U.S. patent application number 10/282068 was filed with the patent office on 2003-03-27 for radius conveyor belt with structure for the prevention of pinched fingers.
Invention is credited to Guldenfels, Dieter.
Application Number | 20030057061 10/282068 |
Document ID | / |
Family ID | 24315517 |
Filed Date | 2003-03-27 |
United States Patent
Application |
20030057061 |
Kind Code |
A1 |
Guldenfels, Dieter |
March 27, 2003 |
Radius conveyor belt with structure for the prevention of pinched
fingers
Abstract
A modular conveyor belt formed of rows of belt modules pivotally
interlinked by transverse pivot rods and specially adapted for
following a curved conveyor path. The modules include a top,
product conveying surface and a bottom, sprocket-driven surface.
The belt modules have a plurality of first link ends disposed in
the direction of travel of the conveyor belt and a plurality of
second link ends disposed in the opposite direction. Transverse
holes in the link ends are aligned to accommodate a pivot rod. When
the link ends of the consecutive rows of side by side modules are
intercalated, the pivot rod serves as a hinge pin in a hinged joint
between consecutive interlinked rows. To permit the belt to flex
sidewise, the openings in the first link ends are slotted
longitudinally in the direction of belt travel. In order to prevent
fingers from penetrating the grid, the belt modules have a
cross-rib with an extended portion in the longitudinal direction
designed so as to allow the link ends to undercut the cross-rib
when collapsing and to reduce the gap between adjacent modules.
Inventors: |
Guldenfels, Dieter;
(Pfeffingen, CH) |
Correspondence
Address: |
MCKENNA LONG & ALDRIDGE LLP
1900 K STREET, NW
WASHINGTON
DC
20006
US
|
Family ID: |
24315517 |
Appl. No.: |
10/282068 |
Filed: |
October 29, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10282068 |
Oct 29, 2002 |
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09874589 |
Jun 5, 2001 |
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09874589 |
Jun 5, 2001 |
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09579090 |
May 25, 2000 |
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6330941 |
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Current U.S.
Class: |
198/618 |
Current CPC
Class: |
B65G 17/086 20130101;
B65G 2201/02 20130101; B65G 17/08 20130101 |
Class at
Publication: |
198/618 |
International
Class: |
B65G 035/00 |
Claims
What is claimed is:
1. A radius conveyor belt, comprising: a plurality of belt modules
having a plurality of first link ends disposed in the direction of
belt travel and having a plurality of second link ends disposed in
the opposite direction, a cross-rib disposed between the first and
second link ends and having a web, and a corrugated portion
disposed adjacent to the web, the first and second link ends
disposed such that a space capable of receiving a link end is
formed between each adjacent link end, the space being open at one
end and terminating in an rounded region at the opposite end, the
plurality of first link ends being offset from the plurality of
second link ends such that the first link ends align with the space
between the second link ends such that adjacently positioned belt
modules are capable of intercalating so that the first link ends of
one belt module fit into the spaces defined between the second link
ends of an adjacent belt module, the plurality of first link ends
having a slot defined therein, the slot disposed transverse to the
direction of belt travel and extending in the direction of belt
travel, the plurality of second link ends having a transverse
opening defined therein; a pivot rod extending transverse to the
direction of belt travel through the openings in the second link
end of one of the plurality of belt modules and extending through
the slotted openings in the first link end of an adjacent belt
module such that the first and second link ends of the adjacent
belt modules are intercalated and the adjacent belt modules are
interlinked into adjacent hinged rows capable of following a curved
path; wherein the web on the cross-rib extends in the direction of
belt travel such that, when the belt is at its maximum extension in
the direction of belt travel, a space bounded by the web, an outer
end of the first link end and the sidewalls of second links ends
has a diameter less than 10 mm.
2. The radius conveyor belt of claim 1, wherein the first and
second link ends each have a leg portion with substantially
parallel sidewalls.
3. The radius conveyor belt of claim 2, wherein the first and
second link ends each have a head portion that is wider than the
leg portion, the head portion having a pair of substantially
parallel sidewalls and an endwall.
4. The radius conveyor belt of claim 3, wherein a junction of the
sidewalls and endwall of the head portion is rounded.
5. The radius conveyor belt of claim 3, wherein the endwall of the
head portion is rounded and connects a top surface of the link end
to a bottom surface of the link end.
