Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02560299 2009-09-08
CABLE TIE TOOL HAVING VARIABLE TRIGGER LINKAGE
BACKGROUND OF THE INVENTION
The present invention relates generally to a cable tie tool having a variable
trigger
linkage, and more specifically, to such a trigger linkage which may provide
different
tensioning forces to the tool head of the cable tie tool.
Cable ties are used to bundle or secure a group of articles such as electrical
wires or
cables. Cable ties of conventional construction include a cable tie head and
an elongate strap
extending therefrom. The strap is wrapped around a bundle of articles and
thereafter inserted
through a passage in the head. The head of the cable tie typically supports a
locking element
which extends into the head passage allowing the strap to be inserted through
the passage but
preventing retraction of the strap through the passage in the head. Two
longitudinally
separated portions of the strap are thereby secured to the head to define a
loop for holding
together the group of articles.
In use, the installer manually places the tie about the articles to be
bundled, inserts the
strap through the head passage and then manually tightens the tie about the
bundle. Further
tightening of the cable tie, which increases the tension in the strap thereof,
may be provided
by a cable tie tool.
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
One type of such a cable tie tool includes a handle which is generally pistol-
shaped and
has a barrel into which the strap maybe inserted for application of the
tension thereto. The
handle has a grip which depends from the barrel. The tool includes a trigger
mechanism a
portion of which is supported within a trigger housing located under the
barrel and in front of
the grip. The trigger housing is elongate and in generally depending relation
relative to the
barrel such that, when the heel of the hand of a user is placed against the
grip such that the
fingers of the hand of the user extend forwardly, the fingers may encircle the
forward surface
of the trigger housing. Forcibly drawing the fingers toward the heel of the
hand, such as by
squeezing the trigger housing and grip, causes the trigger housing to be
displaced toward the
grip. The trigger mechanism is also supported within the barrel and is able to
grasp the strap,
and to apply the tension thereto in proportion to the drawing or squeezing
force applied to the
trigger housing.
The ratio of the tension force applied to the cable tie to the drawing or
squeezing force
applied to the trigger housing is frequently constant and determined by the
trigger
mechanism. As a result, if an increased tension force is to be applied to the
cable tie, a
correspondingly larger drawing or squeezing force is required to be applied to
the trigger
housing.
The application of larger tension forces to a cable tie is frequently required
as a cable
tie is tensioned because the cable tie normally resists further tensioning
after having been
subjected to previous tension, particularly if such previous tension is
substantial. This, in
turn, frequently requires the application of increased drawing or squeezing
forces to the
trigger housing which are normally provided by the hand of the user. If the
required drawing
2
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
or squeezing forces become sufficiently large, the hand of the user may
encounter difficulty
in providing such forces.
SUMMARY OF THE INVENTION
The cable tie tool of the present invention includes a tool handle having a
barrel
structure and a tool head supported within the barrel structure. The tool head
has a forward
end to which may be secured a cable tie for tensioning thereof.
An elongate lever is supported within the tool handle by a pivotal connection
thereto.
The lever has near and distant positions thereon which have corresponding
longitudinal
reduced and increased separations from the pivotal connection. The lever is
coupled to the
tool head and pivotal between neutral and tensioned positions such that, when
a cable tie is
secured to the tool head, pivoting the lever from the neutral to tensioned
positions causes the
lever to apply a force to the tool head to increase the tension in the cable
tie in proportion to
the force applied to the tool head by the lever.
The cable tie tool includes a variable trigger linkage supported within the
tool handle
by a connection thereto. The trigger linkage is coupled to the lever and
movable between
open and closed positions such that moving the trigger linkage from the open
to closed
positions causes the lever to pivot from the neutral to tensioned positions.
The trigger linkage
engages the lever alternatively at the near or distant positions to provide
the coupling to the
lever such that, when a uniform force is applied to the trigger linkage for
movement thereof
from the open to closed positions, the engagement at the distant position
results in the force
applied to the tool head by the lever being greater than the force applied to
the tool head by
the lever which results from the engagement at the near position.
3
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
The variable trigger linkage provides for the application of two different
forces by the
lever to the tool head depending upon whether the trigger linkage engages the
lever at the
near or distant positions thereon. Since the tension force applied to the
cable tie by the tool
head is related to the force applied thereto by the lever, different tension
forces are applied to
the cable tie by the tool head depending upon the force applied thereto by the
trigger linkage.
The application of different tension forces to a cable tie by the trigger
linkage
provides for the application of a greater tension force as the cable tie is
progressively
tensioned. This is advantageous because progressive tensioning of the cable
tie will
frequently require the application of higher tension forces thereto. The
variable trigger
linkage provides for the application of such higher tension forces from the
application of a
uniform drawing or squeezing force to the trigger linkage by the user. As a
result, an
increased drawing or squeezing force by the hand of the user is not required
for the trigger
linkage to apply the increased force to the tool head and, consequently, to
the cable tie. The
user, and more particularly the hand thereof, is thereby relieved of the
difficulties associated
with having to apply increasing large drawing or squeezing forces to the
trigger linkage and
grip.
