Arrangement for automatic displacement of a cutter set of a meat comminuting machine

A meat comminuting machine has a cutting unit which includes at least one stationary perforated plate and a mobile associated cutter head arranged on a driving shaft, which is driven by a driving motor, and a device for an axial displacement of the driving shaft which supports the cutter head in dependence of the loading of the driving motor.

BACKGROUND OF THE INVENTION 
The present invention relates to the meat comminuting machine, and more 
particularly it relates to a meat comminuting machine which has has a 
cutting unit with at least one stationary perforated plate and a 
replaceable cutter head, which is associated with the perforated plate and 
arranged on a shaft drivable by a motor. 
Meat comminuting machines of the above-noted general type, are known in the 
art. A known meat comminuting machine has been known to be afflicted with 
the problem that the cutter blades which are provided on the cutter head 
and operate with the perforated blade are subjected to a very fast wear, 
particularly during a continuous running of the comminuting machine. This 
means, however, that the individual cutter blades must be ground within a 
relatively short time, so that the required grinding not only involves 
additional working expenses, but also requires every time a special 
disassembly of the respective cutter head and subsequent reinstallation of 
the same. Moreover, this brings about that the comminuting machine is out 
of service at such times, which leads to further disturbances of the 
operation, as well as resulting in a heavy work load of the respective 
machine. 
SUMMARY OF THE INVENTION 
Accordingly, it is an object of the present invention to provide a meat 
comminuting machine which avoids the disadvantages of the prior art. 
More particularly, it is an object of the present invention to provide a 
meat comminuting machine, in which a cutting unit can be so adjusted 
during idle running, that any unnecessary wear of the cutter blades 
provided on the cutter head is eliminated. 
In keeping with these objects and with others which will become apparent 
hereinafter, one feature of the present invention resides, briefly stated, 
in that a drive shaft which carries a cutter head provided with cutter 
blades is axially adjustable in dependence upon the respective loading of 
a motor, which drives the machine. In accordance with the present 
invention, in the event of a predetermined minimum loading of the driving 
motor the cutter blades of the cutter head tightly abut the opposite 
cutting surfaces of the neighboring perforated plate, while in the event 
of a reduction of this loading, the cutter blades of the cutter head are 
lifted from the perforated plate. 
For preventing any undesirable displacement of the driving shaft in an 
axial direction, it is further provided in accordance with another feature 
of the present invention, that when the axially displaceable driving shaft 
is in its extended position and in its retracted position it is 
arrestable, for example by means of an electronically controlled clamping 
device, which can be actuated pneumatically, hydraulically or 
electromagnetically. 
In accordance with an especially advantageous feature of the the present 
invention, a threaded sleeve is supported on the longitudinally 
displaceable driving shaft and abuts against the shaft in the axial 
direction via, for example a circular disk, a circular collar or the like. 
The threaded sleeve is rotatable by means of an adjusting or displacement 
motor, and its outer thread engages into an inner thread of a stationary 
bearing bush, which surrounds the threaded sleeve. The threaded sleeve is 
turnable relative to the stationary bearing bush, so that the threaded 
sleeve and the driving shaft together with the latter are imparted an 
axial displacement which leads to a respective lifting of the cutter 
blades of the cutter head from the oppositely located perforated plate for 
setting of the cutter blade with respect thereto. 
In connection with this, the above-mentioned threaded sleeve can also 
partially extend in an axial direction beyond the stationary bearing bush 
which surrounds it, and merge in this region into a cylindrical casing for 
tightly engaging a clamping ring of the above-mentioned clamping device. 
The clamping ring of the clamping device fixes in its clamping position 
the threaded sleeve and also the driving shaft which supports the cutter 
head in its respective position. In contrast, in an opening position the 
clamping ring allows rotation of the threaded sleeve by means of the 
adjusting motor and thereby an axial displacement of the driving shaft. 
