CHARGING APPARATUS FOR THE DIMENSIONALLY STABLE HEAT TREATMENT OF WORKPIECES

Abstract

The invention relates to a charging apparatus for the dimensionally stable heat treatment of workpieces (1), in particular those of a disk or ring shape, having a charging rack (10) for horizontally mounting the workpiece (1), wherein at least s three screw-type mandrels or ball joint mandrels (2) are arranged on the charging rack (10), the ball joint mandrels (2) having a base plate (3) with a female thread (7), a screw element (4) with a male thread (7) matched to the female thread (7) and a head that has a spherical segment surface, as well as a pressure piece (5) matched precisely to the spherical segment surface of the head and arranged movably thereon.

Claims

1. Charging apparatus for the dimensionally stable heat treatment of workpieces, in particular those of a disk or ring shape, having a charging rack (10) for horizontally mounting the workpiece (1), characterized in that at least three screw-type mandrels or ball joint mandrels (2) are arranged on the charging rack (10), wherein the ball joint mandrels having a base plate (3) with a female thread (7), a screw element (4) with a male thread (7) matched to the female thread (7) and a head that has a spherical segment surface, and a pressure piece (5) matched precisely to the spherical segment surface of the head and arranged movably thereon.

2. Charging apparatus according to claim 1, characterized in that the screw-type mandrels are threaded into the charging rack in a height-adjustable manner.

3. Charging apparatus according to claim 1, characterized in that charging rack (10) and ball joint mandrels (2) are manufactured from a heat-resistant steel.

4. Charging apparatus according to claim 1 comprising a charging rack (10) in the form of a grating or a star having several arms (11).

5. Charging apparatus according to claim 4, characterized in that the charging rack (10) has six to nine arms (11).

6. Charging rack according to claim 4 or 5, characterized in that the number of mandrels (2) corresponds at least to the number of spokes (11).

7. Charging rack according to claim 1, characterized in that the mandrels (2) have a trapezoidal thread (7).

8. Charging apparatus according to claim 1, characterized in that the ball joint mandrels (2) are provided with a lubricant, in particular a copper paste, between the head and the pressure piece (5) and/or on top of the pressure piece (5).

9. Charging apparatus according to claim 1 with workpiece (1), in particular a gearwheel, placed on it.

10. Method for the dimensionally stable heat treatment of workpieces having a disk or ring shape comprising the following steps: Provision of a charging rack (10) in the form of a spoke wheel; Arranging at least three screw-type mandrels or ball joint mandrels (2), on the charging rack, wherein said ball joint mandrels (2) have a base plate (3) provided with a female thread (7), a screw element (4) with a male thread (7) matched to the female thread (7) and a head shaped in the form of a spherical segment as well as a pressure piece (5) matched precisely to the spherical ball segment surface of the head on which it is movably arranged; Mounting the workpiece (1) on the mandrels (2); Alignment of the mandrels (2); Applying heat to the workpiece (1) over a desired period of time; Quenching/cooling the workpiece (1) in a customary cooling medium and If required or expedient, tempering the workpiece (1).

11. Method according to claim 10, characterized in that a charging rack (10) is used that is provided with six to nine arms.

12. Charging rack according to claim 11, characterized in that the number of mandrels (2) corresponds at least to the number of spokes (11) of the charging rack (10).

13. Method according to claim 10, characterized in that the contact surfaces (6) of the pressure pieces (5) of the ball joint mandrels (2) are lubricated via the screw element (4) and/or the workpiece (1).

14. Use of ball joint mandrels in a charging apparatus for the dimensionally stable heat treatment of workpieces in horizontal position, wherein said ball joint mandrels (2) have a base plate (3) provided with a female thread (7), a screw element (4) with a male thread (7) matched to the female thread (7) and a head shaped in the form of a spherical segment as well as a pressure piece (5) matched precisely to the spherical segment surface of the head on which it is movably arranged.

Description

[0029] The invention is explained in more detail by way of the enclosed figures where

[0030] FIG. 1 shows a side view as well as a view from below of a gearwheel mounted on ball joint mandrels as provided by the invention;

[0031] FIG. 2 is an enlarged representation of section A shown in FIG. 1;

[0032] FIG. 3: illustrates a variant of a ball joint mandrel as a sectional view seen from the side; and

[0033] FIG. 4 is a representation of a star-shaped charging element, as it can be used as a charging rack according to the invention.

[0034] From FIG. 1a a gearwheel 1 with gearteeth shown on the outside can be seen mounted on 6 ball joint mandrels 2. FIG. 1b shows the same gearwheel seen from below with the ball joint mandrels 2 evenly distributed over the circumference, said mandrels supporting the gearwheel on a charging rack (not shown). The ball joint mandrels are neither permanently connected to the gearwheel nor to the charging rack.

[0035] In FIG. 2 section A from FIG. 1a is illustrated showing gearwheel 1 and the ball joint mandrel 2 said ball joint mandrel consisting of the base plate 3 accommodating the screw element 4. Via the head of the screw element 4 the pressure piece 5 is supported, on which the gearwheel 1 is mounted.

[0036] FIG. 3(a) is a side view of a ball joint mandrel 2 with the base plate 3, the screw element 4 and the pressure piece 5. FIG. 3(b) is a view of the ball joint mandrel along the section line C-C with the screw element 4 being threaded into the base plate 3. The screw element 4 is provided with a male thread that engages with a female thread 7 of the base plate 3. Preferably, the female thread is a trapezoidal thread.

[0037] Furthermore, screw element 4 has a hexagonal head which allows the use of a wrench. The top head surface 6 has the shape of a spherical segment, same as, complementary thereto, the lower surface of the pressure piece 5. The pressure piece 5 can thus move freely in all directions on the head of the screw element 4.

[0038] In particular, the pressure piece is thus able to compensate for oblique positions of the charging rack and/or balance out the surfaces of the workpiece that deviate from the horizontal.

[0039] As already mentioned, a lubricant can be applied to the spherical ball segment surface 6 as well as the surface of the pressure piece 5 with a view to minimizing friction between the screw element 4 and the pressure piece 5, and the pressure piece 5 and the workpiece 1, respectively.

[0040] FIG. 4 finally shows a charging rack 10 in the form of a star, which is suitable for the horizontal accommodation of a disk-shaped or ring-shaped workpiece. The screw mandrels or ball joint mandrels 2 are placed at regular intervals on the charging rack, preferably one mandrel in the area of each arm 11, whereupon the workpiece is then placed.