U.S. patent application number 10/289630 was filed with the patent office on 2003-04-03 for contact assembly for accumulation conveyors.
This patent application is currently assigned to Rapistan Systems Advertising Corp.. Invention is credited to Cotter, David H., Ehlert, Ronald C., Kooistra, Kenneth J., LeMay, Curtis E., Pelak, Thomas J..
Application Number | 20030062249 10/289630 |
Document ID | / |
Family ID | 26902514 |
Filed Date | 2003-04-03 |
United States Patent
Application |
20030062249 |
Kind Code |
A1 |
Cotter, David H. ; et
al. |
April 3, 2003 |
Contact assembly for accumulation conveyors
Abstract
A contact assembly for an accumulation conveyor includes a
support member having a cavity dimensioned to receive a force
producing device. A contact member is positioned between the force
producing device and the conveying rollers and reciprocates with
respect to the conveying rollers. The contact member includes a
wheel assembly which, when vertically reciprocated by the
force-producing device, places the drive belt into driving contact
with the conveying rollers. The wheel assembly is configured to
move in a substantially transverse direction to the direction of
movement of the drive belt to maintain alignment between the drive
belt and the contact assembly.
Inventors: |
Cotter, David H.;
(Coopersville, MI) ; Ehlert, Ronald C.; (Wyoming,
MI) ; Pelak, Thomas J.; (Grand Rapids, MI) ;
Kooistra, Kenneth J.; (Byron Center, MI) ; LeMay,
Curtis E.; (Shelbyville, MI) |
Correspondence
Address: |
VAN DYKE, GARDNER, LINN AND BURKHART, LLP
2851 CHARLEVOIX DRIVE, S.E.
P.O. BOX 888695
GRAND RAPIDS
MI
49588-8695
US
|
Assignee: |
Rapistan Systems Advertising
Corp.
Grand Rapids
MI
|
Family ID: |
26902514 |
Appl. No.: |
10/289630 |
Filed: |
November 7, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10289630 |
Nov 7, 2002 |
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09725583 |
Nov 29, 2000 |
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6478142 |
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09725583 |
Nov 29, 2000 |
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09207712 |
Dec 9, 1998 |
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Current U.S.
Class: |
198/835 |
Current CPC
Class: |
B65G 47/261
20130101 |
Class at
Publication: |
198/835 |
International
Class: |
B65G 023/04 |
Claims
The embodiments of the present invention in which an exclusive
property or privilege is claimed are defined as follows:
1. A contact assembly for an accumulation conveyor having a
plurality of conveying rollers and an endless drive member having
an upper portion traveling in a plane, said contact assembly
selectively reciprocally movable into engagement with the endless
drive member to bring the upper portion of the endless drive member
into selective engagement with the conveying rollers, at least a
portion of said contact assembly configured to move in said plane
to align said contact assembly with said endless drive member.
2. The contact assembly of claim 1, wherein movement of said
portion of said contact assembly into alignment with the endless
drive member displaces another portion of said contact assembly in
a manner which moves the endless drive member into alignment with
said contact assembly.
3. The contact assembly of claim 2, wherein said portion is
upstream of said another portion with respect to movement of the
endless drive member.
4. The contact assembly of claim 3, wherein said contact assembly
pivots about an axis that is closer to said portion than to said
another portion.
5. The contact assembly of claim 1, wherein a surface of the
endless drive member having a substantially vertical component
engages a surface of said contact assembly to move said contact
assembly in said plane.
6. The contact assembly of claim 5, wherein said surface of said
contact assembly is at an upstream portion with respect to the
movement of the endless drive member.
7. The contact assembly of claim 5, wherein said contact assembly
pivots about a substantially vertical axis.
8. The contact assembly of claim 7, wherein said substantially
vertical axis is closer to said upstream portion than to a
downstream portion of said contact assembly.
9. The contact assembly of claim 1, wherein said contact assembly
includes at least one contact roller having a crowned surface,
wherein engagement between the endless drive member and said
crowned surface moves said contact assembly in said plane.
10. The contact assembly of claim 9, wherein said at least one
contact roller has at least one end formed with a flange, wherein
engagement between the endless drive member and said flange moves
said contact assembly in said plane.
11. The contact assembly of claim 1, wherein said contact assembly
includes at least one contact roller having at least one end formed
with a flange, wherein engagement between the endless drive member
and said flange moves said contact assembly in said plane.
12. The contact assembly of claim 11, wherein said at least one
contact roller is a first contact roller and a second contact
roller, wherein said first contact roller has at least one end
formed with a flange and is positioned upstream of said second
contact roller with respect to the movement of the endless drive
member.
13. The contact assembly of claim 5, wherein the endless drive
member has an inner surface formed with a protrusion, and wherein
said contact assembly includes at least one pair of spaced apart
contact rollers defining a space therebetween, wherein the
protrusion is positioned within said space, and wherein said
surface of said contact assembly is an inner surface of a contact
roller of said at least one pair of contact rollers.
14. The contact assembly of claim 13, wherein said at least one
pair of contact rollers is a first pair of contact rollers and a
second pair of contact rollers, wherein said first pair of contact
rollers is positioned upstream of said second pair of contact
rollers with respect to the movement of the endless drive
member.
15. The contact assembly of claim 1, further comprising a platform
having at least one drive member engagement section, said at least
one drive member engagement section reciprocally engaging the
endless drive member.
16. The contact assembly of claim 15, further comprising a support
member, said support member supporting said platform, said support
member formed with an orientation member.
17. The contact assembly of claim 15, wherein said at least one
drive member engagement section is configured to move said platform
in said plane when said at least one drive member engagement
section engages the endless drive member.
