Note: Descriptions are shown in the official language in which they were submitted.
CA 02690547 2013-04-23
CABLE TENSION MEASUREMENT IN A VEHICLE EMERGENCY BRAKE CABLE ASSEMBLY
FIELD OF THE INVENTION
[0001] The present invention relates to the calibration of cables in cable
assemblies, such as
emergency brakes for automotive vehicles.
DESCRIPTION OF THE RELATED ART
[00021 The parking brake, also known as an emergency brake, controls the
rear brakes through a
series of brake cables that are connected to either a hand or a foot actuated
lever. The brake cables may act
between two fixed points to impart a force to actuate brake drums or calipers
when one end is pulled by the
lever. Actuation by hand or foot commonly employs a bracket joining two cables
so that they may be
commonly actuated to impart uniform brake force to a drum or caliper.
[0003] Installation and maintenance of the emergency brake can be an
imprecise process. A
common method of installing an emergency brake on vehicles is firstly to
assemble the emergency brake
parts on the vehicle. The tension of the brake cables is then adjusted to a
desired level by tightening an
adjustment nut on the bracket. The actual tension in the brake cables, which
is important to the proper
functioning of the emergency brake, is not directly known during the
installation and maintenance process.
This indirect tension measurement has limited measurement accuracy, and thus
causes tension to be out of
the specified range. For example, upon activation of the emergency brake
(parking brake), by the operator
of the vehicle as per their basic knowledge of the actuation method, the
emergency brake may impart a
reduced cable tension, which in turn may cause a vehicle to roll down a hill
[00041 It would therefore be desirable to obviate or mitigate the above
mentioned disadvantages, or
to provide a novel approach.
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SUMMARY OF TI IF GENERAL INVENTIVE CONCEPT
100051 In an exemplary' embodiment, there is provided a device for
measuring cable tension in a
vehicle emergency brake cable assembly. of a type having a pair of cables,
each for braking a
corresponding rear vehicle wheel. The device comprises a body for location
adjacent with the cables. The
body includes a first pair of opposed reaction portions. each arranged to
engage a corresponding cable. The
opposed reaction portions are positioned to locate the cables at a first
lateral spacing. The body supports a
load cell, which is positioned near the first pair of opposed reaction
portions. 'Elle load cell includes a pair
of opposed contact portions, each contact portion to engage a corresponding
cable. The opposed contact
portions are positioned to locate the cables beyond the first lateral spacing
to a second lateral spacing. The
load cell is configured to generate a signal representative of a load exerted
by the cables on the opposed
contact portions. An output portion provides an output signal indicative of
the load.
100061 In some exemplary embodiments, the body is positionable adjacent an
inner region between
the cables. The first pair of opposed reaction portions are arranged to be
located in the inner region, with
each reaction portion to engage a corresponding cable.
100071 In some exemplary embodiments, the cables define an inner region
therebetween and a pair
of opposed outer regions beyond the cables, each reaction portion being
arranged to be located in a
corresponding outer region.
100081 In some exemplary embodiments, the first pair of opposed reaction
portions include a first
pair of rollers.
100091 Some exemplary embodiments further comprise a second pair of
rollers, the load cell being
located between the first and second pairs of rollers.
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100101 In some exemplary embodiments, each of the first and second pairs of
rollers have a common
spacing.
100111 In some exemplary embodiments, the cables are joined at one end with
an equalizer bracket.
The body includes an alignment member for engaging and aligning the equalizer
bracket, in order to
position the first and second cables relative to the first and second rollers.
100121 In some exemplary embodiments, the equalizer bracket includes a pair
of fingers to engage
spaced regions on the equalizer bracket.
100131 In some exemplary embodiments, the cables include an inner cable
member and an outer
jacket, the outer jacket being attached to an anchor plate. while the body
includes an alignment portion for
aligning the body relative to the anchor plate.
100141 In some exemplary embodiments, the body further comprises a magnet
for clamping the body
to the anchor plate.
