Roller conveyor gap stoppers

Abstract

In one aspect, the gap stopper comprises a body having an upper stopper portion and leg portions of the body connected to the upper stopper portion at longitudinally spaced locations. The leg portions of the body have an initial undeflected configuration, wherein at least one of the leg portions has a first orientation relative to the upper stopper portion. The leg portions of the body have an operational configuration, wherein the body is positioned in a gap between rollers, wherein at least one of the leg portions has a first orientation relative to the upper stopper portion. The upper stopper portion has an upper contact portion, and the leg portions have a lower contact portion for contacting the rollers. The body further comprises an outer surface portion intermediate the upper contact portion and the lower contact portion, the outer surface portion being configured to be in clearance with the rollers.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 081,410, filed on September 22, 2020, which is hereby incorporated by reference in its entirety. Technical Field

[0003] The present disclosure relates to roller conveyors, and more particularly to gap blocks that block gaps between rollers of a roller conveyor. Background Art

[0004] Roller conveyors are used to transfer items from one location to another, such as packages within a packaging distribution center and products in a manufacturing environment. Roller conveyors may utilize rollers that are rotatably supported in fixed positions. The rollers contact the items on the roller conveyor to transfer the items downstream along the roller conveyor. Roller conveyors have gaps between the rollers to allow the rollers to rotate without contacting each other.

[0005] Sometimes, an object may fall through one of the gaps between the rollers and land in the area below. Objects falling through the gaps between the rollers can damage the underlying structure, such as the belts that jam the drive rollers and related mechanisms. As another example, a portion of an object, such as the corner of a box, can become lodged in the gaps between the rollers. These situations can adversely affect the operation of the roller conveyor and the surrounding environment. Summary of the Invention

[0006] In one aspect of the present disclosure, a gap blocker for a roller conveyor having rollers and a gap between the rollers is provided. The gap blocker includes a body to be positioned in the gap between the rollers, an upper blocking portion of the body for preventing articles carried by the rollers from falling through the gap, and leg portions of the body, the leg portions being connected to the upper blocking portion at longitudinally spaced positions such that the leg portions have a space extending therebetween in the longitudinal direction.

[0007] The leg portions of the body have an initial, undeflected configuration, wherein at least one of the leg portions has a first orientation relative to the upper barrier portion. To facilitate advancement of the body into the gap, the leg portions of the body can be offset relative to each other to reduce the distance across the space between the leg portions. For example, one of the leg portions can be moved toward the other leg portion, or the two leg portions can be moved toward each other. The leg portions of the body have an operational configuration, wherein the body is in the gap. When the leg portions are in the operational configuration, at least one of the leg portions has a first orientation relative to the upper barrier portion, similar to when the leg portions are in the initial, undeflected configuration.

[0008] The upper barrier portion has an upper contact portion, and the leg portion has a lower contact portion for contacting the roller as the roller rotates to convey articles in a downstream direction. In some applications, the lower contact portion is generally spaced from the roller and contacts the roller only as needed to limit rattling or other movement of the gap barrier in the gap. The limited contact between the lower contact portion and the roller reduces stress and wear on the gap barrier and can provide a longer operating life for the gap barrier.

[0009] The body further includes an outer surface portion extending along the roller intermediate the upper and lower contact portions. The outer surface portion of the body is configured to create clearance with the roller when the body is in the gap and the leg portions are in the operative configuration. In this manner, the outer surface portion of the body reduces the contact area between the body and the roller, which reduces the frictional resistance of the gap barrier to the rotation of the roller. Reducing the frictional resistance of the gap barrier to the rotation of the roller minimizes energy loss in the roller conveyor attributable to the gap barrier.

[0010] The present disclosure also provides a gap stopper comprising a body to be positioned in a gap between rollers of a roller conveyor. The body comprises an upper blocking portion having an upstream contact portion and a downstream contact portion configured to contact the roller above the narrowest portion of the gap, and a resilient lower portion of the body having an upstream lower protrusion and a downstream lower protrusion for contacting the roller. The upstream and downstream lower protrusions are configured to form a limited contact area with the roller, which minimizes the frictional resistance of the resilient lower portion of the body to the rotation of the roller. In one approach, the upstream and downstream lower protrusions are configured to form a tight running fit with the roller.

[0011] The elastic lower portion of the body has a deflected configuration in which the elastic lower portion is narrower than the narrowest portion of the gap to allow the elastic lower portion of the body to be advanced through the narrowest portion of the gap and into an operative position below the narrowest portion of the gap. The elastic lower portion of the body has an undeflected configuration in which the upstream and downstream lower protrusions are below the narrowest portion of the gap. Because the elastic lower portion of the body is undeflected when the protrusions contact the roller below the narrowest portion of the gap, the protrusions are positioned to resist chatter and other movement of the gap blocker while preventing the roller from being tightly clamped by the gap blocker between the protrusions and the upstream and downstream contact portions of the upper blocking portion of the gap blocker body. The limited clamping of the gap blocker against the roller contributes to low-friction contact between the gap blocker and the roller.

[0012] The resilient lower portion of the body has upstream and downstream clearance surface portions located along the height of the body intermediate the upper barrier portion of the body and the upstream and downstream lower protrusions. The upstream and downstream surface portions of the resilient lower portion of the body are configured to be in clearance with the roller when the body is in the operating position, which further reduces the contact area of ​​the gap blocker on the roller and reduces the frictional resistance of the gap blocker to rotation of the roller. The gap surface portions being in clearance with the roller means that the gap surface portions do not engage the roller when the gap blocker is installed and during operation of the roller conveyor, thereby maintaining the gap surface portions spaced apart from the adjacent roller even when the roller rotates during operation of the roller conveyor. Similarly, by providing a gap surface portion that does not engage the adjacent roller when installed or during operation of the roller conveyor, the gap blocker is configured to minimize frictional engagement with the roller. If a heavy article contacts the gap barrier and causes one or both gap surface portions to temporarily contact one or both rollers, the resilient lower portion returns the gap surface portions to gap with the rollers once the article has been conveyed downstream of the gap barrier.

