U.S. patent number 3,799,320 [Application Number 05/286,681] was granted by the patent office on 1974-03-26 for turn table device.
Invention is credited to Pieter Arnoldus V.D. Bilt.
United States Patent |
3,799,320 |
V.D. Bilt |
March 26, 1974 |
TURN TABLE DEVICE
Abstract
The present invention relates to a turn table device by means of
which objects, such as bundles of news papers, can be rotated about
a vertical axis over an angle of, e.g. 90.degree.. The turn table
has the form of a vertically movable and rotatable cross having its
wings below the plane of conveying means when retracted and above
said plane when in operation. The device has been provided with
switches and abutments to space the objects and to make sure that
only one object at a time can be brought above the cross of the
turn table device and that no feed or discharge can take place when
this is not desired by the presence of objects downstream. The turn
table device of the invention in particular is intended to be
installed between two strapping machines to cross-tie bundles of
news papers.
Inventors: |
V.D. Bilt; Pieter Arnoldus
(Bosch En Duin, NL) |
Family
ID: |
23099694 |
Appl.
No.: |
05/286,681 |
Filed: |
September 6, 1972 |
Current U.S.
Class: |
198/401; 100/7;
100/14; 198/414 |
Current CPC
Class: |
B65G
47/244 (20130101) |
Current International
Class: |
B65G
47/244 (20060101); B65G 47/24 (20060101); B65g
047/24 () |
Field of
Search: |
;198/33AB ;214/6P
;192/85C,33R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Blunk; Evon C.
Assistant Examiner: Watts; Douglas D.
Attorney, Agent or Firm: Young & Thompson
Claims
I claim:
1. Turn table device comprising a frame, a work table at the top of
said frame, conveying means defining the top plane of said work
table and adapted to convey an object from one end of the work
table toward the other end, said work table further comprising a
vertically movable cross stepwise rotatable about a vertical axis,
said cross in its lower retracted position having its wings below
the said top plane and in its upper operative position above said
top plane, drive means for the stepwise rotation of said cross,
said drive means being controlled by a switch having an actuating
lever extending above said top plane, said switch being mounted
upstream of said cross and being in a control circuit such that the
drive means are put into operation for lifting and rotating the
cross when the said switch is released by an object upon the work
table, said drive means comprising a friction disc rotatably
mounted on the frame about a vertical axis and adapted to be
continuously driven, a vertical shaft concentric with said disc,
the upper end of said shaft carrying the cross, whilst the lower
end carries a second friction disc having radially extending wings,
means for moving said shaft upwardly to bring the second friction
disc into engagement with the first friction disc and for moving
said shaft downwardly to disengage the said friction discs, a
further switch which in the raised position of the shaft can be
actuated by a said wing and when actuated controls the means for
moving said shaft to move downwardly, retractable abutment pins in
the work table located downstream of the cross and a still further
switch having an actuating lever extending above said top plane and
located downstream of said abutment pins, said circuit being such
that the abutment pins will extend above said top plane as soon as
an object completes its rotation but only if a preceding object is
depressing the actuating lever of the said further switch and will
retract below said plane when said still further switch is
released.
2. Device according to claim 1, characterized in that in front of
said further switch a downwardly extending plate has been pivotably
suspended within the frame, which plate lies in the path of the
wings when in their raised position and can actuate said further
switch and which in its free downwardly hanging position is out of
the vertical path of the adjacent wing which in its lower position
is prevented to rotate with the shaft by guide pins.
3. Device according to claim 1 combined with upstream mounted
separate supply conveyor means, characterized in that the drive
means of said separate supply conveyor means are connected to the
control circuit of the device such that said drive means cannot be
re-energized when said still further switch is depressed.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates to turn table devices which are
adapted to receive continuously fed objects, turn said objects
individually and one at a time about a vertical axis over a
predetermined angle and pass the turned objects on for further
processing. More particularly, this invention relates to a turn
table device which is adapted to be installed between two wire or
band strapping machines in line to cross-tie bundles of news papers
or magazines. Thus the device can successively receive a single
tied bundle of news papers or magazines from the first strapping
machine, turn the bundle 90.degree. about a vertical axis and feed
the turned bundle onto the second strapping machine which completes
the cross-tie operation by applying a second crosswise band or wire
around each turned bundle.
