U.S. patent number 3,602,452 [Application Number 04/873,532] was granted by the patent office on 1971-08-31 for strap dispenser.
This patent grant is currently assigned to Signode Corporation. Invention is credited to Leo Peter Sauer.
United States Patent |
3,602,452 |
Sauer |
August 31, 1971 |
STRAP DISPENSER
Abstract
A dispenser for coiled strapping material having a reel assembly
rotatably mounted on a depending arm assembly, which is pivoted to
a supporting frame structure. An unwound length of strap is trained
about a guide on the arm assembly which causes the arm to pivot as
tension is applied to the strap. The frame structure includes two
spaced-apart frictional brake pads which react in varying degrees
on the rim of the reel assembly and control the rate of rotation of
the reel assembly as the reel is moved in relation to the frame in
response to the pivot action of the arm assembly.
Inventors: |
Sauer; Leo Peter (Glenview,
IL) |
Assignee: |
Signode Corporation
(N/A)
|
Family
ID: |
25361821 |
Appl.
No.: |
04/873,532 |
Filed: |
November 3, 1969 |
Current U.S.
Class: |
242/421.8;
242/156; 242/422.4 |
Current CPC
Class: |
B65H
23/08 (20130101) |
Current International
Class: |
B65H
23/08 (20060101); B65H 23/06 (20060101); B65h
025/22 (); B65h 059/38 () |
Field of
Search: |
;242/75.42,75.43,75.46,105,156,156.2,86.7,99 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Mautz; George F.
Assistant Examiner: Walters; Gregory A.
Claims
What is claimed is:
1. A dispensing mechanism for strap comprising the combination of a
frame, an arm pivotally mounted on the frame, a reel, a coil of
strap material supported on the reel, means on the arm spaced from
the arm pivot supporting the reel for free rotary movement, means
on the frame disposed adjacent the reel for frictionally engaging
the reel to brake its free rotational movement when strap is not
being unwound from the reel, strap guide means on the arm spaced
from the arm pivot and defining a reaction member about which an
unwound length of strap is trained, whereby a pull on the unwound
length of the strap will react on the strap guide means and cause
the arm to pivot and move the reel out of engagement with the brake
means to allow the reel to freely rotate and as the pull on the
unwound length of strap is decreased, the arm will pivot to bring
the reel into engagement with the brake means thereby stopping its
free rotational movement.
2. The combination set forth in claim 1 and including a second
brake means connected to the frame and disposed adjacent the reel
for frictionally engaging the reel to brake its rotation, the
second brake means being spaced from the first brake means, whereby
as the pull on the unwound length of strap is decreased and the arm
pivots toward the first brake means, the reel will contact the
second brake means and slow the free rotation thereof prior to
contact with the first brake means.
3. The combination set forth in claim 1 wherein the means on the
arm spaced from the arm pivot for supporting the reel for rotary
movement comprises a pair of spaced-apart aligned sockets, each
socket defined in an upper edge of the arm assembly and including
spaced-apart upwardly extending side surfaces and a bottom surface
extending between the side surfaces.
4. The combination set forth in claim 3 wherein each socket
includes an outward projecting boss extending from one of the side
surfaces and spaced above and partially overlaying the bottom
surface.
5. The combination set forth in claim 1 wherein the means on the
arm spaced from the arm pivot for supporting the reel for rotary
movement comprises a pair of spaced-apart aligned sockets defined
in upper edge surfaces of the arm assembly and said reel assembly
includes a shaft having an outwardly projecting end removably
received in said sockets.
