Strip applicator with automatic strip arrangement during the filling process and method for filling such an applicator

Description

[0001] The present invention relates to a jointing tape applicator between two plasterboards with automatic strip arrangement during filling, and a method of filling such an applicator.

[0002] A jointing tape applicator is intended for applying a strip of paper or similar material, in the form of a roll, between two adjacent plasterboards, during construction or renovation, using a pasty coating.

[0003] Thus, the plaster fills the space between the two plates and the strip holds everything together.

[0004] The tape is installed between two panels arranged on the same plane or at an angle. Once the plaster and the tape are in place, the user smooths the entire assembly using a flat or angled spatula for corners. The tape thus ensures a perfectly smooth joint between the panels.

[0005] There are two known types of tape applicators.

[0006] The first, commonly called a "bazooka", is illustrated, for example, in document US4105490.

[0007] It comprises a tubular coating conduit connected, in use, to a pump controlled by a trigger carried by the conduit. The latter also comprises at its operational end a dispenser for a roll of jointing tape and a head for applying the tape. In use, the application head unrolls the tape against the plates and the user controls the pump so that it ejects coating under the tape.

[0008] This type of applicator is very bulky and tiring to handle, as a large part is cantilevered. Furthermore, it is constantly connected to the pump throughout use, which makes it difficult to handle and requires carrying the weight of the hose. In addition, it is expensive and complex, because the supply of coating and the unwinding of the strip must be managed during the application of the strip. In this type of applicator, there is no reservoir in which the strip is automatically loaded with coating. Finally, the systematic connection to the pump requires a waterproof connector, to avoid putting coating everywhere, which makes the design complex and fragile, and requires regular maintenance of the joints.

[0009] The second type of tape applicator, commonly referred to as a "banjo" and illustrated, for example, in document US2328571, includes a coating reservoir in which the tape is loaded with coating during application. It also includes a dispenser for a roll of jointing tape for performing numerous joints, particularly on large construction sites.

[0010] For this purpose, the tank has, with reference to the position of use, an inlet slot for the strip arranged between a free end of a rear wall of the tank and a first free end of a lower wall of the tank, and an outlet slot for the strip arranged between a free end of a front wall of the tank and a second free end of the lower wall of the tank.

[0011] To fill the tank, the latter also includes two side walls, one of which constitutes a removable side cover for access to the interior of the tank. The cover can be removable by removal or by pivoting.

[0012] To fill the banjo-type applicators, open the hood, manually place the strip against the rear, top, and front walls, and then fill the space between the positioned strip and the lower surface of the tank with filler.

[0013] This filling operation, which is generally done manually with a plastering knife, is delicate because the plaster must be gently placed, without putting any outside the tank while keeping the strip in the filling position, that is to say against the front, rear and top walls. In practice, this operation is very messy and requires surprisingly a lot of know-how.

[0014] Document US6367534 B1 describes a banjo which has a check valve on its underside.

[0015] An objective of the present invention is therefore to provide a strip applicator which can be refilled quickly and easily, even by a novice user, which limits the risk of soiling during filling and which guarantees optimal and automatic positioning of the strip in the reservoir.

[0016] Another objective of the invention is to provide an applicator that is easy to handle when applying the strip, i.e. lightweight and without any connection pipe to a pump, in use.

[0017] Another objective is to offer an applicator with a simple and robust design, easy to maintain, and limiting the number and complexity of the parts that make it up.

[0018] Another objective of the invention is to provide an applicator ensuring a clean and traceless application, regardless of the position in which the user's hand grips it.

[0019] An objective of the present invention is to provide an application head allowing simple kinetics and handling of passage from the retracted position to the use position, without having to disassemble the entire head.

[0020] According to the invention, the applicator comprises a structure such that it must be filled upside down, i.e. with the bottom wall upwards. By means of such filling, an applicator is obtained whose filling is not only easy and not very messy, but also versatile, i.e. it can be carried out either manually by gravity or with a syringe, or with a pump intermittently connected to the applicator, and this without requiring a sealed connection with the pump by means of a sealed connector. Furthermore, unexpectedly, the upside-down filling allows the strip to be automatically placed perfectly in the filling position, i.e. against the front, rear and top walls, because it is driven by the weight of the coating which prevents twisting of the strip during filling.On the contrary, if the filling were done head up, that is to say the lower wall downwards, not only would a watertight connection with the pump be required, but the strip would risk twisting in the tank and not being positioned correctly, because it would not be carried by the weight of the coating.