Accordingly, in the specification and claims to follow the present
invention will be disclosed with respect to a turn table device for
turning bundles of news papers or magazines positioned in line
between two band or wire strapping machines, but it should be
understood that the device according to the invention is not
limited thereto and can be employed or adapted for other uses as
well, such as for turning stacks of sheet material, bundles of
envelopes or forms, packages, containers or the like, whereby the
turn table device can be installed between machines or conveyors of
any suitable type or even form a part of a single conveyor or
machine.
Turn table devices of this type are known which operate in a
similar manner as the device according to the invention in that
they successively can receive objects to be turned from a supply
source such as a conveyor feeder belt or a processing machine, turn
said objects one by one 90.degree. about their vertical axis or
another vertical axis and feed the turned objects onto another
processing machine or a suitable discharge conveyor. However, the
embodiments of such known devices differ substantially from the
particular embodiment of the turn table device according to the
present invention. The essential difference is the fact that the
known devices comprise relatively complicated conveying means such
as push and pull mechanisms to convey the objects to be processed
onto and from a generally circular turn table, which means are
positioned externally of the work table containing the turn table,
whereas in the present invention the embodiment is such that the
turning and conveying means are suitably and completely arranged
inside the work table of the turn table device.
Such known devices suffer from various disadvantages, a principal
disadvantage being the complexity of the device due to the
particular arrangement of the conveying means, which in turn is a
main cause of other drawbacks, such as heavy weight, expensiveness,
complicated control systems, diminished surveyability, decreased
accessibility for maintenance and repair. Furthermore, the
complexity of the known devices and the particular arrangement of
the conveying and turning means substantially influence the
reliability, effectiveness and capacity of the devices. It has been
found that the transfer of objects or bundles onto and from the
turn table in the known devices is difficult to properly execute
due to bundle obstructing machine surfaces or inaccurate
functioning of the conveying means. Consequently the chance of
jamming or clogging is relatively high. In addition, it sometimes
causes a faulty turn angle of the objects or bundles which in turn
can lead to improper further processing. Furthermore, it often
damages the objects or bundles being handled and sometimes produces
relatively heavy wear of machine-parts involved. As the conveying
and turning machine parts wear, the reliability of the device
rapidly decreases as a result of changing dimensions which affect
the accuracy and smooth execution of the conveying and turning
operation. Generally the positioning of the handled objects or
bundles on the turn table is difficult to carry out accurately and
is coupled with several time-consuming movements of parts of the
conveying means, thereby substantially limiting the capacity of the
known devices. Another important disadvantage of known turn table
devices is that such devices normally cannot easily be adjusted to
permit handling of different sizes of news papers or other objects.
In addition, the thickness of the bundle or the height of other
objects to be handled often has to be limited due to the particular
external arrangement of the conveying means.
Accordingly, it is an object of the present invention to provide
improved turn table devices which have a novel and simple
arrangement of the conveying and turning means in the work table
whereby these problems are eliminated.
It is also an object of the present invention to provide turn table
devices in which wear of moving surfaces generally does not affect
the reliability and effectiveness of the device.
Another object of the present invention is to provide turn table
devices which can easily be adjusted in order to accomodate
different sizes of news papers or magazines or other objects.
A further object of the present invention is to provide turn table
devices in which simple stop means are provided in the work table
in order to effectively block the flow of bundles or other objects
when necessary.
Briefly, these objects are achieved by providing a turn table
device comprising a frame, a work table at the top of said frame,
conveying means defining the top plane of said work table and
adapted to convey an object from one end of the work table towards
the other end, said work table further comprising a vertically
movable cross stepwise rotatable about a vertical axis said cross
in its lower retracted position having its wings below the said top
plane and in its upper operative position above said top plane,
drive means being provided for the stepwise rotation of said cross,
said drive means being controlled by a switch having an actuating
lever extending above said top plane.
These and other objects, features and advantages of the present
invention will become apparent from a consideration of the
following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
In the course of this description, reference will be made to the
accompanying drawings in which:
FIG. 1 is a schematic perspective view of a machine line showing a
turn table device according to the present invention installed in
line between two wire or band strapping machines;
FIG. 2 is a detailed schematic perspective view of a preferred
embodiment of the turn table device according to the present
invention;
FIG. 3 is a detailed schematic perspective view of the entrance
portion of the turn table device of FIG. 2 showing the conveying
means drive arrangement;
FIG. 4 is a schematic side elevational view of some details of the
turn table device of FIG. 2;
FIG. 5 is a schematic side elevational view of another detail of
the turn table device of FIG. 2 and drawn to an enlarged scale;
FIG. 6 shows the pneumatic diagram; and
FIG. 7 shows the electrical circuit diagram of the turn table
device according to the present invention.
