EP1378476A2

EP1378476A2 - Traversing drum

Info

Publication number: EP1378476A2
Application number: EP03014622A
Authority: EP
Inventors: Hidetoshi Roureru Couto Muromachi 310 Kimura; Kenji Muraya; Ichiro Hidaka
Original assignee: Murata Machinery Ltd
Current assignee: Murata Machinery Ltd
Priority date: 2002-07-01
Filing date: 2003-06-26
Publication date: 2004-01-07
Anticipated expiration: 2023-06-26
Also published as: EP1378476B1; DE60309781T2; CN100368274C; EP1378476A3; CN1468795A; JP2004035127A; DE60309781D1; JP3744475B2

Abstract

The present invention provides a traversing drum used in an automatic winder or the like, the traversing drum being made of ceramics and thus having a small mass. A drum main body of a traversing drum 1 used in an automatic winder or the like is composed of a double cylinder including inner cylinders 5A, 5B and an outer cylinder 9. The inner cylinders 5A, 5B and the outer cylinder 9 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 a rotative driving source for the traversing drum 1 and to extend the lifetime of the rotative driving source (Fig. 1).

Description

Field of the Invention

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

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.
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.
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

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.
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.
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.
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.
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

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

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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.

Claims

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.
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.
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.
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.
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.