Modular conveying assembly having roller cradles

Description of equivalent WO 2004078619 A1

MODULAR CONVEYING ASSEMBLY HAVING ROLLER CRADLES

CROSS REFERENCES TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No.

60/451,520 filed on March 3, 2003 and U.S. Provisional Patent Application No. 60/529,539 filed

December 15, 2003.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

[0002] Not Applicable.

Background Of The Invention

[0003] The present invention relates to modular conveying assemblies, and more particularly

to a modular conveyor belt or chain including roller cradle attachments.

[0004] Modular conveyor belts and chains are formed from interconnected modules that are

supported by a frame and driven to transport a product. Each module has a support surface which

supports the product as the belting or chain is being driven along the frame. Modules adjacent

each other are connected to each other by hinge pins inserted through meshing eyes extending

from adjacent links in the direction of the belt travel.

[0005] Modular belts can transport products in the direction of belt travel, but have difficulty

transferring a product, especially a high friction product, onto or off of the belt. Moreover, high

friction products can easily damage the belt if the product is transferred onto the chain from a

direction other than the chain direction of travel, hi addition, accumulation of a product on the

surface of the chain can easily damage the belt or product being conveyed. [0006] A conveyor belt formed from roller cradles is disclosed in U.S. Pat. No. 4,231,469

issued to Arscott. The cradles support rollers that extend above the cradle for rolling contact with

an object being conveyed to reduce friction between the belt and the object. Unfortunately,

assembling the roller in the cradle is difficult requiring insertion of the roller into the cradle, and

then slipping an axle or two stub axles through holes formed through the cradle walls and into

the roller. The axle must then be secured to prevent it from slipping out of one of the holes

formed in the cradle wall.

Summary Of The Invention

[0007] The present invention provides a modular conveying assembly for conveying an

object. The assembly includes a plurality of chain modules assembled in an edge to edge relation

to form a continuous belt. At least one hinge pin joins adjacent chain modules, and pivotally

connects the adjacent modules in the direction of belt travel. At least one cradle adjacent at least

one of the modules is retained by the at least one pin. A roller is supported by the cradle and, in

one embodiment, is engageable with the object to reduce friction between the belt and the object.

[0008] In another embodiment, the cradle includes a first half including a first hinge element.

A second half including a second hinge element is spaced from the first hinge element and

defines a space therebetween. A shaft extends between the first and second halves through the

space defined by the first and second hinge elements. The roller is retained by the shaft in the

space for engaging the object.

[0009] A general objective of the present invention is to provide a modular conveying

assembly that can convey high friction objects without severely damaging the objects or the assembly. This objective is accomplished by providing a roller cradle in the assembly that

supports a roller that reduces friction between the object and the conveying assembly.

[0010] Another objective of the present invention is to provide a cradle that is easy to

assemble. This objective is accomplished by forming a cradle from two halves defining a space

therebetween and supporting the roller on the space.

[0011] This and still other objectives and advantages of the present invention will be

apparent from the description which follows. In the detailed description below, preferred

embodiments of the invention will be described in reference to the accompanying drawings.

These embodiments do not represent the full scope of the invention. Rather the invention may be

employed in other embodiments. Reference should therefore be made to the claims herein for

interpreting the breadth of the invention.

Brief Description Of The Drawings

[0012] Fig. 1 is a perspective view of a modular conveying assembly incorporating the

present invention;

[0013] Fig. 2 is a partially exploded perspective view of the modular conveying assembly of

Fig. 1;

[0014] Fig. 3 is a perspective, exploded view of the cradle shown in Fig. 1;

[0015] Fig. 4 is a perspective, exploded view of another embodiment of a cradle for use in

the belt of Fig. 1;

[0016] Fig. 5 is a perspective, exploded view of yet another embodiment of a cradle for use

in the belt of Fig. 1; [0017] Fig. 6 is a perspective view of another embodiment of a modular conveying assembly

incorporating the present invention;

[0018] Fig. 7 is a partially exploded perspective view of the modular conveying assembly of

