Note: Descriptions are shown in the official language in which they were submitted.
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TITLE OF THE INVENTION:
Brake For A Boom Mounted Free Swinging Working Member
NAMES) OF INVENTOR(S):
James Russell McKay
FIELD OF THE INVENTION
The present invention relates to a brake for a boom
mounted free swinging working member
BACKGROUND OF THE INVENTION
There are numerous applications which require a working
member to be mounted so that it swings freely from a boom.
These free swinging working members are sometimes referred to
as "dangle heads". Such working members, are used in a number
of applications in the forestry industry on equipment such as
grapple log skidders, tree harvesting heads, and log loader
grapples.
Depending upon the application, free swinging working
members can be used without a brake, if suitable care is taken
by the operator. In other applications, the working member is
subj ect to such violent swinging movements that the operational
life of the equipment is drastically reduced in the absence of
suitable braking devices which moderate the swinging movement.
In the forestry industry, the use of some form of braking
device is, almost without exception, a necessity. For example,
a grapple log skidder must move over uneven ground. In the
process of doing so, the wheels of the grapple log skidder
mount and descend obstacles which causes a side to side
movement of the grapple log skidder. Grapple log skidders have
a pincer-form grapple dangling at the end of a boom. When the
pincer-form grapple is holding some logs, the weight of the
logs helps to modify the swinging movement of the pincer-form
grapple. However, when the pincer-form grapple is not under
load, it swings wildly and smashes against the boom in the
absence of a brake.
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There are a number of brakes used with free swinging
working members. One of the most effective consists of a
series of steel plates with fibre braking disks sandwiches in
between the steel plates. The assembly of disks has a center
hole which accommodates a coupler pin. A tightening nut
attaches to the coupler pin to exert a clamping pressure upon
the disks. As the working member swings, there is friction
generated between the plates which moderates the swinging
movement. The brake is, of course, only effective if a
sufficient degree of friction is present. For that reason, as
the fibre braking disks wear, the tightening nut must be
further tightened to increase the clamping pressure. This
requires frequent adjustments by a conscientious worker.
Unfortunately, some workers are not sufficiently conscientious
to adjust the clamping pressure as frequently as they should.
It will be understood that the wear condition of the fibre
braking plates must be monitored, and the fibre braking plates
periodically replaced.
SUI~2ARY OF THE INVENTION
What is required is an alternative form of brake for a
boom mounted free swinging working member that requires less
frequent adjustment and maintenance.
According to the present invention there is provided a
brake for a boom mounted free swinging working member which
includes a male body and a female body. The female body has
a receptacle and a mounting bracket. The mounting bracket is
adapted to be mounted to either the boom or a coupling securing
the working member to the boom, so as to position the
receptacle along a pivot axis that defines relative pivotal
movement of the boom and the coupling for the working member.
The receptacle has a peripheral sidewall. The male body has
a mounting bracket adapted to be mounted to the other of the
boom and the coupling for the working member. The male body
has a member positioned in the receptacle of the female body.
A resilient material is positioned in between the member of the
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male body and the peripheral sidewall of the receptacle of the
female body. The resilient material dampens relative
rotational movement of the male body and the female body about
the pivot axis.
The brake, as described above, does not require operator
adjustment, nor does it require as frequent maintenance. The
resilient material would, typically, be an elastomer compound.
The brake will continue to function as long as the elastomer
compound maintains its resilience, which it is anticipated will
provide for a long operation life when compared to the life of
the fibre braking plates used in the prior art.
BRIEF DESCRIPTION OF THE DRAV~IINGS
These and other features of the invention will become more
apparent from the following description in which reference is
made to the appended drawings, wherein:
FIGURE 1 is a perspective view of a brake for a boom
mounted free swinging working member constructed in accordance
with the teachings of the present invention in a first
rotational position.
FIGURE 2 is an end elevation view, in section, of the
brake illustrated in FIGURE 1.
FIGURE 3 is a perspective view of the brake illustrated
in FIGURE 1, in a second rotational position.
FIGURE 4 is an end elevation view, in section, of the
brake illustrated in FIGURE 3.
FIGURE 5 is a perspective view of a boom mounted free
swinging working member equipped with the brake illustrated in
FIGURE 1.
FIGURE 6 is a detailed side view of the brake secured to
the boom mounted free swinging working member illustrated in
FIGURE 5.
FIGURE 7 is an exploded perspective view of an alternative
embodiment of a brake for a boom mounted free swinging working
member constructed in accordance with the teachings of the
present invention (component parts not to scale).
