JP5601902B2 - Journal bearing - Google Patents

Description

  The present invention relates to a journal bearing that supports a rotating shaft of a large rotating machine such as a steam turbine or a compressor.

  Conventionally, there has been known a journal bearing having a bearing body having a bearing surface for supporting a rotating shaft on the inner peripheral side, and a bearing base disposed on the outer peripheral side of the bearing main body for supporting the bearing body ( For example, see Patent Document 1). The bearing stand is fixed to the casing of the rotating machine, and a bearing metal such as a white metal is provided on the inner peripheral surface of the bearing body in order to improve lubrication characteristics.

  Further, the outer peripheral surface of the bearing body is subjected to spherical processing, and this outer peripheral surface is engaged and supported by the spherical seat of the bearing base. The curvature of the outer peripheral surface of the bearing body and the curvature of the spherical seat of the bearing base are set to be approximately the same size. Therefore, since the bearing body can swing so as to slide around the center of the spherical surface by this spherical surface, each of the rotating shaft and the bearing body is considered in advance in consideration of the amount of alignment of the axis when assembling the rotating shaft. It can be installed so that the axes are parallel. In addition, even if the alignment of the rotating shaft changes during the rotation of the rotating shaft, the bearing body tilts to exhibit a self-aligning function so as to follow the inclination of the rotating shaft, and the bearing function is impaired. Can be prevented.

  In the journal bearing described in Patent Document 1, in order to reduce the frictional force generated in the spherical seat and improve the alignment performance, an oil groove is formed in the spherical seat and lubricating oil is supplied to the oil groove. Has been proposed. In addition, when starting the rotation of the rotating shaft, supplying high-pressure lubricating oil to the oil groove of the spherical seat reduces the contact resistance between the bearing body and the bearing base, and allows the rotating shaft to rotate smoothly. To be able to

JP-A-5-268743

  By the way, during operation of rotating machines such as steam turbines and compressors, the bearing stand may be deformed by the temperature and pressure in the casing due to operating conditions such as load and outside air temperature. May change significantly. In particular, when any one of the pair of journal bearings supporting both ends of the rotating body is deformed, or when the pair of journal bearings are deformed differently, the rotating shaft is largely inclined, whereby the rotating body A so-called one-side contact phenomenon occurs on the contact support surface between the bearing body that supports the bearing and the bearing base. Due to the one-sided phenomenon, abnormal heat generation may occur, and as a result, the bearing body and the bearing stand may be seized.

  This invention is made | formed in view of the said subject, Comprising: It aims at providing the journal bearing which can suppress the contact | abutting of the bearing main body and the bearing stand.

In order to solve the above problems, the present invention proposes the following means.
That is, the journal bearing according to the present invention includes a bearing body having a bearing surface that supports the rotating shaft on the inner peripheral side, and a bearing base provided on the outer peripheral side of the bearing main body. In a journal bearing in which a contact support surface between them has an arc shape in a cross section including the axis of the rotary shaft, lubricant supply means for supplying lubricant to the contact support surface, and a contact between the bearing body and the bearing base And a lubricating oil supply means that performs the lubricating oil supply operation when a detected value per piece by the piece contact detecting means exceeds a preset threshold value. When the detected value per piece after a lapse of a certain time from the start of the supply operation still exceeds the threshold, the supply operation is performed by supplying the lubricating oil at a higher pressure. Characterized by increasing the pressure of Namerayu stepwise.

  According to the journal bearing having such a feature, when a contact occurs on the contact support surface, lubricating oil can be supplied to the contact support surface, so that the load acting on the contact support surface is reduced. In addition, the self-aligning action by the contact support surface can be promoted.