DETAILED DESCRIPTION OF THE DISCLOSED EMBODIMENT are
In the drawings which are shown schematically, certain parts which
are not important or which are generally known have been broken
away or omitted for the purpose of clarity and need not be further
described as will be readily understood by those skilled in the
art.
Referring now to the drawings in greater detail and, more
particularly first to FIG. 1, a turn table device 10 according to
the invention is shown installed in line between two wire or band
strapping machines 11 and 12 of a known type, for example such as
disclosed in U.S. Pat. No. 3,589,275 or No. 3,667,378 both in name
of Van de Bilt, which machine line is adapted to cross-tie bundles
of newspapers or magazines 13. Bundles of newspapers or magazines
13 to be strapped enter the machine line by means of, for example,
a conveyor 14 of any known type and are fed onto the work table of
the first strapping machine 11 which machine is adapted to apply a
wire or band 15 tightly around each bundle in a direction
transversely with respect to the conveying direction, the latter
being indicated by arrows A. After being strapped, the single tied
bundle 13 is then conveyed onto the work table of turn table device
10 which device is adapted to successively receive the bundle 13,
turn the bundle by means of a cross-shaped turn table 16,
90.degree. about its vertical axis and feed the turned bundle 13
onto the second strapping machine 12. Machine 12 in turn provides a
second wire or band 17 tightly and crosswise around each turned
bundle 13 also in the transverse direction in order to complete
cross-tieing of the bundles 13. After thus being cross-tied, the
bundles 13 are then conveyed onto, for example, a conveyor 18 of
any known type located in line downstream of machine 12 in order to
leave said machine line. Subsequently the bundles 13 can be
stacked, distributed or otherwise handled by any suitable known
means (not shown) as desired. In FIG. 1 the bundles 13 are shown in
subsequent stages of processing. The bundle conveying means of the
turn table device 10 are disposed in the work table of the device
10 are disposed in the work table of the device 10 and will be
described below in detail. The operation of the turn table device
10, the strapping machines 11 and 12, and the conveyors 14 and 18
is coordinated, as will be described below so that no piling up or
jamming can occur anywhere between the feed conveyor 14 and the
discharge conveyor 18 in order to ensure the orderly and
uninterrupted processing of the bundles 13 without clogging said
machine line. The strapping machines 11 and 12 are dimensioned to
permit processing of any size of newspaper or magazine in bundles
of any manageable thickness. In a preferred embodiment of the
invention the turn table device 10 can be adjusted in accordance
with the size of newspaper or magazine to be handled.
FIG. 2 shows a preferred embodiment of the turn table device 10
according to the present invention. The device 10 has a
conventional framework 19 constructed of structural members such as
plates, beams and sections. The work table of device 10 contains
turning means in the form of a cross-shaped turn table 16 as well
as conveying means, respectively for turning and conveying of the
bundles 13. The bundle conveying means consist of two longitudinal
parallel rows of each ten rollers 20, one row being located at the
left hand side of the work table and the other row at the right
hand side when seen in the conveying direction A. The rollers 20
are transversely positioned and rotatably mounted between
longitudinal beams 21 and 22, respectively 23 and 24 of frame 19,
the beams 22 and 23 being suitably spaced in the transverse
direction in order to accomodate various machine parts, among which
turn table 16, as will be described below. The rollers 20 are
continuously rotated in a direction indicated by arrows B by means
of a machine drive unit consisting of an electric motor 25 combined
with a reduction gear 26 located below the work table of device 10,
as shown in FIGS. 2 and 3. By engaging the bottom surface of the
bundles 13, the upper surface of rollers 20 can convey the bundles
13 over the work table of device 10 in the conveying direction A.
For that purpose all fixed machine parts are suitably located below
the horizontal plane tangent to the roller upper surfaces, as is
best seen in FIG. 2 and FIG. 4, in order to ensure unobstructed
conveying.
