FIELD OF THE INVENTION
This invention relates to bar bending tool, such as metallic bar and especially for steel bar
using in reinforcement of cement concrete. This tool is broadly using in building construction
and grill making, so have a important role to maintain quality of construction work.
Traditional tool have many demerits. The present invention removes all these demerits from
traditional tool.
BACK GROUND OF THE INVENTION
In field of building construction, steel bar in several diameter is to be bend in daily use;
especially reinforcement bar for R.C.C. (reinforcementcement concrete). Most common using
diameter of these bar varies between 6mm to 16 mm and sometime upto 25mm. For
bendingof bar ’Bar bending key’ named tool are in use. These keysare available to bend
8mm, 10mm, 12mm, 16mm, 20mm and above diameter bars separately in each dia. This tool
is available in market in traditional name of ‘Bar bending tool’ or ‘Bar bender’ or‘Bar
bending key’.
Demerits of traditional bar bending keys
These are main back draw of traditional bar bending keys-
1. During bending of bar, key slips generally and accident occur.
2. For each diameterof bar, separate key requires bending it. Due to this facttool operator
and mason tend to avoid carrying all diameter key, which arerequired for good work.
Resolutely shape, size and quality goes-down of bended bar.
3. More key required more material to build tool.
4. More key is costly in purchase.
5. Convey of all key is painful and non portable.
6. Repair is not easily possible of these key.
OBJECT OF THE INVENTION
The object of present invention is to remove demerits of availabletraditional bar bending key
or tool as describe just above. The bar bendingkey presenting through this invention, can
bend all common diameter bar singly. This is slip free, so accident will notoccur. It is very
portable, easy using and have low cast.
Thus the major objects of the present invention are as below-
1. To bend all commonusing diameter bar by this invent single key.
2. To avoid accident occurred by slipping of key during applying force to bend bars.
3. To decrease cost of key set.
4. To get rid of by non-portabilityof traditionalkey/tool.
5. To increase easy and cheap repair and maintains of key.
6. To save steel in manufacture of several keys.
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SUMMARY OF THE INVENTIONThe
present invent ‘Adjustable mouth opening bar bending key’singly can bend up to 16mm
diameter steel bar easily itself instead of so many separate keys required to bend each
diameter bar traditionally.
This Invention can be claimed in following manner-
1. A system and structure of ‘adjustable mouth opening bar bending key’ contains
rectangle shaped arm (1), Round shaped handle (16) at one end, and fix jaw (19) is
made on other end, of this arm (1), Handle (16) had grooved (21) on its surface and a
‘rectangle shaped slot duct’ (17) in it.
2. The system and structure as claimed in claim- 1 wherein said arm (1) have a fixed Jaw
(19) and this jaw contains threads inside (18) and a bracing shape (20) and a rectangle
slot (6).
3. The system and structure as claimed in claim 1-2 Wherein said arm (1) have
rectangle slot (9) and a round hole (15) and a inside threaded hole (22) to hold screw
(14),with steel wire (13)and two number stiffener bar (2) situate on both side of
arm(1).
4. The systemand structure as claimed in 1-3 wherein said steel wire (13) is fixed with
screw (14) to arm (1) at one end and welded clipper (12) at other hand. The screw (14)
gripes with threaded hole (22) with arm (1).
5. The system and structure as claimed in 1-4 wherein said clipper (12) is weld with
magnetic lock nail (11).
6. The system and structure as claimed in 1-5 wherein said screwed jaw (3) have a rod
(4) and threads (5) on rod and a rectangle slot (7) and a rectangle slot (10).
7. The system and structure as claimed in 1-6 wherein a bar lock magnetic strip (8) exist.
This is to be placed in rectangular slot (6) and (7).
Brief Description of the drawing
Figure 1-illustrate a bird eye view of invent bar bending key.
Figure 2 -illustrate the longitudinal section of key.
Figure 3-illustrate the bird eye view of moveable screwed jaw.
Figure 4-illustrate the longitudinal section of moveable screwed jaw.
Figure 5-illustrate the detail of magnetic lock nail.
Figure 6-illustrate the detail of bar lock magnetic strip.
Detail description of the invention
As per figure no.1 ‘At a glance’ shape of ‘adjustable mouth opening bar bending key’ is like a
stick/rod shaped arm; consisting several component in it. In this component, at left side end it
consists Handle (16), and right side end, it consists a arm (1). The Handle (16) is made of solid round
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section, but a slot (17) is existing at its free end. For better grip there is light grooves (21) are given at
its surface. Other end of handle (16) is joints to working arm (1).
A fixed jaw (19) is situating on free end of arm (1). For stiff and ridge joint between arm (1) and
fixed jaw (19), the bracing (20) is given. The fix jaw consist a rectangle slot (6) to hold bar lock
‘magnetic strip’ (8), during bending of bar in certain cases (as bending bar, having diameter more than
12 mm and when applying of force for bending, is not in proper alignment). The Fix Jaw (19) has a
hole (23) inside its body and this hole is inner threaded (18), to hold movable Jaw (3).
The arm (1) has four more important components as described in above paragraphs. First, a
slot (9) throughout its depth, for the purpose of, to stop lateral movement of movable jaw (3) during
bending of bar. Second,round duct with ‘inside thread’ (22) to hold screw (14) on arm (1). This screw
have a purpose to carry, steel wire (13) with arm (1). As per figure no.1 one end of steel wire (13) is
fixed with arm (1) by screw (14) and its second end holds clip (12) which holds magnetic nail (11).
