Machining apparatus and machining method

Abstract

A machining apparatus (100) is provided with: high-pressure water piping (10) that is capable of supplying high-pressure water (WH); abrasive grain piping (20) that is capable of supplying abrasive grains (AB); a spraying part (30) having a high-pressure water introduction part by which the high-pressure water (WH) is introduced, an abrasive grain introduction part by which the abrasive grains (AB) are introduced, a mixing part that mixes the high-pressure water (WH) and the abrasive grains (AB), and a nozzle that sprays the high-pressure water (WH) with which the abrasive grains (AB) have been mixed onto an object to be machined (OBJ); and a detection part (40) that measures the pressure (PM) inside the abrasive grain piping (20) and detects when the pressure (PM) is less than a lower-limit threshold value.

1 . A machining apparatus comprising:
 a high-pressure water pipe through which high-pressure water is supplied;
 an abrasive grain pipe through which abrasive grains are supplied; 
 an injection unit which includes a high-pressure water introduction portion into which the high-pressure water is introduced, an abrasive grain introduction portion into which the abrasive grains are introduced, a mixing portion in which the high-pressure water and the abrasive grains are mixed with each other, and a nozzle which injects the high-pressure water having the mixed abrasive grains to an object to be machined; and 
 a detection unit which measures a pressure inside the abrasive grain pipe and detects that the pressure is lower than a lower threshold value. 
   
     
     
         2 . The machining apparatus according to  claim 1 ,
 wherein the detection unit further detects that the pressure is higher than an upper threshold value.   
     
     
         3 . The machining apparatus according to  claim 1 ,
 wherein the detection unit specifies that an abnormality is present on an upstream side of a pressure measurement location by the detection unit in a case where the pressure is lower than the lower threshold value.   
     
     
         4 . The machining apparatus according to  claim 1 , further comprising:
 a partition pipe which separates a first space extending in one direction from the high-pressure water introduction portion to the nozzle and a second space around the first space from each other, inside the mixing portion and includes an opening on an introduction straight line extending in an introduction direction of the abrasive grains from the abrasive grain introduction portion; and
 an exhaust portion which is provided at a position facing the abrasive grain introduction portion across the first space and exhausts air inside the second space. 
   
     
     
         5 . A machining apparatus comprising:
 a high-pressure water pipe through which high-pressure water is supplied;
 an abrasive grain pipe through which abrasive grains are supplied; 
 an injection unit which includes a high-pressure water introduction portion into which the high-pressure water is introduced, an abrasive grain introduction portion into which the abrasive grains are introduced, a mixing portion in which the high-pressure water and the abrasive grains are mixed with each other, and a nozzle which injects the high-pressure water having the mixed abrasive grains to an object to be machined; and 
 a partition pipe which separates a first space extending in one direction from the high-pressure water introduction portion to the nozzle and a second space around the first space from each other, inside the mixing portion and includes an opening on an introduction straight line extending in an introduction direction of the abrasive grains from the abrasive grain introduction portion; and 
 an exhaust portion which is provided at a position facing the abrasive grain introduction portion across the first space and exhausts air inside the second space. 
   
     
     
         6 . A machining method comprising:
 a step of measuring a pressure inside an abrasive grain pipe of a machining apparatus including a high-pressure water pipe through which high-pressure water is supplied, an abrasive grain pipe through which abrasive grains are supplied, and a nozzle which is connected to the high-pressure water pipe and the abrasive grain pipe and injects the high-pressure water mixed with the abrasive grains to an object to be machined; and
 a step of detecting that the pressure is lower than a lower threshold value.