The present invention relates to a tool holder device.

More in detail, the invention relates to a tool holder device, of the quick-connect type, comprising at least one interchangeable head, and having a structure such as to facilitate accurate and stable housing of the head inside it.

Nowadays, there are different types of tool holder devices that are used to realize modular machining systems, allowing different types of heads to be mounted on the same holder.

One of the main problems with standard tool holders in use to date is inherent in the fact that the head and stem are made in a single body, not allowing for interchangeability of the head.

Known quick-change tool holders often comprise an interface between the head and the tool holder that does not allow for maintaining, high repeatability, rigid and precise contact between the parts, regardless of the type of head to be mounted on the tool holder.

Current tool holders require, especially for mounting and dismounting parts, high external stress, which makes the system unwieldy for the user. This results from both the geometry of the attachment and housing between the head and device as well as the presence of fastening means between the parts.

Based on the above, nowadays, there is no tool holder device designed in such a way as to simultaneously meet all the above requirements.

Therefore, the aim of the present invention is to overcome the aforementioned drawbacks and, in particular, to realize a tool holder device that allows for a precise and stable interface with the relevant interchangeable head. Another aim of the present invention is to realize a tool holder device that allows high repeatability in the attachment of different heads, depending on the requirements given by machining.

In addition, it is aim of the present invention to realize a tool holder device that is easy for the user to handle, ensuring an effortless release of the interchangeable head.

These and other aims are achieved by realizing a tool holder device, according to the attached claim 1 ; other detailed technical features of the tool holder device, according to the present invention, are set forth in the dependent claims.

Further features and advantages of the tool holder device, which is the object of the present invention, will be more apparent from the following description.

It should be noted that this description relates to an illustrative and preferred, but not limiting, form of embodiment of the tool holder device, with reference to the attached drawings, in which:

- figure 1 shows a perspective view of the tool holder device according to the present invention;

- figure 2A is a front view relating to the detail of the connection point or interface between the stem of the device objected to in the present invention and the interchangeable head, in particular view from the stem side;

- figure 2B shows a front view related to the detail of the connection point or interface between the stem of the device object of the present invention and the head, in particular, viewed from the side of the head;

- figure 3A shows a frontal and schematic view of the connection point or interface in figure 2A, from the stem side;

- -figure 3B shows a front and schematic view of the attachment point of figure 2B, from the side of the head;

- -figure 4A shows a schematic and side view of the figure 1 tool holder device, particularly the stem, without the head;

- -figure 4B shows an additional side view in longitudinal section of the figure 1 tool holder device, particularly of the stem, without the head;

- -figure 5 shows an additional perspective view of the figure 1 device, in which the detail of the connection between the stem and the head is visible, according to the present invention; - -figure 6A is a perspective view of the interchangeable head belonging to the device, according to the present invention;

- -figure 6B shows a longitudinal sectional view of the interchangeable head in figure 6A, according to the present invention.

With reference to the above mentioned figures, 10 generically denotes a tool holder device according to the present invention. In particular, said tool holder device comprises a stem 11 and at least one interchangeable head 12, such as to be connected to said stem 11 , forming the tool holder device 10, object of the present invention.

Advantageously, such a stem 11 could possess any geometry, but, as visible in the figures, in one preferred embodiment it possesses a polyhedral geometry, in particular, of a parallelepiped. Similarly to the stem 11 , the interchangeable head 12 may also take any shape and may comprise any type of tool, depending on the machining to be performed.

Also advantageously, said stem 11 comprises a junction seat 111 at the side of engagement with the interchangeable head 12. In other words, said junction seat 111 is placed by a first side 112 of stem 11 , which is facing outside stem 11 in the direction of said head 12.

In particular, said junction seat 111 has a preferably trilobo-conical shape of the concave type to allow for quick connection between the parts of the device 10 and to precisely define the positioning of the head 12 within the stem 11 , as will be better explained in the following.

Advantageously, as seen particularly in figures 2A and 2B, the trilobo- conical shape from the junction seat 111 , particularly because of its conical and concave geometry, is such that it extends longitudinally within stem 11 , increasing the rigidity of the engagement between stem 11 and head 12.

Additionally, this type of engagement is of the universal type, so that stem 11 can be engaged with different types of heads 12, as opposed to the current standard type, as described above in the prior art.

In detail, with particular reference to figures 2B, 6A and 6B, the head 12 in turn comprises a second junction seat 121 of trilobo-conical shape of the convex type, thus substantially complementary to the junction seat 111 of the stem 11 , with which it will engage for forming the device 10, according to the present invention.

Advantageously, at a lateral portion of the stem 11 , at a second side 113, perpendicular to the first side 112 thereof, there are two screws for locking and unlocking the head 12 within the junction seat 111 , in the conical portion thereof, of the stem 11.

In addition, in preferred embodiment forms, as visible in longitudinal section in figure 4B, these screws are orthogonal to the conical portion of junction seat 111 and, in particular, to the second junction seat 121 of head 12.

In more detail, as visible in figures 1 , 4A and 4B, these two screws are: a first locking screw 20, and a second unlocking screw 21 , adjacent to the aforementioned first screw 20.

In preferred but not limiting embodiment forms, the said first screw 20 is placed substantially at the edge that is structurally created between the second side 113 and the first side 112. The second screw 21 , being adjacent to the first screw 20, is also placed on the second side 113 but on the opposite side of the edge from the first screw 20.

Advantageously, the first screw 20 is such that it locks the second convex conical junction seat 121 of the head 12 inside the first concave conical junction seat 111 of the stem 11 , in particular, as visible in figure 6A, this screw is such that it fits inside an invitation 122 at the head 12.

Again advantageously, the second unlocking screw 21 is contacting and acting on a chamfer 123 located on head 12. The actuation of the second unlocking screw 21 allows the head 12 to be pulled out of the first conical junction seat 111 , after previously loosening the locking screw 20.

In particular, advantageously, such second screw 21 allows the two parts (stem 11 and head 12) to be released by internal push on the parts without any effort on the part of the user.

It has thus been found that the solution which is the object of the present invention enables the intended aims to be achieved; from the description made it is clear, therefore, that the characteristics of the tool holder device, which is the object of the present invention, are clear, as are its advantages.

Finally, it is clear that numerous variations can be made to the tool holder device under consideration, without departing from the principles of novelty inherent in the inventive idea which is the object of the attached claims, just as it is clear that, in the practical implementation of the invention, the materials, shapes and sizes of the details illustrated may be any as required and the same may be replaced with others which are technically equivalent.