[0013] In another aspect of the present invention, a roller conveyor is provided that includes rollers, a gap between the rollers, and a drive member extending around the rollers to transmit rotation of one of the rollers to the other roller. The drive member, such as an O-ring, has an upper portion and a lower portion (or upper and lower runs) extending across the gap and spaced apart from each other by a distance therebetween.

[0014] The roller conveyor also includes a gap blocker supported in the gap by the first and second rollers. The gap blocker has an upper blocker portion above the narrowest portion of the gap, a lower portion below the narrowest portion of the gap, and an intermediate portion extending into the narrowest portion of the gap. The gap blocker has a height that is less than the outer diameter of either roller and less than the distance between the upper and lower portions of the drive member. Whether the gap blocker is mounted so that a portion of the gap blocker extends in the opening formed by the upper and lower portions of the drive member and the rollers, or is laterally offset into the opening during operation of the roller conveyor, the gap blocker can have clearance from the drive member. In this way, the gap blocker protects the gap from conveyed items falling through it while avoiding interference with the drive member that rotates the rollers. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a perspective view of a roller conveyor system including rollers rotated by a drive belt to convey articles in a longitudinal downstream direction and a gap barrier extending transversely in a gap between the rollers;

[0016] Figure 2 It is along Figure 1a cross-sectional view taken along line 2-2 in Figure 2 showing one of the gap barriers in the gap between the upstream and downstream rollers, the gap barrier having an upper surface that is recessed from the top of the rollers to facilitate movement of articles across the rollers without contacting the gap barrier;

[0017] Figure 3 yes Figure 2 An elevational view of a gap barrier showing an upper barrier portion and a lower leg portion of the gap barrier;

[0018] Figure 4 yes Figure 3 A perspective view of a gap barrier showing a thicker downstream leg portion and a thinner upstream leg portion of the gap barrier;

[0019] Figure 5 When Figure 2 An elevational view of the rollers and the gap blocking member when the gap blocking member is inserted into the gap between the rollers;

[0020] Figure 6 is a perspective view of another gap barrier having a pair of upstream leg portions separated by an opening;

[0021] Figure 7 is an elevational view of another gap barrier having the same lower leg portion and mountable in a gap between rollers with either leg portion contacting an upstream roller associated with the gap;

[0022] Figure 8 yes Figure 7 a perspective view of a gap barrier showing a leg portion depending from an outer roller engaging portion of the gap barrier;

[0023] Figure 9 is an elevational view of another gap blocker having a leg portion with a substantially straight portion depending from an upper blocking portion of the gap blocker;

[0024] Figure 10 is an elevational view of another gap barrier having a distinct contact surface for contacting a roller;

[0025] Figure 11 is an elevational view of another gap blocking member, the gap blocking member being symmetrical about the central axis;

[0026] Figure 12 is an elevational view of a portion of a roller conveyor including rollers, a drive member connecting the rollers, and a gap barrier sized to fit within an opening formed by the rollers and the drive member;

[0027] Figure 13is an elevational view of a pair of rollers when a gap stopper is inserted into a gap between the rollers;

[0028] Figure 14 is Figure 13 Elevation view of the roller and gap stopper after the gap stopper has been installed in the gap. DETAILED DESCRIPTION

[0029] Reference Figure 1 , a conveyor system 10 is provided that includes a roller conveyor 12 having rollers 14 that are driven by a drive belt 16 underneath to rotate in a direction 18 and transfer articles in a longitudinal downstream direction 20. The drive belt 16 is looped around a head pulley and a tail pulley ( Figure 1 1 and 2. The rollers 14 are driven by a motor 16A (not shown). The drive belt 16 is driven in a direction 22 to engage a lower portion of the rollers 14, thereby producing rotation in a direction 18. The rollers 14 are rotatably mounted to a track 24 of a conveyor support structure 26 at a fixed position relative to the track 24, so that the rollers 14 are stationary in the longitudinal direction 20 during operation of the roller conveyor 12.

[0030] Reference Figure 1 and Figure 2 , the rollers 14 have gaps 34 between adjacent upstream and downstream pairs of rollers 14. The conveyor system 10 includes gap blocks or gap blocking members 40 in the gaps 34 between adjacent rollers 14. The gap blocks 40 prevent articles from becoming lodged in the gaps 34 or falling through the gaps 34. The gap blocks 40 also limit debris (such as dust, dirt, and particles) from the conveyed articles from falling into the area below the rollers 14 (such as the area on the drive belt 16). Roller conveyors (such as the conveyor system 10) typically have rollers 14 that have the same outer diameter and spacing between the rollers 14 so that the gap 34 between one pair of rollers 14 does not vary relative to the gap 34 between the other pair of rollers 14. This is in contrast to conveyor belt systems that have gaps between conveyor belts where the thickness of the belts may vary over time or as different belts are used, causing the size of the gaps between the conveyor belts to change. The gap blocker 40 can thus have tighter tolerances than some transfer devices used to transfer articles between conveyor belts because the gap blocker 40 has limited engagement with the roller 14, rather than resiliently clamping the adjacent upstream and downstream rollers 14 to hold the gap blocker 40 in the gap 34. The tighter tolerances of the gap blocker 34 allow the gap blocker 40 to have a rotational engagement with the roller 14, which reduces the frictional resistance transmitted by the gap blocker 40 to the roller 14 and improves the efficiency of the motor 16A in driving the drive belt 16.

