JPS602532B2 - Bearing protection detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a detection device for detecting the bearing of a rotating body rotating around a single axis.

When the rotating body is a driven member of the magnetic coupling of a magnet drive pump, the rotating body is placed in the moving liquid of the pump, and a partition is provided between it and the drive side magnet to prevent pump operation. The power for this is transmitted through this partition by magnetic attraction and repulsion.

If the bearing that supports such a rotating body gets confused, the rotating body will be displaced, and if the trouble progresses, the rotating body will come into contact with the partition wall,
This may be destroyed, leading to accidents such as leakage of the transferred liquid. Magnetic drive pumps are often used to transfer strong acids and alkaline liquids, and spillage of the transferred liquid can result in serious accidents. Therefore, there has been a need for a blind detection device that can accurately determine the progress of the bearing of such a rotating body.

Conventionally, as a means of detecting abnormalities in bearings caused by bearing protection, etc., the temperature near the whip bearing sliding and its temperature rise rate have been measured, as described in Tokubatsu No. 148647/1983. A method of detecting an abnormal state of this sliding surface and a device that detects an abnormality of a bearing by monitoring the formation state of a bearing oil film, as described in Japanese Patent Publication No. 53-95663, are known. It is being

However, with these conventional technologies, it is not possible to directly detect the flow rate of the bearing, and only indirectly detect an abnormality in the bearing.Furthermore, in addition to this, Detecting abnormalities in submerged bearings is difficult for the following reasons.

In other words, since the sliding surface of the submerged bearing of a magnetic drive pump is in the liquid being pumped, the temperature near this sliding surface is affected by the temperature of the liquid being transferred, specific heat t, thermal conductivity, etc. In the method described in Shokyu-148M7, it is difficult to set reference values for comparing the temperature near the sliding surface and the temperature rising flow to match the characteristics of the transferred liquid.
Particularly in the case of a pump that transfers many types of liquids, it is extremely difficult to set the above reference value.

In the case of pumps for transferring chemical liquids, the rattan and bearings that come into contact with the liquid to be transferred need to be resistant to corrosion, and for this reason, ceramics and corrosion-resistant synthetic resins are often used as materials.

However, in the device described in Tokusekki No. 53-95663,
In order to electrically detect oil film rupture, the oil film must be an electrical insulator and the shaft and bearings must be electrical conductors. Therefore, if the shaft or bearing is made of ceramic or synthetic resin, or if the chemical liquid to be transferred is an electrical insulator, this known hawk cannot be used. An object of the present invention is to solve the problems associated with the above-mentioned known techniques, and to eliminate the need for indirect means such as detecting the temperature and temperature rise rate of the sliding surface of the bearing or detecting the state of oil film formation. Another object of the present invention is to provide a detection device for detecting whether the bearing is covered or not, which can directly and reliably detect the amount covered by the bearing without considering the electrical conductivity of the bearing or the transferred liquid. The device of the present invention is provided with one or two pairs of sensors diametrically opposed to the center of rotation of the rotating body on either one of a rotating body and a stationary body placed close to the rotating body, and these sensors on the other side. and a corresponding sensed object, and calculate the time required from when the sensed object is sensed by one sensor of each pair until it is sensed by the other sensor of the corresponding pair when the rotating body rotates, and the other sensor of each pair. The structure is configured to detect the difference between the time required to be detected by one sensor and the time required to be detected by one sensor of the pair, and to detect the degree of protection of the bearing based on the detected value. can be easily and accurately detected.

EMBODIMENT OF THE INVENTION Hereinafter, embodiments in which the present invention is applied to a pump will be described with reference to the drawings. In FIG. 1, 1 is a partially shown pump, 2 is an inverter of the pump 1, 3 is a support shaft that supports the inverter 2 at one end, and 4 can be rotated integrally with the support 3 by a key 5. The cylindrical rotating members 6 and 7 fixed in this manner are bearings that rotatably support the support shaft 3.

The bearing 6 on the - side is the vertical frame 9 of the base 8 that supports the pump 1.
The other bearing 7 is held in a support frame 10 fixed to a vertical frame by welding or the like. In addition, the support frame also functions as a partition wall to prevent the liquid transferred by the pump from flowing out to the outside. Reference numeral 11 denotes a drive motor fixedly attached to the base 8, and its motor ball 12 extends horizontally so as to have the same rotation center as the support shaft 3.

A line connecting the rotation centers of the motor shaft 12 and the support shaft 3 is indicated by x-Y in FIG. A joint member 13 having a fork-shaped cross section and a generally cylindrical shape as shown in the drawing is attached to the extending end of the motor shaft 12 by a key 14 so as to be able to rotate integrally with the motor shaft. The fork-shaped end portion of the joint member 13 is bent inward, and a driving example magnet 15 constituting a magnetic coupling is attached to the bent end portion, that is, the inner peripheral portion. A sub-side magnet 16 facing the drive-side magnet 15 is embedded within the rotating member 4. The structure of this magnetic coupling itself is conventional.

