Apparatus for aligning vessels

An apparatus for aligning vessels comprises a robot for delivering a vessel from a first conveyor to a second conveyor, a camera disposed on a path of conveyance of the first conveyor for photographing a manner of placement of vessels thereon, and correction device mounted on the second conveyor for erecting a vessel assuming a horizontal position when it is released by the robot. Any change in the size of a vessel does not require a remodelling of components of the apparatus, thus providing a vessel aligning apparatus having a high versatility.

FIELD OF THE INVENTION 
The invention relates to an apparatus for aligning vessels, and more 
particularly, to such apparatus which utilizes a robot. 
Description of the Prior Art 
An apparatus for aligning vessels sequentially in a given direction as they 
are supplied at random is disclosed, for example, in Japanese Patent 
Publication No. 57,004/1989. 
The disclosed apparatus comprises a discharge conveyor and a chute which is 
disposed over the discharge conveyor and extending vertically upward, the 
chute having a feed port at its upper end through which vessels are 
supplied sequentially and at random. The chute is internally provided with 
a stop against which a vessel is temporarily supported, and is 
successively aligned by an engaging plate and a support member which are 
disposed below the stop. Specifically, when the vessel is released from 
the support by the stop, it then drops until its top end or bottom end is 
engaged by the support member which assumes an advanced position. As the 
support member retracts to its retracted position, a barrel portion of the 
vessel supported by the support member is engaged with the engaging plate. 
If the vessel is engaged with the engaging plate in its erected condition, 
the vessel is allowed to pass while maintaining its erected position, but 
in the event the vessel is engaged with the engaging plate in its inverted 
condition, the vessel is reversed into its erected position before it 
falls onto the discharge conveyor. With this arrangement, the vessels, 
which are supplied into the chute at random, are aligned with each other 
and assume an erected position having its top end oriented upside after 
they have fallen through the chute to be placed on the discharge conveyor. 
However, in a conventional apparatus as mentioned above, if the size of 
vessels to be processed is changed, the chute as well as other components 
must be changed in accordance with the new size of the vessel, resulting 
in a troublesome remodelling operation. 
In view of the foregoing, the present invention provides an apparatus for 
aligning vessels comprising a first conveyor for conveying vessels which 
are supplied at random, a second conveyor located adjacent to the first 
conveyor for conveying the vessels, a camera disposed on the path of 
conveyance of vessels on the first conveyor for photographing the manner 
of placement of a vessel thereon, a robot responsive to the camera for 
aligning a vessel on the first conveyor into a given direction and 
delivering it from the first to the second conveyor, and correcting means 
disposed on the path of conveyance of vessels on the second conveyor for 
erecting a vessel conveyed on the second conveyor. 
With this arrangement, no remodelling operation of components are required 
if the size of vessels to be processed is changed. Accordingly, the 
apparatus can be used with vessels having sizes which vary in a given 
range, thus improving the versatility thereof. 
Above and other objects, features and advantages of the invention will 
become apparent from the following description of several embodiments 
thereof with reference to the attached drawings.

DETAILED DESCRIPTION OF EMBODIMENTS 
Several embodiments of the invention will now be described with reference 
to the drawings. Initially referring to FIG. 1, an apparatus 1 for 
aligning vessels is adapted to erect vessels 3, which are supplied onto a 
first conveyor 2 in their horizontal positions, into upright position and 
align them in a single longitudinal row. 
The vessel 3 in this embodiment comprises a generally cylindrical plastic 
vessel having a circular cross section, and a mouth 3a projects centrally 
from the top end of the vessel while its bottom 3b is formed as a flat 
surface. 
A hopper 4 represents a reservoir of vessels 3, and a feeder 5 which is 
disposed at an angle for running along a circulating path successively 
takes out vessels from within the hopper 4 and drops them onto a chute 6 
which is located adjacent to an upstream end of the first conveyor 2. 
