Field of the invention
[0001] The present invention relates to a cylindrical lock operable with a rotatable key,
said lock comprising a base body provided with a cylindrical bore, in which bore a
set of annular, particularly concentric plates is arranged, said arrangement substantially
constituting catchers, said catchers being locked against self-rotation and preferably
adapted for engagement with the shank of the rotatable key, with at least one tumbler
as well as with guiding means for aligning the catchers in a position enabling the
rotatable key to be removed from the lock.
Background of the invention
[0002] An overwhelming majority of the down-to-date cylinder locks with rotatable keys,
wherein key actuates lamellar catchers arranged perpendicularly to the former, such
as the cylinder lock mentioned in the background section of the patent document
US 5,388,438 or the cylinder lock disclosed in the European patent
EP 0 989 262, comprises a base body provided with a cylindrical bore, in which a rotatable cylinder
is placed, said cylinder being provided with an entry slot for the tumbler and accommodating
a plurality of catchers, the particular arrangements of the latter creating diverse
locking combinations, or additional discs enhancing the functionality of the cylinder
lock, such as plugs having diverse thicknesses. For example, the additional discs
enhancing the functionality of the cylinder lock may serve as lifters, as disclosed
in
EP 0 989 262.
[0003] A considerable problem of such cylinder lock assemblies consists in the difficult
delimitation of the deviation tolerances along the longitudinal axis of the assembly,
the total deviation tolerance being the sum of the thickness tolerances of the catchers
and those of the additional discs, if any, and the length tolerance of the bore of
the rotatable cylinder. In this respect, it is desirable that the deviation tolerances
embracing those between the catcher sets with the additional discs, if any, and the
rotatable cylinder as well as those between the individual catchers and the individual
additional discs, if any, are mutually compensated so that the position of the combination
tab of each catcher corresponds to the position of the respective combination tab
on the rotatable key with the highest degree of accuracy possible.
[0004] Any delimitation of the deviation tolerances provided by inserting shims having diverse
thicknesses between the catchers or the additional discs, if any, is accomplished
in a statistical or empiric manner since it is not possible to determine the accurate
dimensions in any particular point of the assembly in advance. The tabs on the catchers,
which correspond to the combination tabs on the rotatable key, are made thinner so
that the reduced area of the contact surfaces enables a better compensation of the
deviation tolerances to be achieved. Nevertheless, it is not possible to completely
eliminate the risk that the corresponding combination tabs on the catcher and on the
rotatable key become longitudinally misaligned after the completion of the assembly
of the lock due to disparate tolerances and the complete lock will have do be disassembled
and readjusted.
[0005] The process of manufacturing the rotatable cylinder and, especially, the cylindrical
bore for the insertion of catchers is demanding from the technological point of view,
since the parts involved are typically machined ones.
[0006] Another exemplary drawback of the existing solution according to the disclosure of
EP 0 989 262 consists in that the return rods, which serve to prealign the catchers so that the
latter form a through hole for the shank of the rotatable key enabling the latter
to be removed from the lock, are guided by the edges of the catchers on one side and
by the wall of the rotatable cylinder on the other side. Such a dual guiding arrangement
is also inconvenient because, particularly in connection with small dimensions of
the locks, the impacts of the manufacturing inaccuracies may stack up in a considerable
extent.
[0007] While the above described cylinder lock according
EP 0 989 262 employs return rods for aligning the catchers to enable the insertion of the rotatable
key, the solution constituting the prior art with reference to the patent
US 5,388,438 contemplates the alignment of the catchers of the cylinder lock by means of the adjustable
edges in the holes interacting with the rotatable key during the engagement of the
latter with the catchers.
[0008] The prior art further includes various cylinder locks of the above mentioned type
involving different solutions for locking the catchers against self-rotation (unintended
rotation), the most commonly used technical solution consisting in utilising a friction
force between the catchers and shims having diverse thicknesses for retaining the
same. Said friction force is induced either by the elimination of the tolerances between
the discs by means of variable shims and pressing the discs inside the cavity of the
rotatable cylinder against each other as close as possible, which is the case with
the cylinder lock according
EP 0 989 262, or by means of additional spring-loaded elements. Another known technical solution
is disclosed in
GB 2266119, wherein the discs are subjected to the clamping force induced by a helical spring
arranged behind the disc assembly.