Here, when the lubricating oil is supplied at an excessive pressure, a phenomenon that the bearing body is separated from the bearing base by the oil film of the lubricating oil (hereinafter referred to as oil film separation) occurs. When this oil film separation occurs, vibrations are generated in the rotating body and the bearing system, preventing stable rotation of the rotating body, and the reliability of the bearing is lost.
On the other hand, in the present invention, since the pressure of the lubricating oil is increased stepwise, the excessive pressure of the lubricating oil is prevented from acting on the contact support surface, thereby preventing oil film separation by the lubricating oil. be able to.

  Thus, by increasing the pressure of the lubricating oil stepwise, oil film separation by the lubricating oil can be reliably prevented. Further, as will be described later, for example, when the one-piece detection means acquires the degree of one-piece contact based on the temperature in the vicinity of the contact support surface, the self-aligning action on the contact support surface is expressed after supplying the lubricant. However, it takes a certain amount of time for the one-shot detecting means to detect the changed temperature. Therefore, after the lubricating oil supply operation is once performed, the self-aligning action can be effectively utilized by performing the lubricating oil supply operation again after a while. As a result, it is possible to smoothly suppress the one-side contact while saving the supply amount of the lubricating oil.

  In the journal bearing according to the present invention, the lubricating oil supply means performs the lubricating oil supply operation only for a predetermined time set shorter than the predetermined time.

  According to the journal bearing having such a feature, when the lubricating oil pressure is not increased stepwise, the supply is temporarily stopped after supplying the lubricating oil for a predetermined time, and then the lubricating oil is supplied. Stepwise supply operation is performed such as supplying a lubricant having a higher pressure than the previous supply operation. As a result, the self-aligning function can be made to function at an appropriate supply pressure while avoiding excessive supply of the lubricating oil, and it is possible to effectively prevent contact with one another while saving the supply amount of the lubricating oil. it can.

  Further, in the journal bearing according to the present invention, the piece contact detection means includes a pair of sensors that are spaced apart in the axial direction and measure a physical quantity in the vicinity of the contact support surface, and are detected by these sensors. A difference between physical quantities is a detected value per piece.

  When the one-side contact occurs, the bearing main body and the bearing base come into contact only on either side of the contact support surface in the axial direction of the rotating body. Therefore, by attaching sensors on both sides of the contact support surface in the axial direction, and obtaining the difference between the physical quantities detected by the sensor, the degree per piece can be obtained.

  In the journal bearing according to the present invention, the physical quantity is any one of temperature, stress, and displacement.

  When the one-side contact occurs, only one side of the contact support surface in the axial direction of the rotating body causes an increase in heat generation, an increase in contact pressure, or deformation. Therefore, by detecting any of temperature, stress, and displacement with the pair of sensors and grasping the difference between them, the degree of hitting can be appropriately acquired.

  According to the journal bearing of the present invention, when contact is generated on the contact support surface, lubricating oil is supplied to the contact support surface to reduce the load acting on the contact support surface and By promoting the self-aligning action of the contact support surface in the contact support surface, it is possible to suppress the piece contact.

It is a schematic block diagram of the rotary machine provided with the journal bearing which concerns on embodiment of this invention. It is a schematic block diagram of the journal bearing which concerns on embodiment of this invention. It is a flowchart which shows the flow of a process of the control part of the lubricating oil supply means in the journal bearing which concerns on embodiment of this invention. It is an example of the graph which shows the temperature and pressure at the time of supplying lubricating oil by a lubricating oil supply means.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS.
Drawing 1 is a schematic structure figure of rotating machine 1 provided with journal bearing 10 (10A, 10B) of an embodiment. A rotary machine 1 is a large-sized device such as the above-described turbine or compressor, and includes a rotary shaft 3 that supports a rotary unit 2 such as a moving blade in a casing 4. A pair of journal bearings 10 </ b> A and 10 </ b> B that support the rotary shaft 3 so as to be rotatable around the axis O are provided on the side and the other side.

  As shown in FIGS. 1 and 2, the journal bearing 10 includes a bearing body 20, a bearing base 30, a lubricating oil supply unit 40, and a piece contact detection unit 50.