6. The radius conveyor belt of claim 1, further comprising an
opening disposed through the belt module from the top surface to
the bottom surface.
7. The radius conveyor belt of claim 1, wherein the web and
corrugated portion form a multilevel surface defining the end of
the space between adjacent link ends.
8. A conveying system, comprising: an endless radius conveyor belt,
comprising a plurality of belt modules having a plurality of first
link ends disposed in the direction of belt travel and having a
plurality of second link ends disposed in the opposite direction,
the first and second link ends disposed such that a space capable
of receiving a link end is formed between each adjacent link end,
the space being open at one end and terminating in an rounded
region at the opposite end, the plurality of first link ends being
offset from the plurality of second link ends such that the first
link ends align with the space between the second link ends such
that adjacently positioned belt modules are capable of
intercalating so that the first link ends of one belt module fit
into the spaces defined between the second link ends of an adjacent
belt module, the plurality of first link ends having a slot defined
therein, the slot disposed transverse to the direction of belt
travel and extending in the direction of belt travel, the plurality
of second link ends having a transverse opening defined therein; an
intermediate portion disposed between the first and second link
ends and having a web and a corrugated portion, the web formed in
the center of the belt modules and disposed such that a first side
of the web terminates in a first surface of the belt module and a
second side of the web terminates adjacent to the corrugated
portion, wherein the web on the intermediate portion extends in the
direction of belt travel such that, when the belt is at its maximum
extension in the direction of belt travel, a space bounded by the
web, an outer end of the first link end and the sidewalls of second
links ends has a diameter less than 10 mm.; a pivot rod extending
transverse to the direction of belt travel through the openings in
the second link end of one of the plurality of belt modules and
extending through the slotted openings in the first link end of an
adjacent belt module such that the first and second link ends of
the adjacent belt modules are intercalated and the adjacent belt
modules are interlinked into adjacent hinged rows capable of
following a curved path; and, a drive sprocket having teeth
disposed around the perimeter thereof, the teeth capable of
engaging with the rounded endwall of the link ends to drive the
endless conveyor belt around a conveying path; and, wherein the web
and corrugated portion form a multilevel surface defining the end
of the space between adjacent link ends.
9. The conveying system of claim 8, wherein the first and second
link ends each have a leg portion with substantially parallel
sidewalls.
10. The conveying system of claim 9, wherein the first and second
link ends each have a head portion that is wider than the leg
portion, the head portion having a pair of substantially parallel
sidewalls and an endwall.
11. The conveying system of claim 10, wherein a junction of the
sidewalls and endwall of the head portion is rounded.
12. The conveying system of claim 10, wherein the endwall of the
head portion is rounded and connects a top surface of the link end
to a bottom surface of the link end.
13. The conveying system of claim 8, further comprising an opening
disposed through the belt module from the top surface to the bottom
surface.
14. The conveying system of claim 8, wherein the web and rounded
regions form a multilevel surface defining the end of the space
between adjacent link ends.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation-in-part
application claiming priority to U.S. patent application Ser. No.
09/579,090 filed May 25, 2000, and entitled "Radius Conveyor Belt,"
which is incorporated herein by reference.
FIELD OF INVENTION
[0002] This invention relates to conveyor belts and, more
particularly, to modular plastic conveyor belts formed of rows of
plastic belt modules pivotally interlinked by transverse pivot
rods.
BACKGROUND OF THE INVENTION
[0003] Because they do not corrode, are light weight, and are easy
to clean, unlike metal conveyor belts, plastic conveyor belts are
used widely, especially in conveying food products. Modular plastic
conveyor belts are made up of molded plastic modular links, or belt
modules, that can be arranged side by side in rows of selectable
width. A series of spaced apart link ends extending from each side
of the modules include aligned apertures to accommodate a pivot
rod. The link ends along one end of a row of modules are
interconnected with the link ends of an adjacent row. A pivot rod
journaled in the aligned apertures of the side-by-side and
end-to-end connected modules forms a hinge between adjacent rows.
Rows of belt modules are connected together to form an endless
conveyor belt capable of articulating about a drive sprocket.
