MXPA00008578A - Entangling protection arrangement for a thread feeding buffer - Google Patents

Abstract

A thread feeding buffer for feeding a fibre thread (15) from a magazine roll (14) to a feed apparatus at a robot arm which is freely movable in the room. The thread feeding buffer comprises thread brake means (16, 19, 20) and at least one movable thread guide (17), on which a thrust force is acting. The thread is running from the magazine roll (14), via the brake means (16, 19, 20), through the thread guide (17) and further on towards the feed apparatus in such a way, that the thrust force acts for creation of a thread buffer between the brake means and the feed apparatus, which buffer is variable in length. At least one guide rod for guiding the movable thread guide is provided with means arranged to cause a braking effect on downward movement of the movable thread guide for preventing entanglement of the thread fed through the movable thread guide following a rapid fall of said movable thread guide.

Description

ARRANGEMENT OF PROTECTION AGAINST GRINDING FOR TJ FILAMENT FEED REGULATOR FIELD OF THE INVENTION The present invention relates to a filament feed regulator for feeding a fiber filament from a reservoir roll to a feeding apparatus on a robot arm, which can move freely in the room, and of the type which is described in the U.S. patent application No. 08 / 693,155.

BACKGROUND OF THE INVENTION The production of fiber reinforced thermosettable plastic products can be automated by the use of an industrial robot, by means of which a fiber feeding apparatus can be controlled, so that the precise quantities of fiber are fed, which are oriented to maximum strength, without the fibers projecting out through the outer plastic layer of the product. Due to the repetitive capacity of the robot, the quality of these products can be increased considerably, and simultaneously problems related to an inadequate work environment and fatigue to work can be solved.

REF .: 122978 The fiber feeding apparatus is preferably located in a feeding head which can be mounted on a movable robot arm. One or more strands of fibers are supplied to the feed head, which cuts the fibers in suitable lengths. The feeding speed of the fiber filament can be in the range of approximately 10 meters per second. At such feed rates, it is difficult to stop the filament feed without risk of the filament becoming entangled. The characteristics defined in the aforementioned request solve in an efficient manner the problems defined in the above. However, it has shown in itself that some risk of entanglement can still occur when the yoke provided with the movable filament guide moves downward at high speed. When the yoke reaches its lowest position, there may be the possibility that a tangle of fed fiber will be manufactured which may loosen and become entangled.

TECHNICAL PROBLEM The object of the invention is therefore to provide an arrangement in a filament feed regulator which solves the problem described above.

SOLUTION For this purpose, the entanglement protection arrangement for a filament feed regulator for a fiber filament fed from a supply and along a path comprising a first guide for the filament, to receive the filament from the supply, a contacting brake surface on which the filament is fed from the first guide; a movement of brake element within the control with the brake surface for braking movement of the filament passing the brake surface; a movable filament guide in the path of the filament passing the brake surface, a support comprising two guide rods positioned substantially vertical supporting the movable filament guide for movement; an additional guide that follows the movable filament guide in the filament path and past which the filament is stretched; the support allows the movable filament guide to move along the filament to reduce the length of the filament path between the brake element that engages the brake surface and also allows the movable filament guide to move to lengthen the length of the filament path. distance between the brake surface and the additional filament guide to absorb the unstressed part in the filament in the path between the brake surface and the additional filament guide, is characterized in that at least one of the guide rods is provided with a means arranged to cause a braking effect on the downward movement of the movable filament guide to prevent entanglement of the filament which is fed through the movable filament track after a rapid fall of the movable filament guide.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described with reference to a modality shown schematically in the accompanying drawing, in which Figure 1 is a plan view of a filament feed regulator, according to the invention, with a filament guide movable that moves up, and Figure 2 is a corresponding view showing the movable filament guide according to Figure 1 moving downward.

