Honing Method and Honing Tool

Abstract

In a honing method for machining the internal surface of a bore in a workpiece with the aid of at least one honing operation, during a honing operation, an expandable honing tool is moved up and down within the bore in order to produce a reciprocating movement in the axial direction of the bore and at the same time is rotated in order to produce a rotational movement combined with the reciprocating movement. In the process, a bottle-shaped bore is produced, said bore having, following a bore inlet, a first bore section with a first diameter, a second bore section with a second diameter, which is larger than the first diameter, away from the bore inlet, and a transition section with a continuous transition from the first to the second diameter between the first and the second bore section. During at least one honing operation, use is made here of an annular tool ( 200 ) which has at least one annular cutting group ( 220 ) having a plurality of radially infeedable cutting material bodies which are distributed around the circumference of a tool body and are designed as honing segments which are wide in the circumferential direction and are narrow in the axial direction, wherein an axial length of the honing segments, as measured in the axial direction, is smaller than the width measured in the circumferential direction, and the axial length of the cutting region equipped with cutting material bodies is smaller than the effective outside diameter of the honing tool. The method is particularly suitable for honing cylinder faces during the production of cylinder blocks or cylinder liners for reciprocating piston engines.

1 . A honing method for machining the internal surface of a bore in a workpiece with the aid of at least one honing operation, in particular for honing cylinder faces during the production of cylinder blocks or cylinder liners for reciprocating piston engines,
 wherein, during a honing operation, an expandable honing tool is moved up and down within the bore in order to produce a reciprocating movement in the axial direction of the bore and at the same time is rotated in order to produce a rotational movement combined with the reciprocating movement,   wherein a bottle-shaped bore is produced, said bore having, following a bore inlet, a first bore section with a first diameter, a second bore section with a second diameter, which is larger than the first diameter, away from the bore inlet, and a transition section with a continuous transition from the first to the second diameter between the first and the second bore section,   wherein, during at least one honing operation, use is made of an annular tool which has at least one annular cutting group having a plurality of radially infeedable cutting material bodies which are distributed about the circumference of a tool body and are designed as honing segments which are wide in the circumferential direction and are narrow in the axial direction,   wherein an axial length of the honing segments, as measured in the axial direction, is smaller than the width measured in the circumferential direction, and the axial length of the cutting region equipped with cutting material bodies is smaller than the effective outside diameter of the honing tool.   
     
     
         2 . The honing method as claimed in  claim 1 , wherein first of all a bore having a circular-cylindrical bore shape is produced and then, in a bottle honing operation, a bottle-shaped bore shape is produced by honing with axially varying honing removal. 
     
     
         3 . The honing method as claimed in  claim 2 , wherein, during the bottle honing operation, use is made of an expandable honing tool having at least one annular cutting group, wherein honing segments of the cutting group are infed radially during a downward stroke in accordance with the bottle shape depending on the stroke position and are radially retracted during an upward stroke in accordance with the bottle shape depending on the stroke position. 
     
     
         4 . The honing method as claimed in  claim 2 , wherein, during the bottle honing operation, use is made of an expandable honing tool with honing sticks, the length of which is more than 50% of the length of the bore, wherein, in a first phase, the honing tool is moved up and down between an upper and a lower reversing point in a first stroke position, then, in a second phase, the upper reversing point is changed incrementally in the direction of the lower reversing point, and therefore the stroke position is shifted in the direction of a second stroke position in the region of the second bore section, and then, in a third phase, the honing tool is moved up and down in the second stroke position. 
     
     
         5 . The honing method as claimed in  claim 4 , wherein, after the bottle honing operation, a smoothing honing operation for smoothing the bore profile in the transition region is carried out, wherein, during the smoothing honing operation, use is made of an expandable honing tool having at least one annular cutting group. 
     
     
         6 . A honing tool, in particular for carrying out the honing method as claimed in  claim 1 , with a tool body which defines a tool axis, at least one cutting group which is attached to the tool body and has cutting material bodies for the material-removing machining of the internal surface of a bore, and a cutting-group infeed system, assigned to the cutting group, for exerting an infeed force, acting radially with respect to the tool axis, on the cutting material bodies of the cutting group,
 wherein the honing tool is designed as an annular tool and has at least one annular cutting group having three or more radially infeedable cutting material bodies which are distributed around the circumference of the tool body and are designed as honing segments which are wide in the circumferential direction and are narrow in the axial direction, wherein an axial length (LHS) of the honing segments, as measured in the axial direction, is smaller than the width measured in the circumferential direction, and the axial length of the cutting region equipped with cutting material bodies is smaller than the effective outside diameter of the honing tool.   
     
     
         7 . The honing tool as claimed in  claim 6 , wherein the axial length of the honing segments is less than 30% of the effective outside diameter of the honing tool, and/or the axial length of the honing segments lies within the range of 5 mm to 20 mm, and/or the axial length of the honing segments is less than 10% of the bore length of the bore to be honed. 
     
     
         8 . The honing tool as claimed in  claim 6 , wherein more than half of the circumference of an annular cutting group is occupied with cutting material bodies. 
     
     
         9 . The honing tool as claimed in  claim 6 , wherein a cutting group is composed of three, four, five or six honing segments. 
     
     
         10 . The honing tool as claimed in  claim 6 , wherein the cutting group is arranged in the vicinity of a spindle-remote end of the tool body in such a manner that the cutting group is located exclusively in the spindle-remote half of the tool body. 
     
     
         11 . The honing tool as claimed in  claim 6 , wherein the annular tool has a single annular cutting group which is arranged at a free end of the tool body. 
     
     
         12 . The honing tool as claimed in  claim 6 , wherein an annular cutting group has two groups of honing segments which are infeedable independently of each other, wherein honing segments of the groups are arranged in an alternating manner in the circumferential direction. 
     
     
         13 . The honing tool as claimed in  claim 6 , wherein the annular tool has a first annular cutting group and at least one second annular cutting group which is arranged axially offset with respect to the first annular cutting group and is infeedable independently of the first annular cutting group. 
     
     
         14 . The honing tool as claimed in  claim 6 , wherein one or more sensors of a diameter measuring system are arranged on the honing tool, wherein measuring nozzles of a pneumatic diameter measuring system are in each case attached to the tool body. 
     
     
         15 . The honing tool as claimed in  claim 6 , wherein an integrated, multiaxially movable joint is provided on the tool body. 
     
     
         16 . The honing method as claimed in  claim 5 , wherein, during the smoothing honing operation, the cutting material bodies are pressed at a constant infeed force on to the internal surface of the bore. 
     
     
         17 . The honing tool as claimed in  claim 7 , wherein the axial length of the honing segments is between 10% and 20% of said outside diameter. 
     
     
         18 . The honing tool as claimed in  claim 8 , wherein more than 70% of the circumference of an annular cutting group is occupied with cutting material bodies. 
     
     
         19 . The honing tool as claimed in  claim 13 , wherein the annular tool has precisely two annular cutting groups. 
     
     
         20 . The honing tool as claimed in  claim 14 , wherein the measuring nozzles of a pneumatic diameter measuring system are in each case attached to the tool body between adjacent honing segments. 
     
     
         21 . The honing tool as claimed in  claim 15 , wherein the integrated, multiaxially moveable joint is a ball and socket joint.