JP5261008B2 - Method and apparatus for removing zero load on bearings - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for easing or wholly removing problems with zero load on a fiber web machine. <P>SOLUTION: In the method for easing zero load on a rotating machine mechanism 1 for the fiber web machine in relation to a supporting part, the machine mechanism 1 is subjected to loads Q1, Q2 in a load direction. According to this invention, a load F on the machine mechanism 1 is arranged, different from that in the load direction in a region where the zero load may be at least during work. A mantle, a supporting shaft 2, and a main bearing 3 of a rolling bearing type arranged on the shaft 2 belong to the rotating machine mechanism. The device is formed by load mechanisms 5-7 having at least one load on the machine mechanism 1, different from that in the load direction. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The object of the present invention is a method for removing the zero load of a bearing such as a roller bearing, a needle bearing, or a ball bearing for a rolling bearing comprising a stationary rolling mechanism, for example.

  An apparatus for implementing the method is also an object of the present invention.

  When manufacturing paper, cardboard, and other fibrous webs, variously between the rolls during manufacturing, especially for dehydration, for applying process substances, and for smoothing and polishing the product surface Different roll gaps apply. The strongest pressing force is generated during calendaring or dehydrating press. The roll gap load between each roll is adjusted by different types of actuators, and in some situations, the load facing the support bearing of the roll is virtually eliminated and the bearing reaches the so-called zero load range. As such, it is possible to compensate for the forces facing the roll. This means that the load on the bearing is such that the load facing the rolling mechanism of the bearing is too small to cause rolling contact and the bearing starts to slide. Zero load is detrimental to the bearing. This is because sliding contact wears the rolling mechanism of the bearing fairly quickly. Therefore, to eliminate the zero load problem, bearing manufacturers recommend a load that is 1-2% of the bearing capacity.

  In most cases, the danger of entering the zero load region occurs in the case of a calendar. The bearing load of the main roll of the calendar changes with the operating condition of the calendar. Adjustment of the linear pressure on the calendar affects the bearing load. When the force generated by the pressing force by the vertical roll mechanism and the roll gap force that lifts the roll from below are compensated, no load is generated on the bearing. Similarly, if the linear pressure on both sides is directed toward the roll, a situation can be created in which the roll gap force acting in various directions and the tensile force of the roll mass are compensated for each other. Rolling bearings require a certain load to prevent the bearing rollers or balls from rotating and sliding. In the zero load situation described above, such load criteria are not met.

  In the multi-roll calender, zero load is generated during the so-called partial roll gap operation, in which only two or three rolls work together. Problems also arise with soft calendars. To eliminate the zero load problem, the adjustment range for the linear pressure of the calendar is limited. For vertical soft calender and multi-roll calender models, the minimum load size recommended by the bearing manufacturer significantly reduces the available linear pressure range, especially for the matte paper type. The constrained operating range is typically 20.degree. Due to the zero load problem. . , 100 kN / m, which can be as much as 30% of the linear pressure range of partial roll gap operation of a multi-roll calendar. This is a serious problem if the process should work best within this range.

In order to remove or alleviate the zero load, the following measures are applied in particular in the prior art:
The roll mechanism can be tilted so that the lateral thrust component of the load produces the minimum load required for the bearing; a solution of this kind is described in WO 2006/051169 It is described in the issue pamphlet.
-Axial loading device for outer ring circumference-US Pat. No. 6,158,897.
-Bearing coating to deal with zero load situations.
-Prevention of calendar load in the zero load region.
-Generation of braking force on the bearing by the oil flowing through the bearing-U.S. Pat. No. 4,322,117.

  The assembly of tilted roll mechanisms in a vertical calendar model requires new planning for the entire roll mechanism and for the positioning of each device. This solution is therefore not suitable for applying at least with existing calendars. If you continue to adopt the vertical calendar model for other reasons, tilted assembly is not a good option. This is because such assembly leads to a costly roll displacement device. Attempts have also been made to use axial loading devices with soft calenders. This device does not completely solve the problem, especially in the case of two-row roller bearings of medium to high height. This is because this device only applies a load to one of the roller rings, and the load on the ring part parallel to this is further reduced. To alleviate the zero load region problem, bearing coating is an option. However, coating does not solve the problem entirely. In addition, the coating is costly and its suitability depends greatly on the lubrication conditions. Since the rolls are interchangeable, all rolls must be equipped with cost-intensive coated bearings.