100151 In some exemplary embodiments, each of the contact portions
including a contact pad.
100161 In some exemplary embodiments, each contact pad has a first beveled
region for contacting
the corresponding cables when being located in the inner region.
100171 In some exemplary embodiments, the output portion includes a message
portion for
conveying a message corresponding to the output signal.
100181 Some exemplary embodiments further provide a tool for tightening the
cables. The tool
includes a drive motor and a switch portion for activating the drive motor. An
output portion is in
communication with the switch portion over a wired or wireless communication
link. The switch is
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responsive to a signal from the output portion for adjusting an operative
state of the tool according to a
predetermined tension force is present in a corresponding cable.
100191 In yet another exemplary embodiment, there is provided a method for
measuring cable
tension in a vehicle emergency brake cable assembly, of a type having a pair
of cables. each for braking a
corresponding rear vehicle wheel, comprising:
- locating a first pair of opposed reaction portions in a region adjacent
the pair
of cables, so that each reaction portion contacts and positions a
corresponding
cable at a first operative position with the pair of cables at a first lateral
spacing beyond a neutral spacing,
- providing a load sensing unit with a pair of cable engaging elements,
with
each cable engaging element positioning a corresponding cable at a second
operative position to bring the pair of cables to a second lateral spacing
beyond the first lateral spacing; and
- activating a signal generating portion to generate a signal indicative of
a load
exerted on the elements by the cables and representative of tension in the
cables.
100201 Some exemplary embodiments further comprise activating a display
unit to receive the signal
and to convey a message representative of the tension in the cables.
100211 Some exemplary embodiments further comprise dispatching the signal
along a data path to a
hand tool with a signal receiving portion to receive the signal, and
activating a switch to turn off the tool
when the signal indicates a threshold tension in the cables.
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100221 In yet another exemplary embodiment, there is provided a device for
measuring cable tension
in a cable assembly, of a type having a pair of cables. the cables being
positioned by an anchor member.
The device comprises a body for location adjacent the anchor member. The body
includes a locating
portion for locating the body in an operative configuration relative to the
anchor portion. The body
supports a pair of opposed contact portions. each contact portion arranged to
engage a corresponding cable.
A load sensing unit is operatively coupled with the opposed contact portions
to generate a signal
representative of a load to be exerted on the contact portions when the cables
are under an operative
tension. An output portion is also to provide an output signal indicative of
the load.
100231 In some exemplary embodiments, the load sensing unit includes a load
cell.
100241 Some exemplary embodiments, further comprises a first pair of
opposed positioning portions.
each for positioning a corresponding cable.
100251 Some exemplary embodiments further comprise a second pair of opposed
positioning
portions, each for positioning a corresponding cable, the first and second
pairs having a common spacing.
100261 In some exemplary embodiments, each of the opposed positioning
portions of the first and
second pairs including a roller, the load cell being centrally located
therebetween.
100271 In some exemplary embodiments, the rollers are arranged to establish
each of the cables in a
first lateral spacing. The opposed contact portions are arranged to locate the
cables beyond the first lateral
spacing to a second lateral spacing.
100281 In some exemplary embodiments, the rollers are arranged to displace
the cables inwardly
toward one another to the first lateral spacing.
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100291 In some exemplary embodiments, the rollers are arranged to displace
the cables outwardly
away from one another to the first lateral spacing.
100301 In some exemplary embodiments, the opposed contact portions are
arranged to displace the
cables inwardly toward one another to the second lateral spacing.
100311 In some exemplary embodiments. the opposed contact portions are
arranged to displace the
cables outwardly away from one another to the second lateral spacing.