Referring more particularly to FIG. 3, the electric drive motor 25
and reduction gear 26 are mounted in the entrance portion of the
device 10, the entrance end of device 10 being indicated by 27 and
the exit end by 28, on a mounting plate 29, which is secured to
transverse plates 30 and 31 of frame 19. Electromotor 25 provides a
continuous driving force for the rollers 20 by means of a drive
shaft 32, the direction of rotation being indicated by arrow C, to
which a small drive pulley 33 and a larger drive pulley 34 are
fixed, the large drive pulley 34 driving a pulley 35, as shown in
FIG. 3 by means of a belt 35' which extends around pulleys 34 and
35. Pulley 35 is mounted on a rod 36 rotatably supported in a
support structure 37 which is located below the conveying rollers
20 in the entrance portion of machine 10. At its free ends, rod 36
carries drive rollers 38 respectively 39, which are rigidly secured
to it. Rollers 38 and 39 carry belts (not shown) adapted to drive
the rollers 20 by engaging the grooves 20' of said rollers 20 at
the underside, said belts running over intermediate and end discs
(not shown). The rollers 20 in each row are interconnected by the
friction drive of said belts so that all rollers in a row rotate
continuously in a direction of rotation indicated by arrows B in
order to convey bundles 13 in the direction A when necessary. When
bundles 13 have to wait, for reasons described below, while being
carried by the driven rollers 20, the relatively smooth outer
surfaces of the rollers 20 will permit slipping without damaging
the bundles.
The conveying means being completely described, the particular
arrangement and operation of the turning means and stop means for
the bundles 13 will now be disclosed with reference to FIGS. 2, 4
and 5. Besides rollers 20, the work table of machine 10 comprises,
when seen in the conveying direction A, between its entrance end 27
and its exit end 28, firstly switch means 40, secondly turn table
16, thirdly stop means in the form of abutment pins 41 and 42, and
finally another switch means 43. The turn table 16 is cross-shaped
to permit some of the rollers 20 to be positioned close to the
transverse portion of cross 16. Turn cross 16 can be raised
vertically, turned 90.degree. clockwise about its vertical axis and
returned to its initial sunk position in order to accomplish
turning of each bundle 13, so that each bundle 13 after being
strapped in one direction in the first strapping machine 11 can
subsequently be strapped in the other direction in the second
strapping machine 12 (vide FIG. 1). Turn table 16 in its inactive
sunk position in the work table, as shown in FIG. 2 and FIG. 4 in
solid outline, rests upon a supporting member 44 which is mounted
between longitudinal beams 22 and 23 at a little distance below the
top surfaces of said frame beams. Beams 22 and 23 are locally
recessed to accomodate the wings of cross 16. Turn table 16 in this
lowest rest position is out of engagement with any bundle 13
carried on the work table of device 10, the turn cross 16 being
completely positioned below the horizontal plane tangent to the
upper surface of the rollers 20 and having one wing positioned in
the longitudinal direction between beams 22 and 23 and the other
wing positioned in the transverse direction between some of the
rollers 20. From this lowest position, turn table 16 can be raised
vertically into an upper position, as shown in FIG. 4 in which the
upper position is indicated by dot and dash lines, above the
horizontal plane tangent to the roller upper surfaces as soon as a
bundle 13 to be turned has been conveyed by the rollers 20 into a
position just above the turn table 16. Turn cross 16 will thereby
lift this bundle 13 from the rollers 20 and will then turn together
with the supported bundle 13 clockwise 90.degree. about its
vertical axis and freely above the roller surfaces. Subsequently
turn table 16 will be returned to its retracted lowest position so
that now the initially longitudinally positioned wing of cross 16
will be located in the transverse direction between the
abovementioned pairs of rollers 20. The turned bundle 13 will
thereby be transferred onto the rollers 20 which will further
convey it onto the second strapping machine 12 (vide FIG. 1) unless
it is stopped by abutment pins 41 and 42 when necessary. When a
bundle 13 has arrived above cross 16 while cross 16 is situated in
its inactive lowest position, this bundle 13 will just have
released the first limit switch 40 by its trailing end, which
release controls the operation of turn table 16, as will be
described below. Consequently turn table 16 will successively be
raised vertically, stopped, turned 90.degree. and moved down again,
together with the supported bundle 13. When a preceeding bundle 13
depresses and so actuates the second limit switch 43, and turn
table 16 at the same time has just returned into its retracted
position, the normally retracted abutment pins 41 and 42 will be
operated and vertically raised from their retracted position in the
work table below the horizontal plane tangent to the roller upper
surfaces, a position shown in solid outline in FIG. 2, in order to
stop the bundle 13 which is just leaving turn table 16. The
abutment pins 41 and 42 will remain raised until switch 43 is
deactivated upon passing of the preceeding bundle 13. In this way
the flow of bundles 13 can be blocked when necessary in order to
create space between the bundles and prevent clogging or piling up
of the bundles. In this case the first strapping machine 11 (FIG.
