Additional protection is available if key blanks cannot be modified or counterfeited to enter proprietary key slots. For example, key blank and cylinder mechanisms have been suggested which may utilize a particular cross-sectional configuration, curvature, ridge or indentation to restrict the number o~ key blanks that can fit into the keyway.
However, most security features in lock mechanisms exhibit complex configurations and adaptations which are expensive to manufacture, and comprise additional moving parts which can cause reliability problems. One method of increasing the sec~rity of a lock r?ch~nism i5 to increase the intricacy of the key and keyway configurations, for instance by adding the number of blade portions and corresponding keyway portions. For example, U.S.
Patent No. 4,787,225 teaches a dual blade key blank. The dual 21~3~

blades are connected by a brid~ing portion, which in turn is connected to a guide region. The keyway is similarly shaped for receiving the dual key blank. As result, a standard key blank cannot be received by the lock mechanism, thus reducing the possibility of undesired access. However, the construction of this key blank is overly complex relative to a single-blade key blanX. Manufacturing a multi-bladed key and corresponding keyway structure requires additional materials, expense and time. This structure teaches away from simply designed key blade and keyway structures.
Another method of increasing the security of lock mechanisms is to use an axially slidable detent which operates to arrest the rotat$on of the lock mechanism. For example, U.S. Patent No.
4,723,427 teaches an augmented key and cylinder lock which include~ a spring-pressed detent which normally rest~ across the boundary from the plug of the loc~ mechanism to a notch in the lock mechanism housing. 8ecause the detent rests across the boundary, the plug cannot rotate relative to the housing and as a result the lock mechanism cannot be actuated. The '42~ patent teaches a key blank with an augmented portion in the region bet~een th~ bow o~ the key and key blade. This auqmented portion of the k-y blank enter~ into the notch and displaces the detent to a retracted position which allows the plug to rotate relative to the housing. 8ecause it lac~s the auqmentation necessary to displace the detent, a standard key blank cannot operate this lock mechanism. However, this device has the shortcomings of requiring additional moving parts, which decreases the overall 215~3~

reliability of the lock mechanism and increases manufacturing costs. Furthermore, such a feature is susceptible to picking because depressing the detent mechanism with an appropriate tool will disengage the detent.
It is further desirable to add additional security to lock mechanism~ by utilizing paracentric keyways to hinder picking. A
paracentric keyway is one in which the contoured ribs, also known as "wards, n project beyond the center line of the keyway.
However, paracentric keyways are able to receive keys made from many available key blanks, which enables an unauthorized person to gain access by cutting bittings into a key blank to match a given lock mechanism. Thus, the paracentric feature, by itself, does not afford sufficient protection against undesired operation of lock ~ech~isms.
In summary, known means of increasin~ the security of lock mechanlsms may have the disadvantage of increasing the overall complexity of the mechanism and increasing manufacturin~ costs and the number of parts necessary to achieve increased security.
However, owing to the pervasive use of lock mechanisms and the existence of many ways to attempt to defeat such locks, a substantial need exists for an efficiently designed economical, high security l~ck system.
S~MMARY 0~ TH~ INVENTION
Thia and other objects of the present invention are accomplished by the provision of a key blank and cylinder lock which afford increased security and restricts the number of key blanks which can be utilized to operate the lock mechanism. The 21~328 key blank and lock of the present 1nvention include a cylinder lock for selectively preventinq or allowing access to a secured object or location, a plug in the cylinder which is rotatable around an imaginary axis parallel to the cylinder's length, a keyway in the plug for receiving the key, which keyway extends along the imaginary axis and intersects the cylindrical chambers.
The keyway has first and second opposing sides forming first and second keyway side angles. The invention further comprises a key blank having an edge surface and slightly tapered first and second opposing sides forming first and second key side angles and a blade region from which bittings are cut to form a key, which fits into the keyway. The first and second key side angles correspond in magnitude to the first and second keyway sid~
angles, respectively.
One object of the invention is to afford increased security in lock mechanisms by decreasing the number of key blanks which can be utilized to engage and operate a particular loc~
mechanisn.
Another object of the invention is to provide a simply designed key blade for ease of manufacturing and increased reliability.
A furthQr ob~ect of the invention is to utilize a single blade key rather than a multiple key blade blank to reduce the cost and complexity of the lock mechanism.
Another ob~ect of the invention is to utilize a tapered key blade design which is not easily perceptible to a person attempting to gain unauthorized access to a lock mechanis~.

