Field of the Invention
[0001] The present invention relates to a traversing drum used in an automatic winder or
the like to traverse a yarn while rotating a package.
Background of the Invention
[0002] In a yarn winding device such as an automatic winder, when a yarn is wound around
a package, a traversing drum that is in pressure contact with the package is externally
rotatively driven to wind the yarn while rotating the package. An endless track like
guide groove is formed in a surface of the traversing drum as traversing means for
winding the yarn around the package uniformly in an axial direction of the package.
A traversing operation is performed by guiding the yarn through this guide groove.
[0003] Such a traversing drum is typically formed integrally of metal such as aluminum or
iron. Specifically, a traversing drum is formed by producing a cylinder using a casting
process such as a die cast process or a lost wax process, forming the guide groove
in the cylinder, and subjecting the cylinder to surface treatment based on machining
such as grooving or finishing in order to improve dimensional accuracy.
[0004] The traversing drum is rotated by being externally rotatively driven. The reduced
mass of the traversing drum serves to reduce loads on a rotative driving source (motor).
This makes it possible to reduce power consumption and extend the lifetime of the
motor. However, conventional traversing drums formed of the metal such as iron using
the die cast or lost wax process have the disadvantages of having a very large mass,
consuming high power, and failing to extend the lifetime of the motor. In view of
these problems, it is an object of the present invention to solve these problems to
provide a traversing drum made of ceramics and thus having a small mass.
Summary of the Invention
[0005] Means in Claim 1 employed by the present invention in order to accomplish the object
is a traversing drum which drives a winding package while being in surface contact
with the winding package and which has an endless track like guide groove formed in
an outer peripheral surface of the traversing drum to traverse a yarn in a lateral
direction, the traversing drum being characterized in that a drum main body including
the groove is integrally molded using a ceramic burned member. When the drum main
body of the traversing drum is integrally molded using a ceramic burned body, a traversing
drum can be manufactured which is lighter than conventional ones made of metal. It
is thus possible to significantly reduce the power consumption of a rotative driving
source for the traversing drum and to extend the lifetime of the rotative driving
source.
[0006] Means in Claim 2 employed by the present invention is a traversing drum characterized
in that a drum main body is composed of a double cylinder including an inner cylinder
and an outer cylinder which are integrally molded using a ceramic burned member. When
a traversing drum is manufactured using a double cylinder including an inner cylinder
and an outer cylinder which are integrally molded using a ceramic burned member, it
is rigid and light even if it is thin. It is thus possible to significantly reduce
the power consumption of the rotative driving source for the traversing drum and to
extend the lifetime of the rotative driving source.
[0007] Means in Claim 3 employed by the present invention is a traversing drum characterized
in that a drum main body is composed of a double cylinder including an inner cylinder
and an outer cylinder which are integrally molded using a ceramic burned member and
which are intermittently connected together using ribs. In this aspect of the invention,
the inner cylinder and the outer cylinder are intermittently connected together using
ribs. Accordingly, the rigidity of the traversing drum can be further improved compared
to the aspect of the invention in Claim 1.
[0008] Means in Claim 4 employed by the present invention is a traversing drum characterized
in that a drum main body is composed of a double cylinder including an inner cylinder
and an outer cylinder which are integrally molded using a ceramic burned member, and
ribs are used to connected the inner cylinder to a groove bottom of a guide groove
formed in a surface of the outer cylinder. The operations and effects of this traversing
drum are the same as those of the aspect of the invention in Claim 3.
[0009] Means in Claim 5 employed by the present invention is a traversing drum characterized
in that a drum main body is composed of a double cylinder including an inner cylinder
and an outer cylinder which are integrally molded using a ceramic burned member, and
the inner cylinder is installed over a rotating shaft via bearings each having rubber
rings installed on its outer peripheral surface. In this aspect of the invention,
the bearing having the rubber ring installed on its outer peripheral surface is disposed
between the traversing drum and the rotating shaft. It is thus possible to absorb
a difference in thermal expansion based on a difference in material between the rotating
shaft (metal) of the rotative driving source and the traversing drum, made of ceramics.
This prevents, for example, a failure to transmit a rotative driving force owing to
a possible gap between the rotating shaft and the traversing drum.
Brief Description of the Drawings
[0010]
Figure 1 is a view of a part of an automatic winder comprising a traversing drum according
to a first embodiment of the present invention, showing the traversing drum installed
over a rotating, in a vertical sectional view.