1) at the same time is prevented of delivering a next bundle 13
onto the turn table device 10 by any known obstruction means, and
will not deliver a bundle 13 until the bundle 13 stopped against
abutment pins 41 and 42 is conveyed beyond these pins upon release
of switch 43 by the preceeding bundle 13 which release causes the
pins 41 and 42 to be retracted into their inactive lower
position.
The operation of the turn table 16 of the turn device 10 is
effected by a lift and turn mechanism which will now be disclosed
in detail with reference to FIGS. 2, 3, 4 and 5. The machine drive
unit comprising electromotor 25 and reduction gear 26 drives,
besides rollers 20, continuously a disc 45 which is rotatably
mounted at the bottom end of a fixed vertical tubular member 46.
Tube 46 is attached to the turn table supporting member 44 at its
upper end and is concentrically arranged around a vertical shaft 47
on top of which the turn table 16 is secured. The driven disc 45 is
provided with a friction clutch 48 mounted at its lower side. Shaft
47 is rotatable and vertically slidable within tube 46, and extends
downward beyond disc 45. A circular clutch plate 49 is mounted at
the bottom end of shaft 47 and is provided with a friction surface
on its upper side for engagement with clutch 48. Plate 49 at its
bottom side comprises four fixed wings 50, 51, 52 and 53, radially
projecting from the plate and spaced at 90.degree. with respect to
each other along its circumference. A pneumatic retraction cylinder
54 is with its blind end portion mounted to a bracket 55, the
bracket 55 being secured to a vertical support plate 56 which is
rigidly attached to beams 22 and 23 at its upper end and to base
plate 57 of frame 19 at its lower end. The piston rod 58 of
cylinder 54 is hingedly connected at 59 to a swivel arm 60 which is
pivotally mounted to a pivot rod 61 at 62. Pivot rod 61 is
supported by brackets 63 and 64 on base plate 31 of frame 19. Upon
actuation of cylinder 54, the piston rod 58 will be retracted and
thereby pivots arm 60 upward about pivot rod 61 and lifts the turn
table 16 by lifting the unit consisting of wing plate 49, shaft 47
and turn table 16, shaft 47 sliding within tube 46. The vertical
movement of said unit is guided by guide pins 65 and 66. Support
69, rigidly attached to a support block 70 which is mounted on a
support structure 71 connected to frame 19, carries a plate 67
secured to a hinge pin 68. This plate 67 by its excentric
connection to the pin 68 extends downwardly in an inclined
position, as shown in FIG. 5. Support 69 further carries a switch
76, 77 which can be actuated by plate 67. The turn table unit will
be lifted until friction plate 49 engages friction surface 48 of
the driven disc 45 which will cause plate 49 to be rotated in the
same direction thereby also turning turn table 16 clockwise about
its vertical axis above rollers 20. Disc 45 is driven by means of a
belt 72 extending around drive pulley 33 on shaft 32 of the machine
drive unit (25, 26), guide pulleys 73 and 74 rotatably mounted on
pulley support block 70 and disc 45, as shown in FIG. 2. The
direction of rotation of drive pulley 33 is indicated by arrow C
and that of disc 45 by arrow D. Upon rotation over nearly
90.degree. the turn table 16 being in its upper position as shown
in dot and dash lines in FIG. 4, one of the wings (50, 51, 52, 53)
of plate 49, i.e., wing 51 in FIG. 2 each time hits a plate 67
which plate then will act against a small roller 75 rotatably
mounted on the switch operating lever 76. Lever 76 is thereby
pivoted which actuates limit switch 77 mounted to the vertical
support 69. As is best seen in FIG. 5, lever 76 has a limited
stroke, the initial position of parts 67 and 75 being shown in
solid lines and the actuated position being shown in dot and dash
lines, and thus provides a stop for the engaging wing of plate 49
thereby limiting the rotation of turn table 16 to exactly
90.degree.. The depressed lever 76 trips switch 77 which controls
the vertical movement of turn table 16. The actuated switch 77
causes cylinder 54 to be provided with air in its blind end which
causes the arm 60 to be pivoted down again. This allows the unit
comprising turn table 16, shaft 47 and wing plate 49 to move down
by its own weight, shaft 47 sliding within tube 46, until turn
table 16 reaches its retracted position on supporting member 44.
