Hydrodynamic clutch

A hydrodynamic clutch with a generally horizontal axis, specifically for underground operation. The clutch includes a primary wheel, a secondary wheel, a housing which comprises two essentially axially perpendicular end walls as well as a peripheral wall which is essentially concentric to the axis of the clutch, a scooping bowl fastened to the primary wheel, forming a scooping space and revolving jointly with the primary wheel (rotor), outlet bores discharging from the working space into the scooping space, and a scooping pipe dipping into the scooping space. At least one antechamber has an inlet port for receiving leakage water entrained and thrown off by the outside surface of the rotor. A line is used for transfer of operating fluid from the antechamber to the scooping space.

BACKGROUND OF THE INVENTION 
The invention concerns a hydrodynamic clutch. The hydrodynamic clutch is of 
the type having an essentially horizontal axis, specifically for 
underground operation. A primary wheel is seated on a drive shaft, and a 
secondary wheel is seated on an output shaft. A housing comprises two 
essentially axially perpendicular end walls and, relative to the clutch 
axis, an essentially concentric peripheral wall. A scoop bowl is fastened 
to the primary wheel, forming a scooping space, and revolving jointly with 
the primary wheel. Outlet bores discharge from the working space into the 
scooping space, and a scooping pipe dips into the scooping space. 
Such a clutch is known from the German utility patent 7,913,100. On this 
clutch, the housing comprises in its lower part a collection container for 
an operating fluid sump, additionally an upright container into which 
fluid from the sump is pumped, and lastly a splash disk which dips into 
the sump and lifts the fluid to the level of the collection container. 
Clutches of this type may be either regulated or unregulated. Presently, 
they predominantly concern applications in underground operations. Here, 
the clutch is generally operated with water representing the operating 
fluid, frequently pit water. 
Outlet bores are provided on the inside and outside diameters of the 
working circuit, so as to constantly release from the working space a 
certain amount of the operating fluid, i.e., of the water, and to 
circulate it for cooling purposes. These outlet orifices empty into a 
concomitantly rotating scooping space, or discharge into the clutch 
housing. The scooping space, i.e., the space between primary wheel and 
scooping bowl, is emptied by a scooping pipe, which then feeds the 
discharged operating fluid into a return system. 
However, the operating fluid does not only accumulate in the scooping 
space. A sump is formed also outside the scooping bowl, between the outer 
peripheral surface of the scooping bowl and the inside surface of the 
peripheral wall of the housing where leakage fluid accumulates. Removal of 
this leakage fluid is critical for the following reasons: in view of the 
space constrictions underground, it is naturally desired to keep the outer 
dimensions of the clutch housing as small as possible. Therefore, also the 
gap space between the outside surface of the scooping bowl and the inner 
peripheral surface of the housing is small. Thus, there is no room for the 
arrangement of pumps or pump type units. Nonetheless, removal of the 
leakage fluid must be ensured, since during operation--due to rotor 
leakage or overflow--operating fluid constantly flows into the housing. 
The problem underlying the invention is to so design a clutch such that the 
leakage fluid between scooping bowl and housing will be removed reliably, 
with little construction expense, and without appreciable energy losses. 
SUMMARY OF THE INVENTION 
This problem is solved by the features of the present invention. 
A hydrodynamic clutch with a generally horizontal axis is provided.. The 
hydrodynamic clutch includes a primary wheel seated on a drive shaft, a 
secondary wheel seated on an output shaft, and a housing. The housing 
comprises two essentially axially perpendicular end walls, and relative to 
the clutch axis, an essentially concentric peripheral wall. A scoop bowl 
is fastened to the primary wheel, forming a scooping space, and revolving 
jointly with the primary wheel. The hydrodynamic clutch further includes 
outlet bores discharging from the working space into the scooping space, a 
scooping pipe dipping into the scooping space, at least one antechamber 
with an inlet port for receiving leakage water entrained and thrown off by 
the outside surface of the primary wheel, and a line for transfer of 
operating fluid from the antechamber into the scooping space.

DETAILED DESCRIPTION OF THE INVENTION 
The clutch is fashioned as a double clutch, but may be fashioned also with 
a single circuit. Here, it features two toroidal working spaces, each 
formed by a primary wheel (pump wheel) and a secondary wheel (turbine 
wheel). The two primary wheels 1.1 and 1.2 are driven by a drive shaft 2. 
The two secondary wheels 3.1 and 3.2, are nonrotationally secured to an 
output shaft 4. The two primary wheels 1.1 and 1.2 are nonrotationally 
connected to one another by a cylinder section 5, which extends beyond the 
working space illustrated in FIG. 1, right. This cylinder section features 
an enlargement which acts as a splash disk 6 and, in relation to the two 
working spaces, extends symmetrically in axial direction. Moreover, in 
FIG. 1, the cylinder section 5 is extended beyond the working space shown 
at right, so that it forms a scooping space 7. Thus, the scooping space 7 
revolves with the cylinder section 5. 
Also provided are quantity-regulable bores, or dosing valves 8, as shown in 
the section of FIG. 1. By way of this dosing valve 8, operating fluid 
proceeds into the scooping space. Also provided is a scooping pipe 9. The 
entire operating fluid is fed via this scooping pipe to a collection 
container, for instance an upright container, or directly into a drain 
line, or proceeds in direct circulation via a cooling unit back into the 
working circuit. 
According to the invention, antechambers 10.1 and 10.2 are provided. These 
feature each an inlet port 11.1, 11.2 and are equipped with a stripping 
edge 12.1, 12.2. The two stripping edges are of such design and 
arrangement that the leakage fluid entrained by the splash disk 6 will on 
its upward path be stripped and passed into the appropriate antechamber. 
Due to the dual arrangement of the two antechambers 10.1, 10.2 and the 
illustrated design and arrangement of the stripping edges, operation in 
both directions of rotation is possible. Leakage fluid is stripped off the 
splash disk 6 at any rate. 
Lines 13.1 and 13.2 are shown, connecting the appropriate antechamber with 
the scooping space 7. 
The clutch features a housing 14. Housing 14, relative to the clutch axis, 
comprises an essentially concentric peripheral wall 15 as well as two 
essentially disk-shaped end walls 16.1 and 16.2. In the embodiment shown, 
the two antechambers 10.1 and 10.2 are formed utilizing the peripheral 
wall 15 of the housing 14. It is understood that in this respect there are 
also other options available. As shown in FIG. 2, the antechambers are 
suitably situated at the level of the axial center plane and extend 
peripherally a certain distance beyond this center plane. 
It may be suitable to fashion the peripheral wall 15 of the housing in such 
a way that the gap between the inner shell surface of the peripheral wall 
15 and the outer shell surface of the splash disk 6 increases continuously 
up to the inlet port 11.1, or 11.2. 
The arrangement of the clutch is such that its axis extends horizontally, 
but the clutch may also be used at an inclined to vertical orientation. 
According to the invention, operating fluid collecting in the housing due 
to leakage, or via discharge orifices, or at clutch shutoff, is at 
start-up fed into the antechambers by means of splash disk 6. Concurrent 
losses due to acceleration and disk friction are minimal. 
The operating fluid then flows, unpressurized, from the antechambers into 
the concomitantly revolving scooping space 7. 
While this invention has been described as having a preferred design, the 
present invention can be further modified within the spirit and scope of 
this disclosure. This application is therefore intended to cover any 
variations, uses, or adaptations of the invention using its general 
principles. Further, this application is intended to cover such departures 
from the present disclosure as come within known or customary practice in 
the art to which this invention pertains and which fall within the limits 
of the appended claims.