FR2608069A1 - Improved compressed-air gun - Google Patents

Abstract

This gun, intended for putting down a liquid over a work surface, of the type comprising a spray head which includes a nozzle, connected to a shutoff needle valve driven by an operating trigger, and means for controlling the air pressure and the flow rate of product, a handle which includes an air connector at its base, a container for the product operating by gravity or, more generally, by suction and including a pin-type or screwthread-type closure device, is characterised in that the spray head 2 includes one or two pins 8 enabling the product nozzle 7 to be removed and refitted and the said spray head 2 to be attached, an operating trigger 30 having means for controlling the flow rate of product and for locking the needle valve 5, a chamber 50 containing respectively the spring of the needle valve 5 and the air control valve 42, a self-locking lever-type general valve 25, a suction-operating container 62 which includes an extendable plug seal operated by means of a quarter-turn closure device, a gravity-operating container attached above and along the axis of the handle 69, the latter including a lock mechanism intended for attaching the air connector 52.

Description

 The present invention relates to an apparatus usable for spraying paint or similar surface coating material. musicularly the invention relates to a device of a conventional type having undergone significant improvements, in order to make its use easier.

 More specifically, the invention relates to all the details constituting the apparatuses of the conventional type, having undergone only a few improvements for many years.

The present invention aims to build a more compact, lighter, more easily removable; Built with newer materials such as new plastics, and which allows the application of paint or other surface coating materials, producing a variety of models which cannot be achieved with the conventional arrangements of conventional guns currently in use. In particular, one aspect of the invention makes it possible to place the so-called gravitation tank in the vertical wrist of the operator, significantly improving the hand.

 The application of paints or other surface coating fluids, such as lacquers, worms and spray paints has long been a significant element in the commercial possibilities of high volume painting and finishing. A source of compressed air having the necessary characteristics and the complexity of the guns to provide acceptable results has generally limited the spraying operations of paint and finishing material to commercial applications. In recent years, however, many factors have contributed to a tour use. more widely spread of gun equipment applicatiors outside industrial paint and finish applications. A first factor in this generalized wisdom of guns is the relatively recent presence of air compressors having suitable performance characteristics at very reduced prices. . In addition, pistols having the characteristics suitable for uses other than continuous industrial uses are available from different sources for a fraction of the price of conventional industrial units.

 To the knowledge of the applicant, the various industries supplying the current markets for conventional pistols operating with compressed air and using handcrafted equipment have practically not innovated on this type of device for twenty years; especially in that; concerns the following elements: the closure of the reservoir produces the mounting of the diffuser cap, the nozzle, the shutter needle, the air valve requiring a separate compartment, the various flow and side jet adjustments, the gravitation reservoir generally fixed above the diffuser, make the device difficult to handle by the imbalance effect of the handle supporting the device. The most striking arrangement in recent years is the provision of a compressed air pre-adjustment valve incorporated in the handle and called "general valve" acting like an air regulator. This so-called general valve is in the form of a knurled button coupled to a needle rod, although useful this device is of an inconvenient adjustment.

 As a result, an object of the invention is to provide another type of wanne, in the form of a second trigger, instantaneously adjustable with a finger, and without interrupting the spraying making the device much more efficient, in particular when it s '' is difficult to access work, for example door entrances in bodywork or other decorative aspect, some work requiring, a hand to hold a cardboard cover useful to delimit very quickly the areas to lose, or to hold the 'air supply; It has been shown that being able to adjust and hold the machine in one go significantly improves performance and maneuverability.

 Another object of the invention is to furJx a projector nozzle, of a reduced size therefore light, removable and reassemblable without using a tool; the fixing lug ypourvoit advantageously as well as the mobile fixing of the fused hat, greatly facilitating the sumultannées operations of horizontal or vertical pulveri station, without unscrewing, as well as for removing and installing the diffusing cap, either to quickly check its cleanliness.

 Another innovation of the invention is to allow the use of more current materials such as new plastics, to produce the gun body, the present invention uses a combination of tightening and loosening of the nozzle, requiring only a very low torsional pull on the said body w gun. Conventional nozzles existing on the market generally require the comfort of a wrench for the operation of removing and installing them; the traction exerted on said pistol body is much greater, hence the need for a more rigid and generally heavier material.