18. The contact assembly of claim 15, wherein said at least one
drive member engagement section is a first drive member engagement
section and a second drive member engagement section.
19. The contact assembly of claim 18, wherein said first drive
member engagement section is a first contact roller and said second
drive member engagement section is a second contact roller, said
first contact roller positioned first in the direction of travel of
the endless drive member, one of said contact rollers having a pair
of ends, at least one end of said pair of ends formed with an
out-turned flange, wherein contact between the endless drive member
and said out-turned flange moves said platform in said plane.
20. The contact assembly of claim 19, wherein said out-turned
flange is formed on an end of said first contact roller.
21. The contact assembly of claim 19, wherein said out-turned
flange is formed on each end of said first contact roller.
22. The contact assembly of claim 18, wherein said first drive
member engagement section is a first pair of contact rollers and
said second drive member engagement section is a second pair of
contact rollers.
23. The contact assembly of claim 22, wherein the endless drive
member has an undersurface formed with a protrusion projecting
therefrom and is positioned between said first pair of contact
rollers and said second pair of contact rollers when said first
pair and said second pair of contact rollers engage the endless
drive member.
24. The contact assembly of claim 23, wherein the protrusion of the
endless drive member has a width and each contact roller of said
first pair of contact rollers and said second pair of contact
rollers has an inner surface, at least one pair of said first pair
of contact rollers and said second pair of contact rollers being
spaced a preselected distance apart, wherein said preselected
distance is slightly greater than the width of the protrusion so
that contact between said inner surface of a contact roller and the
protrusion moves said platform in said plane.
25. The contact assembly of claim 24, wherein said first pair of
contact rollers are spaced said preselected distance apart and
positioned first in the direction of movement of the endless drive
member.
26. The contact assembly of claim 25, wherein said first pair of
contact rollers are spaced a first distance apart and said second
pair of contact rollers are spaced a second distance apart, wherein
said second distance is greater than said first distance.
27. An accumulation conveyor comprising: a plurality of conveying
rollers, and an endless drive member juxtaposed with said conveying
rollers, said endless drive member having an upper portion
traveling in a plane; a support member having at least one
generally vertical guide member; a force-producing device carried
by said support member; and a contact member supported by said
support member, wherein actuation of said force-producing device
moves said contact member into engagement with said endless drive
member and said endless drive member into engagement with said
conveying rollers, wherein engagement between said contact member
and said endless drive member pivotally moves said contact member
about said at least one guide member in said plane to align said
contact member with said endless drive member.
28. The accumulation conveyor of claim 27, wherein said at least
one generally vertical guide member is a first generally vertical
guide member and a second generally vertical guide member, wherein
said contact member pivotally moves about said first generally
vertical guide member and said second generally vertical guide
member limits movement of said contact member.
29. The accumulation conveyor of claim 27, wherein said contact
member has at least one drive member engagement section, wherein
actuation of said force-producing device moves said at least one
drive member engagement section into engagement with said endless
drive member and said endless drive member into engagement with
said conveying rollers, wherein engagement between said at least
one drive member engagement section and said endless drive member
pivotally moves said contact member about said at least one guide
member to align said contact member with said endless drive
member.
30. The accumulation conveyor of claim 29, wherein said at least
one drive member engagement section is a first drive member
engagement section and a second drive member engagement
section.
31. The accumulation conveyor of claim 30, wherein said first drive
member engagement section is at least a first contact roller and
said second drive member engagement section is at least a second
contact roller.
32. The accumulation conveyor of claim 31, wherein said first
contact roller has a pair of ends, at least one end of said pair of
ends formed with an out-turned flange, wherein contact between said
out-turned flange and said endless drive member pivots said contact
member about said at least one guide member to thereby align said
contact member with said endless drive member.
33. The accumulation conveyor of claim 32, wherein at least one of
said first contact roller and said second contact roller is a
crowned contact roller.
34. The accumulation conveyor of claim 32, wherein each end of said
first contact roller is formed with an out-turned flange.
35. The accumulation conveyor of claim 31, wherein said first
contact roller is positioned first in the direction of travel of
said endless drive member.
36. The accumulation conveyor of claim 30, wherein said contact
member is formed with at least one post having a channel
dimensioned to receive said at least one generally vertical guide
member.
37. The accumulation conveyor of claim 36, wherein said generally
vertical guide member is a first guide member and a second guide
member, said contact assembly pivotally moving about said first
guide member, wherein said first guide member is positioned closer
to said first drive member engagement section than to said second
drive member engagement section.
38. The accumulation conveyor of claim 37, wherein said at least
one post is a first post and a second post, said first post having
a first channel dimensioned to receive said first guide member,
said second post having a second channel dimensioned to receive
said second guide member.
39. The accumulation conveyor of claim 38, wherein said first
channel has a first diameter, wherein said second channel has a
second diameter, said second diameter being greater than said first
diameter.
40. The accumulation conveyor of claim 27, wherein said support
member is formed with a rib extending therefrom in a substantially
vertical direction.
41. The accumulation conveyor of claim 31, wherein said endless
drive member has a substantially flat cross section.
42. The accumulation conveyor of claim 30, wherein said first drive
member engagement section is a first pair of contact rollers and
said second drive member engagement section is a second pair of
contact rollers.
43. The accumulation conveyor of claim 42, wherein said endless
drive member has an undersurface formed with a protrusion
projecting therefrom, said protrusion positioned between said first
pair of contact rollers and said second pair of contact rollers
when said first pair of contact rollers and said second pair of
contact rollers engage said endless drive member.