As shown in FIGS. 3 to 6, in the present embodiment, the chute 6 is 
disposed to be inclined so that the elevation of its downstream end is 
lowest. On the other hand, the upper region of the chute 6 is corrugated 
in section so as to form a plurality of guide grooves 6a extending 
parallel to the running direction of the first conveyor 2. In the lower 
region, the surface of the chute 6 is provided with sliding guides 6b in 
the form of rods having a triangular cross section, which are parallel to 
each other and which are spaced apart in a manner commensurate with the 
width of each guide groove 6a. A plurality of engaging brushes 8 and 
engaging rollers 9, which are driven for rotation by a mortor 7, are 
disposed over the respective guide grooves 6a at an intermediate position 
along the length thereof. 
Accordingly, the vessels 3 which are successively taken out of the hopper 4 
by the feeder 5 and dropping onto the chute 6 initially move along the 
sliding guides 6b before they are supplied onto the first conveyor 2. If a 
plurality of vessels 3 overlap each other in the guide groove 6a of the 
chute 6, the upper one of such vessels 3 will be engaged by the brush 8 
and the roller 9, which are effective to eliminate such overlapping 
relationship. In this manner, individual vessels 3 will be supplied onto 
the first conveyor 2 in a single tier and as oriented parallel to the 
direction of the first conveyor 2. 
A robot 13 associated with a controller 12 which controls its operation is 
disposed along one side of the first conveyor 2 at its downstream end. The 
upstream end of a discharge conveyor 14 is located on the opposite side of 
the first conveyor 2 from the robot 13, and is associated with correction 
means 15 which is effective to erect the vessel 3 from their horizontal to 
their upright position. 
The robot 13 is operative to catch a vessel 3 on the first conveyor 2 at 
catch position A which is predefined on the first conveyor 2, to move it 
to a release position B which is predefined on the discharge conveyor 14, 
and to release the vessel which it has caught to allow it to drop onto the 
discharge conveyor 14 at the release position B. Upon falling onto the 
discharge conveyor 14, the vessel 3 is engaged with the correction means 
15, whereby it is erected to its upright position from its horizontal 
position. A rotary encoder 17' is connected to the connection means 15. 
A CCD camera 16 is disposed over the path of conveyance of the first 
conveyor 2, at a point upstream of the location of the robot 13, for 
photographing the manner of placement of each individual vessel 3 as it is 
conveyed on the first conveyor 2 for feeding the resulting picture signal 
to the controller 12. A rotary encoder 17 is connected to the downstream 
end of the first conveyor 2 to detect a pulse signal, which is also input 
to the controller 12. 
As will be described later in detail, the controller 12 is operative to 
cause a reciprocating movement of the robot 13 between the catch position 
A and the release position B based on the picture of the vessel 3 as 
supplies from the CCD camera 16 and the pulse signal from the rotary 
encoder 17, 17'. 
Referring to FIG. 2, the robot 13 according to the present embodiment 
comprises a vertically oriented first drive shaft 21 having an increased 
diameter, the top end of which is connected with one end of a horizontally 
disposed first arm 22. The other end of the first arm 22 rotatably carries 
a vertically oriented second drive shaft 23, which is in turn connected 
with one end of a horizontally oriented second arm 24. The other end of 
the second arm 24 rotatably carries a third drive shaft 25 of a reduced 
diameter, the lower end of which has a processing head 26 mounted thereon. 
As shown in FIG. 7, the processing head 26 includes a support member 27 in 
the form of a rectangular plate, which is connected to the bottom end of 
the third drive shaft 25 at its center lengthwise so as to be supported in 
a horizontal position. Accordingly, as the third drive shaft 25 rotates, 
the support member 27 can be rotated in either direction in a horizontal 
plane. 
The support member 27 includes a longitudinal centerline C, and a pair of 
air cylinders 28, 29 are mounted on the bottom surface of the support 
member 27 at an equal distance from the center or the location where the 
support member is connected to the third drive shaft 25 along the 
centerline C. Each air cylinder 28, 29 is directed vertically downward and 
includes a piston, the lower end of which has a vacuum pad 32 mounted 
thereon, which serves as a catcher. In the present embodiment, these 
vacuum pads 32 are effective to hold, by attraction, the outer periphery 
of the vessel 3, at a location slightly displaced toward the bottom 3b 
from the center along the length thereof (see FIGS. 8 and 9). 
