Inductive hardening machine

Abstract

A machine for inductively hardening a workpiece has a stationary frame, a holder on the frame adapted to secure the workpiece in a workspace, and a control housing fixed on the frame and containing a transformer. A slide is movable on the frame relative to the workspace and carries an inductor juxtaposable with the workpiece in the workspace. A flexible high-current cable extends between the fixed transformer and the movable slide for feeding electricity from the transformer to the inductor.

Claims

1. A machine for inductively hardening a workpiece, the machine comprising: a stationary frame; a holder on the frame adapted to secure the workpiece in a workspace; a control housing fixed on the frame; a transformer fixed in the control housing connectable to line for converting incoming line voltage to an alternating-current output voltage of a predetermined amperage, frequency, and voltage; a slide movable on the frame relative to the workspace and to the workpiece therein; an inductor carried on the slide and juxtaposable with the workpiece in the workspace; and a flexible high-current cable extending between the fixed transformer and the movable slide for feeding the output voltage from the transformer to the inductor.

2. The hardening machine defined in claim 1, wherein the control housing and transformer are outside the workspace.

3. The hardening machine defined in claim 1, wherein the cable is a coaxial cable.

4. The hardening machine defined in claim 1, further comprising a fitting on the slide through which the cable is connected to the inductor.

5. The hardening machine defined in claim 1, wherein the holder includes means for rotating the workpiece about an axis in the workspace.

6. The hardening machine defined in claim 1, further comprising: a tower on the frame adjacent the workspace, the slide being carried and movable on the tower.

7. The hardening machine defined in claim 6, further comprising: a guide on the frame for movement of the tower on the frame relative to the workspace.

8. The hardening machine defined in claim 7, wherein the tower is movable horizontally relative to the workspace and the slide is moveable vertically on the tower.

9. The hardening machine defined in claim 6, wherein the tower is between the control housing and the workspace.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing whose sole FIGURE is a schematic view of an inductive hardening machine according to the invention.

SPECIFIC DESCRIPTION OF THE INVENTION

(2) As seen in the drawing, a hardening machine 1 has a frame 17 provided with a headstock 3 and tailstock 4 that can hold a workpiece, here a crankshaft 2 having crankpins 2 and bearings 2, in a workspace 14 and rotate it about a here vertical axis A that passes centrally through the bearings 2. Adjacent the workspace 14 is a column 7 movable horizontally in a direction x on rails 15 of the machine 1 toward and away from the workspace 14. This column 7 carries vertical rails 16 on which a mount 6 carrying a saddle-shaped inductor 5 can travel in a direction z along the axis A of the workspace 14.

(3) According to the invention a stationary control housing 8 is fixed on the frame 17 of the machine 1 and holds a massive transformer 10 that converts incoming line voltage to alternating current of the amperage, frequency, and voltage required by the inductor 5. This current passes through a flexible coaxial cable 9 from the stationary control housing 8 to a fitting 11 on the tool mount 6, and thence passes to the inductor 5. The coaxial cable 9 has a conductive core 12 surrounded by a conductive sheath 13.

(4) Since the cable 9 is flexible, the tower 7 and mount 6 can move quickly and freely to juxtapose the inductor 5 with the bearings 2 and inductively heat them, while the heavy transformer 10 sits in the control housing 8, which can be provided with an appropriate coolant system for the transformer 10.

(5) The fact that this transformer 10 does not have to be moved, allows actuators, such as shown schematically at 18, for the slide 6 and tower 7 to be relatively small and fast-acting.