Cylinder locks having removable barrels

Abstract: A cylinder lock having a removable barrel (12) that includes a control tumbler (13). The barrel (12) is retained in the housing (11) of the lock by a nib that is formed on either the barrel (12) or the interior of the housing (11). A longitudinal nib slot (21) is formed on the other of either the barrel or the interior of the housing (11). The nib and the nib slot (21) are aligned with one another only when the barrel is in an unlocking position for permitting the barrel to be removed from the housing (11). In this manner, the barrel (12) may be removed from the housing (11) only when both the barrel (12) is in the unlocked position and when a special control key (2) has been inserted into the barrel (12) for withdrawing the control tumbler into the barrel (12).

Description: The present invention relates to a unit comprising a lock system, according to the preamble of claim 1. Such a system is described in the European Patent Application No. 350,474 of Applicant. In this patent application a key-activated removable cylinder is disclosed. The lock has a lock barrel including a plurality of combinating tumblers disposed therein for movement between a first resting position and a second activated position. The barrel further includes a control tumbler having a first end and a second opposite end. The control tumbler is slidably disposed between a first resting position and a second activated position. In the resting position, the first end is extended relative to the barrel. In the activated position, the first end is retracted relative to the barrel. A housing rotatably removably receives the barrel therein. The housing further has an internal longitudinal slot formed therein extending from a forward end thereof. An annular clearance space is located rearwardly of the slot and is in communication therewith for accommodating extension of the first end of the control tumbler in the resting position, whereby rotational movement of the barrel in the housing is permitted. The width of the first end is greater than the width of the slot and the second end, such that when the control tumbler is in the resting position, removal of the barrel from the housing is prevented. Insertion of a first normal key moves the combinating tumblers into their respective activated positions, whereby the barrel may rotate for the locking and unlocking thereof. Insertion of a second removal key moves the control tumbler into the resting position thereof for the removal of the barrel therefrom. For some purposes however there is a request for a lock having a lock barrel which does not rely solely on the use of a control tumbler to retain the lock barrel in the housing, so as to be capable of withstanding greater amounts of stress than those disclosed in our European Patent Application No. 350,474. Summary of the Invention Accordingly, it is the primary object of the present invention to provide a cylinder lock having a removable barrel in which the barrel is removably retained in the housing by an arrangement that utilizes element(s) other than a control tumbler as the primary means for retaining the barrel in the housing, so that a retaining means is provided that is capable of withstanding increased amounts of pressure, and further so that the lock barrel cannot be partially dislodged from the housing during locking and unlocking operations. It is still another primary object of the present invention to provide such a lock that has a housing, a removable barrel and sliding combinating tumblers, and in which the removable barrel may be easily installed or replaced only when the lock barrel is in an unlocked position. It is another object of the present invention to provide a lock which can be easily fabricated without encountering problems with manufacturing standardization, and which utilizes standardized parts that are adaptable for use in a wide variety and range of locks, thereby reducing problems with inventory. It is a still further object of the present invention to provide a lock which is simple to manufacture and does not require inserts or piece for abutment, even when a 360° annular rotation of the annular groove is provided. In accordance with the teachings of the present invention, it is proposed to equip the lock barrel with a nib and to fit out on the interior of the housing a nib slot as well as an annular clearance space to receive the nib. It is to be noted that French Patent Application No. 2,610,031 discloses the use of a nib, but according to this document the tub is formed on the housing and the nib slot on the lock barrel. This solution gives rise to a lock barrel which becomes extra long, as the nib clearance and the nib slot are to be placed backwards the combinating tumblers and the control tumbler. Furthermore, the fabrication of a barrel with both a nib clearance and a nib slot is complicated. It is further difficult and not economical to drill each housing to insert a pin in the housing. It is further unpractical for assembly reasons as the cam carrier needs to be assembled before the drilling and pinning operations are made. This gives rise to additional inventory and costs. There is consequently a need to propose a lock barrel which does not present these drawbacks, and which gives rise to a barrel of acceptable, preferably short dimensions, easy to produce and easy to assemble without unnecessary cost problems. The unit according to the invention comprises a lock system, operated with the help of a locking key. The unit is of the type having a housing and a removable cylinder barrel, which can be removed from the housing with the help of a removal key. The barrel includes a plurality of sliding combinating tumblers