GB2197888A

GB2197888A - Drum napping machine

Info

Publication number: GB2197888A
Application number: GB08727667A
Authority: GB
Inventors: Wilhelm Busch; Romuald Vaisnys; Albert Vroomen
Original assignee: Sucker & Franz Mueller GmbH
Current assignee: Sucker & Franz Mueller GmbH
Priority date: 1986-11-27
Filing date: 1987-11-26
Publication date: 1988-06-02
Anticipated expiration: 2007-11-26
Also published as: DE3640575A1; FR2607525A1; FR2607525B1; GB8727667D0; GB2197888B; JPS63145472A; DE3640575C2; ES2005665A6; IT8722361A0; IT1222957B

Abstract

A drum napping machine for napping webs and comprises napping rollers 4 and a plurality of belts 18-23 fixed with an initial tension between respective fixed points 16 and tensioning points 17 and on a belt carrier adapted to be driven in relation to the drum 1. The belts 18-23 are arranged to drive the rollers 4 the ends, or belt pulleys 24 of which run on the belt. A traction device 27 is associated with each tensioning point 17 for regulating the initial belt tension to an adjustable value in order that the napping effect can be reduced or enhanced. Adjustment of tension on each belt 18-23 is possible by rotating a tensioning shaft at which the point 17 is disposed. The device 27 includes a pneumatically driven piston 30 having a piston rod 31 which is connected to a chain 28 which in turn cooperates with a sprocket 26 of the tensioning shaft. The adjusted initial belt tension can be transmitted to a remote indicator. <IMAGE>

Description

Drum napping machine.

The invention relates to a drum napping machine with a set of napping rollers, comprising napping and/or counterstroke napping rollers and with a plurality of belts mounted with initial tension between respective fixed points and tensioning points on a belt carrier, particularly a toothed wheel, adapted to be driven in relation to the drum, on which belts - during operation - run the ends of the napping and/or counterstroke napping rollers, the belts being adjacently disposed and being offset in the direction of the drum periphery by less than their length.

Drum napping machines can be equipped with sets of napping rollers and drives for ordinary napping and counterstroke napping operation, semi-felting, full felting, purely napping work or purely counterstroke napping work. In the normal construction of a drum or card napping machine as a napping/counterstroke napping machine, the napping drum is moved at a constant speed in the direction of movement of the web of material which is to be napped. The actual napping rollers then run against the direction of feed of the web of material.

In this set of napping rollers on the periphery of the drum, one napping roller always alternates with one counterstroke napping roller. According to the rotary speed of the individual napping rollers, so the napping effect is correspondingly influenced.

The conventional napping roller drive is provided by V-belts running on the belt pulleys which are mounted at the ends of the napping rollers and which are fixed to a belt carrier adapted to be variably driven in relation to the drum. Usually, the belt carrier is'a toothed wheel which is driven by a pinion. The locations at which the V-belts are fixed on the toothed wheel are, for example, staggered by 600 on the belt carrier so that in addition to the variability of rotation of the belt sets, a satisfactory pull-through action is assured. The reciprocaloffset of the belts ensures that the individual roller end which is to be driven is always in contact with at least two belts at the same time, the fixed and tensioning points of the said belt being offset in relation to each other in the peripheral direction of the belt carrier.

Where such a drum napping machine is concerned which has napping rollers driven via belts and roller ends, where the belts are mounted with a fixed tension, the initial belt tension diminishes from roller to roller in the direction of loading, even if the belt has the same initial tension over its entire length when the machine is inoperative and relieved of loading. If the torques exerted on the napping rollers and the energy transmitted by the napping rollers is required to be increased or reduced, then the belt tension can be correspondingly increased or reduced in order to vary the slip between belt and belt pulley. In the case of the known machines, the belt tension can only be altered by hand.

For such a readjustment of the initial belt tension, the machine has to be stopped because, when the machine is operating, the belt carrier is rotated in relation to the rotating drum. The individual belt must therefore be so adjusted while the machine is stationary, in other words while it is static, that during operation, in other words under dynamic conditions, the desired force can be transmitted from the belt carrier to the individual napping roller. In particular, under such conditions, belt stretch can only be inadequately compensated.

In practice , napping machines are available of which the sets of napping rollers are directly driven outside the drum by means of belts looped around the (napping or counterstroke/napping) roller ends of the drum as a xihole. To regulate the belt tension and thus the torque which is transmitted to the set of napping rollers, the initial tension of the relevant belt is preset andif necessary - also altered during operation by means of a traction means. An essential disadvantage of such a napping roller drive resides in that the transmitted torque decreases in the direction of loading from roller to roller so that the napping force exerted on the web of material to be treated likewise diminishes from roller to roller so that finally only a part of the drum periphery exerts the desired napping effect.