2 1 ~ 8 Still yet ancther object cf the invention is to utilize a tapered keyway region in the lock mechanism the upper portion of which is narrower than the typical picking tool to prevent manipulation thereby of the loc~ tumblers.
Another object of the invention is to incorporate a paracentric keyway so that the upper tapered portion of the keyway includes contoured ribs which tend to project beyond the center line of the keyway.
Another cbject of the invention is to prevent the use of a standard key blank, which has parallel edges, to be received by the keyway of this invention.
Additional objects, advantages and novel features of the invention will be set forth in the description which follo~s, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
~RIEF DESCRIPTION OF THE DRAWINGS
These and other features of the invention will now be described with reference to the drawings of a preferred embodiment which is intended to illustrate and not to limit the invention. In the accompanying drawinqs which for~ a part of the specification, the numerals and letters refer to terms and elements of the invention discussed below in the detailed description of the invention:

~15432~

FIG. 1 is a perspective view of the key of the present invention;
FIG. 2 is a cross-sectional view of the key blank of Fig. 1 taken generally along line 2-2 of FIG. 1;
FIG. 3 is a partially broken away section view of a pin-tumbler lock made in accordance with the present invention;
FIG. 4 is a front or end view of the keyway of the loc~
shown in FIG. 3;
FIG. 5 is a perspective view of the key blank of the present invention;
FIG. 6a is a front view of a key blank of one embodiment of the present invention;
FIG. 6b is a bottom view of the key blank of FIG. 6a;
FIG. 6c is a left side view of the key blank of FIG. 6a;
FIG. 6d is a right side view of the key blank of FIG. 6a;
FIG. 6e is a top view of the key blank of FIG. 6a; and FIG. 6f i~ a rear view of the key blank of FIG. 6a.
FIG. 7a is a front view of a key blank of another embodiment of the present invention;
FIG. 7b i5 a bottom view of the key blank of FIG. 7a;
FIG. 7c i5 a left side view of the key blank of FIG. 7a;
FIG. 7d is a right side view of the key blank of FIG. 7a;
FIG. 7e i~ a top view of the key blank of FIG. 7a; and FIG. 7f i5 a rear view of the key blank of FIG. 7a.

2 1 ~ 8 DE~AI~E~ DESCRIPTION OF THE I~vENTION
OVERVIEW OF INVENTION
Referring now to the drawings, FIG. 1 shows a perspective view of a key 10 made in accordance with the present invention.
~he profile of the key 10 is designed to cooperate with a complimentary shaped keyway 12, shawn in FIG. 4. In the preferred embodiment of the present invention, the sides of the key 10 and the sides of the keyway 12 are slightly tapered. The particular contour and other features of the key 10 and keyway 12 are described in greater detail hereinafter.