. The rotating member 4 and the support frame 10 are both magnets 15 and 16.
It is made of a material that does not affect the surrounding area, such as synthetic resin or stainless steel. When the motor 11 is energized, the joint member 13 rotates in one direction via the motor shaft 12.

With this rotation, the rotating part 4 is driven to rotate in the same direction together with the support shaft 3 due to the attraction and repulsion of both magnets 15 and 16, thereby rotationally driving the inflator 2 and driving the pump. In this embodiment, the rotating member 4 and the support shaft 3 correspond to the rotating body of the present invention, and the vertical frame 9 of the base 8 corresponds to the stationary body.

A pair of bearings 6 and 7 correspond to the bearings to be detected. One side surface 4a of the rotating part village 4 along the radial direction is close to the wall surface of the vertical frame 9 in a parallel state with a slight gap therebetween.

A pair of sensors 17 and 18 are provided on one of the opposing proximal surfaces, that is, in this embodiment, on the vertical frame 9 on the stationary body side,
A single mark 19 as a sensed object is provided in the rotating part village 4 on the other rotating body side. The pair of sensors 17 and 18 are arranged on the same radius with respect to the rotation centers X and Y, and diametrically opposed to each other. other mark 1
Reference numeral 9 is disposed on the same radius as the sensor with respect to the center of rotation X-Y, and corresponds to be sensed by this sensor when the sensor 9 is placed at the same rotational position as the sensors 17 and 18. Materials and marks 19 for these sensors 17 and 18
Although various materials can be considered, the following combinations can be used.

Note that these materials and combinations themselves are commonly used in sensor technology.

When the bearings 6 and 7 are maintained, the rotation centers of the support shaft 3 and the rotating member 4 are moved from the normal rotation center X-Y before maintenance.
It will be deflected by the amount that you received.

By detecting this amount of deviation using a pair of sensors 17 and 18 and a mark 19, the degree of protection of the bearings 6 and 7 is detected. The above detection principle of the present invention will be explained with reference to FIGS. 2 and 3.

In FIG. 2, a pair of sensors are A and B, the normal rotation center is P, the rotation center of the rotating body after deviation is Q, and the radius of the sensors A, B and mark M is R.

The circle drawn by mark M when the rotating body is rotating around the normal rotation center P is shown as a solid line, and the circle drawn by mark M when it is rotating around a deflected center Q is shown as a broken line. show. If the amount of displacement is 6, the rotation center Q is the apex, and the angle at which the angle 2AQB connecting sensors A and B increases or decreases from 180 degrees due to displacement 〇 is 28, then 6niR is n
8... (1) Assuming that a rotating body having a mark M rotates at a constant speed in a counterclockwise direction indicated by an arrow on a circle indicated by a broken line around a deflected center of rotation Q, the mark M is detected by a sensor A. Assuming that ta is the elapsed time from sensor B until it is sensed by sensor B, tb is the elapsed time from sensor B to sensor A, and t is the time required for one revolution of the rotating body, t = ta + tb ・
...(2) Here, the time required to rotate the body by 31 degrees is short, so tta = generosity (180120) tb = intention (18M8) Therefore, ta - tb = vessel.

・t. ．． ．． h=36 melon ta-ratio) [degrees]…(3) 4t・
-・8=9.

-Three poisons of heat [degrees]--(4) From (1) and (4), 6=R
is n(90-t signra reed)---(5) i.e. ta,
8 can be found by measuring tb.

If 8 is small, it can be considered that tan8=ka (k=constant), so 6=Kamaguro...(6) Furthermore, if the variation in the rotational speed of the rotating body is negligibly small, ta + tb will be constant, so a =K(ta-tb
) (K: constant) That is, by detecting ta-tb, the amount of deviation 6 of the rotating body can be obtained, and this amount of deviation corresponds to the size of the bearing.

Various methods can be considered to obtain ta-tb.

For example, ta and tb can be detected as reference pulse count values by a counter, and arithmetic processing can be performed by an adder or a microcomputer to obtain the value of the ratio. For this purpose, the sensors A and B may be configured to be connected to an adder circuit or a microcomputer. Another method is to connect sensors A and B to an addition/subtraction counter circuit, add the reference pulse while determining ta, and subtract while determining tb, thereby directly determining the value of ta-tb. You can also do that. In any case, sensors A and B
A known electric circuit itself can be used, and electric means different from the above-mentioned calculation can also be used.
As shown in FIG. 2, if a pair of sensors A and B are provided along the horizontal direction, the vertical clearance of the bearing can be detected.

Bearing protection is also related to gravity, and in the vertical direction, that is,
Since the underside of the bearing is heavily protected, by arranging the pair of sensors in this manner, a somewhat satisfactory detection can be achieved.
Furthermore, if you want to always detect the maximum amount of protection in any direction, including the lateral protection of the bearing, an additional set of sensors C and D should be arranged as shown in Figure 3. Bye.

