EP2402120B1 - guide for a nail-setting device and device including the guide - Google Patents

Description

The field of the invention is that of devices for fixing nails in a support material. These are devices which allow the nails to be driven by means of a drive piston which is itself propelled by an electric, pneumatic or thermal motor.

Today, the devices in question are most often devices with an internal combustion engine, fuel gas.

• en fait un guide-clou - qu'il faut mettre en appui contre le matériau support pour pouvoir les actionner. Il s'agit de la sécurité dite d'appui. Mais, ce guide-tampon présente donc également la fonction de guider les clous jusqu'au matériau support.

These devices have, at the front, what is called a buffer guide

• in fact a nail guide - which must be pressed against the support material in order to be able to actuate them. This is called support security. However, this buffer guide therefore also has the function of guiding the nails to the support material.

To be properly guided in the barrel of the devices as well as in the buffer guide, the nails are guided in two axially separated zones, the first, at the level of their head, of the same diameter as the bore (of the barrel) and of the guide -buffer, the second, at the level of a guide skirt slipped around their rod and bearing against the wall of the bore.

To better ensure the ejection and expansion of the skirt of the nails on leaving the devices, it has been proposed to hollow out the front end of the buffer guides.

But to solve such a problem, we created another one. With such a hollow structure, the head of the nails is no longer guided over the very last portion of their travel just before the support material, when it opens into the recess of the buffer guide. This is prejudicial to the guarantee of the fixing. The document US2004 / 226976 discloses a tampon guide according to the preamble of claim 1. US3407982 describes another buffer guide.

The invention of the present application aims to solve the latter problem as a whole without however renouncing the solution of the first.

Thus, the invention relates to a buffer guide for a nail fixing device, comprising a bore for receiving a nail comprising a head and a rod on which a skirt is slid, the bore having a passage section determined for that the head and the skirt of the nail ensure its guidance therein, a recess being made in the front part of the buffer guide for the ejection and expansion of the guide skirt, buffer guide characterized in that the recess has a constriction of the same passage section as the receiving bore, whereby the nails remain guided in the bore of the buffer guide until they exit.

The constriction is advantageously formed by at least two radial bulges, diametrically opposed when there are only two, at 120 ° from each other when there are three.

The invention also relates to a nail fixing apparatus comprising a buffer guide, as claimed above.

• la figure 1 représente une vue en coupe axiale d'un appareil de clouage équipé d'un guide-tampon de l'art antérieur, en cours de tir, le clou étant presque en fin de course ;
• la figure 2 représente une vue à plus grande échelle de la partie antérieure du guide-tampon de l'appareil de la figure 1 ;
• la figure 3 est une vue en coupe à très grande échelle de la partie antérieure d'un guide-tampon de l'invention ;
• la figure 4 est une vue en coupe de la partie antérieure du guide-tampon de la figure 3, en cours de tir, le clou étant presque en fin de course ;
• la figure 5 est une vue en perspective du guide-tampon de l'invention, dans une forme de réalisation à trois renflements de rétrécissement et
• la figure 6 est une vue en perspective du guide-tampon de l'invention, dans une forme de réalisation à deux renflements de rétrécissement.

The invention will be better understood with the aid of the following description of the tampon guide and of the fixing device of the invention, with reference to the accompanying drawing, in which

• the figure 1 shows an axial sectional view of a nailing device equipped with a buffer guide of the prior art, being fired, the nail being almost at the end of its travel;
• the figure 2 shows an enlarged view of the anterior part of the tampon guide of the figure 1 ;
• the figure 3 is a sectional view on a very large scale of the front part of a tampon guide of the invention;
• the figure 4 is a sectional view of the anterior part of the tampon guide of the figure 3 , during shooting, the nail being almost at the end of its travel;
• the figure 5 is a perspective view of the tampon guide of the invention, in an embodiment with three tapering bulges and
• the figure 6 is a perspective view of the tampon guide of the invention, in an embodiment with two tapering bulges.

With reference to the figure 1 , a nailing device 1, here with an internal combustion engine 2, of the prior art, comprises a drive piston 3, with a head 4 which can be moved in a cylinder 5 under the action of the firing of the fuel in chamber 6 of the appliance.

The piston rod 7, at the end of the shot, is engaged in the buffer guide 8 after having propelled the nail 9 into the support material 10 intended to receive it. The nail 9 comprises a head 11 and a shank 12. The head 11 has a diameter substantially equal to that of the bore 13 of the buffer guide 8.

A guide skirt 14 is mounted on the shank 12 of the nail. During movement of the nail in the buffer guide 8, the skirt bears against the wall of the bore 13 to guide the nail. In the front part 30 of the buffer guide 8 is formed a frustoconical recess 15 for the ejection and expansion of the skirt 14. This front part is flared towards the front.

In the position of figures 1 and 2 , the nail 9 is not yet completely inserted into the material 10. The guide skirt 14 has emerged from the part of the buffer guide 8 of section corresponding to that of the nail head 11. The skirt 14 has been able to s' expand before the head 11 of the nail crushes it against the support material and can therefore be ejected when the operator takes out the bearing device against the material 10. In the position of the figure 2 , the nail head has just emerged from the bore 13 of determined and constant section and, between this position and the total insertion of the nail, until the head 11 comes against the surface 16 of the material 10, the nail is no longer guided.

With reference to the figure 3 , where the same references designate the same means as on the figures 1 and 2 , one sees in the section plane considered a radial narrowing bulge 17 of the wall of the recess 15 which projects inwardly, towards the axis 18 of the buffer guide, to extend the wall of the bore 13 of the stamp guide, which extends behind the recess 15, to the front end 19 of the stamp guide 8. Although this is not the case in practice, although it is not 'was that this single radial bulge 17 and at least this one, the nail head 9 would continue, during its course through the recess 15 and along this partial constriction 35, to be guided at least in part, so long as at the level of its head 11 than at the level of its guide skirt 14, as can be seen on the figure 4 .

In practice, the recess 15 really has a narrowing 40 of the same passage section as the bore 13 for receiving the nail and in fact comprises several radial bulges.

For the 8 'buffer guide of the figure 5 , the constriction 40 'is formed by three radial bulges 20-22, angularly spaced two by two by 120 °.

On the 8 "buffer guide of the figure 6 , the constriction 40 "is formed by only two radial bulges 23, 24 diametrically opposed.

There could be more, but not too many so that the recess 15 for the expansion and ejection of the nail guide skirt remains.

Claims (5)

1. Plug guide (8) for a nail-setting appliance (1), having a bore (13) for receiving a nail (9) having a head (11) and a shank (12) over which a skirt (14) is slid, the bore (13) having a given and constant circular passage cross section determined such that the head (11) and the skirt (14) of the nail (9) ensure the guidance of the latter therein, a forwardly flared frustoconical recess (15) being formed in the front part (30) of the plug guide (8) for the ejection and expansion of the guide skirt (14), said plug guide being characterized in that the recess (15) has at least one radial protrusion (17) projecting towards the inside so as to extend the wall of the bore (13) in the plug guide and form a nail-guiding constriction (35).
2. Plug guide according to Claim 1, wherein the recess (15) has a constriction (40'; 40") with the same passage section as the nail-receiving bore (13).
3. Plug guide according to Claim 2, wherein the constriction (40") is formed by two diametrically opposite radial protrusions (23, 24).
4. Plug guide according to Claim 2, wherein the constriction (40') is formed by three radial protrusions (20-22) that are angularly spaced apart in pairs by 120°.
5. Nail-setting appliance having a plug guide (8) according to one of Claims 1 to 4.

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