RU2582758C1 - Passive element for bearing lubrication with crankcase oil in machines and mechanisms - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: passive element for lubrication of rolling bearings with crankcase oil in mechanisms consists of a collector, which is intended for collection of lubricating fluid from surface of case or with sprinkling rotating moving parts and parts of mechanism is located above lock-on point lubrication bearing capable to lubricant guide structure that allows lubricant flow by gravity and inclination angle of collector to bearing. Guide structure delivers lubricant only in point of lubrication capture bearing, which may be located: for vertical bearing in volume limited by outer diameter of inner bearing race, surface circumscribed by horizontal lines of rotation centres of balls, rollers, surface circumscribed by arc ball for rolls segment from centre of rotation to point of contact with inner cage of bearing distances from he edge of ball, roller bearing, from minimum possible to half diameter of drops of lubricant formed data oil; for horizontal or inclined oriented bearing using flowing drops in upper volume limited by surface plane passing through centres of balls, rollers, surface of outer diameter of inner bearing race, surface circumscribed by lines of rotation centres of balls, rollers, surface circumscribed by arc ball for rolls segment from centre of rotation to point of contact with inner cage of bearing distances from edge of ball, roller bearing, from minimum possible to half diameter of drops of lubricant formed by said oil; for jet available lock-on point of upper and lower volume of bearing.

EFFECT: elimination of oil deficiency in operation of bearing, reduced operating temperature of bearing due to direct oil flow through volume of rolling balls, rollers in any angular rotation speed, and longer service life.

1 cl, 3 dwg

Description

The technical field to which the invention relates is machines and mechanisms that have a crankcase with grease, rotating, moving parts capable of spraying grease, and ball or roller bearings are used in them.

Analogs are known. RU 2330211 C1 (FSUE VNIKTI IPS of Russia), July 27, 2008, where the method of spraying grease, collecting and feeding bearings in a gearbox is used. Known inventions using an oil pump, RU 2382256 C1 (Kamaz OJSC), 08/27/2008. Known methods without the use of passive elements do not allow stable lubrication of the bearings of the mechanism at all angular speeds. They have the disadvantage that the lubricant is supplied over the entire surface of the rotating parts of the bearing and at angular speeds above the critical one the lubricant ceases to enter the bearing.

The new method differs from the previous ones in that the oil is sprayed or from the pump by the correct location of the guide element with respect to the bearing. Each bearing has points of gripping, tightening the lubricant into the rolling area of the balls or rollers. And if at the same time apply lubricant to all access points to the bearing, and not to the capture point, then the oil ejection points block the flow of lubricant into the rolling area. We will deal with the location of these points.

The gripping points of the bearing, vertically located, are limited to: the outer diameter of the inner race of the bearing on one side, the surface described by the horizontal lines of rotation of the centers of the balls, the rollers on the other hand, the surface described by the arc of the ball for the rollers, from the center of rotation to points of contact with the inner race of the bearing on the third side, distances from the edge of the ball, bearing roller, from the smallest possible to the size of half the diameter of the droplets of grease that are uyutsya this oil.