44. The accumulation conveyor of claim 43, wherein said protrusion
has a width and each contact roller of said first pair of contact
rollers and said second pair of contact rollers has an inner
surface, at least one pair of said first pair of contact rollers
and said second pair of contact rollers being spaced a preselected
distance apart, wherein said preselected distance is slightly
greater than said width of said protrusion so that contact between
said inner surface of a contact roller and said protrusion pivots
said contact member.
45. The accumulation conveyor of claim 44, wherein said first pair
of contact rollers are spaced said preselected distance apart and
positioned first in the direction of travel of said endless drive
member.
46. The accumulation conveyor of claim 45, wherein said first pair
of contact rollers are spaced a first distance apart and said
second pair of contact rollers are spaced a second distance apart,
wherein said second distance is greater than said first
distance.
47. The accumulation conveyor of claim 44, wherein said at least
one generally vertical guide member is a first guide member and a
second guide member, and said contact member includes a first post
and a second post, said first post having a first channel
dimensioned to receive said first guide member, said first post
positioned proximate to said first pair of contact rollers, said
second post having a second channel dimensioned to receive said
second guide member, said second post positioned proximate to said
second pair of contact rollers.
48. The accumulation conveyor of claim 47, wherein said first
channel has a first diameter, wherein said second channel has a
second diameter, said second diameter being greater than said first
diameter.
49. A contact assembly for an accumulation conveyor having a
plurality of conveying rollers, and an endless drive member having
an upper portion juxtaposed with the conveying rollers, wherein the
upper portion of the endless drive member travels in a plane, said
contact assembly comprising: a support member; a force-producing
device carried by said support member; and a wheel assembly
positioned between said force-producing device and the conveying
rollers, wherein actuation of said force-producing device moves
said wheel assembly into engagement with the upper portion of the
endless drive member and the upper portion of the endless drive
member into engagement with the conveying rollers, said wheel
assembly including at least one upstream roller and at least one
downstream roller, said wheel assembly pivoting about a
substantially vertical axis, wherein contact between said at least
one upstream roller and the endless drive member pivots said wheel
assembly about said substantially vertical axis to maintain
alignment between said wheel assembly and the endless drive member,
said vertical axis being between said at least one upstream roller
and said at least one downstream roller and closer to said at least
one upstream roller.
50. The contact assembly of claim 49, wherein said at least one
upstream roller has at least one end formed with an out-turned
flange, wherein contact between said at least one out-turned flange
and the endless drive member pivots said wheel assembly about said
substantially vertical axis.
51. The contact assembly of claim 49, wherein said at least one
upstream roller is a first pair of contact rollers and said at
least one downstream roller is a second pair of contact
rollers.
52. The contact assembly of claim 51, wherein the endless drive
member has an undersurface formed with a protrusion projecting
therefrom and positioned between said first pair of contact rollers
and said second pair of contact rollers when said first pair of
contact rollers and said second pair of contact rollers engage the
endless drive member.
53. The contact assembly of claim 52, wherein the protrusion has a
width and each contact roller of said first pair of contact rollers
and said second pair of contact rollers has an inner surface, at
least one pair of said first pair of contact rollers and said
second pair of contact rollers being spaced a preselected distance
apart, wherein said preselected distance is slightly greater than
the width of the protrusion so that contact between said inner
surface of a contact roller and said protrusion pivots said wheel
assembly about said substantially vertical axis.
54. The contact assembly of claim 53, wherein said first pair of
contact rollers are spaced said preselected distance apart and
positioned first in the direction of travel of the endless drive
member.
55. The contact assembly of claim 54, wherein said first pair of
contact rollers are spaced a first distance apart and said second
pair of contact rollers are spaced a second distance apart, wherein
said second distance is greater than said first distance.
56. The contact assembly of claim 49, wherein said support member
has a horizontal surface and at least one guide member extending
from said horizontal surface, said wheel assembly pivoting about
said at least one guide member.
57. The contact assembly of claim 56, wherein said wheel assembly
is formed with at least one post, said at least one post having a
channel dimensioned to receive said at least one guide member.
58. The contact assembly of claim 57, wherein said at least one
guide member is a first guide member and a second guide member, and
wherein said at least one post is a first post and a second post,
said first post having a first channel dimensioned to receive said
first guide member, said first post positioned proximate to said
first pair of contact rollers, said second post having a second
channel dimensioned to receive said second guide member, said
second post positioned proximate to said second pair of contact
rollers.
59. The contact assembly of claim 58, wherein said first channel
has a first diameter, wherein said second channel has a second
diameter, said second diameter being greater than said first
diameter.
60. The contact assembly of claim 49, wherein said support member
is formed with an orientation member.
61. An accumulation conveyor comprising: a plurality of conveying
rollers and an endless drive member juxtaposed with said plurality
of conveying rollers, said endless drive member formed with an
undersurface having a protrusion extending therefrom, said
protrusion having a width, said endless drive member traveling in a
direction; a support member, said support member having a
horizontal surface and at least one guide member extending from
said horizontal surface; a force-producing device carried by said
support member; and a wheel assembly positioned between said
force-producing device and said endless drive member and supported
by said support member, said wheel assembly rotatably positioned on
said at least one guide member to rotate about a generally vertical
axis, said wheel assembly having a first pair of contact rollers
and a second pair of contact rollers, said first pair of contact
rollers positioned first in said direction of travel of said
endless drive member, each contact roller of said first pair of
contact rollers having an inner surface, wherein actuation of said
force-producing device moves said first pair of contact rollers and
said second pair of contact rollers into engagement with said
endless drive member and said endless drive member into engagement
with said conveying rollers, wherein said protrusion is positioned
between said first pair of contact rollers and said second pair of
contact rollers when said first pair of contact rollers and said
second pair of contact rollers engage said endless drive member,
and wherein said first pair of contact rollers are positioned a
preselected distance apart, said preselected distance being
slightly greater than said width of said protrusion such that
contact between an inner-surface of a contact roller of said first
pair contact rollers and said protrusion pivots said wheel assembly
to thereby maintain alignment between said wheel assembly and said
endless drive member.
