DE10303208A1 - Production of conical spur wheels for beveloid automatic ore processing unit in a machine tool, involves producing spur wheels with teeth and head edge breaks formed in separate processing steps using same machine tool - Google Patents

Abstract

The method involves producing spur wheels with teeth and head edge breaks formed in separate processing steps using the same machine tool.

Description

The present invention relates to a process for the production of tapered spur gears for beveloid spur gears in a machine tool, with a broken head edge on each tooth head is trained.

Tapered spur gears, especially for beveloid spur gears, find more and more applications. To protect the teeth from damage in the manufacturing - testing - transport - and assembly process chain to protect, a head edge break is formed on the tooth head edge, since such damage knocking sounds can cause and must be avoided at all costs. Also the risk of injury the handling of sharp-edged workpieces by the worker at Assembly is reduced by the formation of head edge breaks.

Beveloid spur gear teeth preferably used in industrial robots and in ship gearboxes. So z. B. Beveloid spur gear teeth in the form of a reduced Planetary linkage - too Called Wolfrom theorem - in Industrial robots used, all wheels involute helical teeth have better engagement due to jump coverage and run smoothly. The sun gear and two ring gears are conical and form with a cylindrical Planetary gear, the so-called beveloid spur gear toothing. Become frequent the end edge breaks manually after the gear grinding educated.

The manufacture of the tapered spur gears itself is carried out on machine tools, which, for. B. are offered by the company "The Gleason Works" and in the EP 0690760 are described. This publication describes the formation of bevel gears and a method for feeding a tool to a predetermined depth in a workpiece.

Bevel gears are usually made up of two different ones Process manufactured: the hobbing process and the non-pass process.

In the gear shifting process, a rotating Advance tool into a workpiece to a predetermined depth. As soon as this depth is reached, the tool and the workpiece are in one predetermined relative rolling motion, known as gear rolling, about the axis of a theoretical generation wheel rolled as if the workpiece were engaged would rotate with the theoretical generation wheel, the teeth of the Generation wheel represented by the material removal surfaces of the tool are. The profile shape of the tooth is determined by the relative movement of the tooth Tool and workpiece while of gear rolling shaped.

Hobbing processes can be carried out in two categories are classified: face milling and gear hobbing. At the face milling each slot, i.e. H. the adjacent tooth sides of successive teeth one workpiece individually shaped. After the tool to a predetermined depth the rolling starts.

When rolling, the tooth surfaces can any number of known cycles can be formed. A tooth surface of a Slit can roll through a forward roll and the adjacent tooth surface by rolling backward be shaped. Alternatively, both sides of the tooth slot in one forward geared rolling process get cut. If a second or finishing cut required, this can be done by rolling backwards to the desired tooth surfaces produce. As soon as the tooth sides are completed, the tool relative to the workpiece withdrawn and then the workpiece to the next Slot position offset. The intermittent moving continues until all tooth surfaces of the workpiece are shaped.

Gear hobbing is a continuous transfer process, with a predefined timed rotation between the Tool and the workpiece the rolling gear is superimposed. In this way, all slots and therefore all tooth surfaces are open the workpiece through a single gear rolling process shaped. The workpiece and the tool is rotated in a timed relationship and the tool into the workpiece advanced, which removes material from all slots, while it is pushed deep. Once the full depth is reached the desired one begins Swarf, around all teeth the workpiece Completely train.

Non-geared processes that are either intermittent or continuous displacement are those where the Profile shape of a tooth on a workpiece directly from the profile shape of the tool is formed. The tool is pushed into the workpiece and the profile shape of the tool is given to the workpiece. Although there is no rolling is used is the concept of a theoretical generation wheel, also known as a gear rim, on non-hobbing processes applicable. The ring gear is that theoretical wheel whose tooth surfaces are too the tooth surfaces of the workpiece complementary are. The cutting knives therefore place the teeth of the ring gear on the tool when the tooth surfaces on the not rolled workpiece be shaped.

From the published in the name of "The Gleason Works" EP 0709157 a CNC-controlled machine for producing bevel gears is known. In such machine tools, cutting and / or grinding tools are arranged in such a way that the tools can represent a matching gear element which is in engagement with the workpiece gear just produced.

The one described in this publication Machine tool for forming longitudinally curved tooth spaces in bevel gears using a conically expanded tool that has material-removing surfaces is provided with a tool holder, which is mounted on a machine base, with an arrangement for rotating the conically widened tool in the tool holder about a tool axis , with a workpiece holder mounted on the machine base, with an arrangement for rotating a gear workpiece in the workpiece holder around a workpiece axis, with an arrangement to enable the relative translational movement between the tool holder and the workpiece holder along three orthogonal axes, and with an arrangement, to ensure the relative angular movement between the tool holder and the workpiece holder about a pivot axis. A computer control is also provided to simultaneously control the relative translational movements between the tool and the workpiece holder and the angular movement between the tool and the workpiece axes and to enable the relative movement between the conically expanded tool and the gear workpiece, so that the flared tool swings back and forth along the length of a tooth of the gear workpiece.

