U.S. patent number 3,900,915 [Application Number 05/491,021] was granted by the patent office on 1975-08-26 for rotary coiled broom.
This patent grant is currently assigned to FMC Corporation. Invention is credited to Richard B. Rosseau.
United States Patent |
3,900,915 |
Rosseau |
August 26, 1975 |
Rotary coiled broom
Abstract
A street sweeping broom which is comprised of a rotary helical
brush strip tightly secured about a rigid cylindrical core. The
brush strip is of generally conventional construction and includes
a plurality of reversely bent bristles with the bights thereof
being maintained within a channel member by an anchoring wire and
by the crimping of the channel member at spaced locations along the
length thereof. Each of the ends of the helical brush strip is
secured to a guide member which also supports the coil directly
adjacent to the end of the brush strip. A ring having a plurality
of circumferentially spaced slots is secured to each end of the
core, and the guide members are attached to the rings by means of
an inclined, inwardly projecting tang which allows movement of the
guide member in only one rotational direction upon the ring. Thus,
ratchet-type mechanisms are provided to secure each end of the
brush strip to the core which mechanisms act to automatically take
up any slack in the brush strip during the usage thereof in order
to maintain it in tight engagement with the core.
Inventors: |
Rosseau; Richard B. (Claremont,
CA) |
Assignee: |
FMC Corporation (San Jose,
CA)
|
Family
ID: |
23950474 |
Appl.
No.: |
05/491,021 |
Filed: |
July 23, 1974 |
Current U.S.
Class: |
15/182;
188/65.1 |
Current CPC
Class: |
A46B
13/006 (20130101) |
Current International
Class: |
A46B
13/00 (20060101); A46b 007/10 () |
Field of
Search: |
;15/179,181,182,198,2DO
;29/127 ;188/196,65.1 ;242/107.2 ;300/21 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Feldman; Peter
Attorney, Agent or Firm: Kelly; R. S. Tripp; C. E.
Claims
I claim:
1. A rotary broom comprising a generally cylindrical core, a
helical brush strip wound about said core, a ring member secured to
one end of said core, said ring member having a series of stops
spaced circumferentially thereabout, and automatic tightening means
provided at the end of said brush strip adjacent to said ring
member for engagement with said stops on said ring member, said
tightening means and said stops being configured and oriented so as
to permit endless relative rotary movement therebetween in one
direction and to prevent relative rotary movement in the opposite
direction when said tightening means is in engagement with one of
said stops.
2. A rotary broom according to claim 1 wherein each end of said
broom is provided with one of said ring members and wherein each
end of said brush strip is provided with said automatic tightening
means.
3. A rotary broom according claim 1 wherein said automatic
tightening means comprises a guide member secured to said brush
strip and having a projecting tang arranged to engage said stops on
the associated ring member.
4. A rotary broom according to claim 3 wherein said ring member is
provided with a track extending circumferentially about the
periphery of said ring member and said guide member is provided
with means for riding upon said track of the ring member.
5. A rotary broom according to claim 1 wherein said tightening
means includes means for slidably supporting said brush strip at a
position spaced one coil from said end of the strip in order to
maintain said tightening means in engagement with said ring member
and at least one coil of such brush strip at said end of said
core.
6. A rotary broom according to claim 4 including a second guide
member secured to said brush strip at a position spaced
approximately one half coil from said end of the strip, said second
guide member being arranged to be received upon said track of said
ring member.
7. A rotary broom comprising a generally cylindrical core; a
helical brush strip wound about said core; and automatic take-up
means for maintaining said brush strip in tight engagement with
said core including a ring member secured to one end of said core,
said ring member having a series of recesses spaced
circumferentially thereabout, and a guide member clamped to the end
of said brush strip adjacent to said ring member, said guide member
having a projecting tang and being arranged to slide upon said ring
member with said tang being received in said recesses, the
interengagement of said tang and said recesses permitting said
guide member to rotate about said ring member in one direction but
preventing relative rotational movement therebetween in the
opposite direction whereby any slack which accumulates in said
brush strip will be removed by said automatic take-up means.
8. A rotary broom according to claim 7 wherein said ring member is
provided with a radially outwardly extending flange, said guide
member having a recessed portion arranged to be received upon said
flange of the ring member.
9. A rotary broom according to claim 7 wherein said guide member is
provided with means for slidably supporting said brush strip at a
position spaced one coil from said end of the strip in order to
maintain said guide member in slidable engagement with said ring
member and at least one complete coil of said brush strip at said
end of said core.