[0004] In many industrial applications, conveyor belts are used to
carry products along paths including curved segments. Belts capable
of flexing sidewise to follow curved paths are referred to as
side-flexing, turn, or radius belts. As a radius belt negotiates a
turn, the belt must be able to fan out because the edge of the belt
at the outside of the turn follows a longer path than the edge at
the inside of the turn. In order to fan out, a modular plastic
radius belt typically has provisions that allow it to collapse at
the inside of a turn or to spread out at the outside of the
turn.
[0005] Apertures slotted in the direction of travel of the belt are
commonly provided in the link ends on at least one side of the
modules to facilitate the collapsing and spreading of the belt.
[0006] In applications where greater strength is required radius
belts with a larger pitch are required. These radius belts with a
large pitch (.gtoreq.1.5") have suffered from the disadvantage
that, due to the larger pitch and the need to be collapsible, the
grid openings were large enough to allow the finger of operators to
penetrate the grid. This situation may lead to injuries.
[0007] What is needed is a modular radius conveyor belt that has a
large pitch yet reduces the gap between the links to less than 10
mm to prevent fingers from penetrating the grid.
SUMMARY OF THE INVENTION
[0008] The present invention meets the above-described need by
providing a radius belt having belt modules with a cross-rib
designed so as to allow the link ends to undercut the cross-rib
when collapsing. The module has a cross-rib with an extended
portion in the longitudinal direction. The modules include first
and second module surfaces, i.e., a top, product-conveying surface
and a bottom, sprocket-driven surface. A cross-rib extends across
the width of each module transverse to the direction of belt
travel. The cross-rib is formed in part by a web and in part by a
thin, corrugated strip having a pair of essentially parallel walls.
The corrugated strip forms a series of regularly spaced alternating
ridges and valleys along each wall. Link ends extend outward from
the ridges on each wall of the corrugated strip. Each link end has
a leg portion attached at a ridge of the strip and a thick distal
portion at the end of the link end distant from the corrugated
strip. Transverse holes in the link ends extending from respective
walls of a module are aligned to accommodate a pivot rod. When the
link ends of consecutive rows of side-by-side modules are
intercalated, the pivot rod serves as a hinge pin in a hinged joint
between consecutive interlinked rows. To permit the belt to follow
a curved path, the pivot rod openings in at least one of the link
ends extending from one of the walls of the corrugated strip are
slotted longitudinally in the direction of belt travel.
[0009] The belt is driven by engagement of the sprocket tooth with
the curved outside surface of the link ends. The link end engaged
by the sprocket tooth is subjected to a compressive force rather
than an undesirable tensile force. Thus, the link ends provide pull
strength, resistance to belt and sprocket wear, and sprocket
drivability. As an alternative, a central portion of a link end
disposed in the middle belt modules may also engage with a tooth on
the drive sprocket. Because the mid modules do not have to collapse
fully, they may be formed with a thicker and fully straight
cross-rib.
[0010] Each wall of the corrugated strip forms a series of arched
recesses with the leg portions of the link ends. The recesses are
large enough to provide room for a thick link end of an interlinked
module of an adjacent row to collapse into the recess or to rotate
as belt rows fan out going around a turn. Because the recesses
along one wall overlap in a transverse direction with the recesses
along the other wall, additional space for collapsing is
provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The invention is illustrated in the drawings in which like
reference characters designate the same or similar parts throughout
the figures of which:
[0012] FIG. 1 is a top plan view of a radius conveyor belt module
of the present invention;
[0013] FIG. 2 is a bottom plan view of the belt module of the
present invention;
[0014] FIG. 3 is an end elevation view of the belt module of the
present invention;
[0015] FIG. 4 is an end elevation view of the belt module of the
present invention;
[0016] FIG. 5 is a top perspective view of the belt module of the
present invention;
[0017] FIG. 6 is a bottom perspective view of the belt module of
the present invention;
[0018] FIG. 7 is a top plan view of a radius belt of the present
invention;
[0019] FIG. 8 is a partial detailed view of a section of the belt
of FIG. 7;
[0020] FIG. 9 is a side elevational view of a belt of the present
invention engaged with a sprocket and illustrating the gaps between
adjacent modules.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Referring now to the drawings, FIGS. 1 to 9 show a first
embodiment of a modular belt 20 of the present invention. The
portion of the modular belt 20 shown is formed from molded plastic
modules 23, 26, 27 and 29 (FIG. 7). For reference, the direction of
belt travel is indicated by arrow 32, however, the belt of the
present invention may be conveyed in either direction. A pivot rod
35 (FIG. 7) connects adjacent belt modules by passing through
openings in the modules disposed transverse to the direction of
belt travel.