100321 In still another exemplary embodiment, there is provided a device
for measuring cable
tension in a cable assembly, of a type having two or more cables and providing
a reference location relative
to the cables. -Hie device comprises a body for location adjacent the
reference location. The body includes
a locating portion for locating the body in an operative configuration
relative to the reference location. The
body supports two or more contact portions. each contact portion arranged to
engage a corresponding
cable. A load sensing unit is operatively coupled with the opposed contact
portions to generate a signal
representative of a load to be exerted on the contact portions when the cables
are under an operative
tension.
100331 In some exemplary embodiments, the cable assembly includes an
equalizer bracket defining
the reference location and the body includes a plurality of alignment
formations for aligning the body in a
predetermined orientation adjacent the equalizer bracket.
100341 In some exemplary embodiments, the equalizer bracket includes a pair
of opposed peripheral
regions, each alignment formation being configured to engage a corresponding
peripheral region.
100351 In some exemplary embodiments, a first of the peripheral regions
includes a central
mounting location for receiving a brake lever cable portion therein, and a
first pair of the alignment
formations are arranged to receive the central mounting location therebetween.
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100361 In yet another exemplary embodiment, there is provided a method for
measuring cable tension
in a cable assembly, of a type having a pair of cables. comprising:
locating each of a first pair of opposed reaction portions adjacent a
corresponding cable, so that each reaction portion contacts and positions the
corresponding cable at a first operative position with the pair of cables at a
first lateral
spacing beyond a neutral cable spacing.
locating each of a pair of cable engaging elements adjacent a corresponding
cable, so that each element positions the corresponding cable at a second
operative
position with the pair of cables at a second lateral spacing beyond the first
lateral
spacing; and
activating a signal generating portion to generate a signal indicative of
forces
exerted on the elements and representative of tension in the cables.
100371 In still another exemplary embodiment, there is provided a cable
assembly according to the
method herein.
100381 In yet another exemplary embodiment, there is provided an automotive
vehicle comprising a
cable assembly as defined herein.
BRIEF DESCRIPTION OF THE DRAWINGS
100391 Several exemplary embodiments of the present invention will be
provided, by way of
examples only, with reference to the appended drawings, wherein;
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100401 Figure I is a fragmentary perspective view of a cable tension
measuring device:
100411 Figures 2 is a fragmentary bottom view of a portion of the device of
figure 1:
100421 Figure 2a is a fragmentary side view of a portion of an element
shown in figure 2:
100431 Figure 3 is a bottom view of the device of figure 1 in an operative
configuration with a drive
tool;
100441 Figure 4 is a schematic view of a portion of the device of figure 1;
100451 Figure 5 is an assembly view of another cable tension measuring
device;
100461 Figure 6 is another fragmentary side view of the device of figure 5;
100471 Figure 7 is a lower perspective view of the device of figure 5; and
100481 Figures 8 to 12 inclusive are schematic views of alternative cable
tension measuring devices.
DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
100491 It should be understood that the invention is not limited in its
application to the details of
construction and the arrangement of components set forth in the following
description or illustrated in the
drawings. The invention is capable of other embodiments and of being practiced
or of being carried out in
various ways. Also, it is to be understood that the phraseology and
terminology used herein is for the
purpose of description and should not be regarded as limiting. The use of
"including," "comprising," or
"having" and variations thereof herein is meant to encompass the items listed
thereafter and equivalents
thereof as well as additional items. Unless limited otherwise, the terms
"connected," "coupled," and
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"mounted," and variations thereof herein are used broadly and encompass direct
and indirect connections,
couplings, and mountings. In addition, the terms "connected" and "coupled" and
variations thereof are not
restricted to physical or mechanical connections or couplings. Furthermore,
and as described in subsequent
paragraphs, the specific mechanical configurations illustrated in the drawings
are intended to exemplify
embodiments of the invention. However, other alternative mechanical
configurations are possible which
are considered to be within the teachings of the instant disclosure.
Furthermore, unless otherwise indicated,
the term "or" is to be considered inclusive.