The operation of each air cylinder 28, 29 is controlled by a control unit 
12A of the controller 12 so that when each air cylinder 28, 29 is 
inoperative, the associated vacuum pad 32 is located at its elevated end 
while when it is operated, each vacuum pad 32 moves down to its lowermost 
position. The supply and interruption of a negative pressure supplied to 
the vacuum pad 32 is also controlled by the control unit 12A. The control 
unit 12A is operative to introduce a negative pressure into the respective 
vacuum pad 32 during its movement from the catch position A to the release 
position B where it releases the vessel 3, and ceases to introduce the 
negative pressure to the vacuum pad 32 from the time when it has released 
the vessel 3 at the release position B until it returns to the catch 
position A. Accordingly, the vessel 3 which has been held by the vacuum 
pad 32 is allowed to drop onto the downwardly located discharge conveyor 
14 at the release position B. 
In addition to the control unit 12A, the controller 12 also includes a data 
memory 12B, which has pre-stored data for causing the vacuum pad 32 of the 
respective air cylinder 28, 29 to hold the vessel 3, by attraction, a the 
catch position A in a manner such that the lengthwise direction of the 
vessel 3 in its horizontal position is perpendicular to the lengthwise 
direction of the support member 27 and such that the vessel 3 is held by 
attraction by the vacuum pad 32 at a location which is offset from the 
center of the length thereof toward the bottom 3b as mentioned above. 
The control unit 12A of the controller 12 is operative to control the 
operation of the processing head 26 of the robot 13 in a manner to be 
described below, while comparing signals fed from the CCD camera 16 and 
the rotary encoder 17 against the pre-stored data in the data memory 12B. 
Specifically, when the picture of a leading one, 3', of the vessels, the 
picture of which has been taken by the CCD camera 16, is fed to the 
controller 12 as illustrated in FIG. 8(a), the control unit 12A compares 
the picture of the leading vessel 3' against the direction indicated by 
data stored in the data memory 12B, and moves the processing head 26 to a 
point where the leading vessel 3' can be held attracted with the 
perpendicular relationship with respect to the support member 27. As 
mentioned previously, in the present embodiment, the vessels 3 which are 
placed on the first conveyor 2 are carried while maintaining its 
substantially parallel relationship with the direction of conveyance of 
the first conveyor 2, so that the support member 27 will be supported so 
as to be perpendicular to the first conveyor 2 at the catch position A. 
Thereupon, the control unit 12A causes the vacuum pad 32 to move down in 
order to hold the leading vessel 3' by attraction. 
By this time, the picture of a second one of the vessels 3, as taken by the 
camera 16, will have been fed to the controller 12, and accordingly, the 
control unit 12A causes the processing head 26 to be slightly displaced in 
the direction perpendicular to the first conveyor 2 before it causes the 
other vacuum pad 32 to move down, thus allowing the second vessel 3 to be 
held by the other vacuum pad 32 by attraction. 
In this manner, when the leading vessel 3' and the second vessel 3 are held 
attracted by the vacuum pads 32 of the both cylinder units 28, 29, the 
mouths 3a', 3a of these vessels 3', 3 may be located on the same side, or 
on the opposite sides as shown in FIG. 8(b), as viewed in the longitudinal 
direction of the conveyor. This eliminates the need for a substantial 
rotation of the support member 27 in order to allow it to catch the second 
vessel 3 after it has held attracted the leading vessel 3', and what is 
required of the support member 27 is a translational movement through a 
given stroke. This allows a pair of vessels to be rapidly caught by the 
vacuum pads 32 of the both cylinder units 28, 29. 
On the other hand where it is desired to cause the mouths 3a of the vessels 
3 to be always located on one side as viewed longitudinally, it is 
required that at least the support member 27 be rotated through one-half 
revolutions, increasing a waiting time until the vessel 3 can be held 
attracted to thereby retard the processing speed. 
Alternatively, an arrangement may be made such that as soon as the vessel 
3' is held attracted, the vacuum pad 32 which carries such vessel 3' is 
raised to its elevated end in order to avoid an interference of the vessel 
3' thus carried with another vessel 3 on the first conveyor 4 as the 
processing head 26 is moved in order to catch a second one 3 of the 
vessels. 
