Drive Unit for the Reel-Up of a Paper Machine or Paper Finishing Machine

The invention concerns a drive unit for the reel-up, either an unwinder or a winder, of a paper machine or paper finishing machine as well as a hydraulic operating system for the drive unit.

In unwinding and winding of a paper web, the paper web roll is placed in a bearing cradle. The device that rotates the web is coupled to a coupling connected to the end of the center drum of the paper web roll. In the prior-art solutions, said coupling is carried out by means of various cumbersome lever mechanisms. Thus, the engagement or disengagement of the reel-up is a time-consuming working step.

The object of the invention is to overcome the drawback mentioned above and to provide a drive unit of an entirely novel type for a center-wind reel-up of a paper machine, wherein the coupling of the driving shaft of the drive unit with the center drum of the paper roll takes place automatically and rapidly. A further object of the invention is a hydraulic operating system for the drive unit of the center-wide reel-up, by whose means, besides the lubrication of the bearing points in the system, also the stopping of the system in a braking situation is carried out.

The object of the invention has been achieved by means of a solution comprising equipment wherein the coupling between the driving shaft and the center drum of the paper roll has been accomplished by means of a cylinder device.

The drive unit in accordance with the invention for the reel-up of a paper machine or paper finishing machine is mainly characterized in that in its interior the shaft comprises a transfer shaft rotated along with the shaft, said transfer shaft being fitted to be displaceable on a coupling and uncoupling process in the direction of the central axis of the shaft by means of a cylinder device, whereby, when the transfer shaft is displaced towards the counter-coupling half of the central drum of the paper web roll, the coupling half attached to the end of the transfer shaft is displaced into engagement with the counter-coupling half.

The hydraulic operating system in accordance with the invention for a drive unit of a reel-up of a paper machine or paper finishing machine is mainly characterized in that the system comprises a hydraulic brake which stops the rotation of the shaft and which is fitted to be operable in braking situations by means of the pressure produced by the hydraulic pump by means of which said hydraulic pump the operating pressure is also supplied for the cylinder device as is the lubricant for the lubrication of the bearings in the gearbox.

The commonest embodiment of the invention consists of an arrangement of equipment wherein the rotating motor is coupled directly to the shaft or wherein the rotating motor is coupled to the shaft by means of a V-belt, cogged belt, or any other member that transfers the movement of rotation, said shaft being further coupled with the transfer shaft and, by means of the coupling part connected to said transfer shaft, with the counter-coupling piece on the central drum of the paper roll.

The invention will be described in the following with reference to a preferred embodiment of the invention illustrated in the figures in the accompanying drawings, the invention being, however, not confined to said embodiment alone.

FIG. 1A is a schematical illustration of principle of a drive unit in accordance with the invention.

FIG. 1B is a sectional view taken along the line I--I in FIG. 1A. What is shown is the cradle of the paper roll, into which the paper roll is mounted for coupling by means of the drive unit.

FIG. 2A is a partly sectional top view of a drive unit in accordance with the invention for the reel-up of a paper machine or paper finishing machine.

FIG. 2B is a more detailed illustration of the journalling of the end of the transfer shaft.

FIG. 2C is an illustration of the transfer shaft taken along line A--A of FIG. 2B.

FIG. 3 shows the drive unit shown in FIG. 2A as seen in the direction of the arrow K.sub.1 in FIG. 2A.

FIG. 4 shows the drive unit seen in the direction of the arrow K.sub.2 in FIG. 3.

FIG. 5 is a schematical illustration of a hydraulic operating system in accordance with the invention for the drive unit.

FIG. 1A is a schematical illustration of a drive unit in accordance with the invention for the reel-up of a paper machine or paper finishing machine. The paper roll P is mounted in bearing cradles K. As is shown in FIG. 1A, the output shaft of the gearbox V is coupled with the fastening members at the end of the central drum of the paper roll (arrow L.sub.1). The rotating drive is passed from the motor M through the brake J to the input shaft of the gearbox V and transferred further inside the gearbox from a smaller cogwheel to a larger cogwheel and then further to the output shaft of the gearbox, the coupling fitted on said output shaft being displaced by a cylinder device S in accordance with the invention.

FIG. 1B is a sectional view taken along the line I--I in FIG. 1A. From the figure it is seen that the bearing cradle K consists of a crescent-shaped bearing housing opening upwards, whereby the paper web roll P can be lowered freely onto the bearings.

FIG. 2A is a partly sectional top view of a preferred embodiment of a drive unit 10 in accordance with the invention for a center-wind reel-up of a paper machine or paper finishing machine. The motor 11, which is advantageously an electric motor, rotates the shaft 13 by means of a toothed coupling, said shaft 13 being attached to the toothed coupling 12 by means of a key 14. The motor 11 is coupled with the other end of the toothed coupling advantageously by means of a toothed connection, an inner bushing attached to the output shaft of the motor 11 being coupled with an inner toothing in the toothed coupling 12.

The shaft 13 is rotated further on the bearings 16 in the bearing housing 15, and the shaft 13 comprises a cogwheel 17 which is functionally connected with a driven larger cogwheel 18. The shaft 19 of the cogwheel 18 is mounted so as to revolve on bearing means 20 in the bearing housing 15.

Inside the shaft 19 there is a transfer shaft 21, with which the cylinder device 22 is coupled by its piston rod 22a. The transfer shaft 21 is passed through the central bore 19a in the shaft 19, and at its outer end it comprises a coupling half 23a, which is connected to a coupling half 23b placed on the central drum of the paper web roll in a coupling operation.

The coupling half 23a is attached to the transfer shaft 21 by means of a nut 24. Between the coupling half 23 and the nut 24 there is a lock washer 25.

