1
=
VEHICLE TIRE
FIELD
-- The invention relates to a directional vehicle tire having a tread profile
and having spikes which
are composed of a spike body and of a spike pin, wherein the spike pin with an
encircling grip
edge which forms a grip edge situated in front in a direction of rotation
during forward travel and
a grip edge situated behind in the direction of rotation, which grip edges
each extend over the
entire width, formed in an axial direction A of the tire, of the spike pin,
wherein the grip edge
length, effective in a circumferential direction U of the tire, of the
encircling grip edge is greater
than the grip edge length effective in the axial direction A, wherein the grip
edge situated in front
in the direction of rotation during forward travel is formed in the direction
of rotation with two
grip edge portions converging on one another in tapering fashion, wherein the
spike body is
formed from a foot flange, a central portion and a top flange, wherein the top
flange and the
central portion are formed in each case with a circular, oval or elliptical
section contour in the
section planes formed perpendicular to the longitudinal extent of the spike.
BACKGROUND
It is known for spiked tires to be formed with spikes, wherein the spikes are
formed with a
geometry of their spike pin in which the extent length in an axial direction
of the tire is greater
than that in a circumferential direction, in order to thus make it possible to
realize good ice grip
characteristics for traction and braking. Here, the spike and the spike pin
are normally designed
to be of symmetrical form with respect to the traction and braking direction.
Tests have however shown that the spike movements during a traction maneuver
differ from the
spike movements during a braking maneuver. It is therefore desirable for the
different movement
processes under the different loads to also be better taken into consideration
in the configuration
of the spike design, and for the spike performance to be improved.
CA 3029771 2019-03-07
2
EP 2 540 527 Al has disclosed vehicle tires with rotationally asymmetrical
spikes, in the case of
which, in the spike pin, the grip edge in front in a traction direction is
formed with portions
converging on one another in tapering fashion and the grip edge in front in a
braking direction is
formed with concave portion. In this way, the grip action in the traction and
braking directions
differ owing to the grip edge differences.
Here, the spike used from EP 2 540 527 Al is, in all portions along its
extent, that is to say in the
foot flange and also in the central part of the spike body and in the top
flange and in the tip of the
spike pin, formed with a complex varying triangular design, wherein here, the
individual portions
are in each case arranged offset with respect to one another such that their
respective centers of
gravity are likewise all positioned offset with respect to one another. The
distance between the
overall center of gravity axis of the overall spike and that edge of the spike
foot which is in front
in the direction of rotation during forward travel is in this case configured
to be much larger than
the distance between the rear extent edge of the spike foot and the overall
center of gravity axis.
The complex three-dimensional structure is intended here to ensure the
purchase of the spike
during braking and traction maneuvers. The complex triangular design in all
parts of the spike
such as foot flange, central part, top flange and spike tip involves great
outlay to produce.
Furthermore, the complex body shape is very non-uniform after the installation
of the spike into
the surrounding rubber matrix of the tire, whereby stress peaks are induced
therein. This can lead
to a reduction of purchase forces owing to relatively severe creep processes
in the rubber and to
an inducement of cracks in the rubber and, in the long term, to loss of the
spike. The stability of
the spike in the profile, and the functional reliability thereof, are impaired
as a result. The non-
uniform stress situation in the rubber matrix is also disadvantageous if, in
particular cases, it is
the intention for the spike to be vulcanized in the rubber matrix by means of
an adhesion
promoter.
SUMMARY
The invention is therefore based on the object of making it possible to
realize such vehicle tires
with spikes in the case of which different conditions during braking and
traction operations are
made possible more reliably and more easily with easy processability.
