Patent Application
20120234237
1. Field of the Invention
This invention relates to a coating machine for coating fiber yarns.
2. Description of the Related Art
Referring to
When the fiber yarn 100 passes the tank 12, it is coated with the plastisol 101. When the fiber yarn 100 passes through the molding die 13, the thickness of the plastisol 101 coated on the fiber yarn 100 is adjusted. Thereafter, the coated fiber yarn 100 is set in shape using the heating device 14, and then, is collected using the yarn pick-up device 15.
Taiwanese Patent No. 1332042 discloses a method for coating a fiber yarn 100 (a glass fiber yarn) using a pellet extruder 16 (see
Moreover, after the coated fiber yarn 100 leaves the pellet extruder 16, it is guided and pressed by a roller 17 to be cooled in a cooling water tank 13. Because the coated layer on the fiber yarn 100 is not completely cured, the pressure from the roller 17 will deform the coated fiber yarn 102, resulting in an elliptical cross-section, as shown in
On the other hand, when the fiber yarn 100 passes through the molding die 13 in the conventional coating machine 1 or in the pellet extruder 16, friction between the molding die 13 and the fiber yarn 100 may result in wear of the molding die 13. In order to lengthen the life of the molding die 13, the molding die 13 is usually made of platinum or diamond. Therefore, the coated fiber yarn 100 made by a conventional method or a conventional machine 1 has a relatively high cost.
Therefore, an object of the present invention is to provide a coating machine for coating fiber yarns that can overcome the aforesaid drawbacks associated with the prior art, and that has improved production efficiency and availability.
Accordingly, a coating machine for coating fiber yarns of this invention comprises:
a yarn supply device to supply at least one fiber yarn;
a coating device including a tank for receiving a coating material, a drum rotatably disposed in the tank, and at least one annular groove formed circumferentially in an outer surface of the drum for receiving the fiber yarn and the coating material and for coating the fiber yarn with the coating material;
a thickness adjuster disposed downstream of the coating device, and including an adjuster support and at least one adjusting die mounted movably to the adjuster support, the adjusting die including a through hole for passage of the coated fiber yarn, the through hole having an upstream inlet end and a downstream outlet end and being tapered from the upstream inlet end to the downstream outlet end;
a shape-setting device disposed downstream of the thickness adjuster for setting the shape of the coated fiber yarn, the shape-setting device having a heating unit controllable to operate at a predetermined temperature for heating the coated fiber yarn;
a cooling device disposed downstream of the shape-setting device for cooling the coated fiber yarn; and
a yarn pick-up device disposed downstream of the cooling device for collecting the coated fiber yarn.
Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments of the invention, with reference to the accompanying drawings, in which:
Before the present invention is described in greater detail with reference to the accompanying preferred embodiments, it should be noted herein that like elements are denoted by the same reference numerals throughout the disclosure.
Referring to
The yarn supply device 21 supplies a plurality of fiber yarns 200. In the preferred embodiment, the yarn supply device 21 includes forty bobbins 211 to supply forty fiber yarns 200.
Referring to
Referring to
As shown in
In each of the adjusting dies 232, the surrounding wall 233 includes an upstream section that has the upstream inlet end 236 and that forms a first truncated conical surface 238, and a downstream section that has the downstream outlet end 237 and that forms a second truncated conical surface 239 coaxial with the first truncated conical surface 238. The downstream section is longer than the upstream section. An included angle defined between the first truncated conical surface 238 and an axis (X) of the surrounding wall 233 is greater than that defined between the second truncated conical surface 239 and the axis (X) of the surrounding wall 233.
The shape-setting device 24 is disposed downstream of the thickness adjuster 23 for setting the shape of the coated fiber yarns 200, and includes a heating unit 241 and a monitor 242. The heating unit 241 is controllable to operate at a predetermined temperature for heating the coated fiber yarns 200. The monitor 242 is used to control the heating unit 241.
The shape-setting device 24 also includes a mechanism (not shown) that can be controlled to move the coated fiber yarns 200 within the shape-setting device 24 at a predetermined speed. Preferably, the mechanism moves the coated fiber yarns 200 at a speed of 3 msec. The heating unit 241 can heat the coated fiber yarns 200 to a temperature ranging from 0° C. to 300° C. to cure the coating material coated on the fiber yarns 200. Preferably, the coated fiber yarns 200 are heated to a temperature ranging from 150° C. to 300° C.
Although the coating machine 2 in this embodiment is exemplified for coating forty fiber yarns 200, it can be configured for coating a single fiber yarn 200.