Summary of the invention
[0009] The objective of the present invention is to eliminate the above disadvantages and
drawbacks of the existing technical solutions and to provide a cylinder lock that
would enable the thickness tolerances of the catchers and the additional discs, if
any, to be compensated in the most simple, accurate and reliable manner possible and
that would simultaneously solve the problem relating to the alignment of the catchers
and additional discs inside the cylinder lock in order to substantially simplify the
process of manufacturing the same.
[0010] The above objectives are fulfilled and the above disadvantages and drawbacks are
eliminated by a cylindrical lock operable with a rotatable key, said lock comprising
a base body provided with a cylindrical bore, in which a set of annular plates constituting
at least catchers is arranged axially, said catchers being locked against unintended
rotation and adapted for an engagement with a shank of the rotatable key, with at
least one tumbler as well as with guiding means for aligning the catchers in a position
enabling the rotatable key to be removed from the lock, while according to the invention
a plurality of adjacent spacing shims is arranged axially in the cylindrical bore,
the spacing shims being locked against relative movement, wherein at least the individually
freely rotatable catchers are completely embedded in the spacing shims, which are
adapted for engagement with at least one tumbler, with means for locking the catchers
against unintended rotation and with means for aligning the same in a position enabling
the rotatable key to be removed and the shank of the key to pass through, the last
spacing shim adjoining to the terminating element.
[0011] Preferably, each spacing shim comprises an annular plate provided with an outer contact
surface and an internal surface as well as with a discontinuous unilateral rim terminated
with a frontal contact surface, wherein the distance between the frontal contact surface
and the internal surface exceeding the thickness of the respective catcher, and the
unilateral rim is provided with an internal circumferential surface for holding the
catcher in its functional position, and with an external circumferential surface for
retaining the spacing shim inside the cylindrical bore of the base body, while an
axial through bore for inserting the rotatable key is provided in the annular plate.
[0012] It is also advantageous, when a transversal slot for an insertion of the tumbler
is provided in the circumferential area of each of the spacing shims.
[0013] It is also advantageous, when at least one retaining protrusion extends from the
frontal contact surface of the unilateral rim of each spacing shim and a shaped recess
extending partially in the annular plate is provided in the unilateral rim behind
the retaining protrusion.
[0014] Preferably, a labyrinth hole for a pair of pair of return rods is arranged opposite
to the transversal slot and along the internal circumferential surface of the unilateral
rim of each spacing shim, said hole being provided with two opposed guiding edges
and with an abutment edge at either end, the edges merging into retaining grooves
in the direction towards the internal circumferential surface of the unilateral rim
of the spacing shim.
[0015] Also preferably, the terminating element is formed by a cylindrical body provided
with a blind or through axial bore for an insertion of the end portion of the shank
of the rotatable key and with at least one interconnecting protrusion and a shaped
recess arranged on its frontal side, a peripheral area of the terminating element
being further provided with an open-ended cutout for engagement with a pair of return
rods, the open-ended cutout being provided with a frontal abutment surface and a bottom
surface, which corresponds to a guiding edge arranged on the spacing shim proximally
to the centreline of the same, and which is terminated with end recesses, while -
in the opposite position with respect to the open-ended cutout - the peripheral portion
of the terminating element is further provided with a longitudinal slot matching with
a transversal slot of the spacing shim, and with a transversal notch engaging with
an arresting latch.
[0016] The most significant advantage of the cylinder lock according to the invention consists
in that the total deviation tolerance of the locking system is composed merely of
the sum of the deviation tolerances of the outer thicknesses T3 of the spacing shims.
The thickness tolerances of the catchers are compensated in that the dimensions of
the catchers are included in the functional widths T1 of the spacing shims, i.e. between
the frontal contact surface and the internal surface of the individual spacing shims.
The above surfaces partly keep the catcher in a relatively stable position and partly
enable the catcher to be displaced within a small axial range, which displacement
compensates any possible deviation between the positions of the coding tab of the
catcher and that of the rotatable key during the insertion of the key.
[0017] The solution according to the invention further enables the relatively long thin-walled
rotatable cylinder, which is one of the parts that must be unavoidably manufactured
by machining, to be replaced with a series of spacing shims, each being producible
using a more effective manufacturing method, such as stamping or precise casting.
[0018] The solution according to the invention also enables the return rods, when the latter
are included in the mechanism, to be guided in a relatively precise manner, namely
by means of enclosed grooves formed in the spacing shims and the catchers to be more
securely locked against self-rotation by means of the return bars, said bars being
held in the locking positions by the relatively precise shaped edges of the above
mentioned enclosed grooves.
