FR2575207A1 - METHOD AND DEVICE FOR THE AUTOMATIC EXTRUSION OF MASTIC OR GLUE - Google Patents

Abstract

FOLLOWING THE INVENTION, THIS PROCESS CONSISTS OF SPRAYING A PRODUCT SUCH AS MASTIC OR GLUE, IN THE FORM OF A JET, UNDER THE FOLLOWING CONDITIONS: - A VARIABLE PROJECTION DISTANCE, LIKELY TO EXCEED 400MM; -FOLLOWING A VARIABLE PROJECTION ANGLE, LESS THAN 90; - UNDER A VARIABLE PROJECTION PRESSURE, LIKELY TO EXCEED 200BARS; -AND WITH A VARIABLE, ESPECIALLY HORIZONTAL, PROJECTION POSITION. APPLICATION IN PARTICULAR TO THE AUTOMATIC DEPOSITION OF CORDS OF SEALANT ON MOTOR VEHICLE DOORS.

Description

1-_

  METHOD AND DEVICE FOR THE AUTOMATIC EXTRUSION OF

MASTIC OR GLUE.

  The present invention relates to a method of automatic extrusion of a product such as putty or glue jet or spray, and a device for carrying out this method. It relates more particularly to such a method and such a device which are simple and which allow, on an automatic application station, to greatly improve the quality of the deposited cord.

  reducing the duration of the projection cycle.

  For this purpose, the invention relates to a. automatic extrusion method of the product such as putty or glue which consists, according to an essential particularity, in projecting this product in the form of a fine jet, under the following conditions: - at a variable projection distance, capable of exceed 400 mm; - at a variable projection angle, less than 90 (between the normal to the t8le and the projection axis); - under a variable projection pressure, likely to exceed

  - And with a variable projection position, including horizontal.

  According to the conventional technique, the mastic or adhesive bead is generally extruded at a constant distance of about 20 mm, at a zero extrusion angle (perpendicular to the sheet) and

  with a vertical extrusion position.

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  According to the invention, the remote projection technique advantageously reduces the number of axes of the station.

application such as a robot.

  In addition, the high projection pressure which may exceed 200 bar (approximately 40 in normal extrusion), flattened the deposited cord and

  improves its adhesion on the greasy sheet and on the "raised edges".

  According to another feature of the invention, the fine jet of mastic or glue is projected - with a variable rate of removal, likely to exceed 60 m / min; - and with a presence check of the projected product, notably by means of an optical fiber detector, with a view to

  automatic uncorking with internal circulation.

  The projected cord is deposited at a speed limited by that of the robot, at least twice as fast as that of the usually extruded bead, which provides a significant saving in cycle time. Presence control of the projected product, which is not generally performed for conventional extrusion, greatly improves the quality of the deposited bead by removing the "rat tails" and

cord cuts.

  Other features and advantages of the invention will appear more

  clearly on reading the following description of a mode of

  preferred embodiment, given by way of non-limiting example with reference to the accompanying drawings in which: - Figure I 'is an axial partial sectional view of a device according to the invention; 49398! 1 t676 -3- - Figure 2 shows a left view in axial partial section

  of the device illustrated in FIG.

  The invention therefore proposes a method of automatic extrusion of a bead of mastic or glue which makes it possible to considerably improve the quality of removal. In accordance with this method, a fine putty jet is projected respecting the following various parameters - a variable projection distance, likely to exceed 400 mm, - a variable projection angle, less than 90, - a variable projection pressure, capable of to exceed 200 bar, - a variable projection position, for example horizontal, - a variable speed of removal, likely to exceed 60 m / min, limited by the speed of the robot that projection of mastic effected with an indispensable control of presence of the latter at the outlet of the nozzle, with a view to unblocking

automatic with internal circulation.

  A device for carrying out this method is illustrated in FIGS. 1 and 2. It comprises in particular a gun 2 intended to equip a robot arm. This gun has - a body 4 in the form of a cage - a nozzle holder part 6 rotatable inside 1 this body 4 - two inlet ducts 10 and return 12 of the putty, formed inside the body 4;

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  -4- and a projection duct 14 formed inside the room

  nozzle holder 6 and opening into the nozzle 8.