When the pair of vessels 3', 3 are caught at the catch position A by the 
pair of vacuum pads 32 of the processing head 26, the control unit 12A is 
operative to cause a movement of the processing head 26 to the release 
position B shown in FIG. 9. At this time, the support member 27 extends 
parallel to the direction of the discharge conveyor 14 and is located over 
the discharge conveyor 14 at a central position crosswise. In this manner, 
the pair of vessels 3', 3 are located over the discharge conveyor 14, 
while it is supported horizontally, so as to be perpendicular to the 
conveyor 14. The control unit 12A then ceases to supply the negative 
pressure to the vacuum pads 32 at the release position B, whereby these 
vessels 3', 3 are simultaneously released to drop down, and are then 
reversed, as required, by the correction means 15. 
After releasing the vessels 3', 3 the processing head 26 returns from the 
release position B to the catch position A, and operates to hold, by 
attraction, a third and a fourth vessel on the first conveyor 2. 
As illustrated in FIGS. 2 and 10, the vessel receiving surface of the 
discharge conveyor 14 where the release position B is defined is located 
at a lower elevation than the vessel receiving surface of the first 
conveyor 2, and the correction means 15 is disposed so as to cover the 
upstream end of the discharge conveyor 14. 
As shown in FIG. 9, the correction means 15 comprises a pair of laterally 
spaced engaging members 33, 34 which are maintained to be parallel to each 
other and to be horizontal by means of brackets, and a continuous run of a 
multiplicity of buckets 35 which are disposed below the engaging members 
33, 34 so as to move along a circulating path along the discharge conveyor 
14 for preventing the turn-over of the erected vessels 3. The engaging 
members 33, 34 are in the form of rods, and the spacing therebetween is 
chosen to be slightly greater than the axial length of the vessel 3 except 
for its mouth 3a. The buckets 35 are mounted at an equal interval on a 
pair of upper and lower chains 36, which run in a direction indicated by 
an arrow along a circulating path. The buckets move along the discharge 
conveyor 14 in a space between the both engaging members 33, 34 and the 
vessel receiving surface of the discharge conveyor 14. 
Referring to FIG. 9, it will be seen that in the present embodiment, the 
both vessels 3', 3 which have been carried to the release position B will 
be located such that the outer periphery thereof which is disposed nearer 
the associated mouth 3a', 3a is disposed perpendicular to one of the 
engaging members 33 or 34 while the bottom 3b', 3b does not cross either 
engaging member 33 or 34. Since the both vessels 3', 3 are simultaneously 
released under this condition, it will be seen from FIG. 9 or 10 that only 
the outer periphery which is disposed nearer the mouth 3a' or 3a will bear 
against one of the engaging members 33 or 34 while the outer periphery 
located nearer the bottom 3b' or 3b cannot engage the other engaging 
member 33 or 34, and hence the vessel falls down in the space between the 
both engaging members 33, 34. In this manner, the vessels 3', 3 which have 
been in their horizontal position will be rotated so as to bring their 
mouths 3a', 3a oriented upward, and fall into the adjacent buckets 35 
while assuming such position. 
In the present embodiment, a drop guide 37 in the form of a plate having 
its upper portion inclined extends from substantially the lateral center 
of the discharge conveyor 14 to a point near and below the left-hand 
engaging member 33 (see FIG. 10) so that the bottom 3b' or 3b of the 
vessel 3' or 3 which falls down between the both engaging member 33, 34 as 
it is rotated in the manner mentioned above initially abuts against the 
upper skewed portion of the drop guide 37 and then falls down in sliding 
contact with the lower vertical portion of the drop guide. In this manner, 
it is assured that each vessel 3', 3 is placed on the discharge conveyor 
14 in its erected position with its mouth 3a' or 3a oriented vertically 
upward. 
When the vessels 3', 3 are placed on the discharge conveyor 14 in this 
manner, they will be aligned into a single longitudinal row and in its 
erect position having their mouths 3a directed upward so as to be 
delivered into a next processing step. 
