Note: Descriptions are shown in the official language in which they were submitted.
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ADJUSTABLE PLIER
Field of the Invention
The present invention relates to a pair of pliers, and more precisely to
pliers with a
jaw opening which can be adjusted quickly.
Description of the Prior art
Traditional pliers have two intersecting plier arms which are rotatable around
a pivot
in an intersection region for gripping objects. Jaws for gripping objects are
formed
above the intersection region and handles for holding are below the
intersection
region. However, the jaw opening of the pliers is fixed, so the size range of
the
gripped objects is limited.
Therefore, US Patent No.5845551 discloses a pair of pliers with an adjustable
jaw
opening, wherein one plier arm is formed with a hollow elongated rack slot in
the
middle of the intersection region and the rack slot is profiled on its inner
flanks, the
profiling being a saw-tooth profiling. The other plier arm is displaceable
stepwise
along the teeth on the inner flanks of the rack slot, and can be fixed to each
tooth; thus
the span between the jaws can be adjusted.
However, the adjustment of the pliers is both-way, which is to say that the
pivot in the
intersection region has an adjusting switch. When the switch is on, the two
plier arms
can move relatively. When the switch is off, the positions of the two plier
arms are
fixed relatively to be available for use. The drawback of this design is
inconvenience
in use. In use, firstly turn on the switch, and keep it on, then enlarge the
span between
the jaws to being larger than the size of the gripped object, and then
gradually narrow
the span to the exact size of the object to grip it only if the switch is kept
on. Both
processes of enlarging and narrowing the span require keeping the switch on to
adjust
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,
the span between the jaws. Therefore, it is very inconvenient for users, so
further
improvement is needed in order that not only holding the switch all the time
is no
more required, but also the design of the switch is more simple and
convenient.
Summary of the Invention
The objective of the present invention is to provide a pair of pliers, wherein
only
one-way adjustment of the jaw opening needs an adjusting switch while the
adjustment of the jaw opening in the other way does not need any switch, thus
stabilizing the plier jaws on the object to be gripped.
Another objective of the present invention is to provide a pair of pliers with
an
adjustable jaw opening, wherein the adjusting switch is designed simple and
convenient to use.
A pair of adjustable pliers comprises a first handle having a first gripping
part
arranged at a front end thereof and a second handle having a second gripping
part
arranged at a front end thereof, the first gripping part and the second
gripping part
forming a jaw span, the first handle and the second handle being arranged in
an
intersectional manner and relatively fixed via a connecting mechanism, wherein
the
second handle has an elongated rack slot at a position of the connecting
mechanism,
and the rack slot is provided with a toothed rack on an inner side part
thereof. The
connecting mechanism comprises a positioning snap piece arranged inside the
rack
slot and a link mechanism connected with the positioning snap piece, the
positioning
snap piece has lateral teeth which are engaged with the toothed rack on the
rack slot,
and the link mechanism is provided to drive the positioning snap piece to
rotate and
disengage the lateral teeth on the positioning snap piece from the toothed
rack. Thus
the first handle can move relative to the second handle along the rack slot
through the
movement of the connecting mechanism. The link mechanism comprises a trigger
shaft connected with the positioning snap piece, and the trigger shaft has a
trigger part
thereon.
2
,
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Further, teeth of the toothed rack are one-way ratchet teeth.
Further, the trigger shaft is arranged in a through-hole of the positioning
snap piece,
and the trigger part is a pressing part of the trigger shaft extending to the
outer side of
the surface of the first handle.
Further, the link mechanism further comprises a roller pin arranged on the
trigger
shaft at a position of the positioning snap piece, one end of the roller pin
extending
out from the lateral of the trigger shaft, the other end thereof extending
onto an
inclined plane of the positioning snap piece.
Further, the inclined plane is located at an upper side of the through-hole of
the
positioning snap piece, and the lateral teeth of the positioning snap piece
are located
at one side of the lower part under the through-hole of the positioning snap
piece.
Further, the inclined plane gradually descends from one side of the lateral
teeth of the
positioning snap piece to the other side thereof.
