Variable pitch chain assembly

Claim 2

A link chain assembly for use under tension in moving a load along a path including a slow travel zone and a fast travel zone arranged in end-to-end relation and which chain assembly has the capability of changing the effective length of portions thereof automatically and progressively while moving continuously under tension past the adjacent ends of said slow and fast zones, said chain assembly comprising a multiplicity of links movably connected together, pairs of lever arms means connected one to each of adjacent links of said chain assembly for pivotal movement about a common pivot axis, and each of said lever arm means having an outer free end equipped with cam follower means adapted to engage cam means for pivoting said lever arm means and the link secured thereto in opposite directions about said common pivot axis to change the effective pitch of the adjacent portion of said chain and thereby the rate of travel of the portion experiencing the changes in length.

Claim 3

A link chain assembly as defined in claim 1 characterized in that said lever arm means is connected to the associated link closely adjacent one end thereof.

Claim 4

A link chain assembly as defined in claim 2 characterized in that said lever arm means are arranged to pivot through arcs not in excEss of 90* between a collapsed position closely spaced from and substantially parallel to the longitudinal centerline of the path of travel of said chain and an extended position of said lever arm means generally normal to said path of travel.

Claim 5

A link chain assembly as defined in claim 1 characterized in that each lever arm means of a pair thereof is arranged to pivot substantially in unison and in opposite directions toward and away from a respective side of the path of travel of said chain assembly.

Claim 6

A link chain assembly as defined in claim 1 characterized in that the lever arm means of each pair thereof project away from the opposite lateral sides of said chain links.

Claim 7

A link chain assembly as defined in claim 1 characterized in that said lever arm means are fixed to one end of the associated one of said links and constitute an extension thereof effective to pivot the link about said common pivot axis located closely adjacent the junction of the lever arm means and said link.

Claim 8

A link chain assembly as defined in claim 1 characterized in that the cam follower means on adjacent ones of said lever arm means are located on the opposite sides of said links and move in arcuate paths toward and away from said links as the effective pitch of said link chain assembly changes.

Claim 9

A link chain assembly as defined in claim 7 characterized in that said cam follower means comprise roller means journaled to the outer free ends of said lever arm means and which roller means are adapted to roll against camming means spaced varying distances from the path of travel of alternate ones of the movable connections between said elongated links.

Claim 10

A link chain assembly as defined in claim 1 characterized in that said links are pivotally connected together by pivot pin means, the axes of alternate ones of which are coincident with the common pivot axes of said pairs of lever arm means.

Claim 11

A link chain assembly as defined in claim 1 characterized in that said links each include a first pair of strips arranged in spaced apart parallel relation and interconnected by pair of pivot pin and roller assemblies, a respective one of said pair of pivot pin and roller assemblies serving to connect said first pair of strips pivotally to an adjacent pair of said strips.

Claim 12

A link chain assembly as defined in claim 9 characterized in that one end of said pivot pin means coincident with the common pivot axes of said pairs of lever arm means projects axially beyond one lateral side of said chain assembly and is adapted to be operatively connected to load-supporting means movable with said chain assembly.

Claim 13

A link chain assembly as defined in claim 1 characterized in that the length of said lever arm means extends generally at right angles to the length of the associated link.

Claim 14

A link chain assembly as defined in claim 12 characterized in that the main bodies of said lever arm means are positioned to internest as the same pivot toward one another while passing along said slow travel zone.

Claim 15

A link chain assembly as defined in claim 1 characterized in that said cam means converge in passing between one adjacent set of merging ends between fast and slow zones of travel and diverge in passing between the next adjacent set of merging ends between fast and slow zones of travel.

Claim 16

A link chain assembly as defined in claim 11 characterized in that said pivot pin means having axes in common with the associated pair of lever arm means remain in general alignment with the draft forces acting lengthwise of said chain assembly as it advances along its path of travel through said slow and fast zones, and intervening ones of said pivot pin means moving laterally toward and away from a line passing through said first-mentioned pivot pin means.

Claim 17

A link chain assembly as defined in claim 15 characterized in that said lever arm means are fixed to said links closely adjacent and immediately in advance of the associated ones of said pivot pin means and are positIoned to nest together closely against the opposite sides thereof while passing through said slow travel zone.

Claim 18

A link chain assembly as defined in claim 16 characterized in that said lever arm means are positioned to pivot rearwardly toward the opposite sides of trailing portions of said chain assembly while passing from a fast travel zone into a slow travel zone.

Claim 19

A link chain assembly as defined in claim 17 characterized in that said lever arm means include a pair of lever arms fixed to a respective one of said links and diverging from one another.