Brief description of the drawings
[0019] An exemplary embodiment of the invention is shown in the attached drawing, wherein
Fig. 1 shows the cylinder lock in a perspective exploded view, Fig. 2 shows the assembled
cylinder lock in a front view, Fig. 3 shows the cylinder lock in an enlarged partial
sectional view, wherein the section is led through the plane III - III as indicated
in Fig. 2, Fig. 4 shows a front view of one of the spacing shims, Fig. 5 shows the
spacing shim in a vertical sectional view, wherein the section is led through the
plane V - V as indicated in Fig. 4, Fig. 6 shows a perspective view of the terminating
element, Fig. 7 shows a front view of the terminating element, Fig. 8 shows a side
view of the terminating element, Fig. 9 shows a front view of the cylindrical collar,
Fig. 10 shows an axial cross-sectional view of the cylindrical collar and Fig. 11
shows the perspective view of the assembly comprising the adjusting cylinder with
the cylindrical collar along with a part of the series of the spacing shims with the
catchers and lifters, with the pair of return rods and with the terminating element.
Exemplary embodiment of the invention
[0020] The cylinder lock according to the invention comprises a base body
1 (Fig. 1) provided with a cylindrical bore
2, in which a series of spacing shims
3 is arranged, in which arrangement standard individual freely rotatable catchers
4 and lifters
5 are embedded.
[0021] In Fig. 1, the first of the catchers
4 in the series shown is the one which is not embedded in the spacing shim
3, since it is possible to arrange the first catcher inside the internal space of a
cylindrical collar
6 so that only the subsequent catcher
4 is placed in the first spacing shim
3. Especially the outer catchers
4 or lifters
5 may also be arranged outside the spacing shim
3.
[0022] The catchers
4 are provided with standard open-ended notches
7 having rounded bottom portions and outer edges
8,
9. The lifters
5 are also provided with standard open-ended notches
10 having rounded bottom portions and they are terminated by standard recesses
11,
12 interacting with a standard pair of return rods
13.
[0023] The front end of the above assembly adjoins to a standard adjusting means
14 which, in the present exemplary embodiment, comprises an adjusting cylinder
15 with a profiled opening
16 and is provided with a guiding element
17 protruding, when assembled, into the system of the spacing shims
3 with the catchers
4 and lifters
5. The adjusting cylinder
15 comprises a standard assembly of safety balls
18 and retaining balls
19 spaced inside the adjusting cylinder
15 of the cylinder lock by means of expander springs
20. The adjusting cylinder
15 is inserted in the cylindrical collar
6 along with a shield
21 provided with a guiding opening
22. On one of its sides, the cylindrical collar
6 is provided with at least one element enabling non-rotational interconnection with
the first spacing shim
3. Besides that, the spacing shims
3 may be provided with special elements enabling the same to be interconnected with
the cylindrical collar
6. In the present exemplary embodiment, said elements enabling non-rotational interconnection
of the cylindrical collar
6 and the first spacing shim
3 (Figs. 1, 4 and 5) are formed by interconnecting projections
23 arranged mirror-symmetrically on the cylindrical collar
6 and by transversal notches
24 (Fig. 4) arranged on the spacing shims
3. The cylindrical collar
6 (Fig. 9) is also adapted for the insertion of the ends of the standard pair of return
rods
13 through a labyrinth cutout
25 with recesses
26 a
27, into which the ends of the return rods
13 enter when the mechanism of the cylinder lock is rotated. Opposite to the labyrinth
cutout
25, a blind slot
28 for the insertion of an end portion of a tumbler
29 is arranged. An annular shoulder
30 encloses a frontal pocket
31 for the insertion of the first tumbler
4 of the series. At its opposite end, the cylindrical collar
6 is provided with a cylindrical recess
32 for inserting the adjusting cylinder
15. At the same end, the collar is also adapted (in a manner which is known in the art)
for engagement with a projection
33 formed on the adjusting cylinder
15 and provided with a pair of opposed grooves
34, also known in the art, for accommodating the safety balls
18. Fig. 1 shows only one of the grooves
34.
