Merging or blending techniques for small parts

The invention relates to methods and means for combining two merging streams of small parts having heads and shanks comprising progressing each of the streams in the same general direction and with the heads aligned and the shanks transverse to the direction of progression. The streams, or paths, are lead at different levels and in different horizontal positions at the last part of the progression and then the streams or paths are progressively merged at the last part of the progression in at least the horizontal direction so the shanks of the parts in one path become interposed between the heads of the parts in the other path as the paths are merged into a single path without stoppage.

BACKGROUND OF THE INVENTION 
1. Field of Invention 
The invention relates to methods and means for combining two merging 
streams of parts having heads and shanks so that the merged paths coincide 
without stoppage. 
2. Description of the Prior Art 
In the prior art there have been many devices for handling small parts. 
Brewer U.S. Pat. No. 3,156,342 discloses feeding rivets by a plurality of 
chutes which merge in a single chute. Brown et al U.S. Pat. No. 3,638,260 
discloses the assembly of screw blanks and washers prior to threading the 
blanks. In Brown, there are two chutes, one for the screw blanks and one 
for the washers and the washers and the screw blanks are combined. Cooley 
et al U.S. Pat. No. 3,323,155 discloses pneumatic means for propelling 
small parts. 
Moncrieff U.S. Pat. No. 2,889,023 discloses an apparatus for orienting 
asymmetrical cylindrical gears wherein the gears fall into one of two 
receiving troughs arranged in opposite semicircular relation to each 
other. The troughs, at the ends thereof, are arranged such that an upper 
trough directly overlies the lower trough and, therefore, the gears 
rolling in the upper trough fall downwardly into the lower trough to 
effect merger in the lower trough. 
The conventional method of combining separate streams of similar things, as 
illustrated by the disclosure of Brown, is adequate for small pieces and 
for relatively slow speeds of 60 pieces per minute. However, above such 
speeds the pieces tend to restrict one another from flowing into a single 
track and tend to occupy the same space at the same time, producing 
stoppages and irregularities of feeding. 
Accordingly, a new and improved method and means is desired for merging or 
blending two streams of small parts having a head and a shank into a 
single stream without stoppage. 
SUMMARY OF THE INVENTION 
This invention may be summarized as providing methods and means for 
combining two merging streams of small parts having heads and shanks 
comprising progressing each of the streams in the same general direction 
and with the heads aligned and the shanks transverse to the direction of 
progression. The streams, or paths, are lead at different levels and in 
different horizontal positions at the last part of the progression and 
then the streams or paths are progressively merged at the last part of the 
progression in at least the horizontal direction so the shanks of the 
parts in one path become interposed between the heads of the parts in the 
other path as the paths are merged into a single path without stoppage. 
Among the advantages of the subject invention is a provision for a new and 
improved method for combining streams or paths of small parts having a 
head and a shank without stoppage. 
An objective of this invention is to provide a means for progressively 
simultaneously merging the end portions of vertically and horizontally 
misaligned paths of small parts having a head and a shank in both the 
vertical and horizontal directions so the shanks of the parts in one path 
continuously become interposed between adjacent heads of the parts in the 
other path. 
The above and other objectives and advantages of this invention will be 
more fully understood and appreciated with reference to the following 
detailed description and drawings appended hereto.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
In the invention, two streams of identical parts are moved along paths 
having the heads aligned and having the shanks transverse to the direction 
of progression. The parts are preferably transported by pueumatic means 
along guideways and the preferred orientation is to put the head above and 
the shank vertically below. 
These guideways are vertically misaligned so that one guideway at the 
latter part of the path, at least, will lie in a plane above the other 
guideway. The latter part of the guideways are also horizontally 
misaligned, but generally proceeding in the same direction. At the point 
of merger, the paths are progressively brought into coincidence, so that 
the shank of a part on one path is inserted between the heads of adjacent 
parts in the other path. Thereafter the inserted shank will move 
downwardly, with respect to the adjacent heads such that all of the heads 
are horizontally aligned in the same plane. 
The parts such as screws, screw blanks, rivets and the like 20 have heads 
22 and shanks 24. The heads 22 are preferably curved semispheres or 
filleted at the edges with generally planar bottom surfaces. The shanks 24 
are generally cylindrical or tubular in configuration and extend from the 
center of the bottom surface of the head 22. 
