FR2526070A1 - Extrusion gun for mastic - has coupling which prevents continuation of mastic flow when handle is released - Google Patents

Abstract

The extrusion gun for mastic comprises a handle (4) at the rear of a cartridge holder (1) and a plunger (7) which passes through holes in two spring-biassed plates (6,9). When squeezed, the handle tilts the first plate (6) which grips the plunger (7) forcing mastic out of the gun. When the handle is partially released, the first plate moves back along the plunger which is held stationary by the second plate allowing the action to be repeated. However, when the handle is fully released, the second plate is released from the plunger by a bar (12) extending from the handle, preventing wastage when the gun is not in use.

Description

- ,, 1

  * ', _ The present invention is domai-

  do extrusion devices called extruder guns,

  particularly in the finishing works of the building

  :, intended to extrude from a cartridge a pasty material which

  tituent a seal or caulking, it should be understood that this area of use although being the most

important is far from being the only one.

  Hand-operated extruder guns are well known in particular by EUA patents 1 986 166, 2 420 203, 2 530 359, 2 562 825, 2 582 156, 2 602 570, 2 602 571, 2 732 102, 2 786 604 and 4,081,112 (CHANG) 'These devices generally include a rod

  piston function which, operated by hand by means of

  diary of a lever comes to put pressure on the material vis-

  queuse contained in a cartridge; these devices include

  both in general means for prohibiting rearward movement of the rod when the manual pressure ceases; he

  * there arises a disadvantage of some importance, except

  -see, that a certain subsequent quantity of viscous material-

  -20 continues to flow through the orifice of the cartridge when the manual pressure ceases Some devices, such as that of the CHANG patent offer the possibility of avoiding this subsequent flow by a voluntary action of the thumb for example on certain parts of the device however this voluntary action requires some attention and well

  ", this operation is often forgotten at the end of use.

  j ,: -We therefore sought to make automa-

  tick this action avoiding this subsequent flow; thus, a device described in a patent FR 2 284 728 (EUA priority n 484 532, C R COSTA and R L SMIGEL) is provided with a floating dog recalled in front by a so-called traction spring; however due to difficulties in balancing the force of the spring with that of other springs of the device, stopping

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  automatic subsequent flow is very random.

  The object of the present invention is to propose improvements to the devices of the prior art, in particular to that described in EUA patent no. 4 081 112, but not exclusively to this, aiming at i f

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  prevent automatic, simple and effective flow

subsequent.

According to the present invention, a

  hand-operated extrusion device of the type

  taking a cradle intended to receive a cartridge, a

  handle integral with said cradle, a lever, in the shape of a

  chette, articulated on the handle, a plate, called plunger,

  arranged at 1 *, I have a rod that can slide axially-

  ment in said cradle, coupling means, in the form of plates, which can be made integral with the rod under the effect of the thrust of said lever against a spring, called compression, which tends to separate said coupling means when the lever pressure ceases, means for preventing rearward movement of the rod when ceases

  the pressure of the lever on the plates, said means of inter-

  diction being made up of a piece called "dog" having a hole through which the rod passes, said "dog" being

  take either a position perpendicular to the rod to

  put the sliding of it in the hole, a po-

  inclined sition on the rod in which the return back of the rod is prohibited, said device further comprising means for axially releasing the rod when the manual pressure ceases, in order to avoid a subsequent flow of the extruded material is characterized in its general in that said means for preventing the subsequent flow consist of connection means between the trigger and the dog, said connection means having a maximum length beyond which a forward movement of the trigger causes the placing the dog in the perpendicular position

  to the rod, position in which the rod is released axially-

  is lying. It follows from this provision

  general that the trigger, in the absence of any ma-

  Coming spontaneously forward, the cessation of a manual effort automatically leads to the release of

  the rod and thereby prevents any flow of material to be extruded

  due to the cessation of manual pressure.

  According to a first form of reaction

  remarkable for its simplicity, said connecting means consist of a rigid bar articulated at one of its ends on said trigger, its other end passing through a hole made in the dog, said end being provided with means of stop intended to come into contact with the dog when the trigger is in the released position.

  Preferably said rigid bar

  of in the shape of a pin pin whose ends

  are curved to form a stop, advantageously a round

  the perforated one is arranged in the vicinity of the end

bent of said pin.

