Device for dispensing fluid and/or semi-fluid products

Abstract: The device for dispensing fluid and/or semi-fluid products, for example silicones comprises a tubular body (1) in which a cartridge (2) which contains a product (3) to be dispensed is accommodated. The body is provided, at the front, with a dispensing nozzle (10) which defines an annular chamber (13) around a product output spout (5). The body is provided, at the rear, with telescopic pusher means (17) which act on the cartridge (2). A cutoff valve (20), to be connected to a compressed air supply hose (45), is connected to the annular chamber (13) and to the pusher means (17) and is associated with the tubular body (1).

Description: The present invention relates to a device for dispensing and/or spraying fluid and/or semi-fluid products. In particular, the device is suitable to dispense single-component products based on silicone or polyurethane, and products for forming seals, etc., packaged in rigid or soft cartridges (bags). Devices substantially constituted by a tubular containment body provided, at the front, with a dispensing nozzle are currently used to dispense silicones or the like packaged in cartridges with an axial front dispensing spout and a movable rear bottom. The body is supplied, at the rear, with compressed air which acts directly on the bottom of the cartridge or on a double pusher piston. The supply of air is controlled by a cutoff valve which is associated with the body and which is provided with an air flow-rate regulator. The width of the delivered flow of the products is adjusted manually by varying, by means of a ring device, the mutual position of the product output spout and the dispensing nozzle. Also known from DE-U-9,011,965 is a device for dispensing fluid and/or semi-fluid products as defined in the preamble of claim 1. These known dispensing devices, however, are affected by various problems; in particular, in the device in which the compressed air acts directly on the bottom of the cartridge, air leaks easily occur between the bottom and the walls within which it slides. This causes the forming of bubbles inside the product and thus, as it is expelled, the forming of discontinuities in the dispensed bead. This is a considerable problem if the product being dispensed provides for example the weather strip of a motor vehicle window. In the case of devices with a double pusher piston, a considerable problem is due to the excessive longitudinal dimensions of the containment body, which are indeed due to the piston, which make the unit difficult to handle. Other problems are due to the fact that the air is adjusted in terms of its flow-rate and not of its pressure. The aim of the present invention is to provide a device for dispensing fluid and/or semi-fluid products which eliminates the problems described above in known types. A consequent primary object is to provide a device which is capable both of dispensing beads of product having an adjustable width and shape and of spraying nebulized product with an adjustable spraying width. Another important object is to provide a device which can dispense both products packaged in a rigid cartridge and products packaged in a bag. Another important object is to provide a device which is practical and easy to handle. Not least object is to provide a device which can be manufactured with conventional equipment and production facilities. This aim, these objects and others which will become apparent hereinafter are achieved by a device for dispensing fluid and/or semi-fluid products, as defined in the appended claims. Further characteristics and advantages of the invention will become apparent from the detailed description of an embodiment thereof, illustrated only by way of non-limitative example in the accompanying drawings, wherein: figure 1 is a perspective view of the dispensing device according to the invention; figure 2 is a longitudinal sectional view of the device of figure 1; figure 3 is an enlarged longitudinal sectional detail view of the part related to the cutoff valve; figure 4 is a perspective view of the body of the valve of figure 3, with two associated pressure regulators; figure 5 is a sectional view, taken along a horizontal median plane, of the body of figure 4; figure 6 is a perspective view of the body of the valve of figure 4 on its own; figure 7 is a sectional view, taken along a vertical median plane, of the body of figure 6; figure 8 is a sectional view, taken along a horizontal median plane, of the body of figure 6; figure 9 is an enlarged sectional view of a detail of the bottom of the dispensing device of figure 1. With reference to the above figures, a device for dispensing fluid and/or semi-fluid products according to the invention comprises a tubular body 1 which has a circular cross-section and in which, for example, a cartridge 2 of a kind normally commercially available which contains a product 3 to be dispensed, for example a silicon-based product, is suitable to be inserted. Said cartridge 2 is provided, at the front, with a threaded axial tang 4 on which a product output spout 5 