Clip (12) helps to pick-up and insert of the magnetic nail (11) in to slot no. (9) easily. Third,a round
hole (15) to give a safe place to hold/rest the magnetic nail (11) when it is not insert in slot number
(9). The ultimate object of these three components is to carries magnetic nail (11) forever with arm
(1). Fourth, two number stiffening element (2) casted with arm (1). These element fill up the strength
of arm (3), decreased due to cavity created by slot no.(9) and hole (15) formagnetic nail (11) and
screw’s hole (22) and hole no.(23) for moveable jaw (3) holding.
Other important component of this tool is, a movable Jaw (3). It consist a rod (4) which is thread (5)
outside, and a slot (7). The threaded rod [(4) and (5)] holds movable jaw to arm (1) with property of
‘to set variable distance’ between both jaws [(19) and (3)]. This movable Jaw (3) also has a rectangle
slot at its free end. The purpose of this slot is to hold the ‘bar lock magnetic strip (8). The threaded rod
(5) has a slot (10) also on it through full depth as per figure no. 3 and 4. When the gap between both
jaws [(19) and (3)] decided finally as per requirement; the magnetic nail (11) does place in to slot no.
(9). This nail (11) also pass through slot no. (10) of movable jaw’s rod(4). By doing this lateral
movement of movable jaw (3) does not occur. Movable jaw (3), threaded rod [(4) and (5)] and ‘bar
lock magnetic strip (8) are monolithic among. This set can remove or pull out from arm (1) and fixed
jaw (19) by spinning the movable jaw (3) in required direction.
A independent component of this invent tool is ‘bar lock magnetic strip (8). This component checks to
slip the key apart from ‘bar surface’ to be bend; during applying the force on handle (16). This strip
(8) demand to be place in slot [(6) and (7)] just after griping bar (to be bend) between both jaws [(19)
and (3)] and before applying force on handle (16). The inner size of slot no.6 and slot no.7 is equal
and just more to outer size of ‘bar lock magnetic strip (8). When tool is not in use the ‘bar lock
magnetic strip (8) will be placed in slot no. (17) Which is situated at the free end of handle (16). The
magnetic property of this ‘bar lock magnetic strip (8) helps to hold it in slot no. (17) or slot no.(6 and
7) as per situation.
Process and method to use this tool.
The process and method of ‘to bend any bar’ with this invent tool/key is very simple. This is
describing in some steps as below.
Step-1
Remove the magnetic nail from slot(9).
Step-2
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Set the distance between both jaw [(19) and (3)] some millimetres more, than the diameter of ‘bar to
be bend’; by rotate the movable jaw (3) in required direction.
Step-3
Placed magnetic nail (11) in to slot no.(9).
Step-4
Move the tool near to that place of bar (to be bend) from where it had to bend. Place the jaws [(19)
and (3)] in such manner on bar, that the place to be bend become between these jaws.
Step-5
Pick the ‘bar lock magnetic strip (8)’ from slot no. (17) and place in to slot no. (6) and (7), to avoid
slipping of key from bar surface, if needed.
Step-6
Apply the force on handle to bend the bar till goal achieves.
Step-7
Remove the ‘bar lock magnetic strip (8)’ from slot no. (6) and (7), and place it into slot no. (17).To
bend new place of bar follow step-1 to step-7 in every case.
Advantage of this invention
1. To bend all commonusing diameter bar by this invent single key.
2. To avoid accident occurred by slipping of traditional key during applying force to
bend bars.
3. To decrease cost of key set.
4. To increase portability of key set.
5. To increase easy and cheap repair and maintains of traditional key set.
6. To save steel in manufacture of several key.
7. Grip accuracy is very high of this key.So it can bend any bar closely and accurately.
8. It can also use as adjustable spanner for several diameter nut-bolt in emergency.

I claim:
1. A system and structure of ‘adjustable mouth opening bar bending key’ contains
rectangle shaped arm (1), Round shaped handle (16) at one end, and fix jaw (19) is
made on other end, of this arm (1), Handle (16) had grooved (21) on its surface and a
‘rectangle shaped slot duct’ (17) in it.
2. The system and structure as claimed in claim- 1 wherein said arm (1) have a fixed Jaw
(19) and this jaw contains threads inside (18) and a bracing shape (20) and a rectangle
slot (6).
3. The system and structure as claimed in claim 1-2 Wherein said arm (1) have
rectangle slot (9) and a round hole (15) and a inside threaded hole (22) to hold screw
(14),with steel wire (13)and two number stiffener bar (2) situate on both side of
arm(1).
4. The systemand structure as claimed in 1-3 wherein said steel wire (13) is fixed with
screw (14) to arm (1) at one end and welded clipper (12) at other hand. The screw (14)
gripes with threaded hole (22) with arm (1).
5. The system and structure as claimed in 1-4 wherein said clipper (12) is weld with
magnetic lock nail (11).
6. The system and structure as claimed in 1-5 wherein said screwed jaw (3) have a rod
(4) and threads (5) on rod and a rectangle slot (7) and a rectangle slot (10).
7. The system and structure as claimed in 1-6 wherein a bar lock magnetic strip (8) exist.
This is to be placed in rectangular slot (6) and (7).