Sensors C and D are the normal center of rotation P' and sensor A
, B, and on a vertical line perpendicular to the horizontal line connecting sensors A and B. Both sensors C and D face each other in a right angle direction. As in FIG. 2, the circle drawn when the rotating body is on the normal rotation center P is shown by a solid line, and the circle drawn when it is on the deviated rotation center Q is shown by a broken line. The amount of deviation, that is, the maximum amount of protection of the bearing in any direction is assumed to be 6. Assuming that the vertical deviation is a, and the horizontal deviation is 62, these 6., 62 are determined by each pair of sensors A, B, C, D and mark M, as explained in FIG. Each is obtained individually by detection and calculation of the detected value by an electric circuit connected to the sensor. On the other hand, since 6 = zo 6 壬 + 6 seasons, 6 can be obtained by an appropriate arithmetic circuit using 6, , 62 as the detection output. This arithmetic circuit itself can also be constructed from a known simple electric mass circuit. This creates two pairs of sensors A, B and C.
, D so that their detection directions are orthogonal to each other, the maximum amount of misalignment in any direction can be found.

In addition, in FIGS. 2 and 3, the amount of deviation 6 and the size of the sensor are exaggerated for the sake of explanation, and in reality, the amount of deviation 6 is a microscopic 4 mm, and the sensor and the mark correspond to each other. The detection area can be sufficiently covered even when the deviation is large. If the rotational speed of the rotating body changes during detection, 1 is the above-mentioned t.
Since the value of the a10 ratio is not constant, the time required for one revolution of the mark M is measured, and 6 is determined by the above-mentioned equation (6).

Further, by determining the value of ta+tb at the same time as detecting the value of ta-tb, there is an advantage that overload or abnormally light load of a driven part, such as a pump, can be detected.

In addition, in the embodiment, the sensor was provided on the vertical frame 9 as a stationary body, and the mark 19 was provided on the rotating member 4 as a rotating body. It can also be provided on the body side. However, in the latter case, since the sensor is located on a rotating body, some ingenuity may be required for wiring to the external electric circuit. As stated above,
The present invention provides a rotating body and a stationary body placed close to the rotating body with one or two pairs of sensors diametrically opposed to the center of rotation of the rotating body, and the other is equipped with these sensors. Corresponding sensed objects are provided, and when the rotating body rotates, the time required for the sensed object to be sensed by one sensor of each pair and then sensed by the other sensor of the corresponding pair, and the time required for the sensed object to be detected by the other sensor of the corresponding pair, It is configured to detect the difference in time required from when the other sensor detects the sensor to when the sensor detects the sensor of the corresponding pair, and detects the degree of protection of the bearing based on the detected value. This has the advantage that the bearing capacity can be directly and accurately detected without relying on indirect means such as detecting the temperature of the bearing or detecting the state of oil film formation on the bearing.

[Brief explanation of drawings]

- FIG. 1 is a longitudinal sectional view of an embodiment embodying the present invention, and FIGS. 2 and 3 are explanatory diagrams showing the detection principle of the present invention. 1... Pump, 3... Support shaft, 4... Rotating member, 6
,7... Bearing, 17,18... Sensor, 19...
·mark. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. A rotating body that rotates around one axis, a bearing that rotatably supports the rotating body, a stationary body that is provided close to the rotating body, and a combination of the rotating body and the stationary body. first and second sensors provided on either one of the rotating bodies, located at positions spaced apart in the radial direction from the rotation center of the rotating body, and facing each other in the diametrical direction across the rotation center; a single sensed object provided on the other side, located at a position radially spaced apart from the center of rotation so as to correspond to the first and second sensors, and sensed by the sensor; The time required for the sensed object to be sensed by the first sensor and the second sensor during rotation, and the time required for the sensed object to be sensed by the first sensor after being sensed by the second sensor. Detect the difference between
A bearing protection detection device that detects the degree of bearing protection based on the detected value. 2 A rotating body that rotates around a single axis, a bearing that rotatably supports the rotating body, a stationary body that is provided in close proximity to the rotating body, and a bearing that is installed on either the rotating body or the stationary body. , first and second sensors located radially apart from the rotation center of the rotating body and facing each other in the diametrical direction across the rotation center, and provided on the other of the rotating body and the stationary body, and the a single sensed object that is located at a position radially spaced apart from the center of rotation so as to correspond to the first and second sensors, and is sensed by the sensor; Detects the difference between the time required from being sensed by the first sensor to being sensed by the second sensor and the time required from being sensed by the second sensor to being sensed by the first sensor. , third and fourth sensors facing each other in the diametrical direction across the center of rotation in a direction orthogonal to a diametrical line connecting the first and second sensors are arranged so as to correspond to the sensed object. and the time required for the sensed object to be sensed by the fourth sensor after being sensed by the third sensor when the rotating body rotates, and the time required for the sensed object to be sensed by the third sensor after being sensed by the fourth sensor. 1. A bearing protection detection device, comprising: a detection means for detecting a difference in time required for a bearing to be completely protected, and for detecting a maximum degree of protection of the bearing from the difference between the two required times.