[00511 Referring to the figures, there is provided a device 10 for
measuring cable tension in a vehicle
emergency brake cable assembly 12, of a type having a pair of brake cables 14,
16, each for braking a
corresponding rear vehicle wheel, not shown. A variation to the device 10 is
shown in figure 5.
[0052] The device 10 has a body 20 for locating adjacent an inner region
"1" (figure 2) between the
cables 14, 16. The body 20 includes a handle 21 and two pairs of reaction
portions shown at 22,24 which
are arranged to be located in the inner region I and to engage the cables 14,
16. The reaction portions, in
this case, are rollers which spin on axle members 22a, 24a mounted on the
body. Each of the rollers 22, 24
includes a shoulder portion 22b, 24b with a relatively larger diameter to
control vertical position of the
cables 14, 16 and cable receiving portions 22c, 24c with a relatively smaller
diameter to at least partially
entrain the cables 14, 16. As can be seen in figure 2, the first and second
rollers 22,24 are positioned to
locate the cables 14, 16 at a first lateral spacing as can be seen at SI. The
body also supports a load cell
26 which is located between the first and second rollers 22, 24. An example of
a suitable load cell is model
LH 270, known as Miniature S-Beam Load Cell, commercially available from
COOPER INSTRUMENTS
& SYSTEMS. A pair of opposed contact portions 28 are aligned with the load
sensing sides of the load
cell 26. Each of the contact portions 28 is to be located in the inner region
I and to engage a corresponding
cable. The opposed contact portions are positioned to locate the cables beyond
the first lateral spacing Si
to a second lateral spacing 52, as shown in figure 2. As will be described,
the load cell 26 is configured to
generate, in this particular example, a signal representative of a compressive
load F exerted by the cables
14, 16 on the opposed contact portions 28. However, as will be
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discussed, other examples of the device 10 may be configured to sense tensile
loads. Referring to figures 2
and 2a. the opposed contact portions 28 are provided in the form of pads. each
of which has a beveled edge
region 28a to engage and deflect the corresponding cable when being located in
the inner region I. Each
pad 28 is also provided with a central recess 28b to assist in locating the
cable when each pad 28 is in an
operative position. Referring to figure 3, a base plate 29 is provided on a
distal side of the rollers 22, 24,
so that the rollers and the load cell 26 are held between the body 20 and the
base plate 29.
100521 Referring to figures I and 4, an output portion 30 is also provided
for providing an output
signal indicative of the compressive load F. while power to the output portion
is provided by battery 31
though other sources of power may be provided, as desired. In the example
shown in figure I. the output
portion 30 includes a message portion in the form of a display portion 32 in
which the output signal is
displayed in a digital representation of the tensile load in each of the
cables, expressed as a function of the
compressive load F exerted on the pads 28. In this case, the display portion
32 may include a 3 1/2 Digit,
LCD/LED Display. The representation of the tensile load in the cables may be
provided with
alphanumeric symbols, bar lines. by way of the display portion. Alternatively,
the display portion 32 may
be replaced with another form of message portion, such as an audio generator
for issuing an audio signal,
such as a synthesized voice or a tone pattern, either indicating that a target
tension level has been reached or
indicating incremental changes in tension level.
100531 The first and second rollers 22, 24, in this case, are equally
spaced, though other spacings
may also be contemplated depending on the configuration of the cables 14, 16.
The equal spacing of the
rollers 22, 24, in this case, is appropriate for the cables which are in a
parallel configuration.
100541 As can be seen in figure 1, the cables 14, 16 are joined at one end
with an equalizer bracket
plate 34. The cables 14, 16 are anchored at one end to the equalizer bracket
34 by way of pivot pins 14b.
