Apparatus and method for supplying articles to a conveyor

Articles are supplied to a conveyor by feeding primary articles from a primary supply, seriatim, to a conveyor. The conveyor is driven at a first speed consistent with the supply of primary articles so that primary articles are uniformly spaced on said conveyor. The presence of a predetermined number of supplemental articles in a supplemental supply is detected, and used to increase the speed of the conveyor to produce space on the conveyor sufficient to receive the predetermined number of supplemental articles. The predetermined number of supplemental articles are fed, seriatim, to the conveyor such that the supplemental articles are uniformly spaced on the conveyor with the same spacing that the primary articles on the conveyor.

TECHNICAL FIELD 
This invention relates to apparatus and method for supplying articles to a 
conveyor, and more particularly to apparatus and method for introducing 
supplemental articles into a conveyor line carrying primary articles. 
BACKGROUND ART 
Equipment for automatically packaging articles generally include sequential 
stations at which various assembly, packaging, and wrapping operations are 
effected, with automated inspection being carried out between stations. 
For example, in packaging cigarettes, the packages pass through a seal 
application station in which a sealing strip is applied across the top of 
each package before the package is conveyed to a wrapping station. For 
quality control purposes, inspection of each package is carried out 
between the station in which the seal strip is applied and the wrapping 
station in order to weed-out those packages with defective sealing strips. 
Where an automatic inspection process is employed, experience shows that 
some of the packages weeded out are actually satisfactory and can be 
returned to the main packaging line for wrapping. Furthermore, some 
defective packages can be reworked and returned to the packaging line. 
Ideally, those packages weeded out during inspection and later found to be 
satisfactory or reworked could be collected into a supplemental supply and 
reinserted into the main line downstream of the inspection station and 
before the line reaches the next packaging station. That is to say, spaces 
between packages in the main packaging line created by the diversion of 
packages as a result of an inspection, could be filled with packages from 
the supplemental supply. This approach, however, requires the inspection 
process to be highly synchronized with the movement of the main line. 
Where, for one reason or another, many possibly defective packages are 
detected in a given time period, and diverted from the main line, the 
inspection process cannot be completed in time to place those later 
packages found to be acceptable back into the line before the packages 
reach the next station. When this situation occurs, space in the main line 
is provided by halting the upstream operation of the packaging line 
providing the primary packages, a procedure that reduces productivity and 
requires manual intercession into an otherwise automatic process. 
It is therefore an object of the present invention to provide new and 
improved apparatus and method for introducing supplemental articles into a 
conveyor line carrying primary articles without stopping the line. 
BRIEF DESCRIPTION OF INVENTION 
A method according to the present invention for supplying articles to a 
conveyor includes the steps of supplying primary articles, seriatim, from 
a primary supply to a conveyor, and driving the conveyor at a first speed 
consistent with the supply of primary articles so that the latter are 
uniformly spaced on said conveyor. The presence of a predetermined number 
of supplemental articles in a supplemental supply is detected; and, the 
speed of the conveyor is increased in response to such detection, to 
produce space on the conveyor sufficient to receive the predetermined 
number of supplemental articles. At this point, the predetermined number 
of supplemental articles are supplied, seriatim, to the conveyor so that 
the supplemental articles are uniformly spaced on the conveyor with the 
same spacing as the primary articles on the conveyor. 
In the preferred embodiment of the invention, the supply of primary 
articles is stopped in response to detection of the presence of the 
predetermined number of supplemental articles in the supplemental supply. 
After the predetermined number of supplemental articles are supplied to 
the conveyor, the speed of the conveyor is decreased to the first speed 
simultaneously with the resumption of the supply of primary articles to 
the conveyor. The present invention thus provides for the automatic 
introduction of supplemental articles into a conveyor line carrying 
primary articles without the need for manual intercession.