Lever 76 is thereby released into its initial position, shown in
solid lines in FIG. 5, by the descending wing (51 in FIGS. 2 and 5)
the movement of the descending wing (indicated by arrow E) being
guided by the guide pins 65 and 66 on member 69 in order to
maintain the angular rotation of turn table 16 at exactly
90.degree. so that cross 16 is permitted to return into its initial
retracted starting position. When the turned bundle 13 has been
conveyed beyond pins 41 and 42, the turn table 16 is then ready to
receive and turn a next bundle 13. Wing 51 when lifted again, will
then move upward until clutch 49 engages clutch 48. Due to the fact
that plate 67 returned to its inclined free downwardly hanging
position the raised wing, e.g., 51 does not engage said plate 67
and will upon operation of the friction clutch 48, 49 pass below
roller 75.
The stop means in the work table of device 10, in the form of
simple abutment pins 41 and 42, are normally maintained in their
retracted position, as described above, by means of a pneumatic
cylinder 78. Cylinder 78 is with its blind end portion mounted to a
support 79 which is secured to transverse plate 80 of frame 19.
Plate 80 is provided with two openings 81 and 82 through which pins
41 and 42 respectively extend upward. Piston rod 83 of cylinder 78
is at 84 connected to a yoke 85 on which abutment pins 41 and 42
are mounted. Cylinder 78 normally keeps pins 41 and 42 in their
retracted inactive position, as shown in solid lines in FIG 2,
against the bias of tension springs 86 and 87 disposed between yoke
85, and beam 22 and beam 23 respectively. Guide rod 88 mounted at
the bottom side of yoke 85 extends downward through opening 89 in
transverse plate 90 of frame 19 to vertically guided the movement
of pins 41 and 42 and also functions to keep cylinder 78 in place
by carrying some of the load when the pins 41 and 42 have to stop a
bundle 13. Tension springs 86 and 87 will pull the pins 41 and 42
upward into their raised abutment position upon deactivation of
cylinder 78 by exhausting its blind end and will maintain them in
their blocking position as long as cylinder 78 remains
retracted.
Switch means 40 and 43 can be slidably adjusted in the longitudinal
direction along their supports 91 and 92 respectively, which
supports are fixed to frame 19, in order to be positioned as
necessary to permit device 10 to handle a particular size of
newspaper or magazine. The limit switched 40 and 43 have pivotable
levers 93 and 94 respectively, normally projecting vertically from
the work table beyond the horizontal plane tangent to the roller
upper surfaces. When a bundle 13 passes a switch lever, the lever
will be depressed into a substantial horizontal position and
released upon passing of the trailing end of the bundle 13 into its
initial vertical position. This depressing and release provides
control signals for the machine operation, as will be described
hereinafter.
It will be understood that the arrangement of the pneumatic and
electrical control systems of the present invention is decisive for
a correct functioning of device 10. Referring now to FIGS. 6 and 7
of the Drawings, the pneumatic and electrical systems will be
described in detail. As shown in FIG. 6, the pneumatic system
mainly comprises a pressure supply source (not shown) adapted to
continously supply air under pressure into the system through an
air entrance conduit 95 and a lubrication device 96 to lubricate
air entering the system, various air conduit means, the turn table
cylinder 54 (vide also FIG. 2), the abutment cylinder 78, and
solenoid operated air valves 98, 100 and 102, the solenoid of each
generally being indicated at 97, 99 and 101 respectively.
