Note: Descriptions are shown in the official language in which they were submitted.
CA 02732197 2012-11-27
74476-7
1
Chain Pad for a Chain Link
The invention relates to a chain pad with a base unit having a floor plate,
and with a pad unit connected with the base unit on an interior side of the
floor plate, wherein the base unit has a number of engaging elements
on the interior side of the floor plate that are raised above the interior
side, which together with the pad unit establish a positive connec-
tion.
10,
Such chain pads are known from EP 0 953 498 Al, as well as from
DE 26 906 Al, US 6,412,888 BI and GB 2360750 A. The previously
known chain pads for a chain link have a base unit with a floor plate
designed as sectionally angled sheet metal. In addition, the chain
pads are equipped with a pad unit consisting of a rubber material
typically applied to an interior side of the floor plate through vulcani-
zation to establish a non-positive connection. The previously known
chain pads are designed for insertion into a chain link of a caterpillar
tread for a crawler vehicle. In addition, the base unit of these previ-
ously known chain pads has a number of engaging elements on the
interior side of the floor plate that are raised above the interior side,
which together with the pad unit establish a positive connection.
However, this does not ensure with sufficient reliability that the pre-
viously known chain pads can withstand the high loads typically en-
countered in caterpillar treads under all conceivable conditions, since
while the force is absorbed to a significant extent by the positive
connection, the latter is not always enough given at least a sectional
failure of a non-positive connection established 'through vulcaniza-
tion.
Therefore, some embodiments of the invention may indicate a chain pad of the
kind mentioned at the outset characterized by an even more stable
CA 02732197 2012-11-27
74476-7
2
connection between the base unit and pad unit while being easy to manufacture
by
comparison to the previously known chain pads.
Some embodiments disclosed herein relate to a chain pad for a chain link with
a base
body consisting of interconnected floor plate, and also connected with a
number of
engaging elements on the interior side of the floor plate with engaging
recesses provided
with webs, as well as a pad unit connected on the interior side of the base
unit, wherein
the engaging recesses establish a positive connection with the pad unit,
wherein a cover
strip is arranged on each exterior side of each web at a distance from the
interior side of
the floor plate as another engaging element, and wherein the base unit
consists of metal
or a high-strength composite material or plastic, and the pad unit consists of
hard rubber,
polyurethane, rubber mixtures and/or elastic composite or plastic.
The chain pad may surprisingly satisfy the mentioned stringent requirements
placed on
chain pads used for caterpillar treads by virtue of the fact that the base
unit has cover
strips extending in the longitudinal direction and spaced apart from the
longitudinal side
edges of the floor plate, the exterior sides of which accommodate spaced apart
guide
strip sections, and that a latching tongue projecting at an inclination toward
the
transverse side edge of the floor plate is provided in the end region on the
exterior side
of the floor plate opposite the interior side, wherein the latching tongue
preferably
undulates in such a way as to have two curved tongue edge sections facing away
from
the exterior side of the floor plate, and a tongue midsection curved
oppositely toward the
floor plate and arranged between the tongue edge sections. This configuration
may
make the latching tongue highly resistant to inward bending toward the floor
plate.
Another configuration of the latching tongue may enable a simple removal of
the chain
pad from the chain link during maintenance or replacement by providing the
latching
tongue with flat tongue edge sections on either side of a tongue midsection
curved
inward toward the floor plate like a trough, which may lead to a relatively
simple
deformability, and hence an easy detachment of the rear grip of the latching
tongue with
the tongue stop.
CA 02732197 2011-01-27
74476-7
3
Additional expedient embodiments and advantages to the invention
may be gleaned from the following description of exemplary em-
bodiments with reference to the figures in the drawing. Shown on:
Fig. 1 is a perspective view of an exemplary embodiment of a
chain pad according to the invention and a chain link,
Fig. 2 is a perspective view of the chain pad and the chain link
according to Fig. 1, pre-assembly configuration.
Fig. 3 is a perspective view of the chain pad and the chain link
according to Fig. 1 and Fig. 2, final assembly configura-
tion.
Fig. 4 is a perspective view of a configuration of a base unit of
a chain pad according to the invention, which is pro-
vided with webs extending in the transverse direction,
Fig. 5 is a longitudinal section of the exemplary embodiment of
a chain pad according to Fig. 1,
Fig. 6 is a cross section between webs depicting the exem-
plary embodiment of a chain pad described in the inven-
tion according to Fig. 1,
Fig. 7 is a cross section through a web depicting the exem-
plary embodiment of a chain pad described in the inven-
tion according to Fig. 1,
Fig. 8 is a perspective view of another exemplary embodiment
of a chain pad according to the invention,
CA 02732197 2011-01-27
74476-7
4
Fig. 9 is a front view of a first configuration of a latching tongue
on a floor plate of a chain pad according to the inven-
tion.
