WO1999028709A1

WO1999028709A1 - Equipment for dosing and applying solvents, adhesives and similar

Info

Publication number: WO1999028709A1
Application number: PCT/EP1998/006759
Authority: WO
Inventors: Sergio Lodi
Original assignee: Tecna Di Sergio Lodi
Priority date: 1997-11-26
Filing date: 1998-10-24
Publication date: 1999-06-10
Also published as: ITMO970217A1; ITMO970217A0; AU1557399A; IT1296766B1

Abstract

The present invention relates to an equipment for dosing and applying solvents, adhesives and similar at the ends of elongated elements and, in particular, tubular pieces of the type especially but not exclusively used in the medical field, comprising a main body (11) fitted with an internal housing (12) ending outside through an access opening (28) and suitable for containing a given quantity of fluid, like solvent, adhesive or similar, placed in a tank (15) connected with the housing. A dosing rotating body (13) is mounted in the housing (12) in such a way that it revolves freely and is provided with a peripheral skirt (24) on which a plurality of groups of through holes (25) positioned at an angular distance is obtained, at least one of which is submerged in the fluid. When inserting a small pipe in the access opening (28), a motor (14), connected to a presence detector, activates the dosing rotating body (13) for a rapid series of oscillations or vibrations, and, upon extraction of the small pipe, it activates the dosing rotating body (13) for a predetermined angular width so that the groups of holes (25) can be subsequently submerged in the fluid facing the access opening (28).

Description

Equipment for dosing and applying solvents, adhesives and similar.

Technical Field The present invention relates to an equipment for dosing and applying solvents, adhesives and similar.

Background Art As is known, in various technical fields and, in particular although not limited to, the field of medical equipment and products, there is a need to assemble piping systems comprised of tubular pieces connected, with adhesives, to joints, branches, fittings .and similar. The assembling operations are usually carried out manually, by dampening the ends of the tubular pieces with an adhesive or solvent of a known type, which must be compatible with the materials to be glued and with the final use of the pipes. A solvent of a known type widely used in this field is cyclohexanone, whose positive features are unfortunately combined with a pungent and unpleasant odour and with still unknown effects on the health of the operators carrying out the gluing process.

In this field, therefore, forced suction systems for the extraction of solvent fumes from the working areas have become necessary. Along with these systems, equipment reducing to a πuriimum the operators' exposure to solvent fumes have also been installed, thus helping the dosing of the solvent at the ends of the small pipes to be glued. The main drawback of the equipment of a known type used for such a purpose was of not providing for a constant and uniform distribution of the solvent at the ends of the small pipes. Another drawback of the equipment of a known type is that they .are not suitable for the application of solvents at the ends of small pipes with a different diameter.

Disclosure of Invention

The aim of the present invention is to overcome the drawbacks of the prior art technique, providing an equipment of the kind mentioned in the preamble of the present description which is easy and cheap to build, to use and to maintain.

In order to reach the aforementioned aim, the invention relates to an equipment for dosing and applying solvents, adhesives and similar, bearing the features illustrated in the following claims. Further characteristics and advantages of the present invention will better emerge from the detailed description of a preferred embodiment that follows, in the form of a non limiting example, with particular reference to the figures of the accompanying drawings, in which: figure 1 is a longitudinal section of an embodiment of the present invention according to line I-I of figure 2; figure 2 is a transversal section of the same according to line II-II of figure 1. With reference to the figures, an equipment 10 for dosing and applying solvents, adhesives and similar, is comprised of a main body 11 with a housing 12 for a dosing wheel 13 driven by a motor 14, which is preferably but not exclusively an electric step motor. To the main body 11 is connected a tank 15 which is closed at the top by a topping up plug 16 and fitted with an outlet plug 17 and a window 18 for checking the level of the solvent, adhesive or similar. The tank 15 is connected to the housing 12 by a duct 19. The dosing wheel 13 comprises a substantially horizontal central shaft 20, splined onto the driving shaft 21 of the motor 14 and supported, during its rotary motion, by bearings 22. From the central shaft 20 a thin disk 23 stretches radi-ally supporting a peripheral skirt 24 on which groups of radial through holes 25 are obtained at pre-established 90° radial intervals, as shown by the example in the figures. Preferably, each group of holes 25 comprises one or more transversal rows of holes with different diameter, respectively 25a, 25b and 25c, for the application of the solvent or of the adhesive at the ends of pipes with a different diameter. On a side 26 of the main body 11, a door 27 is mounted so as to be mobile from a closing position to an opening position (highlighted with a broken line 27a in figure 2) of an access window 28 wide enough to permit the insertion of one end of a small pipe in one of the holes 25 positioned near the side 26 of the main body 11. An enabling sensor (not illustrated in the figures) is positioned near the access window 28 or, in any case, in the vicinity of the side 26 of the main body 11 , in order to detect the presence of a small pipe inside the window 28 and/or of an operator's hand in proximity to side 26. The sensor sends a presence signal to a control circuit activating the motor 14. On the main body 11 an exhaust duct 19 is provided for, which connects the housing 12 to the outside, preferably by means of a device suctioning the solvent or adhesive fumes contained in the equipment 10.

