NO820314L - Hand-MIX GUN - Google Patents

Abstract

1. A hand mixing gun for the simultaneous extrusion of two low to highly viscous liquids out of a cartridge device containing two liquids separately, in which cartridge device a discharge piston (2) is displaceable for each liquid, with a receiver for the cartridge device, a mixing tube (4) to which the outlets of the cartridge device can be connected and which has an outlet nozzle (6) for the mixed liquids, two piston rods (3) which can be pushed into the cartridge device from the side opposite to the outlets of the cartridge device to push the discharge pistons (2) forwards and a drive motor (9) to move the piston rods (3), wherein the cartridge receiver is adapted to store two cartridges side by side, characterized in that a change-speed gear (8) is provided, which permits the drive of the two discharge pistons (2) at feed speeds, the ratio of which to one another can be preset in order to produce a desired mixing proportion of the two liquids.

Description

The invention relates to a hand-mixing gun for simultaneous

in pressing two liquids as stated in the introduction of the main claim.

Two-component masses, such as adhesives, sealants, fillers for joints etc. are often used in connection with construction, assembly etc., and must be for this purpose first! are mixed with each other in a more or less exact mixing ratio before they applied to...

As the mixed liquids, which often have a high viscosity, tend to solidify or harden quickly after mixing, it is appropriate to carry out the mixing just before application.

A hand-mixing gun for two-component masses is thus known, where two coaxially situated cylinders, each filled with its own component, form a cartridge, which can be inserted into the mixing gun, which includes a mixing tube for the components . At the other end of the piston there is a handle, which via two piston rods is connected to two pistons, which go into their respective component containers and are pushed forward at the same speed.

• .. I

The special advantage of this gun lies in the fact that the two components are mixed together immediately before application and that, due to the geometry of the containers, it is possible to! adhere to an exact mixing ratio.'i

With the known gun, however, it is unfortunate that a separate, suitable cartridge must be produced for each mixing ratio. Such cartridges are very demanding in production and are also difficult to fill. That is a significant disadvantage, then. the cartridge is only used once.

These disadvantages are partially eliminated by another, known processing gun, where one component, which is in a hose in the cartridge, can be pushed out together with the other component using compressed air, after which mixing takes place in etj mixing tubes using a motor driven agitator.. i.

i However, the known processing gun is not capable of mixing together components, which are filled in beforehand,

in a changeable mixing ratio adapted at all times..

i Based on the position of this technique, . according to the invention, a hand-mixing gun as stated in the introduction of the main claim, which has been further developed in a simple way so that it can dispense ready-mixed pastes without structural changes, which are mixed by two standard cartridges which are filled with different components, where the paste's component ratio is adjustable at all times and thus suitable for different two-component masses.

i This is achieved using the features specified in claim 1.

in i

Since the drive device for the advancing pistons drives these with the same or different advancing speed, in which

the ratio between the advance speeds is adjustable and can be precisely observed, it is sufficient to introduce the cartridges with the two components in the receiving part, connect them to the mixing tube and, in connection, set the drive device corresponding to the desired mixing ratio, so that the two the liquids emerge from the cartridge outlet openings in precisely the correct dosage to the mixing tube, where mixing takes place

■ in place in connection.

In practice, it may be appropriate to drive one of the two piston rods at a constant reference speed and push forward the other piston rod correspondingly faster or slower.

In one embodiment of the invention, it is advantageous that the pasta containers are the same size, so that a significant simplification of production is achieved. As the mixing ratios for two-component pastes are usually between 1:1 and 10:1, correspondingly different feed speeds can be achieved with relatively little technical effort. The cartridges are preferably disposable cartridges that are delivered filled with the appropriate paste and only need to be inserted into a hand-mixing gun.

In order to improve the universal applicability of the hand-mixing gun, reduce the amount of time required for cleaning and facilitate the adjustment for other components, the cloud stamps can be designed as closing devices for the paste cartridges. The piston rods are then only in contact with the push pistons. As the push pistons remain in the cartridges and together with these are possibly designed for single use, there will be no possibility of contamination of the gun on the drive side.