As shown in FIG. 7, the single phase control circuit power for the
electrical system is obtained from the upstream installed strapping
machine (machine 11 as shown in FIG. 1) by connections B and D. An
electrical obstruction circuit is provided (connections A and C) to
prevent the feeder belt drive motor of the upstream installed
strapping machine 11 from being restarted as long as feeding a new
bundle 13 to the turning device 10 is not desirable. The electric
drive motor 25 (vide also FIG. 2) is connected to the power source
(connections L1, L2 and L3) when starter relay 103 is energized by
the control circuit power of the downstream installed strapping
machine (machine 12 as shown in FIG. 1) (connections b and d). The
obstruction relay 104 (connections c and d) is energized by the
control circuit power of the downstream installed strapping machine
12 but only as long as the feeder system of said machine 12 is in
operation. The normally open contact of relay 104 is part of said
electrical obstruction circuit.
With reference to FIGS. 6 and 7, the operation which will be
readily understood by those skilled in the art is as follows:
As soon as a bundle 13 leaves the first strapping machine 11 and
moves onto the turn table device 10, switch 40 (vide also FIG. 2)
is tripped and the energized relay 105 closes the normally open
contacts. When the bundle 13 reaches the position of just above the
turn table 16, switch 40 is released by the trailing end of that
bundle, energizing solenoid 101 via switch 77 and the normally open
but now closed contact of relay 105 and switch 40, which causes
solenoid operated air valve 102 to be actuated. The actuated valve
102 provides air to the rod end of the turn table cylinder 54,
which moves the turn table 16 upward, causing the clutch 49 mounted
on the bottom end of the turn table shaft 47 to engage clutch 48 of
driven disc 45. When turned 90.degree., one of the four wings (50,
51, 52 and 53) mounted on the lower friction plate 49, hits the
switch operating plate 67 (as is best seen in FIG. 5). This plate
67 operates lever 76 which has a limited stroke so that it stops
the turn table 16 and trips switch 77, causing de-energization of
relay 105 and solenoid 101 of valve 102. Simultaneously, solenoid
99 of solenoid operated air valve 100 is energized through the now
closed contact of switch 77, permitting valve 100 to provide air to
the blind end of the turn table cylinder 54 which allows the turn
table 16 to move down. The switch lever 76 returns to its initial
position and the released switch 77 de-energizes solenoid 99 of
valve 100 which permits valve 100 to return to its initial
position. The turned bundle 13 is moved freely over the abutment
pins 41 and 42 because said pins are kept down in retracted
position by the abutment cylinder 78 which is pressurized on the
blind end via solenoid operated air valve 98. Solenoid 97 of valve
98 is energized via the normally closed contacts of relay 106. If
the last bundle 13 cannot enter the second strapping machine 12 for
one reason or the other, this bundle will be stopped just beyond
the abutment pins 41 and 42, keeping switch 43 depressed. The next
bundle 13 turns 90.degree. and during this period relay 106 is
energized through switch 43 and the normally open but not closed
contacts of relay 105. When the switch operating lever 76 is
actuated by one of the wings (50, 51, 52, 53) of plate 49, as
described above, and trips switch 77, relay 105 will be
de-energized and opens again the normally open contacts. Relay 106,
however, remains energized via switch 43 and the now closed contact
of relay 106. Valve 98, its solenoid 97 no longer being energized
because contact 105 as well as contact 106 are now open, exhausts
the blind end of the abutment cylinder 78. The abutment pins 41 and
42, pulled upward by the tension springs 86 and 87, will stop the
bundle 13. As soon as the trailing end of the obstructing bundle 13
releases switch 43, relay 106 will be de-energized and closes again
the normally closed contacts. Consequently, solenoid 97 of valve 98
is re-energized and permits valve 98 to supply air to the blind end
of the abutment cylinder 78, causing the abutment pins 41 and 42 to
be retracted, thus releasing the stopped bundle 13. The conveyor
drive motor of the upstream installed strapping machine 11 cannot
be started unless at least one of the three contacts 104, 106 and
43, and in any case contact 103 of the obstruction circuit
(connections A and C) are closed.
From a consideration of the foregoing disclosure, therefore, it
will be evident that all of the initially recited objects of the
present invention have been achieved.
Although the present invention has been described and illustrated
in connection with a preferred embodiment, it is to be understood
that modifications and variations may be resorted to without
departing from the scope of the invention, as those skilled in this
art will readily understand. For instance, it is quite possible to
employ conveyor belts or other conveying means in the work table of
device 10 instead of rollers 20. Abutment pins 41 and 42 might then
be centrally located between beams 22 and 23.
All such modifications and variations are considered to be within
the purview and scope of the present invention as defined by the
claims.
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