Fig. 6;

[0019] Fig. 8 is a perspective, exploded view of the cradle shown in Fig. 6;

[0020] Fig. 9 is a perspective, exploded view of another embodiment of a cradle for use in

the assembly of Fig. 6;

[0021] Fig. 10 is a perspective, exploded view of yet another embodiment of a cradle for use

in the assembly of Fig. 6;

[0022] Fig. 11 is a perspective, exploded view of yet another embodiment of a cradle for use

in the assembly of Fig. 6;

[0023] Fig. 12 is a perspective view of yet another embodiment of a cradle for use in the

assembly of Fig. 1;

[0024] Fig. 13 is an exploded view of the cradle of Fig. 12;

[0025] Fig. 14 is a perspective, exploded view of yet another embodiment of a cradle for use

in the assembly of Fig. 1;

[0026] Fig. 15 is a side elevation view of the cradle of Fig. 10;

[0027] Fig. 16 is a side elevation view of another embodiment of the cradle of Fig. 10

showing the roller extending above and below the cradle;

[0028] Fig. 17 is side elevation view of another embodiment of the cradle of Fig. 10 showing

the roller extending below the cradle; [0029] Fig. 18 is a perspective view of an embodiment of a cradle having an angled shaft for

use in a modular conveying assembly;

[0030] Fig. 19 is an exploded view of the cradle of Fig. 18;

[0031] Fig. 20 is a perspective view of an embodiment of a cradle having a roller ball for use

in a modular conveying assembly; and

[0032] Fig. 21 is an exploded view of the cradle of Fig. 20.

Detailed Description Of Preferred Embodiments

[0033] A modular conveyor assembly forming a belt 10, shown in Figs. 1 and 2, includes a

plurality of chain modules 12 assembled in an edge to edge relation to form the continuous belt

10. Hinge pins 14 join adjacent modules 12, and pivotally connect the adjacent modules 12 in the

direction of belt travel. Cradles 16 retained by the pins 14 between modules 12 in a row support

transverse cylindrical rollers 17 that rotatably engage an object being conveyed by the belt 10 to

reduce friction between the belt 10 and the object. A row of modules 12 is a plurality of the

modules 12 disposed between adjacent hinge pins 14. The rollers 17 in this embodiment are

considered transverse rollers because they have an axis of rotation aligned in the direction of belt

travel (indicated by the arrow in Fig. 2) and convey an object transverse to the direction of belt

travel. Advantageously, if the module 12, cradle 16, or roller 17 is damaged, only the damaged

component need be replaced.

[0034] The modules 12 are preferably formed using methods known in the art, such as

injection molding, from materials known in the art, such as acetal, polyethylene, polypropylene,

nylon, and the like. Each module 12 includes a body 18 having a top surface 20 surrounded by a leading edge 22 and trailing edge 24 joined by side edges 26. Advantageously, the top surface 20

can engage objects being conveyed by the belt 10.

[0035] The module body 18 has a width which is defined by the distance between the side

edges 26, and a length which is defined by the distance between the longitudinal leading and

trailing edges 22, 24. Leading edge hinge members 32 extending forwardly from the leading

edge 22 of the module body 18 include coaxial openings 34. The opening 34 formed in each

leading edge hinge member 32 is coaxial with the opening 34 in the adjacent leading edge hinge

member 32 for receiving the hinge pin 14. Trailing edge hinge members 36 extending rearwardly

from the trailing edge 24 also include coaxial openings 38. As in the leading edge hinge member

openings 34, the opening 38 formed in each trailing edge hinge member 36 is coaxial with the

opening in the adjacent trailing edge hinge member 36 of a module 12.

[0036] The forwardly extending leading edge hinge members 32 of one module 12 intermesh

with trailing edge hinge members 36 extending rearwardly from an adjacent module 12. When

the intermeshing hinge members 32, 36 are aligned, the openings 34, 38 in the aligned hinge

members 32, 36 are aligned to receive the hinge pin 14 which pivotally joins the modules 12

together. Although hinge members 32, 36 extending rearwardly and forwardly from the leading

and trailing edges 22, 24, respectively, is shown, the hinge members 32, 36 can also extend in

other directions, such as downwardly, proximal the respective edges 22, 24 without departing

from the scope of the present invention.