In an embodiment of the invention, it is for the achievement of, an i

in a particularly simple arrangement, it is advantageous that the drive motor - possibly via an intermediate drive - drives the variable transmission; which affects the piston rods via two driven bodies. Then both; driven bodies are driven by the same drive device and ratio

between the piston rods' forward feed speeds is determined, this ratio is ensured even if the drive motor's speed is reduced as a result of flow resistance etc.

The variable transmission is advantageously has no: or little slur. It can e.g. be designed as an exchange drive. In order to simplify the operation of the gun according to the invention, it is proposed according to the invention to use a switchable wheel exchange ("schaltbares Raderwechselgetrie-be"), a continuously variable regulation exchange (so-called PIV exchange) or an exchange with transmission elements, which are interchangeable with other transmission elements to achieve of a different turnover ratio. It is in principle possible to influence the piston rods by means of carriers, chain traction devices or push arms. In further embodiments of the invention are. however, it is advantageous that the piston rods are designed as toothed rods or threaded rods, so that the piston rods themselves form transmission elements in the exchange.

As the advance ratio of the two piston rods is independent of the speed of the drive motor, according to a further

advantageous embodiment of the invention that the drive motor is a variable speed motor, so that the output of two-compo-! nent the paste through the gun's outlet nozzle can be adapted to the relevant working conditions without difficulty and thus an even more universal applicability of the gun is achieved.]

The drive motor can be a motor with an optional speed, where one transmission, if necessary, ensures the suitable speed for the exchange or the toughness of the paste used. Possibly! in connection with the transmission, a regulating exchange can also be arranged, so that the above-mentioned, advantageous speed change can also be achieved by using an engine with an essentially constant speed. in

i 1 In line with the simplification inherent in the task, i

in it is proposed within the framework of another embodiment of the invention that the drive motor is a compressed air motor, as such a motor with a relatively small construction size produces the high drive power that is necessary to push out tough paste or liquid. The compressed air motor can also be equipped with a quantity control valve for speed control.

When one of the two pistons using the gun has reached the end of its range of motion, the piston can be driven back by reversing the direction of rotation of the drive motor - possibly with the help of a reversing gear to enable replacement of the cartridges. Due to the fixed extension relationship between the two piston rods, the other piston, or at least the associated piston rod, will also move back to the starting position. As one of the two cartridges will still be quite full at high mixing ratios, in another embodiment of the invention it is proposed that at least one piston rod is detached from engagement with the drive device and withdrawn independently of this for replacement of a paste cartridge. In this case, one piston, which is in the not yet emptied cartridge, will remain in its position while the piston rod which is assigned to the other piston is released from the engagement, the grip with the associated gear and retracts freely.'After replacing the empty cartridge the piston rod is placed back on the piston base for the cartridge in question and the drive engagement between the piston rod and the assigned gear is restored, in

When the engagement for both piston rods can be loosened, material delivered in this way in cartridges during longer working hours can be used up completely at any time. This happens completely independently of the filling quantity in the cartridge and the mixing ratio set for each time.

With certain, easily mixable components, it may be possible to achieve good mixing when the two pastes flow together at an angle in the mixing tube. If components are also to be used which are more difficult to mix, it is proposed according to a further embodiment according to the invention that the mixing tube in the part near the outlet nozzle, through which both pastes flow, comprises a spiral-shaped mixing spindle, which can be stationary arranged in the mixing tube and ensures reliable mixing of the two paste components. For particularly good mixing, it is advantageous to use a mixing spindle which can be driven for rotation and which is preferably driven by a separate motor, in particular a compressed air motor.

In order to prevent one of the components, e.g. emerges from a leaky place and thus not only contaminates the gun, but also leads to an incorrect mixing ratio, according to the invention it is also proposed that the cartridges at the outlet opening each have their own threaded connection which is screwed together with the associated mixing pipe section, so that reliable sealing is achieved .