CA 3029771 2019-03-07
3
The object is achieved according to the invention by means of the embodiment
of a directional
vehicle tire having a tread profile and having spikes which are composed of a
spike body and of
a spike pin. According to a broad aspect, the invention provides a directional
vehicle tire
comprising a tread profile and spikes which are composed of a spike body and
of a spike pin,
wherein the spike pin with an encircling grip edge which forms a grip edge
situated in front in a
direction of rotation during forward travel and a grip edge situated behind in
the direction of
rotation, which grip edges each extend over an entire width, formed in an
axial direction of the
tire, of the spike pin, wherein a first grip edge length, effective in a
circumferential direction of
the tire, of the encircling grip edge is greater than a second grip edge
length effective in the axial
direction, wherein the grip edge situated in front in the direction of
rotation during forward travel
is formed in the direction of rotation with two grip edge portions converging
on one another in
tapering fashion, wherein the spike body is formed from a foot flange, a
central portion and a top
flange, wherein the top flange and the central portion are formed in each case
with a circular,
oval or elliptical section contour in section planes formed perpendicular to a
longitudinal extent
of the spike, wherein a center of gravity of the spike pin, a center of
gravity of the top flange, a
center of gravity of the central portion and a center of gravity of the foot
flange are arranged on a
common straight line, and wherein, in the section planes formed perpendicular
to the
longitudinal extent direction of the spike, the foot flange is formed with a
section contour
wherein a point of the section contour which in the direction of rotation is
furthest remote from
the common straight line and situated in front of the common straight line is
arranged at a
distance a, measured in the direction of rotation, from the common straight
line, wherein a point
of the section contour which is furthest remote from the common straight line
and situated
behind the common straight line is arranged at a distance b, measured in the
direction of rotation,
from the straight line, wherein a 0 b.
According to embodiments of the invention, it is made possible that, in those
parts of the spike
which are particularly relevant specifically for traction and braking, the
differences important for
traction and braking are also allowed for, with a common center of gravity
axis of the various
spike portions. Thus, the grip edge of the spike pin in the traction and
braking direction during
forward travel is designed to be optimized in each case for the different
demands for braking and
CA 3029771 2019-03-07
4
. traction, such that the front edge important for the traction can easily
penetrate into ice and chip
the latter. The spike body, with its foot flange, makes it possible, by means
of the design with
distances b and a of different magnitude, for the bedding stiffness of the
spike to differ for
traction and braking. Since the conditions for traction and braking are
different, it is possible by
means of the different bedding stiffness for both traction and braking to be
optimized in
accordance with the individual requirements of the desired use of the tire.
Here, the selection of
the length ratio of the lengths a and b makes it possible to targetedly
realize a greater bedding
stiffness of the spike allowing for the slip to be expected during the planned
use of the tire for
traction or braking. Here, the design of the central part and of the top
flange with a simple
geometrical structure and the common center of gravity axis of the various
spike portions permit
both reliable and simple production of the spike without complex undercuts,
and also the
introduction of the spike into the tire, and also reliable vulcanization onto
the surrounding rubber
matrix. The stability and functionality can be improved in this way.
In one embodiment, a>b. In this way, it is made possible for the spike to
exhibit spike bedding
with increased flexibility during launch and traction movements with high
slip. In this way,
stress peaks between the front flank of the spike tip in the direction of
rotation and the ice surface
are depleted. In this way, the spike duly penetrates into the ice. After the
penetration, it is then
possible, without further destruction of the ice, for traction forces to be
more quickly and reliably
transmitted by interlocking of the front flank of the spike tip with the ice.
The traction is thus
improved. This has a particularly advantageous effect specifically in the case
of use with
electronic anti-slip regulation. In the case of electronic anti-slip
regulation systems, the wheel
rotational speed differences are used to calculate the slip states. In
particular during launch or
traction operations, the determined wheel speeds are rather inaccurate owing
to the low vehicle
speed, and the estimation of the slip states are consequently also somewhat
inaccurate.
Furthermore, the regulation chain relating to the engine torque is slow and
somewhat inert. This
has the result that the degrees of relative slip are particularly high in
particular at the start of the
launch process. Thus, specifically in the case of use with electronic drive
regulation, the
embodiment with its faster and more reliable transmission of the traction
forces is particularly
advantageous. Here, the embodiment also permits a particular boost of the
braking forces
transmitted via the spike, because, owing to the long dimensioning of "a", a
large lever arm is
CA 3029771 2019-03-07
5
realized, and thus large tilting moments can be transmitted. This has a
particularly advantageous
effect specifically in the case of use with electronic anti-slip regulation.
In the case of
electronically assisted and regulated braking maneuvers, the determined real
rotational speeds
are relatively accurate in a first brake-applying cycle with high slip, and,
owing to fast reaction
-- capability of the brake system, make it possible for the occurring slip
states to be reduced to a
minimum in an effective manner. Therefore, the relatively stiff spike bedding
of the embodiment
under this loading is particularly advantageous. The embodiment is thus highly
effective
specifically in conjunction with electronic anti-slip regulation.