disposed in the barrel for movement between respective resting positions and respective activated positions, and further includes a sliding control tumbler having a first end, this control tumbler being disposed in the barrel for movement between a resting position, wherein the first end is extended relative to the barrel and an activated position, wherein the first end is retracted relative to the barrel. The housing has a bore for rotatably receiving the barrel, an internal longitudinal slot extending from the forward end of the housing and an annular clearance space located rearwardly the internal slot for accommodating the extended first end of the control tumbler in its resting position, so that the barrel is retained in the housing. The insertion of the locking key into the barrel slidingly moves the combinating tumblers into their respective activated positions so that all of the tumblers are withdrawn relative to the barrel permitting rotational movement of the barrel in the housing for the locking and unlocking thereof, but maintains the control tumbler in its resting position, thereby preventing removal of the barrel from the housing. The insertion of the removal key into the barrel slidingly moves the control tumbler into the activated position, wherein its first end is retracted relative to the barrel, thereby no longer preventing the barrel to be removed from the housing. The above mentioned problems are solved by the characterizing features stated in claim 1. These and other objects of the present invention will become readily apparent from the following specification taken in conjunction with the enclosed drawings. Brief Description of the Drawings Figure 1A is a longitudinal cross-section of a conventional cylinder lock having a removable barrel and a control tumbler. Figure 1B is an end view of the lock of figure 1A. Figure 2A is a longitudinal cross-section of the conventional lock of figure 1A, with a normal key inserted therein. Figure 2B is an end view of the lock of figure 2A. Figure 3A is a longitudinal cross-section of the conventional lock of figure 1A, with a removal key inserted therein. Figure 3B is an end view of the lock of figure 3A. Figure 4A is a longitudinal cross-section of a first embodiment of the lock of the present invention with the lock barrel thereof in an unlocked (open) position, with the normal key inserted therein and with the longitudinal nib slot formed in the housing being illustrated in phantom lines for the sake of clarity. Figure 4B is an end view of the lock of figure 4A. Figure 5 is a cross-section view of the first embodiment of the lock of the present invention taken along lines 5-5 of figure 4A. Figure 6A is a longitudinal cross-section, view of the first embodiment of the lock of the present invention with the lock barrel thereof in a locked (closed) position and with the normal key inserted therein. Figure 6B is an end view of the lock of figure 6A. Figure 7A is a longitudinal cross-section view of the first embodiment of the lock of the present invention with the lock barrel thereof in a unlocked (open) position and with the control key inserted therein. Figure 7B is an end view of the lock of figure 7A. Figure 8A is a longitudinal cross-section view of the first embodiment of the lock of the present invention with the lock barrel thereof in a locked (closed) position and with the control key inserted therein. Figure 8B is an end view of the lock of figure 8A. Description of Preferred Embodiments Referring now to the drawings, and in particular, to figures 1A, 1B, 2A, 2B, 3A and 3B a conventional cylinder lock 10 of the type having a housing 11 that rotatably receives and houses therein a removable barrel 12 that includes a control tumbler 13, is illustrated. The lock barrel 12 of the lock assembly 10 is substantially cylindrical in shape having a curvature 14. The lock barrel 12 includes a body 15 and a plurality or series of sliding (combinating) tumblers 16. Tumblers 16 are disposed in the body 15 for sliding movement between respective first resting positions, wherein the rotation of the lock barrel 12 in the housing 11 is prevented, and second activating positions, wherein the rotation of the barrel 12 in the housing 11 is permitted, in a manner that is well known to those skilled in the art. In such locks 10, the control tumbler 13, is slidably disposed in the body 15 normally being located behind (rearwardly of) the tumblers 16. The curvature of the edge of the control tumbler 13 is, preferably, substantially identical to the curvature 14 of the body 15 of the barrel 12. The control tumbler 13 is further retained in the barrel 15 by mechanical means (not illustrated), that are also well known to those skilled in the art. Preferably, this tumbler 13 is normally maintained in a position that is substantially eccentric relative to the tumblers 16. It is noted that while described herein as a barrel having a control tumbler, if desired, a conventional lock that has a removable barrel but does not have a control tumbler may also be utilized. The housing 11 of the present invention has a bore 17 formed therethrough for rotatably receiving the barrel 12 therein. The barrel 12 is removably retained in the housing 11 by the collaboration (abutment) of the control tumbler 13 with a rim that is defined by a peripheral (annular) space 18 that is formed in the bore 17 or located (defined) at the end of the bore 17, being defined by an annular clearance space 18. This annular clearance space 18 is sized to accomodate the extension of the first end of the control tumbler 13. In this fashion, when this control tumbler 13 is in the resting position thereof, wherein the control tumbler 13 extends outwardly from the