The inner bushing 27 is attached to the outer face of the shaft 19 by means of a key 26. The inner bushing 27 comprises an outside toothing 28, which is jointly operative with the inside toothing 30 of the outer bushing 29. The outer bushing 29 is attached by its end in a fixed position on the coupling half 23a. The toothings 30 and 28 are fitted, as is indicated by the arrows L.sub.2, as gliding relative to one another in a coupling process.

The end of the transfer shaft 21 that is placed next to the cylinder 22 is attached revolvingly by the bearing housing 31 to its bearing means 32.

Thus, the inner transfer shaft 21 revolves at the same angular velocity as the shaft 19. However, the piston rod 22a in the cylinder device 22 must not revolve, and this is ensured by means of a key arrangement 33.

FIG. 2B is a more detailed illustration of the journalling of the transfer shaft 21.

The bearing housing 31 is fitted as gliding in a guide bushing 34 inside the bearing housing 15. Said gliding movement is illustrated by the arrows L.sub.2 in FIG. 2A. The bearing housing 31 comprises a body portion 31a proper and a related projecting projection end 31b of the bearing housing, said projection end being attached to the end of the piston rod 22a of the cylinder device 22 by means of a screw arrangement. Revolving of the bearing housing 31 is prevented by means of a key arrangement. The bearing housing 31 is provided with a groove (not shown), which runs on a key which has been bolted to the guide bushing 34. In this way, revolving movement is prevented, but longitudinal movement is permitted.

Thus, on a coupling process an extension of the output shaft 19 of the gearbox is permitted by means of the transfer shaft arrangement as the cylinder device 22 displaces the transfer shaft 21 during a process of uncoupling and coupling.

FIG. 3 shows a drive unit in accordance with the invention seen in the direction of the arrow K.sub.1 in FIG. 2A. As is shown in FIG. 3, the drive unit comprises upper brake shoes 35a and 35b and lower brake shoes 36a and 36b. Each brake shoe comprises four hydraulic piston devices. The brake shoes 35a and 36a are fitted to operate a brake disk 37a, and the brake shoes 35b and 36b are fitted to operate a brake disk 37b. The brake disks 37a and 37b are fixed permanently to the outer face of the toothed coupling 12. The brake shoes may be entirely conventional hydraulic brake devices, wherein the hydraulic piston is fitted, by means of hydraulic pressure, to press the brake pad against the brake disk 37a, 37b. The brakes shoes 35a . . . 36b are fixed to a brake stand 38. The figure does not show the drawing of the hydraulic piping to the piston devices that operate the brake pads of the brake shoes.

FIG. 4 shows a drive unit in accordance with the invention for a center-wind reel-up of a paper machine or paper finishing machine seen in the direction of the arrow K.sub.2 in FIG. 3. The figure shows the symmetric locations of the brake cylinders of the upper brake shoe and the lower brake shoe relative to the center line of the shaft 13 to be stopped. The drawing of the hydraulic piping to the piston devices of the brake shoes is not shown separately in the figure.

The commonest embodiment of the invention (not shown in the figures) consists merely of a arrangement of equipment wherein the rotating motor 11 is coupled directly to the shaft 19 or wherein the rotating motor 11 is coupled to the shaft 19 by means of a V-belt, cogged belt, or any other member that transfers the movement or rotation, said shaft 19 being further coupled with the transfer shaft 21 and, by means of the coupling part 23a connected to said transfer shaft 21, with the counter-coupling piece on the central drum of the paper roll. In this commonest embodiment the arrangement of equipment between the transfer shaft 21 and the shaft 19 is entirely similar to that in the particular embodiment of the invention shown in FIGS. 2A and 2B.

FIG. 5 is a schematical illustration of a hydraulic operating system for a drive unit in accordance with the invention for a center-wind-reel-up of a paper machine or paper finishing machine. The brake fitted on the rapid shaft of the drive unit stops the mechanism. The brake receives the necessary hydraulic fluid pressure from the lubrication unit, which is constructed in such a way that, in a braking situation, the unit is capable of providing the necessary pressure of 45 bars. In normal operation, the pressure is 10 bars. As is shown in FIG. 5, the motor M rotates the hydraulic pump 39, which supplies the pressurized hydraulic fluid and transfers it along the duct 40 to the branching point 41 and further to the electrically controlled twin-block direction valve 42. From the directional valve 42 a pressure line 43 passes to the hydraulic cylinder 22 and an exhaust line from the cylinder 22 through the valve 42 further to the tank T. From the branching point 41 a line 44 passes further to the lubrication of the bearings. The line 44 includes a pre-controlled pressure reduction valve 45. Further, from the branching point 41, a line 46 passes to the twin-block directional valve 47. The block 47 in the valve is on when no electric control is passed to the valve 47. In such a case the pressurized medium is passed from the line 46 to the line 48 and further to the hydraulic brake 34. When the valve block 47b is switched on while the control spindle is activated by means of a voltage supplied along the electric pre-control line 49, the line 46 is blocked, and the hydraulic pressure is not passed to the hydraulic brake 34. In such a case the hydraulic circuit 48 of the brake 34 communicates through the block 47b with the return line 50.

According to the invention, when the pre-controlled pressure reduction valve 45 is acted upon by means of electric control, the relief valve is opened and thereby a lower operating pressure is provided for situations of normal operation. In normal operation, the pressure in the system is about 10 bars. When electric pre-control is not passed to the valve 45, the valve is controlled so that the pressure reduction valve chokes the flow and produces a higher pressure for the system, the attained pressure and the necessary braking pressure being about 45 bars. According to the invention, the hydraulic cylinder and the other devices are fitted such that they endure said braking pressure of 45 bars.