CY~INDER I,OCa~ MEC~IANISM
The keyway 12 shown in FIG. 1 is found in a plug 14 shown in FIG. 3, which shows a cut-away side view of a cylinder 20 having a typical tumbler lock mechanism 8. The plug 14 has a barrel section 16 and a flanqe 18. The barrel section 16 is rotatably disposed in cylinder 20 and held in place by the flange 18.
Rotation of the barrel section 16, through utilization of the key 10, unlocks the lock mechanism.
As shown in FIG. 3, a plurality of pins 22(a-f) are slidably disposed in a plurality of pin chambers 24(a-f) in plug 14.
Preferably, the pin chambers 24(a-f) lie in the same plane. A
plurality o~ drivers 26(a-f) are slidably disposed in driver chambers 28(a-g) in cylinder 20, which is contained within a lock housing such as a padlock or a door lock, and is not shown in the drawings. The pin chambers 24(a-f) intersect the keyway 12 in the upper keyway reqion 30 shown in FIG. 4 and each pin chamber 24(a-f) is aligned with one of the driver chambers 28(a-f). The 2 1 ~ 3 dri~ers 26 are biased downwardly against the pins 22 by means of springs 32.
Rey 10 i5 shown inserted in the keyway 12 of plug 14. Each of the pins 22(a-f), which may vary in length, is raised to an imaginary shear line 34 by means of bittings 36(a-f) found on the key 10. As shown in FIGS. 1 and 3, the bittings are recessed areas of the key blade which come into contact with pins 22(a-f).
The bittings interact with the pins 22, which in turn interact with the drivers 26, as is described above. ~hen the pins 22 are aligned along the imaginary shear line 34 as shown in FIG. 3, the plug 14 is free to rotate along the plug's horizontal axis within the cylinder 12 to open the lock mechanism. When any one of the pins are not aligned with the imaginary shear line 34 and rather extend past and transverse the shear line, or alternatively allow the drivers 26 to extend past the shear line, the plug 14 cannot rotate within the cylinder 20. As a result, the lock mechanism cannot operate.
REY~AY
FIG. 4 i~ a front or end view of the plug 14 and keyway 12 shown in FIG. 3. The flange 18 preferably extends radially outwardly relative to the barrel section 16 as shown in FIG. 3 of the plug and overlap~ the housing of the lock, which is not shown in the drawing~. The plug face 38 includes keyway 12 which transverses the center of the plug face 38 and extends from one edge of the plug face 38 adjacent to the flange 18 to a point approximately midway between the opposite edge of the plug face 38 and the center of the plug face. The keyway 12 is defined by 215~