The napping result of a napping/counterstroke napping roller napping machine is dependent upon the speed of the web of material and upon the belt speed, that is to say, in the case of a drum napping machine of the type mentioned at the outset, it depends on the speed of the belt carrier. Since the transmission of force from the belt to the drive pulley at the roller end of the relevant napping roller also depends on slip between belt and drive pulley, so the torque exerted on the individual napping roller can also be varied by presetting the slip. The slip depends inter alia on the initial tension of the belt.

Therefore, if one can succeeed in varying the initial tension of the individual belt which is rigidly connected to the belt carrier, then the operating point of the machine which is defined by the speed of the web of material and the torque exerted on the napping rollers can be adjusted to whatever is the most favourable value, even while the machine is running.

For a drum napping machine of the type mentioned at the outset, the invention is based on the problem of providing a regulable napping roller drive in which the statically predetermined initial belt tension also remains unaltered or can be adjusted during operation in the event of a load dependent belt elongation; furthermore, it is intended that the initial belt tension be capable of being increased or reduced optionally by remote control so that the napping energy transmitted by the napping rollers can be correspondingly varied. The solution according to the invention resides in that traction means are associated with the tensioning point of each belt for regulating the initial belt tension to an adjustable value.

According to the invention, the initial tension in the belt is kept constant if the tractive force of the traction means maintains the initial belt tension at the tensioning point constantly at a present value and if there is automatic compensation for belt elongation. If the torque levels transmitted to the drive pulleys of the napping rollers by the individual belts which are moved together with their belt carriers, and thus the energy transmitted by the relevant napping roller required to be increased or decreased, then according to the invention it is sufficient to increase or reduce the belt tension during operation and by means of the traction means.Therefore, along with automatic regulation of the belt tension to a predetermined fixed value, there is the opportunity, while the machine is running, for increasing or reducing the belt tension as a value superimposed on the fixed value.

According to a further feature of the invention, for tensioning or adjusting the tension of the belt, traction means are provided with facility for remote indication of the tensioning force actually adjusted. In principle, any desired remotely controllable drive means may be used for the purpose, e.g. a motor, a hydraulic cylinder or a pneumatic cylinder. What is important is that there should also be the possibility of remotely indicating the actual belt tension to whomsoever is transmitting the command.

Since the belt carrier, which is generally constructed as a toothed wheel, is adapted for rotation relative to the main shaft of the drum, and has a separate drive, and since the drum likevise rotates during operation, it is according to a fur'ther feature of the invention preferred to construct the traction means as a pneumatic cylinder, of which the compressed air supply line extends through a rotary entrance into the longitudinally bored out main shaft of the drum and thence via a rotary bushing in a radial direction to the belt carrier.

A particular advantage of using air pressure resides in the fact that if there is a leakage in the supply line or in the compressed air cylinder - otherwise than w h e n hydraulics are used there is no danger of the machine or the veb of material being handled being dirtied. An essential advantage of the pneumatic construction also resides in the fact that there is no need for a separate line for remote indication of the adjusted belt tension, because t; air pressure itself represents such a measuring agent. For example, in contrast to the situation w h e n an electric motor is used as the traction means, therefore, there is no need for a separate remote indicating arrangement.

While a napping machine is operating, it is desirable that the operating data, i.e. the napping energy and the peripheral speed of the drum, w h e n a web of material is being handled, be adjusted to the optimum levels as promptly as possible, i.e. as far as possible without any loss. To this end, practice involves initially ascertaining the operating data for all types of material likely to be encountered which are then collected, for instance, in a table or in an electronic memory. If then an already stored type of material web has to be napped, the operator requires only to adjust the optimum operating data.known for that particular type.

Adjusting the operating data naturally includes also adjustment of the initial belt tension. In the case of earlier machines of the type mentioned at the outset, the initial belt tension must be measured and adjusted by hand for each individual belt while the machine is shut down. If the invention is applied, the operating data which affect the napping rollers can be variably preset by means of the traction means. If the traction means take the form of pneumatic cylinders, therefore, it is sufficient for the compressed air values associated with specific napping results to be registered as operating data and adjusted as required in order to obtain the optimum napping result with effect from the first metre of the web of material.

Details of the invention will now be explained hereinafter with reference to the accompanying diagrammatic drawings, in which: Fig. 1 shows a section parallel with the drum axis of a card napping machine showing details of the principle of napping roller and drum drive; Fig. 2 is a section taken on the line II-II in Fig. 1; Fig. 3 is an enlarged view of the tensioning point of a belt according to Fig. 1, and Fig. 4 shows a section parallel with the axis of the tension ing shaft according to Fig. 3.

Fig. 1 shows a drive part of a napping machine in a section taken substantially through the middle of the drum 1. The drum 1 consists essentially of a main shaft 2 and a plurality of napping rollers 4 mounted cylindrically about the main shaft 1 and adapted to rotate in bearing plates 3. The napping rollers 4 may be napping and/or counterstroke napping rollers. The drum 1 which has its main shaft 2 mounted in a stand 5 comprises a drum drive 6 having a motor 7 and gear mechanism 8, e.g. toothed gear mechanism, mounted on the stand 5.