[0021] Thus, the invention relates to an applicator for jointing tape between two plasterboards, as defined in claim 1.

[0022] Other particular embodiments are defined in claims 2 to 9.

[0023] The invention also relates to a method of filling an empty jointing tape applicator as defined in claim 10.

[0024] The invention also relates to a method of adding coating in a jointing tape applicator with a coating pump, as defined in claim 11.

[0025] Other characteristics of the invention will be set forth in the detailed description below, made with reference to the appended drawings, which represent, respectively: [ Fig. 1 ] represents a schematic perspective view of a strip applicator according to the invention in the position of use, that is to say in the position for applying a strip; [ Fig. 2 ] represents a schematic perspective view of the tape applicator of the figure 1 and one of the side walls has been raised to show the internal structure of the applicator; [ Fig. 3 ] represents a schematic perspective view of the tape applicator of the figure 1 in the filling position according to the invention, cap closed; [ Fig. 4 ] represents a schematic perspective view of the tape applicator of the figure 1 in the filling position according to the invention, cap open; [ Fig. 5 ] represents a schematic sectional view of the tape applicator of the figure 4 , at the start of filling; [ Fig. 6 ] represents a schematic sectional view of the tape applicator of the figure 4 , being filled; [ Fig. 7 ] represents a schematic sectional view of the tape applicator of the figure 4 , at the end of filling; [ Fig. 8 ] represents a schematic perspective view of a tape applicator according to the invention, and comprising hooks for fixing the applicator in the filling position against a bucket of coating; and [ Fig. 9 ] represents a schematic perspective view of the tape applicator of the figure 8 in the filling position against a bucket of plaster and connected to a manual filling pump.

[0026] An applicator provided with an access port to the interior of the reservoir according to the invention is illustrated in figure 1 .

[0027] The applicator 1 comprises a dispenser 2 for a roll of jointing tape 3 (illustrated in dotted lines) and a reservoir 4 of coating in which the tape is unrolled, in use.

[0028] The applicator also includes a gripping handle 5 for carrying or operational handling during application of the tape.

[0029] Alternatively or in combination, the applicator may include a gripping strap (S; see figure 8 ) allowing the applicator to be grasped from below.

[0030] As illustrated in figure 2 , the tank 4 has, with reference to the position of use, an entry slot 6 of the strip formed between a free end 7a of a rear wall 7 of the tank and a first free end 8a of a lower wall 8 of the tank.

[0031] The tank 4 also comprises an outlet slot 9 for the strip formed between a free end 10a of a front wall 10 of the tank and a second free end 8b of the lower wall 8 of the tank.

[0032] The tank further comprises two side walls 11 and 12, one of which constitutes a removable side cover 11 allowing access to the interior of the tank 4.

[0033] An application head 13 according to the invention is fixed to the front wall 10 of the reservoir 4.

[0034] According to the invention, the lower wall 8 comprises an orifice 14 provided with a removable plug 15 for access to the interior of the tank. The orifice 13 is directed towards the upper wall 16 of the tank, that is to say it is directed upwards, with reference to the position of use illustrated in figures 1 et 2 . In other words, the orifice has an axis of symmetry XX perpendicular to the lower wall 8.

[0035] Thus, the orifice is opposite the strip when the latter is in the position of use and it extends into the tank between the inlet slot 6 and the outlet slot 9.

[0036] Thus, during the filling process according to the invention, the coating enters perpendicular to the strip and pushes it by gravity towards the upper wall, as will be explained in relation to the figures 5 à 7 .

[0037] Due to this arrangement, the filling of the reservoir is done “upside down”, that is to say that the applicator is turned over so that the lower wall 8 is at the top and the upper wall 16 is at the bottom.

[0038] It is in this position that the applicator 1 is illustrated in figure 3 , before any filling. Thus, the orifice 14 is sealed by the plug 15.

[0039] As illustrated in figure 4 , the cap is removed to allow upside-down filling.

