Note: Descriptions are shown in the official language in which they were submitted.
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A METHOD AND DEVICE FOR CONNECTING AT
LEAST TWO RODS
.
The present invention relates to a method for connecting
at least two rods, wherein an apparatus, which is provided
with a rotatable grabbing means, seizes a wire loop, which
extends around the rods, and twists the loop during a
pulling movement, and to a device for accomplishing the
method. Such a method and device are generally used for
securing reinforcement steel rods during the production
of reinforced concrete structures, the reinforcement
steel rods usually lying one above the other in an orthogonal
manner and being interconnected at their points of
intersection.
A plurality of methods and devices are known for
accomplishing the securement of these reinforcement rods,
such work often being undertaken by specialists under contract.
Since it is necessary to secure a very large number of
intersection points, especially in the case of large-
scale buildings, a number of apparatus which operate
automatically or semi-automatically have been designed
and patented, but noneof these apparatus have yet been
successful on the market, since they are usually too complex
or become faulty with rough handling on a building site.
For this reason, simple methods and apparatus still exist,
which depend mainly on the skill and stamina of the
specialist worker. In such a case, prefabricated wire
loops are used which have rings or eyelets at their two ends.
As a result of the required flexibility and, hence,
minimum thickness of the wire, for safety reasons, two of
these wire loops are manually placed around the particular
rods to be connected, and the four wires of the loops
at the top are seized by a twisting apparatus which comprises
a rod with a hook, the rod being knurled and extending in
a suitable handle so that, when the handle is pulled, the
rod and, hence, the hook are set in rotation. This method
2 2344~-266
and apparatus have the advantage of being simple, but the appara-
tus, which is only formed from two component parts, has the con-
siderable disadvantage that the wire loops have to be inserted
beneath the rods to be connected, so that the person carrying out
the work has to bend down law if, as is generally the case, the
reinforcement rods are on the ground. In addition, the wire loops
have to be carried in one hand whilst the apparatus is operated
with the other hand. In order to permit as many wire loops as
possible to be seized at any one time, the connection points
should not occur at the eyelets and, as a consequence thereof, it
is necessary to weld-on the eyelets instead of twisting them.
This means that two wire loops with four welding points are re-
quired per working operation, and consequently the production of
these wire loops becomes labour-intensive and, as a result,
relatively costly.
By comparison, the present invention seeks to provide a
method and a device for accomplishing the method, whereby it is
easier and quicker for the operator to connect at least two rods,
and whereby the material costs for a connection can be reduced.
This object is achieved by the method and device described in the
claims.
Therefore, this invention seeks to provide a method for
binding at least two rods, comprising the steps of: providing a
binding apparatus having a rotatable grabbing means; providing a
wire clamp having a pair of leg portion ends provided with comple-
mentary locking means; positioning said wire clamp around the rods
from a first side thereof whereby said leg portion ends extend to
a second opposite side of said rods; engaging said complementary
2a 23444-266
locking means on said second side; grasping said wire clamp from
said first side with said grabbing means; rotating said grabbing
means to thereby twist said wire clamp and bind said rods.
The invention further seeks to provide a device for
binding a pair of rods, comprising: a housing; a displaceable
dispensing means attached to said housing for the forward con-
veyance of a wire clamp having a pair of leg members provided with
complementary locking means, said dispensing means being disposed
on a first side of said rods; closing jaws pivotly attached to
said housing; said closing jaws being adapted to bring the comple-
mentary locking means on the wire clamp leg members into engage-
ment on a second, opposite side of the rods, and grabbing means
disposed on said first side of the rods for subsequently twisting
the wire clamp to thereby bind said rods together.
The invention is explained more fully hereinafter with
reference to embodiments.
