Reciprocating conveyor for particulate material

A reciprocating conveyor is formed of at least one group of at least three elongated slats of inverted U-shape spaced apart laterally for longitudinal reciprocation in such manner that all or a majority of slats move simultaneously in a load conveying direction and sequentially in the opposite, retracting direction. A seal member is secured to one side section of each slat and extends laterally therefrom to a position closely adjacent the facing side section of the adjacent slat. The fines of particulate material being conveyed as a load gravitate downward past the free side of the seal member and are deposited in a trough that underlies each pair of facing side sections of adjacent slats. As the adjacent slats move simultaneously in the load conveying direction, the corresponding pair of facing side sections move the fines in the trough in the same direction. This movement is enhanced by providing fines pusher members on the lower ends of the side sections of the slats.

BACKGROUND OF THE INVENTION 
This invention relates to reciprocating conveyors, and more particularly to 
a reciprocating conveyor especially suitable for the conveying of 
particulate materials. 
My earlier U.S. Pat. Nos. 3,534,875; 4,143,760; 4,144,963; and 4,184,587 
disclose reciprocating conveyors particularly suitable for the conveying 
of packaged goods, bulk farm crops and non-abrasive particulate materials. 
Although those conveyors are highly effective for those purposes, they are 
inefficient in conveying such abrasive particulate materials as sand, 
solid particles in sewage and others, because the seals between adjacent 
conveyor slats do not prevent the escape of such materials and also do not 
withstand the destructive abrasion of such materials. 
SUMMARY OF THE INVENTION 
The reciprocating conveyor of this invention utilizes a plurality of groups 
each of at least three elongated, longitudinally reciprocative, laterally 
spaced slats of inverted U-shaped cross section driven in such manner that 
all or a majority of the slats of each group move simultaneously in a load 
conveying direction and move sequentially in the opposite, retracting 
direction, the mutually facing side sections of adjacent slats registering 
with an underlying elongated fines removal trough. An elongated seal 
member is secured along one edge to one of the facing sides of each 
adjacent pair of slats with the opposite, free side of the seal member 
positioned closely adjacent the other facing side of the pair of slats. 
During reciprocation of the slats, the fines of particulate material work 
downward around the free side of each seal member and drop into the fines 
removal trough. As the adjacent slats move simultaneously in the load 
conveying direction, the adjacent side sections cooperate to move the 
fines in the trough in the same conveying direction to the discharge end 
of the trough. 
It is the principle objective of this invention to provide a reciprocating 
conveyor particularly suitable for the efficient conveying of solid 
particulate material. 
Another objective of this invention is the provision of a reciprocating 
conveyor of the class described in which means is included for allowing 
the escape and subsequent recovery of the fines of solid particulate 
materials. 
Still another objective of this invention is the provision of a 
reciprocating conveyor of the class described in which means is included 
for accelerating the movement of recovered fines of solid particulate 
materials to a recovery station. 
A further object of this invention is the provision of a reciprocating 
conveyor of the class described which is of simplified construction for 
economical manufacture, maintenance and repair.

