Transmission for a two-worm press with counter running worms

A transmission for a two-worm press with two counter-running worms, which includes two transmission output shafts respectively connectable to the two counter-running worms, first gears laterally offset relative to each other. These first gears are drivingly interconnected by second gears forming intermediate gears. The transmission also includes a bearing housing detachably connected to a transmission housing which houses axial bearings for the transmission output shafts and also houses the bearings for the intermediate gears. The bearing housing is connected to the worm housing of the two-worm press by means of the rods extending through the transmission housing. One of the transmission output shafts is firmly connected to a first extension shaft so that the latter is rotatable with said one transmission shaft. This extension shaft extends through the bearing housing and has its output end axially supported by and connected to an output shaft of a stepdown transmission the housing of which is detachably connected to the bearing housing. The second transmission output shaft is connected to a second extension shaft which is journalled in the bearing housing by means of an axial bearing forming a tandem bearing.

The present invention relates to a transmission for a two-worm press with 
counter-running worms the transmission output shafts of which are provided 
with teeth laterally offset relative to each other and which through 
intermediate gears mesh each other. The transmission according to the 
present invention is provided with a bearing housing screwed to the 
outside of the transmission housing for receiving the axial bearings which 
serve for supporting the transmission output shafts, said bearing housing 
being connected to the worm housing by means of tie rods extending through 
the transmission housing. 
Transmissions for two-worm presses with counter-running worms have become 
known in which the gears necessary for reducing the speed and located 
between the driving motor and the worms are arranged in a single 
transmission housing. The axial forces of the two worms are through 
axially displaceable transmission output shafts transmitted to the axial 
bearings which are arranged on that side of the transmission housing which 
faces away from the worm housing. By means of tie rods which on one hand 
are connected to the housing of the axial bearing and on the other hand 
are connected to the worm housing and in a contact-free manner are passed 
through the transmission housing, the worm back pressure forces are 
returned from the axial bearing to the worm housing. 
These transmissions have the drawback that with regard to dimensions and 
arrangement of the gears, especially in the transmission end stage on the 
side of the worms, said transmissions are designed only for a definite 
distance between the worms and for a definite admissible torque load so 
that these transmissions represent single purpose transmissions inasmuch 
as they are not usable for different distances between the worms and 
cannot be used for higher torques deviating from the once selected design. 
It is an object of the present invention so to design a transmission of the 
above mentioned general type that with slight structural changes it can be 
adapted to different requirements with regard to the distance between the 
worms and with regard to the torques.

The transmission according to the invention is for a two-worm press with 
counter-running worms and is characterized primarily in that the two 
transmission output shafts together with intermediate gears are 
individually journalled in a transmission housing, and that one of said 
transmission output shafts is nonrotatably connected to an extension shaft 
extending through the bearing housing, and, supported in axial direction, 
is connected to the output end of an output shaft of a step-down 
transmission screwed onto a bearing housing, said output shaft being 
provided with a preceding additional axial bearing. The second 
transmission output shaft is connected to an extension shaft which by 
means of an axial bearing designed as a tandem bearing is arranged in the 
bearing housing. 
Referring now to the drawings in detail, the section A-A' comprises the 
front region of the transmission housing 3 which extends over the distance 
x in FIG. 2. The section B-B' covers the region of the transmission 
housing 1 and the bearing housing 11, which region is designated with the 
letter Y. The section C-C' covers the region of the built-on step-down 
transmission with the housing 16 which last mentioned region is designated 
with the letter Z. With the transmission illustrated in FIGS. 1 and 2 for 
a two-worm press, the two transmission output shafts 1 and 2 are by 
non-illustrated radial bearings journalled in a transmission housing 3. 
The transmission output shafts 1 and 2 are at their splined ends 1a and 2a 
by non-illustrated coupling sleeves nonrotatably connected to the 
non-illustrated drive ends of the worms. The transmission output shafts 1 
and 2 are furthermore provide with spur gears 1b, 2b which are laterally 
offset with regard to each other. Gear 1b, driven by shaft 1, meshes with 
gear 4a to drive gear 4b which is fixed thereto. Gear 4b meshes with gear 
5 which engages gear 2b fixed on shaft 2, so that the two output shafts 1 
and 2 will drive a two-worm press. The intermediate gears 4a and gear 4b 
are nonrotatably connected to each other. The intermediate gears 4a, 4b 
and 5 are rotatably journalled on hollow intermediate shafts 6 and 7, 
respectively, which are fixedly journalled in the transmission housing 3. 
Two of the total of four tie rods 8 are passed through the hollow 
intermediate shafts 6 and 7. These two tie rods 8 have their end faces 
rest on one hand against the flanged surface of the worm housing 10 of 
which only an cutout is shown and, on the other hand against the flanged 
surface of the bearing housing 11. The said two tie rods 8 are 
respectively connected to the respective surfaces engaged thereby, by 
screws 12 and 13 extending through said flanged surfaces. The length of 
the four tie rods 8 is with this arrangement slightly greater than the 
distances between the two end faces of the transmission housing 3 which 
last mentioned distance is designated in FIG. 2 with the character G. The 
bearing housing 11 is on one hand connected by non-illustrated screws to 
the transmission housing 3 and has its oppositely located end face by 
means of screws 9 connected to an intermediate plate 14 which in its turn 
is by means of screws 15 connected to the transmission housing 16 of a 
step-down transmission. This step-down transmission with its drive shaft 
17, the intermediate shaft 18, and the transmission output shaft 19 with 
the additional axial bearing 20 arranged on the outside of the 
intermediate plate 14 on the transmission housing, corresponds in its 
construction to a transmission for driving one worm presses. 
The non-rotatable connection between the transmission output shaft 19 of 
the step-down transmission and the transmission output shaft consists of 
an extension shaft 24 passed through the bearing housing 11. This 
extension shaft 24 is on one hand through a splined coupling sleeve 21 
connected to the correspondingly designed end of the transmission output 
shaft 1 and on the other hand corresponds to a splined shaft end in the 
correspondingly designed hub and of the transmission output shaft 19. 
Thus, the worm back pressure force acting upon the transmission output 
shaft 1 in axial direction is transmitted to the preceding axial bearing 
10 of the step-down transmission and from there is through the 
intermediate plate 14, the bearing housing 11, and the tie rods 8 returned 
to the worm housing. 
The worm back pressure force acting upon the transmission output shaft 2 is 
by means of an extension shaft 22 conveyed to the axial bearing 23 which 
is arranged in the bearing housing 11 and designed as tandem bearing, and 
is likewise through the intervention of the tie rods 8 returned to the 
worm housing. 
For adapting the transmission according to the invention to different 
distances between the worms, it is merely necessary to exchange the 
transmission part with the transmission output shafts 1 and 2 and the 
intermediate shafts. The adaptation to greater axial forces can be 
effected by exchanging the axial bearing 23. The step-down transmission 
can in the above mentioned cases be retained without any changes. 
As will be evident from the above, the advantage according to the present 
invention consists primarily in that merely the transmission part with the 
transmission output shafts 1, 2 and the bearing housing 11 of the 
respective distance between the worms has to be produced while as 
step-down transmissions, mass produced transmissions of one worm presses 
can be employed. 
It is, of course, to be understood that the present invention is, by no 
means, limited to the specific showing in the drawings, but also comprises 
any modifications within the scope of the appended claims.