Figure 1 is a top view of a partially cutaway portion of
a first embodiment of the device according to the invention;
Figure 2 is a longitudinal sectional view of the device
of Figure 1;
Figure 3 shows an enlarged detail of Figure 1;
C
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Fig. 4 is a longitudinal sectional vie~ of the
enlarged aetail of Fig. 3;
Fig. 5 is a sectional view, on an enlarsea scale,
taken along the line V - V of Fig. l;
Fig. 6 is a sectional view taken along the line
VI - VI of Fig. 3;
Fig. 7 shows a phase during the connecting operation;
Fig. 8 is a top vie~ of an enlarged detail of a secohd
embodiment of the invention;
Figs. 9 to 12 show a wire clamp of the invention
from different sides and in two different working positions;
Figs. 13a and 13b are plan views of a third, preferred,
embodiment without a cover
Figs. 14a and 14b are longitudinal sectional vie~s
of Figs. 13a and 13b;
- Figs. 15 to 17 show three different phases of the
closing procedure of the third embodiment;
Fig. 18 is a longitudinal sectional view of Fig. 16;
Fig. 19 is a sectional view taken along the line
XIX - XIX oF Fig. 13a;
Fig. 20 is a sectional view taken along the line
XX - XX of Fig. 13a;
Fig. 21 is a sectional view taken along the line
XXI - XXI of Fig. 16;
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Fig 22 is a plan view of wire clamps accoroing to an
additional embodiment which are attached to a strip;
Figs. 23 and 2~ are sectional views of a wire clamp
of FiS. 22, viewed from both sides; and
Fiss. 25 tn 27 show three production examples of a
wire clamp of Fig. 22.
Instead of using two separate wire loops which each
have two eyelets, the method of the invention utilises
a wire clamp or clip 1 (shown in Figs. 9 to 12) which
is closed upon itself and it V-shaped when viewed from the
side (see Fig. 9). At their lower ends, the two leg
portions 2 and 3 are provided with locking means which,
in the present example, comprises a hook member 4 on the
leg portion 2 and a loop 5 on the other leg portion 3.
As can be seen from Fig. 10 in particular, the hook member
4 is formed from the two welded end sections of the leg
ZO portions and is bent out of the plane of the leg portions.
As can be seen from Figs. 9 to 12 and from the descrip~ion
of these Figures, the single wire 6 is also doubled -over
here to permit, on the one hand, a suitable flexibility
and, on the other hand, an adequate tensile strength to be
achieved. However, in the case of the hook member 4, the
wire is only welded at one point, thereby simplifying the
production of a clamp for a connection point. The transitional
point 7 between the two leg portions is rounded a$ the
apex and has a shoulder ~ on each side, the significance
of this shoulder 6 being explained hereinafter in connection
with the binding apparatus. The wire clamp may be produced
from any suitable material, such as has been used in the
past, but the usual reguirements regarding deformability,
weldability and tensile strength have to be met.
34
In contrast to all other known me~hods, the wire clamp,
as shown in Fis. 9 is now brought from above over the
steel roas, which are to be connected (see zlso Fig. 1).
Subsequently, the lower enos of the two leg portions are
interconnected by the locking means 4 and 5, ~hereupon the
hook member of the binding apparatus seizes the transitional
point 7 of the wire clamp and twists the upper portion
of the clamp. Because the connection is effected from
above, and because the wire clamp no longer needs to be
manually inserted underneath the steel rods, the work
is considerably facilitated, since the operator no longer
needs to bend down to such a low level. Two embodiments
of a device are described hereinafter, which device permits
the locking means of the wire clamp to become engaged
without the need for the operator to take the wire clamps
into his hand, with the result that the connection is
effected by a single moving operation of the device.
Consequently, the most important object of the device
is to bring the locking means of the clamp into engagement
ZO beneath the rods to be connected and subsequently to
seize and twist the transitional portion at the top
of the wire clamp, all this being achieved in one working
operation.
The device for accomplishing the method mainly
includes a binding apparatus 9 and the wire clamps 1 which
may possibly be disposed on a support means. The binding
apparatus 9 is provided with a rectangular, hollow housing
10 which, in a preferred embodiment, serves also as
a magazine for the wire clamps 1. The front end of the
housing 10 extends into a locking portion 11 pro~ided
with closing jaws 12. The ends of the leg portions of
the wire clamps 1 are provided with locking means and
are bent by the closing jaws 12 in such a manner that the
locking means engage with one another. The displaceable
gripping member 13 is disposed around the housing so
as to be slidable thereon and serves to seize the
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foremost wire clamp from the magazine and move it
forwardly, i.e. ~ownwardly. A suide bush 14 is mounted
on the front portion of the housing,and a knurled
rod 15, which is provided with a binding hook 16 is
disposed in the guide bush 14 in such a manner that the
knurled roa 15 is set in rotation when a relative movement
occurs between the guide bush 14 and the knurled rod 15.