62. The accumulation conveyor of claim 61, wherein said wheel
assembly is formed with at least one post, said at least one post
having a channel dimensioned to receive said at least one guide
member.
63. The accumulation conveyor of claim 62, wherein said at least
one guide member is a first guide member and a second guide member
and wherein said at least one post is a first post and a second
post, said first post having a first channel dimensioned to receive
said first guide member, said first post positioned proximate to
said first pair of contact rollers, said second post having a
second channel dimensioned to receive said second guide member,
said second post positioned proximate to said second pair of
contact rollers, said wheel assembly pivoting about said first
guide member when said protrusion contacts an inner surface of a
contact roller of said first pair of contact rollers.
64. The accumulation conveyor of claim 63, wherein said first
channel has a first diameter, wherein said second channel has a
second diameter, said second diameter being greater than said first
diameter.
65. An accumulation conveyor comprising: a plurality of conveying
rollers and an endless drive member juxtaposed with said conveying
rollers, an upper portion of said endless drive member traveling in
a plane; at least one sensor for sensing that said endless drive
member is misaligned in said plane; and at least one contact
assembly operably interconnected with said at least one sensor,
said at least one contact assembly selectively reciprocally movable
into engagement with the endless drive member to bring the endless
drive member into selective engagement with the conveying rollers,
said at least one contact assembly including a portion that is
moveable in said plane in response to said at least one sensor
sensing that said endless member is misaligned in said plane.
66. The accumulation conveyor of claim 65, wherein said at least
one contact assembly is configured to move into alignment with said
endless drive member when said at least one sensor senses that said
endless drive member is misaligned in said plane.
67. The accumulation conveyor of claim 66, wherein movement of a
portion of said contact assembly into alignment with the endless
drive member displaces another portion of said contact assembly in
a manner which moves the endless drive member into alignment with
said contact assembly.
68. The accumulation conveyor of claim 67, wherein said portion is
upstream of said another portion with respect to the movement of
said endless drive member.
69. The accumulation conveyor of claim 65, wherein said contact
assembly is configured to pivot about a substantially vertical
axis.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This is a continuation-in-part application of co-pending
U.S. patent application Ser. No. 09/207,712, filed Dec. 9, 1998,
and now abandoned, the entire disclosure of which is hereby
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The invention relates generally to accumulation conveyors
and, more particularly, to pneumatically actuated accumulation
conveyors.
[0003] Accumulation conveyors normally include conveying rollers
that support product being conveyed and when rotated, transport the
same in a particular direction. Positioned below the conveying
rollers is an endless drive member, such as a composite belt, a
padded chain, a linked belt, and the like, which is driven by a
drive motor. The accumulation conveyor system is normally divided
into a plurality of zones. Each zone of the conveyor is equipped
with a product sensor for detecting the presence or absence of
product at a particular position along the conveyor. Each of these
sensors is operationally connected to a contact assembly positioned
below the top run of the endless drive member. Each contact
assembly includes a pneumatically, mechanically or electrically
driven vertically reciprocal contact member which may be operated
individually or be operationally interconnected with contact
assemblies positioned in other zones of the conveyor.
[0004] In accordance with a particular control scheme dictating the
selective movement of product along the conveyor, one or more of
the contact assemblies are actuated to move the contact member into
frictional contact with the endless drive member. When a particular
contact member is in such frictional engagement with the endless
drive member, the conveying rollers adjacent the control assembly
are engaged by the top surface of the top run of the endless drive
member and begin to rotate. This rotation in turn results in the
transportation of product supported by the selected conveying
rollers.
[0005] When it is desired to accumulate product within a particular
zone of the conveyor the contact assembly within that zone
vertically retracts, and hence moves out of driving engagement with
the endless drive member. This in turn results in the disengagement
of the top surface of the endless drive member from contact with
the conveying rollers and thus, such conveying rollers cease
rotation.
[0006] The endless drive member of the accumulation conveyor has a
tendency to become misaligned with the contact assembly. Over the
length of the conveyor, this misalignment may become pronounced and
may cause the endless drive member to deviate from one or more
contact members. This misalignment may be encountered whether using
generally flat drive belts or V-shaped belts, i.e., belts having a
protrusion formed on the lower surface. This deviation may even
result in contact between the endless drive member and a side
support rail, causing damage to both the endless drive member and
the conveyor, as well as the inefficient conveyance of product.
[0007] Therefore, there exists a need for a contact assembly for an
accumulation conveyor which overcomes the difficulties of the prior
art while being exceptionally functional and economical to
manufacture.
SUMMARY OF THE INVENTION
[0008] The invention is useful with an accumulation conveyor having
an endless drive member, a plurality of conveying rollers and a
plurality of contact assemblies configured to selectively
reciprocally move into engagement with the endless drive member to
move the endless drive member into engagement with the conveying
rollers. According to an aspect of the invention, the contact
assembly includes at least a portion configured to move in the
plane of the endless drive member when in engagement with the
endless drive member to thereby align the contact assembly and the
endless drive member. Providing a contact assembly, a portion of
which moves in the plane of the endless drive member, maintains the
alignment between the contact assembly and the endless drive
member, assuring that the endless drive member remains centered
upon the contact assembly, and hence, maximizes efficient
operation.
