WO2007003668A1

WO2007003668A1 - Automatic system for the application of a solidifiable fluid

Info

Publication number: WO2007003668A1
Application number: PCT/ES2006/000288
Authority: WO
Inventors: Ginés CLEMENTE ORTIZ; Beatriz PEÑA RUIZ
Original assignee: Index Servicios De Ingenieria, S.L.
Priority date: 2005-07-04
Filing date: 2006-05-24
Publication date: 2007-01-11
Also published as: ES2264892A1; ES2264892B1

Abstract

The invention relates to an automatic system for the application of a solidifiable fluid. The inventive system consists of a robot (1) comprising a head (2) which is controlled by a control module (3) and which is equipped with means for fixing a cartridge (15) containing the solidifiable fluid (4). The invention also comprises means for measuring the displacement speed of the robotic arm (1) in order to control the application of the solidifiable liquid (4) as a function of the instantaneous displacement speed of the robotic arm. In this way, a uniform flow rate of solidifiable fluid is applied along the course of the part (5) to be treated in a reduced time. The solidifiable fluid (4) is preferably of the aeronautical type that is used for sealing. The inventive system can also be used in any other application that requires a sealing fluid to be dosed uniformly onto a part.

Description

AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID

OBJECT OF THE INVENTION

The invention relates to a system that aims to allow the automatic application of a solidifiable fluid.

It is another object of the invention to provide a system that controls the application of the sealant in a homogeneous manner depending on the speed of application.

In general the invention is used for the application of any type of solidifiable fluid and in particular for the application of a preferably aeronautical sealant.

BACKGROUND OF THE INVENTION

In the current state of the art, the application of a solidifiable fluid, such as, for example, a sealing of an aeronautical type or the like, is carried out by means of a manual process in which a sealing fluid consisting of a mixture of products is obtained, which is deposited in a cartridge comprising an application nozzle and a movable base, whose displacement causes the sealant to exit through the nozzle to apply the sealant on the parts to be treated.

This application is done manually in which the displacement of the cartridge base is carried out by means of pressurized air, which determines that both the outlet of the sealant and the movement of the cartridge cannot be effectively controlled, since the application It is governed manually by the operator and as a consequence the deposition is not homogeneous and constant, since both the application flow rate and the distance of the cartridge nozzle from the part on which it is applied vary, which also determines that it is not ensure correct adhesion, by varying the distance between the nozzle and the part, in which case sealant sagging occurs, requiring a second past the sealant to adhere it well to the piece.

In addition, the sealant has the disadvantage that it expires two hours after its preparation, since its attractiveness increases as time goes by, which in manual application forces to dispose of large amounts of sealant when it solidifies before finishing its application.

On the other hand in the state of the art it is known to use robots equipped with a robotic arm that includes a spindle, both of which are governed by a control module to cause their displacement according to a previously established route on the structure of a piece to be treated , which are preferably applied to perform the welding of parts, so these robots can not be used to apply a sealant by not providing a control and mechanism that allows the homogeneous output of a fluid. Therefore, there is currently no technology that allows the application of a sealant on parts.

DESCRIPTION OF THE INVENTION To achieve the objectives and solve the aforementioned drawbacks, the invention provides a system that allows the automatic application of a solidifiable fluid, such as an aeronautical sealant, which is based on the use of a robotic arm. which is provided with a head, these being governed by a control module to cause its displacement according to a previously established route on the structure of the piece to be treated, and which is stored in the control module. In addition, the invention provides for the use of a cartridge in which the fluid is housed, and which comprises a movable base and a nozzle for effecting the application of the fluid. The main novelty of the invention is that the head is provided with means for holding the cartridge and means for linear displacement of the base of the cartridge, whose drive is governed from the control module; further comprising means for measuring the travel speed of the robotic arm to govern the linear travel speed of the cartridge base as a function of the instantaneous travel speed of the robotic arm and to apply a homogeneous flow rate of solidifiable fluid along the travel of the piece to be treated

Therefore, the application of the sealant is automatically controlled by the invention, and all this in such a way that this application of the sealant is carried out in a homogeneous manner depending on the speed of movement of the robotic arm, whereby the correct adhesion of the sealant In addition, this system solves the problem of the expiration of a sealant, since when performing the automatic application it is carried out in a short period of time during which the viscosity of the sealant does not vary, thereby taking advantage of the totality of the sealant. The invention provides that the means for measuring the travel speed of the robotic arm comprise a detector that determines the travel speed of the robotic arm from the control signals generated by the control module to cause the movement of said robotic arm . The speed detector is included in the control module and is connected to a signal converter, which in turn is connected to an input / output module to produce an analog signal proportional to the linear displacement speed of the cartridge base , so that the application of a homogeneous flow of solidifiable fluid on the piece to be treated is governed.