1() -- In one embodiment, a<b. In this way, traction and braking
characteristics on ice can be improved
during use without electronic anti-slip regulation and without anti-lock
system. In the case of this
use, the slip is relatively low during traction and is high during unregulated
braking effected
purely by the vehicle driver. The embodiment with a relatively large distance
b makes it possible
for spike bedding with increased flexibility to be achieved during braking
with high slip. The
-- braking forces can thus be transmitted more effectively. Furthermore, the
tilting actions during
traction can be reliably counteracted, and the spike can engage with its tips
at the front grip edge
of the spike tip into the ice in optimum fashion. This embodiment is
particularly advantageous
specifically in the case of use on vehicles without electronic anti-slip
regulation. When driving
without electronic anti-slip regulation, the driver seeks from the outset to
avoid conditions of
-- high slip and an unsafe driving state during launching through careful
application of the throttle
and slow "slipping engagement" of the clutch. In emergency stop situations,
the driver actuates
the brake pedal with maximum force. Here, if the adhesion friction limit is
overshot, the wheels
lock and high slip occurs. The embodiment thus permits an optimization
allowing for the large
slip movements during braking during driving without electronic anti-slip
regulation, and the
-- small slip movements during traction during launching.
In one embodiment, that grip edge of the spike pin which is situated behind in
the direction of
rotation includes one or more curved portion(s). In a further embodiment, the
one or more curved
portion(s) are convexly curved. In another further embodiment, the one or more
curved
-- portion(s) are concavely curved. In one embodiment, that grip edge of the
spike pin which is
situated behind in the direction of rotation includes one or more
rectilinearly extending
CA 3029771 2019-03-07
6
=
portion(s). These permit, in a simple manner, a large effective overall length
of the grip edge
situated behind, with high stability. The grip edge situated behind plays a
particular role in the
transmission of braking forces. Particularly high braking forces can be
transmitted in the case of
low tyre slip. It is therefore desirable for the grip edges situated behind to
be formed with a large
-- overall length in order to ensure the greatest possible support in the
interlocking with the ice
surface. The embodiment with curved grip edge portions makes it possible here,
despite a
particularly large effective overall length, to avoid edge transitions
converging in tapering
fashion, and possible breakaway tendencies, in the sensitive grip edge region
situated behind. In
this way, it is however possible to produce spike pins with a large effective
edge length but with
-- reduced volume and spike weight. In this way, road wear can be reduced,
without adversely
affecting the important winter characteristics.
In one embodiment, in the section planes formed perpendicular to the
longitudinal extent
direction of the spike, the foot flange is delimited, at a distance a from the
common straight line
-- and in front of the common straight line, by a rectilinearly extending
extent portion, and,
between said rectilinearly extending extent portion and that point of the
section contour which is
situated behind the common straight line and at a distance b from the common
straight line, a
with a circular-segment-shaped, oval-segment-shaped or ellipse-segment-shaped
section contour
are formed, wherein the relatively long main axis of the oval or of the
ellipse is oriented in the
-- circumferential direction U of the tire. By means of this embodiment, it is
possible in a simple
mariner to optimize the bedding stiffness and the lever ratios at the spike
foot for the occurring
slip movements during driving without electronic anti-slip regulation, and to
achieve a uniform
contact pressure of the surrounding rubber matrix on the spike body for the
attachment by
vulcanization.
In one embodiment, in the section planes formed perpendicular to the
longitudinal extent
direction of the spike, the foot flange is delimited, at a distance b from the
common straight line
g and behind the common straight line g, by a rectilinearly extending extent
portion, and,
between said rectilinearly extending extent portion and that point of the
section contour which is
-- situated in front of the common straight line g and at a distance a from
the common straight line
g, a with a circular-segment-shaped, oval-segment-shaped or ellipse-segment-
shaped section
CA 3029771 2019-03-07
7
. contour are formed, wherein the relatively long main axis of the oval or
of the ellipse is oriented
in the circumferential direction U of the tire. By means of this embodiment,
it is possible in a
simple manner to optimize the bedding stiffness and the lever ratios at the
spike foot for the
occurring slip movements during driving with electronic anti-slip regulation
with large slip
movements during traction and small slip movements during braking, and to
achieve a uniform
contact pressure of the surrounding rubber matrix on the spike body for the
attachment by
vulcanization.