These and other features of the invention will be more fully understood from
the
following description of specific embodiments of the invention taken together
with the
accompanying drawings.
4
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
Fig. 1 is a right side perspective view of a cable tie tool containing a
variable trigger
linkage of the present invention;
Fig. 2 is an exploded view of the cable tie tool of Fig. 1, the tool head and
left section
of the tool handle being removed to show the variable trigger linkage;
Fig. 3 is a left side perspective view of the trigger frame of Fig. 2;
Fig. 4 is a left side elevation view of the trigger frame of Fig. 3;
Fig. 5 is a front elevation view of the trigger frame of Fig. 3;
Fig. 6 is a front elevation view corresponding to Fig. 5 showing the trigger
frame in a
planar configuration before bending thereof to the configuration shown in Fig.
3;
Fig. 7 is a side elevation view of the cable tie tool of Fig. 1 showing the
left section of
the tool handle removed, the variable trigger linkage being shown in the open
position and
having the automatic gear engaged, the hand-size adjustment of the variable
trigger linkage
being shown for a large hand;
Fig. 8 is a side elevation view corresponding to Fig.7 showing the variable
trigger
linkage in the closed position;
5
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
Fig. 9 is a side elevation view of the cable tie tool of Fig. 1 showing the
left section of
the tool handle removed, the variable trigger linkage being shown in the open
position and
having the automatic gear engaged, the hand-size adjustment of the variable
trigger linkage
being shown for a small hand;
Fig. 10 is a side elevation view corresponding to Fig.9 showing the variable
trigger
linkage in the closed position;
Fig. I 1 is a side elevation view of the cable tie tool of Fig. 1 showing the
left section
of the tool handle removed, the variable trigger linkage being shown in the
open position and
having the fixed gear engaged, the hand-size adjustment of the variable
trigger linkage being
shown for a large hand;
Fig. 12 is a side elevation view corresponding to Fig. 11 showing the variable
trigger
linkage in the closed position;
Fig. 13 is a side elevation view of the cable tie tool of Fig. 1 showing the
left section
of the tool handle removed, the variable trigger linkage being shown in the
open position and
having the fixed gear engaged, the hand-size adjustment of the variable
trigger linkage being
shown for a small hand; and
Fig. 14 is a side elevation view corresponding to Fig.13 showing the variable
trigger
linkage in the closed position.
6
CA 02560299 2009-09-08
Corresponding reference characters indicate corresponding parts throughout the
several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings and more particularly Figs. 1, 2, and 7, a cable tie
tool 20 is
shown for securing a cable tie 22 to a bundle of articles, such as wires or
cables. The cable
tie tool 20 includes a tool handle 24 having a pistol-shape. The tool handle
24 includes a
barrel structure 26 and a grip structure 28 which depends from the barrel
structure. The grip
structure 28 has an outer surface 30 which is grasped by the palm of the hand
of a user when
the tool handle 24 is grasped by the user. The barrel structure 26 has
elongate cavity 30 and
an open forward end 31 which provides access thereto. The tool handle 24 has
left and right
sections 32, 33 which are held together by pins 34.
As used herein, the "rearward direction" indicates the direction, for example,
from the
forward end 31 to the grip structure 28. The "forward direction" indicates the
direction
which is opposite to the rearward direction. "Left" and "right" indicate the
sides of one
which is facing in the forward direction.
The cable tie tool 20 includes a tool head 35 which is supported within the
cavity 30
of the barrel structure 26. The tool head 35 has a forward end 36 to which the
cable tie 22 is
secured for tensioning thereof. Examples of the tool head 35 are disclosed in
U.S. Patent
No. 5,915,425, U.S. Patent No. 7,231,944, and U.S. Patent No. 7,216,679.
7
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
The cable tie tool 20 includes elongate left and right levers 38, 39 each of
which is
supported within the tool handle 24 by a lever pin 40 which is supported on
the inner surface
of the grip structure 28. The lever pin 40 provides a pivotal connection
between the levers
38, 39 and the grip structure 28 for pivoting of the levers between neutral
and tensioned
positions 42, 44.
The levers 38, 39 are coupled to the tool head 35 such that, when the cable
tie 22 is
secured to the tool head 35, pivoting the levers 38, 39 from the neutral to
tensioned positions
42, 44 causes the levers to apply a force to the tool head to increase the
tension in the cable
tie in proportion to the force applied to the tool head by the levers. The
levers 38, 39 each
have near and distant positions 46, 48 thereon which have respective
longitudinal reduced
and increased separations 50, 52 from the lever pin 40.