In the described embodiment, the vessels are maintained in parallel 
relationship with each other as they are caught by the vacuum pads 32 of 
the robot 13 at the catch position A, regardless of either mouth 3a or 
bottom 3b is located on a given longitudinal side. Since the vessels 3 are 
conveyed by the conveyor 2 while maintaining their parallel relationship 
with the direction of conveyance of the conveyor 2, there is substantially 
no need to rotate the support member 27 of the processing head 6 when each 
vacuum pad 32 operates to catch the vessel 3. In this manner, the vessel 3 
can be very rapidly caught at the catch position A. The pair of vessels 3 
are simultaneously released at the release position B, and accordingly, 
the apparatus of the invention obtains a greater throughput. 
It will be seen that in the described embodiment, if the size of the 
vessels 3 to be processed is changed, there is no need for remodelling the 
components of the apparatus 1, thus providing a very versatile apparatus 
1. 
While the chute 6 has been used to orient the vessels 3 in the direction of 
conveyance of the conveyor 2 as they are supplied onto the conveyor 2, the 
provision of the chute 6 may be eliminated and vessels 3 having random 
orientations may be placed on the first conveyor 2. 
Second Embodiment 
FIGS. 11(a)-11(c) is a schematic illustration of a second embodiment of the 
invention. In the first embodiment mentioned above, the vessel 3 has been 
held by the vacuum pad 32 at a location which is offset from the center of 
the length of the vessel 3 toward the bottom 3b. However, in the second 
embodiment, the vessel 3 is held by the vacuum pad 32 at its lengthwise 
center (see FIG. 11(a)). When the pair of vessels 3 thus held are released 
at the release position B, the support member 27 is initially positioned 
at a first release position where the outer periphery nearer the mouth 3a 
of the first vessel 3, which has its mouth 3a disposed on the left-hand 
side, extends perpendicular to the left-hand engaging member 33, whereupon 
the first vessel is released (see FIG. 11(b)). Then, the support member 27 
is moved to a second release position where the outer periphery nearer the 
mouth 3a of the second vessel 3, which has its mouth 3a disposed on the 
right-hand side, extends perpendicular to the right-hand engaging member 
34, whereupon the second vessel is released (see FIG. 11(c)). 
If the both vessels 3 have their mouths 3a located on the left- or 
right-hand side, the processing head 26 may be sequentially moved to the 
first and the second release position. Again a similar effect is achieved 
as in the first embodiment. 
Third Embodiment 
FIGS. 12(a)-12(c) is a schematic illustration of a third embodiment of the 
invention where the pair of left and right engaging members 33, 34 used in 
the previous embodiments are replaced by a single engaging member 33 which 
is located over the centerline of the discharge conveyor 14. When the 
vacuum pad 32 is used to hold the vessel 3, the vessel 3 may be held at 
any location lengthwise thereof. At the release position B, the processing 
head is initially brought to a first release position where the outer 
periphery nearer the mouth 3a of the first vessel 3, which has its mouth 
3a disposed on the right-hand side, extends perpendicular to the engaging 
member 33, whereupon the first vessel 3 is released (FIG. 12(b)). Then the 
processing head is brought to a second release position where the outer 
periphery nearer the mouth 3a of the second vessel 3, which has its mouth 
3a disposed on the left-hand side, to cross perpendicular to the engaging 
member 33, whereupon the second vessel 3 is released (FIG. 12(c)). As a 
result of such arrangement, the vessel 3 may be held at any location at 
the catch position A. The third embodiment achieves the similar 
functioning and effect as achieved by the previous embodiments. 
Fourth Embodiment 
FIGS. 13 to 15(a)-15(d) show a fourth embodiment of the invention where 
correction means 115 comprises a conveyor 141, and pairs of left and right 
engaging members 142, 143, 144 which are disposed over the conveyor 141. 
Vertical plate members 145 are fixedly mounted on the vessel receiving 
surface of the conveyor 141 at an equal interval as viewed in the 
direction of conveyance for defining pockets therebetween. 
Each pair of engaging members 142, 143, 144 located at the release position 
B is supported so as to be spaced apart by a distance slightly less than 
the axial length of a vessel 103 and so as to be located at an elevation 
below the external diameter of the vessel which assumes its horizontal 
position in the most upstream region of the conveyor 141, but the more 
they are located downstream, the spacing between the members of each pair 
is gradually reduced while their elevation is increased. 