  As shown in FIGS. 1 and 2, the bearing body 20 is disposed on the outer peripheral side of the rotating shaft 3, and a bearing metal 21 whose inner peripheral surface is slidably contactable with the outer peripheral surface of the rotating shaft 3, and the bearing The bearing housing 22 is arranged on the outer peripheral side of the metal 21 and is integrally fixed to the bearing metal 21. In the bearing body 20, the inner peripheral surface of the bearing metal 21 is a bearing surface 20a. By making the bearing surface 20a a low friction surface, the lubrication characteristics with the rotating shaft are improved. .

  Further, the outer peripheral surface 20b of the bearing body 20 itself, which is the outer peripheral surface of the bearing housing 22, is formed in an arc shape that protrudes radially outward of the axis O in a cross section including the axis O of the rotary shaft 3. That is, the circular arc is formed in a spherical shape extending over the entire area in the circumferential direction of the axis O.

  The bearing stand 30 is provided so as to extend from the inner surface of the casing 4 of the rotary machine 1 toward the inner side in the axis O direction, and supports the bearing body 20 from the outer peripheral side thereof. That is, the bearing base 30 is provided with a hole 30a penetrating in the direction of the axis O, and the inner peripheral surface of the hole 30a is in contact with the outer peripheral surface 20b of the bearing main body 20 in the circumferential direction. 20 is supported.

  The inner peripheral surface of the bearing base 30 itself, which is the inner peripheral surface of the hole 30a, is a spherical surface formed in an arc shape that protrudes radially outward of the axis O in a cross section including the axis O of the rotary shaft 3. That is, the spherical seat 30b is formed in a spherical shape in which the circular arc extends over the entire area in the circumferential direction of the axis O. The curvature of the spherical seat 30b is set to be substantially the same as the curvature of the outer peripheral surface 20b of the bearing body 20, so that the spherical seat 30b and the outer peripheral surface 20b of the bearing body 20 are in contact with each other over the entire area.

  A contact support surface 11 between the bearing body 20 and the bearing base 30 is formed by the spherical seat 30b and the outer peripheral surface 20b of the bearing body 20, and the bearing body 20 has a spherical shape of the contact support surface 11. Accordingly, it can swing so as to slide around the center of the spherical shape. Thereby, the self-aligning action by the bearing main body 20 and the bearing base 30 is expressed, and when the rotation shaft 3 is slightly inclined, the rotation shaft 3 is automatically in an appropriate state in which the inclination of the rotation shaft 3 is not one-sided. Returned to

  Further, as shown in FIG. 2, an oil groove 31 is formed in the spherical seat 30b of the bearing base 30 so as to be recessed outward in the radial direction of the one-stage axis O near the center of the spherical seat 30b. Lubricating oil is supplied to the oil groove 31 by the lubricating oil supply means 40.

  As shown in FIG. 2, the lubricating oil supply means 40 includes a lubricating oil supply path 41 that is drilled in the bearing base 30 and has one end opened to the oil groove 31, and a lubricating oil storage section 42 in which the lubricating oil is stored. A pump device 43 capable of supplying lubricating oil from the lubricating oil storage unit 42 to the lubricating oil supply passage 41, and a control unit 46.

  The pump device 43 includes a pump main body 44 configured to be able to pump the lubricating oil in the lubricating oil storage section 42 into the lubricating oil supply path 41, and a drive source 45 capable of driving the pump main body 44 with an arbitrary output. It is configured. The control unit 46 drives the drive source 45 with a predetermined output on the basis of an input from a piece contact detection unit 50 described later, thereby causing the pump device 43 to supply the lubricating oil.

  The one-piece detection means 50 includes temperature sensors 51 and 51 such as a pair of thermocouples. These temperature sensors 51, 51 are arranged in the vicinity of the contact support surface 11 so as to be separated from each other with respect to the axis O. In this embodiment, the temperature sensors 51, 51 are arranged at positions separated from each other in the direction of the axis O of the spherical seat 30 b of the bearing stand 30. It is provided so as to be buried in the spherical seat 30b. In these temperature sensors 51, 51, outputs based on the detected temperatures are respectively input to the control unit 46.