[0031] like Figure 2As shown in , the gap barrier 40 has a body 42 having an upper barrier portion 44 and a lower portion 46, the lower portion 46 including an upstream lower member (such as an upstream leg portion 48) and a downstream lower member (such as a downstream leg portion 50). In one embodiment, the body 42 of the gap barrier 40 has a one-piece structure, wherein the gap barrier 40 is a single, integral member of the same material. For example, the gap barrier 40 can be formed by extruding a material, such as a plastic material, to form a predetermined length of the gap barrier 40 extending between the lateral sides 43A, 43B of the gap barrier 40. In another embodiment, the gap barrier can be a single part made of multiple materials. For example, the body 42 can include a first material for the frame of the body 42 and a second material with low friction to contact the roller. An example of this is that the first material can be UHMW polyethylene and the second material can be The multiple materials can be joined, for example, by an overmolding step, wherein a first material is injection molded in a first mold to form the frame of the body 42. The frame of the body 42 is then inserted into a second mold, wherein a second material is injection molded in the second mold and bonded to the frame. In another approach, the body 42 can be formed from a plurality of parts that are mechanically connected, for example by snap-fits and / or mating protrusions and recesses. The gap blocker 40 has a cross-section perpendicular to the length that is consistent throughout the length. The phrase "consistent throughout the length" is intended to mean that the cross-section of the gap blocker 40 perpendicular to the length is the same throughout the length of the gap blocker 40.

[0032] In other embodiments, the gap blocks 40 may be manufactured by injection molding or roll forming, as some examples. During installation, the installer may cut each gap blocker 40 to a length that substantially fills the entire lateral width of the associated gap 34. In this regard, the predetermined length of the gap blocker 40 may be substantially the same as the length of the roller 14. In another embodiment, multiple gap blocks 40 of smaller length may be installed into the gap 34 to fill the gap.

[0033] One or more of the leg portions 48, 50 of the elongated gap blocker 40 are resilient to allow them to elastically deform, thereby mounting the gap blocker 40 in the gap 34. The rollers 14 include elongated rollers 30, 32 having cylindrical outer surfaces 60, 62 that contact articles as they rotate to convey articles in the downstream direction 20. The gap blocker 40 includes an upper surface 52 that is recessed a distance 54 from a top surface portion 56 of the rollers 30, 32. As shown, the distance 54 is the vertical distance measured from a horizontal tangent line 5556 at the top of the rollers 30 down to the recessed upper surface 52 of the gap blocker 40. The recessed upper surface 52 allows articles to travel across the gap 34 via contact with the surfaces 60, 62 of the rollers 30, 32 without contacting the upper surface 52 of the gap blocker 40. Additionally, if the article portion extends far enough into gap 34 to occupy distance 54, gap blocker 40 contacts a portion of the conveyed article, thereby blocking or preventing the article portion from extending further into gap 34 and blocking or preventing the article portion from potentially becoming lodged between rollers 30, 32. In some embodiments, gap blocker 40 may be configured to sit higher in gap 34 such that gap blocker 40 is operable to assist in transferring articles between rollers 30, 32.

[0034] about Figure 2 , the upper barrier portion 44 of the body 42 includes an upstream outer portion 66 and a downstream outer roller engaging portion 68, which contact the roller surfaces 60, 62 at their upper half above the horizontal diameter lines 70, 92 of the rollers 30, 32. The upper barrier portion 44 has a central portion 45 extending between the junction of the upper barrier portion 44 and the leg portions 48, 50. The upstream outer portion 66 extends generally continuously from the junction of the upper barrier portion 44 and the leg portions 48, and the downstream outer roller engaging portion 68 is located at the junction of the upper barrier portion 44 and the leg portions 50. The upstream outer portion 66 and the downstream outer roller engaging portion 68 can form line contacts with the roller surfaces 60, 62. Each line contact is a localized area of ​​engagement between the contact surface and the roller that extends linearly in the transverse direction along the length of the roller. The leg portions 48 , 50 may be sized such that they do not extend below the plane of the bottom of the connecting rollers 30 , 32 so that they may not interfere with the belt at the bottom of the drive rollers 30 , 32 .

[0035] Upstream outer portion 66 contacts roller surface 60 at a surface portion 72 that forms an acute angle 74 with a diameter line 70 of upstream roller 30. Upstream leg portion 48 has a free end portion that includes a contact portion 80 that contacts a surface portion 82 of roller surface 60 below diameter line 70 of roller 30 at an acute angle 84. In one embodiment, angle 74 is in the range of 30-60 degrees and angle 84 is in the range of 20-50 degrees. Angle 74 may be greater than angle 84.

[0036] about Figure 2 , the downstream outer roller engaging portion 68 contacts an arcuate surface portion 90 of the cylindrical roller surface 62 above a diameter line 92 of the downstream roller 32 and forms a line contact with the cylindrical roller surface 62 of the downstream roller 32. The downstream leg portion 50 includes a free end portion that includes a contact portion 94 that contacts a surface portion 96 of the roller surface 62 below the equator 92. The contact portions 80, 94 of the upstream leg portion 48 and the downstream leg portion 50 may form a line contact with the roller surfaces 60, 62.

[0037] The roller surfaces 60, 62 can be made of a metallic material, such as stainless steel, and the body 42 of the gap stopper 40 can be made of a polymer, such as ultra-high molecular weight (UHMW) polyethylene or another plastic having a low coefficient of friction with the roller surfaces 60, 62. Furthermore, the gap stopper is configured to slidingly engage the roller surfaces 60, 62 through line contact, which minimizes the contact area between the gap stopper 40 and the rollers 30, 32. In this manner, the gap stopper 40 prevents items from becoming lodged in the gap 34 and prevents items or debris from falling through the gap 34, while minimizing the resistance of the gap stopper 40 to the rotation of the roller 14.

[0038] Reference Figure 2 and Figure 3 , gap blocker 40 has an initial configuration in which the contact portions 80, 94 of the upstream and downstream leg portions 48, 50 are spaced apart by a maximum distance 100. The contact portions 80, 94 include protruding corner portions 81, 95 formed by oppositely extending foot portions 152, 154 of the leg portions 48, 50. A maximum distance 100 is measured between the protruding corner portions 81, 95. The protruding corner portions 81, 95 have convex surfaces 81A, 95A that contact the convex outer surfaces of the rollers 30, 32. Convex surfaces 81A, 95A are where the leg portions 48, 50 contact the rollers 30, 32. Convex surface 81A provides an engaging, sliding contact with the roller 30, while convex surface 95A provides a clearance fit, such as a tight, rotational fit, with the roller 32. The remainder of the leg portions 48, 50 is spaced apart from the rollers 30, 32 to reduce frictional resistance to the rotation of the rollers 30, 32.