Therefore, it will be seen from FIG. 14 where a pair of vessels 103 having 
their mouths 103a disposed on the opposite sides from each other are 
released at the release position B and placed into pockets 141A formed on 
the conveyor 141, the vessel 103 disposed in such pocket 141A will have 
its mouth 103a placed on the engaging member 142 (see FIG. 15(a)). 
Subsequently, as the vessel 103 is conveyed downstream while it is held in 
the pocket 141A, the mouth 103a will engage the engaging member 142 while 
the outer periphery in the rear region, as viewed in the direction of 
travel, is supported by the plate member 145, and since the outer 
periphery of the vessel 103 becomes engaged with the engaging member 144, 
the vessel will be gradually rotated to be erected (FIG. 15(b) to FIG. 
15(d)). 
It is to be noted that in the above description of the fourth embodiment, 
parts corresponding to those shown in the first embodiment are designated 
by like numerals as used before, to which 100 is added. Again, a similar 
functioning and effect are achieved as mentioned previously. 
Fifth Embodiment 
FIGS. 16 and 17 illustrate a fifth embodiment of the invention. In the 
fifth embodiment, located adjacent to one end of a first conveyor 202 is a 
second conveyor 202' which is disposed to extend in a direction 
perpendicular to the first conveyor, and a dishcarge conveyor 214 is 
disposed to be parallel with and alongside the second conveyor 202'. In 
the fifth embodiment, a vessel 203 is a flat vessel such as having an 
elliptical cross section, and such vessels 203 are supplied in random 
orientations onto the first conveyor 202 to be conveyed to the catch 
position A. 
In the fifth embodiment, a robot 213 is provided with a single vacuum pad 
232, and is constructed such that after it has caught a vessel 203 at the 
catch position A, when it releases the vessel 203 at a release position B, 
it delivers the vessel into each pocket 202a' formed on the second 
conveyor 202 with its mouth 203a oriented to the left, as viewed in FIG. 
16. 
A plurality of plate members 202b' are mounted on the vessel receiving 
surface of the second conveyor 202' at an equal pitch to define the 
individual pockets 202a', and a guide member 233 in the form of a rod is 
disposed over the second conveyor 202' so as to cross the path of 
conveyance of this conveyor. The discharge conveyor 214 is disposed 
adjacent to the guide member 233, and includes a pair of drop guides 234 
which are maintained at a given spacing from each other and which are 
chevron-shaped in section, formed by plate members, so that their insides 
opposing each other decline downwardly to define a valley therebetween. 
A vessel 203 which is delivered to the pocket 202a' on the second conveyor 
202 will be urged toward the pair of drop guides 234 as a result of the 
engagement of its mouth 203a with the guide member 233 as it is conveyed 
downstream on the conveyor, and is then guided by the pair of drop guides 
234 as it falls to pass therebetween to be placed on the discharge 
conveyor 214. As a result of the guiding action of the drop guides 234, 
the vessel 203 will be erected to its upright position on the discharge 
conveyor 214. Thus, in the fifth embodiment, the combination of the pocket 
202a' of the second conveyor 202', the guide member 233 and the drop 
guides 234 constitute together correction means 215 which erects the 
vessel 203. 
In the fifth embodiment, rotary encoders 217, 217' are mounted on the first 
and the second conveyors 202, 202', respectively, for detecting the speed 
of conveyance, which is input to a controller 212. In response to the 
speed of conveyance of each conveyor 202, 202' detected by the both rotary 
encoders 217, 217', the controller 212 causes the vacuum pad 232 of the 
robot 213 to follow the conveying operation of the both conveyors 202, 
202' when the pad 232 receives and delivers the vessel 203 at the 
positions A and B. 
In other respects, the arrangement is similar to that of the first 
embodiment. It is to be noted that the components appearing in the fifth 
embodiment and corresponding to those shown in the first embodiment are 
designated by like reference numerals as before, to which 200 is added. 
Again, if the size of the vessel 203 is changed, there is no need of 
remodelling components which constitute together the vessel aligning 
apparatus 201 according to the fifth embodiment, thus providing a high 
versatility as in the first embodiment. 
While the invention has been described above in connection with several 
embodiments thereof, it should be understood that a number of changes, 
modifications and substitutions therein will readily occur to one skilled 
in the art from the above disclosure without departing from the spirit and 
scope of the invention defined by the appended claims.