A slide member 17 is also provided in the front portion
of the guide housing and is advanced by the pressure
of a spring 15 in order to push the wire clamps 1
fnrwardly and to bring the foremost clamp of the wire
clamps into a position from which this clamp can be
advanced by the gripping member 13. A compression
spring 19 is provided on the knurled rod 15 and pushes
the guide bush 14 back into its initial position after
the binding process has been completed.
As can be seen from Fis. 5 in particular, the housing
10 is formed from two telescoped, U-shaped housing
portions which accommodate the wire clamps 1. The wire
clamps are held-do~n in the centre by a bar 20 so that the
clamps cannot slide over one another. As can be seen from
Fig. 1 or 3, the lower plate Zl of the housing is bent in
a U-shaped manner and is split from the front to the
binding hook 16, the plate Zl extending into a projection
member 2Z (see Fig. 4 in particular) which has an inclined
front end 23 abutting against the foremost wire clamp.
According to Fig. 5, a slide bar 24 is attached to the
underside of the gripping member 13, on each side of the
held-down bar 20, and it slides into a slot 25 in the
U-shaped upper portion 26 of the housing 10. The end
of the slot 25 also serves as a stop means for preventing
the possibility of the displaceable gripping member 13
being pulled further back. As can be seen from Figs.
3 ano 12, the slide bars 24 engage in the shoulders 5
of the wire clamp in arder to advance the clamp. The
result of this is that the cooperation between the hold-
down bar 20 and the slide bars 24 and the projection member
22 permits only one wire clamp at a time to be seized in
succession and prevents indivioual wire clamps from sliding
over one another.
In the closing section of the housing, the lower
housing portion 21 and the upper housing portion 26 each form
a respective passage 27 on both sides, wedge-shaped guide members
2~ being disposed in the passage 27 and having a triangular
configuration, when viewed from above. As can be seen from
the various positions of the leg portions of the wire clamp
in Fig. 3, when the wire clamps are inserted through the
displaceable gripping member, the wedge-shqped guide
members cause the leg portions to be drawn together until
they are brought fully into their closed position by the
closing jaws.
In the first embodiment, the wire clamps is deformed by
displaceable closing jaws in order to bring its locking means
into engagement. In Fig. 1, the apparatus is shown in its
open position and, in Fiy. 3, the apparatus is shown in its
closed position. A first, displaceable closing jaw 29 is shown
which is rotatable about a rotatable axle 31a, and a second,
displaceable closing jaw 30 is shown which is rotatable
about a rotatable axle 31b. The two closing jaws are
actuated by a U-shaped closing spring 32, and the ends of the
spring act on the closing jaws. As indicated in Figs. 1, 3
and 5, two rollers 34 are provided on the displaceable
gripping member 13 and act on the closing spring. As also
follows from these Figures, during the forward movement of
the displaceable gripping member, the rollers 34 cause the
spring 32 to be compressed, and the two closing jaws also
become compressed by this movement. As can be seen from
Fig. 3, the ends of the wire clamps during the closing
movement initially sliae along the inclined face 35
of the weage-shaped guide members 2~ ana subsequently
pass behind the cams 37. From there, the enas pass
over the bearing surface 38 on the upper closins jaw
(shown in the drawing) and onto the bearing surface 35
on the lower closing jaw.
The t~o closing jaws have different forms since the
two ends of the wire clamp do not effect the same movement.
Thus, the end of the wire clamp provided with the loop 5
is bent more intensely than the other end, which
is provided with the locking hook 4. In the upper closing
jaw 25 there is a recess 4D which accommodates the loop
end of the wire clamp. The end 41 of the other closing
jaw 30 is milled in order to accommodate the end of the
wire clamp which is provided with the locking hook 4, as
can be seen in Fig. 3. Fig. 7 shows the wire clamp in
its end position, and it can be seen that the loop is
placed over the locking hook in such a manner that the loop
engages behind the hook during a withdrawal movement. It
can also be seen from Fig. 7 that, in the end position, each end
of the wire clamp slides out of the passage formed by the
lower U-shaped plate 21 and cams 37 since,in this
position, the wire clamp has the thinnest point when viewed
from the side.