6. A dispensing mechanism for strap, and the like, comprising the
combination of a frame, an arm pivotally mounted on the frame, a
reel, a coil of strap material supported on the reel, means on the
arm spaced from the arm pivot supporting the reel for rotary
movement, first means on the frame disposed adjacent the reel for
braking the rotary movement of the reel, stop means on the frame
engageable with the arm for locating the arm in a rest position and
for positioning the reel in engagement with the first brake means
when strap is not being unwound from the reel, strap guide means on
the arm defining a retraction member about which an unwound length
of strap is trained, the strap guide means being spaced from the
arm pivot, whereby the arm is pivoted away from the rest position
and the reel is moved away from the first braking means in response
to a pull on the unwound length of strap acting on the reaction
member, second means on the frame disposed adjacent the reel for
braking the reel when the reel is rotating at a rate faster than
the strap is being pulled from the reel, said arm being pivoted by
gravity toward a rest position to move said reel into engagement
with the second braking means and continuing decrease in the pull
in the strap will allow the arm to return to rest position, thereby
engaging the reel with the first braking means.
Description
This invention relates generally to means for dispensing strap
material for use in conjunction with tools that operate to tension
and secure straps about bundles, cartons, or the like. More
particularly, this invention concerns a strap-dispensing apparatus
in which the strap material may be easily withdrawn from a rotating
coil thereof, manually, or automatically, and the dispensing
apparatus provides frictional braking means to prevent overtravel,
or backlash, thereby eliminating the possibility of snarling and
entanglement of the unwound strap material.
In the past, it has been a common practice to support a rotatable
reel of coiled strapping material and to turn the reel manually, or
by power means, in order to feed the strap into tensioning and
securing tools. One example of this type of structure is found in
U.S. Pat. No. 3,061,235, granted to H. C. Lingle, on Oct. 30, l962,
and assigned to the assignee of the present invention. Prior
dispensers have been adequate for the purposes for which they were
designed, but certain operational deficiencies have been
encountered due to the development of more proficient strapping
tools. Increased capacity and efficiency of improved strapping
tools have required higher feeding rates of strap material and to
eliminate the need for frequent replenishing of the supply of
coiled material, dispensers have been required to handle larger
coils of strap material. Because of the increased size of coils of
strapping materials handled by the dispenser, there has been an
increase in weight of the coils, which has affected the ability to
start and stop and control the rotation of the reel assembly.
There has been a need for a dispenser mechanism which will respond
in accordance with the demand for strap material and which can stop
and start easily, as well as effectively control the acceleration
and deceleration of the rotating coil and reel assembly in
proportion to the demand for and the supply of the material. If a
rotating coil and reel assembly overtravels due to rotational
inertia and does not stop when the demand for strap material is
satisfied, an uncontrollable condition will result with a slack, or
untensioned length of strap material being unwound from the coil,
which will in turn become snarled and entangled. This condition
usually results in snarls and permanent kinks in the strap material
which will upset the operation of the strapping tool, as well as
cause losses of material and operating time devoted to untangling
and straightening out of the snarled strap.
Accordingly, the present invention has solved the foregoing
problems by providing a dispensing apparatus which will start, stop
and control the rate of rotation of the dispensing reel and the
feeding of the strap material therefrom in accordance with the
demands from the strapping tool operator. A pivoted, depending arm
assembly supports the reel of strap material and guides the unwound
strap as it is drawn therefrom. By such an arrangement, the arm
assembly reacts to the pull on the strap and responds in a direct
relation to the demand for the strap, as well as the weight of the
strap supply and thereby controls the rate of rotation of the reel.
Another advantage is found in a simple braking arrangement in which
frictional force applied to the reel is in proportion to the
tension in the strap, thereby coordinating the acceleration and
deceleration forces within the strap and reducing the shocks to
which the strap might be subjected.
The dispenser assembly is a relatively simple mechanism which
requires no springs, chains, or levers to apply the brake force to
the reel. This arrangement has the obvious advantage of lower
manufacturing costs, as well as eliminating maintenance
requirements for periodic adjustment. The arm assembly supports the
reel assembly by a simple arrangement which allows easy removal of
the reel therefrom to minimize the time required to replenish the
supply. Reel assemblies are interchangeable and thus the
replenishing of the supply merely amounts to the substitution of an
additional reel assembly with a full coil of material.