The cooling device 25 is disposed downstream of the shape-setting device 24 for cooling the coated fiber yarns 200, and includes an air cooler 251, a diameter detecting member 252 for detecting a diameter of each of the coated fiber yarns 200, and a cooling gas ejector 253 disposed downstream of the air cooler 251. After passing the cooling device 25, the coated fiber yarns 200 are transported to the yarn pick-up device 26. In this embodiment, the air cooler 251 includes a water-cooled fan, and the cooling gas ejector 253 includes a condenser.
The yarn pick-up device 26 is disposed downstream of the cooling device 25 for collecting the coated fiber yarns 200, and includes a plurality of bobbins 261, a transport roller assembly 260, and a yarn breakage detector 264. The bobbins 261 are spaced apart from each other, and are used for respectively collecting the coated fiber yarns 200 from the cooling device 25. The transport roller assembly 260 is used for transporting the coated fiber yarns 200 from the cooling device 25 to the bobbins 261, and includes a transport roller 262 having an axial flow passage 263 for permitting a coolant to flow therethrough. The yarn breakage detector 264 is disposed between the cooling device 25 and the transport roller assembly 260.
Referring to
In this embodiment, the method is conducted using the coating machine 2 described above.
Referring back to
In the step 32, the coated fiber yarns 200 are guided to enter the respective through holes 234 of the adjusting dies 232 at the upstream inlet ends 236. The excess coating material is removed from the coated fiber yarns 200 when the coated fiber yarns 200 exit the downstream outlet ends 237 of the respective adjusting dies 232, thereby adjusting the thickness of the coating material on the fiber yarns 200.
Referring to
In the cooling step 34, the coated fiber yarns 200 are cooled by passing through the air cooler 251 and the cooling gas ejector 253 in sequence. Thereafter, the coated fiber yarns 200 are transported to the yarn pick-up device 26. Since the coating material on the fiber yarns 200 is hardened by the heating unit 241, and then cooled by the air cooler 251 and the cooling gas ejector 253 through a direct contact with cooling air and gas, the present invention eliminates the problem of deformation experienced in the prior art shown in
The diameter detecting step 35 is conducted by detecting the diameter of each of the coated fiber yarns 200 using the diameter detecting member 252, and is conducted simultaneously with the cooling step 34. In the yarn breakage detecting step 36, whether or not each of the coated fiber yarns 200 breaks is detected using the yarn breakage detector 264. The yarn collecting step 37 is conducted by transporting the coated fiber yarns 200 that have been treated by the cooling step 34 to the bobbins 261 through the transport roller assembly 260, followed by collecting the coated fiber yarns 200 using the bobbins 261. By the above steps, the method for coating the fiber yarns 200 can be conducted more smoothly to improve production efficiency and availability.
In addition, the annular grooves 223 are divided into first and second groups. The first group of the annular grooves 223 is used to conduct a coating operation on the fiber yarns 200 initially fed by the yarn supply device 21. The second group of the annular grooves 223 is used to repeat the coating operation on the fiber yarns 200 that have been coated in the first group of the annular grooves 223. The returning device 27 is operative to return at least one of the fiber yarns 200, which has been coated in one of the annular grooves 223 of the first group and which has been cooled by the cooling device 25, to one of the annular grooves 223 of the second group to repeat the coating operation.
In the diameter increasing step 38, the coated fiber yarns 200 that have been treated by the steps 31-35 are returned to the coating device 22 using the returning device 27. Thus, the coated fiber yarns 200 can be coated again with the coating material to have an increased diameter.
In particular, the coating machine 2 is operative for coating forty fiber yarns 200. The coating device 22 includes eighty annular grooves 223 which are divided into the first group of forty annular grooves 223 and the second group of forty annular grooves 223. Furthermore, the thickness adjuster 23 includes eighty adjusting dies 232, each of which is aligned with one of the annular grooves 223.
Therefore, the coating step 31 and the diameter increasing step 38 can be conducted simultaneously by the coating device 22 without interference therebetween.
Besides, since the diameter increasing step 38 is used to repeat coating of the coated fiber yarns 200, the fiber yarns 200 can be provided with a required coating thickness as desired. With the use of the diameter increasing step 3B, it is possible, to prevent the fiber yarns 200 from being overly coated in one time with an excessively thick coating layer, which can lead to difficulties in subsequent hardening and/or cooling of the coating material.
While the present invention has been described in connection with what are considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretations and equivalent arrangements.