Further, the roller pin can be fixedly connected or integrated with the
trigger shaft.
Further, one end of the roller pin extends into a lateral hole of the trigger
shaft, and is
fixedly connected with the trigger shaft.
Further, a shape of a cross-section of the trigger shaft is a notched circle.
Further, the link mechanism further comprises a sheet body with a hollow hole,
which
makes it sheathed on the trigger shaft, and the shape of the hollow hole fits
that of the
cross-section of the trigger shaft.
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Further, a lateral wall of the first handle is provided with a lateral hole at
a position of
the connecting mechanism, and the lateral hole allows a corresponding region
of the
second handle to pass through, forming a first part of the first handle
located over the
second handle and a second part of the first handle located beneath the second
handle,
wherein the trigger shaft passes through the first part of the first handle,
and then
passes through the rack slot of the second handle, and further passes through
the
second part of the first handle.
Further, a first end of the trigger shaft extends to the first part at one
side of the first
handle, and a second end extends to the second part at the other side of the
first handle,
wherein the trigger part is located at the outer side of the first part, and
is fixed with
the trigger shaft via a fixing element at the outer side of the second part.
Further, the positioning snap piece is provided with a fixing part and an
elastic piece
at the other side, opposite to the lateral teeth, of the lower part under the
through-hole,
and the elastic piece is connected onto the fixing part and propped against
the second
handle.
Further, the fixing part is a spring hole, and the elastic piece is a spring
which is
arranged inside the spring hole.
Further, the planes at the inner side of the first gripping part and the
second gripping
part are intersected at an angle, a gap is formed between the first gripping
part and the
second gripping part, and the edges of the inner sides of the first gripping
part and the
second gripping part are provided with stripes to facilitate gripping and
engaging.
Further, the first gripping part or the second gripping part can be integrated
with the
first handle or the second handle, or can be connected to the handles via
connecting
means as well.
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Further, the sheet body is provided between the positioning snap piece and the
fixing
element.
Further, the sheet body is located inside the rack slot, and an outer edge of
the sheet
body is square, fitting an inner edge of the rack slot.
Further, the link mechanism further comprises a pressure spring which is
arranged
inside a depression of the outer side of the first part of the first handle,
contacting the
trigger part.
Another shape of jaws is that the first gripping part and the second gripping
part are
configured as planes, and the edges of the inner sides are provided with
stripes. The
planes at the inner sides of the first gripping part and the second gripping
part are
parallel.
The present invention has the advantages that the right handle can be directly
pushed
to achieve the quick one-way adjustment, which is convenient and saves effort
compared to the ordinary water pump pliers that need two-handed adjustment.
The
button can be integrated with the roller pin, which can save the processing
cost and
improve the production efficiency.
The novel shape of jaws of the present invention is also brought into better
fitness
with that of a hexagon nut. Compared to ordinary water pump pliers (which do
not fit
well with the hexagon nut in larger size), the present product can preferably
fit with
the hexagon nuts in all sizes within a gear range. The quick one-way gear
adjustment
is achieved, which is convenient and saves effort compared to the ordinary
water
pump pliers that need two-handed adjustment. By adoption of the present
structure,
the engagement between the teeth of the product is more stable, which is more
convenient in operation.
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Brief Description of the Drawings
Figure 1 is a schematic diagram according to a preferable embodiment of the
present
invention.
Figure 2 is an exploded view according to a preferable embodiment of the
present
invention.
Figure 3 is an exploded view according to a preferable embodiment of the
present
invention from another angle.
Figure 4 is an exploded view of the positioning snap piece according to a
preferable
embodiment of the present invention.
Figure 5 is a composition diagram of the positioning snap piece according to a
preferable embodiment of the present invention.
Figure 6 is a perspective view of the trigger shaft according to a preferable
embodiment of the present invention.
Figure 7 is a sectional view according to a preferable embodiment of the
present
invention, wherein the trigger shaft is in an initial state.
Figure 8 is a sectional view according to a preferable embodiment of the
present
invention, wherein the trigger shaft is in a pressed state.