Screwing together can e.g. spoon using a cap nut. According to another design of the invention, the connection parts of the mixing tube can also be internally threaded for screwing in the cartridges' threaded ends. These designs of the invention contribute to constructive simplification, as it may then be sufficient that the only effective attachment for the paste cartridge in the gun, apart from the holding effect exerted by the piston rod as a result of the engagement with the discharge piston. easy, is created using the threaded socket, which can be quickly and easily screwed into the nut threads in the mixing tube or into the cap nut by hand. However, particularly when using tough pastes I, it is advantageous that the pasta cartridges are also secured against bending to the side at the opposite end.

According to another embodiment of the invention, the mixing pipe is

designed as a disposable injection molded part, which can simply be removed from the gun when both paste cartridges are unscrewed. This avoids an expensive cleaning process, and it is also possible to process pastes that harden in a relatively short time. If the curing time is accidentally exceeded during a working

during a break, it is enough to replace the mixing tube, and the work can be done

go without it. major interruptions. j

i Especially when using a driven mixing spindle, it is advantageous that the part of the mixing tube which accommodates the spindle is releasably arranged on the remaining part, e.g. by means of a bayonet lock, so that simple cleaning or possible replacement of as few parts as possible can take place.

In order to be easier to handle, the mixing gun according to the invention preferably comprises a handle, which is equipped with a trigger for the drive motor for the feed pistons and possibly with the motor for the rotatable mixing spindle. This handle is advantageously designed as a pistol handle, where a trigger forms the trigger for the motor(s).

In a further embodiment of the invention, the part which accommodates the cartridges is provided with a holding plate, arranged across the cartridges where guide openings are preferably designed, which grip around the ends of the cartridge and are suitable to resist the cartridges against lateral bending. This also enables the use of highly viscous pastes, which require significant forces for squeezing.

If a cartridge is to be replaced while the gun is in use, the mixing tube remains in place, and it is therefore necessary to design the drive device so that it allows the removal and insertion of a cartridge from behind through the relevant guide opening. For this purpose, the drive motor is preferably arranged in front of the holding plate, preferably between the two cartridges

If the exchange is a switchable wheel exchange, it is possible to quickly change the feed speed conditions for the two cartridge pistons. As, however, work is often carried out for a long time with the same mixing ratio, particularly fast switching is of less importance in this case. In a further design of the invention, it is therefore proposed that exchange; gene includes conversion elements that are exchangeable for corresponding elements with a different conversion ratio. Such conversion elements can be carried in a suitable toolbox and selected before the start of more extensive work tasks.' The above turnover ratios can be created by a combination of relatively few turnover elements.

In another embodiment of the invention, it is particularly advantageous that a drive element pair is chosen as the conversion element, which consists of a threaded screw and a threaded spindle,<:>which in turn forms the piston rod. Changing the turnover ratio is achieved by using a threaded spindle and a drive nut with a different thread pitch.

This drive nut is advantageously fixed centrally in a gear wheel at all times, which at all times has the same pitch and number of teeth. In the hand-mixing gun according to the invention, two such gears are arranged, both of which mesh with an associated drive and thus rotate in the same direction. The two gears with their associated threaded bushings and threaded spindles can be interchanged.

Each such gear wheel is advantageously rotatably fixed in a gear carrier which is releasably arranged on the back of the holding plate. The gear carrier is advantageously pivotable about a transverse axis in such a way that it can be attached to the holding plate with both its front and back sides. The special advantage of this i

in execution lies.in the ratio that when the threaded spindle which

forms the piston rod, is fully extended when an empty cartridge is assigned, it must be turned all the way back after inserting the new, full cartridge, but must only be turned together with the gear carrier. It will then be sufficient with a short jus-! tering of the other end of the threaded spindle projecting ' in the direction of the cartridge, so that the hand-mixing gun according to

the invention after refitting the gear carrier must be operational again.