[0024] On the opposite side, the series of spacing shims
3 is adjoined by a terminating element
35 provided with a pair of compression springs
36 and with an arresting latch
37. On the reverse side, the terminating element
35 accommodates a carrier
38, which simultaneously engages with a finger
39 for controlling an adjoining mechanism (not shown) of the cylinder lock. Between
the terminating element
35 and the finger
39, a disc spring
40 is arranged.
[0025] As shown in Figs. 4 and 5, each of the spacing shims
3 is provided with an annular plate
69 having an outer contact surface
43 and an inner surface
42. A part of the peripheral area of the spacing shim
3 is provided with a discontinuous unilateral rim
70 concluded with a frontal contact surface
41, wherein the distance between the frontal contact surface
41 and the internal surface
42 equals the inner functional width
T1 of the spacing shim
3. Said inner functional width
T1 always exceeds the thickness
T2 (Fig. 3) of the respective insertion element, i.e. the catcher
4, or that of the lifter
5, if any. Each of the spacing shims
3 is further provided with an opposite contact surface
43 (Fig. 5) arranged on the reverse side of the spacing shim
3 and extending in parallel with respect to the frontal contact surface
41, the distance between the frontal contact surface
41 and the outer contact surface
43 being equal to the outer functional width
T3 of the spacing shim
3. The discontinuous unilateral rim
70 of each of the spacing shims
3 is further provided with an internal circumferential surface
44 for holding the respective catcher
4 in its functional position as well as with an external functional surface
45 for retaining the respective spacing shim
3 inside the cylindrical bore
2 of the base body
1 of the cylinder lock (Fig. 1). The annular plate
69 of each of the spacing shims
3 is further provided with an axial bore
46, which may be circular in shape, for inserting a rotatable key (not shown) and with
a transversal slot
47 arranged in the circumferential portion and adapted for guiding the standard tumbler
29 (Fig. 1, 4, 5). Furthermore, each spacing shim
3 is provided with a labyrinth hole
48 arranged along the unilateral rim
69 and opposite to the transversal slot
47, said hole adapted for accommodating a pair of standard return rods
13 being arranged along the entire length of the assembly of the spacing shims
3 and extending into the terminating element
35 and the cylindrical collar
6. The labyrinth hole
48 is provided with two opposed guiding edges
49,
50 and with two abutment edges
51,
52 at either end, the latter merging into retaining grooves
53,
54 in the direction towards the internal circumferential surface of the spacing shim
3. Each of the spacing shims
3 is provided with at least one retaining protrusion
55 extending from the frontal contact surface
41 of the unilateral rim
70, wherein the shaped recess
56 is formed in the unilateral rim
70 behind the retaining protrusion
55 and it extends partially in the annular plate
69 of the spacing shim
3. In the exemplary embodiment, four retaining protrusions
55 with four respective shaped recesses
56 are shown. Each of the retaining protrusions
55 of the respective spacing shim
3 extends into the shaped recess
56 of the adjacent spacing shim
3 within the assembly of the cylinder lock. Thus the adjoining spacing shims
3 are locked against relative rotational movements.
[0026] The terminating element
35, which has the shape of a relatively low cylinder, is provided with at least one
element enabling a non-rotational interconnection with the last spacing shim
3. In the exemplary embodiment, the terminating element
35 (Figs. 6, 7, 8) is provided with two interconnecting projections
57 and four shaped recesses
58. The terminating element
35 is further provided with an, at least blind, axial bore for the insertion of the
end portion of the shank of the rotatable key (not shown). In the exemplary embodiment,
the terminating element
35 is provided with a through bore
59 adjoining to the axial bores
46 of the spacing shims
3.
[0027] In its circumferential portion, the terminating element
35 is provided with an open-ended cut-out
60 for the insertion of the standard return bars
13. A frontal abutment surface
61 of the open-ended cut-out
60 delimits the end positions of the return bars
13 and the bottom surface
62 along with end recesses
63,
64 of the open-ended cut-out
60 are intended for guiding the return bars
13 during their functional movements. The terminating element
35 is further provided with a longitudinal slot
65 having the same purpose as the transversal slots
47 of the spacing shims
3, namely to enable an insertion of the tumbler
29. The opposite side of the terminating element
35 may be adapted for an interconnection with various adjoining parts (not shown). According
to the present exemplary embodiment, the terminating element
35 is provided with a segmented collar
66 for the shape-based connection with the carrier
38 and for retaining the disc spring
40 slipped over the same.