The equalizer bracket 34 anchors a first end 35a of a pull cable 35, which
extends to a forward region of the
chassis near the instrument cluster (not shown), for instance, for coupling
with a emergency brake lever
assembly shown schematically at 33. Thus, a second end 35b of the pull cable
35 is adjustably positioned
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relative to the emergency brake lever assembly 33. by way of a threaded
fastener 33a. It will be understood
that the specific arrangement shown is merely exemplary.. The threaded
fastener, adjusting the position of
the pull cable, may in turn be indirectly coupled with the pull cable 35. The
couplings between the two
cables 14, 16 and pull cable 35 are pivoted couplings, allowing the equalizer
bracket 34 to position itself to
balance the tension on the two cables, thereby' accommodating variations in
length that may occur during
manufacturing.
100551 Attached to the body 20 is an alignment member 36 (figure 3) for
engaging and aligning the
equalizer bracket 34, in order to position the first and second cables 14, 16
relative to the first and second
rollers "r), 24.
100561 The alignment member 36 includes a pair of fingers 36a (figure 1) to
engage spaced regions
on the equalizer bracket 34 between the ends of cables 14 and 16.
100571 As can be seen in figure 1, each cable includes an outer jacket
portion which can be seen at
16a for cable 16. The outer jacket 16a is attached to an anchor plate 38,
which is mounted on a central
interior floor structure of a vehicle chassis (not shown). The body 20
includes a guide portion 40 for
aligning the body 20 relative to the anchor plate 38.
100581 The anchor plate 38 includes a base plate portion 42 and a pair of
opposed outer mounting
flange portions 44. Each forms a passage 44a for receiving a corresponding
outer jacket I4a therein.
Referring to figure 6, the anchor plate 38 further includes an upstanding post
42a, which extends into a gap
40a between guide portion 40 and a magnet 48.
100591 The magnet 48 is attached to the body 20 and provides a magnet
clamping force against the
anchor plate 38 for clamping the body 20 to the base plate portion 42.
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100601 The device 10 thus provides a technique for sensing the tensile
loads in a pair of
neighbouring cables. This is done by way of the load cell 26 sensing a load F
exerted by deflecting the
cables beyond a first position to a second position. The output portion 30 is
thus capable of recording the
load F. the higher the force, the greater the tension in the cables. Given the
balancing function of the
equalizer bracket 34, it can be reasonably assumed that the tensional forces
on the two cables are
substantially equal, so that the load F present at the load cell 26 can be
considered representative of the
tensional forces in both cables.
100611 The output portion 30 may thus be provided to present a graphical
representation of the
tensional forces on the cable by way of the display portion 32. In this case,
the output portion 30 includes
circuitry to associate the compressive force F with a corresponding tensile
force. The display portion 32
thus permits an Associate to monitor tensile forces on the cables while
adjusting the fastener 33a on the pull
cable 35. As the Associate turns the fastener 33a, the tension on the cables
increases (or decreases as the
case may be depending on the direction of turning), as indicated by the
increase in compressive load F
appearing at the pads 28 and presented in the display portion 32.
100621 As shown in figure 4, a 9V battery 31 is used to power the device
with a circuit. The battery
voltage is converted to 5V by a DC to DC converter 67 (for example available
under the trade name TDK
LAMBDA, model CC1R5-0505SF-E). The DC to DC converter 67 provides the load
cell 26 with a constant
excitation of 5V. The output portion 30 includes an instrumental amplifier 69
to receive an input signal
from the load cell (model INA 125). A microcontroller 68 (under trade name
ATMEL, model ATMegal6)
receives an amplified output from the amplifier 69.
100631 The microcontroller 68 is operable to convert the analog signal from
the load cell 26 into a
digital signal, to decode the signal, and to drive the LCD (liquid crystal
display) chip of the display portion
32. The microcontroller 68 may also be programmed to allow the associate to
scale the display according
to a predetermined unit of measure (i.e. pounds, Newton's, kg force).
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100641 The Associate may prepare the device 10 for use by first identif3
ing the cables 14 and 16 and
the region near the base plate portion 42 upwardly extending from the central
floor region of the vehicle.