In order to avoid inaccuracies, the length of the threaded spindle is precisely dimensioned so that after removing the gear carrier, replacing the cartridge, swinging the gear carrier with the threaded spindle and repeatedly attaching the gear carrier, it is again in precise engagement with the piston.

Here, simple precautions ensure that the threaded spindle essentially always remains untwisted, as a turning of the threaded spindle in relation to the cartridge would lead to a distortion of the selected conversion ratio between the threaded bushing; singe and thread spindle, which is determined on the basis of the thread pitch.

The gear carrier is formed with the advantage of two hollow cylindrical and similarly designed carrier rings, which via the gear and the threaded bushing are axially immovable, but rotatably connected•

The short surface of each carrier ring is advantageously equipped with one or more, preferably two undercut arc grooves, which, to create a bayonet lock, engage with a head-like motor gear, which is preferably arranged on the holding plate in the form of a screw.

If a large number of gears are used, in order to enable a very large number of mixing ratios, it may also be advantageous to arrange the arc grooves in the holding plate and place the counter projections, which are simpler and easier to mount, on the relevant carrier ring.

When using such carrier rings, which are provided on the outside with: handle, e.g. in the form of a knurling, the foot circle diameter for the associated gear wheel is appropriately chosen to be larger than the outer diameter of the carrier ring, so that attachment or turning 1 and 1 in the replacement of the gear carrier is possible without this engaging the driving gear.

in

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i As mentioned above, the mixing spindle can advantageously be- turn-'

in bar and preferably be connected to a separate drive device! for turning. The drive device is advantageously a compressed air motor and is supplied with compressed air through a separate air line

or one that also supplies the drive motor for piston advancement.

i The rotating spindle is advantageously located in a pipe section, which is arranged on the front of the mixing pipe and which is for cleaning or replacement possibly together with the rotatable

in mixing spindle, e.g. is also easily releasably attached to the mixing tube by means of a bayonet lock. Advantageously, all parts of the mixing pipe that come into contact with the mixture of the two components are also easy to detach and dismantle or replace.

The object of the invention is described in more detail with reference to some examples of execution which are shown in the attached schematic drawing, where

fig. 1 partly in section shows a schematic embodiment of the hand-mixing gun according to the invention,

fig. 2 shows an elevation of another exemplary embodiment.

fig. 3 is an elevation, partly in section, of the embodiment according to fig. 2,

fig. 4 is a schematic representation of a drive device for a hand-mixing gun according to the invention,

fig. 5 is a schematic view of a further embodiment of the hand-mixing gun according to the invention,

fig. 6 shows a partial longitudinal section of the driving part of the embodiment according to fig. 5 on a larger scale,

fig. 7 shows a partial elevation in the direction of the arrow VII in fig. 6, and i

fig. 8 shows a partial longitudinal section through the mixing part of

the design example according to fig. 5, on a larger scale.

i In the figures, the same reference number at all times denotes equal or, functionally, equal parts.

In fig. 1 shows a highly schematic view, partly in section, of a hand-mixing gun, such as e.g. is suitable for applying a two-component polyurethane-based adhesive or a | two-component polysulphide sealant.<!>

Two mutually arranged, circular-cylindrical paste cartridges 1 of the commercial type are with their front, open end screwed into corresponding connection parts for a mixing tube 4. The two connection parts join symmetrically to a tube part, which is arranged in the middle between the cartridges, and in which a mixing spindle 5 in this embodiment is. permanently placed. The mixing spindle 5 here consists of one behind the other, alternating oppositely directed, spiral-shaped partitions and causes an intense mixing of the two paste components that flow out of each cartridge 1. The mixing tube 4 ends in an outlet nozzle 6.

The rear ends of the cartridges 1, which are made of plastic, are open.

In each cartridge 1, a delivery piston 2 is displaceably and sealingly arranged in a known manner. On the piston side facing the rear end of the pasta container 1, there is a rotatable and coaxially arranged with the pasta container 1, as well as displaceable piston rod 3, which rests against the piston. 2.