DETAILED DESCRIPTION 
Before discussing the details of the present invention illustrated in FIGS. 
1-4, reference is made to FIG. 5 for the purpose of providing an overview 
of the invention in order to better appreciate the interaction between 
various components of the invention, and to provide an understanding of 
its overall operation. As shown in FIG. 5, reference numeral 100 
designates apparatus according to the present invention, such apparatus 
comprising conveyor 11 carried by drive roller 12 which is driven by drive 
means 13 at either a low speed or a high speed depending upon the state of 
control means 101. Primary articles a accumulated in supply 2 are fed by 
mechanism 3 onto conveyor 11 when mechanism 3 is operated by drive means 
3. Schematically, the control of the operation of mechanism 3 by the drive 
means is illustrated by switch 102. That is to say, drive means 13 
operates feed mechanism 3 only when switch 101 is closed, a condition of 
the switch that exists only when the drive means operates the conveyor at 
its low speed. In actual practice, switch 102 is constituted by an 
mechanical arrangement that couples a driving motion to mechanism 3 only 
when the conveyor is operated at low speed. 
When detector 5 detects a predetermined number of supplemental articles a' 
in supply 4, the output of the detector causes control means 101 to effect 
three operations: (1) drive means 13 is commanded to increase the speed of 
the conveyor for a selected period of time; (2) the operation of feed 
mechanism 3 is interrupted (by opening switch 102) for such period of 
time; and (3) feed mechanism 6 is operated for such period of time. The 
interruption in the operation of feed mechanism 3 coupled with an increase 
in speed of the conveyor serves to create a space on the conveyor large 
enough to accept the predetermined number of supplemental articles a' fed 
to the conveyor by the operation of mechanism 6. 
After the predetermined number of supplemental articles are fed to the 
conveyor, control means 101 effects the reversal of the three operations 
described above. That is to say, control means 101 interrupts operation of 
supplemental feed mechanism 6, commands drive means 13 to run the conveyor 
at its original speed, and resumes operation of feed mechanism 3. In this 
way, a predetermined number of supplemental articles are automatically 
inserted into a moving conveyor line of primary articles. 
Referring now to FIG. 1, apparatus according to the present invention 
includes conveyor line 1 having spaced guides 10 supporting conveyor belt 
11 which carries a plurality of transverse pusher bars 11' evenly spaced 
along the length of the conveyor. Belt 11 mounted on a pair of rollers, 
roller 12 constituting the drive for the conveyor which moves in the 
direction indicated by the arrows in FIG. 1. Drive roller 12 is connected 
through transmission mechanism 13 (FIG. 2) to drive shaft 14 whose 
rotation is synchronized with operation of an upstream packaging process 
which supplies packages a to conveyor 11. 
As seen in FIG. 1, packages a are supplied from the upstream packaging 
operation by conveyor 15 which delivers the packages to magazine 16 of 
primary supply 2. Pusher 18 causes the packages to be stacked in the 
magazine which is in the form of a vertically oriented tube whose 
crosssection matches the cross-section of packages a. The bottom of the 
magazine is provide with stop-flange 17' for forming a ledge that supports 
the vertical stack of packages. Adjacent the bottom of the tube of 
magazine 16 is an opening in the side of the tube for receiving the free 
end of pusher arm 19 of feed mechanism 3. The other end of the pusher arm 
is pivotally connected to drive lever 20 which oscillates in accordance 
with the rotation of shaft 13' of transmission 13. That is to say, one 
revolution of shaft 13' is mechanically converted to one oscillation of 
lever 20 and thus one stroke of pusher arm 19. In addition, one revolution 
of shaft 13' results in the linear displacement of the conveyor through a 
distance equal to the spacing between adjacent pusher bars 11'. 
The free end of pusher arm 19 passes through the opening in the bottom of 
the vertical tube of magazine 16 when lever 20 oscillates, and engages the 
lowermost package resting on stop-flange 17' moving this package out of 
engagement with the stop-flange and into alignment with opening 17 which 
constitutes a supply port through which the displaced package drops by 
gravity onto conveyor 11. The synchronized operation of drive lever 20 
with the movement of conveyor 11 is such that primary feed mechanism 3 
deposits a single package a onto conveyor 11 each time a pusher bar 11' 
passes magazine 16. In this manner, primary feed mechanism 3 is responsive 
to the operation of the conveyor at a first speed for feeding packages a, 
seriatim, from the primary supply to the conveyor so that the packages 
from this magazine are uniformly spaced on the conveyor. 
Downstream from primary supply 2, is supplemental supply 4 constituted by a 
downwardly sloping tube 21 which acts as a magazine that receives and 
stores supplemental packages a' which may be packages extracted from 
conveyor 15 upstream of the apparatus shown in FIG. 5, inspected, and then 
made available for reinsertion into main line 1. 
Tube 21 has, at its lower end, stop-flange 23' which forms a stop and 
engages packages a' permitting these packages to be stacked in the hopper. 
To one side of this hopper is pusher arm 25 to one of which is pivotally 
mounted drive lever 26. When drive lever 26 is oscillated as shown by the 
arrow in FIG. 4, the free end of the pusher arm enters opening 24 at the 
bottom of tube 21, engages package a' resting on flange 23', and displaces 
this package into alignment with opening 23 in the bottom on tube 21 
thereby allowing the displaced package to drop by gravity onto conveyor 
11. 
Drive lever 26 is not oscillated, however, until after sensor 5 senses a 
predetermined number of supplemental packages a' in tube 21. In FIG. 1, 
sensor 5 is vertically located above flange 23' a distance equal to the 
height of five packages stacked in tube 21. This height is arbitrary, 
however, and could be made equal to the height of any number of packages. 
When the predetermined number of packages is sensed by sensor 5, motor M 
(FIG. 2) is operated causing speed-change gears 7 of transmission 
mechanism 13 to speed-up the rotation of drive roller 12 thereby 
increasing the linear speed of conveyor 11. Simultaneously, the operation 
of drive lever 20 associated with primary feed mechanism 3 is disabled. In 
addition, the sensing of a predetermined number of supplemental packages 
in hopper 21 is accompanied by the initiation of oscillation of drive 
lever 26 of supplemental feed mechanism 6 which continues until five 
articles are fed from supply 4 to the conveyor. 
As a consequence of the termination of the supply of primary articles by 
primary feed mechanism 3, and the speeding up of the rotation of drive 
wheel 12, spaces S develop in the conveyor to provide clearance in the 
form of spaces S into which supplemental packages a' are deposited. 
In operation, packages produced by a previous packaging operation are 
supplied to conveyor 15 to hopper 16 of primary supply 2. The linear 
displacement of conveyor belt 11 is accompanied by the regular oscillation 
of drive lever 20 for the purpose of inserting primary articles a into 
receptacles defined by pusher plates 11' on the conveyor such that primary 
packages are delivered uniformly on the conveyor. Supplemental articles, 
as they are produced, are added to hopper 21. When the number of 
supplemental articles in hopper 21 reaches a predetermined number, this 
situation is sensed by sensor 5 which decouples transmission 13 from drive 
lever 20, and at the same time increases the linear speed of the conveyor. 
The resultant empty receptacles formed by pusher plates 11' are filled by 
the operation of drive lever 26 which commences in synchronism with the 
increase in linear speed of the conveyor and the termination of the 
operation of drive lever 20 of primary feed mechanism 3. In this manner, 
the predetermined number of supplemental packages a' are inserted into 
conveyor line 1. 
The advantages and improved results furnished by the method and apparatus 
of the present invention are apparent from the foregoing description of 
the preferred embodiment of the invention. various changes and 
modifications may be made without departing from the spirit and scope of 
the invention as described in the claims that follow.