10. A rotary broom according to claim 7 including a second guide
member secured to said brush strip at a position spaced
approximately one half coil from said end of the strip, said second
guide member being arranged to slidably engage said ring
member.
11. A rotary broom according to claim 7 wherein said guide member
comprises a generally U-shaped member with the arms thereof
extending radially outwardly therefrom to receive said end of the
brush strip and bent being bent over said brush strip to securely
clamp the strip to the guide member, said tang projecting from the
undersurface of said guide member, said guide member further
including a laterally projecting ear arranged for sliding
engagement with said ring member.
12. A helical brush strip for attachment to a generally cylindrical
core of a rotary sweeper, said brush strip having a guide member
securely attached to one end thereof, a ring member slidably
attached to said guide member, said ring member being provided with
a series of uniformly spaced stops extending circumferentially
thereabout, means for securing said ring member to one end of said
core, said guide member including means arranged to engage said
stops on said ring member so as to permit endless relative movement
of said guide member upon said ring member in one rotary direction
but preventing relative movement therebetween in the opposite
rotary direction.
13. A helical brush strip according to claim 12 wherein each end
thereof has attached thereto one of said guide members and one of
said ring members.
14. A helical brush strip according to claim 12 wherein said guide
member is provided with a laterally projecting arm slidably engaged
with said brush strip at a position spaced one coil from said end
of the strip.
15. A helical brush strip according to claim 14 including a second
guide member secured to said strip at a position spaced
approximately one half coil from said end of the strip, said second
guide member having means for slidably engaging said ring
member.
16. In a rotary broom which includes a generally cylindrical core,
a helical brush strip wound about said core, means securing each
end of said brush strip to one of the ends of said core, and
automatic take-up means provided at at least one end of said core
for permitting take-up of any slack which accumulates in said brush
strip so that said brush strip will be maintained in tight
engagement with said core, the improvement wherein said automatic
take-up means comprises a ring member attached to said core at said
one end thereof, said ring member being provided with a series of
stops extending circumferentially thereabout, and a guide member
secured to one end of the brush strip for riding engagement with
said ring member, said guide member including means arranged to
engage said stops on said ring member so as to permit endless
relative movement of said guide member upon said ring member in one
rotary direction but preventing relative rotary movement
therebetween in the opposite rotary direction.
17. In a rotary broom according to claim 16 wherein each end of
said core is provided with said automatic take-up means.
18. In a rotary broom according to claim 16 wherein said guide
member is provided with a laterally extending arm slidably engaged
with and underlying said brush strip at a position spaced one coil
from said end of the strip.
19. A rotary broom comprising a generally cylindrical core, a
helical brush strip wound about said core, a ring member at one end
of said core, said ring member having a series of stops spaced
circumferentially thereabout, means for securing said ring member
to one of said core or said brush strip at the end thereof, and
automatic tightening means secured to the other of said core or
said brush strip for engagement with said stops on said ring
member, said stops and said tightening means being configured and
oriented so as to permit endless relative rotary movement
therebetween in one direction and to prevent relative rotary
movement in the opposite direction when said tightening means is in
engagement with one of said stops.
20. A slack take-up device for maintaining a helically coiled brush
strip in tight engagement with a generally cylindrical core, said
take-up device being mounted at one end of said core and said brush
strip, said take-up device comprising means for receiving and
clamping the end of said brush strip, and guide means extending
laterally from said last named means for slidably receiving said
brush strip at a position spaced one coil length from said end of
the strip whereby the end coil of said brush strip will always be
maintained in a fixed position with respect to said end of said
core.
21. A slack take-up device according to claim 20 wherein said guide
means comprises a flange which is arranged to underlie said brush
strip.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to rotary power brushes of the
street sweeping broom type, and more particularly, it pertains to
the means whereby a helically coiled brush strip can be maintained
in a tight condition upon the cylindrical surface of a broom core
member under full load conditions.
2. Description of the Prior Art
A typical construction for a rotary power brush, such as might be
used on street sweepers for example, comprises a generally
cylindrical core member about which a helical brush strip is
tightly wrapped. The brush strip includes a channel having a
tightly bunched, continuous series of reversely bent bristles
secured therein. The bristles are arranged to be secured within the
channel at their bight portions by means of an anchoring wire or
cable which extends the full length of the brush strip. In
operations such as street sweeping where the bristles wear quite
rapidly, the frequent changing of the brush strip becomes
necessary, and it is highly desirable that this operation be
capable of being performed in the field by relatively unskilled
personnel and not require complex and costly winding and tightening
equipment such as would be found only at a brush making
factory.