[0039] The distance 100 is greater than the distance between the surface portions 82, 96 of the rollers 30, 32 so that when the gap blocker 40 is installed in the gap 34, the leg portions 48, 50 are resiliently biased into contact with the roller surfaces 60, 62 to retain the gap blocker 40 in the gap 34. In one embodiment, the downstream leg portion 50 has a thickness 106 that is greater than a thickness 108 of the upstream leg portion 48 over at least a majority of its length. This configuration allows the upstream leg portion 48 to be more easily deflected to be pushed toward the downstream leg portion 50 and reduce the distance between the leg portions 48, 50 to fit the leg portions 48, 50 into the gap 34, as described below with respect to Figure 5 As discussed herein. The thinner upstream leg portion 48 can also flex to compensate for slight movement of the upper barrier portion 44 and maintain engagement of the upstream outer portion 66 with the upstream roller 30. In one embodiment, the upper barrier portion 44 has a thickness 107 that is substantially similar to the thickness 106 of the downstream leg portion 50, for example, within + / - 5% of the thickness 106 of the downstream leg portion 50. The respective thicknesses 106, 107 of the upper barrier portion 44 and the downstream leg portion 50 provide rigidity to the downstream leg portion 50 to resist frictional forces imparted on the gap barrier 40, as discussed herein.

[0040] The leg portions 48, 50 are arranged in a direction 110 (see Figure 2 ) advances far enough into gap 34 so that upstream outer portion 66 and downstream outer roller engaging portion 68 engage the rollers. Once the protruding corner portions 81, 95 of leg portions 48, 50 advance below the equator of rollers 30, 32, upstream leg portion 48 is resiliently biased away from downstream leg portion 50 and tightly biased against roller surface 60. In this manner, upstream leg portion 48 is tightly engaged with upstream roller 30. The biased engagement between contact portion 80 of upstream leg portion 48 and upstream roller 30 forms an anchor point 114 for gap stopper 40, which is circumferentially fixed at a location on the lower half of roller 30 when surface 60 rotates below its equator or horizontal diametrical line 70. Anchor point 114 is positioned a predetermined distance below diametrical line 70, which in turn maintains engagement of upstream outer portion 66 with roller surface 60. This limits lifting of upstream outer portion 66 away from roller surface 60 and associated vibration of gap stopper 40. Upstream leg portion 48 is configured to have an interference or radial overlap 112 with roller outer surface 60 such that when gap barrier 40 is in gap 34, upstream leg portion 48 is deflected by roller outer surface 60. Radial overlap 112 resiliently deflects leg portion 48 and provides a preload to leg portion 48 such that leg portion 48 resiliently maintains upstream outer portion 66 in tight engagement with roller surface 60.

[0041] The downstream leg portion 50 is thicker than the upstream leg portion 48 and is rigidly resistant to deflection such that the downstream leg portion 50 may not deflect when the gap blocker 40 is installed in the gap 34 and despite the upstream leg portion 48 being deflected. The downstream leg portion 50 is configured not to deflect when the gap blocker 40 is installed in the gap 34 and during normal operation of the conveyor system 10, but there may be occasional or regular de minimis deflection due to the forces applied to the downstream leg portion 50 by the rotating rollers 32. Additionally, the downstream leg portion 50 may deflect when an article being conveyed contacts the gap blocker 40. Figure 2 and Figure 3 , the downstream leg portion 50 has the same orientation relative to the upper blocking portion 44 when the gap blocker 40 is within the gap 34 and when the gap blocker 40 is outside the gap 34. The upstream leg portion 48 has a different orientation relative to the upper blocking portion 44 when the gap blocker 40 is within the gap 34 than when the gap blocker 40 is outside the gap 34. More specifically, when the gap blocker 40 is inside the gap 34, the upstream leg portion 48 deflects due to the interference between the upstream leg portion 48 and the roller outer surface 60.

[0042] about Figure 2 , during conveyor operation, the contact between the upstream outer portion 66 and the roller surface 60 generally pushes the upstream outer portion 66 in the downstream direction 20 and presses the downstream outer roller engaging portion 68 against the roller surface 62. The sliding contact between the downstream outer roller engaging portion 68 and the roller surface 62 tends to lift the downstream outer roller engaging portion 68, which presses the contact portion 94 of the downstream leg portion 50 against the roller surface 62. Due to its thicker construction, the downstream leg portion 50 is strong enough to resist the deflection toward the upstream leg portion 48 caused by the force of the camming action generated by this lifting movement of the downstream outer roller engaging portion 68 in the vertical direction 120 and maintain the downstream outer roller engaging portion 68 and the contact portion 94 engaged with the roller surface 62. In addition, the contact portion 94 of the downstream leg portion 50 forms an anchor point 122 for the gap barrier 40 below the equator 92 of the roller 32. With regard to Figure 2 and Figure 3 , the upstream leg portion 48 and the downstream leg portion 50 have upstream and downstream surfaces 180, 182, respectively, that face and are spaced apart from the respective roller surfaces 60, 62. Surfaces 180 and 182 may extend for a majority of the length of the leg portions 48 and 50, respectively, to reduce friction between the gap barrier 40 and the roller surfaces 60, 62 and to allow the gap barrier 40 to remain in place between the rollers 30, 32.

[0043] The roller conveyor 12 has rollers 30 connected to the track 24 (see Figure 1 ) of roller bearing 130. About Figure 2 The conveyor system 10 may also include skirt walls 132 that extend along opposing lateral sides of the rollers 14 to retain articles on the rollers 14 .

[0044] about Figure 3 , upstream outer portion 66 includes an edge 136 that can be more pointed than the more rounded edge 140 of downstream outer roller engaging portion 68. Edge 136 can provide a low-profile transition from roller surface 60 to limit the risk of edge 136 becoming trapped on an article being transferred from roller 30 to roller 32. Upstream outer portion 66 also includes a lower tapered surface 142 that can be a flat surface extending obliquely relative to upper surface 52, or concave to more closely conform to the curvature of roller surface 60. Upstream outer portion 66 protrudes outwardly from a transition portion 146 between upstream outer portion 66 and leg portion 48. Transition portion 146 connects upstream leg portion 48 to barrier portion 44.