The cable tie tool 20 includes a trigger linkage 54 having a trigger frame 56
the upper
portion of which is supported within the tool handle 24 and pivotally
connected thereto by a
trigger pin 58. The trigger pin 58 extends laterally across the interior
region of the tool
handle 24 and is connected to the inner surface of the grip structure 28.
The trigger fame 56 includes a web structure 60 and left and right flange
structures
62, 64 as shown in Figs. 3, 4, and 5. The web structure 60 has a rectangular
aperture 65. The
flange structures 62 spread upward and downward from the web structure 60, as
shown in
Fig. 4. The web and flange structures 60, 62, 64 may be an integral, unitary
structure and
formed from a single plate 66, an example of which is illustrated in Fig. 6.
The plate 66 is
bent to form the trigger frame 56. The trigger frame 56 is oriented relative
to the grip
structure 28 such that the web structure 60 is to the front of the flange
structures 62, 64. The
8
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
upper ends of the flange structures 62, 64 are hung from the trigger pin 58 to
provide for
pivoting of the trigger frame 56 in the forward and rearward direction
relative to the tool
handle 24.
The trigger frame 56 includes left and right slots 68, 70 which are formed in
the left
and right flange structures 62, 64 such that the left and right slots are each
contiguous with
the web structure 60. Also, the trigger frame 56 includes a gear pin 72 which
extends
between the flange structures 62, 64 and is connected thereto. The connection
between the
gear pin 72 and flange structures 62, 64 may provide for rotation of the gear
pin relative
thereto. The trigger frame 56 has semi-circular left and right recesses 74, 76
in the lower
edges of the flange structures 62, 64. The trigger frame 56 includes a guide
pin 78 which
extends between the flange structures 62, 64 and is connected thereto. The
guide pin 78 is to
the rear of the web structure 60, as shown in Figs. 7 and 8.
The trigger linkage 54 includes a push rod 80 having an elongate body 82 and
an
enlarged head 84 which is integral with the rear end of the body. The head 84
is supported
between the levers 38, 39 and pivotally connected thereto by a push rod pin
86. The push rod
pin 86 extends between the near positions 46 of the levers 38, 39 and is
connected thereto.
The push rod pin 86 extends through the head 84 to provide for upward and
downward
pivoting of the push rod 80 relative to the levers 38, 39. Left and right E-
clips 87, 88 are
fastened to the corresponding ends of the push rod pin 86 such that the
respective E-clips are
to the left and right of the corresponding levers 38, 39. The E-clips 87, 88
restrain the push
rod pin 86 from lateral displacement relative to the levers 38, 39 and head
84.
9
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
The body 82 of the push rod 80 extends forwardly from the head 84 into the
interior
of the trigger frame 56 between the flange structures 62, 64. The body 82 has
a slot 89 which
extends through a longitudinal portion thereof, as shown in Figs. 2 and 7. The
slot 89 is
located to the rear of and adjacent to the forward end 90 of the body 82 The
body 82 is
oriented relative to the flange structures 62, 64 such that guide pin 78
extends through the slot
89. The extension of the guide pin 78 through the slot 89 provides vertical
support to the
body 82 and limits the upward and downward pivoting thereof about the push rod
pin 86
relative to the levers 38, 39. The diameter of the guide pin 78 and transverse
dimension of
the slot 89 provide a vertical clearance between the guide pin and slot such
that the
longitudinal position of the guide pin within the slot may change. The guide
pin 78 engages
the forward end of the slot 89 when the trigger frame 56 is pivoted
sufficiently about the
trigger pin 58 in the forward direction. Consequently, the pivoting of the
trigger frame 56 in
the forward direction is limited by the engagement of the guide pin 78 with
the forward end
of the slot 89.
The forward end 90 of the body 82 of the push rod 80 has a reduced cross-
sectional
area and extends through the aperture 65 in the web structure 60. This allows
longitudinal
displacement of the push rod 80 relative to the web structure 60 which, in
turn, allows
forward and rearward pivoting of the trigger frame 56 about the trigger pin 58
relative to the
tool handle 24. The push rod 80 has a shift surface 96 which is forward facing
and located at
the intersection between the body 82 and forward end 80.
The trigger linkage 54 includes a helical drive spring 98 which is supported
on the
push rod 80 in coaxial relation therewith as shown in Figs. 2 and 7. The rear
end of the drive
spring 98 abuts the head 84 of the push rod 80. The front end of the drive
spring 98 abuts the
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
guide pin 78 of the trigger frame 56. Consequently, rearward pivoting of the
trigger frame 56
compresses the drive spring 98 which, in turn, imparts a rearward force to the
head 84 of the
push rod 80. This, in turn, imparts a rearward force to the push rod pin 86
which urges the
levers 38, 39 to pivot about the lever pin 40 in the rearward direction. The
drive spring 98,
when compressed, imparts a forward force against the guide pin 78 which, in
the absence of a
sufficiently large opposing force applied to the trigger frame 56, urges the
guide pin in the
forward direction to produce corresponding forward pivoting of the trigger
frame.