[0037] The cradles 16 are retained by the hinge pins 14, and are not attached directly to the

modules 12. Preferably, the cradles 16 are preferably formed using methods known in the art,

such as injection molding, from materials known in the art, such as acetal, polyethylene, polypropylene, nylon, and the like. However, the cradles can be formed using other materials,

such as metal, without departing from the scope of the invention.

[0038] In the embodiments disclosed in Figs. 1-5, each cradle 16 has two parallel side walls

40, 42 and two opposing hinge members 44, 46. The hinge members 44, 46 define a space, or

opening, therebetween that is framed by the hinge members 44, 46 and side walls 40, 42. A shaft

48 extending tlirough the opening between the hinge members 44, 46 rotatably supports the roller

17 disposed in the opening. The hinge pins 14 pivotally joining the adjacent modules 12 slip into

apertures 50, 52 formed through the cradle hinge members 44, 46 that are aligned with the

module openings 34, 38 to fix the cradle 16 relative to the adjacent modules 12. The position and

number of cradles 16 in a belt 10 is customizable, and depends upon the conveyor belt

application.

[0039] Each cradle 16 is formed from two separately formed halves 54, 56 to simplify

assembly. Each half 54, 56 includes one of the side walls 40, 42 having one end 58 joined to one

of the hinge members 44, 46. The opposing end 60 of each side wall 40, 42 abuts an end of the

other hinge member 44, 46, and includes an aperture 62 for receiving the hinge pin 14 extending

through the other hinge member 44, 46 joining the adjacent modules 12.

[0040] The shaft 48 extends between the hinge members 44, 46 tlirough the opening, and is

substantially parallel and adjacent to the side walls 40, 42 of the assembled cradle 16, such that

the shaft is aligned with the direction of belt travel. A shaft opening 64 formed in each hinge

member 44, 46 opens toward the other hinge member 44, 46 of the assembled cradle 16, and

receives one end of the shaft 48. The shaft can be formed from any known material, such as plastic, metal, and the like. The shaft material is dependent upon the shaft length and forces that

will be exerted upon the shaft 48 in the intended use of the belt 10.

[0041] In the embodiment disclosed in Figs. 2 and 3, the shaft 48 is formed from two shaft

halves 66, 68. Each shaft half 66, 68 extends from one of the hinge members 44, 46, and defines

a shaft cross section that is semicircular, such as a half circle, to form the shaft 48 having a

circular cross section when the cradle 16 is assembled from the cradle halves 54, 56. The half

shaft ends can be retained in the hinge member shaft openings 64 using methods known in the

art, such as a friction fit, adhesives, and the like, to simplify assembly. Moreover, if the shaft 48

is not formed from two halves, such as disclosed in Fig. 4, one end of the shaft 48 can be retained

in one of the hinge member shaft openings 64, or formed as an integral part of the cradle half 54,

to simplify assembly. However, once the cradle halves 54, 56 are assembled together to form the

cradle 16, the shaft cannot slip out of the shaft openings 64, and a means for retaining the shaft

48 in only one shaft opening 64 is not necessary, such as shown in Fig. 5.

[0042] Referring back to Figs. 1-3, the roller 17 is supported by the shaft 48 in the frame

opening. At least a portion of the roller 17 extends above the cradle 16 to engage the object being

conveyed by the belt 10. Preferably, the roller 17 is molded from a plastic, and includes a

throughhole 74 formed therethrough for receiving the shaft 48. Advantageously, if the roller 17

extends above the cradle 16 to engage an object being conveyed, the roller 17 rotates about the

shaft 48 to minimize friction between the belt 10 and object being conveyed.

