Patent ID: 12259305

DETAILED DESCRIPTION

FIG.1shows a top view of a oscillating mill1for two grinding bowls2,3oscillating in a horizontal position. A pendulum drive of the oscillating mill1is of multi-part design with an eccentric shaft4mounted so as to be rotatable about a vertical eccentric axis and with two swing arms5,6, each mounted so as to be able to oscillate about vertical oscillation axes and connected to the eccentric shaft4via couplings. Grinding bowl holders7,8for the grinding bowls2,3are attached to the swing arms5,6. In addition, a motor unit10coupled to the eccentric shaft4via a V-belt9is provided for torque transmission. The eccentric shaft4is rotatably mounted on a base plate11. In addition, two bearing bolts12,13are attached to the base plate11, around which the swing arms5,6are rotatably mounted. Finally, the motor unit10is located on the base plate11. The eccentric shaft4, the bearing bolts12,13and the motor unit10together with the base plate11thus form a construction unit which can stand on a floor or subsoil via damping elements.

The motor unit10transmits a torque via the V-belt9to the eccentric shaft4. A rotary motion of the eccentric shaft4is converted via the couplings into an oscillating motion of the swing arms5,6. The oscillation frequency can be between 3 and 50 Hz, preferably up to 35 Hz. The oscillation path (double amplitude deflection) of the grinding bowl can be between 20 and 50 mm, preferably between 20 and 30 mm.

A tempering device not shown in detail can be used to temper grinding bowls2,3. To transport a tempering medium, which can be liquid or gaseous, from a stationary part14,15of the oscillating mill1to a grinding bowl holder7,8and to discharge the medium from the respective grinding bowl holder7,8to the stationary part14,15, each grinding bowl holder7,8is connected to two lines16,17. In each case, one of the two lines16,17is provided for the supply line, the other of the two lines16,17for discharging a gas or liquid medium, in particular liquid nitrogen, from the respective grinding bowl holder7,8.

The lines16,17are preferably designed as continuous uninterrupted pipelines. Lines16,17can be made of stainless steel or plastic, for example, or have stainless steel and/or plastic.

The design of the line routing is the same for both grinding bowl holders7,8, so that only one-line routing is described below as an example. The line arrangement with the lines16,17of one grinding bowl holder7is mirror-symmetrical to the line arrangement of the second grinding bowl holder8.

To compensate for relative movements between a grinding bowl holder7,8and the stationary part14,15assigned via the lines16,17during operation of the oscillating mill1, each line16,17has a compensating element18,19. The entire length of each line16,17is designed as a rigid pipeline, with the compensating element18,19being formed by a pipeline section of line16,17.

During operation of the oscillating mill1, the relative movements cause an oscillating deformation of the pipeline sections forming the compensating elements18,19, whereby the pipeline sections of the respective line16,17adjacent to the compensating elements18,19are deformed comparatively less. The design of the compensating elements18,19as rigid pipeline sections enables the compensation of relative movements without using line sections which are connected to each other in a rotatable and/or swiveling manner relative to each other. In particular, it is not necessary to use the rotary unions known from the state of the art to compensate for relative movements, so that a hermetically sealed, uninterrupted connection and a permanently leakage-free transport of the tempering medium between the grinding bowl holders7,8and the stationary parts14,15is ensured in a simple manner. In particular, it is not necessary to use sealing elements to compensate for relative movements, as is the case with rotary unions.

For the connection of lines16,17to the grinding bowl holders7,8on the one hand, and for the connection to the stationary parts14,15on the other hand, connection and accessory parts of the assembly technology known from the state of the art may be provided. The connection of the lines as such, i.e. decoupled from the compensation of relative movements, can be made by means of sealing material to enable a sealing connection between the respective line16,17and the grinding bowl holders7,8on the one hand and the stationary parts14,15on the other hand.

Each compensation element18,19is designed as a helical pipeline section with several coils or windings and is formed by essentially straight-line sections20and curved corner sections21. During the compensation of movement, the deformation of the line sections forming the compensating elements18,19decreases from coil to coil, so that the pipeline sections at the end of the respective last coil are essentially no longer deformed. As a result, the compensation of movement essentially takes place exclusively in the area of the compensating elements18,19.

The formation of the compensating elements18,19is done, for example, by forming, such as bending, straight pipe sections of the lines16,17.

The compensation elements18,19of two lines16,17connected to a grinding bowl holder7,8are designed as nested helixes. This compensates for relative movements in all spatial directions while requiring little space for the installation of the lines16,17inside the oscillating mill1.

The helically bent compensating element18,19or the respective pipeline section of the line16,17allows an increase in the line length compared to the line length with straight-line routing. This is shown schematically by comparison ofFIG.5, which shows helically bent compensating elements18,19, withFIG.6, which shows a prior art arrangement with straight-line routing. The ratio of the actual line length of a compensating element18,19to the line length L in the case of straight-line routing can be at least 5, preferably at least 10. This provides a sufficiently long line length to compensate for relative movements, to enable the compensation of relative movements with low stress and low deformation resistance.

In order to reduce the space required for the arrangement of the compensating elements18,19inside the mill1, the compensating element18is formed by a helix with, for example, four windings, while the nested internal compensating element19has five windings with a smaller circumference. It goes without saying that the type and design as well as the number of windings are to be understood as examples for the design of the oscillating mill1shown inFIGS.1to5.

Two lines16,17running parallel on each side of a grinding bowl holder7,8are connected to each other via screwed clamping and holding parts22,23. This prevents relative movements between the lines16,17from occurring in these line sections and compensates for movement primarily in the area of the helically bent compensating elements18,19.

The stationary parts14,15are rigid blocks of e.g. polytetrafluoroethylene (PTFE), which are fixed to the base plate11. The stationary parts14,15are decoupled from the vibrating movement of the grinding bowl holders7,8. Inside the stationary parts14,15, channels are provided for the passage and transfer of the tempering medium to or from a supply and/or disposal device24for the tempering medium. For this purpose, the stationary parts14,15are connected to the supply and/or disposal unit24via further pipelines.

REFERENCE CHARACTER LIST

1Oscillating mill2Grinding bowl3Grinding bowl4Eccentric shaft5Swing arm6Swing arm7Grinding bowl holder8Grinding bowl holder9V-belt10Motor unit11Base plate12Bearing bolt13Bearing bolt14Stationary part15Stationary part16Line17Line18Compensating element19Compensating element20Line section21Corner section22Holding part23Holding part24Supply and/or disposal device