 The main object of the invention is to allow conventional use, that is to say the surface covering with a product sprayed using a source of compressed air, with a topical device, lighter and more manageable.

 The invention allows, by its new technical configuration, the fixing at the rear of said body of the apparatus, of a gravitation tank whose location advantageously eliminates the effect of lateral sway and of imbalance advent common to conventional gravity tanks, which make the dwarf blow badly air at full load ge of the product tank. The present invention allows said gravitation tank to be located immediately above the wrist and in his groin, with a backward tilt making the device more compact and more aesthetic and finally much more manageable, this is the goal.

 Another advantage of the present invention is the development of an assembly arranged in a mime detail of said gun body, composed of the air control valve, and of the closing spring of the shutter needle of the nozzle. The originality of this said assembly, is noted by the axial connecting rod, joining the two main parts, the shutter needle, and its spring; allowing the two valve stems and needle rods to move separately in the same joint, respectively. This compact technique gives, in addition to the aesthetics, less fractuosity allowing easier cleaning. This said assembly my by a control trigger comprises a detail which allows its removal and its resting instantaneously, thanks to a technique which will be described in more detail later. This arrangement allows the said trigger to position itself in removal of the needle, or in the operating position, finally the said trigger incorporates the flow adjustment, making the latter advantageously accessible both manually and visually, whether the operator is left-handed or right-handed.

 According to yet another technical characteristic, the so-called general valve and the regulating valve for the lateral jets are arranged axially in the room, this arrangement facilitates the respective settings in a range of approximately 1600 numbered from 0 to 6, zero equal to the total closure and six mamum air channels. The numbering constitutes a visual reference for the operator, avoiding him the test jets necessary for the adjustment of the other types of valves.

 According to yet another object improving the maneuverability of the device, the air supply connection being housed in a detail of the butt, so as to allow only a flexible tube to appear, freeing as much as possible the base of said butt, which includes a lock for connecting or releasing said air supply fitting. The object of the invention is to this end to significantly improve the rotation shot of the wrist supporting the device in front of the work surface.

 According to yet another important technical achievement, the product reservoir, known as suction closed by a closure known as an "extendable plug", composed of a rigid support, mounted pivoting to 0O in the radial direction on the gun body. A second part having the general shape of a round box, of flexible material and coming to fit interchangeably, to said support, thanks to circular details, respectively internal and external, forming a case intended to receive the closing mechanism that we will describe in more detail later.

 Said expandable plug can also be used for any other closure of a container or instrument, both in industry and in special cases.

 The advantage of this closing technique is characterized by the fact that it does not require any anchoring point, hook, lug or no screws on the inlet edges of the container which cause annoying roughness for the user, such as most of the conventional closures.

 The present reservoir has at its entry only a smooth circular boss.

 We understand that thanks to this arrangement, the cleaning operation is much easier, especially for devices requiring cleanliness at all times and in addition the more precise and more fixable closing action.

 In general, the main aims are achieved, namely, the compact appearance of the device, its aesthetics, its maneuverability, the easy cleaning operation, the removal and installation of the diffuser cap, the nozzle and its needle. shutter, parallel performance improvement.

 All these new techniques have also been studied to advantageously arrange the said spray gun for applying hot paint, Erevet number of the international application: P.C.T./FR 80/00184, in the name of the applicant.

 This device, although it is heating belonged to a range of conventional devices, operating from a source of compressed air, this process is more appreciated by professionals in automobile bodywork, decoration etc.

whose work requires finishes as perfect as possible.

 It is to be noted that the attachment pin must be installed differently, in the diffuser cap, for example it is possible to provide two pins (instead of one) placed one opposite the other in the same axis. , by mode of fixing, -n flexible or rigid, in parallel the nozzle can also undergo modifications, according to the technical needs, As well as the extensible plug can be closed using a quarter-turn lever.