[0045] Reference Figure 3 During installation of the gap blocker 40, the upstream leg portion 48 may be urged toward the downstream leg portion 50 in a direction 150 to reduce the distance 100 between the contact portions 80, 94 of the upstream and downstream leg portions 48, 50, thereby allowing the leg portions 48, 50 to advance into the gap 34. The upstream leg portion 48 and the downstream leg portion 50 may include oppositely extending foot portions 152, 154 that extend generally back toward each other and the central axis 160 of the gap blocker 40. The foot portions 152, 154 include inclined surfaces 156, 158 that extend transversely to the central axis 160 of the gap blocker 40. As the leg portions 48, 50 are advanced into the gap 120, one or more of the inclined surfaces 156, 158 may cammingly engage the roller surfaces 60, 62 of the rollers 30, 32 to urge the leg portions 48, 50 together.

[0046] Reference Figure 4 , the upper surface 52 of the gap blocker 44 includes a flat surface portion 162 and tapered surface portions 164, 166. The gap blocker 40 includes opposing lateral end portions 170, 172 having lateral sides 174, 176. The lateral sides 174, 176 may be flat or have other contours. As shown, the gap blocker 40 may be sized to extend along adjacent rollers 30, 32 for most or substantially the entire length of the gap 34, such that only a single gap blocker 40 is located in the gap 34. It is also contemplated that there may be two or more gap blocks 40 positioned side by side in the gap 34 to fill the lateral length of the gap 34.

[0047] Reference Figure 4 and Figure 5 A gap 184 exists between the upstream and downstream leg portions 48 , 50 , which may be narrowed during installation of the gap blocker 40 in the gap 34 by pushing the upstream leg portion 48 toward the downstream leg portion 50 .

[0048] To install the gap blocker 40 into the gap 34, first tilt the gap blocker 40 (see Figure 5 ), so that the central axis 160 of the gap blocking member 40 (see Figure 3 ) extends obliquely relative to an axis perpendicular to the downstream longitudinal direction 20. The gap barrier 40 is inclined so that the thicker downstream leg portion 50 is closer to the gap 34 than the thinner upstream leg portion 48.

[0049] The gap blocker 40 is then advanced in direction 110 so that the downstream leg portion 50 advances into the gap 34 and seats the downstream outer roller engaging portion 68 against the outer surface 62 of the roller 32, as shown. Figure 5 Additionally, the foot portion 152 of the upstream leg portion 48 may rest on the outer surface 60 of the roller 30. The direction 110 is generally orthogonal to the downstream conveying direction 20, such that for the horizontal conveying direction shown, the direction 110 is generally vertical.

[0050] Next, the installer pivots the upstream leg portion 48 generally in direction 190 toward the downstream leg portion 50 to reduce the size of the gap 184 between the upstream and downstream leg portions 48, 50. The installer then rocks the gap blocker 40 in direction 192 while maintaining the upstream leg portion 48 in its deflected position adjacent the downstream leg portion 50, causing the inclined surface 156 of the foot portion 152 to slide along the roller surface 60 and the foot portion 152 to advance further into the gap 34 in direction 110. The installer presses on the blocking portion 44 to push the gap blocker 40 further downward into the gap 34 until the contact portion 156 of the upstream leg portion 156 snaps below the horizontal diameter 70 of the roller 30. In some embodiments, the downstream leg portion 50 is sufficiently rigid that the downstream leg portion 50 resists deflection and remains in position as the upstream leg 48 deflects in direction 190 and the upstream and downstream leg portions 48, 50 advance in direction 110 into the gap 34. Figure 5 The orientation relative to the upper barrier portion 44 is shown in .

[0051] Due to the lateral length of gap barrier 40, the installer may first position one lateral side portion 170, 172 in gap 34 as described above by pushing upstream leg portion 48 toward downstream leg portion 50. The installer may then position the other lateral side portion 170, 172 into gap 34 by keeping upstream leg portion 48 pushed toward downstream leg portion 50 and pressing the other lateral side portion 170, 172 into gap 34.

[0052] Reference Figure 6 , another gap barrier 200 is provided that is similar in many respects to the gap barrier 40 discussed above, so that only the differences will be emphasized. The gap barrier 200 includes a unitary body 202 having an upper barrier portion 204 and a lower leg portion 206. The leg portion 206 includes a downstream leg portion 208 and a pair of upstream leg portions 210, 212. The gap barrier 200 can have two, three, four, or any number of spaced-apart upstream leg portions, as desired for a particular application. The upstream leg portions 210, 212 have side surfaces 214, 216 that are laterally separated by an opening 218. The opening 218 provides a reduced contact surface area against the upstream roller at the lower upstream portion of the gap barrier 200. More specifically, the gap barrier 200 has a pair of relatively small contact portions 220, 222 of the upstream leg portions 210, 212 that engage the upstream roller. The contact portions 220, 222 have convex surfaces that form line contact with the convex outer surface of the upstream roller. This can reduce the frictional contact between the gap barrier 20 and the upstream roller.

[0053] about Figure 7 , another gap blocker 300 is provided which is similar in many respects to the gap blockers discussed above so that only the differences will be emphasized. The gap blocker 300 includes an upper blocking portion 302, leg portions 304, 306, and upstream and downstream outer roller engaging portions 308, 310 of the body 301. The gap blocker 300 is symmetrical about a center axis 312. The symmetry of the gap blocker 300 allows the gap blocker 300 to be installed in a gap between rollers with either the leg portion 304 or the leg portion 306 positioned against the upstream roller. The leg portions 304, 306 are symmetrically configured and have similar thicknesses 314, 316 to provide similar resilience so that during installation of the gap blocker 300, either of the leg portions 304, 306 can be deflected in directions 320, 322 toward the other leg portion 304, 306. About Figure 8 , the roller engaging portions 308, 310 both have rounded edges 330 to form line contact with the associated roller.

