Flat combing machine

The "cleaning-out" capability of a flat combing machine is increased by decreasing the distance between the jaw of the tong of the flat comber and the points of the opposed rows of needles on the round comber to a minimum distance and keeping this minimum distance constant. The needles are arranged on the round comber such that the radius of the needle points of the rows of needles lying side by side to the pivot of the round comber decreases, then increases, counter to the direction of rotation of the round comber. The tong is suspended by a pendulum and the distance between the pivot of the pendulum and the axis of the round comber is less than the sum of the maximum radius needle points to the pivot of the round comber, plus the minimum distance from the jaw of the tong to the needle points, plus the radius of the jaw of the tong to the pivot of the pendulum.

BACKGROUND OF THE INVENTION 
The invention relates to the field of pretreatment of fibers and deals with 
a flat combing machine termed a flat comber, whereby the rows of needles 
are firmly and rigidly arranged on the round or circular comber and, 
whereby the tong or nippers, driven via a crankdrive mechanism, is mounted 
to a suspended pendulum. 
CHARACTERISTICS OF THE KNOWN TECHNICAL SOLUTIONS 
In the case of a known flat combing machine of the aforementioned type (as 
described in the Prospectus of the Cotton Combing Machine Model 1532 of 
the Kombinat VEB Spinnereimaschinenbau Karl-Marx-Stadt and as disclosed in 
DD-Pat. Nos. 80 640 and 125 422), the points of the needles of the 
adjoining rows of needles are arranged concentrically to the center of the 
round or circular comber. If the flat combing machine is working, the 
points of the needles move along an orbit which is concentric to the pivot 
point of the round comber, and the jaw of the tong (nippers) moves along 
an orbit which is concentric to the pivot point of the tong. During the 
main combing procedure, the tong (nippers) carries out a retrograde 
motion. During this process, the distance between the jaw of the tong and 
the points of the needles of the opposite row of needles changes, whereby 
the distance at the first row of needles is the maximum distance, which 
decreases thereafter, reaches a minimum distance between the eighth and 
tenth row of needles, and increases thereafter up to the fourteenth row of 
needles, as it is illustrated by the dotted line in the diagram of FIG. 1. 
Ordinarily, depending upon the setting or adjustment, the minimum distance 
between the jaw of the tong (nippers) and the points of the needles 
amounts to 0.3 to 0.5 mm. The disadvantage here is that the "cleaning-out" 
degree is decreased, if the distance between the jaw of the tong and the 
points of the opposite-located row of needles is larger than the minimum 
distance. 
OBJECT OF THE INVENTION 
It is the object of the invention to increase the "cleaning-out" degree. 
SUMMARY OF THE INVENTION 
The technical task which is being solved through the invention consists of 
decreasing the distance between the jaw of the tong and the points of the 
respective opposite-located row of needles and of keeping it almost 
constant in the range of the fine needles after the minimum value has been 
reached. 
According to the invention, this is achieved in the following manner: the 
distance between the pivot of the round (circular) comber and the pivot of 
the suspended pendulum is smaller than the sum of the maximum radius of 
the needle points to the pivot of the round comber, the minimum distance 
between the jaw of the tong and the points of the needles and the radius 
of the jaw of the tong to the pivot of the suspended pendulum. At the same 
time, the radius of the needle points to the pivot of the round (circular) 
comber of the rows of needles lying side by side must decrease at first, 
counter to the direction of rotation of the round comber, and increase 
afterwards. 
A preferred embodiment is one whereby the points of the needles of the rows 
of needles lying side by side are located on a radius which is larger than 
the maximum radius of the needle points to the pivot of the round comber. 
Another embodiment is one whereby a rotating shaft or rocker arm is located 
ahead of the suspended pendulum carrying the lower tong and the link or 
joint between this rotating shaft and the appertaining coupler is fastened 
in a curved elongated hole or slot and whereby the center of the radius of 
the curved elongated hole (slot) in the rear end position of the tong is 
located in the opposite-located pivot of the coupler. This assures that 
the rear end position of the tong (nippers) remains constant when the 
"tear-off" distance is adjusted.