Figure 9 is a schematic diagram of the jaw opening according to a preferable
embodiment of the present invention.
Figure 10 is a schematic diagram of the jaw gripping objects according to a
preferable
embodiment of the present invention.
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Figure 11 is a side view according to a preferable embodiment of the present
invention, wherein the lateral teeth of the positioning snap piece are in an
engaging
state.
Figure 12 is a side view according to a preferable embodiment of the present
invention, wherein the lateral teeth of the positioning snap piece are in a
disengaging
state.
Figure 13 is a schematic diagram according to a second embodiment of the
present
invention.
Figure 14 is an exploded view according to a second embodiment of the present
invention.
Figure 15 is an exploded view according to a second embodiment of the present
invention from another angle.
Figure 16 is a local enlarged exploded view according to a second embodiment
of the
present invention.
Detailed Description of the Preferred Embodiments
As shown in Figures 1-12, the present invention provides a preferable
embodiment. A
pair of adjustable pliers comprises a first handle 5 having a first gripping
part 2
arranged at the front end thereof and a second handle 9 having a second
gripping part
1 arranged at the front end thereof. The first gripping part 2 and the second
gripping
part 1 form a jaw span, and the first handle and the second handle are
arranged in an
intersecting manner and relatively fixed via a connecting mechanism, wherein
the
second handle has an elongated rack slot 91 at the position of the connecting
mechanism and the rack slot 91 is provided with a toothed rack 92 on its inner
side
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part. The connecting mechanism comprises a positioning snap piece 6 arranged
inside
the rack slot 91 and a link mechanism connected with the positioning snap
piece 6, the
positioning snap piece 6 has lateral teeth 61 which are engaged with the
toothed rack
92 profiled on the rack slot 91. The link mechanism drives the positioning
snap piece
6 to rotate and disengages from the toothed rack 92. Thus the first handle 5
can move
relative to the second handle 9 along the rack slot 91 through the movement of
the
connecting mechanism to change jaw opening, wherein the teeth on the toothed
rack
92 are one-way ratchet teeth, i.e. the teeth are all oblique toward one
direction,
inclining toward the direction of the arrow as shown in Figure 1. In this way,
when a
force is exerted in a direction opposite to the inclining teeth, i.e. the
opposite direction
of the arrow, due to the barbs between the toothed rack 92 and the positioning
snap
piece 6, an external force is required to separate them to enable the
positioning snap
piece 6 to slide in the rack slot 91. While in the inclining direction of the
teeth, i.e. the
direction of the arrow, the toothed rack 92 can drive the positioning snap
piece 6 to
overcome the elastic force and automatically disengage from the teeth on the
toothed
rack 92 without any external force, and thus achieving quick one-way sliding.
Specifically, the meaning of one-way ratchet teeth is that the teeth of the
toothed rack
92 extend obliquely upward from the edge of the slot, inclining toward the
arrow
direction beside the rack slot as shown in Figure 1. When the jaw opening
needs to be
enlarged, i.e. the first handle 5 is pulled down from the top of the rack slot
91 (i.e.
moving toward the opposite direction of the arrow), a trigger part 71 of the
link
mechanism is needed to disengage the positioning snap piece 6 from the toothed
rack
92, and when the first handle 5 is pulled up from the lower part of the rack
slot 91 (i.e.
moving toward the direction of the arrow), because of the one-way ratchet
teeth, even
if the positioning snap piece 6 and toothed rack 92 are in engagement, the
positioning
snap piece 6 can still move along the rack slot freely. Thus, in the enlarged
status of
the jaw opening, put the object into the opening, and then shrink the opening
just to
match the size of the object to grip it.
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The adjustable pliers can be water pump pliers, pipe pliers or other pliers,
wherein the
planes at the inner side of the first gripping part and the second gripping
part are
intersected at an angle, and a gap is formed between the first gripping part
and the
second gripping part. The shape of such jaw span is brought into better
fitness with
that of a hexagon nut. Compared to ordinary water pump pliers (which do not
fit well
with the hexagon nut in larger size), the present product can preferably fit
with the
hexagon nuts in all sizes within a gear range. The first gripping part 2 and
the second
gripping part 1 can be integrated with the first handle 5 and the second
handle 9
respectively, or can be connected to the handles via connecting means as well.