The device 10 is then oriented by the handle 21 and placed in position so that
the rollers 22 and 24 are
aligned with the cables 14. 16. The device 10 is then lowered toward the
cables 14, 16 to displace the
cables with the rollers 22.24 to a first lateral spacing SI and the beveled
edge region 28a of the pads 28 to
make contact with and laterally displace the cables to the second lateral
spacing S2. Proper positioning
occurs when each of the cables engages the cable receiving region 22c, 24c of
the corresponding rollers 22.
24 and the central recess 28b of the pads 28. This position is then maintained
the fingers 36a of the
alignment member 36 positioned beneath of the equalizer bracket 34, the guide
portion 40 engaged with the
upstanding post 42a and the magnet in contact with the base plate portion 42.
The Associate may then
proceed to adjust the fastener 33a at the emergency brake lever assembly 33 to
tighten (or loosen) the pull
cable 35 as needed to bring the tension in the cables 14. 16 to the factory
setting. While adjusting the
fastener 33a, the Associate may watch the display 32 and then terminate the
adjustment when the tension
has indeed reached the factory setting.
100651 In another example, as shown in figures 3 and 4. the device 10 may
be configured to
communicate, over a wired or wireless data path 50. with a drive tool shown
schematically at 52 and a
transmitter 70 (under trade name TIT 418) to issue signals over the data path
50. The drive tool 52 is
provided with a signal receiver portion 54, in the form of a receiver chip
(under trade name RLP 418), to
receive a signal or a change in a signal on the data path 50, indicating that
a predetermined tension
threshold has been reached in the cables 14, 16. The drive tool 52 may be
further provided with a cut-off
switch function, in the form of a microcontroller 56 (under trade name ATMEL
ATMegal6). The
microcontroller 56 is responsive to the signal receiver portion 54 to control
the operation of a motor portion
58 which in turn drives an output drive member 60, which is joined to a socket
62, which is in turn
dimensioned to fit the fastener 33a on brake lever assembly 33. In this case,
the signal or change in signal
may be indicative for the switch function to terminate or to adjust power to
the motor portion 58, so as to
adjust the speed of, or stop, the socket 62. This arrangement has the
advantage that the drive tool 52 may
thus be automatically switched off when the cables 14, 16 are measured to be
under tension at a preset
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factory threshold, or other predetermined tension, thereby reducing the need
for an Associate to manually
shut off the drive tool 52 while viewing the display 32. The signals are
decoded by the microcontroller 56.
In one example, the microcontroller 56 is configured to employ a pulse width
modulation scheme to adjust
the speed of the drive tool, or to switch it off completely when the proper
cable tension has been reached.
100661 In this case, the data path 50 is dedicated for communications
between the device 10 and the
drive tool 52, for example operate under frequencies such as those referred to
as 'radio frequency' or "RF"
using protocols such as the 802.11, TCP/IP, BLUETOOTH and the like, or other
Internet, wireless,
satellite or cell packet protocols. The data path 50 and indeed the device 10
may be part of a larger
communication network in a number of forms, by way of one or more software
programs configured to run
on one or more general purpose computers, such as a personal computer, or on a
single custom built
computer. A system controlling such a communication network may,
alternatively, be executed on a more
substantial computer mainframe. The general purpose computer may work within a
network involving
several general purpose computers, for example those sold under the trade
names APPLE or IBM , or
clones thereof, which are programmed with operating systems known by the trade
names WINDOWS ,
LINUX or other well known or lesser known equivalents of these. The system
may involve pre-
programmed software using a number of possible languages or a custom designed
version of a programming
software. The computer network may be include a wired local area network, or a
wide area network such as
the Internet, or a combination of the two, with or without added security,
authentication protocols, or under
"peer-to-peer" or "client-server" or other networking architectures. While the
drive tool 52 collects
instructional data from data path 50 from the device 10, it may also
communicate status information to the
drive tool 52 or to a monitoring system controlled by a local computer or a
central server.