In one embodiment, the grip edge situated in front in the direction of
rotation during forward
travel is formed in the direction of rotation with two rectilinearly extending
grip edge portions
converging on one another in tapering fashion, wherein a central,
rectilinearly extending grip
edge portion is formed between the two grip edge portions converging on one
another in tapering
fashion, wherein that extent end of one of the two grip edge portions
converging on one another
in tapering fashion which is situated in front in the direction of rotation
transitions, with the
formation of a bend, into one extent end of the central grip edge portion, and
wherein that extent
end of the other of the two grip edge portions converging on one another in
tapering fashion
which is situated in front in the direction of rotation transitions, with the
formation of a bend,
into the other extent end of the central grip edge portion. The design of the
grip edge situated in
front has a particular influence both on the grip characteristics and on road
wear. It must be able
to reliably penetrate into the ice surface, because the spike otherwise cannot
mechanically
interlock. The two grip edge portions converging in tapering fashion permits
an effective
penetration of the grip edge into the ice in a simple manner, because the
effective edge length
that impinges as the tire rolls can be reduced to the length of the central
grip edge portion. The
central grip edge portion permits, upon the penetration into the ice surface,
a corresponding
interlocking face surface for good winter grip. Here, it is also ensured that
the spike pin does not
impinge on the road surface in punctiform fashion, but rather rolls over the
edge of the central
grip portion, whereby the wear of the road surface can be reduced.
In one embodiment, the central grip edge portion is oriented to extend in the
axial direction of
the tyre. During the transmission of forces, the resultant force is always
perpendicular to the
spike pin surface, but only the component pointing in the circumferential
direction can be
CA 3029771 2019-03-07
8
=
, utilized for the transmission of braking or traction forces. The force
vectors pointing in another
direction generate reactive stresses in the ice, which can lead to
''premature" ice fracture and thus
to a reduced transmission of force by interlocking. This embodiment of the
central portion
permits an optimization of the winter characteristics, because all force
vectors in the central grip
edge portion point in the circumferential direction, and thus the occurrence
of reactive forces is
prevented.
In one embodiment, that grip edge of the spike pin which is situated behind in
the direction of
rotation is formed with two rectilinearly extending grip edge portions
converging on one another
in tapering fashion counter to the direction of rotation and with a central,
concavely curved grip
edge portion formed between the two grip edge portions converging on one
another in tapering
fashion, wherein that extent end of one of the two grip edge portions
converging on one another
in tapering fashion which is situated behind in the direction of rotation
transitions, with the
formation of a bend, into one extent end of the central grip edge portion, and
wherein that extent
end of the other of the two grip edge portions converging on one another in
tapering fashion
which is situated behind in the direction of rotation transitions, with the
formation of a bend, into
the other extent end of the central grip edge portion. The embodiment permits,
in a simple
manner, a large effective overall length of the grip edge situated behind,
with high stability. The
grip edge situated behind plays a particular role in the transmission of
braking forces.
Particularly high braking forces can be transmitted in the case of low tyre
slip. It is therefore
desirable for the group edges situated behind to be formed with a large
overall length in order to
ensure the greatest possible support in the interlocking with the ice surface.
The embodiment
with the central grip edge portion makes it possible here, despite a large
effective overall length,
to avoid edge transitions converging in tapering fashion, and possible
breakaway tendencies, in
the sensitive grip edge region situated behind.
In one embodiment, the encircling grip edge forms in each case one lateral
grip edge to both
sides in the axial direction, wherein the lateral grip edge has in each case
one extended portion in
which the grip edge is oriented so as to extend rectilinearly in the
circumferential direction U of
the tire. The lateral control can be additionally further promoted in this
way.
CA 3029771 2019-03-07
9
. BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be discussed in more detail below on the basis of the
exemplary embodiments
illustrated in figures 1 to 11. In the figures:
figure 1 shows a circumferential portion of a pneumatic vehicle tire
with spikes in plan
view,
figure 2 shows an enlarged illustration of a spike of the tread profile
of figure 1 in plan
view,
figure 3 shows the spike of figure 2 in a side view in the viewing
direction III-111 of figure
2,
figure 4 shows the spike of figure 2 in another side view in the viewing
direction IV-IV of
figure 2,
figure 5 shows the spike of figure 2 in another side view in the viewing
direction V-V of
figure 2,
figure 6 shows the spike of figure 2 in a perspective illustration,
figure 7 shows an enlarged illustration of the spike of figure 2 in an
alternative
embodiment,
figure 8 shows the spike of figure 7 in a side view in the viewing
direction VIII-VIII of
figure 7,
figure 9 shows the spike of figure 7 in another side view in the
viewing direction IX-IX
of figure 7,
figure 10 shows the spike of figure 7 in another side view in the
viewing direction X-X of
figure 7, and
figure 11 shows the spike of figure 7 in a perspective illustration.