The position of the first handle 5 and that of the link mechanism are
relatively fixed.
The link mechanism comprises a trigger shaft 7 connected with the positioning
snap
piece 6, and the trigger shaft 7 has a trigger part 71 thereon. The trigger
part 71 is a
pressing part of the trigger shaft 7 extending to the outer side of the
surface of the first
handle 5, which is convenient to trigger the trigger shaft 7 to move through
the trigger
part 71 when hand-holding the pliers body, thus adjusting the jaw opening at
any time.
The trigger part 71 drives the trigger shaft 7 to move, and the trigger shaft
7 drives the
positioning snap piece 6 to rotate, thus disengaging from the toothed rack 92
on the
rack slot 91 and enabling the first handle 5 to move relatively to the second
handle 9
in a direction opposite to the arrow, which makes the jaw opening become
larger.
The first handle 5 is provided with a first through-hole in the region of the
trigger
shaft 7, and the trigger shaft 7 passes through the first through-hole and
then passes
through the rack slot 91 of the second handle 9 to relatively fix the first
handle 5 and
the second handle 9. Further, the first handle 5 is provided with a lateral
hole 51 on its
lateral wall in the region of the connecting mechanism, which allows the
corresponding region of the second handle 9 to pass through, forming a first
part 52 of
the first handle 5 located over the second handle 9 and a second part 53 of
the first
handle located beneath the second handle, wherein the trigger shaft 7 passes
through
the first part of the first handle 5, then through the rack slot 91 of the
second handle,
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and further through the second part of the first handle 5. The positioning
snap piece 6
is located inside the rack slot 91 of the second handle 9, engaging with the
toothed
rack 92.
Specifically, in the present embodiment, the trigger shaft 7 is arranged in
the
through-hole of the positioning snap piece 6. A first end of the trigger shaft
7 extends
to the first part at one side of the first handle 5, and a second end extends
to the
second part at the other side of the first handle 5, being connected or
integrated with
the trigger part 71 which has the fixing function as well at the outer side of
the first
part, and being fixed with the trigger shaft 7 via a fixing element 10 at the
outer side
of the second part. The fixing element may be a cap body which fixes the
trigger shaft
7 at the second part at the other side of the first handle 5, or may be a nut
that is
rotated onto rotating threads at the other end of the trigger shaft 7, thus
fixing the
trigger shaft 7. The trigger shaft 7 and the trigger part 71 as well as the
cap body can
move along with the first handle along the rack slot 91 of the second handle
9.
The link mechanism further comprises a roller pin 72 which is arranged on the
trigger
shaft 7 at the position of the positioning snap piece 6. One end of the roller
pin 72
extends out from the lateral of the trigger shaft 7, and the other end of the
roller pin 72
extends onto an inclined plane 64 of the positioning snap piece 6. The roller
pin 72
can be fixedly connected or integrated with the trigger shaft 7. In the
present
embodiment, one end of the roller pin 72 extends into the lateral hole 76 of
the trigger
shaft 7, and is fixedly connected with the trigger shaft 7. The other end of
the roller
pin 72 extends to the inclined plane 64 on the positioning snap piece 6. The
inclined
plane 64 is located at the upper side of the through-hole of the positioning
snap piece
6, and the lateral teeth 61 of the positioning snap piece 6 are located at the
lower side
of the through-hole of the positioning snap piece 6. The inclined plane 64
gradually
descends from one side of the lateral teeth 61 of the positioning snap piece 6
to the
other side thereof. In this way, when pressure is exerted to the trigger part
71, the
trigger shaft 7 moves downwards, and the roller pin 72 moves downwards along
with
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the trigger shaft 7, which forces the positioning snap piece 6 to rotate
toward the
higher side of the inclined plane 64 at the upper side part of the through-
hole, thus
enabling the lower part of the inclined plane 64 on the positioning snap piece
6 to
accommodate the roller pin 72. Meanwhile, the positioning snap piece 6 moves
in an
opposite direction taking the trigger shaft 7 as axis at the lower side part
of the
through-hole, i.e., the lateral teeth 61 on the positioning snap piece 6 are
separated
from the toothed rack 92 on the rack slot 91, thus the first handle 5 can move
in a
direction opposite to the arrow along the second handle.