Claim 20

A link chain assembly as defined in claim 18 characterized in that the outer free ends of each of said lever arms are provided with cam follower roller means each adapted to contact camming means cooperating therewith to control the pitch of the particular links of said chain assembly to which said lever arms are fixed.

Claim 21

A link chain assembly as defined in claim 16 characterized in that adjacent ones of said lever arm means are fixed to respective links closely adjacent the ends thereof movably connected together, and said adjacent ones of said lever arm means acting to pivot said respective links in opposite directions about the movable connection between their adjacent ends as said chain assembly passes through said slow travel zone.

Claim 22

A link chain assembly as defined in claim 18 characterized in that the ends of said pairs of adjacent lever arm means overlap and internest as said pairs of lever arm means pivot toward one another and approach the opposite sides of trailing portions of said chain assembly.

Claim 23

A link chain assembly as defined in claim 21 characterized in that the ends of said pairs of adjacent lever arm means move out of overlapping internesting positions as their outer free ends pivot away from one another and as the associated links of said chain speed up while leaving a slow rate travel zone.

Claim 24

A link chain assembly as defined in claim 1 characterized in the provision of rolling support means along the lower side of said chain assembly.

Claim 25

A link chain assembly as defined in claim 1 characterized in the provision of pivot pin means coupling adjacent ends of said links together to form a chain assembly freely flexible in a first plane extending crosswise of said links and which is relatively nonflexible in a second plane normal to said first plane and extending lengthwise of said links, and camming means extending along the opposite sides of said slow travel zones positioned to hold alternate ones of said pivot pin means aligned with the path along which the draft forces are applied to drive said chain assembly and the remaining alternate ones of said pivot pin means being movable along a compound curvate path while passing through said slow travel zone.

Claim 26

A link chain assembly as defined in claim 24 characterized in that the midportions of said camming means extending along said slow travel zone are generally parallel to one another and in that the portions of said camming means to either end of said midportions are inclined in opposite directions with respect to the path along which said draft forces are applied.

Claim 27

A link chain assembly as defined in claim 25 characterized in the provision of a multiplicity of individual load-supporting members cooperating to provide a generally level load-supporting surface closely overlying said chain assembly, and means providing a draft connection between individual ones of said load-carrying means and a respective one of said pivot pin means having axes common to said pivoting lever arm means.

Claim 28

A link chain assembly as defined in claim 25 characterized in that the inclined portions of said camming means at the opposite ends of said slow travel zone flare in a direction opposite the direction of flare at the other end.

Claim 29

A link chain assembly as defined in claim 27 characterized in that the portions of said camming means at the opposite ends of said slow travel zones flare in opposite directions and asymmetRically.

Claim 30

A link chain assembly as defined in claim 1 characterized in that said camming means at the opposite ends of said slow travel zones flare in opposite directions and asymmetrically.

Claim 31

A link chain assembly as defined in claim 1 characterized in that said camming means along either side of said chain assembly at said slow travel zones has different portions thereof spaced different distances from the line of the draft forces applied to said chain assembly and the camming means on one side of said chain assembly being asymmetrical with respect to the camming means on the other side thereof.

Claim 32

A conveyor system comprising a power propelled chain of links movably connected together for operation in continuous tension and having one portion of its length contracted with individual parts of links therealong arranged in short-pitch V-formation and another portion of its length stretched so that the links of said individual pairs are arranged in relatively long-pitch generally aligned relation lengthwise of the path of travel, and arm means rigidly attached to said pairs of links and projecting from the opposite sides of said chain and positioned to engage camming means positioned along either side of said chain and cooperating with said arm means to vary the angular positions of the links comprising each of said pair as said chain is advanced along its path of travel, whereby the links of said chain in stretched long-pitch condition travel at a rate which is substantially higher than the travel rate of the links contracted into short-pitch V-formation.

Claim 33

A conveyor system comprising a power propelled chain of links movably connected together for operation in continuous tension and having one portion of its length contracted with individual parts of links therealong arranged in short-pitch V-formation and another portion of its length stretched so that the links of said individual pairs are arranged in relatively long-pitch generally aligned relation lengthwise of the path of travel, and arm means rigidly attached to said pairs of links and projecting from the opposite sides of said chain and positioned to engage camming means positioned along either side of said chain and cooperating with said arm means to vary the angular positions of the links comprising each of said pair as said chain is advanced along its path of travel, whereby the links of said chain in stretched long-pitch condition travel at a rate which is substantially higher than the travel rate of the links contracted into short-pitch V-formation.