DETAILED DESCRIPTION OF EMBODIMENTS
Variants, examples and preferred embodiments of the invention are described
hereinbelow.
Figure 1 shows a tread profile of a directional pneumatic vehicle tire for
passenger motor vehicle
tires with winter characteristics, having multiple profile block rows 22, 23,
24, 25 and 26 of
CA 3029771 2019-03-07
10
known type arranged adjacent to one another in an axial direction A of the
pneumatic vehicle
=
tire. The profile block row 22 is, in a known manner, oriented so as to extend
in a circumferential
direction U over the entire circumference of the pneumatic vehicle tire, and
formed from profile
block elements which are arranged one behind the other in the circumferential
direction U of the
pneumatic vehicle tire and which are separated from one another by transverse
channels 31.
Likewise, the profile block row 23, the profile block row 24 and the profile
block row 25 are
each oriented so as to extend in the circumferential direction U over the
entire circumference of
the pneumatic vehicle tire, and formed in a known manner from profile block
elements which are
arranged one behind the other in the circumferential direction U and which are
in each case
separated from one another by transverse channels 31. Likewise, the profile
block row 26 is
oriented so as to extend in the circumferential direction U over the entire
circumference of the
pneumatic vehicle tire, and formed in a known manner from profile block
elements which are
arranged one behind the other in the circumferential direction U and which are
in each case
separated from one another by transverse channels 31. The profile block rows
22 and 26 are
shoulder profile block rows. The profile block rows 23, 24 and 25 are formed
in the central
extent portion of the profile. The profile block elements of the profile block
row 22 and the
adjacent profile block elements of the profile block row 23 are formed so as
to be separated from
one another in an axial direction A by circumferential channels 27 of known
type extending in
the circumferential direction U. The profile block elements of the
CA 3029771 2019-03-07
CA 03029771 2019-01-03
11
profile block row 23 and the adjacent profile block elements of the profile
block row 24 are
formed so as to be separated from one another in the axial direction A by
circumferential
channels 28, The profile block elements of the profile block row 24 and the
adjacent
profile block elements of the profile block row 25 are arranged so as to be
separated from
-- one another in the axial direction A by circumferential channels 29. The
profile block
elements of the profile block row 25 and the adjacent profile block elements
of the profile
block row 26 are arranged so as to be separated from one another in the axial
direction A
by circumferential channels 30.
-- The transverse channels 31 extend in a V shape over the entire axial extent
region of the
tread profile, through the tread profile from the profile block row 22 formed
in the left-
hand shoulder to the profile block row 26 formed in the right-hand shoulder.
The direction of rotation D of the pneumatic vehicle tire during forward
travel is indicated
in figure 1 and figure 2.
In the profile block rows 22, 23, 25 and 26, in each case in a manner
distributed over the
circumference in different profile block elements, spikes 1 are fastened spike
holes of
known type, which in a known manner are formed in the profile block elements
for the
purposes of receiving the spikes I.
Figure 2 shows the illustration of a spike I in an enlarged illustration and,
for the purposes
of a simplified illustration, without the surrounding rubber material of the
pneumatic
vehicle tire. As illustrated in figures 2 to 6, the spike 1 is in a known
manner formed from
-- a spike body 2 and from a spike pin 3. The spike body 2 is, from the inside
outward as
viewed in the radial direction R of the pneumatic vehicle tire, formed in a
known manner
from a foot flange 4, a waisted central part 5 adjoining said foot flange, and
a top flange 6
adjoining said central part. The spike body 2 is formed with a height H in the
radial
direction R of the pneumatic vehicle tire.
CA 03029771 2019-01-03
12
Here, the top flange 6 extends in the radial direction R of the pneumatic
vehicle tire over
an extent height H3 of Omm < H3 < (0.92 H), and is formed with a cylindrical
shell surface
with a cylinder diameter D3. At the transition outward in the radial direction
R of the tire to
the face surface of the spike body 2 and inward to the waisted central part 5,
the top flange
6 is beveled concentrically with respect to the cylinder axis. In the case of
conventional
passenger motor vehicle or van tires, the extent height H3 is selected to be
(0.25H) < H3 <
(0.48 H).