Further, the shape of the cross-section of the trigger shaft 7 is noncircular,
specifically
a notched circle in the present embodiment. The link mechanism of the present
invention further comprises a sheet body 74 with a hollow hole 75, which makes
it
sheathed on the trigger shaft 7. The shape of the hollow hole fits that of the
cross-section of the trigger shaft 7. In this way, when the trigger shaft 7
receives a
pressing force, the sheet body 74 can limit the rotation of the trigger shaft
7, thus
forcing the positioning snap piece 6 to rotate around the trigger shaft 7. The
lateral
hole of the trigger shaft 7 is located at the circular slot of the cross-
section, and one
end of the roller pin 72 is also arranged in a hole at the lateral slot of the
trigger shaft
7. Specifically, the sheet body 74 is arranged at the rear of the positioning
snap piece
6, located between the positioning snap piece 6 and the fixing element, i.e.,
the cap
body, and is arranged inside the rack slot 91 together with the positioning
snap piece 6.
An outer edge of the sheet body 74 is square, fitting with an inner edge of
the rack
slot 91, without causing rotation around the trigger shaft 7, thus limiting
the rotation
of the trigger shaft 7, and fixing the trigger shaft 7 in the direction of
rotation.
As described above, the lateral teeth 61 of the positioning snap piece 6 are
located at
one side of the lower part under the through-hole of the positioning snap
piece 6, the
positioning snap piece 6 is provided with a fixing part 62 and an elastic
piece 63 at the
other side, opposite to the lateral teeth 61, of the lower part under the
through-hole of
the positioning snap piece 6, and the elastic piece 63 is connected onto the
fixing part
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62 and propped against the second handle 9. Specifically, the fixing part 62
may be a
spring hole, the elastic piece 63 is specifically a spring which is arranged
in the spring
hole and propped against the second handle 9. In this way, when the trigger
part 71 is
released, due to the action of the spring, the lateral teeth 61 of the
positioning snap
piece 6 can restore the engagement with the teeth on the toothed rack 92, thus
being
available for use.
The link mechanism further comprises an elastic element, specifically a taper
spring
73 arranged in the depression at the outer side of the first part of the first
handle 5,
and contacting the inner side of the trigger part 71. In this way, when no
pressure is
exerted to the trigger part 71, the taper spring can jack up the trigger part
71, and
drive the link mechanism to restore to the home position, and to the initial
state. As
shown in Figure 6, a peripheral surface of the trigger part 71 in the present
preferable
embodiment is circular. In other embodiments, the peripheral surface of the
trigger
part 71 can also be a shape suitable for installation such as a polygon.
The structural function of the preferable embodiment of the present invention
is
achieved as follow. As shown in Figure 8, pressure is applied on the trigger
shaft 7,
which drives the roller pin 72 to move in a direction of the applied force.
When the
roller pin 72 contacts the inclined plane 64 of the positioning snap piece 6,
the
positioning snap piece 6 rotates around the axis of the trigger shaft 7 under
the action
of the force, and the positioning snap piece 6 and the lateral teeth 61 are in
a
non-engaging state, thus achieving quick gear shifting, wherein a bottom guide
sheet
74 limits the rotation of the trigger shaft 7, thus counteracting the
counterforce of the
inclined plane 64 against the roller pin 72. The pressure at the trigger shaft
7 is
removed, and under the action of the elastic piece 63 and the taper spring 73,
the
whole structure resets to the initial state as shown in Figure 7.
In the present embodiment, the right handle can be directly pushed to achieve
the
quick one-way adjustment from Figure 9 to Figure 10 (a parallel jaw span a
needs to
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be greater than a parallel jaw span b), which is convenient and saves effort
compared
to the ordinary water pump pliers that need two-handed adjustment. The button
can be
integrated with the roller pin, which can save the processing cost and improve
the
production efficiency.