[0040] In a very simple embodiment, the plug can be made of elastomer and forcefully penetrate the orifice to ensure that it is closed. The disadvantage is that the plug must not be too long so as not to protrude too far into the tank and risk tearing the strip when there is almost no more coating.

[0041] Preferably, the orifice 14 is extended, towards the outside of the tank, by a peripheral crown 14a of determined height Hc. This crown allows the gripping of a plug which remains outside the tank.

[0042] Advantageously, the orifice 14 is circular and extended by a cylindrical crown 14a, which allows the use of a screw cap.

[0043] Preferably, the screw cap used is a so-called “quarter turn” cap.

[0044] Thus, the cylindrical crown 14a comprises two fins 14b arranged centrifugally and diametrically opposite each other.

[0045] In a complementary manner, the cap comprises a crown of complementary shape, comprising two legs arranged centripetally and diametrically opposite one another, the legs being intended to be inserted by force between the fins and the lower wall when the cap is closed and to pass between the fins when the cap is pivoted a quarter turn to clear the orifice.

[0046] As illustrated in figure 5 , the lower wall 8 of the tank is advantageously concave, seen from the outside, relative to a base plane P passing through the first 8a and the second 8b free end of the lower wall. These free ends 8a and 8b being straight line segments, the plane P is unique.

[0047] The lower wall 8 has a hollow of maximum height Hm, taken between the base plane P and a lowest point of the lower wall 8, greater than or equal to a height Ht of the orifice provided with the cap. In other words, the height Ht represents the assembly of the orifice (including the crown where applicable) plus the cap, in the application position, that is to say when the cap is locked above the orifice.

[0048] According to the invention, the orifice is arranged in the hollow such that the plug does not protrude from the base plane P.

[0049] In this way, when the plug is locked onto the orifice, the plug remains below the base plane or is flush with the base plane without exceeding it. Thanks to these characteristics of the hollow of the lower wall 8, it is ensured that the applicator can be placed stably on the free ends 8a and 8b, even with the orifice provided with the plug according to the invention. This also makes it possible to avoid any scraping of the plug against the plasterboard during application of the strip.

[0050] THE figures 5 à 7 illustrate the filling method according to the invention, enabled by the structure of the applicator and the arrangement of the orifice 14.

[0051] This filling is illustrated here with the feed pipe 21 of a coating pump 20 (illustrated in figure 9 ).

[0052] To fill the applicator according to the invention for the first time, a free end B1 of the strip B is first inserted into the reservoir through the inlet slot 6 and the free end B1 of the strip B is removed from the reservoir through the outlet slot 9. The strip then extends freely in the reservoir.

[0053] To carry out this operation, you must open the cover 11 to access the inside of the tank.

[0054] According to an advantageous embodiment, the side wall 11 forming the removable side cover is pivotally mounted by a hinge 11a on the upper wall 16, and comprises reversible fixing means 11b on the lower wall to allow reversible sealed closing of the cover.

[0055] This allows easy access to the inside of the tank, and avoids getting filler in the hinge by scraping the filler knife against the bottom wall if the user decides to fill the tank the traditional way.

[0056] The applicator is then turned over to put it in the upside-down position, so that the cap is in the upper position. It can then be opened and a supply pipe 21 of a pump 20 connected to a reservoir 30 of coating 31 can be inserted into the orifice 14.

[0057] The free end B1 of the strip B is held outside the tank and the pump is operated so that coating 31 enters the tank in the direction of arrow F1. In the tank, the coating 31 pushed by the pump tends to fall towards the bottom, that is to say towards the upper wall 16. On its way, as illustrated in figure 6 , the coating 31 meets the strip and pushes it in the direction of the arrows F2 towards the upper wall 16, the rear wall 7 and the front wall 10 until the tank is filled ( figure 7 ).

[0058] Since the tape roll is free to rotate, the tape automatically extends into the reservoir, without the user having to position it.

[0059] Furthermore, unexpectedly, this upside-down applicator position and this filling method avoids any twisting of the strip, which is perfectly applied against the walls of the tank.

[0060] Once the latter is filled, the feed pipe 21 of the pump is removed from the orifice 14 and the cap is closed to obtain a full jointing tape applicator ready for use.

[0061] This filling method is particularly useful during a tape application operation, when the tank needs to be refilled with coating, the tank being almost empty, but having already been used.