The foot flange 4 is formed with an extent height HI extending in the radial
direction R of
the pneumatic vehicle tire, where (0.08 H) < < (0.4 H). In the case of
conventional
passenger motor vehicle or van tires, the extent height Hi is selected to be
(0.1 H) <Iii<
(0.2 H).
The foot flange 4 is formed with a cylindrical shell surface composed of a
shell surface
portion 18 and a shell surface portion 19, wherein the shell surface portion
18 forms the
segment of a cylinder shell surface with cylinder axis and diameter DI, and
the shell
surface portion 19 forms a planar surface which intersects the imaginary
completed
cylinder shell surface of the segment parallel to the cylinder axis.
As can be seen in figure 2 and figure 5, in the section planes perpendicular
to the main
extent direction of the spike 1 and thus perpendicular to the radial extent
direction R of the
tire, the shell surface portion 19 is formed so as to extend rectilinearly,
and the portion 18
is in the shape of a circular segment. The shell surface portion 19 and thus
the rectilinear
section contour lines are, in the direction of rotation D, positioned in front
of the position
of the center of mass Si of the foot flange 18 at a distance a from the
position of the center
of mass Si. The cylinder-segment-shaped shell portion 18 and thus the circular-
segment-
shaped section contour line extend counter to the direction of rotation D as
far as into a
position at a distance b from the center of mass Si of the foot flange 4.
Here, the distances
b and a are configured such that b > a. Likewise, (a + b) <D1.
CA 03029771 2019-01-03
13
As can be seen in figures 3 to 6, the foot flange 4 is also of beveled form at
its transition to
the face surface that delimits the spike body 2 inward in the radial direction
R of the tire.
The central part 5 of the spike body 2 is, in a known manner, of waisted form,
and extends
over an extent height H2 measured in the longitudinal extent direction of the
spike 1 and
thus in the radial direction R of the tire, where Omm < H2 < (0.92 H). In the
case of
conventional passenger motor vehicle or van tires, the extent height H2 is
selected to be
(0.4H) H25. (0.55 H).
In all cross-sectional planes perpendicular to the main extent direction of
the spike 1 and
thus to the radial extent direction R of the tire, the central part 5 is
formed with a circular
section contour of its shell surface. Here, proceeding from the diameter D3 at
the position
of the transition to the top flange 6, the diameter of the circular section
contours becomes
continuously smaller along the extent of the spike 1 in the direction of the
foot flange 4
until a minimum value D2 is reached, and after said minimum value has been
reached, said
diameter becomes continuously larger as far as the transition to the foot
flange 4.
In the face surface that delimits the spike body 2 outward in the radial
direction R of the
tire at its top flange 6, there is formed, in a known manner, an opening for
receiving and
for the fastening of the spike pin 3, in which opening the spike pin is
fastened when in the
installed state in the pneumatic vehicle tire. The spike in 3 extends in the
tire, from the face
surface that forms a delimitation radially outward at the top flange 6 of the
spike body 2,
further outward in the radial direction R of the pneumatic vehicle tire, and
forms the spike
tip here. The spike tip and thus the spike pin 3 is delimited outward in the
radial direction
R of the tire with a surface that forms a plateau 20. The transition between
the shell surface
of the spike pin 3 and the plateau 20 has a sharp edge, and here forms a grip
edge 7
running in encircling fashion around the spike pin 3. A radial elevation 21
extends outward
in the radial direction R out of the plateau 20 at a distance from the grip
edge 7 in a known
manner, which elevation can facilitate the rolling movement.
The encircling grip edge 7 is formed, with a at its extent section situated in
front in the
direction of rotation D during forward travel, with a grip edge 8 situated in
front, and at its
CA 03029771 2019-01-03
14
extent section situated behind in the direction of rotation D during forward
travel, with a
grip edge 9 situated behind, and with grip edge portions 16 and 17 which
delimit the spike
pin 3 in the axial direction A of the pneumatic vehicle tire, which grip edge
portions are
each oriented so as to extend in the circumferential direction U of the
pneumatic vehicle
tyre.