In accordance with still a further feature of the present invention it is 
advantageous when the above-mentioned threaded sleeve is connected with a 
worm wheel or the like arranged coaxially with the threaded sleeve, while 
the worm wheel engages with a worm shaft driven by the adjusting motor. 
Moreover, so as to allow a required new adjustment of the cutter head 
relative to the associated perforated blade following the grinding of the 
cutter blades of the cutter head, the worm shaft of the adjusting motor is 
provided advantageously with a position-adjustable handle or the like for 
displacement of the driving shaft which supports the cutter head. 
The novel features of the present invention are set forth in particular in 
the appended claims. The invention itself, however, both as to its 
construction and method of operation, will be best understood from the 
following description of the preferred embodiments which is are 
illustrated in the appended drawings.

DESCRIPTION OF A PREFERRED EMBODIMENT 
A meat comminuting machine shown in a side view in FIG. 1 has a base 1 and 
a machine housing arranged on the base 1 and identified with the reference 
numeral 2. A bearing housing 3 is formed on the machine housing 2 and 
serves for receiving and supporting a driving shaft identified with the 
referenced numeral 4. The driving shaft 4 is driven in a rotation by an 
electric motor 6 via an elastic coupling 5. 
An inlet housing 8 is formed on the machine housing 2, and more 
particularly at a side which faces away from the electric motor 6. The 
inlet housing 8 is provided with a funnel 7. A cutting head identified 
with reference number 9 is arranged near the inlet housing 8 at a side 
which faces away from the electric motor 6. The driving shaft 4 and more 
particualarly its end identified with referenced numeral 10 extends 
through the cutting head 9. The cutting head 9 is covered by an outlet 
housing 11, which, in turn, is provided with a discharge opening 
identified with the reference numeral 12. 
The cutting head 9 has two stationary perforated plates 13 and 14 which are 
located one behind the other in a axial direction. The perforated plates 
are fixed by means of a ring holder 15, an abutting finger-ring 16, and a 
supporting ring 17 located between the perforated blade 13 and 14. The 
perforated plates 13 and 14 are associated with cutter heads identified 
with the reference numerals 18 and 19. Each cutter head is provided with a 
plurality of cutter blades 20. The cutter heads 18 and 19 are arranged on 
the free end 10 of the driving shaft 4 and arrested thereon. A shaft 
portion 21 which is located near the shaft end 10 and extends through the 
inlet housing 8, is covered by a sleeve 22 which rotates together with the 
driving shaft 4. 
As can be seen from FIG. 1, the machine housing 2 serves for supporting a 
stationary bearing bush 23 provided with an inner thread 24. A rotatable 
threaded sleeve 26 provided with an outer thread 25 is partially threaded 
into the bearing bush 23. A part 27 of the threaded sleeve 26, which 
projects beyond the stationary bearing bush 23, is cylindrical and abuts 
via a ring cover 28 against an outer surface of the driving shaft 4. A 
part 29 of the driving shaft 4 is supported in the threaded sleeve 23 by 
means of ball bearings 30. 
A worm wheel identified with reference numeral 31 is mounted on a part of 
the threaded bush 26 which is opposite to the part 27. A worm shaft 34 
engages with the worm wheel 31. The worm shaft 34 is driven in rotation by 
an adjusting motor 32 by chain wheels 33. 
As can be seen further from FIGS. 1 and 2, a clamping ring 35 tightly 
surrounds the cylindrical part 27. The clamping ring 35 is a part of a 
clamping device, and can be tightened or loosened by means of a clamping 
ring identified by the reference numeral 36 and an associated clamping nut 
37. The tightening and loosening of the clamping ring 35 is performed by a 
pneumatic cylinder-piston unit, which has a cylinder 38 and a piston rod 
39. The latter is articulately connected with a crank 40 arranged so that 
during a stroke of a piston 39, the crank 40 performs a turning movement 
in the direction of the arrow 41. Depending on the direction of rotation 
of the crank, a pulling or a releasing of the clamping nut 37 is 
performed, resulting in a respective tightening or release of the clamping 
ring 35. 