  Here, the processing flow of the control unit 46 in the lubricating oil supply means 40 will be described with reference to the flowchart shown in FIG. In the lubricating oil supply means 40, the control unit 46 performs the following processing to increase the pressure of the lubricating oil to be supplied stepwise.

That is, when the processing of the control unit 46 is started with the start of the operation of the rotary machine 1, first, the control unit 46 first determines the difference between the outputs of the pair of temperature sensors 51, 51 input to the control unit 46, that is, the temperature. It is determined whether or not the difference ΔT is equal to or greater than _a predetermined threshold value ΔT _a (step S1). Here, the threshold value ΔT _a means a temperature difference detected by the temperature sensors 51 and 51 to the extent that one-side contact occurs.

When it is determined that the temperature difference ΔT is less than the threshold value ΔT _a (step S1: No), the control unit 46 performs a process of waiting until the temperature difference ΔT is equal to or greater than _a predetermined threshold value ΔT _a .
On the other hand, if it is determined that the difference [Delta] T is equal to or larger than the threshold value [Delta] T _a, (step S1: Yes), the control unit 46 performs a process for starting the supply of the lubricating oil at a predetermined pressure to the pump device 43 ( Step S2).

Next, the control unit 46 determines whether or not _a predetermined supply continuation time ta has elapsed since the supply of the lubricating oil was started (step S3). Here, the supply duration t _a means a time for continuously supplying lubricating oil with a constant pressure.
When the predetermined time _{t a} is judged to not elapsed (step S3: No), the control unit 46 waits until a predetermined time _{t a} has passed.
On the other hand, if it is determined that the predetermined time t _a has passed (step S3: Yes), the control unit 46 performs a process of stopping the supply of lubricating oil to the pump device 43 (step S4). Specifically, the control unit 46 sends a command to stop the drive to the drive source 45 in the pump device 43.

Subsequently, the control unit 46, determines whether the supply interval time t _b from the supply is started the lubricating oil has passed (step S5). Here, the feed interval time t _b, means a distance of the stage in the case of stepwise increasing the pressure is set to be longer than the supply duration t _a.

When the supply interval time t _b is determined to not elapsed (step S5: No), the control unit 46 waits until the supply interval time t _b elapses.
On the other hand, if it is determined that the supply interval time _{t b} has elapsed (step S5: Yes), the control unit 46, the output of the difference of the pair of temperature sensors 51 and 51 are input to the control unit 46, i.e., the temperature difference It is determined whether or not ΔT is equal to or greater than _a predetermined threshold ΔTa (step S6).

When it is determined that the temperature difference ΔT is less than the predetermined threshold value ΔT _a (step S6: No), the process of the control unit 46 returns to step S1, and the temperature difference ΔT becomes equal to or greater than the threshold value ΔT _a again. Wait until.
On the other hand, when it is determined that the temperature difference ΔT is still equal to or greater than the threshold value ΔT _a (step S6: Yes), when the lubricating oil is supplied at a pressure one step higher than before the lubricating oil supply is stopped, the predetermined lubrication is performed. It is determined whether or not the maximum oil pressure _Pmax is exceeded (step S7). Here, the maximum pressure P _{max of the} lubricating oil means the pressure of the lubricating oil at which the oil film is separated by the lubricating oil supplied to the bearing body 20 and the bearing base 30.

When the control part 46 judges that it exceeds the maximum pressure _Pmax of lubricating oil (step S7: Yes), the process of the control part 46 is complete | finished. This prevents the supplied lubricating oil from exceeding the maximum pressure _Pmax .
On the other hand, if it is determined that the pressure is below the maximum lubricating oil pressure _Pmax (step S7; Yes), the controller 46 causes the pump device 43 to have a pressure one step higher than before stopping the lubricating oil supply, that is, finally. A process of starting the supply of the lubricant at a pressure one step higher than when the lubricant is supplied is performed (step S8).