body 15 of the barrel assembly 12, it is received in the annular clearance space 18 that is located rearwardly of the slot 19. Further, in this manner, removal of the barrel assembly 12 from the housing 11 is prevented when the control tumbler 13 is in the resting position thereof. An (first) internal longitudinal slot 19 is formed in the housing 11 extending rearwardly from a one end (a forward end) of the bore 17 of the housing 11. This slot 19 is in open communication with the bore 17 that is formed through the housing 11. The width of this slot 19 is always less than the width of the control tumbler 13. A second internal longitudinal slot 20 may also be formed in the bore 17 of the housing 11 diametrically opposite of the first slot 19. This second slot 20, like the first slot 19, extends rearwardly from the forward end of the bore 17 of the housing 11. The first slot 19 and the second slot 20 are sized to accommodate the extension of the various combinating tumblers 16 in their resting position. While shown herein as terminating short of the rearward end of the housing 11, in the event that a double-ended control tumbler is utilized, then the first slot 19 will extend to the clearance space 18 through the rim. However, unlike the first slot 19, this second slot 20 will terminate short of the annular clearance space 18, being separated therefrom by the rim. It is also noted that as long as the first end of the control tumbler 13 has a width that is greater than the width of the slots 19 and 20 then, if desired, both of the slots 19 and 20 could extend through the rim. However, such an arrangement is not preferred. In this fashion, in the respective resting positions thereof, at least a portion of the combinating tumblers 16 extends from the diameter (curvature) 14 of the body 15 of the barrel 12, being received in one of the aforementioned longitudinal slots 19 and 20 that are formed in the interior of the housing 11. This prevents the rotational movement of the lock barrel 12 in the housing 11 for the locking and unlocking thereof. Furthermore, in this position the control tumbler 13 also extends from the diameter 14 being received in the annular clearance slot 18 that is either formed in, or defined behind the housing 11, as is perhaps most clearly represented in the end views (figures 2B and 3B). With reference now to figures 2A and 2B, in the conventional lock 10 described above, with the introduction (insertion) of a first normal key 1 having a first bitted portion into the barrel, at least a portion of the sliding tumblers 16 are returned (urged) to the respective activated positions thereof wherein the tumblers 16 are withdrawn into the barrel 12, in a manner known to those skilled in the art. As illustrated herein, these activated positions are retracted relative to the barrel 12, so that the tumblers 16 are positioned at the level of the diameter 14 of the body 15 of the barrel 12. In this activated position, the rotation of the barrel assembly 12 between the first locking and the second unlocking positions is permitted for the locking and unlocking of the lock by use of the normal key 1. Because in such arrangements, the point of the key 1 freely enters into a central opening formed in the control tumbler 13, said 12 key either does not or only slightly touches an edge of the control tumbler 13, such that the control tumbler 13 is not completely withdrawn into the body 15 of the barrel assembly 12 or slid into the activated position. Thus, the control tumbler 13 is not sufficiently displaced and substantially remains in the eccentric first resting position, thereby retaining the barrel 12 in the housing 11 by abutting with the front wall of the annular clearance space 18 in a manner that is well known by those skilled in the art, and as is perhaps most clearly shown in the figure 2B. With reference now to figures 3A and 3B, in the conventional lock 10 described above, with the introduction (insertion) of a second, control key extraction key 2 having a portion with a simplified contours, this portion contacts the control tumbler 13. This collaboration slidingly displaces (retracts) the control tumbler 13 inwardly relative to the body 15 (in figures 3A and 3B in an inwardly direction) until the edge of the control tumbler 13 is in the activated position, wherein said edge at least coincides with the diameter 14 of the body 15 of the barrel 12. If a one-ended control tumbler 13 is utilized, then upon insertion of the control key 2, the barrel 12 may then be removed from the housing 11. However, if a double-ended control tumbler 13 is utilized, then the lock must be in the unlocked position in order to be withdrawn from the housing 11. Because this removal key 2 does not possess the conditions that are typical of the normal key 1, at least a portion of the tumblers 16 remain in the resting positions thereof, not being withdrawn into the respective activated positions thereof (which, as illustrated, are within the body 15 of the barrel 12). Thus, rotation of the barrel 12 in the housing 11, such as is necessary for locking and unlocking of the lock 10 by use of this key 1, is prevented. With reference now to figures 4A-8B, a first embodiment of a lock 10 according to the present invention is discussed. The housing 11 of the lock 10 has an internal longitudinal nib slot 21 formed therein, so as to extend from a forward portion of the housing 11 to the annular clearance space 18, so as to be in communication therewith. At least one nib 22 is formed on the lock barrel 12. The nib 22 is disposed on a portion of the barrel 12, such that when the barrel 12 is disposed in the housing 11, the nib 22 is received in the clearance space 18, permitting rotation of the barrel 