Mixer having rotating mixing container

Abstract

The present invention relates to a mixer with a mixing container and a tool shaft (8) which is arranged at least partly in the mixing container and has a drive end and a working end for a working tool (6), the tool shaft (8) being mounted on the drive end by means of two mutually set-apart tool bearings and a drive motor (7) being provided for the tool shaft (8). In order to provide a mixer which is simple and economical to manufacture and has as few movable and wearing parts as possible and the tool shaft (8) of which is, in addition, able to accommodate the considerable transverse forces occurring during operation, the invention proposes that the drive motor (7) have a motor shaft which is mounted, at least on one side, by a tool bearing.

Claims

1. A mixer with a mixing container and a tool shaft (8) arranged at least partly in the mixing container, the tool shaft having a working end to which a working tool (6) is fastened or can be fastened and a drive end which is mounted by means of two mutually set-apart tool bearings, a drive motor (7) being provided with a motor shaft (21) for driving the tool shaft (8), wherein the motor shaft (21) is mounted by at least one of the two mutually set-apart tool bearings, and wherein one of the bearings, is a combined radial axial bearing (radiax bearing) (19).

2. The mixer according to claim 1, wherein the motor is arranged between the two tool bearings and the motor shaft (21) is mounted by means of the two tool bearings, so that the tool shaft also serves as the motor shaft.

3. The mixer according to claim 1 or 2, wherein the motor is a direct drive, three-phase synchronous motor.

4. The mixer according to claim 2, wherein the diameter of the motor shaft (21) differs on the two tool bearings.

5. The mixer according to one of claims 1 to 2, wherein the motor is arranged in a motor housing (16), both tool bearings being arranged on or in the motor housing (16).

6. The mixer according to claim 5, wherein the motor housing (16) has a first outer flange (13) and the mixer has a mixer housing (2) in which the mixing container (3) is arranged, the outer flange being fastened to the mixer housing.

7. The mixer according to claim 6, wherein the motor housing (16) has a second outer flange (17) which is also fastened to the mixer housing, the second outer flange (17) having a larger average diameter than the first outer flange (13).

8. The mixer according to claim 7, wherein the mixer housing has a stepped through-opening with a first portion having a smaller average diameter and a second portion having a larger average diameter, the second portion having an average diameter which is larger than the average diameter of the first outer flange (13) and is smaller than the average diameter of the second outer flange (17).

9. The mixer according to claim 8, wherein said first portion of said stepped through-opening has a smallest diameter and the smallest diameter is larger than the largest external diameter of the working tool (6).

10. The mixer according to one of claims 1 to 2, wherein the tool shaft (8) has two portions which are detachably fastened to each other, one of the portions being formed in one piece with the motor shaft (21).

11. The mixer according to one of claims 1 to 2, characterized in that the tool shaft (8) and the motor shaft (21) are formed in one piece.

12. The mixer according to claim 3, wherein the motor is any one of a torque motor, a servo motor and a reluctance motor.

13. The mixer of claim 1, wherein one of the bearings is arranged closer to the working end of the tool shaft.

14. The mixer of claim 4, wherein the two tool bearings include a tool bearing (18) facing the mixing container (3) and a tool bearing (19) remote from the mixing container (3), and wherein the diameter of the motor shaft (21) on the tool bearing remote from the mixing container (3) is the smaller diameter.

15. The mixer of claim 14, wherein the diameter of the motor shaft (21) on the tool bearing (19) remote from the mixing container (3) is at least 30% smaller than the diameter of the motor shaft (21) on the tool bearing (18) facing the mixing container (3).

16. The mixer of claim 14, wherein the diameter of the motor shaft (21) on the tool bearing (19) remote from the mixing container (3) is at least 50% smaller than the diameter of the motor shaft (21) on the tool bearing (18) facing the mixing container (3).

17. The mixer of claim 6, wherein the mixer housing (2) is provided with a housing cover (5), and wherein the outer flange is fastened to the housing cover (5).

18. The mixer of any one of claims 1-2, wherein one of the bearings is a twin-row self-aligning bearing.

19. The mixer of any one of claim 1-2, wherein the combined radial axial bearing is any one of a self-aligning roller bearing and a self-aligning ball bearing.

Description

(1) Further advantages, features and possible applications of the present invention will become clear from the following description of preferred embodiments and also from the associated figures, in which:

(2) FIG. 1 is a vertical section through a mixture of the prior art;

(3) FIG. 2 is a vertical section through a first embodiment according to the invention; and

(4) FIG. 3 is a vertical section through a second embodiment according to the invention.

(5) FIG. 1 shows a prior art embodiment which has already been described at the outset.

(6) FIG. 2 shows a first embodiment according to the invention. Where possible, the same reference numerals have been selected for the same parts of the mixer that have already been shown in FIG. 1 and discussed. In FIG. 2 the drive motor 7 is received in a motor housing 16, the motor housing 16 being fastened to the mixer cover 5 by means of two outer flanges 13, 17. It may be seen that the tool shaft 8 functions at its drive end at the same time as the motor shaft 21. The motor shaft 21, which in the embodiment shown is embodied partly as a hollow shaft, is held by the self-aligning roller bearing 18 and also the radial bearing 19. The second outer flange 13, which is more faced toward the product space, i.e. the mixing container, has a smaller external diameter than the first outer flange 17. As a result, the entire motor can be inserted into the housing cover 5 from the outside, so that first the outer flange having the smaller external diameter is inserted into a correspondingly stepped hole in the container cover until it rests against the bottom of the extended hole. The spacing of the two outer flanges 13, 17 is designed in such a way that, in the situation shown in FIG. 2, both flanges can be screwed to the housing cover 5.

(7) If required, the motor can thus easily be detached from the housing cover and removed.

(8) A situation of this type is shown in FIG. 3 which at the same time shows a second embodiment according to the invention of the mixer. In this case, the motor, along with the working tool 6, has been detached from the housing cover 5, so that the motor, along with the working tool 6, can be removed from the corresponding opening in the container cover. The embodiment shown in FIG. 3 differs from the embodiment shown in FIG. 2 in that the flange connection 10 is missing, so that in this case the tool shaft and motor shaft are formed in one piece. In both embodiments shown, the axis of rotation of the working tool is arranged eccentrically to the axis of rotation of the mixing container.

(9) The integration of the motor into a robust bearing unit for accommodating the forces and moments of the working tool produces a unit having minimal maintenance costs and the highest possible reliability. Only one shaft is guided in two bearings. This shaft takes over both the forces of the motor (for example weight forces, magnetic residual forces) and the forces of the working tool (vortexer, kneader, etc.). Any necessary variation of the rotational speed may be facilitated by the use of a frequency converter.

LIST OF REFERENCE NUMERALS

(10) 1 Mixer 2 Mixer housing 3 Mixing container 4 Ball bearing 5 Housing cover 6 Working tool 7 Drive motor 8 Tool shaft 9 V-belt 10 Flange connection 11, 12 Tool bearing 13 Flange 14, 15 Motor bearing 16 Motor housing 17 Flange 18 Self-aligning roller bearing 19 Radial bearing 20, 21 Motor shaft 22 Opening for assembly tool