The trigger linkage 54 includes a shift structure 100 which is supported
within the
trigger frame 56, as shown in Figs. 2, 7, and 11. The shift structure 100
includes a lateral
member 102 and a detent stricture 103 depending therefrom. The shift structure
100
includes three locator projections 104 which extend in the rearward direction
from the lateral
member 102 in integral relation therewith. The locator projections 104 are
positioned
laterally to the left of the detent structure 103. Also, the locator
projections 104 are
positioned laterally relative to one another to define a center projection and
left and right
projections which are located to the left and right of the center projection,
respectively. The
left and right projections of the locator projections 104 each have respective
longitudinal
dimensions which are the same, and the center projection has a longitudinal
dimension which
is greater than the longitudinal dimensions of the left and right projections.
The detent structure 103 is laterally offset between the ends of the lateral
member
102. The shift structure 100 includes left and right knobs 105, 106 which are
fixed to the left
and right ends of the lateral member 102, respectively. The lateral member 102
extends
through the left and right slots 68, 70 such that the left and right knobs
105, 106 are to the left
and right of the left and right flange structures 62, 64, respectively.
11
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
The length of the lateral member 102 is greater than the lateral dimension
between the
outer surfaces of the left and right flange structures 62, 64 to provide for
lateral displacement
of the shift structure 100 relative to the trigger frame 56. The lateral
displacement is limited
by the engagement between the knobs 105, 106, and the outer surfaces of the
left and right
flange structures 62, 64. This limitation results from the knobs 105, 106
being offset from
the axis of the lateral member 102, and the cross-sectional areas of the knobs
being larger
than the area of the slots 68, 70. Consequently, displacement of the shift
structure 100 to the
right relative to the trigger frame 56 is limited by the engagement of the
left knob 105 with
the outer surface of the left flange structure 62. Displacement of the shift
structure 100 to the
left relative to the trigger frame 56 is limited by the engagement of the
right knob 106 with
the outer surface of the right flange structure 64.
The lateral offset of the detent structure 103 provides for the detent
structure to be
closer to the left knob 105 as compared to the right knob 106. Further, the
dimension
between the detent structure 103 and the left knob 105 provides for the detent
structure to be
midway between the left and right flange structures 62, 64 when the left knob
105 is in flush
contact with the outer surface of the left flange structure.
The positioning of the detent structure 103 to the left of the body 82 of the
push rod
80 results in the detent structure not obstructing rearward translation of the
trigger frame 56
relative to the push rod 80 and, consequently, defines the disengaged position
107 of the shift
structure 100. The disengaged position 107 is obtained by laterally displacing
the right knob
106 to the left, relative to the trigger frame 56, to bring the right knob
into flush contact with
the outer surface of the right flange structure 64. This displacement of the
detent structure
12
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
103 to the left of the body 82 is sufficient to establish a lateral clearance
between the detent
structure and body 82 such that the detent structure is to the left thereof.
The lateral clearance
results from the dimension between the detent structure 103 and the right knob
106 and is
sufficient such that the detent structure 103 does not obstruct rearward
translation of the
trigger frame 56 relative to the push rod 80.
The positioning of the detent structure 103 midway between the left and right
flange
structures 62, 64 provides for the detent structure to engage the shift
surface 96 of the push
rod 70. The engagement between detent structure 103 and shift surface 96
results in rearward
pivoting of the trigger frame 56 producing corresponding rearward translation
of the push rod
80. This engagement also results in forward translation of the push rod 80
producing
corresponding forward pivoting of the trigger frame 56. Consequently, the
positioning of the
detent structure 103 midway between the left and right flange structures 62,
64 defines the
engaged position 108 of the shift structure 100. The engaged position 108 is
obtained by
laterally displacing the left knob 105 to the right, relative to the trigger
frame 56, to bring the
left knob into flush contact with the outer surface of the left flange
structure 62. The contact
of the left laiob 105 with the left flange structure 62 results in the detent
structure 103 being
midway between the left flange structure and right flange structures 64 as a
result of the
dimension between the left knob and detent structure.
