EP4705058A1

EP4705058A1 - Nailer, stapler, or similar device, with shock absorber

Info

Publication number: EP4705058A1
Application number: EP24723561.7A
Authority: EP
Inventors: Andrea Carati
Original assignee: FASCO Srl
Current assignee: FASCO Srl
Priority date: 2023-05-05
Filing date: 2024-05-03
Publication date: 2026-03-11
Also published as: IT202300009012A1; WO2024231309A1

Abstract

A nailer, stapler, or similar device, with shock absorber, comprises at least a sliding element (3), constrained by a guide element (5) to slide in a sliding direction (D), between an initial (I) and a final (F) condition; and an end element (7) fixed adjacent to the position of the sliding element (3) in its final (F) condition. The sliding element (3) comprises a protrusion (11) facing the end element (7), said end element (7) comprising a concave seat (13) of a complementary shape to that of the protrusion (11) and bearing exits (14) for the air trapped between the sliding element (3) and said protrusion (11), the latter being housed, slidingly and in an airtight manner, in said concave seat (13), at least in the terminal section - of a maximum predetermined length (M) - of the stroke of the sliding element (3) towards the final (F) condition. The exits (14) are closed at said terminal section by the sliding element (3), whereby the latter, together with the end element (7) and a portion of the guide element (5), delimits in an airtight manner a compression chamber (15) whose internal volume decreases as the sliding element (3) approaches the final (F) condition, thus effecting a pressure increase that acts on the sliding element (3) and causes it to slow down and/or stop.

Description

NAILER, STAPLER, OR SIMILAR DEVICE, WITH SHOCK ABSORBER

TECHNICAL FIELD

The present invention relates to apparatuses for fixing or fastening staples and/or nails, and the like, and, more specifically, to a nailer, stapler, or similar device, with shock absorber.

BACKGROUND ART

There are known stapling or nailing devices having a sliding element, such as a pneumatic or other type of piston, said sliding element being subjected to a pulse thrust, e.g. generated by compressed air, which the sliding element transfers, directly or indirectly, to staples or nails by imparting to them a speed sufficient for them to be driven, e.g. into wood or its derivatives, or into building materials.

A drawback of these known devices is that the high stresses and accelerations of the sliding element entail stopping impacts and shocks of the related even very intense stroke, which cause wear and damage to said known devices over time.

DISCLOSURE OF THE INVENTION

An object of the present invention is to propose a nailer, stapler, or similar device, having a shock absorber capable of progressively slowing down and/or stopping the stroke of the sliding element, thus avoiding or dramatically reducing the end-stroke impacts of the parts that transmit motion to the nail or staple, thereby avoiding excessive wear and breakdowns.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the invention are highlighted hereinbelow, with specific reference to the accompanying drawings, in which: - FIG. 1 is a longitudinal section view of the nailer, stapler, or similar device, with shock absorber, according to the present invention, in an initial condition immediately preceding operation of the same;

- FIG. 2 illustrates a longitudinal section view of the device shown in FIG. 1, in a condition immediately subsequent to operation, in which a sliding element of the device has travelled about half of its stroke;

- FIG. 3 is a longitudinal partial section view of the device shown in FIG. 1, in a condition immediately subsequent to nail or staple ejection, and with the sliding element of the device being in the terminal section of its stroke;

- FIG. 4 is an enlarged sectional view of two elements shown in FIG. 2;

- FIG. 5 is a further enlarged sectional partial view of the two elements shown in FIG. 4.

BEST MODE OF CARRYING OUT THE INVENTION

Referring to FIGS. 1-5, the nailer, stapler, or similar device, with shock absorber, according to the present invention is illustrated by 1.

The invention is described hereinbelow with reference to a pneumatic gun for ejecting, fastening and/or fixing nails or staples. However, the invention also extends to other pneumatic linear motion devices, where it is useful or necessary to avoid any endstroke impacts of the moving element, even without requiring any buffers or limit switches made of rubber or similar materials.

The device 1 includes at least: a sliding element 3; a guide element 5; an end element 7.

The sliding element 3 is constrained by the guide element 5 to slide in a sliding direction D, between an initial I and a final F condition. The end element 7 is fixed adjacent to the position of the sliding element 3 in its final F condition.

The sliding element 3 comprises a protrusion 11 facing the end element 7, the latter in turn comprising a concave seat 13 of a complementary shape to that of the protrusion 11.

The concave seat 13 has exits 14 for the air trapped between the sliding element 3 and said protrusion 11, the latter being housed, slidingly and in an airtight manner, in said concave seat 13, at least in the terminal section - of a maximum predetermined length M - of the stroke of the sliding element 3 towards the final F condition.

The exits 14 are closed at said terminal section by the sliding element 3, whereby the latter, together with the end element 7 and a portion of the guide element 5, delimits in an airtight manner a compression chamber 15 whose internal volume decreases as the sliding element 3 approaches the final F condition, thus effecting a pressure increase that acts on the sliding element 3 and causes it to slow down and/or stop.

Specifically, the guide element 5 consists of a cylinder of a pneumatic type; the sliding element 3 comprises a piston 4 that slides, in an airtight manner, into the cylinder; and the end element 7 is sealed to the end of the cylinder defining the final F condition.

Moreover, the end of the cylinder of the guide element 5, opposite the end element 7, bears a cylinder closure head 27 having a compressed air inlet valve 29 for operating the sliding piston of the sliding element 3.