[0022] As shown in FIG. 1, an exemplary one of the belt module 26
has a cross-rib 38 supporting a plurality of first link ends 41 and
a plurality of second link ends 44. The first link ends 41 are
disposed in the direction of belt travel indicated by arrow 32 and
the plurality of second link ends 44 extend opposite the first link
ends 41. As will be described in detail hereinafter, the cross-rib
38 is comprised of an upper, transverse stiffening web 47 forming
into a lower corrugated portion 50 (shown in broken lines in FIG.
1). The corrugated portion 50 forms a series of ridges 53 and
valleys 56 in a sinusoidal manner. Along with the transverse web 47
of the cross-rib 38, the ridges 53 extending toward the right of
FIG. 2 support the first link ends 41 while the ridges 53 extending
toward the left in the drawing support the second link ends 44.
[0023] The first link ends 41 include a leg portion 59 connected
through an angled portion 62 to a distal head portion 65. In a
similar manner, the second link ends 44 include a leg portion 68
connected through an angled portion 71 to a distal head portion
74.
[0024] With respect to the orientation shown in FIG. 3, the
cross-rib 38, which is formed of the stiffening web 47 and the
corrugated portion 50 (FIG. 2), is comprised of an upper surface 77
extending to and meeting with opposed left and right walls 80 and
83 which, in turn, meet with a lower surface 86 of the module. The
left wall 80 is comprised of an upper wall 89, which is part of the
stiffening web 47, and extends downwardly to a curved wall 92 which
forms into a lower vertical wall 95. The curved wall 92 and the
lower vertical wall 95 are part of the corrugated portion 50 of the
cross-rib 38. The lower vertical wall 95 extends to the lower
surface 86 of the module which, in turn, extends to and meets with
the right vertical wall 83.
[0025] As shown in FIG. 2, the head portion 65 is preferably larger
than the leg portion 59. Accordingly, the head portion 65 is
connected to the leg portion 59 by the angled portion 62. The head
portion 65 is preferably formed with two substantially parallel
sides 98 and 101 connected by an outer end 104. The corners between
the sides 98, 101 and ends 104 are preferably radiused to be smooth
and to protect the conveyed product from damage.
[0026] An opening 107 is defined between spaced apart sides 110,
113 of adjacent link ends. At a distal end 116, the ends of
adjacent links form the mouth 119 of the opening 107. At the
opposite end 122, the opening 107 terminates in the multi-level
surface defined by the web 47 and corrugated portion 50 as
described above. The top level of the surface (best shown in FIG.
1) is defined by wall 89 (FIG. 3) of the web 47. The corners where
the side walls of the link ends 41 meet the straight wall 89 of web
47, are also radiused to be smooth and to protect the conveyed
product from damage.
[0027] In FIG. 2, the bottom level of the surface of cross-rib 38
is defined by the relatively thin corrugated portion 50 having a
pair of essentially parallel walls 125, 128. The corrugated portion
50 forms the series of regularly spaced alternating ridges 53 and
valleys 56 along the cross-rib 38 as described herein.
[0028] Returning to FIG. 1, the straight wall 89 is shown bordering
the opening 107. The curved surface defined by corrugated portion
50 is shown in broken lines. The curved surface receives link ends
from an adjacent belt module such that the belt 20 is capable of
collapsing for movement around a curved path as described in detail
herein.
[0029] The plurality of second link ends 44 extend from the belt
module 26 in the opposite direction from the first link ends 41.
The second link ends 44 have the same overall shape as the first
link ends 41 and are designed to fit into the openings between the
first link ends 41 such that adjacent belt modules can be
intercalated and pivotally connected by the pivot rods 35.
[0030] As shown in FIG. 3, the belt module 26 includes a slot 134
that is disposed through the link ends 41 transverse to the
direction of belt travel. The slot 134 extends in the direction of
belt travel such that it is generally oblong. The slot 134 receives
the pivot rod 35. The pivot rod 35 passes through the slots 134 in
the first link ends 41 and through the openings 137 in the second
link ends 44 (as shown in FIG. 7). The openings 137 correspond to
the shape of the shaft 138 (FIG. 7) of the pivot rod 35 such that
the pivot rod 35 is received through the opening 137 but in
contrast to slot 134, the pivot rod 35 preferably cannot move in
the direction of belt travel inside opening 137. Due to the oblong
shape of slot 134, the pivot rod 35 can pivot inside the slot 134
such that the belt 20 is capable of collapsing on one side while
the other side fans out due to the pivoting of rod 35 and the
nesting of the link ends 41, 44 and cooperating spaces in the
adjacent belt modules.