The meat comminuting machine in accordance with the present invention 
operates in the following manner: 
In the working position of the driving shaft 4 and the cutting heads 18 and 
9 arranged thereon, as is shown in FIG. 1, the piston 39 assumes its 
extended operative position in which the clamping nut 37 and clamping ring 
35 are tightened. The clamping ring 35 tightly engages along the 
cylindrical part 27, so that rotation of the threaded sleeve 26 is not 
possible. Thereby the driving shaft 4 is prevented from any axial 
displacement. In this working position of the driving shaft 4, the goods 
to be comminuted are supplied along the direction of the arrow 42 into th 
funnel 7, wherefrom they are transported in the direction of the arrow 43 
to the cutter heads 18 and 19 and the associated perforated plates 13 and 
14, and after cutting are withdrawn in direction of the arrow 44 through 
the discharge opening 12 of the outlet housing 11. 
When a further supply of the product to be cut takes place in direction of 
the arrow 42, the loading of the electric motor 6 is reduced. When the 
loading falls below a minimum loading, the piston rod 39 performs a stroke 
in direction of the arrow 45 by an electronic control, and thereby the 
crank 40 performs a turning movement in the direction of the arrow 41. 
This leads to a release of the clamping nut 37, and thereby also of the 
clamping ring 35 as well as to a release of the threaded sleeve 26. 
Subsequently the adjustment motor 32 is driven in rotation by an control 
electronic device. This rotation leads to a rotation of the threaded 
sleeve 26 via the worm shaft 34, and the worm wheel 31, and therefore 
leads to an axial displacement of the threaded sleeve 26 relative to the 
stationary bearing bush 23. As a result of the displacement of the 
threaded sleeve 26 in the direction of arrow 46, the driving shaft 4 
together with both cutter heads 18 and 19 is retracted, and thereby the 
cutter blades 20 are lifted from the cutting surfaces of the oppositely 
diposed perforated plates 13 and 14 as shown in FIG. 4. When this axial 
displacement of the driving shaft 4 ends, the piston rod 39 returns to its 
initial or operative position. Thereby the clamping ring 35 is again 
clamped, and therefore the threaded sleeve 26 and the driving shaft 4 
associated therewith are arrested. 
After the meat comminuting machine has been idling for a shorter or longer 
time, and again goods to be comminuted are supplied in the direction of 
the arrow 42 into the funnel 7, the loading of the electric motor 6 is 
again increased. As soon as the predetermined minimal loading of the 
electric motor 6 is exceeded, the electronic control again acts so as to 
release the clamping ring 35 as well as to turn the threaded sleeve 26. 
This leads to a displacement of the driving shaft 4 and the cutter heads 
18 and 19 arranged on it in a direction opposite to the direction of the 
arrow 46. The cutter blades 20 of both cutter heads 18 and 19 assume again 
the working position shown in FIG. 3, in which the blades tightly abut 
again the cutting surfaces associated with the perforated plates 13 and 
14. After the piston rod 39 is again returned to its inoperative position, 
the clamping ring 35 is again clamped, so that both the threaded sleeve 26 
and the driving shaft 4 with both cutter heads 18 and 19 are secured 
against any further axial displacement. 
To cope with a possible grinding of the cutter blades 20 of the cutter 
heads 18 and 19, the cutter blades 20 must be capable of being adjusted 
reliably and "with a feel" relative to the cutting surfaces of the 
neighboring perforated plates 13 and 14. For this purpose the worm wheel 
34 is provided with a handle which is identified with the reference 
numeral 47. The adjustment motor 32, the driving shaft 4, and thereby both 
cutter heads can be axially displaced in a manual mode by the handle 47, 
independently of the adjusting motor 32. 
The invention is not limited to the details shown since various medications 
and structural changes are possible without departing in any way from the 
scope of the present invention. 
What is intended to be protected by Letters Patent is set forth in the 
appended claims.