In one rotary brush construction of the aforedescribed type that is
widely used in the street sweeper industry and is shown in prior
U.S. Pat. No. 3,193,866 to Jones, one end of the brush strip is
fastened to the core by means of a slack accumulator device which
comprises a flexible cable attached to the end of the brush strip
and to the end face of the core so as to allow the brush strip to
rotate in one direction if slack develops along the length thereof
but preventing it from rotating in the opposite direction wherein
it would unwind from the core. When slack does develop in the brush
strip, the attachment of the aforementioned cable to the end face
of the core can be loosened, and the brush strip can be pulled
tighter about the core to remove such slack before reclamping the
cable to the core. Thus, by means of periodic manual take-up of the
slack in the brush strip, the brush strip can be maintained in a
fully tightened condition on the core so as to prevent damage to
the strip such as might occur if the end of the strip were
permitted to move freely on the core and strike its retaining
mechanism.
In the aforementioned prior art rotary coiled brush construction as
shown in U.S. Pat. No. 3,193,866, it was found to be necessary to
provide a fixed helical track upon the surface of the core for
receiving the coiled brush strip in order to maintain the coils of
the brush strip in the proper spaced relationship in order to
achieve a good brushing action with the broom. If the track were
not provided, any slackness which developed in the brush strip
might result in a spreading of certain adjacent coils which would
leave an undesirable streak in the brushed strip of road surface or
pavement.
An attempt to improve this basic rotary coiled brush construction
is disclosed in the recently issued U.S. Pat. No. 3,750,225 to
Gould et al. The rotary sweeping brush structure shown in this
patent also includes a helical brush strip which is arranged to be
rigidly secured about a cylindrical core element. However, no
channel means are provided upon the surface of the core element for
holding the brush strip coils in place. Instead, one or both ends
of the brush strip are provided with one-way clutch devices which
provide for an automatic positive take-up of any slack in the brush
strip as soon as it occurs. Thus, the need for the channel is
allegedly obviated since the automatic take-up provided by the
brush strip mounting means will maintain the brush strip in tight
engagement with the core at all times.
The street sweeping brush disclosed in the aforementioned U.S. Pat.
No. 3,750,225 has some disadvantages, however, which reduce its
effectiveness. For example, as pointed out in the patent, the brush
strip must be tightened by hand about the core element before it
can be put into use upon a street sweeping vehicle. One of the main
reasons for this requirement of pre-tightening is that the ends of
the brush strip become unsupported after any slackness is taken up
during the usage of the brush, and these free ends of the strip
cannot be permitted to become too long. Slack accumulator devices
are mounted upon the ends of the Gould et al core, and the ends of
the brush strip are provided with extensions (grooved or threaded
in actual practice) which are adapted to move through such slack
accumulator devices in one direction while being restrained from
movement in the opposite direction. As the brush strip is tightened
about the core the extension at the end thereof moves past the
slack accumulator device and extends freely adjacent to the end of
the core. If this free end becomes long enough, it can become
entangled in the dirt shoes or side deflectors adjacent to the end
of the core which could cause the brush strip to break unless a
special guard plate is provided to prevent this from occurring.
Also, there is a practical limit to the amount of take-up which can
be provided by the device shown in the Gould et al patent because
of the limited length of the brush strip extensions. Thus, initial
tightening of the brush strip is required before the slack
accumulator element is attached to the core so that the slack
accumulator can be attached to the very end of the brush strip
extension. Additional slack accumulation (under sweeper load
conditions) will be limited to but a fraction of the
circumferential length of one coil of the brush strip.
Another significant disadvantage of the street sweeping brush
disclosed in prior U.S. Pat. No. 3,750,225 is that no means are
provided for aligning the brush strip extension with the passage
through the slack accumulator device. If the brush strip extension
is initially misaligned or becomes misaligned due to shifting of
the end coil of the brush strip, the extension can bind in the
slack accumulator device and the slack accumulator device will fail
to function in its intended manner.
Another related disadvantage of the street sweeping brush shown in
the aforementioned prior U.S. Pat. No. 3,750,225 is that the
self-tightening feature will not prevent the brush strip coils from
spreading at the ends of the core where it is particularly
essential that the brush sweep cleanly. In order to prevent this
problem, means must be provided (not shown in the patent) for
maintaining a fixed spacing of the end coils of the broom so that
they will not shift axially on the core during the automatic
tightening of the brush strip. This means (which takes the form of
a clip removably secured to the core) also serves to align the last
coil of the brush strip with the slack accumulator device so that
the brush strip extension will feed freely therethrough without
binding. This clip must be removed before the brush strip can be
replaced on the core, and such removal has proven to be both a
difficult and a disagreeable job.
