State monitoring device of cutting fluid using odor sensor

1. A state monitoring device of a cutting fluid of a machine tool, the machine tool including a cutting-fluid supplying mechanism circulating and repeatedly supplying the cutting fluid to a region where a workpiece is subjected to cutting, the state monitoring device comprising:

an odor sensor configured to measure and output odor intensity of the cutting fluid;

a fluid-quality deterioration determination unit configured to compare a measured odor intensity value measured and output by the odor sensor with a threshold value set in advance in order to determine fluid-quality deterioration of the cutting fluid caused by impurities mixed in the cutting fluid or corrosion of the cutting fluid;

a cutting-fluid deterioration handling unit configured to carry out a cutting-fluid deterioration handling process in response to a determination result of the fluid-quality deterioration determination unit indicating that the measured odor intensity value is equal to or greater than the threshold value; and

a cover surrounding the odor sensor and having an opening inside a cutting-fluid tank in which the cutting fluid to be monitored is stored,

wherein the cover is configured to cover a part of a surface of the cutting fluid stored in the cutting-fluid tank, and

wherein the odor sensor is arranged in a space defined by the cover and the part of the surface of the cutting fluid to measure the odor intensity of an odor of the cutting fluid in said space.

2. The state monitoring device of the cutting fluid of the machine tool according to claim 1 , wherein

the fluid-quality deterioration determination unit has a threshold-value setting unit configured to calculate and set the threshold value based on

the measured odor intensity value measured by the odor sensor for a first time after replacement of the cutting fluid, and

a threshold-value calculating coefficient set in advance.

3. The state monitoring device according to claim 1 , wherein the threshold value is changed depending on the cutting fluid and cutting conditions to be executed.

4. The state monitoring device according to claim 1 , wherein the cutting-fluid deterioration handling unit is configured to:

output a signal representing that the cutting fluid is deteriorated due to mixing of impurities or corrosion;

inform of detection of deterioration of the cutting fluid on a screen of a display device attached to a machine controlling unit of the machine tool;

stop an operation of the machine tool; and

output and display the quality of the cutting fluid based on the measured odor intensity value measured by the odor sensor.

5. A state monitoring device of a cutting fluid of a machine tool, the machine tool including a cutting-fluid supplying mechanism circulating and repeatedly supplying the cutting fluid to a region where a workpiece is subjected to cutting, the state monitoring device comprising:

an odor sensor configured to measure and output odor intensity of the cutting fluid;

a fluid-quality deterioration determination unit configured to compare a measured odor intensity value measured and output by the odor sensor with a threshold value set in advance in order to determine fluid-quality deterioration of the cutting fluid caused by impurities mixed in the cutting fluid or corrosion of the cutting fluid; and

a cutting-fluid deterioration handling unit configured to carry out a cutting-fluid deterioration handling process in response to a determination result of the fluid-quality deterioration determination unit indicating that the measured odor intensity value is equal to or greater than the threshold value,

wherein the threshold value is set in accordance with a type of the cutting fluid and machining conditions of the machining tool,

wherein the machining conditions include a material of the workpiece and a degree of machining accuracy of the machine tool,

wherein the fluid-quality deterioration determination unit has a threshold-value setting unit configured to calculate and set the threshold value based on

the measured odor intensity value measured by the odor sensor for a first time after replacement of the cutting fluid, and

a threshold-value calculating coefficient set in advance, and

wherein the fluid-quality deterioration determination unit is configured to

read the set threshold-value calculating coefficient A,

calculate the threshold value T by multiplying (i) the measured odor intensity value X measured by the odor sensor at the first time after replacement of the cutting fluid by (ii) the threshold-value calculating coefficient A, as an expression T=A×X, and

set and save the calculated threshold value T in a memory.

6. A state monitoring device of a cutting fluid of a machine tool, the machine tool including a cutting-fluid supplying mechanism circulating and repeatedly supplying the cutting fluid to a region where a workpiece is subjected to cutting, the state monitoring device comprising:

an odor sensor configured to detect a type of odor of the cutting fluid;

a cutting-fluid deterioration handling unit configured to carry out a cutting-fluid deterioration handling process in response to an odor detection signal output from the odor sensor; and

a cover surrounding the odor sensor and having an opening inside a cutting-fluid tank in which the cutting fluid to be monitored is stored,

wherein the cover is configured to cover a part of a surface of the cutting fluid stored in the cutting-fluid tank, and

wherein the odor sensor is arranged in a space defined by the cover and the part of the surface of the cutting fluid to detect the type of the odor of the cutting fluid in said space.