[0031] In FIG. 4, the last link end 45 of the belt module 26
includes a second opening 140 disposed around opening 137 to
provide for countersinking a head (not shown) at the end of the
pivot rod shaft 138.
[0032] The transverse slot 134 in link ends 41 and the transverse
opening 137 in link ends 44 receive pivot rods 35 to connect
adjacent belt modules 23 and 29 as shown in FIG. 7. As shown in
FIG. 5, the web 47 is coterminous with the top surface 77 of the
belt module 26 and terminates at the top of the corrugated portion
50 that defines the space between adjacent link ends (best shown in
FIG. 6).
[0033] The outer ends 104 of the link ends 41 and 44 are radiused
in a smooth rounded surface 146. The rounded surface 146 preferably
comprises a rounded surface having a constant radius and provides a
driving surface for engagement with the drive sprocket 149 as
described herein.
[0034] Also, the curvature of the outer ends 104 of the link ends
enables the links to clear the web 47 when the adjacent modules
collapse along the edge. The clearance enables the link ends to
extend under the web 47 into the space defined by the corrugated
portion 50 (best shown in FIGS. 5-6). In this manner, the web 47
partially hoods the link ends when the belt 20 collapses.
Accordingly, the belt module 26 provides a web 47 for structural
stability while maintaining a corrugated portion 50 to allow for
recesses that provide maximum space for collapsing the belt modules
around a curved path.
[0035] In FIG. 7, the belt 20 is shown at its maximum lengthwise
extension. For example, the maximum lengthwise extension creates
spaces 200 bordered by the cross-rib 38, the link ends 44 of module
23 and the link ends 41 of the adjacent module. In order to prevent
small fingers from penetrating the belt grid and engaging with a
belt support 205 (FIG. 9), the top surface 77 of the cross-rib is
extended such that the opening 200 described above is less than 10
mm. At the top conveying surface, the opening 200 is bordered on
one side by upper wall 89. The space 200 is also bordered by sides
110, 113, of adjacent link ends 44. The end of space 200 opposite
from upper wall 89 is defined by the outer end 104 of link end 41
on the adjacent belt module 26. Also, a portion of the sides 98 and
101 of link end 41 border space 200.
[0036] For belts having a pitch greater than or equal to 1.5
inches, the openings created in the belt grid may allow for fingers
to penetrate the grid.
[0037] In the present invention, for belts having pitches greater
than or equal to 1.5 inches, extending the upper wall 89 outward
from the cross-rib 38 reduces the size of space 200. The upper wall
89 is sized so that when the belt 20 is fully extended lengthwise
the space 200 has critical opening widths or diameter less than 10
mm. Critical opening width or diameter is defined as the distance
of the opening across its smallest dimension.
[0038] The extended upper wall 89 is sized to reduce the size of
the opening yet allows the belt 20 to collapse without obstruction.
The curvature of the link end from the top surface provides for
nesting of the link end beneath the upper wall 89.
[0039] In FIG. 9, the belt modules 20 are shown driven by the teeth
148 on the drive sprocket 149. The drive sprocket 149 is driven by
a rotating shaft (not shown) as known to those of ordinary skill in
the art. A cylindrical member 210, which is representative of a
small finger, has a diameter of 10 mm. As shown, the space 200 is
not large enough to accommodate the member 210.
[0040] Accordingly, a radius belt 20 suitable for larger pitch
(.gtoreq.1.5") radius belt applications has been disclosed. The
belt 20 has an extended cross-rib 38 that reduces the space 200 to
less than lOmm width so as to prevent fingers of a user from
penetrating the belt grid.
[0041] While the invention has been described in connection with
certain preferred embodiments, it is not intended to limit the
scope of the invention to the particular forms set forth, but, on
the contrary, it is intended to cover such alternatives,
modifications, and equivalents as may be included within the spirit
and scope of the invention as defined by the appended claims.
* * * * *