I will explain in detail and clearly what constitutes the location of the capture points. Grease pick-up points are located in the bearing volume, which can be located horizontally, vertically or at an angle. Consider the vertical bearing arrangement. In the formula to indicate the first boundary of this volume, the words are used: the outer diameter of the inner race, which denote the geometric curved surface formed by the inner race of the bearing around the circumference, is indicated by the number 11 in FIG. 1, section CC, this is a curve passing through points a-e-f. Using view D in FIG. 1, the same volume boundary is indicated, which is formed by moving the a-e-f curve along the outer diameter of the inner ring through the points a-m-n-k-a. At radii greater than the circle passing through the points c-l-o-g-c in FIG. 1, view D, discharge points are located. The area of the capture points is symmetrical on both sides with respect to the vertical axis of the balls. The following geometric boundary is indicated by the words: the surface described by the horizontal lines of rotation of the centers of the balls and rollers is indicated by the number 12 in FIG. 1, section CC, this is a line passing through the points c-d, during rotation of which along the radius of the circle the next boundary surface is formed, passing through the points c-l-o-g-c in FIG. 1, view D. The following boundary is indicated by the words: the surface described by the arc of the ball for the rollers by a segment from the center of rotation to the point of contact with the inner race of the bearing is indicated by 13 in FIG. 1, section CC, this is a curve passing through points a-b-c, the rotation of which along the radius of the circle forms the following boundary surface. So, the internal geometric boundaries of the volume are indicated. Now it remains to identify the external boundaries of the volume of the gripping points, which are indicated by the words: are in a volume limited by the distances from the edge of the ball, roller, bearing, from the smallest possible to the size of half the diameter of the droplets of grease that can be formed by this oil. This curve is indicated by a dashed line and the number 14 in FIG. 1, view CC, this is a curve connecting the d-e points, during rotation of which an outer boundary surface is formed along the radius of the circle. The above description means that the guide structure with its tip should be at the minimum possible distance from the surfaces of the ball, roller or a little more, but at most no more than at a distance of half the diameter of the droplet. These dimensions ensure reliable adhesion of the lubricating fluid to the bearing parts due to surface tension forces. If the droplets flow down along the guide, then they will certainly be captured and tightened by balls, and even more so if the stream flows. The entire ball will be captured by the balls of the bearing at any angular velocity. The direction of movement of the lubricant is possible only in one vector, which is always directed from the center of the bearing to the periphery during rotation. The greater the angular velocity, the greater the value of the pulling force acting on the lubricant. When the bearing rotates, a different direction of motion of the lubricant is simply impossible at angular speeds more critical.

Most bearings have ball holding devices - these are separators, and so, their geometric volume should be excluded from the grip area, they rotate strictly around the circumference and prevent the lubricant from being drawn in.

The gripping points in a horizontally or inclined bearing, when dripping drops are used, are in the upper volume bounded by the surface of the plane passing through the centers of the balls, rollers on the one hand, the outer diameter of the inner race on the other hand, the surface described by the vertical lines of rotation of the centers of the balls, rollers on the third side, the surface described by the arc of the ball, for the roller segment, from the center of rotation to the point of contact with the inner race of the bearing on the fourth side, standing from the edge of the ball, bearing roller, from the smallest possible to the size of half the diameter of the droplets of grease that are formed by this oil; gripping points for the upper and lower bearing volume are available.

If you mentally divide the bearing in a horizontal plane into two halves: the upper and lower, then for lubrication, when using dripping drops, it is worth considering only the upper one, with a horizontal arrangement. In the rest, the area of the gripping points converges with a vertically located bearing.

For an angularly oriented bearing, it is easy to understand by analogy with the above description, in which the capture points will only be in the upper half for the dripping drops. If it is possible to create and direct a jet capable of reaching a gripping point from below, then the lower areas for horizontally and angularly oriented bearings become available.

Operating experience of machines and mechanisms leads to the conclusion that the destruction and failure of parts of mechanisms, primarily, arise as a result of rapid wear of bearings. In most cases, there are bearings in the mechanisms that fall into the area of “oil starvation”. As a result, premature wear leads to increased vibration and, as a result, to rapid wear of other parts. The operating mode of the bearing “oil starvation” is a mode in which a very small amount of lubricant enters the bearing or does not enter at all for a long time, and which may not be enough to remove heat and directly lubricate the rubbing surfaces. This unfavorable mode of the bearing occurs in cases when the lubricant is not supplied at all or is supplied simultaneously to all points of contact with the rotating parts of the bearing, at rotation speeds more critical. This is approximately 20-500 rpm. Critical angular velocities depend on the diameter of the bearing and on the properties of the lubricating fluid. With an increase in the rotation speed that is more critical, the centrifugal forces of the rotating parts do not allow oil droplets to fall into the area of moving balls, rollers, since the grease capture point becomes inaccessible. Nearby lubrication is simply discarded by rotating parts, creating a wall of rotating elements that do not let the lubricant in. Known registered inventions create operating conditions with the regime of "oil starvation", which leads to an early wear of rapidly rotating parts. Balls, rollers by centrifugal force in the first seconds of rotation throw out most of the lubricant, a high rotation speed does not allow fresh to penetrate into the rolling area of balls, rollers, and the rest of the liquid quickly heats up from hot balls and evaporates. Even if there are conditions for the formation of strong jets of lubricant that could fall into the bearing area, then these droplets flying in its direction bounce off the bearing, not reaching the rolling area, under the influence of centrifugal forces, if they are not directed only to the bearing grip point. Oil cannot just get into the grease's pick up points. It must be delivered there. Otherwise, the bearing remains without cooling and lubrication for a long time, although the bearings seem to be lubricated during disassembly and inspection.

