FI115983B - Arrangement in connection with the quick release chamber of the calender, especially the multi-nip calender - Google Patents

Description

The invention relates to an arrangement according to the preamble of claim 1. The invention relates to an arrangement according to the preamble of claim 1.

Of the types of calendars marketed by the TwinLine, such as the supercalender or the applicant's trademark Opti-Load, the roll of a multi-roll calender comprises, as usual, a plurality of rolls arranged on top of a roll stack. The overlapping rolls 10 are in nip contact with each other and a calendered paper or board web or the like is arranged to pass through the nips between the rolls. The rollers are rotatably mounted on bearing housings, which in turn are normally secured to base members slidably mounted on vertical guides in the calender body. The base portions are suspended by means of retaining members on 15 vertical lifting spindles in the calender body, one of whose functions is thus to act as a guide rail for keeping the rollers in the correct position. The rollers are thus not rigidly attached to the calender body from their bearing housings, but allow the rolls to move vertically.

* · · «* * · 20 Roller bearing housings and auxiliary devices attached thereto, such as output rollers • · *; · · · The masses are quite large, for example in conventional supercalendars: '': the major drawback was that the masses in question caused nipple lines> ;; · distortion of the pressure distributions. As a result, in multi-nip calendars, • examples! This is why supercalenders began to use lightening devices, supported on 25 roller heel members and on the spindle nuts on the lifting spindles, to reduce distortion in the line pressure profile between the roller bearings and the auxiliary devices attached to them. One such solution has been previously presented e.g. U.S. Patent 4,901,637. The use of lightening devices is also known from conventional machine calendars 30, in which hydraulic lightening cylinders, in particular, seek to minimize the above-mentioned point effects of roller bearing housings and auxiliaries.

FI patent 107626 discloses a method for rapid opening of a calender, especially a super calender 5, and a hydraulic system for calender, especially a super calender, track. The object of this known method and hydraulic system has been to provide a method and system for opening the nipples of the track in a controlled and desirable manner in the instant opening, most preferably with the instant opening of the nipples simultaneously.

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In prior art applications, the multi-nip calender lightening cylinder quick release piston is disposed within the piston rod and the oil discharge chamber is controlled from the piston rod side by a hose. When the hose is broken, there is an uncontrolled (one-sided) quick opening, whereby the roll surfaces of the calender rolls 15 may have touched one another and been damaged.

Thus, one problem with prior art calendars, especially multi-nip calendering reduction cylinder openers, has been the failure of the quick release chamber oil drainage due to the fact that: to damage. The layout design of the hose connection of the quick release chamber on the shaft of the lightening cylinder has been difficult since the hose must be positioned to allow large * · · * * arm movement.

It is an object of the present invention to provide a waste treatment that eliminates or at least minimizes the above-described problems in the prior art * · »* '* * state of the multi-nip calender lightening cylinder quick release * t» i · opening chamber.

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In order to achieve the foregoing and further objects, the arrangement according to the invention is essentially characterized by what is stated in the characterizing part of claim 1.

According to the invention, the oil of the quick release chamber of the multi-nip calender lightening cylinder is led through the main piston and the quick-release piston into a channel located at the rear end of the cylinder. Preferably, in the context of the invention, the tube of the quick-opening chamber is sealed and imaged to pass through the piston and the quick-opening piston into the breather chamber, and is provided with at least one bore to provide λ-10 flow. This avoids the disadvantages of breaking external parts, such as uncontrolled quick opening and thus damage caused by possible contact with the roll surfaces.

In the arrangement according to the invention, the increase and decrease of pressure in the quick-opening chamber is normally open / closed as the piston moves, since the oil outlet pipe is of a through-type and is preferably provided with bores to provide an oil flow. The volume of the quick-opening chamber of the multi-nip calender lightening cylinder of the invention remains constant during the movements of the piston, so that no pressure variation occurs.

I '!: 20': The method and arrangement according to the invention also make it easier to •. V nip nail calender layout because the quick release chamber oil drain hose is located inside the shaft.

The invention will now be described in more detail in the accompanying drawing; ·; with reference to the figures, to which details the invention is not intended to be; · 'I narrowly limit myself.

'* Figure 1 schematically illustrates a roller cylinder according to one embodiment of the invention in a non-pressurized position.

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Figure 2 schematically shows the relief cylinder of Figure 1 in a pressurized position.

Fig. 3 schematically shows the relief cylinder 5 according to Figs. 1-2 in an intermediate position.

1-3 illustrate a relief cylinder generally denoted by reference numeral 50. While conventional hydraulic cylinders generally have two operating positions, e.g., a pressurized operating position and a non-pressurized neutral position, the relief cylinder 10 has a third operating position in addition to these two positions. , between these two positions, to which position the relief cylinder can be stopped without complicated control circuits. The relief cylinder 50 comprises a cylinder member 51 having a piston 52 normally disposed axially movable therein. The body 50 of the cylinder member 51 is provided with a lower chamber tube 53 and an upper 15 chamber tube 54 through which the lower and upper chambers of the cylinder member 51 are connected. A large diameter through-hole is formed in the piston 52 and the shaft of the piston 52 in which the quick-opening piston 57 is disposed. Connected to the quick-opening chamber 56 is a closed-ended tube 58 passing through: a piston rod and a quick-release piston and a relief cylinder 51. Because the pipe * 1 ·: 20 58 is closed, no oil can enter the vent chamber 61. The sealed tube 58 of the quick-opening chamber 56 is provided with a bore 59 to provide an oil flow. The oil volume of the quick-release chamber 56 remains constant with the movements of the piston 52 · ;;; because the tube 58 moves at the same time during the movements of the main piston 52. The lightweight • · * 1 '1' nozzle filter has a vent chamber 61 25 at the end of the quick-opening chamber 56 and a vent chamber 62 which has air and a vent chamber 61! 58 moves during head piston movements. The drainage of the quick-opening chamber 56 is * · 1 traced through the main piston 52 and the quick-opening piston 57 to the rear end of the cylinder '1 in the passage 65. In the positions of Figures 1 and 2, the quick-opening chamber' '; The piston 57 of the 1 'moves with the main piston 52. The tube 58 protrudes into the chamber 61 as the main piston 52 moves inward.

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In Figure 1, the relief cylinder 50 is depicted in a non-pressurized state with the piston 52 depressed on the bottom of the cylinder member 51 by an external load acting on the piston 52. The situation of Fig. 1 may correspond to a service position in which all pressures are removed from the relief cylinders.

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Figure 2 illustrates a relief cylinder 50 in its first working position, which when applied to the calender corresponds to the calender running position where the calender nipples are closed. Figure 3 illustrates a quick-opening situation where the piston 57 of the quick-opening chamber is located at one end of a large-diameter opening made in the main piston 52.

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The invention has been described above only with reference to an exemplary embodiment thereof, the details of which, however, are not intended to be narrowly limited.

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Claims (4)

115963 An arrangement in connection with a calender, in particular a multi-nip calender quick release chamber, which calender comprises relief cylinders 5 (50), which relief cylinder comprises a cylinder part (51), a piston (52) movable therewith, and piston (57) of the opening chamber, characterized in that the drain (58) of the quick-opening chamber (56) is tracked through a piston (52) and a channel (65) located at the rear end of the cylinder. Arrangement according to Claim 1, characterized in that the tube (58) of the quick-opening chamber (56) is closed, whereby no oil can enter the venting chamber (61) and that the tube (58) is provided with at least one bore (59). to provide an oil flow to the quick-opening chamber (56) to maintain a constant oil volume. • i · • · • · t I 11Γ Ο Γ 7 7 I ί o y c o