Both piston rods 3 pass through a transmission 8, on the rear end of which a motor 9 is arranged. The piston rods 3, the transmission 8 and the motor 9 together form a drive device 7, which together with the pasta containers 1 is arranged on a common holder, not shown. The two piston rods 3, which are designed as threaded spindles, stand in the interior of the gearbox in form-matched engagement with exchange parts, and the turnover ratio between the two exchange parts which are assigned to each piston rod can be changed by means of a control knob 15.

In fig. 2 shows an embodiment of a hand-mixing gun. The basic principle is the same as shown in fig. 1.

A receiving part or holder 10, which on the back carries the drive device 7 and on the underside has a pistol handle 11, is provided with two trough-like depressions, where a plastic cartridge 1 of the commercial type can be placed in each depression. The cartridges 1 are each provided with their own at the ends facing the mouth. threaded connection 16, which can be screwed sealingly into internal threads 17 in the mixing tube 4. The mixing tube 4 is pushed from the front into slots in a perforated wall in the holder 10 and is only held in place by being screwed together with the cartridges 1.

The two cartridges, which are identical at all times, are internally closed with each a separate piston 2, and when in use. the corresponding plate-shaped front end of the piston rods 3 will push against each piston 2.

The exchange 8 is provided on the upper side with a switch lever 15 for selecting the feed ratio or the mixing ratio for the two pastes. There are six setting options, e.g. calculated for the conversion ratios 10/1, 7/1, 5/1, 3/1, 2/1 and 1/1 between the displacement speeds of the piston rods.

On the back of the exchange 8, an air motor 9 is arranged in the middle between the two piston rods 3, which via an air line 13 is connected to an air dosing valve (not shown), which is arranged in the interior of the pistol handle 11. A trigger 14 is arranged for operating the air dosing valve.

The valve's second connection is connected to an air hose 12. i

in l

Fig. 3 shows a section of the two pasta cartridges 1, showing how they are placed in the holder 10 and screwed together with the internal threads 17 in the mixing tube 4. It appears that the two pasta cartridges 1 are filled, as both piston 2 is in the rear end position.

: • i In the mixing pipe 4 there is a mixing spindle 5, which is designed in the same way as the design example shown in fig. 1.

It appears that the mixing tube 4 can be removed without further ado, after the two pasta cartridges 1 have been removed.

The mixing tube 4 is designed as a plastic part for one-time use.

The exchange 8 can e.g. be designed as a traction wedge exchange ("Ziehkeilgetriebe") 18 with a driving part 19 and a driven part 20. The driven part 20 carries a set of step-down gears, which are rotatably connected to a shaft 21. The driving part 19 carries a complementary set of gears, which in a known manner can be individually brought into turning engagement with the associated shaft 21 by means of a traction wedge. For changing the traction wedge, a coupling sleeve 22 is arranged, which is displaceable via a rod system (not shown).

The shaft 21 is driven via a worm gear 22, which in turn is connected to the drive motor (not shown). A drive 23, which operates via a piston rod 3a, which is designed as a toothed rack, is firmly connected to the shaft 21. The second piston rod 3b' is driven under intermediate coupling by an intermediate drive 25 of the driven part 20 of the exchange 18.

It will be obvious that a change in the turnover ratio in the pull-wedge exchange also entails a corresponding change in the advancement of the two piston rods 3a, 3b.

Each piston rod 3a, 3b, which is designed as a rack,

is, by means of a pressure roller 26a or 26b, held in engagement with associated driving drives 23 or 25. The pressure roller 26a or j 26b can be locked in the position shown in the drawing and can be swung away from the associated j piston rod after the locking has been released in the direction of the arrow shown. In the swung away position of the relevant part 26a or 26b, the associated piston rod 3a or 3b can be lifted out of engagement with the associated drive 23 i or 25 and withdrawn individually, without the drive engagement j of the other piston rod having to be loosened or a change . of the turnover ratio is necessary.! When one of the two paste cartridges 1 is empty using the mixing gun shown, while the other still contains paste, loose-| nose. the pressure roller 26a, 26b for the piston rod 3a, 3b which is assigned to the empty cartridge from the locking. The stem-<!>fur rod in question is lifted up by the engagement with the drive 23,25 and pulled back <1>so far that the empty pasta cartridge 1 can be taken out. One When a new cartridge 1 is inserted, the piston rod is again pushed forward until it abuts against the piston 2 and the associated pressure roller 26a, 26b is locked, so that the piston rod is pressed into engagement with the associated driving drive 23, 25. Work can now continue without disturbance of the mixing ratio.