When using the equipment 10 for dosing and applying solvents, adhesives and simile, the fluid contained in the tank 15 flows into the housing 12 of the main body through the duct 19, thus dampening the lower part of the wheel 13 and filling the through holes 25 placed in proximity to the bottom of the main body 11. Following the activation of the motor 14 (more detailed description of which follows later), the wheel 13 carries out subsequent rotary motions in the direction of arrow R, these having a regular width equal to the angular distance between the group of holes 25. Therefore, for each rotation of the wheel 13 a new group of holes 25 is submerged in the fluid, whereas the group of holes 25 already dampened by the fluid are progressively taken towards the operating position in which they face the access window 28. In the intermediate positions between the lower position, in which the group of holes are submerged in the fluid, and the operating position, the excess fluid can drip in the through holes 25 and so be collected, once again, in the lower part of the housing 12. To dampen the end of a small pipe to be glued, an operator only has to open the cap 27 and insert said pipe end in the hole 25 with a corresponding di.ameter through the access window 28. Each time a small pipe is inserted via the access window 28 and detected by the enabling sensor, the control circuit activating the motor 14 makes the pipe carry out a series of fast oscillations or vibrations which are transmitted to the wheel 13 and, therefore, to the through holes 25. Said oscillations are moderate, i.e. of about one millimetre, and can be easily obtained if the motor 14 is a step motor. In this case, in fact, the operator only has to set the motor 14 for one single step forward and backward with respect to the neutral position in which the hole 25 would be perfectly centred in front of the access window 28. It has been noticed that said oscillations or vibrations help the operator insert the small pipe into the hole 25, as well as enhancing the even distribution of the adhesive at the end of the pipe itself. On then extracting the small pipe from the access window 28, an operation which is always detected by the enabling sensor, the control circuit makes the motor 14 carry out a rotary motion in the direction of arrow R to position new holes 25 dampened by the fluid in front of the window 28. In the easiest case, the door 27, manually activated, is opened at the beginning of the equipment use shift and closed again only at the end of the shift. A further embodiment of the example illustrated in the figures can obviously be envisaged, in which the door 27 is provided with an automatic opening and closing device, this also being controlled by the same circuit controlling the motor.

Further embodiments of the example illustrated in the drawings can be envisaged, all falling within the .aim of the present invention and easily detectable by and feasible for a skilled technician, once the general idea lying behind the solution of the present invention as described above has been clearly understood. For example, the control circuit activating the motor 14 can be activated not only following the enabling signal sent by the presence detector, once the small pipe has been extracted from the window 28, but also at set intervals for example by means of a timing circuit, so as to avoid a prolonged stop of the wheel 13 causing excessive dripping of the fluid from the holes 25 and the subsequent decrease of the fluid quantity introduced by the operator through the group of holes 25 facing the access window 28. A further embodiment consists in varying the angular interval between the groups of through holes 25. Furthermore, the holes 25 positioned on the peripheral skirt 24 can also have shapes which are not circular in order to be adapted to the small pipes with corresponding polygonal or irregular sections. In addition, the shape and/or size of the groups of holes 25 can vary along the whole arch of the peripheral skirt 24 if a repetitive work cycle has been set which envisages the following gluing of small pipes which have a different shape and/or size. According to a further embodiment of the present invention, through holes parallel to the central shaft 20 of the wheel 13 can be made, a selection of which are accessible from the outside by means of an access opening on the side of the main body 11 perpendicular to the central shaft of the wheel 13. Another preferred embodiment envisages the creation, on the peripheral skirt 24, of openings of equal size, which can be circular, polygonal or any other shape, within which removable bushes having through holes of a predetermined diameter can be mounted, whose function is the same as that of the holes 25 previously described with reference to the drawings. In this way, the bushes can be easily replaced with bushes bearing through holes with a different inside diameter, thus simplifying the use of the equipment which is the subject of the present invention in the application of solvent or adhesive to the corresponding ends of pipes with different diameters. A further embodiment of the present invention consists in making a thread or a helical groove or, in any case - generally speaking - one or more folds on the internal surface of the dosing holes. Experiments have shown that through said folds an optimal distribution of the adhesive at the ends of the pipes can be obtained, with neither dripping nor spots. It is also possible to provide the equipment which is the subject of the present invention with a level sensor, placing it in the seat of the wheel 13 in order to constantly control the level of the solvent or of the adhesive inside the housing 12. This makes it possible to have an alarm signal if the level of solvent or adhesive falls below a predetermined limit, and also to control an external pump for extracting, when needed, the necessary quantity of solvent or adhesive from any external container, thus exceeding the possible capacity limits of the integrated tank 15. The main advantage of the present invention is that the opening access 28 is extremely reduced so as to limit the operator's exposure to the solvent or adhesive fluid fumes contained inside the equipment. A further advantage of the present invention is represented by the possibility of carrying out rapidly a high number of gluing operations of small pipe ends. At the same time, it grants an optimal distribution of the fluid at said ends thanks to the vibrations transmitted onto the wheel .after the ends have been inserted. A still further advantage of the present invention, giving a rapid and perfect execution of sequential gluing cycles also for small pipes with a polygonal or irregular section, consists in the possibility of customising the through holes belonging to the same group and each group of holes distributed around the skirt 24 of the wheel 13, either making them directly on the wheel 13 or by using interchangeable dosing bushes. A further advantage of a preferred embodiment of the present invention is the possibility of using any external container, in the place of the tank 15, connected to an external filling pump in order to reduce the size of the equipment which is subject of the present invention, to simplify the solvent or adhesive reloading operations and obtain a more uniform dosing of said solvent or adhesive. Obviously, by mamtaining the principle of the present invention, various embodiments are possible and the relevant details can be varied widely with respect to this description and its illustration without falling outside the field of the present invention.