Other advantages and features will become apparent from the
following description taken in conjunction with the accompanying
drawings, in which:
FIG. 1 is a side elevational view of the strap-dispensing apparatus
with certain portions broken away;
FIG. 2 is a rear elevational view of the strap-dispensing apparatus
shown in Figure 1;
FIG. 3 is a top plan view of the strap-dispensing apparatus shown
in Figures 1 and 2; and
FIGS. 4, 5 and 6 are schematic side views of the strap-dispensing
apparatus showing the operating parts in various working positions
during the acceleration, deceleration, and braking phases of
operation.
The apparatus of the present invention provides a positive means of
controlling the rotation of a coil of strapping material after a
length of strap has been withdrawn from the coil, thus eliminating
any undesirable overtravel of coil-strapping material and
preventing a condition in which loose and uncontrolled lengths of
strapping material could become snarled and entangled.
The present invention includes a frame structure which supports a
pivoted arm assembly that holds a rotatably mounted reel of coil
material. The invention operates in response to a tug, or a pull,
on the strap material by the strapping tool operator. This pull
will tension the strap and react on the arm assembly, which will
pivot and lift the reel of a strap material from a rest position in
which the rim of the reel is in contact with a first and second
frictional brake means secured to the supporting frame. When this
occurs, the reel is allowed to rotate freely on its pivot axis and
strap material can unwind in response to the operator demand. The
weight of the arm and the reel of strap material resists the pull
of the operator, which results in strap tension. The strap tension
will increase as force is applied by the operator until the reel is
accelerated to a point that its speed is equal to the rate of
demand. As the reel rotates, the combined forces of demand, weight,
and tension will allow the arm assembly to pivot until a balanced
condition is reached. In this condition, the rim of the reel is in
engagement with at least one of the two frictional brakes and will
continue in this relationship until the demand has been satisfied.
At that time, the tension is relaxed and the arm is allowed to
return to a rest position. When the arm returns to its rest
position, both braking means are in contact with the rim of the
reel and thereby stop all unwinding action.
Referring particularly to Figures 1, 2, and 3, the dispenser
apparatus comprises generally a coil of strap material 10 supported
by and contained within a reel assembly 12 which is rotatably
mounted on a shaft assembly 14 and supported on a depending arm and
strap guide assembly 16. The arm and strap guide assembly 16 is
pivotally secured to the support frame assembly 18 and swings in
relation thereto as strap 20 is withdrawn from the coil 10.
The reel assembly 12 includes a pair of spaced-apart disks 22 and
24 having peripheral rim surfaces 26 and 28. An annular support 30
extending from disks 22 and 24 supports the coil of material 10
concentrically in relation to the shaft assembly 14.
The shaft assembly 14 is supported on the arm assembly 16 and
provides rotational axis for the reel assembly 12, and is utilized
to lock the reel assembly 12 by means of a conventional wingnut 32
engaged with suitable threads (not shown) on the periphery of shaft
14. Included in this securing arrangement are hubs 34.
The supporting frame assembly 16 comprises a pair of side frame
members 36 and 38, only one of which is shown in detail in FIG. 1.
Each of the side frame members 36 and 38 includes a horizontal base
portion 40, and upstanding leg portions 42 and 44. The side frame
members 36 and 38 are joined by transverse braces 46, 48, 50 and
52, which are suitably welded, or otherwise secured, to form a
rigid frame assembly. Brace members 50 and 52 also serve to support
blocks or pads of frictional material secured thereto which serve
as a first braking means 54 and a second braking means 56, as will
be hereinafter explained. Brace member 50 additionally serves to
support a block of resilient material 58 which serves as a bumper
for the arm assembly 16 when it returns to a rest position.