Figure 2 is a vertical sectional view of a traversing drum according to a second embodiment.
Figure 3 is a vertical sectional view of a traversing drum according to a third embodiment.
Figure 4 is a vertical sectional view showing a mounting structure between an inner
cylinder and bearings according to the present invention.
Detailed Description of the Preferred Embodiments
[0011] A configuration of the present invention will be described below on the embodiments
shown in the drawings. Figure 1 shows an automatic winder comprising a traversing
drum 1 according to a first embodiment of the present invention. In this figure, the
traversing drum 1 installed over a rotating shaft 2 is shown in a vertical sectional
view. As shown in this figure, a drum motor 4 is fixed to a frame 3 of the automatic
winder as a rotative driving source. The rotating shaft 2 of the motor 4 has a different-diameter
step portion. Two bearings 5A, 5B are externally fitted over the different-diameter
step portion. The spacing between the bearings 5A, 5B is held by a spacer 6. The two
bearings 5A, 5B are fixed by screwing a drum nut 7 over the rotating shaft 2.
[0012] A surface of a winding package P is contacted with the traversing drum 1 to drive
the winding package P. An endless track like guide groove 8 is formed in an outer
peripheral surface of the traversing drum 1 to traverse a yarn Y in a lateral direction
(the direction along a rotational center line C of the traversing drum 1). A drum
main body including the groove 8 is integrally molded of a ceramic burned member.
The drum main body is composed of an outer cylinder 9 having the guide groove 8 formed
in its outer peripheral surface and inner cylinders 10A, 10B as a bearing supporting
portion. The outer cylinder 9 and the inner cylinders 10A, 10B are integrally molded
of the ceramic burned member. The traversing drum 1 may be manufactured using a lost
wax process or the like. If the lost wax process is used, the traversing drum 1 is
manufactured as a product by pouring wax into a die to form a mold material, pouring
a ceramic material on the mold material, drying and solidifying the ceramic material,
then heating the ceramic material to melt and remove the wax to form a molding base
for the traversing drum 1 of a complicated shape, subsequently baking the molding
base at a high temperature, and finishing the molding base by subjecting it to surface
treatment or the like. In this respect, after the wax has been melted and removed,
the remaining wax may be further completely burned before the molding base is baked
at a high temperature.
[0013] The traversing drum 1 is thus manufactured so as to have a double cylinder structure
including the inner and outer cylinders. The inner cylinders 10A, 10B of the traversing
drum 1 are externally fitted over two bearings 5A, 5B fixedly installed on the different-diameter
step portion of the rotating shaft 2. An end surface plate 13 extending in an inner
radial direction of the traversing drum 1 is fixed screws 14 or the like to a disk
portion of a drum wheel 12 fixed to the tip of the rotating shaft 2 (its left end
in Figure 1) via a set screw 11.
[0014] The traversing drum 1 is configured in this manner, then so it is composed of a ceramic
burned member and thus has a very small mass. It also serves to reduce loads on a
drum motor 4, which thus has significantly reduced power consumption. It is also possible
to extend the lifetime of the drum motor 4 itself. Furthermore, the groove bottom
of the guide groove 8 in the traversing drum 1 and the inner cylinders 10A, 10B as
a bearing supporting portion are integrally connected together. This makes it possible
to increase the rigidity of the whole traversing drum 1 including the outer cylinder
9.
[0015] Figure 2 shows a second embodiment of the present invention. In a traversing drum
15, shown in Figure 2, an inner cylinder 16 is molded of a single continuous cylinder.
An outer cylinder 17 is formed integrally with the inner cylinder 16 at one end of
it. Further, as in the case with the traversing drum 1 shown in Figure 1, the other
end of the outer cylinder 17 is fixed to the disk portion of the drum wheel 12 via
screws 14 or the like. Accordingly, the drum as a whole has a high rigidity, so that
the groove bottom of the guide groove 8 and the inner cylinder 16 are not integrally
connected together. The other arrangements, operations, and effects are the same as
those of the first embodiment.
[0016] Figure 3 shows a third embodiment of the present invention. A traversing drum 18
according to this embodiment is a combination of the first and second embodiments.
