Milling tool and method for producing a rolling bearing cage

Abstract

A milling tool includes a main body and a plurality of cutting inserts with respective cutting edges. The main body has an end face and a barrel-shaped curved lateral face. A first group of the plurality of cutting inserts are fastened on the end face, a second group of the plurality of cutting inserts are fastened on the barrel-shaped curved lateral face, and the respective cutting edges describe a barrel shape. Each one of the plurality of cutting inserts may be designed as an indexable insert.

Claims

1. A milling tool comprising: a main body comprising: a flat end face; and a curved lateral face; a plurality of cutting inserts comprising respective cutting edges, wherein: a first group of the plurality of cutting inserts are fastened on the end face; a second group of the plurality of cutting inserts are fastened on the curved lateral face; and respective surfaces of each of the first group of the plurality of cutting inserts facing the flat end face are arranged at an angle relative to the flat end face.

2. The milling tool of claim 1 wherein each one of the plurality of cutting inserts is designed as an indexable insert.

3. The milling tool of claim 1 wherein each one of the plurality of cutting inserts in the second group of the plurality of cutting inserts is fixed with an unchangeable setting on the curved lateral face.

4. The milling tool of claim 1 further comprising a rotational axis, wherein the flat end face is orthogonal to the rotational axis.

5. The milling tool of claim 1 further comprising a rotational axis, wherein the respective cutting edges of the first group of the plurality of cutting inserts define a plane orthogonal to the rotational axis.

6. The milling tool of claim 5, wherein respective surfaces of each of the first group of the plurality of cutting inserts facing the flat end face are arranged at an angle relative to the flat end face.

7. The milling tool of claim 1 wherein each one of the first group of the plurality of cutting inserts has a parallelogram shape.

8. The milling tool of claim 1 wherein each one of the second group of the plurality of cutting inserts has a parallelogram shape.

9. The milling tool of claim 1 wherein a diameter of the curved lateral face decreases as the curved lateral face approaches the flat end face.

10. A milling tool comprising: a rotational axis; a main body comprising: a flat end face; and a curved lateral face; and a plurality of cutting inserts comprising respective cutting edges, wherein: a first group of the plurality of cutting inserts are fastened on the end face; a second group of the plurality of cutting inserts are fastened on the curved lateral face; the respective cutting edges of the first group of the plurality of cutting inserts define a plane orthogonal to the rotational axis; and respective surfaces of each of the first group of the plurality of cutting inserts facing the flat end face are not coplanar with the flat end face.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following, an exemplary embodiment is explained in more detail by means of a drawing. Here, each in a schematic representation:

(2) FIG. 1 shows a first processing step for the production of a rolling bearing cage designed as a comb-type cage,

(3) FIG. 2 shows a second processing step for producing the rolling bearing cage.

DETAILED DESCRIPTION

(4) A milling tool 1, shown in simplified form in FIG. 1, is designed as a profile milling cutter having an essentially cylindrical, generally barrel-shaped profiled main body 2. Multiple cutting inserts 3, namely indexable inserts, are fastened to the flat end face of the main body 2, designated by 7. Cutting inserts 4 are fastened to the curved lateral face of the main body 2, designated by 8. The shape of the cutting inserts 4 does not necessarily match the shape of the cutting inserts 3. Cutting edges of the end-face cutting inserts 3 are designated by 5; cutting edges of the cutting inserts 4 are designated by 6.

(5) Through the entirety of the cutting edges 6 on the barrel-shaped lateral face 8 and the cutting edges 5 on the end face 7 of the milling tool 1, a barrel shape is described overall which, to a good approximation, corresponds to the barrel shape of rolling elements, i.e., barrel rollers, which are guided into a comb-type cage 16 to be produced for a double row spherical roller bearing.

(6) In the manufacture of the rolling bearing cage 16, that is to say the comb-type cage, a cage blank 9 as illustrated in FIG. 1 is assumed. In a first material-removing machining process, a barrel-shaped receptacle 10 is produced in the cage blank 9 by means of the milling tool 1. The cage blank 9 has a cage ring 11, which is also present in the later comb-type cage 16 in largely unchanged form. Individual webs 12 are formed to extend from the cage ring 11 in the axial direction between which barrel-shaped receiving openings 10, that is to say the later rolling element pockets.

(7) Already in the first material-removing machining process, a pocket bottom, designated 13, of the barrel-shaped receptacle 10 is machined to the finished size thereof. The curved walls of the barrel-shaped receptacle 10, on the other hand, are initially produced by the milling tool 1 with an allowance of, for example, 0.5 mm. The machining carried out with the milling tool 1 therefore represents a pre-machining of the cage blank 9.

(8) Despite the character of the machining carried out with the milling tool 1 as pre-machining, as far as the pocket bottom 13 is concerned, the geometric precision achieved therewith is already sufficiently high at this point to be able to dispense with material-removing post-machining. To achieve the required precision, the cutting inserts 3 arranged on the end face 7 are adjustable.

(9) In contrast to the front-side cutting inserts 3, the cutting inserts 4 are held in a fixed, non-adjustable position on the main body 2. For the finishing of the pocket wall, which is designated by 17 and has a spherically curved cross-section, a machining device 14 is used which is indicated only in FIG. 2 and which is also referred to as a control tool. A cutting insert 15 can be seen, which is assigned to the machining device 14 and is used in a second material-removing machining process in which only the pocket wall 17 is machined. The second material-removing machining process can take place either in the same setting as the first material-removing machining process or in a separate setting.

(10) In both cases, the good approximation of the shape of the milling tool 1 to the profile of the rolling elements to be guided in the comb-type cage 16 results in efficient material-removing machining. The comb-type cage 16 is made, for example, from a non-ferrous metal alloy.

REFERENCE NUMERALS

(11) 1 Milling tool

(12) 2 Main body

(13) 3 Cutting insert on the end face

(14) 4 Cutting insert on the lateral face

(15) 5 Cutting edge

(16) 6 Cutting edge

(17) 7 End face

(18) 8 Lateral face

(19) 9 Cage blank

(20) 10 Receiving opening

(21) 11 Cage ring

(22) 12 Web

(23) 13 Pocket bottom

(24) 14 Machining device

(25) 15 Cutting insert

(26) 16 Comb-type cage, rolling bearing cage

(27) 17 Pocket wall