[0054] The gap stopper 300 may have an upper stopper portion 302 with a thickness 340 that is substantially equal to the thicknesses 314, 316 of the leg portions 304, 306. As some examples, the thicknesses 314, 316, 340 may differ from each other by + / - 5%.

[0055] about Figure 9 , a gap blocker 400 is provided that is similar in many respects to the gap blocks discussed above, so that the differences will be emphasized. The gap blocker 400 has a body 402 that includes an upper blocking portion 404 for blocking a gap 406 and a lower portion 408 for retaining the gap blocker 400 in the gap 406. In one embodiment, the body 402 has a one-piece, one-piece structure. The body 402 can be made of a plastic material, such as injection molding, extrusion, or additive manufacturing, as some examples. The upper blocking portion 404 includes outer portions 410, 412 and a center portion 414. The outer portions 410, 412 each have a tapered upper surface 416, edges 418, 419, and tapered lower surfaces 420, 421 that taper toward each other to outer edges 418, 419. The tapered lower surface 420 of the outer portions 410, 412 can contact the cylindrical surfaces 422, 424 of the rollers 426, 428. In some embodiments, the edges 418, 419 make contact with the surfaces 422, 424.

[0056] Gap blocker 400 has a central axis 430 and is symmetrical about central axis 430. This allows gap blocker 400 to be positioned in gap 406 with either outer portion 410, 412 oriented to contact upstream roller 426 to receive gap 406 and block it from articles traveling in direction 440. Lower portion 408 of body 402 includes leg portions 450, 452 having contact portions 454, 456 that contact roller surfaces 422, 424 below diametrical lines 460, 462 of rollers 426, 428. Leg portions 450, 452 each have an outer surface 490, 492 that is spaced from surfaces 422, 424 of rollers 426, 428 by gaps 494, 496 to limit contact between gap blocker 400 and rollers 426, 428. Once the gap blocker 400 is installed between the rollers and during operation of the roller conveyor thereafter, this gap exists between the surfaces 490, 492 and the adjacent rollers 426, 428. Thus, as the rollers 426, 428 rotate, along their entire lengths, the surfaces 490, 492 of the gap blocker 400 remain spaced from the adjacent rollers 426, 428 without any frictional engagement therebetween.

[0057] The gap stopper 400 is supported in the gap 406 by the outer portions 410, 412 in sliding contact with the roller surfaces 422, 424 and the weight of the gap stopper 400 maintaining the outer portions 410, 412 in contact with the roller surfaces 422, 424. The contact portions 454, 456 of the leg portions 450, 452 are generally in clearance with the roller surfaces 422, 424, such as having a close rotational fit with the roller surfaces 422, 424. The contact portions 454, 456 of the leg portions 450, 452 may occasionally contact the roller surfaces 422, 424 to resist or minimize chattering of the gap stopper 400. The contact portions 454, 456 of the leg portions 450, 452 are typically in clearance from the roller surfaces 422, 424 during operation of the rollers 426, 428, which limits the surface area of ​​the gap blocker 400 that can resist the rotation of the rollers 426, 428 and reduces the frictional resistance of the gap blocker 400 to the rotation of the rollers 426, 428. Furthermore, when the gap blocker 400 is in the gap 406, the leg portions 450, 452 are in an undeflected configuration, thereby avoiding pinching the rollers 426, 428 between the outer portions 410, 412 and the leg portions 450, 452, further reducing the frictional resistance of the gap blocker 400 to the rotation of the rollers 426, 428. Thus, the gap blocker 400 can prevent conveyed articles from falling through the gap 406 while maintaining the operational efficiency of the roller conveyor.

[0058] Upper barrier portion 404 includes an upper surface 466 that is recessed relative to top surface portions 468, 470 of rollers 426, 428. This allows packages or other articles to be transferred from roller 426 to roller 428 in downstream direction 440 without contacting gap blocker 400. In other embodiments, gap blocker 400 is configured to position upper barrier portion 404 higher in gap 406 so that articles are transferred from roller 426 to roller 428 via upper surface 466.

[0059] The body 402 includes joints 474, 476 between the leg portions 450, 452 and the upper barrier portion 404. The leg portions 450, 452 include substantially straight portions 480, 482 depending from the joints 474, 476. The straight portions 480, 482 extend at an angle 484 relative to the outer portions 410, 412. The thickness of the straight portions 480, 482 in the longitudinal direction can decrease as the leg portions 480, 482 extend downward from the upper barrier portion 404, which distributes the curvature of the leg portions 480, 482 over the length of the straight portions 480, 482. In one embodiment, the angle 484 is substantially vertical, i.e., ninety degrees plus or minus five degrees. The orientation of the outboard portions 410 , 412 and straight portions 480 , 482 of the leg portions 450 , 452 creates a branching shape on the upstream and downstream sides of the body 402 as the body 402 extends away from the center portion 414 of the body 402 .

[0060] The leg portions 450, 452 extend downwardly away from the upper barrier portion 404 and include lower curved portions 500, 502 that curve below the horizontal diametrical lines 460, 462 of the rollers 426, 428. The curved portions 500, 502 position the end portions 504, 506 of the leg portions 450, 452 below the diametrical lines 460, 462.

[0061] The end portions 504, 506 include contact portions 454, 456. In one embodiment, the contact portions 454, 456 include convex surface portions 510, 512, each having a radius of curvature 514, 516, which may be similar or different. The end portions 504, 506 also include inclined surface portions 520, 522 that can cam against the roller surfaces 422, 424 as the leg portions 450, 452 advance downwardly into the gap 406, such that engagement therebetween pushes the leg portions 450, 452 toward each other, allowing the contact portions 454, 456 to advance past the narrowest portion of the gap 406 defined between the diametrical lines 460, 462 of the rollers 426, 428. The end portions 504 , 506 may include foot portions 524 , 526 having portions of the convex surface portion 512 and / or the inclined surface portion 522 thereon.