The invention provides for the incorporation of a laser that is connected to the input / output module and that is governed by the control module to detect the center of marks made in the piece to be treated, so that the system knows the exact position of the piece with respect to the head.

In order to perform this functionality, it is also provided that the control module comprises means for calibrating the laser.

It also includes barrier photocells connected to the control module through the input / output module to precisely govern the position of the exit hole of the cartridge nozzle according to the previously established path, so that the nozzle output is always maintained at a fixed distance from the piece, which guarantees the perfect adhesion of the application of the sealant in any part of the piece. In addition, the inclusion of a sensing module that is governed by the control module, to which it is connected through the input / output module, is provided to travel the parts, prior to the application of the solidifiable fluid; including the control module means for detecting the path made by the probe on the parts so that it knows the real path to be performed by the head, the control module being provided with means for comparing the path previously established with the path made by the probe and including the control module means of correction of the path previously established from the path made by the probe, so that the system has greater reliability to always maintain the same distance from the nozzle with respect to the parts at apply the solidifiable fluid which guarantees the perfect adhesion of the application of the sealant in any part of the piece.

In the preferred embodiment of the invention, the linear displacement means of the cartridge base comprise a spindle, which is related to a plunger which presses with the base of the cartridge when applying the fluid, and which is driven by a servomotor whose speed of rotation is governed by the control module through the speed detector and through the analog signal it provides and that is proportional to The measured speed.

To govern the travel of the piston, it is envisaged that the head is provided with elements for detecting the extreme positions of the piston so that the control module knows when it is at the start and end of the stroke.

To carry out the application of the fluid, it is necessary that the cartridge does not contain air inside it, for which the invention provides for the incorporation of manual purging means of the cartridge that actuate the piston to prevent the fluid from being applied at the beginning of the application. form bubbles. For this, the user has to activate the manual purging means of the cartridge which, when the piston is operated, presses the fluid, so that the user has to deactivate the manual purging means when he detects that the fluid starts to flow out of the nozzle. continuously

The invention provides that the control module is provided with means for retracting the piston at the end of the application of the fluid, this being arranged to effect a new application.

The means for holding the cartridge comprise a threaded sheath to avoid deformation of the cartridge by pressing the plunger against the base when the fluid is applied.

For fixing the workpiece, clamping means are provided that keep it in a fixed position during the application of the fluid.

The system of the invention includes a display screen showing the various - G -

operating parameters of the system, as well as a keyboard of system governance by an operator.

In the preferred embodiment the pieces to be treated are of the aeronautical type and the solidifiable fluid is a sealant, an adhesive or combination of both.

In order to facilitate a better understanding of this descriptive report and forming an integral part thereof, a series of figures are attached in which the object of the invention has been shown as an illustrative and non-limiting nature.

BRIEF STATEMENT OF THE FIGURES

Figure 1.- Shows a perspective view of a robot in whose claw a servo-driven dosing head according to the invention is located. Figure 2.- Shows a general block diagram of the system of the invention.

Figure 3.- Shows a perspective view of the head of Figure 1, with the difference that the cartridge and sealant application nozzle has been included by the head.

Figure 4.- Shows a schematic view of the inside of the head to facilitate a better understanding of its operation.

Figure 5.- Shows a possible example of application of the sealant on a piece.

Figure 6.- It shows a front view of the display screen in which the different procedure parameters of the system are shown, together with the operating system control keypad by an operator.

DESCRIPTION OF THE PREFERRED EMBODIMENT The following is a description of the invention based on the figures discussed above.

The invention comprises a robot 1 in whose claw a head 2 for applying a sealant 4 is located on a piece 5 which is governed by the control module 3 of the robot.

The head 2 comprises a servomotor 6 that produces the rotation of a spindle 7 whose angular displacement transmits a linear movement to a nut 8 for which it includes rods 9 that perform the anti-rotation function to prevent the nut 8 from rotating, so that only this can effect a linear displacement when actuated through the spindle 7. Between the servomotor 6 and the spindle 7 there is a reducer 10 and an elastic coupling 11 that produces the union between the spindle 7 and the output of the reducer 10.

In addition, bearings 12 are provided that guarantee the alignments and absorb radial stresses of the assembly determined by the servomotor 6, reducer 10 and elastic coupling 11.

The nut 8 is integral with a rod or piston 13 at the end of which a pusher 14 is provided that performs the function of pressing against the movable base (not shown) of a cartridge 15 containing the sealant 4 for application by means of a nozzle 16.

The head 2 includes an outer sleeve 17 for protecting the spindle mechanism 7.

Inside the jacket 17 two detectors 18 are incorporated which detect the extreme positions of the piston to allow its operation to be governed by the control module 3.