[0062] In this case, the strip already extends freely in the tank, with one free end of the strip exiting the tank through the exit slot.

[0063] The applicator is then turned over to put it in the upside-down position, and the cap 15 of the orifice 14 carried by the lower wall 8 of the reservoir 4 is opened.

[0064] A feed pipe 21 of a pump connected to a coating reservoir is then inserted into the orifice 14, then the free end B1 of the strip is held outside the reservoir and the pump is operated so that coating enters the reservoir.

[0065] In a non-illustrated embodiment, the second free end 8b of the lower wall or the application head or the front wall comprises a means for temporarily holding the strip, to prevent the strip from moving back during filling. For example, means for adjusting the height of the strip may be used to temporarily block the strip.

[0066] As previously described, the coating enters the tank perpendicular to the belt and pushes it by gravity towards the top wall, the back wall and the front wall until the tank is filled.

[0067] The feed pipe 21 of the pump is then removed from the orifice 14 and the cap 15 is closed to obtain a full jointing tape applicator, ready for use again.

[0068] Advantageously, a flexible connecting link 15a is fixed between the cap 15 and the lower wall 8 of the tank 4, which prevents the cap from being lost.

[0069] This eliminates the need to open the hood and manually place the strip back into a reservoir covered with coating. This makes refilling very clean and quick. A pump, syringe, or funnel can be used to manually apply the coating.

[0070] In order to allow upside-down filling, the applicator according to the invention comprises two fixing hooks 17 intended to allow, when filling the reservoir with coating, the fixing of the applicator against the edge of a bucket of coating (see figure 9 ), so that the cap and the bottom wall of the tank are facing upwards.

[0071] The hooks 17 are carried by at least one of the side walls 11 or 12, or by an additional plate fixed to one or other of the side walls 11 or 12.

[0072] On the figure 8 , the applicator 1 comprises such an additional plate 40 fixed to the wall 12, this plate 40 carrying the dispenser 2 of the roll of tape.

[0073] The additional plate makes it possible to provide a right-handed or left-handed applicator, depending on the side wall 11 or 12 on which it is fixed. By fixing it to the wall 11, the position of the dispenser 2 is simply reversed, and a left-handed applicator is obtained, as explained below.

[0074] According to the invention, the hooks 17 comprise a wing 17a for fixing to the side wall of the tank (or to the additional plate 40).

[0075] The fixing wing 17a is angularly extended by a support wing 17b against an edge 32 of the bucket (see figure 9), when filling the tank with filler.

[0076] According to the invention, the support wing 17b is angularly extended by a blocking wing 17c intended to block the applicator against the wall of the bucket when filling the reservoir with coating, and to prevent the applicator from tipping over during filling and once filled.

[0077] The fixing wing 17a of each hook 17 advantageously comprises a groove 17d for the passage of a gripping strap S of the applicator, this strap being intended to receive the user's hand, in a position such that the user's fingers are in contact with the lower wall 8 during application of the strip.

[0078] In this way, when the hooks are fixed on a supernumerary plate 40, itself fixed to one or other of the side walls 11-12, it is possible to reverse the position of the supernumerary plate and fix it on the other side wall. The fixing of the reel 2 and the hooks 17 is then reversed, so that the user can use his other hand to implement the applicator according to the invention.

Claims

1. Applicator (1) of jointing tape for joining two sheets of plasterboard, the applicator comprising a dispenser device (2) for dispensing a jointing tape (B) from a roll (3) and a mud chamber (4) through which the tape is unrolled in use, the chamber having, with reference to the use position, a tape inlet slot (6) formed between a free end (7a) of a rear wall (7) of the chamber and a first free end (8a) of a lower wall (8) of the chamber, and a tape outlet slot (9) formed between a free end (10a) of a frontal wall (10) of the chamber and a second free end (8b) of the lower wall (8) of the chamber, the chamber also comprising an upper wall (16) and two side walls (11-12), one (11) of which constitutes a removable side cover for accessing the inside of the chamber, wherein the lower wall (8) comprises an orifice (14) provided with a removable stopper (15) for accessing the interior of the chamber, the orifice being directed towards the upper wall of the chamber, characterized in that at least one (12) of the side walls (11-12) has two fixing hooks (17) that are intended, while the chamber is being filled with mud, to allow the applicator to be fixed against an edge (32) of a bucket (30) of mud (31), such that the stopper and the lower wall of the chamber are directed upwards.