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment, a brake for a boom mounted free
swinging working member generally identified by reference
numeral 10, will now be described with reference to FIGURES 1
through 6. An alternative embodiment for a brake assembly for
a boom mounted free swinging working member, generally
identified by reference numeral 100, will be described with
reference to FIGURE 7.
Referring to FIGURES 5 and 6, brake for a boom mounted
free swinging working member 10 includes a first brake assembly
11, a second brake assembly 12, and a working member 14 freely
swinging from a remote end 15 of a boom 16. Working member 14
is suspended from boom 16 and swings freely about a first pivot
axis 18 and a second pivot axis 20. In most installations,
each of first pivot axis 18 and second pivot axis 20 will be
substantially horizontal, with first pivot axis 18
substantially at right angles to second pivot axis 20.
Referring to FIGURE 6, first brake assembly 11 has a first
female body 22 and a first male body 24. Second brake assembly
12 has a second female body 23 substantially similar to first
female body 22 and a second male body 25 substantially similar
to first male body 24. Referring to FIGURE 1 and using first
brake assembly 11 as representative of both first brake
assembly 11 and second brake assembly 12, first female body 22
has a first end 26 and a second end 28. A mounting bracket 30
is positioned at first end 26 of first female body 22.
Mounting bracket 30 has a first end 32, a second end 34, a
first face 36 and a second face 38. Referring to FIGURE 5,
First mounting bracket 30 is securable to either boom 16 or a
coupling 17 by which working member 14 is secured to boom 16,
as will hereinafter be further described. Referring to FIGURE
1, mounting bracket 30 is securable by passing bolts 40 through
bolt receiving passages 42 at second end 34 of first mounting
bracket 30. A first receptacle 44 extends in an offset
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cantilever fashion from first end 32 of mounting bracket 30 of
first female body 22. Referring to FIGURE 6, first receptacle
44 is positioned along first pivot axis 18. Referring to
FIGURE 2, first receptacle 44 has a peripheral sidewall 46
5 defining an interior passage 48. Referring to FIGURE 1, first
male body 24 has a first end 50 and a second end 52. A
mounting bracket 54 is positioned at first end 50 of first male
body 20. Mounting bracket 54 has a first end 56, a second end
58, a first face 60 and a second face 62. Mounting bracket 54
is securable to either boom 16 or a coupling 17 by which
working member 14 is secured to boom 16, as will hereinafter
be further described. This is accomplished by passing bolts
40 through bolt receiving passages 42 at second end 58 of
mounting bracket 54. A first member 60 extends from first face
60 at second end 58 of third mounting bracket 54. First member
60 is positioned in the first receptacle 44 of the first female
body 22. Referring to FIGURE 2, a resilient material 62, such
as rubber or elastomer plastic, is positioned in passage 48 in
between first member 60 of first male body 24 and peripheral
sidewall 46 of first receptacle 44 of first female body 22.
Resilient material 62 dampens relative rotational movement of
first male body 24 and first female body 22 about first pivot
axis 18, as will hereinafter be further described. Referring
to FIGURE l, a first end cap 64 is at second end 52 of first
male member 24.
Referring to FIGURES 1 and 3, first female member 22 and
first male member 24 are mutually rotatable about first pivot
axis 18 between a relaxed starting position illustrated in
FIGURES 1, 2 and a torsional braking position illustrated in
FIGURES 3, 4. When first female body 22 is rotated relative
to first male body 24 about pivot axis 18, as illustrated in
FIGURE 3, resilient material 62 is subjected to a torsional
compressive force, as illustrated by lines 66 in FIGURE 4.
Resilient material 62 resists the torsional force, and thereby
dampens the rotational movement about first pivot axis 18.
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As previously indicated, the operation of second brake
assembly 12 parallels that of first braking assembly 11.
Referring to FIGURE 6, second female body 23 of second brake
assembly 12 has a second receptacle 45 positioned along second
pivot axis 20, extending from a mounting bracket 31. A second
member 61 extends from a securing member 55 of second male body
25 and is positioned in the second receptacle 45 of second
female body 23. Referring to FIGURE 5, second male body 25 has
a second end cap 65. Resilient material 62 is positioned
between second member 61 of second male body 25 and receptacle
45 of second female body 23, which dampens relative rotational
movement of second male body 25 and second female body 23 about
second pivot axis 20.
