Machining apparatus

Abstract

A machining apparatus includes: a rotating shaft rotatably supported by a housing; a rotary tool detachably attached to the rotating shaft; an attachment; and a bracket. The rotary tool includes a front end surface facing in a first direction lying along an axial direction of the rotating shaft, and a rear end surface facing in a second direction opposite to the first direction. The attachment is detachably connected to the front end surface of the rotary tool. The bracket rotatably supports the attachment in a state of being supported by the housing.

1 . A machining apparatus comprising:
 a rotating shaft rotatably supported by a housing; and   a rotary tool having a cylindrical shape and detachably attached to the rotating shaft,   wherein the rotating shaft includes a protruding end portion protruding from the housing in a first direction lying along an axial direction of the rotating shaft, the rotary tool being attached to the protruding end portion, and   the rotary tool includes a front end surface formed at an end portion of the rotary tool in the first direction and facing in the first direction, and a rear end surface formed at an end portion of the rotary tool in a second direction and facing in the second direction, the second direction being opposite to the first direction,   the machining apparatus further comprising:   an attachment detachably connected to the front end surface of the rotary tool; and   a bracket supported by the housing and configured to rotatably support the attachment.   
     
     
         2 . The machining apparatus according to  claim 1 , wherein
 the rotating shaft and the rotary tool are coupled by a first coupling member,   the rotary tool and the attachment are coupled by a second coupling member, and   the second coupling member is disposed outward of the first coupling member in a radial direction of the rotary tool.   
     
     
         3 . The machining apparatus according to  claim 1 , wherein
 the attachment includes an auxiliary rotating shaft member extending in the first direction and aligned with the rotating shaft, and   the bracket includes an insertion hole into which the auxiliary rotating shaft member is inserted, and a bearing interposed between a side surface of the auxiliary rotating shaft member and an inner surface of the insertion hole.   
     
     
         4 . The machining apparatus according to  claim 3 , further comprising a first seal member and a second seal member, wherein
 the bearing is interposed between the first seal member and the second seal member in the axial direction.   
     
     
         5 . The machining apparatus according to  claim 3 , further comprising a clamp configured to tighten the bearing from both the first direction and the second direction. 
     
     
         6 . The machining apparatus according to  claim 5 , wherein
 the clamp includes a nut, a first spacer, and a second spacer, the bearing being interposed between the first spacer and the second spacer in the axial direction,   the auxiliary rotating shaft member includes a threaded portion on the side surface of the auxiliary rotating shaft member, and   the first spacer and the second spacer tighten the bearing as the nut is screwed onto the threaded portion.   
     
     
         7 . The machining apparatus according to  claim 3 , wherein
 the bearing is a cylindrical roller bearing.   
     
     
         8 . The machining apparatus according to  claim 1 , wherein
 the rotary tool is a grinding wheel, and the machining apparatus is a grinding apparatus.   
     
     
         9 . The machining apparatus according to  claim 8 , wherein
 the grinding wheel includes a substrate made of a metallic material, and abrasive grains fixed to an outer surface of the substrate.   
     
     
         10 . The machining apparatus according to  claim 8 , wherein
 the grinding wheel includes a grinding part having a helical shape and formed on an outer circumferential surface of the grinding wheel that is located between the front end surface and the rear end surface, and   the grinding part grinds a toothed portion of a gear.