Background of the Invention
The invention involves a process for the drawing of optical fibers through textiles and a device for the carrying out of the process.
The use of optical fibers in conjunction with textiles for the purposes of illumination and decoration is well-known. To date, however, optical fibers could only be drawn through textiles manually. This process is an extremely time-consuming one and involves much expenditure of work.
Summary of the Invention
An object of the invention is, therefore, to permit the drawing of optical fibers through textiles (woven fabric) by mechanical means, guaranteeing high standards of precision and speed.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the method of drawing an optical fiber through a fabric, having opposite first and second sides, comprises the following consecutive steps: advancing the optical fiber by a fiber transport device in a hollow needle to a predetermined extent; pushing the hollow needle, together with the optical fiber, through the fabric from the first side to the second side until a free end of the optical fiber has traversed the fabric to a predetermined extent; withdrawing the needle from the fabric to the first side thereof while maintaining the optical fiber substantially stationary relative to the fabric; gripping the free end of the fiber by a grasping device on the second side; pulling the optical fiber through the fabric until a predetermined pulled-through length of the optical fiber is obtained on the second side; and severing the optical fiber by a cutting device on the first side.
Brief Description of the Drawing
FIG. 1 is a schematic sectional side elevational view of a preferred embodiment of the invention.
FIG. 2 is a schematic sectional side elevational view of another preferred embodiment of the invention.
Description of the Preferred Embodiments
A preferred embodiment of the invention according to FIG. 1 is made up essentially of the fiber spool (3), the hollow needle (4), the fiber-transport device (5), the grasping device (6), the cutting device (7), the holding-down device (8) and the working platform (9).
The textiles (2) to be processed are fed to the device either from a spool or in ready-cut pieces via the working platform (9). The fabric lies on the working platform with the front side facing downwards.
The hollow needle (4), the fiber-transport device (5), the fiber spool (3) and the cutting device (7) are located underneath the working platform.
The holding-down device (8) and the grasping device (6) are located above the working platform (9) and thus above the reverse side of the fabric.
At the beginning of a working cycle, the end of the optical fiber (1) is located in the hollow needle (4).
The hollow needle is movable in the direction of its longitudinal axis, i.e. "upwards" and "downwards", and is thrust from underneath through an opening provided in the working platform through the fabric (2) lying on it. In the process, the holding-down device (8) prevents the fabric (2) from being raised or shifted. The fiber-transport device (5) then pushes the optical fiber (1) sufficiently far forward in the hollow needle to enable the fiber-end to be gripped by the grasping device (6) as its jaws (6a) move toward one another as indicated by the double-headed arrows A.
After the optical fiber (1) has been gripped by the grasping device (6), the hollow needle (4) is drawn back to the starting position again.
Subsequently, the end of the optical fiber (1) gripped by the grasping device (6) is drawn through to the required length by means of the grasping device (6) as it travels in a direction indicated by the double-headed arrows B, to a predetermined location and deposited there. At the point of penetration of the fabric (2) the fiber is then secured to prevent its slipping out of position, preferably by the use of an adhesive.
After that, the optical fiber (1) is cut between the working platform (9) and the retracted hollow needle (4) by means of the cutting device (7) located underneath the working platform (9) such that a certain length of the optical fiber (1) projects out of the fabric (2), pointing downwards. The grasping device (6) then returns to the starting position above the hollow needle (4).
After the new end of the optical fiber (1), which following cutting still projects slightly out of the hollow needle (4), has been drawn back into the hollow needle (4) completely by the fiber-transport device (5), the device is ready to begin a new working cycle. For this purpose, the device (Part 3-8) advances to the next penetration point in a direction indicated by the double-headed arrow C, with the assistance of suitable guide and drive systems.
Preferably, penetration of the fabric (2) is carried out in a straight line and the optical fibers (1) laid in the direction of this line, so that, at the same time, the fibers at the point of penetration can be secured against slipping out and the remaining fibers laid on this line can be fixed.
According to another preferred embodiment of the invention shown in FIG. 2, the machine is equipped with a hollow needle (4) telescopically movable in a guidance tube (10) and a clamping device (11) located at the lower end of the guidance tube (10) instead of the fiber-transport device (5) of FIG. 1.
After the jaws (11a) of the clamping device (11) have grasped the fiber (1), the clamping device (11), the guidance tube (10) and the needle (4) in its extended state are moved upward, whereby the needle (4) pierces the fabric (2). The device (4, 10, 11) is stopped when the needle (4) is situated between the open jaws (6a) of the grasping device (6). Thereafter the hollow needle (4) is drawn back sufficiently far with the clamping device (11) in a closed position to enable the grasping device (6) to grip the free end of the optical fiber (1), which cannot be drawn back due to the closed jaws of the clamping device (11). The jaws (11a) of the clamping device (11) then open to enable the grasping device (6) to pull the gripped end of the optical fiber (1) on through and deposit it at a certain point as described in connection with the embodiment of FIG. 1.
After this has happened and the optical fiber (1) has been cut underneath the working platform (9) by the cutting device (7) between the working platform (9) and the retracted hollow needle (4), the hollow needle (4) is pushed forward sufficiently far relative to the guidance tube (10) to enable the new end of the optical fiber (1) to enter the hollow needle (4) completely. After that, the device is ready to begin a new working cycle.