Claims

Claims.

1. An equipment for dosing and applying solvents, adhesives and similar at the ends of elongated elements and, in particular, tubular pieces, characterised in that it comprises:

- a main body (11) equipped with an internal housing (12) ending outside through an access opening (28) and suitable for containing a given quantity of fluid, like solvent, adhesive or similar, a dosing rotating body (13) mounted in the housing (12) in such a way that it revolves freely and fitted with a plurality of groups of through holes (25) positioned at an angular distance, each comprising at least one through hole (25a, 25b, 25c), at least one of which is a of a known type, submerged in the fluid, a motor (14), connected to a dosing rotating body (13), to rapidly activate the rotary motion of said body for a predetermined angul-ar width, so that the groups of holes (25) can be subsequently submerged in the fluid facing the access opening (28), sensory means to detect the presence or the vicinity of one end of an elongated element in the access opening (28 and/or of the operator's hand and to activate the motor (14) following the insertion, the extraction or the removal of said end from the access opening (28).

2. An equipment as in claim 1, characterised in that it comprises a closing cap (27) for the access opening (28).

3. An equipment as in claim 1, characterised in that it comprises a timing circuit to activate the motor (14) at set intervals also in the absence of a signal from the sensory means.

4. An equipment as in claim 1, characterised in that it comprises a tank (15) for containing the fluid, fixed to the main body (11) and connected to the housing (12) of the dosing rotating body (13).

5. An equipment as in claim 1, wherein the motor (14) is an electric step motor.

6. An equipment as in claim 1, wherein the dosing rotating body (13) comprises a peripheral skirt (24) on which radial through holes (25) are obtained.

7. An equipment as in claim 1. wherein the dosing rotating body (13 comprises a peripheral skirt (24) on which axial holes (25 are obtained.

8. An equipment as in claim 6, wherein each group of holes (25) comprises a plurality of holes (25 a, 25b, 25 c) with different shape and/or size.

9. An equipment as in claim 1, wherein the peripheral skirt (24) bears holes with the same diameter and whatever shape, on which removable bushes are mounted with different internal diameters.

10. An equipment as in claim 1, wherein on the internal surface of the dosing holes threads or hehcal grooves or, in any case, folds are obtained.

11. An equipment as in claim 1, characterised in that it comprises a level sensor in the seat of the rotating body (13) connected to an electronic control circuit.

12. An equipment for dosing and applying solvents, adhesives and similar at the ends of elongated elements, in particular, tubular pieces, characterised in that it comprises: a main body (11) fitted with an internal housing (12) ending outside through an access opening (28) and suitable for containing a given quantity of fluid, like solvent, adhesive or similar, a dosing rotating body (13) mounted in the housing (12) in such a way that it revolves freely and comprising fluid application means (25a, 25b, 25c), a motor (14), coupled with the dosing rotating body (13), to activate selectively an oscillation or a vibration of a predetermined angular width around a neutral position in which the application means face the access opening (28), sensory means to detect the presence or the vicinity of one end of an elongated element and/or of the operator's hand in the access opening (28) and to activate the motor (14) following the insertion, the extraction or the removal of said end from the access opening (28).

13. A procedure for dosing and applying solvents, adhesives and similar fluids at the ends of elongated elements, in particular tubular pieces, comprising the following phases: a) preparation of an equipment comprising at least a tank for containing said fluids, fluid application means mounted on the equipment in such a way that they revolve freely, and driving means to selectively activate the motion of said application means; b) preparation of an elongated element on which said fluids are to be applied; c) approach of the elongated element to the fluid application means; d) transmission, through the driving device, of a vibration to the fluid application means.