generally planar left and right keyway sides 66 and 68.
Preferably, the left and right keyway sides are contoured by keyway rib portions 40 which extend longitudinally into the plug 14 from the left and right keyway sides 66 and 68. Typically, the keyway 12 has four keyway rib portions 40, however, more or fewer Xeyway rib portions 40 may be included in the keyway 12 depending, in part, on the size of the keyway 12 and corresponding key 10. As shown in FIG. 2, in one mode, the cross section of the keyway rib portion is in the shape of a 40/70/70) isosceles triangle. In alternative modes, the cross-sectional shape may vary. Furthermore, the upper keyway region 30 is connected to the keyway guide region 44 by a keyway connecting region 45.
Preferably, the keyway 12 is paracentric. A paracentric keyway is one in which the keyway rib portions 40 project beyond the imaginary keyway reference plane 42 of the keyway 12. The imaginary keyway reference plane 42 passes through the center point 39 of the keyway guide region width line 43 defined by the greatest width o~ the keyway guide region 44, the imaginary keyway reference plane 42 being perpendicular to the keyway ~uide region width line 43. The imaginary keyway reference plane 42 is shown in ~G. 4 as a vertical line. The upper keyway region 30 is narrower than the keyway guide region 44, which is located at the bottom Or the keyway 12. The paracentric feature of the keyway 12 inhibits picking because a lock pick cannot be manipulated vertically to access the upper keyway region 30 in 2 1~ ~,28 which region the pins 22 intersect the keyway 12 at the imaginary shear lin~ 34.
In onQ mode of the invention, there is an enlarged keyway rib portion 41 located between the upper keyway re~ion 30 and the keyway ~uide reqion 44, which extends across the imaginary keyway reference plane 42. The enlarged keyway rib portion 41 is particularly effective in impeding lock picking because it is located ad~acent to the keyway guide region 44, which is particularly accessible to lock picking.
REY B~AN~ AND REY
FIG. 5 shows a perspective view of a key blank 9, from which the key lO i~ ~anufactured by cutting the desired bitting profile thereon. The key blank 9 comprises two generally planar opposite left and right sides 58 and 60 having a relatively thin thickness. The key blank 9 also includes a bow region 48, a key guide region 50 and a key blade region 52. The bow region 48 is preferably wider than the cumulative width of the guide region 50 and the blade region 52. The bow region 48 provides a means to rotate the key blank 9. The guide region 50 is located at the bottom of the key blank 9. The blade region 52 is located at the top o~ th~ key ~lank 9.
FIG. 2 shows a cross-sectional view of the key blank 9 of Fig. 5 taken generally along line 2-2, thereof. The key guide region 50 is shown at the bottom of FIG. 2, and on FIGS. 1 and 5.
The key blade reqion 52 is shown at the top of FIG. 2 and on FIGS. 1 and 5. The key blank 9 includes key grooves portions 54, which extend longitudinally along the length of the key 10. Each ~ t-~ 8 Xey groove 54 corresponds to a matchinq keyway rib 40. The key blank may have an enlarged key groave portion 55 which corresponds to the enlarged keyway rib portion 41. If a particular key does not have key grooves 54 which correspond to the matching keyway ribs 40, then the key 10 will not fit within the keyway 12 and, thus, cannot actuate the lock mechanism. The key guide portion 50 is connected to the key blade portion by a connecting portion 56, shown on the left side of FIG. 2.
However, the connecting portion alternatively may be located on the right side of the key 10 of F~G. 2 to match the keyway connecting region 45, as is shswn in FIG. 7.
FIG. 1 shows a perspective view of the key 10 of the present invention. The key 10 is formed from the key blank 9, as shown in FIG. 5, by cuttinq bittings 36(a-f). The bittinqs 36(a-f) are recessed areas located on t~e blade reqion 52. The particular combinations of heights of each bitting 36(a-f), which interact with the tumbler pins 22 of a particular key, are generally unique to a particular lock. ~urthermore, the number of bittings ~ay vary in different locks and as the number of bittings increase, so does the level of security of the loc~ mechanism.
T~gR~D YEAT~RE OF REY, RBY B~N~ AND ~Y~AY
Additional security is achieved through tapering the keyway and key blank to augment the benefits of the paracentric feature of the keyway because the contoured ribs, particularly those at the narrower upper reqion of the keyway, may be desi~ned to project further beyond the vertical center line of the keyway.
As a result, it becomes very difficult for a person attempting to 21~43~

manipulate a pick vertically ~ithin the keyway to achieve their intended result. The combination of the paracentric feature and the tapered feature provides greater control over key blanks, which cannot readily be copied, as well as greater protection against picking.
The key blank 9 and key 10 have slightly tapered left and right sides 58 and 60 as is shown in FIG. 2. The angle of tapers are defined in relation to an imaginary key reference plane 47, which passes through the midpoint 49 of the lower key region width line 51 defined by the greatest width of the lower key region 50, the imaginary key reference plane 47 being perpendicular to the lower key region width line 51. The left and right key sides 58 and 60 lie in left and right imaginary key side planes 59 and 61 which converge at an imaginary point 64 above t~e key blade 52. An angle ~1 is formed by the intersection of the imaginary key reference plane 47 and the left imaginary key side plane 59. An angle ~2 is formed by the intersection of the imaginary key reference plane 47 and the right imaginary key side plane 61. Angles ~ and ~2 may range between 1 and 10.
In one embodiment, both angles ~ and ~2 are 3 in magnitude. In one mode of the invention, angles ~1 and ~2 are any equivalent angles between 1 and 10. Alternatively, angles Q1 and ~2 may differ in magnitude. For example, angle ~1 may be 1, while angle ~2 i~ 7 or angle ~1 may be 5, while angle ~2 is 4o.