The grip edge 8 situated in front is formed from two lateral, in each case
rectilinearly
extending grip edge portions 10 and 12, and from a central extent portion 11
which is
arranged in the axial direction A of the pneumatic vehicle tire between the
two lateral grip
edge portions 10 and 12. The lateral, rectilinear grip edge portions 10 and 12
are in this
case formed so as to be oriented so as to converge on one another in tapered
fashion in V-
shaped or arrow-shaped form as viewed in the direction of rotation D. The
central extent
portion 11 is formed so as to be oriented so as to extend rectilinearly in the
axial direction
A of the pneumatic vehicle tire. Here, that extent end of the lateral grip
edge portion 10
which is situated at the front as viewed in the direction of rotation D forms
one extent end,
directed toward the grip edge portion 10, of the central extent portion 11,
and transitions
there, with the inclusion of a bend in the extent profile of the grip edge 8
situated in front,
and thus of the encircling grip edge 7, into the central extent portion 11.
Likewise, the front
extent end, directed in the direction of rotation D, of the lateral grip edge
portion 12 forms
that extent end of the central extent portion 11 which is directed toward the
lateral extent
portion 12, and transitions there, with the inclusion of a bend in the extent
profile of the
grip edge 8 situated in front, and thus of the encircling grip edge 7, into
the central extent
portion 1 1 .
That extent end of the lateral grip edge portion 10 which is situated at the
rear as viewed in
the direction of rotation D forms that extent end of the grip edge portion 16
which is
situated at the front as viewed in the direction of rotation D, and
transitions, with the
inclusion of a bend in the extent profile of the encircling grip edge 7, into
the grip edge
portion 16. Likewise, that extent end of the lateral grip edge portion 12
which is situated at
the rear as viewed in the direction of rotation D forms that end of the grip
edge portion 17
which is situated at the front in the direction of rotation D, and transitions
there, with the
CA 03029771 2019-01-03
inclusion of a bend in the extent profile of the encircling grip edge 7, into
the grip edge
portion 17.
The grip edge 9 situated behind in the direction of rotation D is formed from
two lateral
5 extending grip edge portions 13 and 15 and from a central extent portion
14 which is
arranged in the axial direction A of the pneumatic vehicle tire between the
two lateral grip
edge portions 13 and 15. The lateral grip edge portions 13 and 15 are formed
so as to
extend rectilinearly and so as to be oriented so as to converge on one another
in tapered
fashion in V-shaped or arrow-shaped form as viewed in the direction of
rotation D. The
10 central extent portion 14 is formed with a concavely curved curvature
profile, that is to say
the curvature radius of the curvature profile 14 is formed on that side of the
curvature line
which points away from the spike pin 3.
That extent end of the lateral grip edge portion 13 which is formed behind in
the direction
15 .. of rotation D forms that extent end of the grip edge portion 14 which is
formed toward the
grip edge portion 13, and transitions there, with the inclusion of a bend in
the extent profile
of the rear grip edge 9, and thus of the encircling grip edge 7, into the
extent portion 14.
That extent end of the lateral grip edge portion 15 which is formed behind in
the direction
of rotation D forms that extent end of the grip edge portion 14 which is
formed toward the
grip edge portion 15, and transitions there, with the inclusion of a bend in
the extent profile
of the rear grip edge 9, and thus of the encircling grip edge 7, into the
extent portion 14.
That extent end of the grip edge portion 13 which is situated in front in the
direction of
rotation D forms that extent end of the grip edge portion 16 which is situated
behind in the
direction of rotation D, and transitions there, with the inclusion of a bend
in the extent
profile of the encircling grip edge 7, into the grip edge portion 16. That
extent end of the
grip edge portion 15 which is situated in front in the direction of rotation D
forms that
extent end of the grip edge portion 17 which is situated behind in the
direction of rotation
D, and transitions there, with the inclusion of a bend in the extent profile
of the encircling
grip edge 7, into the grip edge portion 17.
CA 03029771 2019-01-03
16
The projection of the encircling gip edge 7 in the axial direction A of the
tire has a
projection length e. The projection of the encircling grip edge 7 in the
circumferential
direction U of the tire has a projection length c, which corresponds to the
width of the
spike pin 3 at the radial position of the grip edge 7 and indicates the
effective grip edge
length of the spike 1 in the circumferential direction U. The projection
length e
corresponds to the extent length, measured in the circumferential direction U,
of the spike
pin 3 at the radial position of the grip edge 7, and indicates the effective
grip edge length of
the spike in the axial direction A of the tire. Here, c and e are dimensioned
such that c> e.