[0067] Thus, in some examples, the device 10 provides a hand held tool with
a handle, a fork at the
front of the tool, for lifting the cables and a magnet for holding the tool in
position between the cables. The
tool has a main body, at the bottom of which there is a pair of rollers per
side. Centered in between the
rollers is a pair of contact pads, each being on a corresponding side of the
main body. These pads are
guided inside the main body by the feature shape of the main body and are a
size to allow minimal side to
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side movement. The pads transfer any force exerted on them into a load cell
between them. On the bottom
of the body. there is provided a plate which retains the load cell, contact
pads and rollers. The function of
the rollers, in this example, is to displace the cables by the required amount
in order to provide for a
consistent bridged distance over the load cell contact pads. The load cell
contact pads displace the cable by
the required amount in order to provide a load measurement capability
converging from both sides of the
load cell through the contact pads. The power supply to the load cell and the
reading from the load cell
output is handled by an electronic circuit powered by a 9 volt battery. The
power is converted to the
correct excitation voltage by a DC to DC converter. The output device is a 3.5
digit LED Display. The
electronic circuit board and battery are enclosed inside a removable cover
which is located between the
handle and the main body at the bottom. There is a separate enclosure cover to
remove for access to the
battery. The rear of the tool contains a magnet on the lower side in order to
help retain the tool in the
desired position in the cable bracket mounted to the vehicle. There is a guide
bracket mounted under the
handle at the rear of the tool to guide the tool into position and also to
help retain the tool in the desired
position in the cable bracket. There is a small switch to turn on power to the
circuit. In another example.
the output of the device is utilized to automatically control a nut-driving
tool used to adjust the brake cable
system. The device thus sends a signal (such as by way of a wired or wireless
data path) to a drive tool
where the signal will be received and the power to the driving mechanism of
the DC tool will be cut,
causing the adjustment of the system to cease.
100681 In some examples, the device 10 provides a body which is
positionable adjacent an inner
region between the cables, where the opposed reaction portions (in one example
rollers) are arranged to be
located in the inner region, with each reaction portion to engage a
corresponding cable. However, in yet
several other examples, the cables may be seen to define an inner region
between them and a pair of
opposed outer regions beyond them.
100691 Figures 8 to 11 show variations of a device 71 for measuring cable
tension in a cable
assembly, of a type having a pair of cables 76. Thus, the device 71 can be
used for cable installations
beyond vehicle brake cable assemblies, such as cables in hydro distribution
systems, as but one example.
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In this case. the cables 76 are positioned by an anchor member shown
schematically at 78. The device 71
has a body 80 for location adjacent the anchor member 78. The body 80 includes
a locating portion 82 for
locating the body 80 in an operative configuration relative to the anchor
member 78. Thus, in this case, the
locating portion 82 allows for the body 80 to be located in a common location
from one cable assembly to
another (provided the specifications of the cable assemblies include a common
anchor member). The body
80 supports a pair of opposed contact portions 84, each contact portion 84
arranged to engage a
corresponding cable 74. Further, a load sensing unit 86 is operatively coupled
with the opposed contact
portions 84 to generate a signal representative of a load to be exerted on the
contact portions 84 when the
cables 74 are under an operative tension. An output portion (not shown) may
then be used to provide an
output signal indicative of the load. In each example, the load sensing unit
includes a load cell as described
above.
100701 In the example of figure 8, the opposed contact portions 84 are
arranged to displace the cables
74 inwardly toward one another from a first lateral spacing to a second
lateral spacing. On the hand, in
the example of figure 9, the opposed contact portions are arranged to displace
the cables outwardly away
from one another to the second lateral spacing.