~1~43~8 In any mode, the tapered feature of the left side 58 and right side 60 of the key blade 52 is generally perceptible only upon close examination of the key blade 52 and is unlikely to be perceived during normal use of the key. As can be seen in FIGS.
l and 5, in which a 3 taper is shown, the taper is very slight, rather than wedge-like. Furthermore, it is difficult to deter~ine the exact magnitude of angles ~ and ~2 without the aid of accurate measuring equipment. In one embodiment of the invention, the left and right sides 58 and 60 begin to taper above the key datum line 62 as is shown in FIG. 2. The key datum line nay be defined by the width of the key blank 9 at the upper edge 53 of the enlarged key groove portion 55. As a result of the tapered feature, the key guide region 50 is relatively wider than the key blade region 52.
A~ is shown in FIG. 4, like ~he key blank 9 and the key lO, the keyway guide region 44 is relatively wider than the upper keyway region 30. The left keyway side 66 and the right keyway side 68 of the keyway 12 lie in left and right imaginary keyway planes 67 and 69, which converge to a point above the keyway 12.
An angle e~ is formed by the intersection of the imaginary keyway reference plane 42 and the left imaginary keyway plane 67.
An angle e2 i~ defined by the intersection of the imaginary keyway re~erence plane 42 and the risht imaginary keyway plane 69. Angle~ e, and e2 may range between 1 and ~0 and preferably are ~oth 3. In one embodiment of the invention, angles e1 and e2 are equivalent. However, in an alternative mode of the invention, angles e1 and e2 may differ in magnitude. For ~154~2~

example, angle e~ may be 1, while angle ~z is 7; or angle e, ~ay be 5, while angle e2 is 4. In any mode, the tapered feature of the left keyway side 66 and right keyway side 68 of the keyway 12 is generally perceptible only upon close examination of the keyway and is unlikely to be perceived during normal use of the keyway. Furthermore, it is difficult to determine the exact magnitude of angles el and e2 without the aid of accurate measuring equipment.
The magnitude of ~ must correspond with the magnitude of e1 and the magnitude of ~z must correspond with the magnitude of ez. Otherwise, the key 10 will not fit within the keyway 12.
When a key's sides are tapered at a lesser angle than the keyway sides are tapered, then the key blank 9 cannot access the keyway 12. For example, a key 10 having left and right key sides 58 and 60 of equivalent 1 tapers, will not fit in a keyway with left and right keyway sides 66 and 68 having equivalent 5 tapers, because, in that case, the~ key lO has a wider key blade region 52 than the width of the upper keyway region 30.
Furthermore, a vast number of permutations of different keys and corresponding keyways are possible by making of varying angles the tapered opposing sides of the key and keyway. The security of the lock mechanism of this invention is enhanced because a person attempting ~o gain unauthorized access to a particular lock will be unable to determine the exact angle of taper of each particular side of the key in order to match a particular key blank with a particular lock mechanism having the tapered keyway feature.

215~3~8 The tapered sides of the key 10 and keyway 12 serve the purpose of increasing security and affording control over key blanks by limiting the type of keys which can be received by the keyway and actuate a particular lock mechanism. For example, a standard, non-paracentric key having parallel edges cannot be received by the tapered keyway of this invention. Thus, the tapered aspect of the keyway prevents standard keys from being bitted in a manner enabling access to the tapered keyway of this invention.
Moreover, a standard, non-paracentric key blank will not fit into the keyway 12 of this invention even if the standard key blade is as thin as the upper keyway region 30 of the present invention. This is because the keyway rib portions 40 of the present invention are slightly tilted relative to the respective standard key grooves due to the tapered feature of the present invention. Conversely, the key grooves 54 of the present invention match the keyway rib portions 40 of the present invention. Thus, the slight tilt of the keyway rib portions 40 prevents an unauthorized user from "thinning" a standard key blade until it fit~ within the tapered keyway 12 of the present invention. Accordingly, the only key blank which can be used to gain acces~ to the keyway 12 is the key blank 9 as is described herein.
OTHER VIE~18 OF TH15 REY B~
FIGS. 6ta-f) show the ornamental design of the key blank 9 o~ one embodiment of the present invention. FIGS. 7(a-g) show the ornamental design of a key blank 7 of another embodiment of 215~3~

the present invention having a reverse configuration of the key groove portions of the key blank shown in ~IGS. 6(a-f).
Whil~ various forms and modifications have been described above and illustrated in the drawings, it will be appreciated that the invention is not limited thereto but encompasses all variations and expedients within the scope of the followinq claims.