The trigger linkage 54 includes a gear wheel 114 which extends between the
distant
positions 48 of the left and right levers 38, 39 and is connected thereto. The
connection
between the gear wheel 114 and levers 38, 39 may provide for rotation of the
gear wheel
relative thereto. The gear wheel 114 may be engaged by the gear pin 72 when
the trigger
frame 56 is pivoted in the rearward direction. Following such engagement,
continued
13
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
rearward pivoting of the trigger frame 56 results in rearward pivoting of the
left and right
levers 38, 39 in the rearward direction. Preferably, one or both of the gear
pin 72 and gear
wheel 114 may rotate relative to the trigger frame 56 and levers 38, 39,
respectively, to
reduce possible sliding friction between the surfaces of the gear pin and
wheel which contact
one another.
The trigger linkage 54 includes a lever return spring 115 which is connected
to the
right lever 39 and inner surface of the grip structure 28 for resisting
pivoting of the right lever
from the neutral to tensioned positions 42, 44. This resistance to the
pivoting of the right
lever 39 provides a corresponding resistance to the pivoting of the left lever
38 from the
neutral to tensioned positions 42, 44 as a result of the lateral connections
between the left and
right levers provided by the gear wheel 114 and push rod pin 86.
The trigger linkage 54 includes a trigger housing 116 having a U-shaped rear
section
117 and an elongate front section 118 in depending relation therewith. The
trigger housing
116 is a one-piece unitary structure in which the rear section 117 is integral
with the front
section 118. The upper portion of the rear section 117 is supported within the
tool handle 24
and pivotally connected thereto by the trigger pin 58. The front section 118
has an outer
surface 119 which is grasped by the fingers of the hand of a user when the
tool handle 24 is
grasped by the user. The grasping of the trigger housing 116 by the user, if
sufficiently
forceful, results in pivoting of the trigger housing about the trigger pin 58
in the rearward
direction from the open to closed positions thereof.
The pivoting of the trigger housing 116 in the forward direction is limited by
the
engagement of an upper edge 120 of the front section 118 with the lower
surface of the barrel
14
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
structure 26, which defines the rest position of the trigger housing shown in
Figs. 7, 9, 11,
and 13. The pivoting of the trigger housing 116 in the forward direction
beyond the rest
position may be limited by the engagement between other components of the
cable tie tool,
such as the engagement between the upper ends of the levers 38, 39 and rear
end of the tool
head 35.
The rear section 117 of the trigger housing 116 has a cutout 121 in the lower
end
thereof. The cutout 121 has a lateral cross-section which is U-shaped. The
cutout 121 is
bordered to the front and rear thereof by front and rear edges 122, 123 of the
rear section 117.
The trigger. frame 56, which is also pivotally connected to the tool handle 24
by the trigger
pin 58, is supported within the rear section 117 of the trigger housing 116.
The trigger linkage 54 includes a hand-size adjustment mechanism 125 through
which
the trigger housing 116 is coupled to the trigger frame 56. The adjustment
mechanism 125
includes an adjustment rod 126 having an elongate body 128 and an enlarged
head 130 which
is integral with the forward end of the body. The adjustment rod 126 has a
left stop pin 132
and a right stop pin each of which extends laterally from the lower surface of
the head 130 in
integral relation therewith. The head 130 is supported between the left and
right flange
structures 62, 64 and pivotally connected thereto by an adjustment pin 134.
Sufficient
pivoting of the body 128 relative to the trigger frame 56 in the upward
direction results in the
left stop pin 132 and right stop pin each becoming lodged in the left and
right recesses 74, 76
which, consequently, limits the degree of such upward pivoting of the
adjustment rod 126.
The body 128 of the adjustment rod 126 is externally threaded. The adjustment
mechanism 125 includes an adjustment wheel 136 which is internally threaded to
provide for
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
the wheel to be screwed onto the externally threaded body 128. The threaded
engagement
between the wheel 136 and body 128 results in rotation of the wheel relative
to the body 128
results in longitudinal translation of the wheel relative to the body. The
adjustment wheel
136 has an outer surface which is roughened or uneven to facilitate gripping
thereof by the
user.
The trigger housing 116 is arranged relative to the adjustment mechanism 125
for the
location thereof within the rear section 117. The arrangement further provides
for access
through the cutout 121 to the adjustment wheel 136 and, more specifically, to
the bottom and
side portions of the outer surface of the wheel for gripping thereof by a
finger or thumb of the
hand of the user for rotation of the wheel.
The adjustment wheel 136 has an outer diameter which is sufficiently large to
extend
downwardly into the cutout 121. Consequently, forward and rearward translation
of the
wheel 136 relative to the body 128 of the adjustment rod 126 results in
engagement of the
wheel with the respective font and rear edges 122, 123 of the rear section
117. Such
engagement causes corresponding forward or rearward pivoting of the trigger
housing 116
relative to the trigger frame 56.
