1. Field of the Invention
The present invention relates to the field of tool holders, and more particularly to a tool holder that accommodates a variety of cutting inserts held in position by a variety of clamping mechanisms.
2. Description of the Related Art
The prior art includes a variety of diverse tool holders. For example, The AISI tool holder mechanisms utilize a conical bore whose axis is offset from the insert threaded section. This conical bore tilt the locking pin into abutment with the cutting insert into a central bore. This threaded bore also clamps a screw to screw down the shim seat when the locking pin is not used.
These prior art tool holder constructions are adequate for the purpose and function for which they are specifically designed. However, they are uniformly deficient with respect to their failure to provide a simple, efficient and practical tool holder that accommodates a variety of cutting inserts.
As a consequence of the foregoing situation, there have existed a longstanding need for a new and improved tool holder and the provision of such a construction is a stated objective of the present invention.
The present invention presents a tool holder which utilizes cutting inserts with or without a central bore, allowing the use of several clamping mechanisms using only one insert pocket formed at a forward end thereof. Such new tool holder type permits the use of special clamping mechanisms for ceramic inserts without a central bore, and also the use of clamping mechanisms having a protuberance on the front for securing cutting inserts with a central bore.
The invention presents a tool holder body for clamping an insert within an insert pocket formed at a forward end thereof and having a bottom and at least one side wall for receiving the insert. The tool holder also includes a clamp pocket disposed on the rear side of the insert pocket which accommodates the use of several clamping mechanisms. Each clamping mechanism includes a nose portion with a downward extending nub having a central axis forming an angle with respect to the plane of the tool holder. The clamping mechanism is secured by a screw and by the protuberances which adapt them to the particular and innovating tool holder's shape. The clamping mechanism includes a top surface, a forward lower face and a rearward lower face, and an aperture formed therethrough. A clamp screw inserted through the aperture of the clamping mechanism is received in the clamp-securing bore of the tool holder body to bring the clamp into pressing engagement with the insert, wherein only the nub of the nose portion of the clamp engages a rearward inside surface of the mounting bore of the insert, and wherein only the forward lower face of the nose portion engages a top surface of the insert when the clamp is brought into pressing engagement with the insert. In one embodiment of the clamping mechanism, a coil spring surrounds the clamp screw and is compressed between the clamp and the tool holder to bias the clamp away from the tool holder. An end of the coil spring extends into the bore. The bore is inclined obliquely with respect to a central axis of the screw such that the end of the spring pushes against a rear portion of a wall of the bore to apply a rearward force to the clamp.
These and other attributes of the invention will become more clear upon a thorough study of the following description of the best mode for carrying out the invention, particularly when reviewed in conjunction with the drawings, wherein:
The invention will now be described more in detail by reference to the enclosed drawings which illustrate a preferred embodiment of the invention.
Referring now to
Referring now to
The main innovation concerning the clamps, is the double front and back alignment, clamps presenting a frontal protrusion only are aimed to hold inserts with a central hole, using the clamp's guide located between the clamp screw and the insert-receiving pocket (11).
The clamp for ceramic inserts (29) (
The tool body also holds the insert with a traditional central pin (33) (
Within the clamp for ceramic inserts (29) (
The insert shim (38) is always the same, it can be sized by the pin (33) within the traditional system (
The screw (42) that sizes the clamps for ceramic inserts (29) and (35) has a double thread; the one right threaded into the tool body (10) and the clamp thread (29) and (35), which is threaded to the left.
The clamp (30) (
The clamp set (30) is complemented by a screw (50) and a spring (51) that allows the clamp (30) to release the insert (41) when the screw (50) is loosened. By assembling the parts (30), (50) and (51), together with the insert (41), the screw (39) and the shim seat (38) on the tool body (10), inside the pocket (11) and the clamp pocket (20), they form the clamping system of
The spring (51) that surrounds the screw (50) presses the inside of the clamp pocket (20) and the low part of the clamp (30) around the hole (46). Thus, by loosening the screw (50), the tip of the clamp (30) goes out of the hole of the insert (41), because the surface of the low part of the clamp (30) and the inside of the hole (46) have a slope that forces it to follow the inclination, by raising firstly the tip then the back of the clamp.
In summary, the invention allows the assembly of the traditional clamping system in their two versions: only with the pin (33), or with the clamp (31) and the pin (33) (
Although only exemplary embodiments of the invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible without materially departing from the novel teachings and advantages of this invention. Accordingly, all said modifications are intended to be included within the scope of this invention as defined in the following claims.