  A spool valve such as a needle valve 16 is disposed in

  upstream of the inlet duct 10 of the sealant.

  The spray gun 2 also comprises a detector 18 for the presence of putty at the nozzle outlet such as a photoelectric glass fiber cell; this is maintained in the axis of projection of the nozzle 8 by means of a support 20 fixed on the nozzle holder part 6. In this case, this support is

  obtained by milling into the same body 4 of the gun.

  The gun also incorporates a heating pencil 22 and a probe of 15

  heating 24 for the setting temperature of the sealant.

  A variable projection angle for a sweep of the putty projection may be obtained by means of a given pendulum motion

to the nozzle holder 6.

  The previously described device operates according to a projection cycle which comprises the following various phases: gun opening 2: the needle valve 16 controls this

  opening to feed the nozzle 8 in the projection position.

- time delay.

  - Fitting of the optical fibers controlling the presence of the jet of putty during the projection:

  if so, the projection of the sealant continues.

  * in the negative, that is to say in case of plugging of the nozzle & detected by the optical fibers

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  - 5 - - the needle valve 16 controls the closing of the gun for

stop the projection of the sealant.

  - time delay. - The nozzle holder part 6 performs a rotary movement of 90 in unclogging position, by means of a rotary member 26

and a cylinder 28.

- time delay.

  the needle valve 16 controls the opening of the gun.

  - Unclogging delay: a reversal of the circulation of sealant inside the nozzle 8 is operated to the return duct 12. An automatic unclogging in a vacuum or to

  internal circulation is thus achieved.

  - The needle valve 16 controls the closing of the gun.

- time delay.

  the nozzle holder part 6 returns to its initial projection position

turning 90.

  the needle valve 16 controls the opening of the pistol and loop

thus the projection cycle.

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Claims (6)

  1. A method of automatic extrusion of a product such as mastic or glue jet or spray, characterized in that it consists in projecting this product, in the form of a fine jet, under the following conditions - at a variable projection distance, capable of exceeding 400 mm; - according to a variable projection angle, less than 90 (between the normal to the plate and the projection axis) - under a variable projection pressure, likely to exceed bars;   - And with a variable projection position, including horizontal.   2. Automatic extrusion process according to claim 1, characterized in that the fine jet of mastic or glue is sprayed: - with a variable speed of removal, likely to exceed 60 m / min - and with a control of presence of projected product, in particular by means of a fiber optic detector, with a view to   automatic uncorking with internal circulation.   3. Apparatus for carrying out the method according to claim 1 or 2, of the type comprising a gun (2) mounted at the end of a robot arm, characterized in that this pistol comprises a body ( 4) constituting a cage 49398 11676   - 7 - - a nozzle holder part (6) movable inside this body (4) a projection nozzle (8) housed inside this mobile part (6) - two inlet ducts ( 10) and return (12) of the projection product formed inside the body (4); - and a projection duct (14) formed inside the nozzle holder part (6) and opening into the nozzle (8); the nozzle holder part (6) cooperating via a movable member (26) and a jack (28), with the body (4) so as to put in communication * the projection pipe (14) with the inlet duct (10), in the projection position, on the one hand * the projection duct (14) with the return duct (12), as well as the projection orifice of the nozzle (8) with the arrival duct   (10), in the unclogging position, on the other hand.   4. Automatic extrusion device according to claim 3, characterized in that a throttle member such as a spool valve (16) is arranged upstream of the product inlet duct (10). 5. Automatic extrusion device according to claim 3 or 4, characterized in that it incorporates a detector (18) for the presence of product at the nozzle outlet, for example a photoelectric glass fiber cell, maintained in the form of a nozzle. projection axis of the nozzle (8) by   Through a support (20) fixed to the nozzle holder.   6. Automatic extrusion device according to any one of   claims 3, 4 and 5, characterized in that it incorporates a pencil   heater (22) and a heating probe (24) for   temperature of the product to be sprayed. 49398 11676