Another solution to the problem of providing a continuous positive
take-up means on the end of a helically coiled brush strip for
maintaining the brush strip in tight engagement with a cylindrical
core element is shown in U.S. Pat. No. 1,198,407 to Beckett. The
brush strip shown in this patent is attached to the core element by
means of a tension spring which may contract to take up slack
developed in the brush strip during the usage of the brush. The
spring in combination with the friction developed by the brush
strip coils prevent rotary movement of the brush strip in the
unwinding direction after the slack has been taken up.
SUMMARY OF THE INVENTION
The apparatus of the present invention comprises a rotary sweeper
broom structure which, like the broom structure shown in prior U.S.
Pat. No. 3,750,225, is provided with means for allowing an
automatic continuous take-up of the slack which inherently develops
in brush strip coils that are helically wrapped upon an underlying,
generally cylindrical core element. However, such continuous
take-up of the slack is arranged to be truly unlimited, and, in
fact, no hand tightening of any sort is required when the brush
strip is initially placed on the core element prior to the use of
the brush under load conditions, i.e., in a street sweeping
situation. That is to say, the coiled brush strip can be merely
slipped into place loosely over the core and attached loosely at
its ends to the ends of the core, and then the assembled broom can
be placed directly upon the powered street sweeper ready for use.
Rotation of the brush in place and under load then provides the
proper tightening of the brush strip coils. Like the brush of the
aforementioned U.S. Pat. No. 3,750,225, no helical track means is
generally required to keep the brush strip coils in the desired
uniformly spaced relationship.
The brush strip is arranged to be held in place on the core by at
least one ring member which is attached directly to the core at one
end thereof. This ring member includes a series of spaced stops or
recesses which extend circumferentially about the entire
cylindrical surface of the ring member. A guide member is securely
attached to the end of the brush strip adjacent to the ring member
and is arranged to ride upon the surface of the ring member as the
slack is removed from the brush strip. The guide member is provided
with means that successively engages the spaced stops on the face
of the ring member so as to permit relative rotational movement
therebetween in one direction but preventing such relative
rotational movement in the opposite direction. Thus, the end of the
brush strip can rotate endlessly about the ring, and there is no
practical or theoretical limit to the amount of slack take-up which
can be obtained. In the preferred form of the invention the guide
member is provided with means for slidably securing the brush strip
coil at a position spaced one coil length from the end of the
strip; this serves both to assure that the guide member will always
be properly aligned with the ring member so that binding or jamming
will not occur and to assure that the end coils of the brush strip
will be properly positioned at the end of the core.
The present invention possesses several distinct advantages over
the prior art rotary coiled brushes, particularly the device shown
in the aforementioned prior U.S. Pat. No. 3,750,225. First, as
mentioned hereinbefore, there is an unlimited amount of take-up
which can be achieved, and this permits the brush to be installed
with no pre-tightening of any kind being required. Also, in the
preferred embodiment of the invention, the guide member is slidably
attached to the brush strip one coil length from the end of the
strip so that the end two coils of the brush strip are maintained
in the proper closely spaced position close to the edge of the core
where full and effective sweeping is essential. The guide member in
the present invention will always be aligned with the ring member
whereby binding or jamming will not take place so as to prevent the
desired slack take-up movement from occurring. Another important
advantage of the rotary brush structure of the present invention is
that even after full slack take-up there is no free unsuported end
of the brush strip which might become entangled in the dirt shoes
or other mechanisms at the sides of the rotary broom structure.
The novel slack accumulating device of the present invention
thereby comprises the aforementioned ring member and guide member,
and such slack accumulating device may be provided at each end of
the core if the brush strip is subject to loading in either rotary
direction. Also, although it is preferred to attach the ring member
to the core and the guide member to the end of the brush strip, it
is possible to reverse this arrangement, i.e., attach the ring
member to the end of the brush strip and the guide member to the
end of the core, and still obtain the major advantages of the
present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of one end of a rotary coiled broom
which embodies the present invention with the coils of the brush
strip thereof being broken apart and separated from the core for
the purposes of illustration.
FIG. 2 is a fragmentary longitudinal section of the end of the
rotary coiled broom shown in FIG. 1.