  The object of the present invention is to create a method and apparatus for alleviating or eliminating the zero load problem in fiber web machines.

  The present invention relies on the shaft leading from the roll to the bearing of the fiber web machine being loaded in a radial direction different from the load direction.

  In one preferred embodiment of the invention, the loading direction is substantially horizontal. As a result, there is no load direction component that must be taken into account when calculating the linear pressure of the machine.

  In one preferred embodiment, the shaft leading to the bearing is loaded directly.

  Strictly speaking, what characterizes the method according to the invention is what is stated in the characterizing part of claim 1.

  What characterizes the device according to the invention is likewise the matters described in the characterizing part of claim 6.

  The present invention provides significant advantages.

  The present invention eliminates bearing damage caused by the zero load problem. The utilization of each device is improved and unpredictable production interruptions are reduced. The implementation of the device is simple and advantageous accordingly and can be applied to existing devices. In the most advantageous case, the device has no effect on the function of the calendar other than to remove the inconvenient limitation of the operating range. Without the limitation of the operating range, the machine operator can further optimize the production, for example to produce the highest quality. The advantage of this device lies in its simplicity and the resulting reduced space requirements. The device does not require a cooled sealed bearing bush for the roll shaft. The movement of the roll does not complicate the device. This is because the device is attached to the roll only when it is in operation when each roll is in a linear position. When the roll mechanism is opened, the device is immediately removed from the roll axis.

  Next, the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 shows a roll 1 with a shaft 2 at the end. The shaft 2 is attached to a bearing bush 3, and the bearing bush is attached to a load arm 4. The roll 1, the shaft 2, and the bearing bush 3 are movably supported by a load arm. The example of FIG. 1 may be a calendar roll that does not move much when activated, but moves at high speeds over a fairly long section, for example when the web breaks and opens the roll gap. In the load device according to the present invention, a load fork 5, a hydraulic cylinder 6 for driving the load fork 5, and a wear ring 7 are combined. In relation to the shaft 2, this load device is arranged so that the movement / load direction of the hydraulic cylinder 6 extends in the horizontal direction when the calendar is operated. In this example, the cylinder 6 is attached to the load arm 4 in the same direction by the holding portions 10 and 11. In this way, the direction of movement of the cylinder extends in the same direction as the load arm. The design of the load fork 5 can be seen more clearly in FIG. The load fork includes a Y-shaped fork main body 8, an arm portion of which is attached to the hydraulic cylinder 6, and a load wheel 9 that is supported by rolling is disposed at each end of the fork. There is a wear ring 7 at the position of the load fork 8 on the shaft 2 of the roll 1, and the load wheel is pressed against this wear ring. The load ring is set based on the surface pressure, and the roll replacement interval is sufficient for the service life of the load ring. This is because the ring is kept attached to the replaceable roll. The width of the load wheel and wear ring may be about 100 mm.

  In order not to generate a vertical load component acting on the roll gap load, the load direction should extend in the horizontal direction as accurately as possible. In that case, when calculating the roll gap load, it is not necessary to take into account the load that prevents zero load. However, with modern computing power, adding any standard load to the roll gap load calculation does not cause any difficulty.

In FIG. 2, the symbols Q ₁ and Q ₂ are attached to the roll gap load, and the symbol F is attached to a load that prevents zero load. Furthermore, naturally the roll mass acts on the roll gap force and the bearing force. Nevertheless, if the increased load force F extends in the horizontal direction or extends at an angle of 90 ° with respect to the vertical load, the calculation of the roll gap load can be left unchanged. Yes, and no intervention in the calendar function in this regard is necessary. The danger of a zero load situation generally occurs only in the case of a load in the vertical direction, but even in a load situation that is performed in a direction different from the vertical direction, the forces facing the bearing are zero load. Sometimes summed up in such a way that the situation occurs. The present invention can also be applied to such a case. Most advantageously, zero load compensation is provided for vertical load forces, but slight differences from this direction will also cause little change in roll gap load. For example, if the load that removes the zero load in the case of the vertical load is set within the range of 75-105 °, the ratio of the vertical component is considerably reduced, and it can even be overlooked when calculating the roll gap load. . The same applies to the load situation extending in a direction different from the vertical direction.