After step S8, the control unit repeats the processes of steps S3 to S7 again. As a result, the pressure of the supplied lubricating oil increases stepwise unless the temperature difference ΔT is less than or equal to the threshold value ΔT _a and the pressure of the supplied lubricating oil does not exceed the maximum pressure _Pmax. .

Next, the operation of the journal bearing 10 configured as described above will be described based on a specific example with reference to FIG.
When the rotary shaft 3 is rotating normally after the operation of the rotary machine 1 is started, the bearing main body 20 and the bearing stand 30 are in contact with each other substantially uniformly in the entire area in the axis O direction on the contact support surface 11 therebetween. are therefore not a difference is generated in the temperature detected by the pair of temperature sensors 51, 51, it becomes even less than the threshold value [Delta] T _a in a case where the difference occurs.

  Here, when the temperature, pressure, or the like inside the casing 4 changes during operation of the rotating machine 1 depending on operating conditions such as a load and an outside air temperature, one of the pair of journal bearings 10A and 10B that support the rotating shaft 3 is deformed. By doing so, or the pair of journal bearings 10A and 10B are deformed differently, the rotary shaft 3 is inclined from the original axis O. In this case, in each journal bearing 10, on the contact support surface 11 between the bearing main body 20 and the bearing base 30, a so-called piece in which the bearing main body 20 and the bearing base 30 come into contact only on one side in the axis O direction. A hit phenomenon occurs.

When such a one-side contact phenomenon occurs, frictional heat is generated on the contact support surface 11 only on one side where the bearing body 20 and the bearing base 30 are in contact with each other. Thus, as shown in time _{t 0} in FIG. 4 (a), the value of the difference [Delta] T of the temperature based on the detection of a pair of temperature sensors 51, 51, equal to or larger than the threshold value [Delta] T _a. As a result, as shown at time t ₀ in FIG. 4B, the lubricating oil having the pressure P 1 is supplied to the lubricating oil supply passage 41 by the pump device 43.

When this lubricating oil passes through the lubricating oil supply passage 41 and reaches the oil groove 31, the pressure P1 is applied between the outer peripheral surface 20b of the bearing body 20 and the spherical seat 30b of the bearing base 30, that is, the contact support surface 11. Of lubricating oil is supplied. Operation of supplying the lubricating oil is conducted only over the supply duration t _a. At this time, the load acting on the one-side contact portion of the contact support surface 11 is reduced by the pressure P1 of the lubricating oil. Furthermore, the expression of the self-centering action by contacting the support surface 11 by the pressure P ₁ of the lubricating oil is facilitated.

As shown in FIG. 4 the time t ₁ of (a), exceeds after supply interval time t _b from the supply is started the lubricating oil has passed in the pressure P _1, the difference ΔT is still the threshold T _a temperature If it has, as shown in FIG. 4 (b), the supply operation of the lubricating oil is carried out at a raised pressure P ₂ than before lubricating oil supply stop. Operation of supplying lubricating oil in the pressure P ₂ is also performed by supplying duration t _a.

The pressure P ₂ of the lubricating oil, the same, the load acting on the uneven contact portion in contact supporting surface 11 is reduced, further, the expression of the self-centering action by contacting the support surface 11 is facilitated. Then, after the supply start of the operation of the lubricating oil supply of the lubricating oil is stopped when the supply duration time t _a has passed. Thereafter, as shown in the time t ₂ of FIG. 4 (a), when the difference ΔT of the temperature still exceeds the threshold value T _a, as shown in FIG. 4 (b), than previous lubricant supply stop further lubricating oil is supplied at a raised pressure P _3.