FIG. 3 is a reduced section taken along the line 3--3 of FIG. 2
with the brush strip being removed from the guide member to which
it is attached for the purpose of clarity.
FIG. 4 is an enlarged section taken on the line 4--4 of FIG. 3 and
illustrating the ratchet-type connection of the guide member with
the underlying ring member.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIGS. 1 and 2, the rotary broom of the present
invention will be seen to comprise a generally cylindrical core 10
about which is wrapped a helical brush strip 12, the brush strip
extending the full length of the core in rather closely spaced
coils (as is conventional). An axle 13 is arranged to support the
core upon a street sweeping machine (not shown) in the conventional
manner. The brush strip, best shown in detail in FIG. 2, is
entirely conventional in construction and comprises a coiled
metallic supporting channel 14 within which is received a plurality
of reversely bent and closely bunched bristles 16 that extend
throughout the length of the brush strip. Each of the bristles is
secured at the bight thereof within the supporting channel 14 by
means of an anchoring wire 18 which, in the described embodiment of
the invention, is a twisted pair anchoring wire as disclosed in
prior U.S. Pat. No. 3,137,021. The bristles are additionally
retained in the channel by intermittently spaced crimped portions
19 (FIG. 1) spaced along the outer side edges of the channel
14.
The improvement representing the present invention basically
comprises the provision of means whereby at least one end of the
brush strip 12 is secured to the end of the core 10 so that
continuous positive accumulation of slack within the brush strip is
obtained. For this purpose, a cylindrical ring member 24 is loosely
assembled about the end surface of the core. This ring member
comprises a relatively large cylindrical flange portion 26 and a
relatively short cylindrical flange portion 27 which flange
portions are separated by a radially outwardly extending track
portion 28. The short flange portion 27 is positioned directly
adjacent to the end of the core and is provided with a series of
apertures 30 spaced about its circumference. Selected ones of the
apertures 30 are arranged to receive cotter pins 32 (as shown in
FIG. 1) in order to permit the attachment of the ring member to the
core. The large flange portion 26 of the ring member includes a
continuous series of uniformly spaced slots 34 which extend about
the entire cylindrical surface of the ring member.
The end of the brush strip 12 is arranged to be securely attached
to a clip or guide member 40 that is arranged to ride upon the
track portion 28 of the ring member 24 and is provided with means
whereby it is permitted to move in only one rotary direction upon
the surface of the ring member. This guide member, as best shown in
FIGS. 2 and 3 of the drawings, comprises a clip which has a
generally U-shaped body portion 42 arranged to receive the end of
the brush strip. The side walls of the body portion 42 of the guide
member are provided by a plurality of tabs 44 the upper ends of
which are bent transversely (as shown in FIG. 1) into closely
spaced adjacent relationship to securely lock the guide member
about the channel 14 of the brush strip and within the radially
extending bristles 16. A pair of reversely bent ears 46 extend
laterally outwardly from the body portion 42 of the guide member
and are adapted to be slidably received upon the track portion 28
of the ring member so that the guide member can freely slide about
the circumference of the ring member. A pair of flanges 48 at the
ends of the guide member extend laterally in the opposite direction
from that of the ears 46 and, as shown in FIG. 2 of the drawings,
underlie and serve to slidably support the brush strip at a
position spaced one coil length from the end of the strip. This
arrangement serves to properly maintain the end coils of the brush
strip close to the end of the core where they are needed. It should
be noted that the end portions of flanges 48 are bent so as to
extend radially outwardly and thus serve to maintain the coils of
the brush strip on the guide member. It will also be recognized
that the flanges 48 may extend along the core 10 for a distance
sufficient to support several coils of the brush strip if it is
desired to bunch the coils at the end of the core.
A particularly significant feature of the guide member 40 is that
the body portion 42 thereof includes a radially inwardly struck
tang 50 which extends rearwardly to the direction of travel of the
guide member and at an inclined angle thereto. This tang is
arranged to successively become engaged in the spaced slots 34 of
the ring member as the guide member is slid about the circumference
of the ring. The configuration of the tang is such that it will
pass over the slots when the guide member and the brush strip held
thereby are moved in one rotary direction (indicated by the arrow
in FIG. 3 of the drawings) but it will prevent any movement of the
guide member (and hence the brush strip) in the opposite direction
due to the engagement of its flat radially extending face 50a with
the trailing side edge of a slot - the trailing side edges of the
slots thereby serving as stops for the guide member. This locking
engagement of the tang with the ring member is specifically shown
in FIG. 4 of the drawings.