12 in the housing 11 between the first locking and the second unlocking positions. The nib 22 is further positioned, so as to be substantially aligned with the nib slot 21 only when the barrel 12 is in the second unlocking position. In the above manner, where the lock 10 is in the locked position (figures 6A, 6B, 8A and 8B), the barrel 12 will be retained in the housing 11 by the nib 22 abutting a section of the housing 11 that is defined by the front of the annular clearance space 18. This is true regardless if the normal key 1 (figures 6A and 6B) or the control key 2 (figures 8A and 8B) is inserted. Further in the above manner, when a control tumbler 13 is provided, even when the lock is in the unlocked position (figures 4A, 4B, 7A and 7B), the barrel 12 will only be able to be removed from the housing 11 when both the control key 2 is utilized and when the barrel 12 is in the unlocking position. As can be seen in figures 4A and 4B, even when the barrel 12 is in the unlocking position, if only the normal key 1 is utilized, the barrel 12 will still be retained in the housing 11 by the control tumbler 13 abutting the front surface of the annular clearance slot 18. As can be seen in figures 7A and 7B, only when both the barrel 12 is in the unlocking position and when the control key 2 is inserted, will the barrel 12 be able to be removed from, the housing 11. Having thus described the present invention, it will be understood by those skilled in the art that, within the scope of the appended claims, the invention may be practiced other than has been specifically described herein. For example, if desired, more than one nib and corresponding nib slots therefor may be utilized as desired to provide further strength and security. Also, if desired, nibs as well as nib slots and annular clearance slots may be formed on both the barrel and the housing in the same embodiment.

Claims: A unit comprising a lock system (10), operated with the help of a locking key (1), of the type having a housing (11) and a removable cylinder barrel (12), adapted for rotation in the housing in any desired position between 0° and 360° and which can be removed from the housing (11) with the help of a removal key (2), not usable for locking and unlocking the system, whereby ; the barrel (12) includes a plurality of sliding combinating tumblers (16) disposed in the barrel for movement between respective resting positions and activating positions, and whereby ; the housing (11) has a bore for rotatably receiving the barrel (12) and an internal longitudinal slot (19) extending from a forward end of the housing ; such that when the barrel is disposed in the housing with the combinating tumblers (16) in the activated positions, the barrel may rotate between a locking and an unlocking position ; and when at least part of the combinating tumblers (16) are in resting positions, they are received in the slot (19) for preventing rotational movement of the barrel in the housing between the locking and unlocking positions thereof ; characterized in that the barrel (12) comprises a nib (22) and that the housing comprises an annular clearance space (18) and a longitudinal nib slot (21) extending from a forward end of the housing to the annular clearance space (18), so as to be in communication therewith, such that when the barrel (12) is disposed in the housing (11), the nib (22) is received in the annular clearance space (18) permitting the rotation of the barrel in the housing between the locking and unlocking positions ; and in that the nib (22) is positioned so as to be substantially aligned with the nib slot (21) only when the barrel is in the unlocking position, whereby the barrel may be removed from the housing with the help of the removal key only when the barrel is in the unlocked position. A unit according to claim 1, characterized in that it further includes a sliding control tumbler (13) to be accommodated in the annular clearance space (18) and having a first end, this control tumbler being disposed in the barrel for movement between a resting position, wherein the first end is extended relative to the barrel and an activated position, wherein the first end is retracted relative to the barrel and whereby ; the insertion of the locking key (1) into the barrel slidingly moves the combinating tumblers (16) into their respective activated positions so that all of the tumblers are withdrawn relative to the barrel permitting rotational movement of the barrel in the housing (11) for the locking and unlocking thereof, but maintains the control tumbler (13) in its resting position, thereby preventing removal of the barrel from the housing ; the insertion of the removal key (2) into the barrel slidingly moves the control tumbler (13) into the activated position, wherein its first end is retracted relative to the barrel, thereby no longer preventing the barrel to be removed from the housing (11). A unit according to claim 1 or 2, characterized in that the annular clearance space (18) is formed in a rearward portion of the housing (11). A unit according to any of claims 1 to 3, characterized in that the housing (11) comprises an annular clearance space positioned to receive the nib (22) and a second annular clearance space positioned to receive the control tumbler (13) when the barrel (12) is disposed in the housing. A unit according to any of claims 1 to 4, characterized in that the first end of the control tumbler (13) has a width which is greater than the internal longitudinal slot (19) of the housing (11).

Inventors: CERON DANIEL, LODOMEZ CHRISTIAN, CERON, DANIEL, LODOMEZ, CHRISTIAN
Applicants: EURO LOCKS NV, S.A. EURO-LOCKS N.V.
Application year: 1991
Main classification: E05B29
IPC codes: E05B9, E05B29