An idler roller 60 is rotatably mounted on a shaft 62 which is
secured in suitable aligned apertures in a pair of spaced-apart
brackets 64 that are fixed to the upstanding leg portions 42 of the
side frame members 36 and 38. The idler roller 60 can be adjusted
in one of two positions by placing the shafts 62 in an alternate
pair of spaced apart aligned apertures 66 in the brackets 64. This
adjustment arrangement is provided to allow for repositioning of
the idler roller 60, depending on the direction in which the strap
20 is withdrawn from the coil.
A pair of laterally extending, inwardly directed stop members 68
are fixed to horizontal braces 70, which are secured at the
respective ends to the upstanding leg portions 42 and 44 of the
side frame members 36 and 38. Located at the upper ends of the
upstanding leg portions 44 of each of the side frame members 36 and
38 are a pair of aligned bearing members 72 which are secured to
the side frame members 36 and 38 and which receive a pair of stub
shafts 74 that pivotally support the arm assembly 16 in relation to
the frame assembly 18. The arm assembly 16 comprises a pair of
spaced-apart, depending side members 80, only one of which is seen
in detail in FIG. 1. The identical side members 80 are joined by a
transverse member 82. The entire arm assembly 16 may be
manufactured in various ways, such as welded fabrication, or
casting, forging, or the like. An idler roller 84 is pivotally
mounted on the lower ends of the side members 80 by a transverse
shaft 86, which is received and secured in suitable spaced-apart
aligned apertures. A flat spring member which serves as a strap
snubber 88 is fixed to the transverse brace 82 by any suitable
means, such as screws 90. The object of this strap snubber 88 is to
maintain engagement of the strap 20 with the periphery of the
roller 84, particularly when there is no tension or pull on the
strap 20.
At the upper end of arm assembly 16, along the upper edge of the
side members 80, there are a pair of spaced-apart sockets or
notches 92 which receive the outer ends of the reel shaft assembly
14 and support the reel assembly 12 in its relation to the arm
assembly 16, the first and second braking means 54 and 56, and the
frame assembly 18.
Each notch or socket 92 is formed by a pair of upwardly extending
side surfaces 94 and 96, and a bottom surface 98. In the particular
embodiment shown, the bottom surface 98 also includes a parallel
wear pad 100. A boss, or outward projection, extends from the side
surface 96 and overlies the bottom surface 98 in each of the
notches 92. The object of this projection, or boss 102 is to
prevent accidental movement of the shaft assembly 14 out of the
notch 92 under certain operating conditions, particularly when
swinging the arm assembly 16 to an extreme position in the
direction shown in Figure 4. The stop 68 serves to limit the amount
of forward movement, or swinging of the arm 16 in that particular
direction, while the resilient bumper 58 serves to limit the
rearward swinging of the arm assembly 16 and determines the rest
position. Accordingly, the arm assembly is free to swing between
the rest position to the upper stop position.
In operation, the coil of strap material 10 is loaded in the reel
assembly 12 by placing it over the annular support 30 and between
the disk members 22 and 24. The shaft assembly 14 is positioned in
the reel assembly 12 and the nut 32 and hubs 34 secure the entire
assembly as a unit. The reel assembly 12 is positioned within the
frame assembly 18 between the frame side members 36 and 38. The
ends of the shaft assembly 14 are aligned with the socket 92 of the
side members 80 of the arm assembly 16
In this particular position, as shown in FIGS. 1 and 6 of the
drawings, the outer periphery, or rims 26 and 28 of the reel disk
members 22 and 24 are at rest and bear against the first brake
means 54 and the second brake means 56. The ends of the shaft
assembly 14 in this particular position are relatively free within
the notches or sockets 92. In other words, as seen in FIG. 1, the
periphery of shaft 14 is not in contact with the upper surface of
wear pad 100 of the sockets or notches 92. The entire weight of the
reel assembly and the coil of strap material bears against the
break pads 54 and 56. Furthermore, the arm assembly 16 is in its
rearmost position, or rest position, against the resilient bumper
58.