Fig. 10 is a front view of another configuration of a latching
tongue on a floor plate of a chain pad according to the
invention.
Fig. 1 shows a perspective view of an exemplary embodiment of a
chain pad 1 according to the invention. The square chain pad 1 has
a pad unit 2 consisting of an elastic material, such as hard rubber,
polyurethane or an elastic composite or plastic, as well as a base
unit 3 consisting of a metal or high-strength composite material or
plastic. The base unit 3 having a basic rectangular shape is provided
with a floor plate 4, the interior side of which facing away from the
observer accommodates the pad unit 2 in the drawing according to
Fig. 1. The base unit 3 further has cover strips 5, 6 extending in the
longitudinal direction of the base unit 3 and spaced apart from the
longitudinal side edges of the floor plate 4, the exterior sides of
which in the exemplary embodiment according to Fig. 1 accommo-
date spaced apart guide strip sections 7, 8, 9, 10. A latching tongue
11 projecting at an inclination toward the transverse side edge of the
floor plate 4 is provided in an end region on the exterior side of the
floor plate 4 opposite the interior side and facing the user in the
drawing according to Fig. 1.
Also shown on Fig. 1 is a chain link 12 for a caterpillar tread of a
crawler vehicle not depicted in its entirety on Fig. 1, which as an es-
sentially square, flat massive body is provided with connecting pins
13, 14 projecting in a longitudinal direction on a transverse side, and
wall sections 15, 16, 17, 18 extending in the longitudinal direction
that project over a cover side. The wall sections 15, 16, 17, 18 lying
on a longitudinal side are spaced apart from each other by a dis
CA 02732197 2011-01-27
74476-7
tance roughly corresponding to the length of the guide strip sections
8, 10 of the chain pad 1 facing away from the latching tongue 11.
Each wall section 15, 16, 17, 18 is provided with a guide groove 19
that extends in the longitudinal direction of the chain link 12 and is
5 designed to accommodate the guide strip sections 7, 8, 9, 10 or con-
tinuous guide strip 41. The end region of the chain link 12 adjacent
to the connecting pins 13, 14 is further equipped with a projecting
tongue stop 20.
Fig. 2 shows the chain pad 1 and pad unit 2 according to Fig. 1 in a
pre-assembly configuration, in which the guide strip sections 8, 10
facing away form the latching tongue 11 and not visible on Fig. 2 are
inserted between the wall sections 15, 16, 17, 18 of the chain link 12,
and all guide strip sections 7, 8, 9, 10 are aligned flush with the
guide grooves 19 of the wall sections 15, 16, 17, 18. This pre-
assembly configuration can be used to slide the chain pad 1 into the
chain link 12 in an insertion direction up to an assembly configura-
tion.
Fig. 3 shows the exemplary embodiment according to Fig. 1 and Fig.
2 in the assembly configuration, in which the chain pad 1 has been
completely inserted into the chain link 12. In the assembly configura-
tion, the guide strip sections 8, 10 previously arranged in gaps 21
formed between the wall sections 15, 16, 17, 18 and lying on the
front side viewed in the insertion direction, as well as the guide strip
sections 7, 9 lying on the back side viewed in the insertion direction,
have entered into the guide grooves 9, and the end of the chain pad
1 facing away from the connecting pins 13, 14 abuts the stop wall 22
of the chain link 12, while the latching tongue 11 not visible in the
view on Fig. 3 encompasses the tongue stop 20 from the back. This
secures the chain pad 1 in the longitudinal direction, both in and
against insertion direction.
CA 02732197 2011-01-27
74476-7
6
As may also be gleaned from the drawing according to Fig. 3, the
end of the pad unit 2 facing away from the latching tongue 11 not
visible on Fig. 3 is provided with an end recess 23.
Fig. 4 shows a perspective view of a configuration of the base unit 3
for a chain pad 1 according to the invention, for example as depicted
on Fig. 1 with a view of the interior side. The floor plate 4 has an es-
sentially flat, centrally located floor plate midsection 24 extending in
the longitudinal direction of the base unit 3, abutted on either side in
the direction of the longitudinal edges by a respective floor plate
transition section 25, 26. The floor plate transition sections 25, 26
are trough-like in design, and spaced apart relative to the floor plate
midsection 24 with their deepest area being a greater distance away
from the cover strips 5, 6 than the floor plate midsection 24. At the
edge sides of the floor plate transition sections 25, 26 facing away
from the floor plate midsection 24, floor plate edge sections 27, 28
opposing the cover strips 5, 6 at a distance are provided, the exterior
side of which lines up precisely with the cover strips 5, 6. As a result,
the floor plate 4 has a dual undulating basic shape, in which the floor
plate midsection 24 and floor plate edge sections 27, 28 lie essen-
tially in one plane, and the floor plate transition sections 25, 26 each
form a trough extending in the longitudinal direction.