The following workiny operation results from the
description and from Figs. 1 to 7: During the advancement of
the binding apparatus over a point of intersection bet~een
two rods A and 0 which are to be connected, the binding apparatus
abuts either with the closing jaws against the base C or
with the locking hook against the upper rod A. With f~rther
advancing movement, the displaceable gripping member 13 is
pushed forwardly. Consequently, as shown in Fig. 3, the
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wire cla~p is forced into the closing jaws. At the
same time, the closing jaws are c10s2d, so that the
locking loop S is placed over the locking hook 4. During
a pull-back movement, the locking loop is initially locked
with the locking hook on the wire clamp, and the entire
binding apparatus is pulled-back. Since the binding
hook is in engagement with the wire clamp and the locked
clamp abuts against the rod B durins the pull-back
movement, the binding hook is set in rotation by the
upward movement of the guioe bush, and the upper end of
the wire clamp becomes twisted at the transitional
point. Now it is only necessary for the binding hook to
be pulled out of the eyelet formed after the twisting
movement, and the connection is thus achieved.
According to a second embodiment shown in Fig. 8,
the closing means and the guide jaws can be considerably
simplified. ~ith the exception of the locking member,
the apparatus with its displaceable gripping member
is identical to the one described above. Contrary to
the first embodiment, the locking member 42 does not
contain any displaceable closing jaws, but only contains
two rigid closing jaws 43 which may be operated in an identical
manner. The rigid closing jaws 43 have an arcuate closing
edge 44 by which the two ends of the wire clamp are
guided towards each other in order to come into the
closed position shown in Fig. 7. In addition, each end
of the wire clamp is directed onto this closing edge at
a suitable angle by means of a cam 45 which is disposed
opposite the closing edge, this cam having a guide face
which is rDughly semicircular. The function of this
locking member is the same as in the first embodiment, but
this locking member has the advantage of having no
displaceable component part.
The closing jaws 43 are subject to considerable wear
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and, in order to permit them to be replaced easily, they
are secured to the lower housing portion 21 by means
of screws 46.
It follows from the description that this new apparatus
permits two rods to be interconnected in a forward and
backward movement without the need for bending-down for
reinforcement rods on the ground. Since the entire working
operation only consists of pushing and pulling movements,
it i8 also possible for less skilled persons to be used
for this work. Within the scope of the present invention,
it is possible for various details to be changed. Thus,
for example, it is possible to provide the magazine component
in such a manner that wire clamps attached to a suitable
carrier such as cardboard or plastic, can be inserted
into the apparatus. In addition, it is possible for the
magazine containing the wire clamps to be disposed laterally
on the hou~ing of the binding apparatus, i.e. at right
angles to the closing movement, whereby the apparatus
Z0 has a suitable aperture and the side member, which advances
the individual wire clamps, is adapted accordingly.
It is also possible to alter the locking means on the
wire clamp, i.e. to dispose the loc ~ g hook and the locking
loop in a different plane. With reference to Fig. 9, this
means that the locking hook 4 projects, either upwardly or
downwardly, from the plane formed by the leg portions which are
disposed in a V-shaped manner, and that the loop-like end of
the leg portion 3 is bent accordingly. Instead of being
formed from a wire, the clamps may also be formed from
p~eces of sheet ~etal strips.
For further, simplified work, it is possible to effect
twisting by a battery-powered drive means instead of by pulling
the apparatus, and such drive means permits work to be carried
out more rapidly in an energy-saving manner.
figs. 13a to 27 illustrate an additional, preferred
arrangement, which is similar to the device of the second
embodiment, with fixed jaws and provides a further improvement
in respect of the wire clamps being securely hooked in
position, their being separated and positively inserted into
the closing device. As will be described in more detail
hereinafter, this improvement is achieved because a displaceable
member in the closing region causes, on the one hand, the wire
clamp to be brought into a secure closed position and provides,
on the other hand, a positive separation of the wire clamps in
order to bring them positively into the correct initial position.
As can be seen from Figs. 14a, 14b and 18 in particular,
the knurled rod 15 with the binding hook 16 extends parallel to
the housing 50 of the binding apparatus 51 and, hence, parallel
to the gripping member 52 also, thereby pemitting a particularly
compact and space-saving arrangement to be achieved. At its
front end, the housing 50 extends into a locking member 53
which includes two r~gid closing jaws 54 and 55. The rear
of the knurled rod 15 is rotatably mounted and secured in a
resilient bearing 56. The bearing 56 is connected, by
means of resilient connections 107, to two springs 108 in
spring housings which are connected to the gripping member.
