DE1515072B1 - Honing tool for electrolytic honing with radially movable honing stone carriers - Google Patents

Description

1 2

It has already become known when honing under Preferably the cathode segments are used on honing conventional honing tools with in the tool at least the tool stroke longer Tool body sized radially displaceable honing stone as the workpiece. Bear the tool stroke the material removal on the workpiece is given by the length of the workpiece and the To accelerate the use of electrolysis. Da- 5 length as well as the overflow of the honing stones. Through this at is in the gaps between the work it is guaranteed that in every stroke position the anode tool body and the workpiece to be machined - switched workpiece surface in their full length surface a constant flow of an electrolyte liquid is opposite to a cathode surface and is therefore constantly sustained. The tool body is on the entire workpiece surface to be machined as an electrode negative pole of a power source connected io electrode surface is effective.

and forms the cathode while the workpiece is attached

the positive pole of the power source is connected to the honing tool shown in the drawing for loading

and forms the anode. working of a workpiece bore explained. It shows:

Honing with the aid of electrolysis F i g. 1 a longitudinal section of an inventive

is of particular importance when 15 ßen honing tool according to line I-I of Fig. 2,

large amounts of material are to be removed, Fig.2 shows a cross section along line II-II of the

because so far this has been done economically in the Honver- Fig. 1.

do not move due to very long machining times The cylindrical tool body marked with

was possible. per has an extension with at one end

A major disadvantage of the known method is the bayonet-like pin projections 3 on the side

for electrolytic honing it is that the distance connecting to the hollow drive rod of the honing

between cathode and anode with increasing machine. The tool body 1 takes in radial ^

Material removal is greater. As a result, longitudinal slots 4, which apart from an axial longitudinal hole f

the electrical contact resistance increases and tion 5 go through, radially movable flat stone

so that the current strength and the amount of material removed in the as holder 6, which is ceramic or baked in a groove

Unit of time decreases. This has a particular effect when it is lit-bound or with a diamond coating

from when a relatively large material honing stones 7 wear. Between the honing stones

quantity, that is to say a relatively strong material like 6, are likewise in except for the longitudinal bore 5

layer is to be removed from the workpiece. continuous radial longitudinal slots 8 of the work

During the electrolytic machining 30 tool body 1 slide 9 displaceable outside

it was already known that the electrode according to the tool body extends over the entire floor

the workpiece removal. When the elek- piece between the honing stone carriers 6 extending

Trolytic honing care was taken to ensure that segments 10 have.

a sufficient gap between the tool in the longitudinal bore 5 of the tool body 1 body, i.e. the cathode, and the workpiece are held in the same way as two rigidly connected to one another was, but there was an increase in split-directed cones 11 and 12, their cone parts width and thus a decrease in the electrolytic with corresponding inclined surfaces 13 and 14 or 15 Material removal in the course of machining as and 16 of the slide 6 and 9 cooperate. the considered quite acceptable. It was for example sliders 6 and 9 are close to their ends through also known, the last strokes entirely without current 40 ring springs 17 with the cones 11 and 12 in power supply to execute. Stopped and thus also against out-

The invention is based on the object of securing falling out of the tool body 1. the

Lowering of the electrolytic material removal Cones 11 and 12 are

to be avoided during the work process. tion 5 of the free end portion of the tool body Λ

This object is achieved according to the invention in that, in the case of a honing tool with a radially supported spring 18 in the position shown in FIG. 1 shown output sliding honing stone carrier, in which the work position is held and can be adjusted by means of the in the tool body to carry out a material removal accelerated by an electric drive spindle of the machine through a hydraulilyse as a cathode or mechanical drive and the workpiece is connected as an anode, between 5 ° Push rod 20, which engages on a pin extension 21 of the large segment-like cone, against the force of the spring 18 cathode pieces are arranged in such a way that they are displaced, with the honing radial adjustment movements of the honing stone carriers in ger6 with the honing stones 7 and the slider 9 participate to the same extent. As a result, the segments 10 are radially extended to the same extent that from the beginning to the end of the machining of the 55 outside until the honing stones 7 engage on the wall, the distance between the anode surfaces on the work- piece bore shift,
The honing tool is always the same as the machine and therefore the optimal conditions are used electrically insulated from the spindle and via an electrolytic material removal (e.g. slip ring on the negative pole of a power source, an optimal gap of 0.1 mm) stay connected to 60 low voltage. Practice this way. With the known method, the entire honing tool is actually a current-carrying conductor, and removal speeds of 0.8 to 1 mm / a very large cross-section. The honing stones? Minute reached, these values could, however, if they are not insulators themselves, in the removal of relatively strong material layer grooves of the slide 6, z. B. cannot be maintained by means of an adhesive. Used by the Auf- 65 film, isolated. Current can therefore only maintain an optimal gap, this possibility is given by the possibility between the bore wall and the possibility, however, with the tool according to the invention. borrowed segments 10 flowing electrolyte flow,

the segments 10, the cathode and the bore wall of the to the positive pole of the power source connected workpiece forms the anode. The radial current path through the electrolyte remains the same each setting of the honing stones 7 constant, since the segments 10, the radial setting movements of the Participate in honing stones to the same extent. This ensures that the current strength and so that the material removal on the workpiece remains the same. ίο

In Fig. 1 shows a workpiece W of length L1 , the honing tool being located at one end of the stroke. The tool stroke H is chosen so that the honing stones of length L 2 run over the workpiece on both sides by an amount α. In the exemplary embodiment, the entire length L 3 of the segments 10 connected as cathodes is greater than the workpiece length L 1 by the stroke length H. Therefore, the segments 10 do not reveal parts of the workpiece bore in any stroke position. The wall of the workpiece bore therefore remains effective as an electrode surface in its entirety. Since the electrode spacing also remains the same, the contact resistance and thus the current strength that determines the material removal is not changed at any moment.

Claims (4)

Patent claims: 1. Honing tool for electrolytic honing with radially movable honing stone carriers the tool body is connected as the cathode and the workpiece as the anode, thereby characterized in that between the honing stone carriers (6) large-area segment-like cathode pieces (10) are arranged in such a way that they counteract the radial adjustment movements of the honing stone carrier participate to the same extent. 2. Honing tool according to claim 1, characterized in that the cathode segments (10) are longer than the workpiece by at least the tool stroke (H), which is determined from the length (Ll) of the workpiece, the length (L 2) of the honing stones ( 7) and the overflow (a) of the latter. 3. Honing tool according to claim 1 or 2, characterized in that it is known per se Way as a whole as a live conductor is connected to the power source. 4. Honing tool according to one of claims 1 to 3, characterized in that the honing stones (7) isolated in a manner known per se from the current-carrying honing stone carriers (6) are. 1 sheet of COPY drawings