[0062] about Figure 10, a gap blocker 600 is provided that is similar in many respects to the gap blocks discussed above. Gap blocker 600 includes a body 602 having an upper blocking portion 604 and a lower portion 606 including leg portions 608, 610. Body 602 has an upstream outer portion 612 and a downstream outer roller engaging portion 614. Gap blocker 600 includes an extended convex surface 620 of the downstream outer roller engaging portion 614 and extended convex surfaces 622, 624 of the contact portions 626, 628 of the leg portions 608, 610. Upstream outer portion 612 has an edge 630 that contacts an upstream roller 632 and blocks a gap 632 between upstream roller 632 and downstream roller 634. Upper barrier portion 604 has an upper surface 636 that is partially concave relative to upper surfaces of rollers 632 , 634 so that articles can be conveyed from rollers 632 , 634 in direction 640 without contacting gap barrier 600 .

[0063] about Figure 11 , a gap blocker 700 is provided that is similar in many respects to the gap blocks discussed above. Gap blocker 700 has a body 702 that includes an upper blocker portion 704 and a lower portion 706 having leg portions 708, 710. Body 702 has a central axis 712 and is symmetrical about axis 712. Upper blocker portion 704 includes similar outer roller engaging portions 720, 722 and includes convex surfaces 724, 726 for contacting rollers 728, 730. Leg portions 708, 710 also have convex surface portions 732, 734 that form line contact with surfaces 736, 738 of rollers 728, 730. Except at convex surface portions 732, 734, leg portions 708, 710 are spaced apart from roller surfaces 736, 738.

[0064] about Figure 12 , a system 800 is provided that includes rollers 802, 804 with a gap 905 therebetween, a gap blocker 806 similar to the gap blocker 400 discussed above, and a drive member such as an O-ring 808. The O-ring 808 can be a single, integral member or can include multiple members, such as cables. In some embodiments, the O-ring 808 is made of a polymer material. The drive member can take other forms, such as a chain.

[0065] Rollers 802, 804 each have a cylindrical outer surface 810 having an outer diameter 812 that supports gap stop 806 and a groove portion 814. Groove portion 814 includes a groove 816 formed in cylindrical outer surface 810, groove 816 having a minimum outer diameter 818.

[0066] The O-ring 808 surrounds the rollers 802, 804 such that the O-ring 808 has an upper portion 826 and a lower portion 828 that extend across the gap 805. The O-ring 808 has a semicircular portion that extends in the groove 816 on each side of the rollers 802, 804 opposite the gap blocker 806. The semicircular portion of the O-ring 808 connects the upper portion 826 and the lower portion 828. The rollers 802, 804 and the upper portion 826 and lower portion 828 of the O-ring 808 form an opening 830 in the gap 905. The O-ring 808 engages the rollers 802, 804 by extending into the groove 816 of the rollers 802, 804 and engaging the surface 820 of the groove 816.

[0067] In one embodiment, roller 802 is rotated in direction 822 by an O-ring connected to an upstream roller, causing roller 802 to rotate in direction 822 to convey articles in a downstream direction 824. O-ring 808 can be made of an elastic material and is placed under tension as it extends around rollers 802, 804. The tension in O-ring 808 causes O-ring 808 to tightly engage surface 820 of groove 816. The rotation of roller 802 in direction 822 pushes lower portion 828 of O-ring 808 in direction 832, causing O-ring 808 to rotate roller 804 in direction 834. The rotation of roller 802 in direction 822 also pulls upper portion 826 of O-ring 808 away from roller 802 and directs it toward roller 804.

[0068] The gap stopper 806 has an upper surface 840, a lower surface 842, and a height 844. The height 844 of the gap stopper 806 is less than the outer diameter 812 of the roller outer surface 810 and the minimum outer diameter 818 of the groove 816 of the rollers 802, 804. The height 844 of the gap stopper 806 is also less than the distance 850 between the lower surface portion 852 of the upper portion 826 of the O-ring 808 and the upper surface portion 854 of the lower portion 828 of the O-ring 808. In this manner, the gap stopper 806 can extend laterally along the cylindrical outer surface 810 of the rollers 802, 804 (into or out of the rollers 802, 804). Figure 12 805) to prevent items from falling through gap 805, while also preventing items from extending into opening 830 formed by O-ring 808 and rollers 802 and 804 having a gap with O-ring 808. Because gap stopper 806 has a gap with O-ring 808, O-ring 808 can transmit the rotation of roller 802 to roller 804 without being interfered with by gap stopper 806.

[0069] In some applications, gap blocker 806 is initially installed in gap 805 with a portion of gap blocker 806 extending in opening 830 formed by O-ring 808 and rollers 802, 804. In other applications, gap blocker 806 is installed in gap 805 laterally offset from groove 816 and O-ring 808. Over time, gap blocker 806 can shift laterally into opening 830 formed by O-ring 808 and rollers 802, 804 without interfering with the movement of O-ring 808.

[0070] refer to Figure 13 , shows gap blocker 900 inserted into gap 902 between rollers 904, 906. Gap blocker 900 is similar to the gap blocks discussed above and includes a body 910 having an upper blocking portion 912 and leg portions 914, 916. To position gap blocker 900 in gap 902, outer portions 918 of upper blocking portion 912 and leg portions 916 are positioned against the cylindrical outer surface of roller 906, and leg portion 914 is deflected in direction 920 toward leg portion 916. With leg portion 914 deflected, gap blocker 900 can be rocked or pushed in direction 922 to position contact portions 924, 926 of leg portions 914, 916 below the narrowest portion of gap 902.

[0071] Reference Figure 14 Each leg portion 914, 916 of gap stopper 900 includes a straight portion 930 extending downward from upper stopper portion 912 and a curved portion 932 below straight portion 930. Curved portion 932 has a rough or faceted configuration, including straight segments 934, 936 extending transversely to straight portion 930 and transversely to each other. The faceted configuration of leg portions 914, 916 can make the body 910 of gap stopper 900 easier to injection mold. Specifically, gap stopper 900 can be manufactured from molded plastic, and the faceted configuration of leg portions 914, 916 allows a metal mold portion to be pulled out of the plastic without scratching or catching the plastic when the metal mold portion is retracted.