[0028] The terminating element
35 is further provided with a transversal notch
67 created therein in a known manner and serving for the insertion of the compression
springs
36 and the arresting latch
37, the latter engaging with a corresponding cut-out (not shown) created in the base
body
1. The design and the functions of the compression springs
36 and the arresting latch
37 are analogous to the embodiments known in the art, which means that the above parts
serve to retain the set of the spacing shims
3 and to lock it against rotation during the alignment of the catchers
4 enabling the latter to assume the positions that are necessary for the insertion
of the shank of the rotatable key.
[0029] The spacing shims
3 may also be provided with special means enabling the interconnection with the terminating
element
35. In the exemplary embodiment the above means are formed by the transversal notch
24 for the insertion of the interconnecting projection
57 of the terminating element
35 and by the retaining protrusion
55 that engages with the shaped recess
58 of the terminating element
35.
[0030] The cylindrical bore
2 of the base body
1 of the cylinder lock is provided with a longitudinal notch
68 formed therein (Fig. 3), into which the tumbler
29 partially extends.
[0031] The above mentioned standard pair of return bars
13 acts as usual means for transferring the torque from the lifters
5 to the spacing shims
3, as a means for returning the catchers
4 into the positions enabling the rotatable key to be removed and as a means for preventing
any unintended rotation of the catchers
4, since in the idle condition of the cylinder lock each of the return bars
13 is pushed by the guiding edges
49 of the labyrinth holes
48 into one of the recesses
11,
12 of the respective lifter
5 and simultaneously abuts against one of the outer edges
8,
9 of the open-ended notches
7 formed in the catchers
4. The return bars
13 are held in the recesses
11,
12 in that the rounded bottom surfaces of the open-ended notches
10 formed in the lifters
5 extend into the space between the guiding edges
49,
50 of the labyrinth holes
48, thus preventing the return bars
13 from protruding into the same space.
[0032] The operation of the above described cylinder lock according to the invention is
as follows:
When the rotatable key (not shown) is being inserted into the cylinder lock, the shank
(not shown) of the former first passes through the guiding opening 22 formed in the sheet 21 arranger inside the cylindrical collar 6 and then it passes through the profiled opening 16 formed in the adjusting cylinder 15. Afterwards, the shank passes through the guiding element 17, by which it is held and guided, and simultaneously through the set of spacing shims
3 that accommodate the corresponding catchers 4 and lifters 5. Thus, the guiding element 17 prevents the frontal face of the shank of the rotatable key from coming into direct
contact with the catchers 4 and lifters 5. In this manner, the latter are protected from any undesirable or inadvertent manipulation.
During the final stage of the insertion process, the end of the shank of the rotatable
key reaches the end of the guiding element 17 and enters into the terminating element 35, which causes the adjusting cylinder 15 to be unlocked with respect to the cylindrical collar 6, said unlocking action being accomplished by means of the safety balls 18 and retaining balls 19, i.e. in a generally known manner. When accomplished, the above unlocking action
enables the adjusting cylinder 15, the guiding element 17 and the key itself to be rotated.
[0033] The rotation of the rotatable key (not shown) causes the cylinder lock to be locked
or unlocked in a completely known manner. During such action, the coding projections
(not shown) formed on the shank of the rotatable key come into contact with the coding
tabs (also not shown) formed in the catchers
4. Since the catchers
4 are arranged inside the corresponding spacing shims
3 with a certain amount of clearance and, at the same time, very precisely longitudinally
aligned with respect to the shank of the rotatable key, the coding projections on
the shank very precisely engage with the coding tabs in the catchers
4, driving the latter successively in rotation.
[0034] Simultaneously, the lifters
5 are also successively driven in rotation. Thus, the lifters
5 cause one of the return bars
13 to move in a well known manner. During its movement, the return bar
13 is guided by the guiding edges
49,
50 of the labyrinth holes
48 formed in the spacing shims
3, said guiding action preventing the return bar from touching the rounded bottom portions
of the open-ended notches
7 formed in the catchers
4. Depending on the direction of rotation, the lifters
5 displace the driven return bar
13 up to the respective abutment edge
51,
52 of the labyrinth hole
48, where that driven return bar
13 strikes against the other return bar
13 (not shown), forcing the same into one of the respective retaining grooves
53,
54 formed in the corresponding labyrinth holes
48. The engagement of the return bars
13 with the respective abutment edge
51,
52 cause the spacing shims
3 to rotate. During the unlocking action, the rotation of the spacing shims
3 pushes the tumbler
29 out from the longitudinal notch
68 of the base body
1. After having been displaced from the longitudinal notch
68 of the base body
1, the tumbler
29 enters farther into the transversal slots
47 formed in the spacing shims
3 and into the longitudinal slot
65 formed in the terminating element
35. At the same time, tumbler
29 enters into the slots formed in the catchers
4 and lifters
5 that have been adjusted against the former by means of the movement of the rotatable
key. This enables the entire internal arrangement of the cylinder lock to be driven
in rotation and all the necessary operations to be accomplished.