In an operational condition of the device 1, starting from the initial I condition of the guide element 5, where the latter is at its maximum distance from the end element 7, the compressed air introduced by means of the corresponding valve 29 between the head 27 and the piston 4 of the sliding element 3, causes said sliding element 3 to travel in the sliding direction D, towards the final F condition. When the piston is close enough to the final F condition, the protrusion 11 of the sliding element 3 enters the concave seat 13 and slides therein, thereby closing all air exits 14, such that the air remains trapped in the compression chamber of the cylinder 5, between the piston and the end element 7. As already mentioned, this causes the sliding element to slow down and possibly stop completely before it impacts against the end element 7, or any other element, thereby avoiding shocks or pulse stresses and, as a result, excessive wear and breakdowns.

Both the protrusion 11 of the sliding element 3 and the concave seat 13 of the end element 7 are cylindrical in shape, and one of them 11, 13 has gasket means 19. The length of the portion of the concave seat 13 and/or of the protrusion 11 sliding against the gasket means 19 is at least equal to the maximum predetermined length M of the terminal section of the stroke of the sliding element 3 during which said air trapped in the closed compression chamber 15 becomes compressed.

With respect to the gasket means 19, the air exits 14 are always in a position opposite the piston 4 of the sliding element 3. As such, when both the protrusion and the concave seat are arranged against the gasket means, the compression chamber turns out to be closed and sealed.

The piston of the sliding element 3, the guide element 5, the end element 7, the protrusion 11 and the concave seat 13 are almost cylindrical or discoidal in shape, and are coaxial, the corresponding geometrical axis being parallel to the sliding direction D.

The gasket means 19 consist of a set of ring seals, for example O-ring-type or lip seals, arranged in respective hollow, ring-shaped housings formed in the portion of the concave seat 13 adjacent to the guide element 5 and leading into the same 5. In other words, the housings of the gasket means 19 are formed in the portion of the concave seat 13 entering the protrusion 11.

The air exits 14 lead into a portion of the concave seat 13 spaced from the respective opening in the guide element 5 and from the housings for the gasket means 19. The depth of the concave seat 13 is approximately equal to the longitudinal extension of the protrusion 11. The sliding element 3 bears a stem 23 that slides, in an airtight manner, into a hole formed in the end element 7. Said stem 23 acts as an actuation rod for the ejection of nails or staples by transmitting motion from the sliding element to said nails or staples.

A middle portion of the cylinder wall of the guide element 5 bears at least a pressure relief valve 25, preferably a set of valves 25 comprising through-holes arranged on a circumference of the cylinder wall, whose outer ends are closed by a common elastic ring-shaped element.

It is important to note that by providing appropriate dimensions for the concave seat 13, the protrusion 11 and the parts related thereto, it is possible to determine both the course of the braking force and the stroke during which said braking force acts on the sliding element 3.

Claims

1) Nailer, stapler or similar device with shock absorber comprising at least one sliding element (3), constrained to slide in a sliding direction (D) by a guide element (5) between two initial (I) and final (F) conditions, and an end element (7) fixed adjacent to the position taken by the sliding element (3) in its final condition (F); said device (1) being characterized in that the sliding element (3) comprises a protrusion (11) turned towards the end element (7) which comprises a concave seat (13) which is of a complementary shape to that of the protrusion (11) and which has exits (14) for the air trapped between the sliding element (3) and said protrusion (11) which is housed, slidingly and pneumatically, in such concave seat

(13) at least in the terminal section, of maximum predetermined length (M), of the stroke of the sliding element (3) towards the final condition (F), where in correspondence with such terminal section the sliding element (3) closes the exits

(14) and, together to the end element (7) and to a portion of the guide element (5) delimits, with pneumatic seal, a compression chamber (15) whose internal volume decreases as the sliding element (3) approaches the final condition (F) causing an increase in pressure which acts on the sliding element (3) reducing its speed and/or stopping it.

2) Device according to claim 1 characterized in that the guide element (5) consists of a cylinder of the pneumatic type, the sliding element (3) comprises a piston (4) sliding, with pneumatic seal, inside the cylinder and the end element (7) is sealed to the end of the cylinder corresponding to the final condition (F).

3) Device according to claim 1 or 2 characterized in that the protrusion (11) of the sliding element (3) and the concave seat (13) of the end element (7) are cylindrical and one of them (11, 13) has gasket means (19) where the length of the portion of the concave seat (13) or of the protrusion (11) which slides against the gasket means (19) is at least equal to the maximum predetermined length (M) of the terminal section of the sliding of the sliding element (3).

4) Device according to claims 2 and 3 characterized in that the air outlets (14) are always in the opposite position to the piston of the sliding element (3) with respect to the gasket means (19).

5) Device according to the preceding claims characterized in that the piston (4) of the sliding element (3), the guide element (5), the end element (7), the protrusion (11) and the concave seat (13) are almost cylindrical or discoidal in shape and are coaxial where the corresponding geometric axis is parallel to the sliding direction (D).

6) Device according to any one of claims 2-5 characterized in that the gasket means (19) consist of a set of ring seals placed in respective ring housings formed in the portion of the concave seat (13) adjacent to the guide element (5) and which flows into it (5).

7) Device according to claim 6 characterized in that the air outlets (14) flow into a portion of the concave seat (13) spaced from the respective opening in the guide element (5) and from the housings for the gasket means (19); where the depth of the concave seat (13) is approximately equal to the longitudinal extension of the protrusion (11).

8) Device according to any one of the preceding claims characterized in that the sliding element (3) carries a stem (23) sliding, pneumatically sealed, in a hole formed in the end element (7) and acts as an actuation rod for the ejection of nails or staples.

9) Device according to claim 2 or according to claim 2 and any one of claims 3-8 characterized in that the cylinder of the guide element (5) has on its wall at least one overpressure valve (25).

10) Device according to claim 2 or according to claim 2 and any one of claims 3-9 characterized in that the end of the cylinder of the guide element (5) opposite the end element (7) has a cylinder closure head (27) carrying a compressed air inlet valve (29) for operating the sliding piston of the sliding element (3).