As shown in Figures 11-12, the jaws of the present embodiment can be adjusted
as
parallel planes, i.e., the inner sides of the first gripping part and the
second gripping
part are configured as planes, and the edges of the inner sides are provided
with
stripes. The planes at the inner sides of the first gripping part and the
second gripping
part are parallel. The shape of the jaw span is also brought into fitness with
that of a
hexagon nut. Compared to ordinary water pump pliers (which do not fit well
with the
hexagon nut in larger size), the present product can preferably fit with the
hexagon
nuts in all sizes within a gear range. The adjustable pliers of the present
invention can
achieve quick one-way gear adjustment, which is convenient and saves effort
compared to the ordinary water pump pliers that need two-handed adjustment. By
adoption of the present structure, the engagement between the teeth of the
product is
more stable, which is more convenient in operation.
As shown in Figures 13-16, the present invention provides a second embodiment.
A
pair of adjustable pliers comprises a first handle 5 having a first gripping
part 2
arranged at the front end thereof and a second handle 9 having a second
gripping part
1 arranged at the front end thereof. The first gripping part 2 and the second
gripping
part 1 form a jaw span, and the first handle and the second handle are
arranged in an
intersecting manner and relatively fixed via a connecting mechanism, wherein
the
second handle is provided with an elongated rack slot 91 in the region of the
connecting mechanism and the rack slot 91 is provided with a toothed rack 92
on its
inside flank. The connecting mechanism comprises a toothed block 3, which is
arranged inside the rack slot 91 and engaged with the toothed rack 92 on the
rack slot
91, and a link mechanism connected with the toothed block 3 to drive it to
rotate and
disengage from the rack slot 91. Thus the first handle 5 is able to move
relative to the
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second handle 9 along the rack slot 91 through the movement of the connecting
mechanisms to change the size of the opening, wherein the teeth on the toothed
rack
are one-way ratchet teeth, i.e. the teeth are all oblique toward one
direction, inclining
toward the direction of the arrow inside the rack slot as shown in Figure 13.
In this
way, when a force is exerted in a direction opposite to the inclining teeth,
i.e. the
opposite direction of the arrow, due to the barbs between the toothed rack and
the
toothed block, an external force is required to separate them to enable the
toothed
block to slide in the rack slot. While in the inclining direction of the
teeth, i.e. the
direction of the arrow, the toothed rack can drive the toothed block to
overcome the
elastic force and automatically disengage from the teeth of the toothed rack
without
any external force, and thus realizing quick one-way sliding.
Specifically, the meaning of one-way ratchet teeth is that the teeth of the
toothed rack
extend obliquely upward from the edge of the slot, inclining toward the arrow
direction inside the rack slot as in Figure 13. When the opening needs to be
enlarged,
i.e. the first handle is pulled down from the top of the rack slot (i.e.
moving toward
the opposite direction of the arrow), a trigger member is needed to disengage
the
toothed block from the toothed rack, and when the first handle is pulled up
from the
lower part of the rack slot (i.e. moving toward the direction of the arrow),
because of
the one-way ratchet teeth, even if the toothed block and toothed rack are in
engagement, the toothed block can still move along the rack slot freely. Thus,
in the
enlarged status of the jaw opening, put the object into the opening, and then
shrink the
opening just to match the size of the object to grip it.
The adjustable pliers can be water pump pliers, pipe pliers or other pliers,
wherein
both of the gripping parts are hook-like, and teeth are arranged on the edges
of the
inside flank thereof to facilitate gripping and engaging. The gripping parts
can be
integrated with the handles, or can be connected to the handles via connecting
means
as well.
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The position of the first handle 5 and that of the link mechanism is
relatively fixed.
The link mechanism comprises a pivot 11 which is arranged in the through-hole
of the
toothed block 3, and a trigger mechanism which is connected with the pivot.