[0072] Like the other gap stops discussed herein, gap stopper 900 can be removed from gap 902 by lifting upward on upper stopper portion 912. The cylindrical outer surfaces of rollers 904, 906 displace leg portions 914, 916 together relative to upper stopper portion 912, temporarily reducing the maximum width across leg portions 914, 916. Gap stopper 900 continues to be lifted upward until contact portions 924, 926 pass over the narrowest portion of gap 902. Once leg portions 914, 916 have been withdrawn from gap 902, leg portions 914, 916 resiliently displace back away from each other relative to upper stopper portion 912.

[0073] Unless otherwise indicated herein or clearly contradicted by context, use of singular terms such as "a," "an," and "the" are intended to encompass both the singular and the plural. The terms "comprising," "having," "including," and "containing" are to be construed as open-ended terms. As used herein, the phrase "at least one of" is intended to be interpreted disjunctively. For example, the phrase "at least one of A and B" is intended to encompass A, B, or both A and B.

[0074] While particular embodiments of the invention have been illustrated and described, it will be appreciated that numerous changes and modifications will occur to those skilled in the art, and the invention is intended to cover all such changes and modifications that fall within the scope of the appended claims.

Claims

1. A gap barrier for a roller conveyor, the roller conveyor comprising rollers for conveying articles in a downstream longitudinal direction and gaps between the rollers, the gap barrier comprising: a body to be positioned in the gap between the rollers; an upper blocking portion of the main body for preventing articles carried by the roller from falling through the gap; leg portions of the body, the leg portions connected to the upper barrier portion at longitudinally spaced locations such that the leg portions have a space therebetween extending in the longitudinal direction; the leg portions having an initial undeflected configuration, wherein at least one of the leg portions has a first orientation relative to the upper barrier portion; The leg portions of the body are offset relative to each other to reduce the distance across the space between the leg portions to facilitate advancing the body into the gap; the leg portions of the body having an operational configuration, wherein the body is in the gap, at least one of the leg portions having the first orientation relative to the upper barrier portion when the leg portions are in the operational configuration; an upper contact portion of the upper blocking portion and a lower contact portion of the leg portion for contacting the roller and supporting the body in the gap; as well as An outer surface portion of the body is configured to be in clearance with the roller when the body is in the gap and the leg portion is in the operating configuration, the outer surface portion of the body being intermediate the upper contact portion and the lower contact portion along the roller.

2. The gap blocking member according to claim 1, wherein: The at least one leg portion includes an upstream leg portion and a downstream leg portion, each having its first orientation relative to the upper blocking portion when the leg portions are in the initial undeflected configuration and the operational configuration.

3. The gap blocking member according to claim 1, wherein: The leg portion includes a first leg portion having a second orientation relative to the upper blocking portion when the leg portion is in the initial undeflected configuration and a different third orientation relative to the upper blocking portion when the leg portion is in the operational configuration.

4. The gap blocking member according to claim 1, wherein: The leg portion includes a resilient leg portion configured to deflect when the body is in the gap and the leg portion is in the operative configuration.

5. The gap blocking member according to claim 1, wherein: The upper barrier portion has a flat lower surface, and the leg portion includes a straight portion depending from the flat lower surface of the upper barrier portion.

6. The gap blocking member according to claim 5, characterized in that: The straight portion is substantially perpendicular to the flat lower surface of the upper blocking portion.

7. The gap blocking member according to claim 1, wherein: The outer surface portion of the body is an outer surface portion of the leg portion that faces the roller when the body is positioned in the gap.

8. The gap blocking member according to claim 1, wherein: said leg portion including said outer surface portion; wherein the lower contact portion of the leg portion includes a protrusion; and wherein the outer surface portion extends from the protrusion toward the upper blocking portion.

9. The gap blocking member according to claim 1, wherein: The lower contact portion of the leg portion includes a convex surface to contact the roller.

10. The gap blocking member according to claim 9, characterized in that: The leg portion includes the outer surface portion of the body, the outer surface portion including a concave surface portion.

11. The gap blocking member according to claim 1, wherein: the upper barrier portion including an upper barrier surface extending longitudinally between the rollers; wherein the body includes a middle portion below the upper blocking portion, the upper blocking portion being configured to fit into the gap between the rollers at a narrowest portion of the gap in the longitudinal direction; The main body has a dimension in the longitudinal direction that continuously decreases as the main body extends from the upper contact portion to the middle portion.

12. The gap blocking member according to claim 11, wherein: said leg portion including said middle portion of said body; wherein the lower contact portion of the leg portion includes a protrusion; and The leg portion has a dimension across the leg portion in the longitudinal direction that continuously increases as the leg portion extends downwardly away from the middle portion.

13. The gap blocking member according to claim 1, wherein The lower contact portion of the leg portion is configured to form a transverse line contact with the roller.

14. The gap blocking member according to claim 1, wherein The body has opposite lateral sides, a length extending transversely between the lateral sides, and a cross-section perpendicular to the length, the cross-section being consistent from one lateral side to the other.

15. The gap blocking member according to claim 1, wherein The body is plastic.

16. The gap blocking member according to claim 1, wherein The body has an integral one-piece structure.

17. The gap blocking member according to claim 1, wherein The leg portions are longitudinally aligned.

18. The gap blocking member according to claim 1, wherein The leg portions include a pair of upstream leg portions, and the at least one leg portion includes a downstream leg portion.

19. The gap blocking member according to claim 1, wherein The leg portions each include a base portion connected to the upper barrier portion and a free end portion opposite the base portion.

20. The gap blocking member according to claim 1, wherein The body has an upstream surface facing an upstream roller of the roller and a downstream surface facing a downstream roller of the roller; wherein the upstream surface and the downstream surface extend from the upper contact portion of the upper blocking portion to the lower contact portion of the leg portion, respectively; wherein said upstream surface and said downstream surface of said body include said exterior surface portions; as well as wherein the upstream surface and the downstream surface of the body are in clearance from the roller when the body is in the gap and the leg portion is in the operative configuration.

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