D E S C R I P T I O N

"Portable cutting tool"

Technical field of the invention

The present invention relates to a portable cutting tool, such as a harvester, strimmer or lawnmower, and preferably a hedge cutter.

Background of the invention Most research and developments in the technical sector of portable cutting tools has been aimed at improving elements such as the handgrips or handles of tools, the mechanisms that transmit the rotating movement of a motor to the reciprocating movement of the tool's multiple blades, the user protection elements and many other characteristics of said tools. In any case, there is currently no system to help improve the continuous running of the machine without the need for the manual oiling process that is normally carried out on this type of tools.

As is known, portable cutting tools generally comprise at least two sets of multiple blades that move with a reciprocating motion in relation to one another in a longitudinal direction. Due to the way they are arranged, these sets of multiple blades undergo a great high degree of wear and tear due to the friction between the two sets of blades, so they are usually made from steel in order to prolong their duration, as it is particularly resistant. In the case of e.g. a hedge cutter, as well as being subjected to said friction, the blades also become impregnated with resin, which must normally be removed manually with the aid of a lubricant or oil that in turn reduces the friction between the two blades.

Another drawback with this type of tools is the fact that the blades need to be sharpened relatively often, for the aforementioned reasons.

At present this type of tools, as well as requiring a certain amount of maintenance, involve the user oiling the blades on a regular basis, as can be observed in Fig. 1.

It can therefore be seen that there is a need for a portable cutting tool that is capable of overcoming said drawbacks presented by the portable cutting tools currently known.

Explanation of the invention

The portable cutting tool that is the object of the present invention comprises at least two sets of multiple blades that move with a reciprocating motion in relation to one another in a longitudinal direction, in a known manner. Essentially, the tool is characterised in that it is provided with a built-in oiling system with at least one tank containing a lubricant and a distribution pipe for said oil, positioned adjacent to said blades in a longitudinal direction.

According to another characteristic of the invention, the tool comprises a pump that propels the lubricant, which could be e.g. oil or other lubricant substance to reduce friction, from the tank to the distribution pipe.

According to another characteristic of the invention, the pump can be automatic and it is controlled by a cam actuated by the movement of the tool's blades.

Another characteristic of the tool of the invention consists of the distribution pipe having at least one pair of holes longitudinally distributed along the length of said pipe, the diameter of which is larger the further away they are from the pump.

According to another characteristic of the invention, between the tank and the pump there is a valve to let the lubricant pass.

Brief description of the drawings

The attached drawings show a non-limiting example of an embodiment of the tool that is the object of the present invention, in order to aid a better understanding thereof. In said drawings:

Fig. 1 shows a schematic view of the usual method of oiling in the state of the art;

Fig. 2 shows a schematic perspective view of the tool of the invention;

Fig. 3 is also a schematic perspective view of part A of the tool of the invention; and

Fig. 4 is a diagram of the oiling system of the tool of the invention.

Detailed description of the drawings

As can be seen in the attached drawings, the portable cutting tool 1 that is the object of the invention comprises, in a known manner, two sets 2 of multiple blades 2a, which move with a reciprocating motion in relation to one another in a longitudinal direction.

The portable cutting tool 1 shown in Fig. 2 corresponds specifically to a

hedge cutter that, like conventional hedge cutters, consists of a casing 7 with a first handle 7a with a press button 7b electric on/off switch, not shown, and a second handle 7c from which two sets 2 of multiple blades 2a project.

Characteristically, in Fig. 2 it can be seen that the hedge cutter comprises an oiling system 3 with a tank 31 for a lubricant and a distribution pipe 32 of said oil positioned adjacent to said blades 2a in a longitudinal direction (part A of Fig. 2, which can observed in more detail in Fig. 3). Advantageously, this tool avoids the need to perform the usual manual oiling task that is carried out on tools in the prior art, as shown in Fig. 1. As is shown in Fig. 4, the hedge cutter comprises a pump 33 that propels the lubricant 31a, such as an oil to reduce friction, from the tank 31 to the distribution pipe 32. The pump 33 is automatic and its piston 35 is actuated by a cam 36, actuated by the alternate reciprocating movement of the blades 2 of the tool 1. In another variant that is not shown here, there is a valve 34 between the tank 31 and the pump 33 to let the lubricant 31a pass, which is adapted to limit or interrupt the flow of the lubricant 31 as the user wishes. It should be mentioned that the pump 33 can be actuated manually.

As exemplified in part A of the hedge cutter with more detail in Fig. 3, the distribution pipe 32 is provided with four holes 5 longitudinally distributed along the length of said pipe 32. These holes 5 are disposed on a part of the longitudinal surface of said pipe 32 close to the blades 2a. Furthermore, to facilitate the regular removal of the lubricating oil along said pipe 32, the diameter of said holes 5 increases the further away they are from the pump 33, i.e. the smallest of the holes 5 is the closest to the tank 31 of the tool 1 , whilst the largest is the one that is furthest away. Other possibilities that are not shown here also contemplate that the tool 1 could comprise more than one pipe 32.

In another variant, which is not shown here, it is contemplated that the piston 35 of the pump 33 of the tool 1 could be actuated by a cam 33 that is actuated by the movement of the connection rods that bring about the alternate reciprocating movement of the blades 2 of the tool 1.

A tool 1 like that described herein can be homogeneously and constantly oiled, being especially applicable to portable cutting tools such as hedge cutters. It should be mentioned that, having sufficiently described the nature of the present invention and the way in which it is put into practice, it is stated that anything that does not alter, change or modify its fundamental principle is subject to variations regarding details.