The
trigger mechanism drives the pivot to rotate, and the pivot further drives the
toothed
block to rotate, thus disengaging the toothed block from the toothed rack and
making
the relative movement become possible.
The first handle 5 is provided with a first through-hole in the region of the
pivot, the
pivot being cylindrical and its cross-section being circular; and the pivot
passes
through the first through-hole and then passes through the rack slot of the
second
handle 9 to relatively fix the first handle 5 and the second handle 9.
More specifically, the first handle is provided with a lateral hole on its
lateral wall in
the region of the connecting mechanism, which allows the corresponding region
of
the second handle to pass through, forming a first part of the first handle
located over
the second handle and a second part of the first handle located under the
second
handle; wherein the pivot passes through the first part of the first handle,
and then
through the rack slot of the second handle, and further through the second
part of the
first handle. The toothed block is located inside the rack slot of the second
handle
engaging with the rack slot.
One flank of the toothed block is provided with teeth which can engage with
the
toothed rack, and the other flank correspondingly is provided with a fixing
part and an
elastic piece, wherein the elastic piece is connected to the fixing part and
propped
against the second handle. Specifically, the fixing part can be a spring hole,
and the
elastic piece is concretely a spring 8, and the spring is arranged inside the
spring hole
propped against the second handle. Accordingly, after releasing the trigger
member,
the teeth of the toothed block can recover to the status of engagement with
the teeth
on the toothed rack due to the effect of the spring, thus the pliers can be
normally
used.
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,
In the second embodiment, as shown in Figures 13-16, the outside of the pivot
11 is
provided with a spiral second groove 12 with a guiding pin 31 on it, and the
other end
of the guiding pin extends into the toothed block through the lateral part.
The trigger
mechanism 4 further comprises a trigger switch 41, after the trigger switch
produces a
downward force, the guiding pin 31 starts to rotate along the spiral second
groove 12,
thereby drives the toothed block 3 to rotate and disengage from the rack slot,
thus the
first handle can move along the rack slot relative to the second handle.
The trigger mechanism further comprises a toothed ring 42 and a spring 43; the
toothed ring 42 is provided with internal teeth and is fixedly arranged inside
the
depression of the outer side of the first part of the first handle; the spring
is arranged
inside the toothed ring beneath the trigger switch and inside the depression
of outer
,
side of the first part of the first handle. The trigger switch is provided
with external
teeth which can engage with the internal teeth of the toothed ring. Normally,
the
trigger switch and the toothed ring are separated; with the effect of the
spring the
trigger switch is jacked up by the spring and the external teeth of the
trigger switch
are separated from the internal teeth of the toothed ring. After the trigger
switch is
pressed, the external teeth of the trigger switch go inside the internal teeth
of the
toothed ring; because the toothed ring is fixed, after the internal teeth of
the toothed
ring engage with the external teeth of the trigger switch, the trigger switch
stops
rotating and the guiding pin 31 starts to rotate along the spiral second
groove 12, thus
driving the toothed block 3 to rotate. The inner diameter of the spring
decreases
gradually from the bottom to the direction of the trigger switch, the bottom
is
arranged inside the toothed ring 42 with internal teeth, which is inside the
depression
of the outer side of the first part of the first handle, and the top is in
contact with the
bottom of the trigger member.
The pivot is provided with a smaller head on the trigger member which is
outside the
first part of the first handle over the second handle, thus the pivot can be
fixed inside
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CA 03053588 2019-08-14
the trigger member outside the first handle. While the other end of the pivot,
i.e. the
outer side of the second part of the first handle, is fixed via a fixing
member 10. The
other end of the pivot can be a thread and the fixing member 10 can be a nut,
and
accordingly, the pivot can be fixed by rotating the thread into the nut.
The invention has been exemplified above with reference to specific
embodiments.
However, it should be understood that a multitude of modifications and
variations can
be made by a common person skilled in the art based on the conception of the
present
invention. Therefore, any technical schemes, acquired by the person skilled in
the art
based on the conception of the present invention through logical analyses,
deductions
or limited experiments, fall within the scope of the invention as specified in
the
claims.
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