The strap material is threaded around the outer periphery of the
idler roller 84 between the strap snubber 90 and extends upwardly
and outwardly of the frame assembly 18 to the strap tool mechanism
(not shown). The snubber 90 pushes the strap 20 against the outer
surface or periphery of roller 84 to insure that it is in position
when the dispenser assembly is operated and minimizes any slack
that may occur due to the absence of tension, or pull, on the strap
20. The idler roll 60 serves to assist in guiding and orienting the
direction of the strap 20 between the idler roll 84 and the
strapping tool (not shown). The idler roll 60 may be adjusted to an
alternate position, as previously explained, depending on the
location of the strapping tool operator relative to the strap
dispenser.
Referring now to FIGS. 1, 4, 5, and 6, as the strapping tool
operator requires strap material, strap 20 is pulled from the
dispenser reel 12, which results in tension in the strap 20 and
when the force is sufficient, the assembly 16 moves away from the
resilient bumper 58, and the arm assembly 16 pivots around the
shaft 74. As the arm assembly 16 moves away from the resilient
bumper 58 and pivots around the shaft 74, the socket 92 embraces
the periphery of shaft ends 14, thereby lifting the entire reel
assembly 12 away from the first and second braking means 54 and 56.
This action allows the reel 12 to rotate freely on its pivot axis
established by shaft 14 and the strap 20 begins to unwind.
The rate of unwinding depends upon the amount of force or pull
applied to the strap 20 by the tool operator and the overall weight
of the coil of strap and reel assembly. The weight of the arm
assembly 16 added to the weight of the coil of strap material 10
and the reel assembly 12 resists the pull on the strap 20 and
increases the strap tension. As the tension develops in the strap
20, the reel rotation is accelerated to a speed equal to the demand
for strap by the tool operator. This condition is generally shown
in FIG. 4. As the speed of rotation of the reel assembly begins to
increase beyond the demand of the tool operator, the tension within
the strap 20 will diminish. When this condition occurs, the arm
assembly 16 begins to rotate rearwardly around its pivot 74 towards
the bumper 58. As the arm assembly 16 pivots rearwardly around its
pivot axis 74, the reel assembly will reach the condition shown in
FIG. 5 with the disk rims 26 and 28 in contact with the second
brake means 56. When the reel assembly 12 comes in contact with the
second brake means 56, the reel will be slowed down and subjected
to a frictional drag, which will increase the tension within the
strap and require additional pull on the part of the operator. This
condition will again accelerate the rate of revolution of the reel
in relation to the demand applied to it by the operator through the
pull in the strap 20.
At this point, it should be noted that the pressure against the
second brake pad 56 is determined by the friction and pressure of
the rotating reel rims 26 and 28 against the frictional surface of
the pad 56. This pressure is not only determined by the tension of
the strap and the weight of the coil, but additionally by the angle
of the bottom surface 98 of the socket 92 in relation to the
surface of the brake pad 56. As seen in FIG. 5, the bottom surface
98 of the notch 92 is nearly normal, or approximately 90 .degree.
to the angle of the surface of the brake pad 56. As the arm 16
rotates towards its rest position, the angle of the bottom 98 will
increase, allowing the shaft 14 to move forwardly within the socket
towards the upwardly extending surface 94 of the socket. This will
allow additional pressure to bear against the brake pad 56, thereby
slowing down the reel additionally.
When the tension within the strap increases due to additional pull
on the part of the operator, the arm will again move forwardly and
relieve the pressure on the brake surface 56 in contact with the
rim surfaces 26 and 28. This will allow a slight acceleration of
the speed of the unwinding of the reel 12 in accordance with the
demand placed on the dispenser assembly by the operator. This
alternative action of acceleration and deceleration will continue
as long as strap 20 is being pulled off the reel.