Fig. shows a schematic design example of the hand-mixing gun in elevation.

This hand-mixing gun comprises a holder 10, similar to the embodiment according to fig. 2, on which a handle with a trigger is arranged (not shown in fig. 5).

In contrast to the embodiment in fig. 2, the two parts of the embodiment according to fig. 5 arranged with a greater distance between them so that the compressed air motor 9 can be arranged between them.

At the front end of the hand-mixing gun shown, a mixing pipe 4 is placed, which opens into a pipe connection 4', where the mixing spindle 5 is arranged, as more clearly shown in fig. 8.. In contrast to what was the case with the above-mentioned design example, the mixing spindle 5 is rotatable and sits j on the shaft of a compressed air motor 29, which is arranged flush<j>with the compressed air motor 9 between the two cartridges 1 on the side of the mixing pipe 4 which faces away from the spigot 4'.The outlet nozzle 6 is arranged at the front end of the pipe spigot 4'.

The mixing pipe 4 on one side and/or the spigot 4' together. the outlet nozzle 6 forms - possibly together with the mixing spindle 6 - a replaceable or disposable part, which is attached to the holder 10 or the mixing tube 4 by means of a suitable connection, see, e.g. a bayonet lock. Thus, the parts that come into contact with the reaction-forming mixture of the two pastes] which are arranged separately in the cartridges 1 can be easily removed and thus either taken apart and cleaned or replaced.

In the area of the rear ends of the cartridges 1, a holding plate 29 is arranged across the cartridges. The holding plate 27 is firmly connected to the holder 10 and carries the drive motor 9 on the side facing the mixing pipe 4. The shaft 30 of the motor 9 passes through the holding plate 27 and carries a drive 31 on its free end, outside the holding plate.

The drive 31 meshes with two gears 32, which are arranged coaxially with each cartridge 1 and are rotatably stored in a gear carrier 28, which is removably fixed on the holding plate 27. The drive arrangement will be discussed in more detail with reference to fig. 6 and 7.

From fig. 5 also shows the air line 13 to the compressed air motor 9 and a further air line 13' to the compressed air motor 29. Both air lines 13, 13' can advantageously join a compressed air supply pipe (not shown).

The gear carriers 28, the gears 32, the piston rods 3, which are arranged coaxially with the tooth cavities 32 and designed as threaded spindles and the drive 31 form parts of the exchange 8, ; which is shown in more detail in fig. 6. As shown in fig. 6, there is a threaded bushing 33 in the middle of each gear wheel 32 and attached coaxially with it, which is in threaded engagement with the threaded spindle .3 which forms the piston rod.

The gear carrier 28 is formed by two identical, oppositely placed carrier rings 28a, 28b, which are knurled on the outside and have a slightly smaller diameter than the associated gear 32 tooth base circle.

in diameter..

Each carrier ring is designed as a hollow cylinder, the bottom of which is pierced, so that the threaded bushing 33 with its cylindrical exterior can penetrate the two bottoms of the carrier rings 28a,i 28b with guidance, but rotatably.!

The outer surface of the threaded bushing 33 has a perforation, where; a spring ring is placed so that it barely protrudes above the bottom of the relevant carrier ring 28a, 28b, so that rotation of the threaded bushing 33 in relation to the carrier rings 28a, 28b does not; is prevented, but that the axial clearance of the threaded bushing 33 in relation<:>to the carrier rings is reduced to a minimum. j

The inner diameter of the carrier rings 28a, 28b essentially corresponds to the outer diameter of the cartridge in such a way that it can be pushed into the carrier rings.