The round comber 1 is fastened on the round comber shaft 2 (FIG. 2). 
Arranged on the round comber 1, in a manner not shown here, are the rows 
of needles 3 with the needles 4. The radius 5 of the points of the needles 
4 to the pivot 6 of the round comber 1 of the needle rows 3 lying side by 
side decreases at first, counter to the direction of rotation 7 of the 
round comber 1, and increases afterwards. 
In the first and fourteenth row 3, counter to the direction of rotation 7, 
the radius 5 reaches its maximum value and, approximately between the 
eighth to the tenth row 3, its minimum value. Located above the round 
(circular) comber 1 is the tong (nippers) 8 with its jaw 9 which consists 
of the lower tong 10 and the upper tong 11. The lower tong 10 is fastened 
to the driven rotating shaft (rocker arm) designed in the form of a 
suspended pendulum 12 which can be rotated around the tong axis 13. The 
suspended pendulum 12 receives its impulse or movement via coupler 14 
which is connected with the suspended pendulum 12 with the pipe or tube 
15. The jaw 9 of the tong 8 swings to the radius 16 around the pivot 17 of 
the suspended pendulum 12. The upper tong 11 is fastened to the rotating 
shaft 18 which can be rotated around the pipe (tube) 15. The drive (not 
shown here) causing the lifting and lowering of the upper tong 11, engages 
at the joint 19 of the rotating shaft 18. Behind the round comber 1 and 
the tong 8, the pair of " tear-off" (web breaking) rollers 20 is attached 
in the vicinity of the round comber 1. The round comber 1 and the tong 8 
are arranged in such a manner that the distance 21 between the pivot 6 of 
the round comber 1 and the pivot 17 of the suspended pendulum 12 is 
smaller than the sum of the maximum radius 5 of the needle points 4 to the 
pivot 6 of the round comber 1, the minimum distance 22 between the jaw 9 
of the tong 8 and the points of the needles 4, and the radius 16 of the 
jaw 9 of the tong 8 to the pivot 17 of the suspended pendulum 12. 
Ordinarily, depending upon the setting (adjustment), the minimum distance 
22 amounts to 0.3 to 0.5 mm, when the jaw 9 of the tong 8 is located 
opposite the eighth to the tenth row of needles 3 of the round comber 1. 
In order to adjust the minimum distance 22, the suspended pendulum 12 
consists of two parts and is provided with the adjusting screw 23 and the 
tightening screws 24. 
If the flat combing machine is in operation, the round comber 1 moves in 
the direction of rotation 7. During the main combing process, the tong 8 
carries out a retrograde motion in the direction 25. Hereby, the distance 
22 between the jaw 9 of the tong 8 and the needle points 4 of the 
respective opposite-located needle row 3 undergoes a change. This change 
of the distance 22 is illustrated by the solid line in the diagram 
according to FIG. 1. At the first row of needles 3, the distance reaches a 
maximum, decreases thereafter, reaches a minimum distance between the 
eighth and the tenth row of needles 3 and remains almost constant up to 
the fourteenth row of needles 3. The reduction of the distance 22, as 
compared to the aforementioned known technical solution, as shown by the 
dotted line, can also be seen in the diagram according to FIG. 1. 
In another type of embodiment (FIG. 3), the points of the needles 4 of the 
needle rows 3, lying side by side, are located at a radius 26 which is 
larger than the maximum radius 5 of the needle points 4 to the pivot 6 of 
the round comber 1. 
The embodiment according to FIG. 4 shows a crankdrive mechanism for the 
propulsion of the tong 8. The crankdrive mechanism is composed of a 
crossed oscillating or swinging crank guide which, in turn, consists of 
the crank 27, the slide ring 28 and the rotating shaft (rocker arm) 29, 
and two double rockers, whereby the first double rocker consists of the 
rotating shafts 30, 32 and the coupler 31, and the second double rocker 
consists of the rotating shaft 33, the coupler 14 and the driven rotating 
shaft which is designed in the form of a suspended pendulum 12. Whereas 
the crank 27 is fastened to the axle of the round comber 2 and the 
suspended pendulum 12 is swingable around the tong axis 13, the rotating 
shafts 29, 30--which are rigidly (solidly) comnected with each other--are 
swingable around the axle 34 and the rotating shafts 32, 33--which are 
also rigidly connected with each other--are swingable around the lower 
tong axle 35. At the rotating shaft 32, which is located in front (ahead) 
of the suspended pendulum 12 that carries the lower tong 10, the joint 36 
is fastened in a curve elongated hole (slot) 37 between this rotating 
shaft 32 and the appertaining coupler 31, whereby the center of the radius 
38 of the curved elongated hole in the rear end position of the tong 8 is 
located in the opposite-located pivot of the coupler 31. The adjustment 
(setting) of the rear end position of the tong 8 (FIG. 5, tong 8 in solid 
line) is carried out in dependency of the largest fiber length which is to 
be worked on. After the adjustment of the rear end position of the tong 8, 
the position of the needle points 4 of the needle rows 3 is fixed, whereby 
in the case of the embodiment according to FIG. 3 the radius 26 is 
established. The "tear-off" distance 40 between the pair of "tear-off" 
(web breaking) rollers 20 and the tong 8 in its front end position (FIG. 
5, tong 8 in dotted line) is being adjusted by moving the joint 36 in the 
curved elongated hole (slot) 37, depending upon the degree or extent of 
the combing-out. The "tear-off" distance 40 (FIG. 5) reaches the minimum 
value when the joint 36 in the curved elongated hole is in the position 41 
(FIG. 4) and the maximum value when the joint 36 is in the position 42. 
The constant rear end position of the tong 8 makes it possible that the 
minimum distance 22 (FIG. 2) reached between the eighth and tenth row of 
needles 3 remains almost constant up to the fourteenth needle row 3, even 
if the "tear-off" distance 40 (FIG. 5) is shifted (adjusted); all this 
without having to change the position of the needle points 4 of the needle 
rows 3 or, additionally, the stroke of the tong 8.