[0009] According to another aspect of the invention, an
accumulation conveyor includes an endless drive member that is
juxtaposed with a plurality of conveying rollers and travels in a
particular plane. At least one sensor senses that the endless drive
member is misaligned. At least one contact assembly is operably
interconnected with the sensor and is selectively movable to bring
the endless drive member into alignment with the associated contact
assembly. The contact assembly includes a portion that is movable
in the plane of the endless drive member. In this manner, the at
least one contact assembly is configured to realign the endless
drive member in response to the sensor sensing that the endless
drive member is misaligned. The employment of a sensor operably
connected to a contact assembly capable of realigning the endless
drive member provides a reliable, effective control system for
maintaining the alignment of the endless drive member.
[0010] According to yet another aspect of the invention, an
accumulation conveyor includes a support member formed with at
least one generally vertical guide member extending therefrom and
carrying a force producing device. A contact member is supported by
the support member and is moved into engagement with the endless
drive member upon actuation of the force producing device.
Engagement between the contact member and the endless drive member
pivots the contact member about the at least one guide member to
align the contact member with the endless drive member. This
pivotal compliance maintains alignment between the contact member
and the endless drive member, and hence prevents the endless drive
member from moving off the contact member and potentially causing
damage to the conveyor.
[0011] According to still yet another aspect of the invention, a
contact assembly for an accumulation conveyor includes a support
member, a force producing device carried by the support member, and
a wheel assembly positioned between the force producing device and
the conveying rollers. The wheel assembly includes at least one
upstream roller and at least one downstream roller. Contact between
the wheel assembly and the endless drive member pivots the wheel
assembly about a substantially vertical axis between the upstream
and downstream roller and closer to the upstream roller to thereby
maintain alignment between the wheel assembly and the endless drive
member.
[0012] According to still yet another aspect of the invention, an
accumulation conveyor includes a force producing device carried by
a support member, and a wheel assembly positioned between the force
producing device and the support member. The wheel assembly is
rotatably positioned on the at least one guide member and rotates
about a generally vertical axis. The wheel assembly includes a
first pair of contact rollers and a second pair of contact rollers.
The first pair of contact rollers are positioned first in the
direction of travel of the endless drive member, and are positioned
a distance apart, whereby the distance is slightly larger than the
width of the protrusion formed in the endless drive member. Contact
between an inner surface of a contact roller of the first pair of
contact rollers and the protrusion of the endless drive member
pivots the platform to thereby maintain alignment between the
platform and the endless drive member. Providing a pair of contact
rollers attached to a pivoting platform, which are spaced so that
engagement between the protrusion and the contact rollers pivots
the platform to maintain alignment provides an effective and
reliable structure for maintaining alignment between the platform
and the endless drive member.
[0013] These and other objects, advantages, purposes, and features
of the invention will become apparent upon review of the following
specification in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a perspective view of a segment of an accumulation
conveyor according to the invention;
[0015] FIG. 2 is side elevation of the accumulation conveyor
segment of FIG. 1;
[0016] FIG. 3 is a perspective view of a contact assembly according
to the invention;
[0017] FIG. 4 is a perspective view of the contact member of FIG.
3;
[0018] FIG. 5 is a bottom view of the contact member depicted in
FIG. 4, shown without the contact rollers attached thereto;
[0019] FIG. 6 is a cross sectional view of the contact member
depicted in FIG. 5, taken along line VI-VI of FIG. 5;
[0020] FIG. 7 is a perspective view of a support member of FIG.
3;
[0021] FIG. 8 is a top plan view of the support member illustrated
in FIG. 7;
[0022] FIG. 9 is a detailed view of a guide member according to the
invention;
[0023] FIG. 10 is a perspective view of a segment of an
accumulation conveyor according to an alternative preferred
embodiment of the invention, with a portion of the endless drive
member cut away;
[0024] FIG. 11 is a perspective view of a contact member depicted
in FIG. 10;
[0025] FIG. 12 is a perspective view of a support member depicted
in FIG. 10;
[0026] FIG. 13 is a partially fragmented, rear view of the contact
assembly depicted in FIG. 10, with the endless drive member shown
in cross section;
[0027] FIG. 14 is a partially fragmented, front view of the contact
assembly depicted in FIG. 13, with the endless drive member shown
in cross section; and
[0028] FIG. 15 is a plan view of an accumulation conveyor according
to an alternative preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] The present invention finds particular application as a
contact assembly for use in conjunction with the conveyor set forth
in the commonly assigned U.S. Pat. No. 5,540,323 issued to
Schiesser et al. for a MODULAR PNEUMATIC ACCUMULATION CONVEYOR, and
U.S. Pat. No. 6,065,588, issued to Cotter et al. entitled CONTACT
ASSEMBLY FOR ACCUMULATION CONVEYORS, the disclosures of which are
hereby incorporated herein by reference.
[0030] Referring now specifically to FIGS. 1 and 2, an accumulation
conveyor 10 normally includes a pair of side support rails 20 and
22. Side rails 20 and 22 are joined by cross members (not shown)
positioned at longitudinally spaced intervals. A plurality of
rotatably mounted conveying rollers 25 extend between side rails 20
and 22 along the entire length of accumulation conveyor 10.
Conveying rollers 25 define a conveying surface upon which product
is transported. Conveying rollers 25 are captured within hexagonal
holes 27 formed in side rails 20 and 22. Conveying rollers 25 are
placed a preselected distance apart, preferably on three inch
centers. When so positioned, finger guards 28 may be provided
between adjacent conveying rollers 25 in order to provide
protection against a user engaging the moving components of
accumulation conveyor 10. Finger guards 28 are captured within
hexagonal holes 27 formed in side rails 20 and 22.