As illustrated in the drawings, the parts 20 are progressed along two paths 
26 and 28 by means such as pneumatic jets 30 or by producing movement of 
the guideways by oscillation, vibration or jiggling. The paths 26 and 28 
are preferably created by guideways 32 and 34. These guideways 32 and 34 
may be provided with roofs 36. 
The guideway 32 is permissibly of downwardly sloping form while the 
guideway 34 proceeds in the same general direction at a higher level and 
also preferably in a somewhat diverging path. The higher guideway 34 need 
only be progressively horizontally merged with the lower guideway 32 
provided that the shanks 24 of the parts in the upper guideway 34 extend 
downwardly a sufficient distance to insure that these shanks 24 are 
interposed between the heads 22 of the parts 20 in the lower guideway 32 
as horizontal merger is accomplished. Alternatively, the higher guideway 
34 may extend downwardly at 38 and may converge progressively 
simultaneously in both the vertical and horizontal directions toward the 
other guideway 32 to form a single meshed guideway 40. 
At the point 42 where the coincidence of the two guideways 32 and 34 
begins, there may be a gradual or an abrupt change in the level of the 
parts 20 in the upper guideway 34. At that point 42 the guideway 40 
begins, and a pneumatic jet 46 may be provided to propel the parts along 
the guideway 40. As shown in FIGS. 4 and 5, the change in level and 
direction of the parts in the upper guideway 34 with respect to the lower 
guideway 32 is sufficient to allow the shank 24 of a part 48 from the 
upper guideway 34 to become interposed between, and in abutting 
relationship with, the heads 22 of the previously adjacent parts 50 and 52 
in the lower guideway 32 without stoppage. It would be apparent to those 
skilled in the art that this may be accomplished by providing a slope 
which may vary with the size, weight and configuration of the parts being 
merged. It should also be apparent that merger may be accomplished without 
changing the slope of either guideway at the last part of progression. For 
example, the parts 20 in the upper guideway 34 vertically and horizontally 
misaligned with the parts 20 in the lower guideway 32 may be merged just 
in the horizontal direction as long as the maintained vertical 
misalignment is such that the shanks 24 of the parts 20 in the upper 
guideway 34 become interposed between the heads 22 of the parts 20 in the 
lower guideway 32 without stoppage. 
Thus, the parts which were preceding along the end portions of the upper 
and lower guideways are made to merge by interposing the shank 24 of a 
part 48 from the upper guideway 34 between the heads of two adjacent parts 
50 and 52 in the lower guideway before the heads from both guideways are 
finally brought into horizontal alignment. As shown in FIGS. 4 and 5 the 
head 22 of the part 48 from the upper guideway 34 overlies the heads 22 of 
the adjacent parts 50 and 52 in the lower guideway 32. The head 22 of a 
part 54 from the upper guideway 34 may continue to overlie the heads 22 of 
the previously adjacent parts 52 and 56 from the lower guideway 32 for 
some time after the parts are merged in guideway 40. After the shank is 
interposed between the heads in the lower guideway, the merger of the 
parts proceeds to complete vertical and horizontal alignment whereby the 
shank of the part 48 proceeds downwardly with respect to the heads of the 
parts 50 and 52. After the head of the part 48 overlies the heads of the 
parts 50 and 52, the head of the higher part 48 will drop between the 
heads of the lower parts 50 and 52 while maintaining continuous 
progression of the parts without stoppage. As shown in FIG. 5, the head 22 
of the part 58 which was fed from the upper guideway 34 has dropped into 
complete horizontal alignment between the heads 22 of the previously 
adjacent parts 56 and 60 which were fed from the lower guideway 32. 
Thus, screw blanks which were fed separately at 1000 blanks per minute were 
combined into a single stream which handled without incidence 2000 blanks 
per minute which necessarily did not result in stoppage or other feeding 
irregularities. 
The exact contour of the two merging tracks may be varied to suit the 
conditions. For example, the beginning or middle portions of the guideways 
may or may not be in vertical alignment or horizontal alignment depending 
upon various operating conditions. However, this invention requires that 
the end portions of the merging guideways, or the last part of progression 
of the paths, just prior to the point of merger, be horizontally and 
vertically misaligned. With such construction, the end portions of the 
merging guideways or paths may be progressively merged in at least the 
horizontal direction into a merged guideway in which both sets of parts 
are finally brought to the same level and to the same horizontal path. 
Whereas the particular embodiments of this invention have been described 
above for purposes of illustration, it will be apparent to those skilled 
in the art that numerous variations of the details may be made without 
departing from the invention.