With tapered spur gears not, as is usual with cylindrical spur gears, by a kink in the bevel profile with larger normal pressure angle a chamfer is formed on the tooth head that breaks the head edge represents. For the production of beveloid spur gear teeth the axis of the milling machine pivoted about the cone angle. The paragraph on the cutter profile follows the cone angle, which generally differs from the cap cone angle. Consequently results for the Chamfer on the tooth head, d. H. the head edge break, a variable Size over the Tooth width. This, in turn, is usually not possible practical top edge break over to train the entire tooth width. The top edge break would be trapezoidal be, where it becomes too large on one side and thus the overlap downsized, d. H. that fewer teeth are engaged while he on the other hand may no longer exist.

Object of the present invention is a method of forming beveloid spur gear teeth to propose a practical one with little effort Head edge break over the entire tooth width is formed.

Based on a process of closer at the beginning the type mentioned is the solution this task with the features specified in claim 1; advantageous embodiments are described in the subclaims.

The invention therefore provides that the formation of the teeth and the formation of the top edge breaks in two separate operations in one and the same Machine tool can be done with only one clamping, two different tools are arranged in the clamping.

In a preferred embodiment used a gear cutting machine as the machine tool, which simultaneously can form two toothings, the conical spur gears by means of of a router milled or can be toothed with a cutting wheel or planing comb, whereby Cutters and Cutting wheel along the cone angle be led while the head edge breaks formed by a cutting wheel or a planing comb or a milling cutter that is guided along the head cone angle.

In another preferred embodiment the tapered spur gear is replaced by a first milling cutter and the end edge break through a second router successively formed, the two cutters together on a spindle are clamped and with the second cutter for the tip edge break through Move is positioned. The first router for the training of the tapered Spur gear is guided according to the cone angle during the second router for the Formation of the head edge break is performed according to the head cone angle.

The invention is illustrated below with the aid of the drawing, in which 1 schematically a side view of the tools required for performing the method and in 2 a top view of the tools is shown.

A workpiece A is machined to form spur gear teeth in accordance with 1 by means of a hobbing tool B designed as a milling cutter, the hobbing tool B about the axis 2 of the cone angle is passed as it goes through the line 1 and the corresponding processing line 1* is indicated on workpiece A. At the same time, a cutting edge C specially designed for this purpose can be used to form a head edge break on the gear that is being machined, namely by knocking. When thrusting, the path of the cutting wheel C or a planing comb D must run along the head cone angle, ie around the axis 2 be pivoted, as indicated by the pivot line 1 and the associated processing line 1* is indicated on workpiece A.

The cutting wheel C or the planing comb D is to be designed such that only the top edge of the Gear is processed. This tool is therefore more advantageous To design so that gears with the same normal module can be edited.

With the by 1 and 2 illustrated first exemplary embodiment of the method according to the invention, a machine tool is used with which two toothings are made at the same time can be formed.

As an alternative, it is too possible that on a milling machine two cutters can be clamped in combination on the same spindle are arranged and that the toothing and the top edge break are milled one after the other, the corresponding tool is positioned accordingly by shifting becomes. The corresponding tool is based on the angle of the foot cone or after the head cone angle.

As part of another alternative it is provided that two cutting wheels on a shaping machine be mounted on an axis and that the toothing and the top edge break encountered one after the other the appropriate tool by shifting accordingly is positioned. Furthermore, it is possible to put a cutting wheel through to replace a planing comb on a corresponding machine.

A

workpiece

B B '

generating tool

C

cutting wheel

D

planing comb

1, 1*

processing line

2, 2 *

cone angle

3

axis of rotation of the router

Claims (5)

Method for producing tapered spur gears for beveloid spur gear teeth in a machine tool, a head edge break being formed on each tooth head, characterized in that the formation of the teeth and the formation of the head edge breaks in two separate operations in one and the same machine tool with one clamping respectively. A method according to claim 1, characterized in that a gear cutting machine is used as the machine tool which permits corresponding tool combinations, a corresponding tool or a milling cutter (B), a cutting wheel (C) and / or a planing comb (D) being guided after the foot cone and cuts the gaps in the toothing and a corresponding tool or milling cutter (B), a cutting wheel (C) and / or a planing comb (D) after the head cone (tool axis ( 2 )) is guided and cuts the top edge break, the gear cutting and top edge break cutting processes being carried out simultaneously or in succession. A method according to claim 1 or 2, characterized in that that the tapered spur gear by a first cutter and the tip edge break through a second router are formed one after the other, with the two cutters together are clamped on a spindle and with the second cutter through axial method for the head edge break is positioned. A method according to claim 3, characterized in that the first router for the Training of the tapered spur gear is performed according to the cone angle. A method according to claim 3, characterized in that the second router for the Formation of the head edge break is performed according to the head cone angle.