[0031] Accumulation conveyor 10 is divided into a plurality of
zones. In FIG. 1, only zone A and zone B are illustrated, however
it will be appreciated by those with ordinary skill in the art that
accumulation conveyor 10 may have any number of zones. An endless
drive member 30, such as drive belt, provides the mechanical force
for driving conveying rollers 25. Endless drive member 30 is driven
by a drive assembly (not shown) which imparts motion upon endless
drive member 30 in a preselected direction and moves endless drive
member 30 in a particular plane. As shown, endless drive member 30
is positioned in proximity to side support rail 20. However, it
will be recognized that endless drive member 30 may also be
positioned in proximity to side support rail 22 or any position
between the rails. Each zone of accumulation conveyor 10 includes
at least one contact assembly 50 juxtaposed with the upper portion
31 of endless drive member 30 beneath conveying rollers 25. Each
contact assembly 50 is adapted to bring upper portion 31 of endless
drive member 30 into driving engagement with conveying rollers 25
located immediately above the particular contact assembly 50. A
product sensor 35 is provided for each zone of accumulation
conveyor 10 in order to operatively control the contact assembly or
assemblies 50 for that zone, in accordance with a preselected
control scheme. Each product sensor 35 operatively engages an
actuator 37, normally a pneumatic valve, which controls the
vertically reciprocative movement of the contact assembly 50. The
details of product sensor 35, actuator valve 37, and the control
scheme by which they are operated is set forth in detail in U.S.
Pat. No. 5,540,323, which has hereinabove been incorporated by
reference. It will be recognized by those with ordinary skill in
the art that there exists a variety of product sensors and
actuators, any of which may be substituted for a product sensor 35
and actuator valve 37 without departing from the spirit and scope
of the preset invention. An example of an alternative product
sensor includes photodetectors.
[0032] Details of contact assembly 50 are disclosed in commonly
assigned U.S. Pat. No. 6,065,588, and will not be repeated herein.
In an embodiment, as shown in FIGS. 3 through 9, a wheel assembly
or contact member 79 is formed with a first or rear contact roller
84 and lead or second contact roller 86. Each contact roller 84, 86
defines a drive member engagement section. First contact roller 84
is positioned upstream in the direction of endless drive member 30.
The direction of travel of endless drive member 30 is represented
by the directional arrow in FIGS. 3 and 4. Platform 80 is formed
with a pair of posts 114 and 116. Posts 114 and 116 are formed with
a channel 118 and 118', respectively, each of which is dimensioned
to receive a respective guide member 75, 75' formed in support
member 60. Post 116 is positioned in proximity to first contact
roller 84, while post 114 is positioned in proximity to second
contact roller 86. Channel 118 is formed having a sufficiently
wider diameter than its respective post 75 to allow lateral
movement of contact member 79 with respect to movement of endless
drive member 30.
[0033] Preferably, channel 118' has a diameter only slightly larger
than its respective post 75' thereby providing a pivot to allow
contact member 79 to pivot about a vertical pivot as it moves
laterally in the plane of travel of endless drive member 30.
Contact rollers 84 and 86 are preferably crowned with their
diameters greater in their center and gradually tapering outwardly.
As a result, when endless drive member 30 becomes misaligned with
first contact roller 84, the crowned surface of first contact
roller 84 will attempt to bring endless drive member 30 into
alignment with the contact roller. Because contact member 79 is
capable of pivoting about post 75', the force created between
endless drive member 30 and the contact roller will tend to
laterally move contact member 79. If endless drive member 30
becomes more extensively misaligned along contact rollers 84 and
86, endless drive member 30 will contact one of the pair of
out-turned flanges 85 located at opposing ends of first contact
roller 84. Contact between endless drive member 30 and a flange 85
will exert a rotational force upon contact member 79, rotating
contact member 79 about guide member 75' positioned within channel
118'. As contact member 79 rotates about guide member 75', the
widened diameter of channel 118 enables contact member 79 to shift
position to compensate for the misalignment of endless drive member
30. This is accomplished by contact roller 84 moving toward
alignment with endless drive member 30 as seen by the arrows at the
right side of FIG. 4. It is also believed that the opposite
direction offset of second contact roller 86 also assists in
causing endless drive member 30 to move into alignment with contact
member 79. As illustrated by the arrows at the left side of FIG. 4,
pivoting of contact member 79 about post 75' will cause a lateral
movement of second contact roller 86 that is opposite from the
lateral movement of first contact roller 84. The crowned surface of
second contact roller 86 will cause a force tending to bring
endless drive member 30 into alignment with contact member 79. In
this manner, contact member 79 moves into alignment with endless
drive member 30 and endless drive member 30 is moved into alignment
with contact member 79. Preferably, the distance between first
contact roller 84 and post 75' is less than the distance between
second contact roller 86 and post 75'. This provides a multiplier
effect whereby a small lateral deflection of first contact roller
84 caused by misalignment of endless drive member 30, results in a
larger movement of second contact roller 86 to further assist in
pulling endless drive member 30 into alignment with contact member
79.
[0034] It can be seen that flanges 85 and the crowned configuration
of contact rollers 84 and/or 86 assist in bringing contact member
79 into alignment with endless drive member 30. However, either of
these could be used alone. Other alternatives are possible. For
example, a vertical surface such as a wheel rotated on a vertical
axis may be provided on platform 80 to contact an edge of endless
drive member 30, and rotate contact member 79 about post 75'. This
shift in position due to the rotation of contact member 79
maintains the alignment between contact rollers 84, 86 and endless
drive member 30.
