[0001] The present invention relates to a pipe bending machine having an improved movement
transmission to a bending die.
[0002] In the existing pipe bending machines the machine comprises a body and a head. Housed
in the body is a motor, whose output shaft supports a driving gear wheel in the machine
head. The driving gear wheel engages a driven gear wheel that is rigidly connected
to a pipe bending die. It is evident that greater is the diameter of the pipes to
be bent, higher is the required motor power, and also the transmission gear wheels
must be suitable to the required torque. Increased required torque needs increased
sizes of the machine, and as a result also the cost of the machine rises.
[0003] U.S. Patents Nos. 3,302,505 and
5,709,144 in the name of Shiokawa both relate to a machine press characterised by being small
in size but producing a high pressure. Among the solutions chosen by that inventor
for achieving his objects, provision is made that the power is transmitted from a
driving gear wheel to a driven gear wheel by interposing a couple of idle pinion gears
between said gear wheels. Whereby, as said in those patents, "the force conveyed by
the rotation is doubled, so that the diameter of the gear wheel can be reduced by
half. As the result, it becomes possible to reduce the measurements of the machine
by placing all the gears in the frame and also to reduce the wear and noise of each
part".
[0004] According to the present invention, what is taught with reference to a machine press
is thought to be transferred to another kind of machine, such as a pipe bender, taking
the same solution with the purpose of obtaining either reduced sizes or, alternatively,
an improved performance of the pipe bending machine.
[0005] In this context, the technical problem at the basis of the present invention is to
provide a pipe bending machine having an improved movement transmission to a bending
die in order to overcome above cited drawbacks relating to the encumbrance and low
transmitted power in the state of art.
[0006] In particular, an object of the present invention is to provide a pipe bending machine
having an improved movement transmission to a bending die, the pipe bending machine
having reduced-size gear wheels maintaining the same power transmitted from the driving
gear wheel to the driven gear wheel.
[0007] The object is generally achieved by a pipe bending machine having an improved movement
transmission to a bending die, the machine comprising a body and a head, a motor being
housed in the machine body and having an output shaft supporting a driving gear wheel,
which is located in the machine head, and a driven gear wheel, which is connected
to a pipe bending die, being located in the same machine head, wherein a couple of
intermediate gear wheels engage both the driving gear wheel and the driven gear wheel.
[0008] As one can see, the Applicant developed a so called translation invention, transposing
a device from a technical field, where said device is already known, to another one
in which the device is not yet employed.
[0009] Further features and advantages of the present invention will be more evident by
a schematic and therefore not limiting description of an embodiment of a pipe bending
machine having an improved movement transmission to a bending die as shown in the
accompanying drawings in which:
figure 1 is a cut axonometric view, with some parts being removed, of a pipe bending
machine according to the invention;
figure 2 is a partially cut top plan view of the pipe bending machine in figure 1,
with the bending die being removed; and
figure 3 is a general axonometric view of the pipe bending machine according to the
invention, with a pipe ready to be bent.
[0010] First referring to the axonometric view in figure 1, therein a machine body is indicated
as 1 and a machine head as 2. Conventionally, situated inside the machine body is
a motor 3, generally an electric motor. A driving gear wheel 5 is keyed to the output
shaft 4 of the motor 3. Located on the machine head 2 is also a bending die 6 (only
partially shown) that allows pipes to be bent in a known way. The bending die 6 is
rotated by a shaft 7 to which a driven gear wheel 8 is keyed. According to the present
invention, as best shown in the top plan view of the pipe bending machine in figure
2 (with the bending die being removed), intermediate gear wheels 9 and 10 are interposed
between the driving gear wheel 5 and the driven gear wheel 8. The intermediate gear
wheels 9 and 10 engage at the same time both the driving gear wheel 5 and the driven
gear wheel 8. In such a way the intermediate gear wheels 9 and 10 both transmit a
movement of rotation from the driving gear wheel 5. If the driving gear wheel rotates
in a direction, also the driven gear wheel 8 rotates in the same direction.
[0011] Thanks to the present invention, the power transmitted from the motor 3 to the bending
die 6 being equal, the size of the gear wheels of the transmission and then of the
machine head 2, and generally of all pipe bending machine, can be reduced.
[0012] With reference to figure 3 shown therein is a general axonometric view of the pipe
bending machine in which the present invention is embodied. A pipe T that is positioned
between the bending die 6 and the counter bending die 11, ready to be bent, is therein
shown.
[0013] Thanks to the present invention, the sizes of the machine being equal to those of
the precedent machines having a reduced performance, to develop improved bending performance,
up to the double of the present one, is made easier.
1. A pipe bending machine having an improved movement transmission to a bending die,
said machine comprising a body (1) and a head (2), a motor (3) being housed in the
machine body (1) and having an output shaft (4) supporting a driving gear wheel (5),
which is located in the machine head (2), and a driven gear wheel (8), which is connected
to a pipe bending die (6), being located in the same machine head (2), characterised in that a couple of intermediate gear wheels (9, 10) engage both the driving gear wheel (5)
and the driven gear wheel (8).
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only.
It does not form part of the European patent document. Even though great care has
been taken in compiling the references, errors or omissions cannot be excluded and
the EPO disclaims all liability in this regard.
Patent documents cited in the description