is screwed, and is provided, at the rear, with a bottom 6 which can slide internally on its walls. Said tubular body 1 is provided, on its front end, with an external thread 7 on which a first ring 8 is screwed; said ring defines an axial cylindrical seat for the insertion of the base 9 of a dispensing nozzle 10. Said base 9 is provided with a circumferential ridge 11 which abuts on said first ring 8 and which is locked by a second threaded ring 12 which is screwed on an external thread of the first ring. Said dispensing nozzle 10 defines, around the spout 5, an annular chamber 13 whose outlet is located at the end for the delivery of the product 3. Said tubular body 1 is provided, on its rear end, with an external thread 14 on which a third ring 15 is screwed; said third ring retains a bottom 16 from which a telescoping piston, composed of four coaxial elements and generally designated by the reference numeral 17, extends inside said body 1. In a median region, said body 1 is provided with a cutoff valve, generally designated by the reference numeral 20, which is fixed to said body in a downward position by means of a strap 19 which surrounds it; said cutoff valve is provided with a handgrip 21 in a downward position. Said valve 20 comprises a body 22 which is constituted by a metallic block which extends longitudinally with respect to the tubular body 1; a cylindrical seat 23 is defined in said block in a downward position and in a longitudinal arrangement; said cylindrical seat is open at the front and is provided with a terminal thread in which a cylindrical element 24 is inserted and screwed; said element 24 has an axial hole in which an equally cylindrical rod 25 can slide. Said element 24 defines, together with the wall of the seat 23 and with the rod 25, two annular chambers, respectively 26 and 27, which are connected by a hole 28 which extends radially. The annular chamber 27 is conveniently open at the rear. Sealing rings, respectively 29 and 30, are arranged between the mutually contacting surfaces of the element 24 and of the seat 23 and between the mutually contacting surfaces of the rod 25 and of the element 24. The bottom of the seat 23 is connected, by means of an axial hole 31, to another cylindrical seat 32 which is coaxial to the preceding one and which is closed, in the rear region of the body 22, by a plug 33 which is screwed onto a threaded region thereof. Said rod 25 passes through both seats 23 and 32 and protrudes from the cylindrical element 24 with an end 34 on which a lever 35 acts; said lever 35 is articulated to the body 22 in an upward position. A chamber 36 (figure 3) is defined, between the element 24 and the bottom of the seat 23, for a first annular shutter 37 which is suitable to open and close the connection of said chamber 36 with the annular chamber 27. A sealing ring 38 is located at the hole 31, is accommodated in a seat defined by two annular ridges, respectively 39 and 40, of the rod 25, and constitutes a second shutter. A spring 41 is arranged in the chamber 36 between the annular ridge 40 and the plug 33, and is suitable to contrast the translatory movements of the rod 25 imparted by the lever 35. Said spring 41 rests, with its base, on a disk-like element 42 which encloses a sealing ring 43 in an appropriate seat of the plug 33 around the rod 25. A substantially radial hole 44 ends in said chamber 36, and a portion of a hose 45 for supplying compressed air is connected to said hole. By pressing on the lever 35, the rod 25 is moved toward the rear part of the body 22, and the shutter 37 immediately opens the connection between the chamber 36 and the chamber 27. As pressure continues, in contrast with the action of the spring 41, the sealing ring 38 also frees the passage between the chamber 36 and the seat 32. The valve 20 has two pressure regulators, respectively 46 and 47, which are arranged side by side above the rod 25 at right angles thereto; their cylindrical seats 48 and 49 are defined in the body 22 and are connected respectively to the chamber 26, by means of a hole 50, and to the seat 32, by means of a hole 51. Conveniently, the hole 51 is defined at an angle in the body 22 and is closed by plugs 52 and 53. The two pressure regulators 46 and 47 are identical, and therefore only one of them is described hereinafter. In particular, the regulator 46 comprises the seat 48, which is substantially divided into two regions, respectively 54 and 55, by a tapered portion 56. A first piston 57 can slide in the first region 54, into which the hole 50 leads; said piston 57 supports a sealing element 58 in a front position and is pushed at the rear by a spring 59 which is interposed between said piston and a plug 60 which is screwed on a corresponding threaded end region of said first region. An axial wing 61 abuts on the sealing element 58 and extends from a second piston 62 which can slide in the second region 55. Said second piston 62 is conveniently provided with an outer sealing ring 63 which slides on the wall of the second region 55. The wing 61 and the piston 62 are axially crossed by a hole 64. The piston 