Also fi-ied or rr on on the machine stand 5 stand 5 is a napping roller drive 9. The napping roller drive 9 consists, for example, of a motor 10 having a toothed gear mechanism 12 leading to a pinion 11 and which is mounted in the stand 5. During operation, the pinion 11 engages the toothed gear 13 of a central gear 15 mounted on the main shaft 2 and adapted to rotate in bearing 14.

Belts 18 to 23 are in each case mounted on the central gearwheel 15 between a fixed point 16 and a tensioning point 17 and with initial tension so that during operation the roller ends or belt pulleys 24 of the napping rollers 4 can run on the belts and so be caused to rotate (see also Fig. 2). In order to fix the individual belts 18 to 23 on the central gearwheel which serves as a belt carrier, clamping or rolling means are provided at the res pectin fixed point 16 and tensioning point 17.

In general, the individual belt 18 to 23 is rigidly clamped at the fixed point 16 and is so wound around a tensioning shaft 25 rotatably mounted in the central gearwheel 15 dt the tensioning point 17 according to Figs. 3 and 4 that increasing or reducing the belt tension is possible by rotating the tensioning shaft 25.

In the example of embodiment illustrated, there is mounted on the tensioning shazft a sprocket 26 which is connected to a traction means generally designated 27 (see Fig. 4). The traction means 27 may consist of a chain 28 and, adapted for movement in a pneumatic cylinder 29, a pneumatic piston 30 having a piston rod 31 which is connected to the chain 28. The construction of traction means 27 is such that it has room within @ space en- closed by the central gearwheel 15 and that the adjusted initial belt tension can easily be transmitted to a remote indicator.

In the embodiment illustrated, compressed air is used for actuating or operating the traction means. For this purpose, there is fitted, for instance, on the longitudinal end 32 of the main shaft 2 a sealed first rotary entrance 33 which makes it possible to connect a compressed air feedline 34 to a longitudinal bore 35 in the main shaft 2 which rotates during operation.

The rotary entrance 33 can likewise be mounted on the stand 5.

The connection between the compressed air supply line 34 and the pneumatic cylinder 29 to which the compressed air is applied requires in the embodiment shown a further rotary entrance or rotary transfer line in the contact area between main shaft 2 and central gearwheel 15. This second rotary entrance 36 leads directly or indirectly to a supply line 37 of the relevant pneumatic cylinder 29 and provided in the central gearwheel 15.

Since the pressure in the supply line 37 and in the pneumatic cylinder 29 as well as in the bore 35 and in the first rotary entrance 33 must be substantially the same everywhere, the air pressure measured at the first rotary entrance 33 can without any problem be so calibrated that it indicates the belt tension or the like. For this purpose, in the example of embodiment in question, there is inter alia a pressure gauge 38 provided at the inlet to the first rotary entrance 33.

In the example of embodiment shown in Figs. 1 and 2, six belts 18 to 23 are disposed around the periphery of the central gearwheel 15 which serves as a belt carrier, the belt being staggered by respective intervals of 600 and extending between a fixed point 16 and a tensioning point 17 and being at a specific initial tension. At the tensioning points or locations 17, the belt tension can be variable or adjustable to a fixed value by means of a traction means 27. The section according to Fig. 1 is such that the fixed point 16 of the belt is in the lower part of the drawing while the tensioning part 17 of the belt (Fig. 2) is in the upper part of the drawing.

Claims

claims:

1. Drum napping machine with a set of napping rollers comprising napping and/or counterstroke napping rollers and with a plurality of belts (18 to 23) mounted with initial tension between respective fixed points (16) and tensioning points (17) on a belt carrier, particularly a toothed wheel, adapted to be driven in relation to the drum (1), on which belts - during operation - run the ends of the napping and/or counterstroke napping rollers (4), the belts being adjacently disposed and being offset in the direction of the drum periphery by less than their length, characterised in that traction means (27) are associated with the tensioning point (17) of each belt (18 to 23) for regulating the initial belt tension to an adjustable value.

2. Napping machine according to Claim 1, characterised by traction means (27) with facility for remote indication of the tensioning force actually set.

3. Napping machine according to Claim 1 or 2, characterised in that one'end of the relevant belt (18 to 23) is at the tensioning point (17) wound onto a shaft (25) adapted to be actuated by means of a sprocket (26) with which the traction means is associated.

4. Napping machine according to one or more of Claims 1 to 3, characterised by energy supply and tensioning force remote indicating conductors which are passed through the main shaft (2) of the drum (1) and through the belt carrier which is rotatable in relation to the main shaft.

5. Napping machine according to Claim 4, characterised by rotary entrances (33, 36) of the conductors at the longitudinal end of the main shaft (2) or in the area of contact between main shaft (2) and belt carrier (15).

6. Napping machine according to one or more of Claims 1 to 5, characterised by the use of a pneumatic cylinder (29) as the traction means.

7. A drum napping machine, substantially as described herein with reference to and as illustrated by the accor.panying drawings.