  The minimum load required by the bearing is applied to the roll 1 by means of a rolling-supported load wheel 9 that applies a load to the shaft 2 of the roll 1 along with the main bearing bush 3. Since this load is applied in a substantially horizontal direction, it does not need to be taken into account even when calculating the linear pressure on the calendar. The device can be manufactured for loads in other directions, in which case the load will be taken into account in the linear pressure calculation. The horizontal force does not cause a significant shape change in the roll gap and therefore does not affect the transition of the calendar linear pressure. The apparatus is preferably switched on only in the zero load region of the calendar and in the vicinity of the region. The apparatus is suitable for both heat-resistant rolls and polymer rolls. This is because no roll is displaced from the position by this apparatus, and only a slight load is caused. The wear ring 7 that is crimped to the load wheel 9 is only added to the roll. This device does not prolong roll exchange time. This is because the device remains attached to the calendar when the roll is changed. The load on the load wheel is applied, for example, by a hydraulic or pneumatic cylinder, or by other actuators that cause direct movement. The device has a leverage, and the cylinder force is transmitted to the load wheel with this leverage. In normal operation when the zero load problem has not occurred, the device is disconnected from the roll shaft by the cylinder.

  In addition to the embodiments described above, the present invention also has other embodiments. In another embodiment of the invention, the load can be applied by a sliding bearing member to be positioned on the main bearing bush. The sliding bearing member is lubricated through a lubrication region of the main bearing. One possible solution is a bearing bush which is separately rolled and supported on the axis of the roll. In all these embodiments, it is conceivable to apply a tensile load instead of a thrust load. One solution for placing the tensile load on the roll or its axis is a chain link or belt link that is stretched to a specific stress either permanently or only during the risk of zero load. The present invention can also be applied in combination with a cylinder and a support portion of another rotating mechanical mechanism. Even in the area where the mantle is vacant at the end of the roll, a load can be applied if there is sufficient space there.

It is the conceptual diagram which looked at this invention from diagonally upward. It is the conceptual diagram which looked at this invention from the side.

Explanation of symbols

1 Roll 2 Shaft 3 Bearing Bush 4 Load Arm 5 Load Fork 6 Hydraulic Cylinder 7 Wear Ring 8 Fork Body 9 Load Wheel 10 Holding Part 11 Holding Part

Claims (12)

A method of alleviating the zero load in relation to the bearing of the machine Organization for rotation of the fiber web machine,
The machine Organization is Shora a load weight in the load direction,
The different load heavy and the load direction against the machine Organization, wherein at least in a region where there is a risk of zero load at the time of processing, applied by the two load wheels in contact with the different positions in the rotation direction of the mechanical system, that And how to. The different loads is characterized in that it is multiplied by the angle of 75-105 ° with respect to the load direction to the mechanical system, the method according to claim 1. The different loads is characterized in that it is directed against the axis of the mechanical system, the method according to claim 1. The different load heavy characterized in that it is directed against the mantle of the mechanical system, the method according to claim 1 or 2. The different load heavy characterized in that it is directed against a separate bearing arranged to the axis of the mechanical system, the method described in 請 Motomeko 1-4 Neu Zureka 1 Section. Wherein the mechanical mechanism to be subjected to load a roll calendar, the method described in item 1 請 Motomeko 1-5 Neu Zureka. An apparatus for mitigating zero load area of the bearing for a machine Organization rotating to be a load in the vertical direction, the machine Organization for rotating at least one of the mantle, of the rolling bearing disposed in the shaft and a main shaft receiving the type,
To form a load different from the load direction against the machine Organization, characterized that you have at least one load Organization comprising two load wheels in contact with the different positions in the rotation direction of the mechanical system Equipment. The load Organization is characterized in that it is placed at an angle of 75-105 ° with respect to the load direction, The apparatus of claim 7. The load Organization includes arranged load-ring on the shaft, the actuator that cause linear movement, it is possible crimped to the load-ring by the actuator, and wherein the load wheel coupled with actuator 9. The device according to claim 7 or 8, characterized in that It characterized in that it has a separate bearing bush arranged on the shaft in order to transmit the load weight to the shaft, according to claim 7 or 8. The different load heavy, characterized in that it has a mechanism for directing the mantle of the machine Organization rotating apparatus according to claim 7 or 8. Characterized in that it contains a machine configuration for forming a tensile load, according to claim 7, 8, 10 or 11.

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