On each short side, the carrier rings 28a, 28b have two mutually opposite arc grooves 34, which extend over a circular arc of approx. 90° and mutually opposite mouths in a circular opening 35, which has a larger diameter than the width of the arc groove 34.

As clearly shown in fig. 6, the arc groove is designed with a T-shaped, undercut cross-sectional profile.

The holding plate 27 is flush with each cartridge 1 equipped with a guide opening 36, the diameter of which is adapted to the outer diameter of the cartridge and dimensioned so that the cartridge can be inserted without difficulty through the relevant guide opening 36.

i On both sides of the guide opening 36 and opposite in relation

to the two openings or the extensions' 35 of the arc grooves 34, a threaded bore is provided at all times in the holding plate 27, where a screw is screwed in so far from the gear carrier side and has a cylindrical head with such a dimension that the carrier ring 28a or 28b with the extensions 35 of its arc groove 34 as far as can be slipped over the screws 37 and then turned 90°, so that the heads of the screws 37 grip under the arc groove profile and the arc grooves 34 and the screws 37 together form a bayonet lock. j

IN

i As mentioned above, the threaded bushing 33 and the gear wheel 32 j are rigidly connected to each other and arranged to be rotatable in relation to the carrier rings 28a, 28b. For the carrier rings 28a, 28b, a material has been chosen which, assigned to the threaded bushing's 33 and ! the material of the gear wheel 32 provides a self-lubricating effect, so that the gear wheel 32 and the threaded bushing 33 are maintenance-free and rotatably stored within the carrier rings 28a, 28b. '

The inner opening of the carrier ring 28a and the guide opening 36 in the holding plate 27 extend at all times flush with each other and form a common receiving member for the rear end of the cartridge 36.

In the case of a slight chamfer of the arc groove 34 in the axial direction, when the gear carrier 28 is pulled onto the holding plate 27, an axial tightening movement can follow, so that the front end of the cartridge 1 is pressed firmly against the mixing tube 4 and so that it is also ensured that the gear carrier 28 does not loosen while the mixing gun is. in use.

Each gear carrier 28 has a threaded bushing 33 and a push rod 3 with the same thread pitch, while the thread pitch is different for different gear carriers 28. As these gear carriers 28 are easily replaceable, it can be done with the help of a series of gear carriers with associated feed rods with different thread pitch, a diversity of mixing ratios is achieved.

When two cartridges are inserted, these are pushed through the guide openings 36 and are taken up tightly with the front side of the mixing tube 4. Then suitable gear carriers 28 for the desired mixing ratio are selected and mounted. In the case of these gear carriers, the piston rod 3 is in an end position and engages with the <!>piston, which is located in the partron 1 interior. Turning off

in the piston rod opposite the piston is prevented with the benefit of a shape-matched engagement, and rotation of the piston in relation to the cartridge wall is prevented by a power-transmitting connection between these parts. If a power-transmitting connection is not sufficient, the piston rods can in addition to threads also have an axial groove, where e.g. a cam on a yoke, which 1 is attached to the free piston rod ends from behind, engages. The cam protrudes at all times from a corresponding internal bore in the yoke, through which the piston rod passes.

When one of the two cartridges is emptied, the corresponding gear carrier 28 is taken out, the empty cartridge is pulled out backwards, towards the guide opening 36, a new cartridge is inserted, the gear carrier is turned over and attached again. The length of the piston rod 3 is consequently dimensioned so that in a fully extended state, with one end inserted into the cartridge, with its other end protruding so far forward from the other end of the gear carrier 28 that when turning the gear carrier and thus the piston rod 3 again comes into precise engagement with the plunger for a new, filled cartridge.