It will be seen that in this manner the strap will never get out of
control and the reel cannot overtravel because as soon as there is
a reduction in pull and a corresponding reduction in tension within
the strap, the arm assembly will move rearwardly, bringing the rim
surface in greater and greater contact with the second braking
means, or frictional pad 56. During this alternative acceleration
and deceleration action, there will be reached a balance point in
which the braking resistance of the reel rims 26 and 28 against the
brake pad 56 will develop just enough tension within the strap 20
to support the weight of the arm, the weight of the reel and coil
material, and will be in direct proportion with the desired speed
of rotation with the strap unwinding from the reel.
When the supply of strap has been satisfied and strap 20 is no
longer being pulled from the dispenser apparatus by the operator,
the arm 16 will be allowed to swing around its pivot point 74 to
the position shown in FIG. 1 and FIG. 6. In this condition, the
first braking pad or brake means 54 will be in contact with the
rims 26 and 28 of the reel disks 24 and 22, and the full weight of
the reel will rest upon the frictional surfaces of pads 56 and 54.
The reel rotation will be quickly stopped, and there will be no
overtravel, or uncontrolled unwinding of the strap material. When
the reel and arm assembly moves to the position shown in FIG. 6,
the arm assembly will contact resilient bumper 58 to cushion the
abrupt stopping of the arm assembly.
As previously mentioned, the force of the braking action depends on
the weight of the arm and the weight of the reel assembly added to
the weight of the coil material. While the weight of the arm and
the weight of the reel assembly is constant, the weight of the coil
material varies as the supply of material is depleted. In other
words, when a new and heavy coil of material 10 is in the
dispenser, a greater pull and corresponding greater tension is
required to operate the entire mechanism. Correspondingly, a
greater braking force is required to stop the rotation of the coil,
because the entire added weight bears on the frictional surfaces.
When partially used C coils, or lighter coils, of material 10 are
utilized, decreasing amounts of force are required to brake and
stop the rotation of the coils. By this arrangement, it will be
seen that the braking force needed to stop the rotation of the
entire assembly is in direct proportion to the weight of the entire
assembly, and, therefore, large braking forces are not applied to
lighter coils of material, thereby reducing the internal shock and
tension. It will also be noted that the braking blocks or pads 54
and 56 are positioned in spaced-apart positions around the
circumference of the reel to give a uniform braking force applied
at different points on the rims 26 and 28. Their relative positions
are also allowed for equalized wear on the braking pads.
As previously explained, this dispenser apparatus is extremely
simple because it responds to operator demand and requires no
chains, blocks, levers, or other types of mechanisms to apply the
required brake force to control or coordinate the acceleration or
deceleration of the rate of rotation as the material is drawn from
the coil 10.
Thus, it will be seen from the foregoing that the present invention
provides an effective, efficient, manually operated dispenser
apparatus for strap material which responds to the demand for
additional strap and adjusts its unwinding action to the tension in
the strap to insure continuous control of the amount of material
dispensed therefrom. No slack, or uncontrolled lengths of material
can result because of the positive elimination of overtravel which
can be caused by rotational inertia. As soon as there is no pull or
tension within the strap, there is a positive braking action due to
the movement of the arm to its rest position.
Furthermore, the payout, or normal direction of material being
dispensed, can be altered without substantial physical effort or
the repositioning of the dispenser assembly in relation to the
operator and the strapping tool. The reloading of the dispenser and
the positioning of the reel within the entire assembly is
simplified and the utilization of interchangeable reel assemblies
eliminates the complication of additional mechanisms which can add
to the cost of the entire dispenser unit.
While there has been shown and described the preferred embodiment
of the invention, it will be apparent that the numerous
modifications and variations can be made without departing from the
underlying principles of the invention. Therefore, it is desired by
the following claims to include within the scope of this invention
all such variations and modifications by which the results of the
invention can be obtained through the use of substantially the
same, or equivalent means.
* * * * *