62 is pushed toward the piston 57 by a spring 65 which is interposed between said piston 62 and a knob 66 which is screwed on an external thread of the body 22 which is coaxial to the region 55. Conveniently, the knob 66 is provided with an axial hole 67 for the passage of air. A hole 68 leads radially outward at the tapered portion 56 and, by means of a connection 69 and a tube 70, is connected to the annular chamber 13. A radial hole 72 ends in the corresponding tapered portion 71 of the seat 49 of the regulator 47 and is connected, by means of a coupling 73, a tube 74 and curved couplings 75, to an axial hole 76 of a cylindrical element 77 which is screwed in an axial seat of the bottom 16. The cylindrical element 77 defines, together with the bottom 16, a chamber 78 into which said hole 76 leads and into which a shutter 79 is arranged; said shutter 79 is made of an elastomer material and has a disk-like shape, with an annular peripheral lip 80 directed toward the inside of the tubular body 1. Said chamber 78 is connected to the rear part of the telescopic piston 18 by means of a hole 81 which is provided on the bottom 16 in an axially offset position. Said bottom 16 is furthermore provided with a diametrical hole 82 which is connected to the outside by means of venting holes 83, with which it is provided in an axially offset peripheral region, and to the inside of the chamber 78 by means of a hole 84 with which it is provided in an axial position. As regards the operation of the above described device, after connecting it to a compressed air hose and after positioning a cartridge 2 inside it (by unscrewing the first ring 8), it is sufficient to act on the lever 35, which by pushing the rod 25 initially opens the shutter 37, sending air into the chamber 13 and thus cleaning the nozzle 10. A further actuation of the lever then opens the passage toward the bottom 16. The air enters the chamber 78 and pushes the shutter 79 so that it closes the axial hole 84. By passing circumferentially between the lip 80 and the walls of the chamber 78, the air passes through the hole 81, actuating the telescopic piston 17. Said piston pushes on the bottom 6 of the cartridge 2, preventing the rearward escape of the product 3 while it is pushed out the output spout 5. When the lever 35 is released at the end of operation, the spring 41 returns the rod 25 to its initial position, closing first the rear air passage and then the front air passage. During this interval, the annular chamber 13 is still subjected to the flow of air, and this cleans the nozzle 10. When the rear air flow stops, the compressed air which is present inside the telescopic piston 18 pushes the shutter 79 so that it closes the hole 76, consequently opening the hole 84. The air is thus vented through the hole 81, through the hole 84, to the hole 82 and thus to the venting hole 83. The effect of the front and rear air sprays on the dispensed product is changed by acting on the pressure regulators 46 and 47. In this manner it is possible to vary the width of the output bead until the product is actually nebulized and dispensed as a spray. The end of the dispenser nozzle 10 can conveniently have another geometrical shape apart from the circular one. The spout 5 can also be replaced with other ones in order to adapt to the specific requirements of use. As regards the pressure regulators, the rotation of the knob 66 pre-loads the spring 65 and the resting pressure of the wing 61 on the sealing element 58. The compressed air enters through the hole 44 and the seat 48, and exits through the hole 68. If the pressure causes a force which is greater than the force exerted by the spring 65, it pushes the second piston 62 backward and exits through the hole 64. In practice, it has thus been observed that the above described dispensing device has achieved the intended aim and objects of the present invention. The presence of the rear telescopic piston makes its dimensions extremely compact and thus makes the entire device much easier to handle than those already commercially available. The presence of two separate pressure regulators allows the optimum adjustment of the air both at the front and at the rear, adapting both the optimum thrust of the telescoping piston and the optimum output spraying action to all operating requirements. The non-simultaneous actuation of the air passages allows to clean the nozzle before the product flows out and after interruption. The presence of the rear quick-venting valve allows to immediately stop the output of the product when the actuation lever is released. The device thus conceived is susceptible to numerous modifications and variations, all of which are within the scope of the inventive concept. All the details may furthermore be replaced with other technically equivalent elements. In practice, the materials employed, so long as they are compatible with the contingent use, as well as the dimensions, may be any according to the requirements. Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the scope of each element identified by way of example by such reference signs.