Referring to FIGURES 5 and 6, brake 10 is mounted as will
now be described. As movement about more than one axis is
desired in the illustrated application, coupling 17 includes
a universal joint member 68 which is mounted by means of a
first pivot 70 to remote end 15 of boom 16. Universal joint
member 68 is required in order to accommodate second pivot axis
20 at substantially 90 degrees to first pivot axis 18. If
movement were restricted to about a single axis 18, universal
joint member 68 would not be required. First male body 24 is
mounted to remote end 15 of boom 16. First female body is
mounted to universal member 68, so that first pivot 70, first
receptacle 44 and first pivot axis 18 are collinear. Working
member 14 is mounted to universal member 68 by means of a
second pivot 72. Second female body 23 is mounted to universal
member 68 so that second pivot 72, second receptacle 45 and
second pivot axis 20 are collinear. Second male body 25 is
mounted to working member 14. In the illustrated embodiment
working member 14 is a grapple. It will be recognized that
alternative working members 14 can be suspended from boom 16
in a like manner. It will be recognized that an alternative
mounting arrangement will have first female body 22 mounted to
remote end 15 of boom 16 and f first male body 24 mounted to
universal member 68. It will be recognized that another
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alternative mounting arrangement will have second female body
23 mounted to working member 14 and second male body 25 mounted
to universal member 68.
Referring to FIGURE 7, there is illustrated an alternative
embodiment of brake assembly 100. Whereas brake 10 described
above is intended for external mounting. brake assembly 100 is
intended for internal mounting. Brake assembly 100 has a
female body 122 and a male body 124. Female body 122 has a
first end 126 and a second end 128 and peripheral sidewalls 146
defining an interior passage 148 with a square cross-sectional
shape extending the length of an axis 118 of female body 122.
Male body 124 has a first end 150 and a second end 152. Male
body 124 extends through interior passage 148 and past each of
first end 126 and second end 128 of female body 122 along axis
118. A resilient material 162, such as rubber or elastomer
plastic, is positioned in passage 148 in between male body 124
and peripheral sidewall 146 of female body 122. A rectangular
cross-sectioned groove 202 extends diagonally between opposed
corners 204 of each of first end 150 and second end 152 of male
body 124. A pair of collars 206 is provided, each collar 206
having a first face 208 and a second face 210. Each collar 206
has a passage 212 extending from first face 208 to second face
210. Passage 212 is square and has interior dimensions sized
to closely receive one of first end 150 or second end 152 of
male body 124. A pair of securing plates 214 is provided.
Each of securing plates 214 has external dimensions sized to
fit closely within groove 202 at one of first end 150 or second
end 152 of male body 124. Each securing plate 214 has bolt
holes 216. When securing plate 214 is located in groove 202
bolt holes 216 are aligned with bolt receiving holes 218 at
either of first end 150 or second end 152 of male member 124.
One of collars 206 is secured about each of first end 150 and
second end 152 by one of securing plates 214 that is bolted to
male body 124 by securing bolts 220 into bolt receiving holes
218.
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Brake assembly 100 is secured to a boom (not shown) and
a free swinging working member (not shown) by means of a
coupler 222. Coupler 222 has first body 224 and a second body
226 receivable within a cavity 228 in first body 224 between
spaced apart arms 236 extending from a main portion 238 of
first body 224. One of first body 224 and second body 226 is
secured to one of the boom (not shown) and the free swinging
working member (not shown) and the other of the first body 224
and the second body 226 is secured to the other of the boom and
the free swinging working member. Second body 226 has a square
cross-sectioned passage 230 extending from a first end 232 to
a second end 234. Passage 230 in second body has dimensions
sized to closely receive peripheral sidewalls 146 of female
body 122. Coaxial circular passages 240 extend throughout each
of spaced apart arms 236 extending from first body 224. The
diameter of each of circular passages 240 is sized to allow
each of first end 150 or second end 152 of male body 124 to be
received within one of circular passages 240 when female body
122 is received within second body 226 located within cavity
228 in first body 224, and for male body 124 to freely rotate
within circular passages 240 when male body 124 is so received.
Collars 206 secured at each of first end 150 and second end 152
of male body 124, as described above, secure brake assembly 100
within coupling member 222.
Brake assembly 100 is installed onto coupling member 222
as will now be described. Second body 226 is installed within
cavity 228 of first body 224 of coupling member 222 so that
circular passages 240 and square cross-sectioned passage 230
are coaxial. The combination of female body 122 and male body
124 is inserted along pivot axis 118 through each of circular
passages 240 until female body 122 extends through square
cross-sectioned passage 230 in second body 226 of coupling
member 222. One of collars 206 is secured at each of first end
150 and second end 152 of male member 124 using securing plates
214 and bolts 220. When brake assembly 100 is installed on
coupling member 222 as described above, mutual rotation of
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female member 122 and male member 124 about pivot axis 118 is
damped by the resistance to the mutual rotation provided by
resilient material 162.
It will be apparent to one skilled in the art that
modifications may be made to the illustrated embodiment without
departing from the spirit and scope of the invention as
hereinafter defined in the Claims.