Fig. 14a also shows the cover 57 which is pivotally mounted
at its rearD i.e. on the left of the drawing, on a bearing
58. A guide bush 59 comprises two rollers and is disposed
in the front region of the housing (see Fig. 18). The knurled
rod with the binding hook can be set in rotation by means of
the guide bush 59. Fig.13a shows a clamp slide 60 which is
actuated by the spring strips 69 and pushes the wire clamp~
61 in a forwardly direction, the springs running along the spring
rollers 70.
The rear end of the gripping member 52 with the handle
62 is connected to the housing base 65 by means of an
expansion bolt 63 which slides in a slot 64 in the housing
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base 65. The gripping member 52 is additionally provided
with a rod guide 106 which may be used to keep the apparatus
upriyht with the aid of an extension rod, if connections
are to be formed on the base. The front end of the gripping
member is connected by two screw bolts 66 to a T-shaped
member 67, which slides in the lower housing portion and
has a multiple function; the screw bolts sliding in a
longitudinal slot 7Z in the housing base 65. A slide member
~5 is connected to the T-shaped member via a spring 89 and
is slidably disposed above the longitudinal leg portion 57
of the T-shaped member; the front portion of the slide
member ~B being provided with two projection members 76, which
engage in two shoulder~ 77 in each particular foremost wire
clamp 61a.
The closing movement is now described with reference to
Figs. 15, 16 and 17, and the multiple functions of the T-
shaped member and of the component parts which are displaced
by this T-shaped member are also explained. In Fig. 15
the apparatus is shown in its initial position, the foremost
wire clamp 61a having been brought into this initial position
by means of a loading movement. The foremost wire clamp
61a is pressureless in the apparatus, and the pressure which
is exerted by the clamp slide 60 is absorbed by the wire clamp
Z5 61b situated therebehind, the two ends of the wire clamp
61b abutting against a shoulder 73 of a pawl 74 provided
with pivot 75. During the forward movement of the handle
SZ, the T-shaped member 67 which is connected thereto is
also moved forwardly until it is in the position shown in
Fig. 16. In this position, the projection members 76 on
the slide member 5~ engage with the shouders 77 of the fore-
most wire clamp 61a and the front of the slide member abuts
against the stop members 71 of the two closing jaws. The
locking members of the wire clamp thereby pass into the
respective guide passages 75 and 79 (see Fig. 16); they
are bent in accordance with the respective guide passage and
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brought into their closed position. Whereas the guide
passage 7B - the upper passage in the drawing - is a milled
portion in the upper closing jaw 5~, the other guide passage
79 is situated ~n a rotatable member ~0 which is mounted so
as to be rotatable about a journal 81.
During the subsequent forward movement, during the trans-
fer to the position shown in Fig. 17, only the T-shaped
member 67 is still moved forwardly in opposition to the
10 pressure of the spring ~9, the short leg portions 68 of the
T-shaped member 67 actuating two cam slides 05 and ~5a which
are disposed in the closing jaws and are each actuated by a
spring 105. Each of the two cam slides is provided with
a pawl pin 62 for actuating the pawls 74, whereas one of the
15 two cam slides - ~5a - additionally has a shoulder ~4 which
acts on a pin ~6 on the rotatable member B0 in order to
rotate the rotatable member 00. Fixed cam members having a
recessed portion 103 are subsequently moulded on the cam
slides, and the third wire clamp 61c (see Fig. 17) engages
20 in said cam members at the very moment when the second clamp
61b oecomes free. Rotation of the rotatable member
induces that portion of the wire clamp which is situated in
the guide passage 79 to be rotated outwardly in order to
bring the locking means of the wire clamp into secure engagement.
Upon withdrawal of the gripping member, the pawls 7~
are brought into their initial position and the wire clamp
61c abuts against the shoulder 73 of the pawl, whereas the
wire clamp 61b - which is nDw foremost - is pressureless and
30 can be pushed into the guide passages. For this purpose,
however, the wire clamp 61;~ must previously be raised from
the appropriately shaped projection members 76 on the slide
member. So that the foremost wire clamp securely abuts
against the projection members after this operation, this
35 wire clamp is pressed downwardly by means of a spring 109
(see Fig. 1~).