2. Applicator (1) according to Claim 1, wherein the lower wall (8) of the chamber is concave, as seen from the outside, with respect to a base plane (P) passing through the first (8a) and the second (8b) free end of the lower wall, and has a recess with a maximum height (Hm) greater than or equal to a height (Ht) of the orifice (14) provided with the stopper (15), the orifice being arranged in the recess such that the stopper does not protrude beyond the base plane.

3. Applicator (1) according to Claim 1, wherein the hooks (17) comprise a fixing leg (17a) for fixing to the side wall of the chamber, the fixing leg being extended angularly by a bearing leg (17b) for bearing against the bucket edge while the chamber is being filled with mud, the bearing leg being extended angularly by an immobilizing leg (17c) intended to immobilize the applicator against a wall of the bucket while the chamber is being filled with mud.

4. Applicator (1) according to Claim 3, wherein the fixing leg (17a) of each hook has a groove (17d) for a carry strap (S) of the applicator to pass through.

5. Applicator (1) according to any one of Claims 1 to 4, wherein the side wall forming the removable side cover is mounted in a pivotable manner on the upper wall, and comprises means (11b) for reversibly fixing to the lower wall to allow leaktight reversible closure of the cover.

6. Applicator (1) according to any one of Claims 1 to 5, wherein the orifice is extended by a peripheral ring (14a) of given height.

7. Applicator (1) according to Claim 6, wherein the orifice is circular and extended by a cylindrical ring.

8. Applicator (1) according to Claim 7, wherein the cylindrical ring (14a) has two fins (14b) arranged centrifugally and diametrically opposite one another, the stopper having a ring of complementary shape, comprising two tabs arranged centripetally and diametrically opposite one another, the tabs being intended to be force-fitted between the fins and the lower wall when the stopper is closed and to pass between the fins when the stopper is pivoted through a quarter turn to open up the orifice.

9. Applicator (1) according to any one of Claims 1 to 8, wherein a flexible connecting line (15a) is fixed between the stopper and the lower wall of the chamber.

10. Method for filling an empty applicator of jointing tape using a mud pump, characterized in that it comprises the following steps: a) providing an applicator of jointing tape according to any one of Claims 1 to 9 and a mud bucket, b) inserting a free end (B1) of the tape (B) into the chamber (4) through the inlet slot (6) and withdrawing the free end of the tape from the chamber through the outlet slot (9), the tape extending freely through the chamber; c) fixing the applicator against an edge of the bucket of mud using the two fixing hooks (17), such that the stopper and the lower wall of the chamber are directed upwards, and opening the stopper (15) of the orifice (14) borne by the lower wall (8) of the chamber (4); d) inserting a supply hose (21) of a pump connected to a bucket of mud into said orifice; e) keeping the free end of the tape out of the chamber and actuating the pump in order that mud enters the chamber, pushing the tape back towards the upper wall (16), the rear wall (7) and the frontal wall (10) until the chamber has been filled; f) removing the supply hose of the pump from the orifice and closing the stopper in order to obtain a full applicator of jointing tape that is ready to use.

11. Method for adding mud to an applicator of jointing tape using a mud pump, characterized in that it comprises the following steps: a) providing a bucket of mud and an applicator of jointing tape according to any one of Claims 1 to 9, wherein the tape (B) already extends freely through the chamber (4), a free end (B1) of the tape emerging from the chamber through the outlet slot (9), b) fixing the applicator against an edge of the bucket of mud using the two fixing hooks (17), such that the stopper and the lower wall of the chamber are directed upwards, and opening the stopper (15) of the orifice (14) borne by the lower wall (8) of the chamber (4); c) inserting a supply hose (21) of a pump connected to a bucket of mud into said orifice; d) keeping the free end of the tape out of the chamber and actuating the pump in order that mud enters the chamber, pushing the tape back towards the upper wall (16), the rear wall (7) and the frontal wall (10) until the chamber has been filled; e) removing the supply hose of the pump from the orifice and closing the stopper in order to obtain a full applicator of jointing tape that is ready to use.