In order to correctly apply the sealant 4, the system comprises a laser device 19 by means of which the center of the marks 20 of the profile 5 on which the sealant 4 is applied is located and measured, so that the part 5 is perfectly positioned from the robot's point of view, as will be commented later. For this, two marks located at the ends of piece 5.

In addition, the system comprises barrier photocells 21 which are used to calibrate the nozzle 16 of the dispenser, that is, so that the robot accurately controls the position of the hole of the nozzle 16 where the sealant exits, as will be explained later.

To allow the control of all the elements described by the control module 3 of the robot, it is connected via an interface 22 to an input / output module 23 to which the laser 19, extreme position sensors 18 of the piston 13, are connected, the probe 25 the photocells 21 and the servomotor 6, the connection of which is made by means of an excitation circuit 24. As already mentioned, the invention carries out the homogeneous application of the sealant 4, for which the control module 3 is provided with means for measuring the travel speed of the robotic arm 1 from the signals generated by the control module to control the movement of said robotic arm. The robotic arm travel speed signal provided by the control module 3 is applied to the interface 22 which converts the received signals so that they can be handled by the input / output module 23, which from said received signals produces a analog signal proportional to the travel speed of the robotic arm.

The analog signal provided by the input / output module 23, is a voltage that is applied to the servomotor 6 through the excitation circuit 24 to govern its rotational speed and consequently the linear displacement speed of the plunger 13.

So that the head 2 can apply the sealant 4 on the piece 5, it is introduced into the control circuit 3 a program corresponding to the coordinates of all the points of the path to be followed by the robot to apply the sealant bead on the part 5. Therefore, it is necessary to introduce these coordinates according to the piece on which it should be apply sealant 4.

The control module 3 transforms the existing programs corresponding to the coordinates of each of the pieces 5, to the robot's own language programs to govern its movement according to the structure of the piece 5.

In addition, the input / output module 23 is connected to a probe module 25 which, prior to the application of the sealant and governed by the control module 3, travels over the parts; including the control module 3 means for detecting the actual path that the probe makes on the actual structure of the parts, from the signals provided by the probe, means for comparing the actual programmed path with the actual path and means for correcting the programmed (theoretical) travel according to the actual travel, so as to ensure that the nozzle 16 always maintains the same distance from the parts 5 on which the sealant 4 is applied, so that the user can govern the operation of the system of the The invention provides for the incorporation of a screen 26 and keyboard 27 located on a frame 25, so that on screen 26 the different operating parameters of the system can be visualized, and by means of the keyboard 27 its operation can be governed.

Based on the description made, it is easily understood that in order to carry out the application of a sealant 4 on a piece 5, it is fixed by means of brackets 28 so as to keep it in an immovable position. with respect to the robot 1. Next, the piston 13 of the head 2 is placed in its collected position, as seen in figure 3 (in figure 1 it is represented in its extended position) so that the cartridge is then placed 15 with the corresponding nozzle 16 on the head 2. Obviously the cartridge 15, must be previously filled by the sealant 4, which is composed of different products that are packaged separately, and that are mixed and introduced into the cartridge 15 At this point it is important to point out that the mixture obtained has a limited shelf life since its viscosity increases progressively over time, so that once the shelf life has elapsed, it does not perform its function and must be discarded, a circumstance that The system of the invention does not occur since the application times are very short, less than the useful life of the sealant 4, unlike the manual application that occurred in the state of the technique, so the whole sealant is used. The fixing of the cartridge 15 on the head 2 is carried out by means of threading to avoid deformation of the cartridge by pressing the piston 13 against the base of said cartridge 15 when the application of the fluid 4 is carried out.

Next, the position of the nozzle is calibrated by placing it on the barrier photocells 21 provided in the mooring tool of the part 5 so that the robot performs a calibration of the same in order to carry out the application in a homogeneous way.

Once the nozzle 16 has been calibrated, the robot is removed to a safe position and then the deposition program corresponding to the part 5 on which the sealant 4 is to be applied is selected.

Next, the robot searches for the 20 marks included in the ends of part 5 and calculates their respective -1re¬

positions depending on the structure of the piece, and generates the coordinates of the piece based on the path taken by the probe 25, so that the robot can follow the real trajectory of the piece 5. Before applying the sealant, it is necessary that it does not contain air to allow the homogeneous application of the same, so the robot stops to purge the sealant, an operation that the operator performs through the keypad 27 and indicates it to the control module 3 so that activate the servomotor 6, in the manner described above, until the sealant begins to exit through the hole of the nozzle 16 continuously and without bubbles, at which time the operator causes the stop of the servomotor 6 to cut sealant outlet. Then the robot begins to carry out the homogeneous deposition of the sealant 4 depending on the speed of the robot 1, in the way that was already commented previously and following the profile's own trajectory according to the trajectory calculated from the structure of the piece .