[0043] The cradle 16 is assembled by slipping the distal ends 70, 72 of each shaft half 66, 68

into opposite ends of the roller throughhole 74. The distal ends 70, 72 are then slipped into the

opposing hinge member shaft opening 64 such that each end of the shaft 48 is supported by one of the hinge members 44, 46. An end of each hinge member 44, 46 of each cradle half 54, 56

abuts a face of the opposing cradle half side wall opposing end 60, such that the hinge member

aperture 50, 52 is aligned with the aperture 62 formed in the opposing cradle half side wall

opposing end 60. A hinge pin 14 joining the adjacent modules 12 is then slipped through the

hinge member aperture 50 of one cradle half 54 and the side wall aperture 62 of the other cradle

half 56, and another hinge pin 14 is slipped through the hinge member aperture 52 of the other

cradle half 56 and the side wall aperture 62 of the one cradle half 54 to prevent the cradle halves

54, 56 from separating.

[0044] In another embodiment of the present invention shown in Figs. 6-8, a modular

conveyor belt 100 includes a cradle 116 supporting a low back pressure roller 117. The roller 117

shown in Figs. 6-8 is considered a low back pressure roller because they have an axis of rotation

transverse to the direction of belt travel and convey an object in the direction of belt travel. As in

the transverse roller embodiments disclosed in Figs. 1-5, the cradle 116 disclosed in Figs. 6-8 is

formed from two halves 154, 156. Each half 154, 156 includes a hinge member 144, 146 and a

side wall 140, 142, respectively. As opposed to the transverse roller embodiments, however, the

shaft 148 shown in Figs. 6-8 extends between the side walls 140, 142 in a direction transverse to

the direction of belt travel to rotatably mount the low back pressure roller 117. The shaft 148 is

formed as an integral part of the side wall 140 of one half 154, and has a distal end 149 that is

received in the shaft opening 164 formed in the side wall 142 of the other half 156. Of course,

the shaft 148 can be formed from two half shafts 166, 168, as disclosed in Figs. 9 and 11, and the

shaft 148 can be press fit in the shaft openings 164 formed in both side walls 140, 142, as shown

in Fig. 10, without departing from the scope of the invention. [0045] In the embodiment disclosed in Fig. 11, opposing ends 160 of each side wall 140, 142

have a dovetail shape that is received in complementary notches 161 foπned in the hinge element

144, 146 forming part of the opposing cradle half 154, 156. The dove tailed side wall end 160

interlocks with the notch 161 prevents the cradle halves 154, 156 from separating in the direction

of belt travel due to spacing fluctuations between the hinge pins 14 joining the cradle 116 to the

modules 12.

[0046] In yet another embodiment of the present invention shown in Figs. 12-14, cradles

216, 316 supporting transverse rollers 217, 317 are formed from cradle halves 254, ^'256, 354, 356

without side walls. The cradles 216, 316 include a shaft 248 extending between hinge elements

244, 246, 344, 346. As shown in Fig. 13, the hinge elements 244, 246 include shaft openings 264

for supporting the shaft ends. Although a shaft formed from shaft halves 266, 268 is shown in

Fig. 13, shafts 48, such as disclosed in Figs. 4 and 5 can also be used without departing from the

scope of the invention. In the embodiment disclosed in Fig. 14, each hinge element 344, 346

includes a pair of meshing eyes 347 for receiving the hinge pins 14.

[0047] In yet other embodiments, shown in Figs. 15-17, cradles including a shaft supporting

a roller is positioned to extend a portion of the roller above the cradle (shown in Fig. 15), below

the cradle (shown in Fig. 17), or above and below the cradle (shown in Fig. 16). As shown in

Fig. 15, a version of the roller cradle 116 shown in Fig. 10 for use in the belt 100 shown in Fig.

6, includes a shaft formed from shaft halves (only shaft half 166 is shown) and defining a shaft

axis 176. The shaft axis 176 is located above a midpoint 170 between cradle upper and lower

edges 172, 174, such that a portion of the roller 117 supported by the shaft extends above the

upper edge 172 of the cradle 116. Advantageously, a cradle 116 having a portion of the roller 117 extending above the cradle 116, such ^.own in Fig. 15, allows an object to move relative to

the cradle 116, and thus the belt 100, to minimize back pressure.