DESCRIPTION OF THE PREFERRED MODALITIES The filament feed regulator according to the drawing comprises a support 10 with two vertical guide rods 11. The support 10 carries an elbow arm 12 with an eyelet 13 for filament, for a filament 15 which develops from a roll 14. The filament may consist of filaments of multiple fibers of glass, carbon fiber or synthetic fibers. The filament eye 13 provides a substantially friction free passage of the filament. The filament runs upwardly from the roll 14 which is located at ground level, through the filament eye 13 and further on a bar 16 which changes the backing direction vertically downwardly between the guide rods 11. A filament guide 17 is movably guided by the guide rods and is provided with additional filament eyelets 13, through which the filament 15 runs. The filament then runs from the filament guide 17 in the upward direction to a filament guide 17. channel 18 of filament guide, which guides the filament additionally to a robot arm, which is not shown. A filament brake cooperates with the bar 16 and is constituted by a clamping plate 19, which is mounted on the outer end of a pneumatic cylinder 20 which is connected to the support 10. The clamping plate can be placed inside or outside of coupling with the bar 16 by operation of the cylinder 20, whereby the feeding of the filament will be stopped. The filament feed regulator operates in the following manner: during normal filament feeding, the pulling of the filament, by means of the filament eyelets 13 and the bar 16, generates a uniform resistance in the filament resulting in a feeding of uniform and advantageous output. If the robot arm moves in the room, so that more or less filament must be fed momentarily, the filament guide 17 will be able to move up and down respectively, along the guide rods, where The filament will receive a quick compensation in the length. If the feeding of the filament is to be stopped, this is done by activation of a pneumatic cylinder 20 which then presses the clamping plate 19 against the bar 16. Now the feeding of the filament at the end of the robot arm will continue for a Brief moment while the filament guide 17 moves upwards along the guide rods 11, until the hauling of the filament is stopped. When it is time to restart the feeding, it will start with a pretensioned filament correctly without risk of curls or twists on the filament. The first of the vertical guide rods 11 of the support 10 at its lowermost end can be moved and is supported in a direction towards and from the opposite vertical guide rod by means of a sphere 21 or the like that can be moved in a groove. 22 transversal. In normal operation, the lower end of the first vertical guide rod 11 is in its neutral position, as shown in Figure 1, where the yoke is provided with the movable threaded guide 17 moving upwards. A means is provided for causing movement of the movably supported lower end of the first guide rod, preferably a drive piston 23, to cause such transverse movement to a rapid downward movement of the yoke of a piston. 23, in order to cause the space between the two vertical guide rods to be reduced so much that the yoke with the movable thread guide 17 is clamped and therefore does not produce any jump. The movement of the yoke is preferably monitored by a sensor 24 and therefore a rapid downward movement of the yoke causes the sensor to emit a signal to activate the pulse piston 23. This sensor is preferably connected to a central unit 25 which receives a signal from the sensor 24, which represents the current velocity of the yoke, whereby the signal is compared with a threshold value in the central unit, whereby the central unit is arranged to allow an output that activates the thrust piston 23 when the detected downward velocity of the yoke exceeds the threshold value. The invention is not limited to the embodiment described above, but various variations are possible within the scope of the appended claims. For example, the guide rods can be exchanged by other means to control a fiber filament regulator. In addition, a spring means can replace the action of gravity on the filament guide means 17. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects or products to which it refers.

Claims (6)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. An entanglement protection arrangement for a filament feed regulator for a fiber filament fed from a supply and along a path comprising a first guide for the filament, to receive the filament from the supply, a contactable brake surface on which the filament is fed from the first guide; a brake element that moves in control with the brake surface for filament braking movement past the brake surface; a movable filament guide in the path of the filament passing the brake surface, a support comprising two guide rods positioned substantially vertical which support the movable filament guide for movement; an additional guide that follows the movable filament guide in the filament path and past which the filament is stretched; the support allows the movable filament guide to move along the filament to reduce the length of the filament path between the brake element that contacts the brake surface and also allows the movable filament guide to move to elongate the filament. distance between the brake surface and the additional filament guide to absorb the unstressed part in the filament on the path between the brake surface and the additional filament guide, characterized in that at least one of the guide rods is provided with a means arranged to cause a braking effect on the downward movement of the movable filament guide to prevent entanglement of the filament fed through the movable filament guide after a rapid fall of the movable filament guide.

2. The arrangement according to claim 1, characterized in that the means arranged to cause a braking effect on the movable filament guide is constituted by a trajectory of movement for the lower end of the first of the vertical guide rods, which allows that the lower end of the guide rod moves slightly towards the other guide rod, so that the distance between the two guide rods at the lower ends thereof is shortened, and in this way cause a braking effect by clamping on the guide of the movable filament when it moves down. - • '- •. ** •

3. The arrangement according to claim 2, characterized in that the path of movement for the lower end of the first of the two vertical guide rods is constituted by a ball bearing track.

4. The arrangement according to claim 2, characterized in that a thrust piston is provided adjacent to the lower end of the first of the vertical guide rods, to allow the lower end of the first guide rod to be pushed towards the other guide rod for cause a braking effect by clamping on the movable filament guide.

5. The arrangement according to claim 4, characterized in that a sensor is provided to detect a rapid downward movement of the movable filament guide, the sensor is arranged to cause the impulse piston to perform a stroke which forces the lower end of the first of the vertical guide rods to move towards the other guide rod, when the sensor detects a rapid downward movement of the movable filament guide.

6. The arrangement according to claim 5, characterized in that a central unit is provided which is adapted to receive a signal representative of the speed of downward movement of the filament guide movable from the sensor, comparing it with a threshold value and providing an output to activate the impulse piston, when the detected speed exceeds a threshold value.