DESCRIPTION OF THE PREFERRED EMBODIMENTS. 
In the embodiment illustrated in FIGS. 1 and 2, a base floor 10 of 
concrete, reinforced by angle irons 12, is shown to be elevated at an 
outfeed end 10' for access to the gravity outfeed of the conveyor by a 
truck, conveyor, or other suitable output conveyance. 
A plurality of laterally spaced, elongated, fines recovery troughs 14 of 
U-shaped cross-section are welded to the angle irons 12 and or otherwise 
secured to and supported by the base 10. As illustrated in FIG. 1, the 
troughs preferably project beyond the outfeed end 10' of the base. 
A plurality of laterally spaced, elongated, parallel, reciprocating 
conveyor slats of inverted U-shaped cross-section, each provide an 
intermediate, upwardly facing, load-supporting section 16 and laterally 
spaced, downwardly extending side sections 18 and 20. The side section 18 
of one slat and side section 20 of the next adjacent slat form a pair of 
mutually facing side sections, and each such pair is disposed above and in 
registry with an associated trough 14. 
An elongated seal member 22, shown as V-shaped in cross-section, is secured 
along its spaced edges to one side section, for example section 20, of 
each pair of mutually facing side sections, and spans the space 
therebetween, terminating at its apex in sliding contact or otherwise 
closely adjacent the other side section, for example section 18 of the 
mutually facing pair. 
As in my earlier patents mentioned previously, the conveyor slats are 
driven to reciprocate longitudinally on a sequence predetermined to move a 
load longitudinally in a conveying direction. This may be achieved by 
moving all of the slats simultaneously in the conveying direction and then 
moving each slat sequentially in the opposite, retracting direction. 
Alternatively, a majority of the slats may be moved simultaneously in the 
load conveying direction while the remaining slats are moved in the 
opposite, retracting direction. 
During movement of all or a majority of the slats in the conveying 
direction, any fines material that has filtered downward by gravity past 
the free side of seal member 22 into the trough 14, is moved by the pairs 
of mutually facing side sections 18, 20 in the same conveying direction, 
toward the outfeed end of the troughs 14. The fines dispensed from the 
outfeed ends of the troughs are collected either separately or in 
combination with the bulk of particulate material outfed by the slats. 
In the embodiment of FIGS. 1 and 2, means preferably is provided for 
assisting the outfeed movement of fines along the troughs. This means is 
provided by serrating the lower edges of the side sections 18 and 20 to 
form a series of wedge-shaped pusher members 24. The wide ends 24' of the 
pusher members face and are disposed substantially perpendicular to the 
conveying direction of movement of the slat members, whereby they function 
as blades to push the fines material in the troughs toward the outfeed end 
thereof. The sloping, trailing edges of the wedge-shaped pusher members 
merely push the fines material aside laterally during the retracting 
movement of the slats. 
In the embodiment illustrated in FIG. 3, each slat is supported by an 
elongated tubular support member 26 mounted on the floor base 10 in 
between adjacent troughs 14. A bearing member 28 of a material providing 
reduced co-effecient of friction, is interposed between each support 
member 26 and the overlying slat. The bearing member may extend the full 
length of the support member 26 and slat, in which case it may be secured 
either to the support member 26 or to the slat. Alternatively, the bearing 
member may be provided as a plurality of short sections secured at 
longitudinally spaced intervals to the support member 26. 
In the embodiment of FIG. 3, it is to be noted that the side sections 18 
and 20 of the slats are elevated out of sliding contact with the troughs 
14, whereby to eliminate wear of both components. The lower portions of 
the side sections preferably are provided with the same type of 
wedge-shaped pusher members 24 as in the embodiment of FIGS. 1 and 2. 
In the embodiment of FIGS. 4 and 5, each tubular support member 26 of FIG. 
3 is replaced with a pair of elongated I-beams 30 and 32 spaced apart 
laterally and underlying each slat. The bearing member 28 of FIG. 3 is 
replaced with a bearing member 34 for each I-beam. The bearing member 34 
is provided with resilient fingers 36 extending downwardly and angularly 
inward from opposite lateral sides of the bearing member for releasably 
clamping between them the opposite lateral sides of the associated I-beam. 
The laterally outer side of each bearing member 34 also is provided with an 
outwardly and downwardly extending resilient locking tab 38 arranged to 
releasably engage a locking ledge 40 on the confronting side section 18 or 
20 of the associated slat. The slat thus is secured releasably to the 
bearing member 34, and hence to the I-beams, against vertical 
displacement. 
The ledge 40 may be formed as a contoured inner surface of the side section 
18 or 20. In the preferred embodiment illustrated and best shown in FIG. 
4, the ledge is provided by an elongated resilient strap 42 secured at its 
opposite side edges, as by welding, to the intermediate section 16 and 
associated side section 18 or 20. Intermediate its sides, the strap is 
bent longitudinally to form the laterally projecting ledge 40 located 
adjacent the associated side section of the slat for cooperative 
association with the locking tab 38. 
In the embodiment of FIGS. 4 and 5, the wedge-shaped fines pusher members 
44 are provided by serrated strips secured to the lower ends of the side 
sections 18 and 20 and extending laterally outward, horizontally 
therefrom. The wide end 44' of each pusher member faces and is disposed 
substantially perpendicular to the conveying direction of movement of the 
slat members, as in the embodiment of FIGS. 1 and 2, to function as blades 
to push the fines material in the troughs toward the outfeed ends thereof. 
In this latter regard, it is to be noted in FIG. 5 that the adjacent pair 
of slats at the left side of the figure are moving simultaneously in the 
load conveying direction, as indicated by the arrows. During this 
movement, the pusher members 44 on the mutually facing side sections of 
the slats are arranged in alignment, whereby to cooperate in moving the 
fines material in the trough in the direction of load conveying movement 
of the slats. 
The slat at the right in FIG. 5 is shown by an arrow to be moving in the 
opposite, retracting direction. During this movement the fines material in 
the trough is moved laterally in the trough by the camming action of the 
tapered edge of each wedge-shaped pusher member. 
It will be understood that the foregoing fines removal operation of the 
horizontally disposed pusher members 44 is also produced by the vertically 
disposed pusher members 24 in the embodiments of FIGS. 1, 2 and 3. 
From the foregoing, it will be appreciated that the present invention 
provides a reciprocating conveyor especially suited to the conveyance of 
particulate materials, especially solids particulates of abrasive 
character such as sand, mineral ores, sewage and others. For some 
materials, such as sewage, it is preferred that the longitudinal dimension 
of the conveyor slats and associated components be disposed at a slight 
downwardly sloping angle to accommodate the gravity flow of the liquid 
component of sewage. 
It will be apparent to those skilled in the art that various changes may be 
made in the size, shape, type, number and arrangement of parts described 
hereinbefore, without departing from the spirit of this invention and the 
scope of the appended claims.