Claims: Device for dispensing fluid and/or semi-fluid products comprising a tubular body (1) for accommodating a cartridge (2) which contains a product (3) to be dispensed, said tubular body (1) being provided, at the front, with a dispensing nozzle (10) which defines an annular chamber (13) around a product output spout (5), and, at the rear, with a compression chamber (78) which acts on the bottom (6) of said cartridge, said body (1) being associated with a cutoff valve (20) to be connected to a compressed air supply hose (45) which is connected to said annular chamber (13) and to said compression chamber (78), wherein the line (74) which connects said cutoff valve (20) to said compression chamber (78) is provided with a pressure regulator (47) characterized in that it comprises telescopic pusher means (17) which act on the bottom of said cartridge (2), and in that the line (70,) which connects said cutoff valve (20) to said annular chamber (13) is provided with an independent pressure regulator (46,). Device according to claim 1, characterized in that said cutoff valve (20) comprises a body (22) wherein a seat is defined longitudinally for the sliding of a rod (25) which is associated with a pusher lever (35) articulated to the body (22) at one end and with elastic contrast means (41) at the other end, two annular chambers (23,32) being defined in said sliding seat, said chambers (23, 32) being coaxial to said rod (25) and being connected to one another by means of a passage (31) with a reduced cross-section, a first one (23) of said chambers, which is connected to said annular chamber (13) of said dispenser nozzle (10), being also connected to an air supply hose (45), a second chamber (32) being connected to said pusher means (17), said rod (25) being provided with a first shutter (37), for opening and closing the connection to the annular chamber (13) of said dispenser nozzle (10), and with a second shutter (38-40), for opening and closing the passage (31) which interconnects said first chamber (23) and said second chamber (32). Device according to claim 2, characterized in that said shutters (37,38-40) of said cutoff valve (20) are arranged on said rod (25) whereby opening of the air passage (31) toward said annular chamber (13) of said nozzle (10) occurs before the opening of the air passage (31) toward said pusher means (17). Device according to claim 2, characterized in that each one of said pressure regulators (46,47) comprises a cylindrical seat (48,49) which is defined in the same body (22) as said cutoff valve (20) and which is substantially divided into two regions (54,55) by a tapered portion (56), a first piston (57) being slideable in a first one (54) of said two regions, into which a hole (50) for connection to said cutoff valve (20) leads, said first piston (57) being frontally provided with a sealing element (58) and being pushed at the rear by a spring (59) interposed between said first piston (57) and a plug (60) screwed on a corresponding threaded end region of said first region (54), an axial wing (61) abutting on said sealing element (58), said wing (61) extending from a second piston (62) which is slideable in said second region (55), said second piston (62) being provided with an external ring (63) for providing a seal on the internal wall of said second region (55) of said cylindrical seat (48, 49), said wing (61) and said second piston (62) being axially crossed by a hole (64), said second piston (62) being pushed toward the first one (57) by a spring (65) which is interposed between said second piston (62) and a knob (66) which is screwed onto an external thread of the body (22) which is coaxial to said second region (55), an air delivery hole (68) being provided radially at said tapered portion (56).

Inventors: COZZA OSCAR, COZZA, OSCAR
Applicants: ANI OFF MEC SPA, OFFICINE MECCANICHE A.N.I. S.P.A.
Application year: 1992
Main classification: B05C17
IPC codes: B05B7, B05C17