100711 In the examples of figures 10 and II, the device 71 includes first
and second pairs of opposed
positioning portions 88, each for positioning a corresponding cable in
opposition to the opposed contact
portions. In each case, each of the positioning portions of the first and
second pairs includes a roller 88. the
load cell 86 being centrally located between them. In the case of figure 10,
the rollers 88 are seen in the
outer regions of the cables 74 to provide the first lateral spacing, with the
contact portions 84 displacing the
cables outwardly to the second lateral spacing. In contrast, in figure 11, the
rollers are located in the inner
region and the contact portions are displacing the cables inwardly to the
second lateral spacing.
100721 Thus, in the case of the device 71 of figures 9 and 10, the cables
76 are displaced slightly
outwardly when the device 71 is put in place. As the force in the cables is
increased through adjustment, the
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cables tend to move inward, causing a compression force to be exerted on the
load cell. The load cell
measures this compression force as a function of the actual tension in the
cables.
100731 On the other hand, with reference to figure 8 and II. when the
device 71 is placed in an
operative position with the cables 76. they are displaced slightly inwardly.
During adjustment. the cables
are forced to move outwards away from the load cell. A tension type load cell
is then able to measure this
tension force and it is interpreted by the output portion 30, as a function of
the actual tension in the cables
76.
100741 Referring to figure 12, still another device is provided at 90 for
measuring cable tension in a
cable assembly 92, of a type having a pair of cables 93 and providing a
reference location 96 relative to the
cables 93. In this case, the device 90 includes a body shown in dashed lines
at 94 for location adjacent the
reference location 96. The body 94 includes a locating portion 98, in this
case in the form of a base plate or
the like, for locating the body 94 in an operative configuration relative to
the reference location 96. The
body supports a pair of opposed contact portions 100, each contact portion 100
arranged to engage a
corresponding cable 93 and a load sensing 102 unit operatively coupled with
the opposed contact portions
100 to generate a signal representative of a load to be exerted on the contact
portions when the cables are
under an operative tension. An output portion, shown schematically at 104, may
also be provided to signal
when a predetermined load is present in the cables 93.
100751 The cable assembly 92 includes an equalizer bracket 106 defining the
reference location 96
and the body 94 includes a plurality of first and second alignment formations
108, 110, respectively, for
aligning the body 94 in a predetermined orientation adjacent the equalizer
bracket 106. The equalizer
bracket 106 has, in this case, a pair of opposed peripheral regions 106a, 106b
and each alignment formation
108, 110 is configured to engage a corresponding peripheral region. A first of
the peripheral regions 106a
includes a central mounting location 112 for receiving a brake lever cable
portion (not shown) therein,
while the first pair of the alignment formations 108 are arranged to receive
the central mounting location
112 therebetween. In this case, the first and second formations 108, 110 may
be, for instance, projections
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extending outwardly from the body 94 and may further include bumpers, rollers,
wheels, bearings or the
like. Alternatively, the adjustment formations may include one or more pins
shown schematically at 114,
= which are configured to extend into complementary passages 116, wherein
the pins and passages are
' respectively located in the location portion 98 and the
equalizer bracket 106, or vice versa.
[0076] The arrangement of figure 12 thus provides the device
90 for measuring cable tension while
enabling a technique for locating the device at or near a common reference
location from one cable pair or =
cable set to another, without necessary needing to anchor the device itself to
a particular anchor location on
a frame supporting the cable set, such as an anchor location on a vehicle
chassis. Thus, in the specific
example of a device for use in vehicle chasses, the device 90 may utilize a
physical location on the cable set
itself, such as in this case the front cable equalizer bracket 106, as a guide
to hold the device or fixture in
place, in cases where the front equalizer is a common element among the
vehicles of a particular model
being assembled. Further variations of the device and method as described
herein may be used to measure
and/or balance loads in more than two cables as desired, by providing at least
one load cell with an ability
to sense loads therein and which may include at least one output portion to
signal when a predetermined
load is reached.
[0077] While the present invention has been described for
what are presently considered the
preferred embodiments, the invention is not so limited. To the contrary, the
invention is intended to cover
various modifications and equivalent arrangements included within the spirit
and scope of the appended
claims.
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=