Claims (14)

1. Hand-mixing gun for the simultaneous ejection of two liquids of low to high viscosity. from a cartridge device containing two separate liquids, where a discharge piston is displaceable for each liquid, with a receiving device. for the cartridge device, a mixing tube, to which the outlet openings of the cartridge device can be connected and which comprises an outlet nozzle for the mixed liquids, two piston rods, which can be pushed into the cartridge device from the opposite side of the cartridge device's outlet openings for displacing the output pistons and a drive motor for moving the piston rods, characterized in that the pickup device for the cartridge device is designed for storing two cartridges next to each other and that a variable exchange (8) is arranged, which, in order to create a desired mixing ratio between the two liquids, allows the operation of the two dispensing pistons (2) with dispensing speeds with a predetermined adjustable mutual relationship. 2.. Gun as specified in claim 1, characterized in that the drive motor - possibly via an intermediate drive - drives the variable transmission, which displaces the piston rods (3) via two driven bodies and where the ratio between the two piston rod speeds is mutually variable. 3.. Gun as specified in claim 1 or 2, characterized in that the transmission (8) is a wheel transmission comprising several transmission elements or coupling steps. 4. Gun as specified in one of claims 1-3, characterized in that the piston rods (3) are threaded spindles, are non-rotatably guided and can be operated by axially fixed, drivable drive nuts (33). 5. Pistol as stated in one of claims 1-4, characterized in that the engagement between at least one piston rod (3) and the other part of the drive device (7) is detachable and that this piston rod can be withdrawn, independently of the other drive device for replacement of a cartridge (1). 6. Gun as specified in one of claims 1-4, characterized in that the mixing tube (4) in the part which is close to the outlet nozzle (6) and through which both liquids flow is provided with a mixing spindle (5) for better mixing. 7. Pistol of the type specified in one of claims 1-6, characterized in that the cartridge receiving part (10) in the area of the ends of the cartridges (1 <i> ) which are opposite in relation to the outlet openings comprises a retaining plate (27), which is arranged across the cartridges (1) and on which the motor (9) is arranged between the two cartridges (1) on the side of the holding plate (27) that faces the cartridges. : 8. Pistol as stated in claim 7, characterized in that the holding plate (27) comprises guide openings (36), which receive the cartridges (1) in their end parts. 9. Gun as stated in one of claims 4-8, characterized in that a central driving gear (31) engages with two identical, replaceable gears (32), each of which carries a centrally arranged threaded bushing (3), which is rotatable connected to the gears and which has an internal thread, which matches the relevant external threading of the piston rod (3) which is designed as a threaded spindle, where the piston rods in turn are non-rotatably guided. 10. Gun as stated in claim 9, characterized in that the gears (32) are rotatably stored in a gear ' carrier (28), which is releasably fixed in the holding plate (27) and which is symmetrically designed to the center plane of the gear wheel (32) and which, after release from its attachment to the holding plate (27) and turning 180° about a turning axis which runs across the gear axis can be attached to the holding plate (27) again. 11. A gun as stated in claim 10, characterized in that the gear carrier (28) is formed by two hollow cylinder-shaped carrier rings (28a, 28b), which on the outside is provided with a handle, on its upper end surface has an engagement groove (34) for a bayonet lock with motor claws (37) on the holding plate (27) and between its opposite bottom surfaces i ter encloses the gear wheel (32), with which they are rotatably connected, and that the outer diameter of the support rings (28a, 28b) is smaller than the gear wheel (32)'s foot circle diameter. 12. Pistol as stated in claim 11, characterized in that the inner diameter of the hollow cylindrical carrier rings (28a, 28b) corresponds to the diameter of the guide opening (36) and is sized to receive a cartridge (1). 13. A gun as specified in one of claims 4-12, characterized in that the length of the piston rods (3) is dimensioned so that, when they occupy the first end position with one end of a completely emptied cartridge (1), after swinging of the gear carrier (28) but its other end takes the other end position that exists with a full cartridge. 14. Gun as specified in one of claims 1-13, characterized in that the mixing spindle (25) is rotatable and connected to a rotation drive device (29).