At the end of the application of the sealant 4 the robot 1 is removed to a safe position to allow the removal of the piece 5 and locate a new piece to effect its sealing. While the cartridge 15 does not empty, new applications are carried out in the manner already described, with the proviso that it is not necessary to fix the cartridge 15 when it is already fixed in the head 2.

Through the screen 26 the operator can verify the advance / backwardness of the applicator, and display messages, the value of the analog voltage that is applied, the instantaneous speed of the robot, etc.

Therefore, by means of the system of the invention and depending on the speed of movement of the robot, governs the displacement of the spindle 7 to perform the homogeneous application of a bead of sealant 4 along the part 5 in a short period of time.

Claims

1.- AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, which comprises a robotic arm (1) equipped with a head, governed by a control module to cause its displacement according to a previously established route on the structure of the part (5) a treat, which is stored in the control module (3); the fluid (4) being housed in a cartridge (15) provided with a movable base and an application nozzle (16); it is characterized in that the head (2) comprises means for holding the cartridge and means for linear displacement of the base of the cartridge, whose drive is governed from the control module (3); further comprising means for measuring the travel speed of the robotic arm (1) to govern the linear travel speed of the cartridge base (15) as a function of the instantaneous travel speed of the robotic arm (1) and to apply a rate of homogeneous flow of solidifiable fluid (4) along the path of the part (5) to be treated.

2. - AUTOMATIC SYSTEM FOR THE APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 1, characterized in that the means for measuring the speed of movement of the robotic arm comprise a robotic arm displacement speed detector, from the control signals of the displacement of said robotic arm; the speed detector being included in the control module (3), and connected to a signal converter (22), which in turn is connected to an input / output module (23) to produce an analog signal proportional to the Linear travel speed of the cartridge base.

3. - AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 1 characterized in that it comprises a laser (19) connected to the module input / output (23) and governed by the control module (3) to detect the center of marks (20) practiced on the part (5) to be treated and to know the exact position of the latter with respect to the head (2).

4. AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 3 characterized in that it comprises barrier photocells (21) connected to the control module (3) through the input / output module (23) to precisely govern the position of the nozzle outlet hole (16) of the cartridge (15) according to the previously established path.

5. AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 1, characterized in that it comprises a probe module (25) governed by the control module (3) to which it is connected through the input / output module (23), to tour the pieces; prior to the application of the solidifiable fluid; the control module comprising means for detecting the path made by the probe (25) on the parts (5), means for comparing the path previously established with the path made by the probe (25), and means for correction of the path previously established from the route made by the probe (25); to always maintain the same distance from the nozzle (16) with respect to the parts (5) when applying the solidifiable fluid (4).

6. - AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, according to claims 1 or 2, characterized in that the means of linear displacement of the base of the cartridge comprise a spindle (7) related to a piston (13) that presses against the base of the cartridge ( 15) when applying the fluid (4); and which is driven by a servomotor (6) whose rotation speed is governed by the control module (3) by the analog signal proportional to the measured speed.

7. AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 6, characterized in that the head (2) comprises elements for detecting the extreme positions of the piston (13).

8. AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 6, characterized in that it comprises means for manual purging of the cartridge (15) that actuate the piston (13) to prevent bubbles from forming at the beginning of the application of the fluid.

9. AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 6, characterized in that the control module (3) comprises means for retracting the piston (13) at the end of the application of the fluid.

10.- AUTOMATIC SYSTEM FOR THE APPLICATION OF A FLUID

SOLIDIFICABLE, according to claim 6 characterized in that the means for holding the cartridge (15) comprise a threaded sheath (30) to avoid deformations of the cartridge

(15) by pressing the plunger (13) against the base of said cartridge (15) when the fluid application (4) is carried out.

11. AUTOMATIC SYSTEM FOR THE APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 1, characterized in that it comprises means (28) for holding the piece (5) to be treated to keep it in a fixed position during the application of the fluid.

12. - AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 3, characterized in that the control module (3) comprises means for calibrating the laser (19).

13. - AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 1, characterized in that it comprises a screen (26) for displaying the different operating parameters of the system and a keyboard (27) of system governance by an operator.

14.- AUTOMATIC SYSTEM FOR THE APPLICATION OF A SOLIDIFICABLE FLUID, according to previous claims, characterized in that the parts to be treated are of the aeronautical type.

15. AUTOMATIC SYSTEM FOR APPLICATION OF A SOLIDIFICABLE FLUID, according to claim 13, characterized in that the solidifiable fluid (4) is selected from a sealant, an adhesive and a combination thereof.