[0048] In Fig. 16, a cradle 116a for use in the belt 100 shown in Fig. 6, includes a shaft

formed from shaft halves (only shaft half 166 is shown) and defining a shaft axis 176. In Fig. 16,

the shaft axis 176 is located substantially at the midpoint 170 between the cradle upper and lower

edges 172, 174 and a roller 117 supported by the shaft has a diameter larger than the distance

between the cradle upper and lower edges 172, 174, such that a portion of the roller 117 extends

above the roller cradle upper edge 172 and a portion of the roller 117 extends below the cradle

lower edge 174. Advantageously, an object being conveyed by a belt including the cradles 116a

having rollers 117 extending above and below the cradle 116a, such as shown in Fig. 16, can be

accelerated in the direction of conveyor travel by engaging the portion of the rollers 117

extending below the cradle lower edge 174 with a surface that rotates the rollers 117 to propel the

object supported by the portion of the roller 117 extending above the cradle upper edge 172.

[0049] In Fig. 17, a cradle 116b for use in the belt 100 shown in Fig. 6, includes a shaft

formed from shaft halves (only shaft half 166 is shown) and defining a shaft axis 176. In Fig. 17,

the shaft axis 176 is located below the midpoint 170 between the cradle upper and lower edges

172, 174, such that a portion of the roller 117 supported by the shaft extends below the lower

edge 174 of the cradle 116b. Advantageously, friction between a belt and a supporting surface

can be minimized by providing the cradle 116b having a roller 117 extending below the cradle

lower edge 174, such as shown in Fig. 17, that engages the supporting surface.

[0050] In still another embodiment of the present invention shown in Figs. 18 and 19, a roller

cradle 416 for use in the belt 10 shown in Fig. 1 and the belt 100 shown in Fig. 6 includes a shaft 448 extending between shaft halves 454, 456 at an angle A defined by the cradle side walls 440,

442 and the shaft 448, such that the shaft 448 is aligned in a direction between the direction of

belt travel and the direction transverse to the direction of belt travel. The shaft 448 rotatably

supports a roller 417 which can support an object being conveyed. The angled shaft 448 allows

the object to be transferred onto and off of a belt including the cradle 416 at an angle generally

corresponding to angle A.

[0051] In yet another embodiment shown in Figs. 20 and 21, a cradle 516 for use in the belt

10 shown in Fig. 1 and the belt 100 shown in Fig. 6 supports a spherical roller 517. The cradle

516 includes lower and upper shelves 521, 523 extending from each shaft half 554, 556 to

rotatably secure the roller 517 between the shaft halves 554, 556. The lower shelves 521 extend

beneath the ball diameter, and in the embodiment shown in Figs 20 and 21 beneath the roller

517, to support the roller 517. The upper shelves 523 extend toward the roller 517 above the ball

diameter to secure the roller 517 relative to the lower shelves 521 and allow a portion of the

roller 517 to extend above the cradle 516 and support an object being conveyed. Although

shelves are preferred, other structure can be provided, such as shafts or other retention member,

extending between the cradle halves to rotatably secure the roller relative to the cradle without

departing from the scope of the invention. Moreover, the roller 517 and shelves can be sized,

such that the roller extends above, below, or above and below the cradle 516 without departing

from the scope of the invention.

[0052] While there has been shown and described what are at present considered the

preferred embodiments of the invention, it will be obvious to those skilled in the art that various

changes and modifications can be made therein without departing from the scope of the invention defined by the appended claims. For example, in the embodiments disclosed in Figs. 1-5, both cradle halves include a side wall. However, one cradle halve can be provided without a side wall without departing from the scope of the invention. In addition, the side walls in the embodiments including side walls engage or abut the opposing hinge member, in other embodiments, cradle halves can be provided with side walls that do not touch any part of the other cradle half without

departing from the scope of the invention.