The extent length, measured in the axial direction, of the central extent
portion 11 of the
front grip edge 8 is in this case configured in the range from 40% to 80% of
the projection
length c. The extent length, measured in the axial direction A, of the central
extent portion
14 of the rear grip edge 9 is in this case configured to be greater than the
extent length,
measured in the axial direction A, of the central extent portion 11 of the
front grip edge 8.
As illustrated in figures 3, 5 and 2, the center of mass S1 of the foot flange
4 of the spike
body 2, the center of mass S2 of the central part 5 of the spiked body 2, the
center of mass
S3 of the top flange 6 and the center of mass S4 of the spike pin 3 lie on a
common straight
line g, which extends in the radial direction R of the pneumatic vehicle tire.
The overall
center of mass S (not shown) of the spike I also lies on said straight line.
In the exemplary embodiments described and illustrated in the figures, the
central part 5
and the top flange 6 are, in terms of their shell surface, in each case of
circular form in the
section planes perpendicular to the main extent direction of the spike and to
the radial
extent direction R of the tire.
In another embodiment which is not illustrated, the section contours of the
shell surfaces of
top flange 6 and of central part 5 are each of oval or elliptical form,
wherein the relatively
large main axis of the oval or of the ellipse is oriented in the
circumferential direction U of
the pneumatic vehicle tire. The above-stated diameters D2 and D3 then in each
case form
the relatively large diameter of the respective ellipse or of the oval.
CA 03029771 2019-01-03
17
In the exemplary embodiments described above and illustrated in the figures,
the foot
flange is of cylinder-segment-shaped form in the region of its shell surface
portion 18, with
a circular outline of the cylinder and with a circular-segment-shaped section
line contour of
the cylinder segment shape in the section planes perpendicular to the main
extent direction
of the spike 1 and to the radial extent direction R of the tire.
In an alternative embodiment which is not illustrated, the shell surface
portion 18 is a
cylinder-segment-shaped portion with an oval or elliptical outline of the
cylinder and with
an oval-segment-shaped or ellipse-segment-shaped section line contour of the
cylinder
segment shape in the section planes perpendicular to the main extent direction
of the spike
1 and to the radial extent direction R of the tire, wherein the relatively
large main axis of
the ellipse or of the oval is oriented in the circumferential extent direction
U of the
pneumatic vehicle tire. The above-stated diameter Di then corresponds to the
relatively
large diameter of the oval or of the ellipse.
Figures 7 to 11 illustrate a spike 1 of an alternative embodiment, which is
designed
similarly to the spike 1 illustrated in figures 2 to 6 and described above.
Only the foot
flange 4' of the spike body 2 is designed to be rotated through 1800 about the
straight line g
in relation to the spike illustrated in figures 2 to 8 and described above.
The shell surface
portion 19 and thus the rectilinear section contour lines are, in the
direction of rotation D of
the pneumatic vehicle tire, positioned behind the position of the center of
mass S1 of the
foot flange 4 at a distance b from the straight line g and from the position
of the center of
mass SI. The cylinder-segment-shaped shell portion 18 and thus the circular-
segment-
shaped section contour line extend in the direction of rotation D as far as
into a position at
a distance a in front of the straight line and the center of mass Si of the
foot flange 4. Here,
the distances b and a are configured such that b <a. In this embodiment, too,
(a + b) < Di
applies.
18
=
, LIST OF REFERENCE DESIGNATIONS
(Part of the description)
1 Spike
2 Spike body
3 Spike pin
4 Foot flange
5 Waisted central portion
6 Top flange
7 Encircling grip edge
8 Grip edge situated in front
9 Grip edge situated behind
10 Grip edge portion
11 Central grip edge portion
12 Grip edge portion
13 Grip edge portion
14 Central grip edge portion
15 Grip edge portion
16 Grip edge portion
17 Grip edge portion
18 Shell contour portion
19 Shell contour portion
20 Plateau
21 Elevation
22 Profile block row
23 Profile block row
24 Profile block row
25 Profile block row
26 Profile block row
27 Circumferential channel
CA 3029771 2019-03-07
CA 03029771 2019-01-03
19
28 Circumferential channel
29 Circumferential channel
30 Circumferential channel
31 Transverse channel
32 Sipe