Then, by the lubricating oil of the pressure P _3, the result of automatic alignment effect was prompted with load per piece can be reduced, when the partial contact is completely eliminated, shown in the time t ₃ shown in FIG. 4 (b) as such, results in the difference [Delta] T of the temperature is below a threshold [Delta] T _a, until the difference [Delta] T of the temperature again exceeds the threshold value [Delta] T _a, there is no possibility that the lubricating oil is supplied. Thus, in the present embodiment, the one-sided contact is eliminated by increasing the pressure of the lubricating oil stepwise.

  As described above, according to the journal bearing 10 of the present embodiment, when the one-side contact occurs on the contact support surface 11, the lubricant supply operation of the lubricant supply unit 40 based on the detection of the one-piece detection unit 50 is performed. Since the lubricating oil can be supplied to the contact support surface 11, the load acting on the contact support surface 11 can be reduced, and the self-aligning action by the contact support surface can be promoted.

Here, when the lubricating oil is supplied at an excessive pressure exceeding the maximum pressure P _max and the bearing main body 20 and the bearing base 30 are separated from each other by the lubricating oil, vibrations are generated in the rotating portion 2 and the journal bearing 10. As a result, the stable rotation of the rotating part 2 is hindered, and the reliability of the journal bearing 10 is lost.

In contrast, in the present embodiment, the pressure of the lubricating oil is increased stepwise, and when it is determined that the pressure of the lubricating oil to be supplied exceeds _Pmax , the lubricating oil is supplied. Therefore, it is possible to prevent the oil film from being separated by the lubricating oil by avoiding the excessive pressure of the lubricating oil from acting.

Further, the lubricating oil supply means 40 performs the lubricating oil supply operation when the temperature difference ΔT by the one-piece detection means 50 exceeds the threshold value ΔT _a , and the supply interval time t _{b has} elapsed from the start of the supply operation. If the later temperature difference ΔT still exceeds the threshold value ΔT _a , the lubricating oil is supplied at a higher pressure.
Here, even if the self-alignment effect on the contact support surface 11 appears after the supply of the lubricating oil and the one-side contact starts to be eliminated, a certain amount of time is required until the one-side detection means 50 detects the temperature changed thereby. It takes time. Therefore, after the lubricating oil supply operation is performed once as described above, the self-aligning action can be effectively utilized by performing the lubricating oil supply operation with a larger pressure after a while. . Thereby, without causing oil film separation, it is possible to smoothly suppress the one-sided contact while saving the supply amount of the lubricating oil.

Further, in the present embodiment, the lubricating oil rather than simply increased stepwise pressure, temporarily stopped the supply after supplying only the lubricating oil supply duration t _a, followed by in supplying lubricating oil Stepwise supply operation is performed such as supplying a lubricant having a higher pressure than the previous supply operation. As a result, the self-aligning function can be made to function at an appropriate supply pressure while avoiding excessive supply of the lubricating oil, and it is possible to effectively prevent one-sided contact while saving the supply amount of the lubricating oil. .

  Further, when the one-side contact occurs, by utilizing the principle that the bearing main body 20 and the bearing base 30 come into contact with each other only in one of the axial directions O of the contact support surface 11 to generate frictional heat, The degree of contact can be easily obtained from the difference between the detection values of the temperature sensors 51 and 51 attached to both sides of the contact support surface 11 in the axis O direction.

As mentioned above, although embodiment of this invention was described in detail, unless it deviates from the technical idea of this invention, it is not limited to these, A some design change etc. are possible.
For example, in the present embodiment, the pair of temperature sensors 51, 51 are used as the one-piece detecting means 50, but instead of this, a stress detection sensor such as a pair of strain gauges may be used. That is, when the one-side contact occurs, a difference occurs in the stress generated in the bearing stand 30 on both sides of the contact support surface 11. By acquiring this difference as the degree of hitting, the hitting can be properly grasped.