In order to further insure that the end coil of the brush strip
will be maintained in the proper relationship with respect to the
adjacent end of the supporting core, a second guide member or clip
60 (FIGS. 1 and 2) is secured to the brush strip at a position
spaced 180.degree., or one-half a coil length, from the end of the
strip. This second clip 60 comprises a generally U-shaped member
one side wall of which is formed by a tab 62 that is bent
transversely at the upper edge so as to overlie the channel 14 of
the brush strip and lock the brush strip thereto. The guide member
60 also includes a pair of laterally extending reversely bent ears
64 adjacent to the tab 62 for permitting the guide member 60 to
ride upon the track portion 28 of the ring member in the same
manner as that of the first guide member 40. It will be recognized
that if the guide member 40 is provided with flanges 48 which are
lengthened so as to support several coils of the brush strip, then
the second clip 60 must be widened accordingly.
The aforedescribed means for securing a brush strip about a core of
a rotary sweeper broom may be utilized on virtually any
conventional coiled brush strip-core construction. The guide member
40 is attached to the end coils of the brush strip as shown and is
merely placed upon the radially extending track portion 28 of the
ring member. The operator who is to do the actual changing of the
brush strip will therefore be provided with a replacement brush
strip which has attached thereto (on at least one end thereof) a
guide member and a ring member in assembled relationship. To mount
the brush strip upon the core it is then necessary to merely attach
the ring member 24 to the end of the core with the cotter pins 32
as shown. As the brush strip tightens upon the core when the brush
is subjected to loading (i.e., brushing) forces, the pull on that
portion of the brush strip which is engaged by the supporting
flanges 48 of the guide member will force the guide member
downwardly upon the ring member. Thus, the end of the brush strip
which overlies the projecting tang 50 will always be in secure
engagement with the ring member, and the guide member will always
be aligned properly with the ring member to prevent binding
therebetween. When it is desired to remove the brush strip for
replacement, the ring member is merely removed from the end of the
core by loosening the cotter pins 32, and a similar attachment
means or fixed connection at the other end of the core is also
removed. Then, the brush strip is allowed to unwind slightly so
that it becomes loose enough on the core so as to permit the entire
brush strip assembly to be slid axially from the core.
While the disclosed embodiment of the invention shows only one end
of the brush strip as being attached to the core with the slack
take-up means of the present invention, it will be understood that
both ends of the brush strip can be attached with a similar device,
and such method of attachment would be preferable, if not
necessary, where the brush strip is subjected to brushing in either
rotational direction during the usage thereof.
As pointed out hereinbefore, the brush strip may be tightened on
the core merely by applying a sweeping load to the bristles of the
brush strip. However, a preferred way of tightening the brush strip
upon the core when the rotary broom is to be used in a powered
street sweeper is to mount the assembled core and brush strip on
the street sweeper machinery with the brush strip being in the
aforementioned loosened condition upon the core. The coils can then
be spaced by hand in the desired arrangement on the core as they
will be free to slide axially on the core at this time. The broom
core is next accelerated rapidly while it is elevated above the
ground surface. The quite large resulting inertia forces on the
brush strip cause the guide member 40 at the end thereof to travel
about the ring member 24 to fully take-up slack in the brush strip
and cinch the brush strip down tightly upon the surface of the
core. If a similar slack accumulator structure is provided at the
other end of the core, the foregoing procedure can then be repeated
with the brush being driven in the reverse direction.
From the foregoing description it will be recognized that the
rotary coiled broom assembly of the present invention provides a
means whereby a conventional helically coiled brush strip can be
tightened in place upon the conventional supporting core element.
Since the slack adjustment mechanism of the present invention
provides an endless amount of adjustment and does not leave a
freely extending end or projection of the brush strip, there is no
requirement whatsoever for initial hand tightening of the brush
strip upon the core during the broom assembly. Thus, the operator
need do no more than merely slide the brush strip upon the core,
attach some cotter pins or the like, and then mount the assembly
upon street sweeping equipment with the coils in the proper spacing
and such street sweeping equipment will then be ready to operate.
The take-up device of the present invention also eliminates the
necessity for providing a helical track or similar fixed spacing
means upon the surface of the core.
Although the best mode contemplated for carrying out the present
invention has been herein shown and described, it will be apparent
that modification and variation may be made without departing from
what is regarded to be the subject matter of the invention.
* * * * *