[0035] During the rotational movement of the assembly, the respective return bar 13 and
the tumbler
29 act as driving means causing those parts to rotate which are not in direct contact
with the rotatable key, such parts particularly including the spacing shims
3 and also the terminating element
35. The additional driving means comprise the coupled retaining protrusions
55 and the shaped recesses
56 of the spacing shims
3 along with the means for interconnecting the last spacing shim
3 and the terminating element
35. During the initial stage of the rotational action of the key, the cylindrical collar
6 is locked by the adjoining spacing shim
3. After the spacing shims
3 have become unlocked by the tumbler
29, the cylindrical collar
6 is driven in the direction of rotation in a known manner, namely by the projection
33 formed on the frontal face of the adjusting cylinder
15 and also by means of the pair of return bars
13.
[0036] During the locking action, the tumbler 29 is pushed out of the slots formed in the
catchers
4 and, also in a known manner, inserted back into the longitudinal notch
68 formed in the base body
1. This is accomplished by means of the inclined walls of the slots formed in the lifters
5 to facilitate the insertion of the tumbler
29.
[0037] The removal of the rotatable key is enabled in that the catchers
4 are aligned, again in the known manner. First, the key is turned to the position
which enables the tumbler
29 to be aligned with the longitudinal notch
68 of the base body
1 and the arresting latch
37 to engage with the corresponding cut-out (not shown) formed in the base body
1, causing the terminating element
35 and hence also the spacing shims
3 to be locked against rotation. Afterwards, the rotatable key is turned in the opposite
direction into such angular position that enables the catchers
4 to be aligned under the action of the return bars
13 so that the openings of the latter stop preventing the rotatable key from being removed
from the lock.
Industrial applicability
[0038] The technical solution according to the invention may be utilized for designing and
manufacturing cylinder locks with rotatable keys, particularly when a more sophisticated
and accurate design and more cost-effective production are required.
List of reference signs
[0039]
- 1
- base body
- 2
- cylindrical bore
- 3
- spacing shim
- 4
- catcher
- 5
- lifter
- 6
- cylindrical collar
- 7
- open-ended notch
- 8
- outer edge
- 9
- outer edge
- 10
- open-ended notch
- 11
- recess
- 12
- recess
- 13
- return bar
- 14
- adjusting means
- 15
- adjusting cylinder
- 16
- profiled opening
- 17
- guiding element
- 18
- safety ball
- 19
- retaining ball
- 20
- expander spring
- 21
- shield
- 22
- guiding opening
- 23
- interconnecting projection
- 24
- transversal notch
- 25
- labyrinth cutout
- 26
- recess
- 27
- recess
- 28
- blind slot
- 29
- tumbler
- 30
- annular slot
- 31
- frontal pocket
- 32
- cylindrical recess
- 33
- projection
- 34
- groove
- 35
- terminating element
- 36
- compression spring
- 37
- arresting latch
- 38
- carrier
- 39
- finger
- 40
- Disc spring
- 41
- frontal contact surface
- 42
- internal surface
- 43
- opposite contact surface 44 internal circumferential surface
- 45
- external circumferential surface
- 46
- axial bore
- 47
- transversal slot
- 48
- labyrinth hole
- 49
- guiding edge
- 50
- guiding edge
- 51
- abutment edge
- 52
- abutment edge
- 53
- retaining groove
- 54
- retaining groove
- 55
- retaining protrusion
- 56
- shaped recess
- 57
- interconnecting projection
- 58
- shaped recess
- 59
- through axial bore
- 60
- open-ended cut-out
- 61
- frontal abutment surface
- 62
- bottom surface
- 63
- end recess
- 64
- end recess
- 65
- longitudinal slot
- 66
- segmented collar
- 67
- transversal notch
- 68
- longitudinal notch
- T1
- inner functional width
- T2
- thickness
- T3
- outer functional width