Honing machine

Claim 2

A honing machine comprising a honing stone supported for rotation with a rotary shaft, means for rotating said honing stone, advance means for feeding said honing stone radially outwardly of said rotary shaft, and said advance means including a combination of a constant pressure advance mechanism and a constant speed advance mechanism and selecting means for automatically selecting one of said two mechanisms which is faster in advance speed than the other for feeding the honing stone.

Claim 3

A honing machine as claimed in claim 1, wherein said advance means further includes a feed member for feeding said honing stone radially outwardly of said rotary shaft, said constant pressure advance mechanism includes fluid cylinder means for transmitting a constant pressure driving force to said feed member, said constant speed advance mechanism includes mechanical driving means for transmitting a constant speed driving force to said feed member, and said selecting means includes connecting means for transmitting said constant speed driving force from said mechanical driving means only toward said feed member.

Claim 4

A honing machine as claimed in claim 2, wherein said fluid cylinder means has a piston rod which is operatively connected with said feed member, said mechanical driving means has a driven member rotationally driven at a constant speed and said connecting means operatively connects said driven member with the piston rod of said fluid cylinder means and includes a one-way clutch for transmitting the driving force from said driven member only towards said piston rod.

Claim 5

A honing machine according to claim 1, wherein said constant pressure advance mechanism consists of fluid cylinder means and said fluid cylinder means is provided with returning fluid cylinder means for returning said fluid cylinder means a predetermined amount by withdrawing a predetermined volume of pressurized fluid from the pressure side thereof.

Claim 6

A honing machine as claimed in claim 2, wherein said advance mechanism further includes a first rack member operatively connected with said feed member, a pinion meshing with said first rack member, and a second rack member meshing with said pinion, said fluid cylinder means is connected with said second rack member, said mechanical driving means has a driven member rotationally driven at a constant speed and said connecting means includes a one-way clutch for transmitting the rotational force of said driven member to said pinion.

Claim 7

A honing machine according to claim 5, wherein frictional means is provided which contacts said driven member with a frictional force larger than that of said one-way clutch when said one-way clutch is making an idling rotation.

Claim 8

A honing machine as claimed in claim 1, wherein said advance means comprises a feed member for feeding said honing stone radially outwardly of said rotary shaft, an axially movable shaft operatively connected with said feed member for effecting feeding operation of the feed member when axially moved, and said constant pressure advance mechanism comprises fluid operated piston-cylinder means having a cylinder and a piston received by said cylinder for reciprocating movement therein, one of the cylinder and the piston being movable as a unit with said axially movable shaft and the other being combined with said constant speed advance mechanism and means for supplying a constant fluid pressure to said cylinder for driving said axially movable shaft to operate the feed member.

Claim 9

A honing machine as claimed in claim 1, wherein said advance means comprises a feed member for feeding said hOning stone radially outwardly of said rotary shaft, a driving member operatively connected with said feed member, said constant pressure advance mechanism including fluid cylinder means having a piston connected with said driving member, said constant speed advance mechanism including a female screw member rotationally driven at a constant speed, a male screw member meshing with said female screw member, means for unrotatably and axially movably supporting said male screw member, a driven member supported on said male screw member in such a manner as to be movable together with said male screw member and means for holding said driven member constantly in contact with the free end of said driving member, said driving member being operated by said fluid cylinder means or said male screw member whichever is faster in operating speed thereby to feed the honing stone radially outwardly of the rotary shaft through said feed member.