These other characteristics and advantages of the invention will be better understood on reading the following description of an embodiment and with reference to the appended drawings in which
Figure 1 shows an axial section of the gun according to the invention with its components assembled functionally, showing in phantom in the upper rear part, the gravity tank, in the front lower part is located the suction tank and its cap extendable, finally the connection of the pressurized air supply.

 FIG. 2 represents the diffuser cap and its nozzle in 3/4 section indicating the exact position of the fixing lug and its passage in a detail arranged in the circular support of the nozzle.

 FIG. 3 represents a 3/4 sectional view of the various parts making up the fixing hub of the diffuser and product nozzle assembly.

 Figure 4 shows a demonstration in front view of the different functions of said fixing lug.

 5 shows a cross section substantially along the lines B-B of Figure 2, showing the positioning of the lug which preferably is located at an angle of 90 degrees relative to the inlet pipes of the side jets.

 Figure 6 is a cross section substantially along line A-A and showing the components of the air control system and the various pipes.

 FIG. 7 represents an exploded view of the various parts making up the whole of the locking system of the general valve.

 FIG. B represents a view in axial section of the various parts comprising the mechanisms linked to the control trigger, shutter needle and air valve.

 the figure represents a demonstration of the locking system of the shutter needle, in F locking, in G unlocking releasing the needle.

 Figure 10 shows a demonstration of the operation of the air valve and the shutter paint.

 figure It represents a -r th. axial section, showing the profile of the two main parts closing the housing of the closure mechanism.

FIG. 12 shows, for information only, the numerous mechanical possibilities of the closing transmission
FIG. 13 shows in section the details making up the housing of the bou coron in the open position of the product reservoir.

 Figure 14 shows in section the moving details of the cap when closing the tank.

 Figure 1; shows a side view of the gun equipped with a gravity cup and its tube for bringing the product to the diffuser. We remove the depopulated suction tank.

 A gun according to the invention, generally designated by the board 1/4, is designed to operate with compressed air. As can be seen in FIG. 1, the pistol has a body generally designated by the reference 1 comprising in its mass a stock 69 and in the seating plane for fixing the 1/4 and 4/4 plate gravity reservoir. Said body 1 is preferably made of molded plastic comprising parts included in its mass, mainly the combined pipe 4 also acts as a support for various parts making the projection part in FIGS. 2 and 3. hermetic seat to the Teflon joint "18 of the diffuser cap 2, the said large hub 3 has a certain number of holes 16 forming pipes leading to the lateral jets of the diffuser cap 2.

the said small hub 6 screwed onto the support tube 4 serves to hold the large hub 2, and preferably has an O-ring 14 coming as a sealed amplifier on the internal and circular face 13 (of the diffuser cap 2) separating the two pipes 16 ( lateral jets) and 15 (extraction jet) Figures 3 and 4.The support tube 4 comprises in the radical and annular direction of the outlet one by conical 10 to about 45 constituting the sealed seat of the nozzle 7 when it is screwed in to the wing of said diffuser cap 2 comprising a lug 2 in figure 2 which engages at first pressure in the passage o in figures 2 and 4, in the position of fitting or removing the nozzle 7, a second pressure towards the rear places said lug 8 in position E facing the circular locking passage 11, a slight pressure in rotation on the diffuser cap 2, engages said lug 8 in said circular passage 11, preferably the positioning of the diffuser cap 2 s '' performs by quarter turn 4 PL 2/4, position B vertical scan of the work surface, in position C horizontal scan. me annular plan 12 figure 2 in which is housed without lateral play the external wall of the nozzle 7. This description shows the diffuser and operating position figure 1 - Pi 1 / 4.The adjustment of the lateral jets is carried out by l the index of valve 19, by placing said index selectively on a number corresponding to a programmed result, by the more or less pronounced shutter effect of the air inlet of the pipe 16 FIG. 6, supplying in air pressure, the lateral jets, pressure equal to or less than the extraction jet supplied by the pipe 15 in FIG. 6, the said extraction jet not requiring adjustment.