According to another form of realization

  1.5 a little more complex but applicable to practically all cases of production of extrusion devices of the aforementioned kind, said connecting means consist of a flexible cable, preferably arranged in a sheath over part of its length, said flexible cable being anchored on the one hand to the trigger and on the other hand to the dog; preferably

  at least one of said anchors is a stop anchor,

  ie uh anchor with play, -in which the cable can circulate freely in a hole of the trigger or the dog until a ferrule crimped of the cable comes to be applied against one of these holes, the length of the cable being such that the fully released position of the trigger causes the placement of the

  dog in the position perpendicular to the rod.

  Advantageously, but incidentally, the improved devices according to one or the other embodiment of the invention will be provided with an additional return spring tending to bring the trigger forward when the manual pressure stops. ; this additional return spring may be either a spring

  helicoldaldisposed around the bar or around an ex-

  end of the cable between the trigger and the handle, i.e.

  hairpin spring arranged for a first part inside

  laughing handle and for a second part inside

of the trigger.

2526070-

The present invention will be better

  understood and details will be shown below

  description which will be made of two embodiments in relation to the figures of the appended plates in which: FIG. 1 is a sectional elevation of a device provided with a dog having an apparent thumb support at the rear of the handle, said device comprising the improvements of the invention and being in a position for automatically stopping the subsequent flow, FIG. 2 is an illustration of the same device occupying a position in which manual pressure is exerted on the trigger , Figs 3 and 4 illustrate a

  second embodiment with cable and sheath.

  In FIGS. 1 and 2, a device to which apply, in their first embodiment,

  improvements of the invention is mainly cons-

  with a cradle 1, attached to a handle 2, in which

  the is articulated around an axis 3 a lever in the shape of a

  chette 4; the upper end 5 of the trigger takes a sliding support on a plate 6 then pushes this one forward when the trigger is brought closer to the handle

  <(fig 2); a rod 7 whose front end in the form of a

  tone has not been shown, passes through a bore in plate 6; when the plate 6 is pushed forward by the head of the trigger 5, it inclines slightly on the rod and the edges of the hole bite into the rod:

  the rod 7 and the plate 6 are then integral with one of the

  tre and move forward against a spring

compression 8.

When manual pressure stops

  on trigger 4, spring 6 returns the plate backwards

  that 6 which circulates freely on the rod and the head 5 of the trigger.

The rod 7 during the movement of re-

  ass of plate 6 does not follow the latter in its movement

  ment because it is locked in its position by a part 9, called dog, constituting a means of prohibiting the rear movement of the rod; the operation of this part 9 is similar to that of the plate 6; the dog has a hole

  through which the rod passes; the dog is kept nor-

  badly inclined on the rod by a spring; when the rod is pushed forward by the trigger, it tends to place the dog in a position perpendicular to it, position in which the rod circulates freely in the hole of the dog as soon as the rod stops in its movement towards the 'front, the edges of the dog hole 9 tend to bite into the rod, which has the effect of stopping the rod in a backward movement.

To avoid subsequent flow

  quent of pasty material, provision has been made to extend the dog 1 S outside of the handle by a tail which forms a support for the thumb; subsequent flow is avoided by pressing

  on the tail there as soon as one sought the manual effort.

  These are arrangements known from the prior art.

  According to a first form of reaction

  Reading of the invention, provision has been made to connect the part II of the dog 9 by connecting means constituted by a rigid bar 12 articulated at its end 13 on the trigger, while its other end passes through a hole 14 made in part 11 of the dog; this second end is provided with a stop means such as a washer 15 intended to enter

  in contact with part 11 of the dog.

The length of the bar 12,

  that is to say the distance between its point of articulation

  tion and the washer 15 is such that the return to the front position, or released, of the trigger causes the washer 15 to come into contact with the part II of the dog and then to push the latter forward until the dog is in a position, close to the perpendicular, in which it

  is detached from the rod 7 (fig 2).

  This action of the bar on the dog is equivalent to the action of the thumb on the tail of the dog but it is done automatically and systematically

  when the user has released the trigger.

The implementation of the perfect-

  ment on the very well-known model shown in the figure is made in a very simple way by punching a hole 14 in the

  tail of the dog and a hole 16 in the rear face of the poi-

  gné, by perforating two holes in the trigger and by setting an axis 13 there, by placing a pin pin 12 around the axis, this pin or bar 12 passing through the holes 15 and 16, then finally by bending the ends of the pin 12 at well defined points after having

  possibly passed around the pin a washer 15.