The floor plate midsection 24 exhibits two channel recesses 29, 30
lying opposite the latching tongue 11 in this exemplary embodiment,
which form an opening between the interior side facing the viewer in
the drawing according to Fig. 4 and the exterior side of the floor plate
4 facing away from the viewer in the drawing according to Fig. 4. A
midsection edge recess 31 is introduced in the floor plate midsection
24 on the transverse edge facing away from the latching tongue 11.
The base unit 3 of a chain pad 1 according to the invention has a
number of webs 32 aligned in a transverse direction, which are ar-
CA 02732197 2011-01-27
74476-7
7
ranged on the interior side of the floor plate 4 and elevated over the
floor plate 4. Each web 32 is provided with a centrally arranged web
midsection 33 and web edge sections 34, 35 arranged on either side
of the web midsection 33. Each web midsection 33 extends over the
floor plate midsection 24, while the web edge sections 34, 35 are
arranged in the area of the floor plate transition sections 25, 26. As
evident from Fig. 4, the middle of each web midsection 33 has a
minimal height over the floor plate midsection 24, while the height
increases toward the web edge sections 34, 35, peaking in the area
of the floor plate transition sections 25, 26. Respective engaging re-
cesses 36 that cross the webs 32 in a longitudinal direction are in-
corporated as engaging elements into the web edge sections 34, 35
in the configuration according to Fig. 4.
The cover strips 5, 6 are molded onto the ends of the web edge sec-
tions 34, 35 facing away from the web midsection 33 as additional
engaging elements, a distance away from the floor plate edge sec-
tions 27, 28, wherein the ends of the cover strips 5, 6 facing away
from the latching tongue 11 each have a startup incline 37 to facili-
tate the aforementioned insertion of the chain pad 1 into the chain
link 2.
Fig. 5 shows a longitudinal section of the chain pad 1 according to
Fig. 1. As evident from Fig. 5, the pad unit 2 completely envelops the
webs 32, wherein material enters the floor plate midsection 24 and
latching tongue 11 in a still free-flowing state while manufacturing the
pad unit 2, thereby forming a tongue underlay packing 38 for the
latching tongue 11 that increases resistance to constant deformation
that weakens the secure hold of the chain pad 1 in the chain link 12.
Fig. 6 shows the chain pad 1 according to Fig. 1 in a cross section
between two webs 32 not visible in the drawing according to Fig. 6.
As evident from Fig. 6, the material of the pad unit 2 forms a strip
CA 02732197 2011-01-27
74476-7
8
underlay packing 39 for the cover strips 5, 6 owing to the distance
between the cover strips 5, 6 and floor plate 4, so that the cover
strips 5, 6 are stabilized within the scope of elasticity of the material
comprising the pad unit 2, and held in place with a certain elasticity.
Fig. 7 shows a cross section of the chain pad 1 according to the ex-
emplary embodiment on Fig. 1, as a cross section through a web 32.
As evident from Fig. 7, the channel recesses 29, 30 incorporated into
the floor plate transition sections 25, 26 are filled with material of the
pad unit 2, thereby establishing additional positive connections be-
tween the pad unit 2 and base unit 3 distributed over the surface of
the base unit 3 to go along with the strip underlay packings 39.
Fig. 8 shows a perspective drawing of another exemplary embodi-
ment of a chain pad 1 according to the invention, wherein elements
in the exemplary embodiment according to Fig. 1 and the exemplary
embodiment according to Fig. 8 that correspond to each other are
provided with the same reference number, and will not be described
in any greater detail below. The exemplary embodiment according to
Fig. 8 has guide strips 40, 41 extending essentially over the entire
length of the cover strips 5, 6, which can be inserted into the guide
grooves 19 of a chain link 12 depicted on Fig. 1 to Fig. 3. Because
forces are introduced over the entire length of the cover strips 4, 6,
this exemplary embodiment is characterized by an especially high
stability.
The front view of a base unit 3 for a chain pad 1 according to the in-
vention shown on Fig. 9 depicts a first embodiment of a latching
tongue 11, which exhibits two curved tongue edge sections 42, 43
facing away from the exterior side of the floor plate 4, and a tongue
midsection 44 curved oppositely toward the floor plate 4 and ar-
ranged between the tongue edge sections 42, 43. This configuration
CA 02732197 2011-01-27
74476-7
9
of a latching tongue 11 is characterized by a very high resistance to
inward bending toward the floor plate 4.
The front view of a base unit 3 for a chain pad 1 according to the in-
vention shown on Fig. 10 depicts another embodiment of a latching
tongue 11, wherein flat tongue edge sections 46, 47 are in this con-
figuration provided on either side of a tongue midsection 45 curved
inward toward the floor plate 4 like a trough. This embodiment of a
latching tongue 11 is characterized by a relatively simple deform-
ability for detaching the rear grip of the latching tongue 11 with the
tongue stop 20 when removing the chain pad 1 from the chain link 2
during maintenance.