the valve 19 held by means of a thread in the support 70 (embedded in the body 1), and the other end of the said support 70 is to be closed by the valve 23 (also held by a pitch of screw) and comprising an air passage 24 figure 7 backed by a 2nd passage corespondant to the intermediate tube 20 connecting the control valve 4 figure 8 whose action releases or cuts the air pressure from a source of The general valve 23, the rotary action of which more or less blocks the air supply from the intermediate tube 20, the purpose of this effect being to reduce the initial pressure in the pipes upstream of the said general valve 23 which acts as an air regulator. This result is obtained by acting on the lever 25 comprising at its end a supporting detail 29 allowing the action with the index finger of the hand supporting the gun. Said lever 25 comprises a blocking in position for an air flow chosen, the blocking is obtained by the bearing effect of the pad 2 on the body 1 trace to the action of the spring 27 retransmitted by the aie 2c to the said pad 25, the pressure of the spring 27 is contained on the one hand In a detail of the valve 23 and in a second detail of the lever 25, this device allows quick and precise adjustments.

The trigger 30 brings together several devices, one of which are 35 fixed in the body 1, a part 31 of the trigger 30 has bosses 36 and 72 allowing two vertical positions and the total removal of the trigger 30 a steel blade 34 of which a part narrower acts as a spring for snap-fitting of the trigger 30 on the gate 35. Said blade 34 in flat steel has in the center e its widest part one. hole 3 of a diameter allowing the release as of the shoulder pad 3-t in figure 11, said blade 34 also includes another rectangular hole in the hole 38 in figure 9.This hole in this respective parts is intended to successively allow the removal of the needle 5 by the action a simple downward pressure placing the axis 3 above the boss 36 and the drilling 38 face aï pad 39 action figure in S, secondly the nozzle 7 installed, the needle 5 is released axially towards the - :: ant under the acticr of the spring 45 secured to the shutter needle 5 by means of the push rod 4C FIG. 8. The reassembly of the needle takes place in the other direction , by replacing the needle 5 in the product line 4 and err screwing the nozzle 4 back fully, constraining the retraction of the needle 5 and its shoulder pad 39 coming to be placed in a detail of the valve stem 41 against the action of the spring 45 by means of the push rod 40 sliding in a bore central and axial formed in the valve stem 41, the said stem is sealed by the seal 44, the water 5 in the closed position, there remains to exert a vertical pressure upwards on the trigger 30 for replace the boss 36 above the aisle 35, the needle 5 is locked as shown in the drawing
F figure
The respective operation of the needle 5 and of the valve 42 is carried out in two stages, the figure It is a demonstration, a first pressure on the trigger 30 presses on the rod 41 of the valve 42 in a movement of recoil against the action of the spring 43 against the intermediate pad 47, the opening stroke of the valve 42 initially limited in a range HI

Figure 10 said valve 42 detached from its annular seat 45 allows the passage of air pressure in the conduit 20, the sealing of said valve stem is ensured by the seal 73 and its screwed support 46 closing the chamber 50 a second, stronger pressure exerted on the squeegee 30 brings the blade 34 and the locking stud 39 into contact, successively assisting backward (in a range between J and K) the needle 5 (unclogging the nozzle 7), the push rod 40, the stud 47 against the action of the spring 48 against the bottom of the chamber 50. the product outlet from the nozzle 7 being unclogged the adjustment of its flow rate is effected by limiting the stroke of the trigger 30 by l 'intermediate of the rod 33 coupled to a thumbwheel 32. The stick 69 comprises a room containing a connection plug 51 held by a screw 74, a removable connector 52 coupled to the compressed air tube and held by a latch 53, part of which housed and maintained in a lower detail e the stock 69 with the aid of a wing 75 the operation of the lock 53 is ensured by a spring 76 placed axially at the lug of the connection lock 53 in figure 1/4.