Note in the figures pre-

  cédentesun helical spring 17 additional return disposed between the trigger 4 and the handle 2, in the interior recess of these parts, this spring being intended to bring the trigger forward, in cases where the spring 8 would be of a insufficient strength. In fig 3 and 4, fig 4 being a top view along a section AA of the pistol of fig 3, another device, or extrusion gun is of a model

  substantially different from that of Figs 1 and 2; according to this mo-

  the part constituting the means of prohibition of the rear monuvoeent

  re of the rod 20, is a part 21, also called a dog, by analogy of function with the dog 9 of FIGS 1 and 2, which also has a through hole for the rod; but in this model the dog crosses the lateral face 22 of the upper part of the handle 23, through a window 24, to appear

  on the side of the handle, in a protruding part 25 (ana-

  the tail of the dog 9); this protruding part 25

  is intended to receive pressure from the thumb to make these

  prohibit the rearward movement of the rod when

  the trigger 26 was stopped.

  -The means of the invention to replace this pressure of the thumb and make the transfer of the ban automatic, consist of a flexible cable 27 disposed under a sheath 28, over part of its length the cable 27 is anchored to one of its ends on one leg 29

  of the trigger, and at its other end to the protruding part

  te 25 of dog 21; these anchors are simple holes in the lug 29 and in the dog 21, in which the cable passes which has at each of its ends a crimped end piece, such as 30 and 31, which abuts against the lug 29 and the

dog 25, respectively.

  The sheath 28 itself comes to bear at one of its ends against a lug 32 of the handle 23, and at its other end against another lug 33 of the lateral face 22; the support legs 32 and 33 of the

  sheath are arranged opposite the cable anchoring points.

  It should therefore be understood that the length of the cable (between

  its tips) is such that when the trigger 26 is in position

  sition before, or released, the tip 31 comes to press on the protruding part 25 of the dog 21 and slightly pulls it forward; this traction automatically replaces the pressure of the thumb. It will thus be understood that this variant of the invention is applicable to practically any type of pistol comprising a trigger, a

  rod and a dog having the above-described functions.

  Although we have described and depicted

  felt two variants of application of the invention, it should be understood that the scope thereof is not restricted

  to these variants, but that it extends to any means, including

  both the general characteristics set out above,

  determined to end the ban on rearward movement of

the stem.

R E V E N DICATIONS

  1. An extrusion device which can be operated by hand of the kind comprising a cradle intended to receive a cartridge, a handle integral with said cradle, a lever, in the form of a trigger, articulated on the handle, a plate, called a plunger, disposed at the end of a rod that can

  smoothing axially in said cradle, means of coupling

  securely, in the form of plates, which can be made integral

  res of the rod under the effect of the pushing of said lever against a spring, called compression, which tends to separate said coupling means when ceases

  the pressure of the lever, means of prohibiting movement

  back of the rod when the lever pressure stops

  on the plates, said means of prohibition being cons-

  with a so-called "dog" part comprising a hole through which the rod passes, said "dog" possibly taking a position perpendicular to the rod to allow it to slip in the hole, or an inclined position on the rod in which the return in

  rear of the rod is prohibited, said device

  further providing means for axially releasing the rod

  when the manual pressure stops, in order to avoid a

  Lement subsequent extruded material, characterized: in that said means for preventing the subsequent flow are constituted by connecting means between the trigger and the "dog", said connecting means having a maximum length beyond which a forward movement of the trigger causes the placement of the "dog in the perpendicular position

  to the rod, position in which the rod is released axially

  Lement, from which it follows that 1 the trigger,

  in the absence of any manual pressure returning spontaneously-

  forwards, the cessation of a manual effort automatically leads to the release of the rod and thereby avoids

  any flow of material to be extruded subsequent to the cessation

manual pressure.

  2. Device according to claim 1, characterized in that said connecting means consist of a rigid articulated bar

  at one of its ends on said trigger, its other end

  moth passing through a hole in the "dog", said end being provided with abutment means intended to come into contact with the "dog" when the trigger is in the released position -3. Device according to claim 2, characterized

k in that said bar rigid-

  of has the form of a pin pin whose ends are curved to form a stopper 4. Device according to claim 3, characterized by the presence of a perforated washer in the vicinity of the curved end of said pin a 5. Device according to claim 4, characterized by the presence of an additional return spring tending to bring the trigger forward when the manual pressure ceases 6. Device according to claim 5, characterized in that said return spring is a helical spring arranged around said bar; 7 Device according to claim 6, characterized in that said spring is a hairpin spring arranged for a first part inside the handle and for its second part inside the trigger, said spring passing between the

  trigger and the hinge pin of the bar.