Claims (12)

1. A high security lock apparatus comprising:
(a) a lock cylinder;
(b) a plug within the cylinder, said plug being rotatable about an imaginary axis and said plug defining a keyway having first and second opposing keyway sides extending longitudinally within said plug, wherein said first and second opposing keyway sides define, respectively, first and second intersecting imaginary keyway side planes, wherein said first and second imaginary keyway side planes form first and second keyway side angles defined, respectively, by the intersection of said first and second imaginary keyway side planes and an imaginary keyway reference plane defined by a plane crossing a point midway on an imaginary keyway guide region line, which is defined by the greatest width of said keyway, said imaginary keyway reference plane being perpendicular to said imaginary keyway guide region line; and (c) one or more keyway ribs, said keyway ribs protruding from said first and second keyway sides extending longitudinally along said first and second keyway sides.

2. A high security key comprising:
(a) a bow region;
(b) a key guide region; and (c) a key blade region having first and second key sides, said first and second key sides having one or more key grooves extending longitudinally along said first and second key sides, wherein said first and second key sides define first and second intersecting imaginary key side planes, wherein said first and second imaginary key side planes form first and second key side angles defined, respectively, by the intersection of said first and second imaginary keyway side planes and an imaginary key reference plane defined by a plane crossing a point midway on a line extending across the greatest width of said keyway, said imaginary key reference plane being perpendicular to said line.

3. The apparatus of claim 1, wherein the magnitude of said first keyway side angle is not equivalent to the magnitude of the second keyway side angle.

4. The apparatus of claim 2, wherein the magnitude of the first key side angle is not equivalent to the magnitude of the second key side angle.

5. The apparatus of claim 1, wherein the apparatus includes a plurality of pins, each slidably disposed within a pin chamber which intersects the keyway, wherein each pin is adapted to contact each bitting.

6. The apparatus of claim 5, wherein the apparatus includes a plurality of drivers, each slidably disposed within a driver chamber and each driver biased downwardly against one of the pins, wherein each driver may transverse and enter the opposing pin chamber for halting rotation of the plug.

7. The apparatus of claim 1, wherein the first and second keyway side angles are between 1° and 10°.

8. A high security lock apparatus comprising:
(a) a lock cylinder;
(b) a plug within the cylinder, said plug being rotatable about an imaginary axis and said plug defining a keyway having first and second opposing keyway sides extending longitudinally within said plug, wherein said first and second opposing keyway sides define, respectively, first and second intersecting imaginary keyway side planes, wherein said first and second imaginary keyway side planes form first and second keyway side angles defined, respectively, by the intersection of said first and second imaginary keyway side planes and an imaginary keyway reference plane defined by a plane crossing a point midway on an imaginary keyway guide region line, which is defined by the greatest width of said keyway, said imaginary keyway reference plane being perpendicular to said imaginary keyway guide region line, said first and second keyway side angles are between 1° and 10°;
(c) a barrel section and a flange within said plug for holding the plug in said lock cylinder;
(d) one or more keyway ribs, said keyway ribs protruding from said first and second keyway sides and extend longitudinally along said first and second keyway sides, wherein one or more of said keyway ribs are paracentric;
(e) a key having a key blade region having first and second key sides, said key blade having bittings removed therefrom, said first and second key sides having one or more key grooves extending longitudinally along said first and second key sides, said key grooves corresponding to said keyway ribs, and wherein said first and second key sides define first and second intersecting imaginary key side planes, and wherein said first and second imaginary key side planes form first and second key side angles defined, respectively, by the intersection of said first and second imaginary keyway side planes and an imaginary key reference plane defined by a plane crossing a point midway on a line extending across the greatest width of said keyway, said imaginary key reference plane being perpendicular to said line, said first and second key side angles being between 1 ° and 10 °;
(f) a plurality of pins, each slidably disposed within a pin chamber which intersects said keyway, wherein each pin is adapted to contact one of said bittings; and (g) a plurality of drivers, each slidably disposed within a driver chamber formed within said plug, each driver being biased downwardly against one of said pins, wherein each driver may transverse and enter said pin chamber for halting rotation of said plug.