Specifically, the inner cylinder 16 is molded of a single continuous cylinder. The
outer cylinder 17 and the inner cylinder 16 are integrated together at one end of
them. The groove bottom of the guide groove 8 and the inner cylinder 16 are integrally
connected together. Consequently, the traversing drum 18 according to this embodiment
has an increased rigidity because the inner cylinder 16 and the outer cylinder 17
are integrally molded at one end of them and because the groove bottom of the guide
groove 8 and the inner cylinder 16 are integrally molded. Therefore, the traversing
drum 18 as a whole has an excellent rigidity. The other arrangements, operations,
and effects are the same as those of the first embodiment.
[0017] The traversing drums according to the first to third embodiments are each composed
of a ceramic burned member. The ceramic burned member has a thermal expansion coefficient
different from that of the rotating shaft 2, made of metal. Thus, as an operation
time elapses, the heating of the drum motor 4 makes a difference in thermal expansion
between the traversing drum and the rotating shaft 2. This may reduce the coupling
intensity between the traversing drum and the rotating shaft 2. Thus, as shown in
Figure 4, rubber rings 19 are installed on the outer peripheral surface of the bearings
5A, 5B to support the traversing drum, made of ceramics, via the rubber rings 19.
This serves to absorb the difference in thermal expansion caused by the difference
in material.
[0018] The present invention is not limited to the above described embodiments but may be
changed properly. For example, the inner cylinder 16 and the outer cylinder 17 may
be integrally connected together at a position other than the groove bottom of the
guide groove 8.
[0019] As described above, according to the present invention, the drum main body of the
traversing drum, used in an automatic winder or the like, is integrally molded of
a ceramic burned member. Consequently, a traversing drum can be manufactured which
is lighter than conventional ones, which are made of metal. It is thus possible to
reduce the power consumption of the rotative driving source for the traversing drum
and to extend the lifetime of the rotative driving source.
[0020] Further, in the present invention, the traversing drum is composed of the double
cylinder including the inner cylinder and the outer cylinder. Furthermore, the inner
cylinder and the outer cylinder are integrally molded of a ceramic burned member.
Consequently, a traversing drum can be manufactured which is rigid and light even
if it is thin. It is thus possible to significantly reduce the power consumption of
the rotative driving source for the traversing drum and to extend the lifetime of
the rotative driving source.
[0021] Moreover, in the present invention, the inner cylinder and the outer cylinder are
intermittently connected together using the ribs. This makes it possible to further
improve the rigidity of the traversing drum.
[0022] Further, in the present invention, the ribs are used to connect the groove bottom
of the guide groove formed in the surface of the outer cylinder and the inner cylinder
together. This makes it possible to further improve the rigidity of the traversing
drum made of ceramics and composed of the double cylinder including the inner and
outer cylinders.
[0023] Furthermore, in the present invention, the inner cylinder is installed over the rotating
shaft via the bearings having the rubber rings installed on their outer peripheral
surfaces. It is thus possible to absorb a difference in thermal expansion based on
a difference in material between the rotating shaft (metal) of the rotative driving
source and the traversing drum, made of ceramics. This prevents, for example, a failure
to transmit a rotative driving force owing to a possible gap between the rotating
shaft and the traversing drum.
1. A traversing drum which drives a winding package while being in surface contact with
the winding package and which has an endless track like guide groove formed in an
outer peripheral surface of the traversing drum to traverse a yarn in a lateral direction,
the traversing drum being characterized in that a drum main body including the groove is integrally molded using a ceramic burned
member.
2. A traversing drum characterized in that a drum main body is composed of a double cylinder including an inner cylinder and
an outer cylinder which are integrally molded using a ceramic burned member.
3. A traversing drum characterized in that a drum main body is composed of a double cylinder including an inner cylinder and
an outer cylinder which are integrally molded using a ceramic burned member and which
are intermittently connected together using ribs.
4. A traversing drum characterized in that a drum main body is composed of a double cylinder including an inner cylinder and
an outer cylinder which are integrally molded using a ceramic burned member, and ribs
are used to connected the inner cylinder to a groove bottom of a guide groove formed
in a surface of the outer cylinder.
5. A traversing drum characterized in that a drum main body is composed of a double cylinder including an inner cylinder and
an outer cylinder which are integrally molded using a ceramic burned member, and the
inner cylinder is installed over a rotating shaft via bearings each having rubber
rings installed on its outer peripheral surface.