The proposed new lubrication method delivers it precisely to the pickup point. In this case, the centrifugal effect causes the lubricant to penetrate into the rolling area of the balls and rollers.

The passive element serves to perform three functions: collection, delivery, supply of lubricant to the capture point. Conditionally consists of two parts:

- collector, the structural part of the element for collecting oil from the surfaces of the crankcase or collecting sprayed oil from rotating parts and parts of the mechanism. Such a part of the element can serve: crankcase tides, staples, plates, springs, tubes, spokes, bolts, screws, nuts, pumps, etc., any mechanical parts that are able to collect and return the collected oil to the guide structure;

- the guide, the structural part of the passive element for oil drain from the collector along the guide to the bearing gripping point. This part of the element can be made of a tube, wire, plate, in the form of an opening in the crankcase, etc., any mechanical objects that are located at an angle to the horizon and along which the lubricant can move in the right direction to the point of grease capture by the bearing.

An important distinguishing feature of the use of a passive element for lubricating bearings in machines and mechanisms is the supply of grease with a guide structure to the oil pickup point. It is desirable that the direction of rotation, at the oil supply point, strive to coincide with the direction of flow along the guide, then a laminar flow of lubricant is formed, although in case of a mismatch it can satisfy the needs of the lubricant. It all depends on operating conditions, load and angular velocity of the bearing. A passive element for bearing lubrication is a combination of a collector, a guide, and a bearing grip point.

In FIG. 2 and 3 are two fragments of the gearbox, where a passive element is used. In FIG. 2 shows a section “A-A” of the crankcase with a bearing, the upper shaft with gear, a fragment of the lower gear and the passive element itself: 1 - collector, 2 - guide (made as a whole from copper wire), 3 - fixing screws, 4 - washer , 5 - bracket. Other designations: 6 - crankcase wall, 7 - bearing, 8 - upper shaft with gear, 9 - lower gear. This drawing demonstrates that the plane of rotation of the gears intersects with the location of the collector, which allows it to collect a significant amount of lubricant sprayed by the gear.

In FIG. 3 shows a section "BB" of the crankcase with a bearing, the upper shaft with the gear, a fragment of the lower gear and the passive element itself: 1 - collector, 2 - guide, 3 - mounting screws, 4 - washer, 5 - bracket. This type of drawing demonstrates that the guide structure delivers lubricant to the grease grip area of the bearing. Here the simplest design of the passive element is applied, the wire (copper), which is a passive element, performs three functions: it is the collection, transmission and direction to the capture point.

FIG. 2 and 3 will help to understand the operation of the device. The oil reservoir 1 is located in the zone of abundant ingress of sprayed drops of oil in the working state of the device. From areas of the crankcase located above the collector, it also flows down the walls of the crankcase towards the collector. Due to a certain angle of inclination (> 5 ° from the horizontal) of the collector, the wire allows oil to drain to the next part of the element - guide 2, along which the oil enters the grease capture point, where the tip of the guide structure is located. Due to the forces of attraction and surface tension forces, the angle of inclination, the lubricant is drawn into the rolling region by centrifugal force, the balls, having received the oil, carry it across the entire rolling surface. The process is continuous, while the mechanism in which the lubricant is sprayed operates at all angular speeds.