[0035] In the most preferred embodiment, guide members 75, 75' have
an outer diameter of approximately 0.496 inches. Also, in the most
preferred embodiment, the diameter of channel 118 is approximately
0.605 inches. Moreover, as illustrated in FIG. 6, channel 118' is
preferably formed with a widened lower region 117 which is narrowed
in an upper region 119. The presence of a wider lower region 117
enables guide member 75 to be centered within channel 118' during
assembly, while the narrower upper region 119 holds guide member 75
securely in place. In the most preferred embodiment, upper region
119 of channel 118' has a diameter of approximately 0.505
inches.
[0036] In the most preferred embodiment, the distance between the
center lines of shafts 128, 138 is approximately 6.00 inches with
each contact roller 84, 86 having an approximate outer diameter of
1.75 inches. When so dimensioned, an accumulation conveyor 10
having conveying rollers 25 spaced on 3.00 inch centers permits
contact assemblies 50 to be positioned such that each conveying
roller 25 is driven by a particular contact roller 84, 86 of a
particular contact assembly 50 as shown in FIG. 2.
[0037] Preferably, support member 60 is formed with an orientation
member such as a rib 120. The presence of rib 120 prevents the
improper placement of contact member 79 on support member 60. As
shown in FIG. 8 when the accumulation conveyor has a drive belt
positioned in proximity to side support rail 20 with the flow of
product going in the direction indicated by the directional arrow,
rib 120 is positioned in proximity to guide member 75".
Consequently, when platform 80 is properly positioned on support
member 60 such that arm 124 is positioned proximate to back 64 of
support member 60, rib 120 will be positioned in a cavity defined
by webbing 111. An improper attempt to place platform 80 upon
support member 60 such that arm 134 is proximate to back 64 of
support member 60 will result in rib 120 contacting a stop member
150 positioned mid-height between end 104 and arm 124 (FIG. 5).
[0038] In a preferred embodiment, as shown in FIG. 9, each guide
member 75, 75' is formed having a lower region 77. A series of
circumferentially positioned barbs 78 extend from lower region 77.
During assembly, when lower region 77 of guide member 75, 75' is
positioned within a mating aperture (not shown) formed in support
member 60, barbs 78 maintain securement of guide member 75, 75'
within the aperture, and thus prevent guide member 75, 75' from
becoming loose due to the repetitive vertical forces imparted by
vertically reciprocating contact member 79.
[0039] Preferably, support member 60, contact member 79 and contact
rollers 84, 86 are each manufactured of a polymeric material. Also,
it is preferred that support member 60, contact member 79 and
contact rollers 84, 86 are manufactured by a single forming
process. In the most preferred embodiment, support member 60 and
contact member 79 are formed of a glass filled polypropylene. Most
preferably, the glass fibers are present in an amount of
approximately 30% by weight. Also, in the most preferred
embodiment, conveying rollers 84, 86 are formed of an acetal
resin.
[0040] Turning now to FIGS. 10 through 14, in another preferred
alternative embodiment, accumulation conveyor 10 includes an
endless drive member 160, which provides the mechanical force for
driving the conveying rollers. Endless drive member 160 is formed
having a protrusion 162 projecting from lower, or inner surface
164. Projection 162 is continuous, and is generally parallel to
edges 161 of drive belt 160. Top run 163 of endless drive member
160 travels in the direction indicated by the directional arrow of
FIG. 10 with product flow in an opposite direction, as also
indicated by a directional arrow. As shown most clearly in FIGS. 13
and 14, protrusion 162 has a generally tapered, pyramidal shape
with a truncated end 166. However, it will be recognized by those
with ordinary skill in the art that protrusion 162 may assume other
shapes without deviating from the spirit and scope of this
invention.
[0041] In this embodiment, a contact member 169 has a wheel
assembly or platform 170 including a central section 172, a front
section 174, and an arm 176 extending from rear surface 178.
Opposing sides 180 and 182 each have an actuator valve receiving
section 184. Arm 176, extending from rear surface 178, carries a
first pair of contact rollers 186, while front section 174 of
platform 170 carries a second pair of contact rollers 188. The top
surface of each contact roller of first pair of contact rollers 186
and second pair of contact rollers 188 reside substantially in a
single plane, above the plane defined by top surface 173 of
platform 170. First pair of contact rollers 186 and second pair of
contact rollers 188 each define a drive member engagement section.
Each contact roller 186a, 186b of first pair of contact rollers 186
is journaled to a shaft 190 extending substantially orthogonally
from arm 176. Each contact roller 188a, 188b of second pair of
contact rollers 188 is journaled to a shaft 198 extending
substantially orthogonally from front section 174 of platform 170.
First pair of contact rollers 186 and second pair of contact
rollers 188 are each generally axially aligned. Each contact roller
186a, 186b of first pair of contact rollers 186 has an inner
surface 187, defining a distance 194 therebetween. Additionally,
each contact roller 188a, 188b of second pair of contact rollers
188 has an inner surface 189, defining a space 196
therebetween.
[0042] Platform 170 is formed with a pair of posts 202 and 204.
Each post 202, 204 is formed with a channel dimensioned to receive
a guide member 206, 206' formed in support member 205. Post 202 is
positioned in proximity to first pair of contact rollers 186, while
post 204 is positioned in proximity to second pair of contact
rollers 188. The channel formed within post 204 has a wider
diameter than the channel formed in post 202.
[0043] In operation, platform 170 is placed upon support member 205
with post 202 being received by guide member 206, and post 204
being received by guide member 206'. Thus, as shown in FIG. 10,
first pair of contact rollers 186 are positioned first in the
direction of travel of endless drive member 160. When platform 170
is vertically reciprocated by diaphragm 74, first pair of contact
rollers 186 and second pair of contact rollers 188 engage inner
surface 164 of top run 163 endless drive member 160 and thus urge
endless drive member 160 into engagement with conveying rollers 25.