 The product reservoir said to be in gravitation 66 is fixed to the vertical of the handle 69 with the aid of a screw 77 held in a detail of the seat plane 6 of the body 1 FIG. 1/4. The reservoir 66 peddles at its base in an offset plane a product outlet 7g connected to an intermediate conduit 67 the other end is also connected to another inlet 21 (using a screw 70) accessing the conduit t of the diffuser. Reservoir 66 has at its upper part having a support hook and a closure cover.

 ile said suction tank 62 whose closure acts laterally on the interior walls 86 is hermetically locked in the annular detail 64 FIG. 14 of the housing 55 associated with its support 54 by details 63 with annular slotting interlocking mobile and hermetic, both parts 55 and 54 forming a room contain the mechanism n in the form of a segment 56 supported on the internal walls of the housing 5, the said segment 56 whose ends have a conical cut forming slides 61 associated with a mechanism 'extentlon 59 in the general form of a pair of shears assembled by ase ase 6 and whose arms 86 are placed so that by acting a quarter turn on the cam 58 (integral with the suction tube 57 fixed to the body causes the separation of the arms 86 associated with the jaws 59 for opening the segment 56 transmits its extension effect to the internal wall 87 of the housing 55 made of flexible, retractable and non-adherent material. e to this arrangement this method of closing is advantageously suitable for this type of device in particular, and for all others in general, requiring a similar closure.

 Said plug Or extendable cover has an air inlet 65 taken; quée in the axis 60 interior mechanism.

 Of course, various modifications can be made by those skilled in the art to the devices or methods which have just been described only by way of nonlimiting examples without departing from the scope of the invention.

Claims (11)

R E V E N D I C A T I O N  1 - Gun intended to deposit a liquid on a work surface, of the type comprising a diffusion head comprising a nozzle, associated with a shutter needle a by a control trigger, and means for adjusting air pressure and flow of product, a handle comprising an air connection at its base, a reservoir for gravity or more generally suction product comprising a lug or screw weight closure, characterized in that the diffuser cap 2 comprises one or two lugs 8 allowing the removal and the refitting of the product nozzle 7 and the fixing of said diffusing cap 2, a control trigger 30 having means for adjusting the flow of product and locking the needle 5, a chamber containing respectively the spring 48 of the needle and the air control valve, a general self-locking lever valve 25, a suction tank comprising an extendable cap controlled by a quarter-turn closure, a gravity tank fixed to the d essus et car, because of the handle 69, which has a lock intended for fixing the air connector 52.  2 - Pistol according to claim 1 characterized in that the dIofuseur 2 cap is rotatably mounted by means of the lug 8 moving in the annular passage 11 formed by a detail of the nozzle 7 and the small hub 6.  3 - Pistol according to claim 1 characterized in that the said pin E positioned in the passage 9 of the nozzle 7 allows the installation or removal of the nozzle nozzle T (FIG. 4).  - 'istolet according to claim 1 characterized in that the general valve ^, is actuated by a lever comprise a self-locking system in position, Figure 7.  5 - Gun according to one of the preceding claims, characterized in that the general valve 23 and the valve for adjusting the lateral jets of the diffuser cap 2 are mounted axially in the same room and separately adjustable.  6 - Gun according to claim 1 characterized in that the control strip 30 comprises a control wheel for adjusting the product flow rate and means for locking the needle 5.  7 - Gun according to claim 1 characterized in that the rod 41 of the control valve 42 has "r axial bore over its entire length allowing the sliding passage of the push rod 40 the two rods can move separately or together in one same confused.  8 - Pistol according to claim 1 characterized in that the liquid reservoir has an inlet with smooth walls closed by an extendable plug whose closure is effected by rotating the reservoir 62 a quarter of a turn.  9 - Pistol according to one of the preceding claims characterized in that the two parts 55 and 51 are assembled by means 63 forming a housing intended to receive the closing mechanism.  10 - Pistol according to one of the preceding claims, characterized in that the mechanism of the extendable central plug plug (FIG. 11) comprises a cam 5 integral with the product tube 57 serving to spread the arms 86 of the shear-shaped mechanism comprising jaws 5 housed sliding in the conical slides 61 of the transmitter segment 56 which, deviating, presses the circular detail 64 on the annular book of the reservoir 62 (FIGS. 12 and 13).  11 - Gun according to claim 1 characterized in that the handle 69 has at its base a lock kept movable in a detail of one air connection inlet.  12 - Pistol according to claim 1 characterized in that the plane 6 is provided for receiving the attachment to the gravity tank connecting to the diffuser 2 by the supply tube 67.