Claim 34

A conveyor system arranged along a path of travel and including a slow travel zone and a fast travel zone, said system comprising a power driven link chain assembly movably connected together and supported for movement through said slow and fast zones in sequence with all parts thereof operating under tension, camming means supported along the opposite sides of said chain with its camming surfaces spaced apart differently along different portions of the length of said chain, and lever arm means operatively associated with said links including cam follower means at the outer ends with successive ones thereof positioned to engage alternate ones of said camming means and cooperating therewith to move adjacent pairs of chain links into a relatively short-pitch, more compact arrangement to slow the rate of travel thereof while passing through said slow travel zone and into a substantially long-pitch, stretched arrangement to increase their rate of travel while passing through said fast travel zone, and work performing means operatively connected to and movable with said link chain assembly as the same is driven through said slow and fast travel zones.

Claim 35

A conveyor system arranged along a path of travel and including a slow travel zone and a fast travel zone, said system comprising a power driven link chain assembly movably connected together and supported for movement through said slow and fast zones in sequence with all parts thereof operating under tension, camming means supported along the opposite sides of said chain with its camming surfaces spaced apart differently along different portions of the length of said chain, and lever arm means operatively associated with said links including cam follower means at the outer ends with successive ones thereof positioned to engage alternate ones of said camming means and cooperating therewith to move adjacent pairs of chain links into a relatively short-pitch, more compact arrangement to slow the rate of travel thereof while passing through said slow travel zone and into a substantially long-pitch, stretched arrangement to increase their rate of travel while passing through said fast travel zone, and work performing means operatively connected to and movable with said link chain assembly as the same is driven through said slow and fast travel zones.

Claim 36

A conveyor system as defined in claim 32 characterized in that said link chain assembly comprises an endless loop, a plurality of rotary wheel means for holding said link chain assembly outstretched, and driving means for driving said conveyor system.

Claim 37

A conveyor system as defined in claim 33 characterized in that said driving means is operable normally at uniform speed.

Claim 38

A conveyor system as defined in claim 34 characterized in that said driving means is connected to said link chain assembly at a single drive station.

Claim 39

A conveyor system as defined in claim 32 characterized in that said system includes a pair of similar link chain assemblies cooperating to support said load-carrying means while advancing it from place to place along the path of travel.

Claim 40

A conveyor system as defined in claim 36 characterized in the provision of a multiplicity of rolling means for supporting each of said link chain assemblies.

Claim 41

A conveyor system as defined in claim 33 characterized in the provision of not less than two slow travel zones separated by at least one fast travel zone.

Claim 42

A conveyor system as defined in claim 38 characterized in the provision of a plurality of fast travel zones separated from one another by intervening slow travel zones.

Claim 43

A conveyor system as defined in claim 39 characterized by the provision of a single uniform-speed prime mover for said link chain assembly.

Claim 44

A link chain assembly as defined in claim 1 characterized in that the links thereof have equal pitch.

Claim 45

A link chain assembly as defined in claim 41 characterized in that the said assembly is contracted to a pitch wherein the adjacent edges of alternate links are substantially parallel to one another.

Claim 46

A linkage assembly for use in a variable pitch chain having separate portions thereof adapted to travel at different rates of speed, said linkage assembly comprising a plurality of links arranged with the adjacent ends thereof in overlapping movably connected relationship to form a flexible chain, and means secured to said links at the adjacent ends of successive pairs of links and projecting from the opposite sides thereof for use in causing adjacent ones of said links to pivot in opposite directions as said linkage assembly is propelled under tension from end to end thereof thereby causing said linkage assembly to change in pitch and in the rate of travel of said pivoting links relative to other links of said linkage assembly.

Claim 47

A linkage assembly for use in a variable pitch chain having separate portions thereof adapted to travel at different rates of speed, said linkage assembly comprising a plurality of links arranged with the adjacent ends thereof in overlapping movably connected relationship to form a flexible chain, and means secured to said links at the adjacent ends of successive pairs of links and projecting from the opposite sides thereof for use in causing adjacent ones of said links to pivot in opposite directions as said linkage assembly is propelled under tension from end to end thereof thereby causing said linkage assembly to change in pitch and in the rate of travel of said pivoting links relative to other links of said linkage assembly.

Claim 48

A linkage assembly as defined in claim 43 characterized in that said links are generally L-shaped and in that the junction areas of their respective pairs of legs are pivotally connected together with the legs of each extending generally in opposite directions when the assembly is stretched toward its maximum pitch, and pivot means interconnecting the overlapped ends of the legs of adjacent ones of said L-shaped links.

Claim 49

A linkage assembly as defined in claim 2 characterized in that the legs of said links projecting outwardly from the opposite sides of said linkage assembly lie in planes inclined acutely away from a common plane extending transversely of said linkage assembly and sufficiently to permit said legs to be moved into internesting relationship as said linkage assembly is shortened to slow the rate of travel of said shortened portion.