  Furthermore, a pair of displacement sensors may be used as the one-piece detection means 50. When the one-side contact occurs, a difference occurs in the amount of displacement of the bearing stand 30 on both sides of the contact support surface 11. By acquiring this difference as the degree of hitting, the hitting can be properly grasped.

Further, when stopping the supply of the lubricating oil from the start of the supply of lubricating oil when the supply duration time t _a elapsed to detect the degree of per piece rotary shaft 3, if in the direction in which the contact the piece is eliminated " An “in-alignment” signal may be generated, and if there is no change in the degree of contact, a “no change” signal may be generated, and further, an “alarm” signal may be generated if the contact is in the direction of increasing. As a result, it is possible to grasp whether or not the supply of the lubricating oil is appropriate, and it is possible to eliminate the one-sided contact more smoothly and safely.

The lubricating oil supply means 40 in the embodiment, once stops supply after supplying only the lubricating oil supply duration t _a, then, after a while open between, i.e., the supply from the start of the supply of the lubricating oil Although the lubricating oil having a pressure higher by one step is supplied after the interval time t _b elapses, the present invention is not limited to this, and there is no need to provide an interval between the operations of supplying the lubricating oil. The structure which supplies lubricating oil may be sufficient. Also by this, the piece contact can be smoothly suppressed.

  Further, in the present embodiment, the outer peripheral surface 20b of the bearing body 20 and the spherical seat 30b of the bearing base 30, that is, the contact support surface 11 are spherical, but may be aspherical, for example, an axis line. The shape of the contact support surface 11 in the cross section including O may be an arc shape that is convex outward in the radial direction of the axis O. Thereby, the self-aligning action by the contact support surface 11 can be expressed.

Furthermore, the lubricating oil supply means 40 and the piece contact detection means 50 may be provided not only in the structure provided in the bearing stand 30 but also in the bearing body 20.
The present invention can also be applied to, for example, a journal bearing having a tilting pad, that is, it can be applied regardless of the type of bearing. Thereby, the one piece contact in various journal bearings can be eliminated.

DESCRIPTION OF SYMBOLS 1 Rotating machine 2 Rotating part 3 Rotating shaft 4 Casing 10 Journal bearing 10A Journal bearing 10B Journal bearing 11 Contact support surface 20 Bearing body 20a Bearing surface 20b Outer peripheral surface 21 Bearing metal 22 Bearing housing 30 Bearing base 30a Hole 30b Spherical seat 31 Oil Groove 40 Lubricating oil supply means 41 Lubricating oil supply path 42 Lubricating oil storage part 43 Pump device 44 Pump body 45 Drive source 46 Control part 50 Per-piece detection means 51 Temperature sensor

Claims (4)

A bearing main body having a bearing surface for supporting the rotating shaft on the inner peripheral side, and a bearing base for supporting the bearing main body, and a contact support surface between the bearing main body and the bearing base includes an axis of the rotating shaft. In journal bearings that have an arc shape in cross section,
Lubricating oil supply means for supplying lubricating oil to the contact support surface;
A contact detection means for detecting the contact between the bearing body and the bearing base;
The lubricating oil supply means includes
When the detection value per piece by the one-piece detection means exceeds a preset threshold value, the lubricating oil is supplied.
When the detected value per piece after a lapse of a certain time from the start of the supply operation still exceeds the threshold value, the supply operation is performed by supplying the lubricating oil at a higher pressure. Journal bearing characterized by gradually increasing the pressure of the lubricating oil . The lubricating oil supply means includes
Journal bearing according to claim 1, characterized in that the supply operation of the lubricating oil, only for a predetermined time determined shorter than the predetermined time. The one-piece detection means includes
A pair of sensors that are arranged apart in the axial direction and measure a physical quantity in the vicinity of the contact support surface;
The journal bearing according to claim 1 or 2 , wherein a difference between physical quantities detected by the sensors is a detected value per piece. The journal bearing according to claim 3 , wherein the physical quantity is any one of temperature, stress, and displacement.

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