The trigger linkage 54 includes an elongate locator spring 138 for maintaining
the
shift structure 100 in the disengaged or engaged positions 107, 108. The
locator spring 138 is
located between the left and right flange structures 62, 64 and to the rear of
the web structure
60. The upper end of the locator spring 138 is formed into an upper hook 140
which extends
in the leftward direction. The lower end of the locator spring 138 is formed
into a lower hook
142 which extends in the forward direction. The upper hook 140 overhangs the
upper edge
16
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
of the left flange structure 62 and the lower hook 142 extends around the
lower surface of the
head 130 of the adjustment rod 126 such that the locator spring is supported
by the head of
the adjustment rod and the left flange structure. The locator spring 138 has
an intermediate
portion 144 between the upper and lower hooks 140, 142.
The locator spring 138 is positioned laterally relative to the shift structure
100 such
that the intermediate portion 144 extends between the left and center
projections of the
locator projections 104 when the shift structure is laterally positioned in
the disengaged
position 107. The location of the intermediate portion 144 between the left
and center
projections of the locator projections 104 maintains the shift structure 100
in the disengaged
position 107 by providing resistance to lateral translation of the lateral
member 102. The
lateral position of the locator spring 138 relative to the shift structure 100
further provides for
the intermediate portion 144 to extend between the center and right
projections of the locator
projections 104 when the shift structure is laterally positioned in the
engaged position 108.
The location of the intermediate portion 144 between the center and right
projections of the
locator projections 104 maintains the shift structure 100 in the engaged
position 108 by
providing resistance to lateral translation of the lateral member 102. The
increased
longitudinal dimension of the center projection of the locator projections 104
provides further
resistance to lateral translation of the shift structure 100 between the
disengaged and engaged
positions 107, 108.
In operation, the hand-size adjustment mechanism 125 is manipulated to adjust
the
separation in the forward direction between the front surface of the trigger
housing 116 and
the rear surface of the grip structure 28 to fit the size of the hand of the
user of the cable tie
tool 20. This is done by rotating the adjustment wheel 136 to cause forward or
rearward
17
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
translation thereof relative to the body 128 of the adjustment rod 126.
Forward translation of
the wheel 136 relative to the body 128 causes engagement thereof with the
front edge 122 of
the rear section 117. Continued forward translation of the wheel 136 results
in corresponding
forward pivoting of the rear section 117 and, consequently, forward pivoting
of the trigger
housing 116 relative to the trigger frame 56. The forward pivoting increases
the separation in
the forward direction between the front surface of the trigger housing 116 and
the rear surface
of the grip structure 28. Examples of the adjustment mechanism 125 manipulated
to provide
the increased separation are shown in Figs. 7, 8, 11, and 12. Increasing the
separation
between the trigger housing 116 and grip structure 28 is normally desirable
when the size of
the hand of the user of the cable tie tool 20 is relatively large.
When the hand of the user of the cable tie tool 20 is relatively small, the
hand-size
adjustment mechanism 125 is manipulated to translate the wheel 136 in the
rearward
direction relative to the body 128. Consequently, the wheel 136 engages the
rear edge 123 of
the rear section 117. Continued rearward translation of the wheel 136 results
in
corresponding rearward pivoting of the rear section 117 and, consequently,
rearward pivoting
of the trigger housing 116 relative to the trigger frame 56. The rearward
pivoting decreases
the separation in the rearward direction between the front surface of the
trigger housing 116
and the rear surface of the grip structure 28. Examples of the adjustment
mechanism 125
manipulated to provide the decreased separation are shown in Figs. 9, 10, 13,
and 14.
Decreasing the separation between the trigger housing 116 and grip structure
28 is normally
desirable when the size of the hand of the user of the cable tie tool 20 is
relatively small.
The trigger linkage 54 may be shifted between automatic gear operation or
fixed gear
operation by positioning the shift structure 100 in the disengaged or engaged
positions 107,
18
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
108, respectively. More specifically, the trigger linkage 54 is shifted to the
automatic gear
operation by moving the shift structure 100 to the disengaged position 107
which is obtained
by pushing the right knob 106 of the shift structure 100 laterally to the left
into abutment with
the outer surface of the right flange structure 64. The right knob 106 is
pushed with sufficient
force to overcome the resistance of the locator spring 138 to the
corresponding lateral
translation of the locator projections 104. The moving of the right knob 106
into abutment
with the right flange structure 64 results in a corresponding displacement of
the detent
structure 103 laterally to the left which is sufficient to establish the
lateral clearance between
the detent structure and body 82 of the push rod 80. When the shift structure
100 is in the
disengaged position 107, the detent structure 103 does not obstruct rearward
translation of the
trigger frame 56 relative to the push rod 80. Examples of the shift structure
100 in the
disengaged position 107 and, consequently, the trigger linkage 54 configured
for automatic
gear operation are shown in Figs. 7, 8, 9, and 10.