Protrusion 162 of endless drive member 160 is positioned in the
space 194 defined between first pair of contact rollers 186 and the
space 196 defined between second pair of contact rollers 188, with
truncated end 166 of protrusion 162 residing a preselected distance
above top surface 173 of platform 170. The distance between contact
rollers 186a, 186b of first pair of contact rollers 186 is slightly
larger than the width of protrusion 162 and less than the distance
between contact rollers 188a, 188b of second pair of contact
rollers 188.
[0044] During operation, if endless drive member 160 becomes
misaligned, surface 167 or 167' of protrusion 162 will contact an
inner surface 187 of a contact roller 186a or 186b of first pair of
contact rollers 186. Contact between protrusion 162 and contact
rollers 186a, 186b effects the lateral movement of platform 170
with respect to the plane of travel of endless drive member 160.
Specifically, contact between protrusion 162 and contact rollers
186a, 186b pivots or rotates platform 170 about the vertical axis
of guide member 206. The widened diameter of the channel of post
204 enables platform 200 to move in a lateral direction to the
direction of endless drive member 160, and thereby maintain the
alignment between first pair of contact rollers 186, second pair of
contact rollers 188, and endless drive member 160. Specifically,
contact between protrusion 162 and first pair of contact rollers
186 pivots or rotates the position of platform 170 so that first
pair of contact rollers 186 and second pair of contact rollers 188
remain centered on top run 163 of endless drive member 160. This
pivotal movement of contact member 169 causes contact rollers 188a
and 188b to become laterally offset with respect to endless drive
member 160. The lateral static friction between rollers 188a, 188b
and endless drive member 160 tends to draw endless drive member 160
back into alignment with contact member 169. Diaphragm 74 does not
pivot with platform 170, but remains in its vertical orientation
and supported within cavity 72.
[0045] Support member 205 is structurally similar to support member
60 except for the position of rib 120. In support member 205, rib
120 is positioned proximate to guide member 206, so as to prevent
the improper placement of platform 170 on support member 205. Also,
posts 202, 204 have the same respective shapes as posts 75, 75' and
sit within channels having the same respective shapes as channels
118 and 118'. Also, the relative spacing between contact rollers
186, 188 and posts 202, 204 are generally the same as the spacing
between contact rollers 84, 86 and post 118, 118'.
[0046] In a preferred alternative embodiment, an endless drive
member sensor 200 (FIG. 10) which senses the lateral position of
endless drive member 30 is employed to monitor the position of
endless drive member 30. Endless drive member sensor 200 is
operably interconnected to one or more contact assemblies 50 by any
means commonly utilized in the art. In the event endless drive
member 30 becomes misaligned, a signal is sent from sensor 200 to
contact assembly 50 resulting in the rotation or pivotal movement
of contact member 79, 169 in order to maintain alignment between
endless drive member 30 and contact member 79, 169. Endless drive
member sensor 200 may be any sensor commonly employed in the
art.
[0047] With reference to FIG. 15, an accumulation conveyor 250
includes an endless drive member 260 traveling in a particular
direction, indicated by the directional arrow, and within a plane.
Accumulation conveyor 250 includes one or more contact assemblies
262 configured to selectively reciprocally engage endless drive
member 160 perpendicular to the plane of FIG. 15. Contact assembly
262 includes a sensor 264 which senses the misalignment of endless
drive member 260 within the plane of travel, and a coupling 270
which transfers misalignment sensed by sensor 264 to an aligning
member 266 configured to reposition endless drive member 260 into
alignment with contact assembly 262 when sensor 264 senses
misalignment of endless drive member 260. In the illustrated
embodiment, sensor 264 is a roller 84, 186 which senses
misalignment of endless drive member 260 and repositions aligning
member 266 by pivoting platform 170 about pivot 268. This laterally
deflects and somewhat rotates aligning member 266 with respect to
endless drive member 260. This motion of aligning member 266 causes
endless drive member 260 to move left as viewed in FIG. 15.
Aligning member 266 thus moves in the plane of endless drive member
260 to realign contact assembly 262 with endless drive member
260.
[0048] As discussed above, sensor 264 can be either first contact
roller 84 or first pair of contact rollers 186, while aligning
member 266 is either second contact roller 86 or second pair of
contact rollers 188. In those embodiments, sensor 264 causes
aligning member 266 to pivot or rotate about a pivot 268 to realign
contact assembly 262 with endless drive member 260. However, sensor
264 may also be an electronic or mechanical sensor, such as for
example, a photoeye, carried by, or in proximity to, contact
assembly 262, and in operational connection therewith, which issues
a signal to an electronic or mechanical actuator that is employed
to move aligning member 266 and thus realign contact assembly 262
with endless drive member 260. Aligning member 266 may be moved in
a purely rotational fashion to realign endless drive member 260
rather than the illustrated combination of rotation and lateral
deflection.
[0049] Changes and modifications in the specifically described
embodiments can be carried out without departing from the
principles of the invention. For example, although the drive member
engagement section has been described as either contact rollers or
pairs of contact rollers, it will be understood by those with
ordinary skill in the art that drive member engagement section may,
for example, take the form of a flat surface such as that disclosed
in U.S. Pat. No. 5,540,323, the disclosure of which has been
incorporated herein by reference. Also, endless drive member 30 may
be a padded chain, a linked belt, or continuous belt of any cross
sectional configuration. Therefore, the present invention is
intended to be limited only by the scope of the appended claims, as
interpreted according to the principles of patent law including the
doctrine of equivalents.
* * * * *