The implementation of the invention is assumed in existing mechanisms that have bearings experiencing the regime of "oil starvation", as well as in the designed, where it is assumed the possibility of these undesirable modes. For this, several details of the passive element should be developed and implemented. It is important to remember the need for the correct relative positioning from top to bottom in the sequence: collector, guide, lubrication point, bearing. And the slope of the parts for a confident drain under the action of gravity. It is necessary to take into account the required amount of lubricant to maintain the appropriate temperature, which determines the size of the collector, the angle of inclination and its place.

For example, it is known that a bearing suffers from a gearbox that is not lubricated enough or not lubricated at all. For a stable temperature regime, he needs 2 grams of crankcase oil per second. There is a gear in the gearbox housing, which sprays radially 25 g * cm ² / s of lubricant on the crankcase walls, which is more than enough. To determine the angle of inclination, it is worthwhile to conduct a little experiment: drop the crankcase oil onto the supposed “collector guide” and determine the angle at which the lubricant, due to its properties, will steadily drain to the tip. Suppose you got a tilt angle of 25 degrees. Now you need to determine the installation location of the product. In FIG. Figure 2 shows what needs to be placed in the plane of the gear, where there is abundant spraying, and also above the bearing. Based on the observance of the above conditions, we find the desired mounting points of the collector in the crankcase. We measure the length of the guide from the lubrication point to the mount, this will be the length of the guide. We make a passive element from copper wire, make the necessary holes in the crankcase and assemble the passive element. Why made of copper wire? Because it bends easily and at the same time holds its shape well during operation. During assembly, the passive element may interfere, interfere, and it must be bent to the side. After assembly, it is easy to restore and adjust the tip of the guide so that it is strictly at the lubrication point. After obtaining the desired lubrication effect, the passive element for mass production can be made of any other material. In FIG. 2 and 3 it is seen that one end of the wire is made in the form of a ring, which allows you to securely fasten the passive element and prevent accidental rotation in the mount during adjustment. Behind the bracket, the wire is bent so that the tip of the guide hits the grease pick-up point. During the operation of the mechanism, the lubricant will be sprayed onto the crankcase walls, drain to the collector, along the collector to the guide and then to the bearing from the tip of the guide to the pickup point.

Claims (1)

A passive element for lubricating rolling bearings with crankcase oil in mechanisms, consisting of a collector, which is designed to collect lubricating fluid from the crankcase surfaces or from spray rotating, moving parts and parts of the mechanism, is located above the grease capture point by a bearing capable of releasing lubricating fluid of the guide structure, which allows the lubricating fluid to drain under the action of gravity and the angle of inclination from the collector to the bearing, characterized in that
the guide structure delivers lubricant only to the grease's gripping point with a bearing, which can be located:
for a vertically oriented bearing in a volume limited by the outer diameter of the inner race of the bearing, the surface described by the horizontal lines of rotation of the centers of the balls, rollers, the surface described by the arc of the ball, for the rollers by a segment from the center of rotation to the point of contact with the inner race of the bearing, distances from the edge of the ball , a roller of the bearing, from the smallest possible to the size of half the diameter of the droplets of grease that are formed by this oil;
for a horizontally or angularly oriented bearing, when dripping drops are used, in the upper volume bounded by the surface of the plane passing through the centers of the balls, rollers, the surface of the outer diameter of the inner race of the bearing, the surface described by the lines of rotation of the centers of the balls, rollers, the surface described by the arc of the ball, for rollers with a segment, from the center of rotation to the point of contact with the inner race of the bearing, distances from the edge of the ball, bearing roller, from the smallest possible to half the diameter ra lubricant drops that are formed by this oil; gripping points for the upper and lower bearing volume are available.

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