The user grasps the cable tie tool 20 such that the outer surface 30 of the
grip structure
28 is grasped by the palm of the hand of a user and the fingers of the hand
wrap around the
outer surface 119 of the front section 118 of the trigger housing 116. The
hand is then
forcibly closed to draw the trigger housing 116 in the rearward direction
toward the grip
structure 28 to pivot the trigger housing from the open to closed positions
thereof.
Consequently, the trigger housing 116 is pivoted in the rearward direction
which causes the
front edge 122 of the rear section 117 to drive the adjustment wheel 136 in
the rearward
direction. This, in turn, causes the wheel 136 to pull the adjustment rod 126
in the rearward
direction which results in pivoting of the trigger frame 56 in the rearward
direction.
19
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
Pivoting of the trigger frame 56 in the rearward direction causes the guide
pin 78 to be
driven in the rearward direction which results in the guide pin translating
through the slot 89
in the push rod 80 and displacing the front end of the drive spring 98 in the
rearward
direction. This results in compression of the drive spring 98, translation of
the rear end of the
drive spring 98 in the rearward direction, or both. Rearward translation of
the rear end of the
drive spring 98 causes corresponding rearward displacement of the head 84 of
the push rod
80. Rearward displacement of the head 84 results in pivoting of the left and
right levers 38,
39 in the rearward direction from the neutral to the tensioned positions 42,
44. Consequently,
the coupling between the trigger frame 56 and levers 38, 39 is provided
through the near
positions 46. Also, the pivoting of the left and right levers 38, 39 in the
rearward direction
results in the compression of the lever return spring 115.
The rearward pivoting of the levers 38, 39, as a result of the coupling
thereof to the
tool head 35, causes in an increase in the tension in the cable tie 22 which
is secured thereto.
Additionally, when the compression of the drive spring 98 is sufficiently
limited, the
rearward pivoting of the levers 38, 39 results in rearward displacement of the
gear wheel 114
relative to the gear pin 72 causing rearward separation of the gear wheel from
the gear pin.
Typically, as the tension in the cable tie 22 is increased, further increases
in the
tension thereof are resisted by the cable tie. This resistance is transmitted
through the trigger
linkage 54 to the trigger housing 116 which results in increasingly greater
force being
required to be applied to the outer surface 119 of the front section 118 by
the fingers of the
user for continued pivoting of the trigger housing in the rearward direction.
Application of
increasingly greater force to the trigger housing 116 further compresses the
drive spring 98
between the guide pin 78 and head 84 of the push rod 80.
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
Compression of the drive spring 98 results in the separation between the gear
wheel
114 and the gear pin 72 decreasing. When the compression of the drive spring
98 is
sufficient, the gear pin 72 contacts the gear wheel 114 such that the trigger
frame 56 drives
the rearward pivoting of the levers 38, 39 through the gear pin 72 and gear
wheel rather than
through the drive spring 98 and push rod pin 86, which provides the coupling
before the
engagement between the gear pin and wheel. Consequently, the coupling between
the trigger
frame 56 and levers 38, 39 is provided through the distant positions 48.
The transfer of the coupling from the near positions 46 to the distant
positions 48
results in an increase in the force applied to the tool head 35 by the
rearward pivoting of the
levers 38, 39 for a uniform force applied to the trigger housing 116 for
pivoting thereof in the
rearward direction from the open to closed positions. The increase in the
force applied to the
tool head 35 results from the increased separation 52 between the gear wheel
114 and lever
pin 40 as compared to the reduced separation 50 between the push rod pin 86
and lever pin.
Pivoting of the trigger housing 116 in the rearward direction, after the
engagement of the gear
pin 72 with the gear wheel 114 results in the increased force being applied to
the tool head 35
and, consequently, increased tensioning of the cable tie 22.
When the tension in the cable tie 22 is sufficiently increased, the hand of
the user
which grips the grip structure 28 and trigger housing 116 are relaxed. This
results in the lever
return spring 115 expanding which forcibly pivots the left and right levers
38, 39 in the
forward direction. Additionally, the drive spring 98 expands which forcibly
displaces the
guide pin 78 in the forward direction relative to the push rod 80.
Consequently, the guide pin
78 pivots the trigger frame 56 in the forward direction which, in turn, pivots
the trigger
21
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
housing 116 in the forward direction. If the hand of the user is sufficiently
relaxed, the
trigger housing 116 may be allowed to pivot sufficiently in the forward
direction such that the
levers 38, 39 are returned to the neutral positions 42 and the trigger housing
116 is returned to
the rest position thereof, as shown in Figs. 7 and 9.