9. The apparatus of claim 8, wherein said first and second keyway side angles and said first and second key side angles are all equivalent.

10. The apparatus of claim 8, wherein the flange extends radially outward.

11. The apparatus of claim 8, wherein the apparatus includes a plurality of springs within the driver chambers for biasing downwardly the drivers.

12. The apparatus of claim 8, wherein the magnitude of the first keyway side angle is not equivalent to the magnitude of the second keyway side angle, and the magnitude of the first key side angle is not equivalent to the magnitude of the second key side angle, the first keyway side angle being equivalent to the first key side angle and the second keyway side angle being equivalent to the second key side angle.
14. A high security lock apparatus comprising:
(a) a lock cylinder;
(b) a plug within the cylinder, said plug being rotatable about an imaginary axis and said plug defining a keyway having first and second opposing keyway sides extending longitudinally within said plug, wherein said first and second opposing keyway sides define, respectively, first and second intersecting imaginary keyway side planes, and upper and lower keyway regions, wherein said first and second imaginary keyway side planes form first and second keyway side angles defined, respectively, by the intersection of said first and second imaginary keyway side planes and an imaginary keyway reference plane defined by a plane crossing a point midway on an imaginary keyway guide region line, which is defined by the greatest width of said keyway, said imaginary keyway reference plane being perpendicular to said imaginary keyway guide region line, said first and second keyway side angles are between 1° and 10° and are equivalent in magnitude;
(c) a barrel section and a flange within said plug for holding the plug in said lock cylinder;
(d) two keyway ribs protruding from said first and second keyway sides, said first and second keyway ribs extending longitudinally along said first and second keyway sides, wherein said keyway ribs are paracentric;
(e) an enlarged keyway rib portion protruding from said second keyway side of said lower keyway region, said enlarged keyway rib portion extending longitudinally along substantially the length of said keyway;
(f) a key having a key blade region having first and second key sides, said key blade having bittings removed therefrom, said first and second key sides having two key grooves extending longitudinally along said first and second key sides, said key grooves corresponding to said keyway ribs, and wherein said first and second key sides define first and second intersecting imaginary key side planes, and wherein said first and second imaginary key side planes form first and second key side angles defined, respectively, by the intersection of said first and second imaginary keyway side planes and an imaginary key reference plane defined by a plane crossing a point midway on a line extending across the greatest width of said keyway, said imaginary key reference plane being perpendicular to said line, said first and second key side angles being between 1 ° and 10 °;
(g) an enlarged key groove portion along said second key side of said lower keyway region, said enlarged key groove portion extending longitudinally along substantially the length of said key side;
(h) six pins, each slidably disposed within a pin chamber which intersects said keyway, wherein each pin is adapted to contact one of said bittings; and (i) six drivers, each slidably disposed within a driver chamber formed within said plug, each driver being biased downwardly against one of said pins, wherein each driver may transverse and enter said pin chamber for halting rotation of said plug.
15. The apparatus of claim 14, wherein said first and second key side angles are 3°.
16. The apparatus of claim 15, wherein said first and second keyway side angles are 3°.

17. The apparatus of claim 14, wherein said first and second key side angles are 4°.
18. The apparatus of claim 15, wherein said first and second keyway side angles are 4°.
19. The apparatus of claim 14, wherein a cross-section of said keyway rib portions form an isosceles triangle, and said key grove portion corresponding thereto.
20. The apparatus of claim 19, wherein a cross-section of said keyway rib portions form a curved line, and said key grove portion corresponding thereto.