Tool holder

Abstract

In a tool holder, when oil supplied via an oil supply passage and an oil introducing passage reaches an atomizing space, the oil is atomized by an air flow of carrier gas consisting of compressed air, and then water supplied from a water supply passage and a water introducing passage is formed into a water drop in the atomizing space by an air flow of oil containing compressed air to generate the water drop with oil film in which the oil film is formed on a surface of the water drop. Since the water drop with oil film is supplied to a work piece through a top nozzle and an in-tool passage, the water drop with oil film is generated at an extremely close location to a tool, and therefore, responsiveness when supplying the water drop with oil film to the work piece can be enhanced.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a side view of a spindle part of a machine tool on which a tool holder according to an embodiment is mounted;

FIG. 2 is a sectional view showing the inside of the tool holder according to the embodiment;

FIGS. 3A and 3B are a front view (FIG. 3A) and a sectional view (FIG. 3B) of a mist generating nozzle;

FIG. 4 is a schematic diagram of a supply system according to the embodiment;

FIG. 5 is a sectional view showing the inside of a tool holder according to another embodiment;

FIG. 6 is a schematic view showing the structure of a conventional tool holder; and

FIG. 7 is a conceptual view of water drops with oil films and a surface of a work piece to which the water drops with oil films is attached.

Claims

1. A tool holder which is mounted on a machine tool for holding a tool for machining a work piece, comprising: a tool mounting part connected to a spindle of the machine tool, the tool being mounted on the tool mounting part; anda support part fixed to a body side of the machine tool, the support part supporting the tool mounting part via a bearing so that the tool mounting part is rotatable, whereinthe tool mounting part contains in its inside: a mist generating nozzle formed in a cylindrical shape in which an atomizing space is formed in its center so as to be opened forward, and in which an oil introducing passage communicating with a rear side portion of the atomizing space and a water introducing passage communicating with a front side portion of the atomizing space are formed; and a top nozzle disposed in a front side portion of the mist generating nozzle to abut on a rear end portion of the tool so as to communicate with an in-tool passage formed inside the tool,an oil supply passage which supplies oil to the oil introducing passage by carrier gas consisting of compressed air, and a water supply passage which supplies water to the water introducing passage are formed in the support part, andwhen the oil supplied via the oil supply passage and the oil introducing passage reaches the atomizing space, the oil is atomized by an air flow of the carrier gas consisting of the compressed air, the water supplied from the water supply passage and the water introducing passage is formed into a water drop in the atomizing space by an air flow of oil containing compressed air containing said atomized oil so as to generate a water drop with oil film in which the oil film is formed on a surface of the water drop, and the water drop with oil film is supplied to the work piece through the top nozzle and the in-tool passage.

2. The tool holder according to claim 1, wherein incident angles of the oil introducing passage and the water introducing passage with respect to the atomizing space in the mist generating nozzle are formed to be an acute angle.

3. The tool holder according to claim 1, wherein the atomizing space in the mist generating nozzle is formed to pass through up to a rear end surface of the mist generating nozzle, an air introducing passage is formed in the tool mounting part to communicate with the atomizing space passing through up to the rear end surface, andthe atomization of the oil and the generation of the water drop with oil film in the atomizing space are promoted by supplying compressed air to the air introducing passage from the outside.

4. The tool holder according to claim 2, wherein the atomizing space in the mist generating nozzle is formed to pass through up to a rear end surface of the mist generating nozzle, an air introducing passage is formed in the tool mounting part to communicate with the atomizing space passing through up to the rear end surface, andthe atomization of the oil and the generation of the water drop with oil film in the atomizing space are promoted by supplying compressed air to the air introducing passage from the outside.