The trigger linkage 54 is shifted from the automatic gear operation to the
fixed gear
operation by completely releasing the trigger housing 116 to allow the lever
return spring 115
to pivot the levers 38, 39 in the forward direction to the neutral positions
42 and the drive
spring 98 to pivot the trigger frame 56 in the forward direction such that the
trigger housing
116 is returned to the rest position thereof. With the shift structure 100 in
the disengaged
position 107, this forward pivoting results in corresponding displacement of
the body 82 of
the push rod 70 in the forward direction such that the shift surface 96 is to
the rear of the
detent structure 103 by a slightly dimension. With the body 82 being held in
this position
relative to the decent structure 103, the left knob 105 of the shift structure
100 is displaced
laterally to the right into abutment with the outer surface of the left flange
structure 62. The
left knob 105 is displaced with sufficient force to overcome the resistance of
the locator
spring 138 to the corresponding lateral translation of the locator projections
104. The moving
of the left knob 105 into abutment with the left flange structure 62 results
in a corresponding
displacement of the detent structure 103 laterally to the right to a position
midway between
the left and right flange structures 62, 64 such that the detent structure is
directly to the front
of the shift surface 96 in the in the engaged position 108. When the shift
structure 100 is in
the engaged position 108, the detent structure 103 obstructs rearward
translation of trigger
frame 56 relative to the push rod 80. Examples of the shift structure 100 in
the engaged
position 108 and, consequently, the trigger linkage 54 configured for fixed
gear operation are
shown in Figs. 11, 12, 13, and 14.
22
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
The user grasps the cable tie tool 20 such that the outer surface 30 of the
grip structure
28 is grasped by the palm of the hand of a user and the fingers of the hand
wrap around the
outer surface 119 of the front section 118 of the trigger housing 116. The
hand is then
forcibly closed to draw the trigger housing 116 in the rearward direction
toward the grip
structure 28 to pivot the trigger housing from the open to closed positions
thereof.
Consequently, the trigger housing 116 is pivoted in the rearward direction
which causes the
front edge 122 of the rear section 117 to drive the adjustment wheel 136 in
the rearward
direction. This, in turn, causes the wheel 136 to pull the adjustment rod 126
in the rearward
direction which results in pivoting of the trigger frame 56 in the rearward
direction.
Pivoting of the trigger frame 56 in the rearward direction causes the web
structure 60
to drive the shift structure 100 in the rearward direction such that the
detent structure 103
contacts the shift surface 96 of the push rod 80. Continued pivoting of the
trigger frame 56 in
the rearward direction causes the detent structure 103 to forcibly translate
the body 82 of the
push rod 80 in the rearward direction. This translation of the push rod 80 is
transmitted
through the push rod pin 86 to the left and right levers 38, 39 to cause
pivoting thereof in the
rearward direction from the neutral position 42 to the tensioned position 44.
The pivoting of
the left and right levers 38, 39 in the rearward direction results in the
compression of the lever
return spring 115. Also, the rearward pivoting of the levers 38, 39, as a
result of the coupling
thereof to the tool head 35, causes in an increase in the tension in the cable
tie 22 which is
secured thereto.
The coupling between the trigger frame 56 and levers 38, 39 is provided by the
push
rod 80 and push rod pin 86 throughout the entire pivoting of the trigger
frame. Consequently,
the coupling between the trigger frame 56 and levers 38, 39 is provided
through the near
23
CA 02560299 2006-09-19
WO 2005/089978 PCT/US2005/009319
positions 46 and does not transfer to the distant position 48, in contrast to
the automatic gear
operation. As a result, the force applied to the tool head 35 by the rearward
pivoting of the
levers 38, 39 results from the coupling through the distant position 48 for
the entire pivoting
of the trigger housing 116 in the rearward direction from the open to closed
positions. The
coupling the fixed gear operation does not utilize the drive spring 98, also
in contrast to the
automatic gear operation.
When the tension in the cable tie 22 is sufficiently increased, the hand of
the user
which grips the grip structure 28 and trigger housing 116 are relaxed. This
results in the lever
return spring 115 expanding which forcibly pivots the left and right levers
38, 39 in the
forward direction which drive the push rod pin 86 in the forward direction.
Forward
translation of the push rod pin 86 drives the push rod 80 and detent structure
103 in the
forward direction which, in turn, drives the web structure 60 in the forward
direction.
Consequently, the trigger frame 56 pivots in the forward direction which, in
turn, pivots the
trigger housing 116 in the forward direction. If the hand of the user is
sufficiently relaxed,
the trigger housing 116 may be allowed to pivot sufficiently in the forward
direction such that
the levers 38, 39 are returned to the neutral positions 42 and the trigger
housing 116 is
returned to the rest position thereof, as shown in Figs. 11 and 13.
While the invention has been described by reference to certain preferred
embodiments, it should be understood that numerous changes could be made
within the spirit
and scope of the inventive concept described. Accordingly, it is intended that
the invention
not be limited to the disclosed embodiments, but that it have the full scope
permitted by the
language of the following claims.
24
