JP2016130566A - Bearing mechanism and pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit wear of a slide member from being caused by foreign objects taken into a gap between a rotary shaft and a bearing.SOLUTION: A bearing mechanism has a slide member 42, which rotatably supports a rotary shaft 14 with an outer peripheral surface of the rotary shaft 14 slidably contacting therewith and thereby enabling the slide member 42 to support the rotary shaft 14, on an inner peripheral surface of a bearing case 41 having a cylindrical shape. The slide member 42 includes slide pieces 43 which protrude to the inner side in a radial direction and are provided along a circumferential direction. The slide member 42 is formed so that the slide pieces 43 protruding to the inner side in the radial direction are set to different protruding positions.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a bearing mechanism used for a pump such as an axial flow pump or a mixed flow pump, and a pump to which the bearing mechanism is applied.

  For example, Patent Document 1 discloses a pump in which a rotation axis is disposed along a vertical direction. This pump has a pumping pipe that extends vertically in the suction water tank, and a bend pipe in which the upper part of the pumping pipe is bent along the horizontal direction. And a rotating shaft is penetrated in the pumping pipe from the upper part, and the impeller is being fixed to the lower part. Therefore, when the rotary shaft is driven and rotated by the drive motor with the lower end opening of the pumping pipe submerged in water, the impeller rotates, so that the water flowing into the pumping pipe is pumped upward in the flow path. It is discharged through the bend pipe.

  Further, for example, Patent Documents 2 and 3 show that a sliding piece that is independent in the axial direction or the radial direction is provided as a sliding member that rotatably supports the rotating shaft.

JP 2001-132742 A Japanese Patent Laid-Open No. 5-126138 Japanese Patent Laid-Open No. 9-317763

  In the pump as shown in Patent Document 1, the rotation shaft rotates while being supported by the outer peripheral surface coming into contact with the inner peripheral surface of the sliding member fixed to the bearing side. At this time, due to imbalance such as imbalance of the impeller, the rotating shaft acts on the rotating shaft including the impeller in the radial direction, and on the outer peripheral surface, the acting direction of the centrifugal force is the sliding side on the bearing side. A revolving motion that slides with the moving member and the reaction direction of the centrifugal force does not slide with the sliding member, that is, a precession motion.

  In this case, the gap between the rotating shaft and the sliding member is different in the circumferential direction, and the gap gradually narrows toward the traveling direction of the turning motion in the sliding portion, while the gap is opposite to the traveling direction of the turning motion. Spread gradually. For this reason, different pressure (water pressure) distributions are generated in the circumferential direction by the rotation of water (fluid). Then, on the side where the gap gradually narrows, the pressure in the gap between the rotating shaft and the sliding member becomes a high (positive pressure) region, and the shaft center of the bearing that is opened from the center in the axial direction of the bearing. The water inside the bearing flows to the end of the direction and is discharged. On the other hand, on the side where the gap gradually widens, the pressure in the gap between the rotating shaft and the sliding member becomes a low (negative pressure) region, and the axial center of the bearing from the end in the axial direction of the opened bearing. The water outside the bearing flows into the central part of the direction and is taken in.

  Here, in particular, pumps installed in the sea or rivers contain foreign substances such as sand and shells in the water (seawater) when tsunamis are large or when a tsunami occurs during an earthquake. There is a possibility that foreign matters are taken into the bearing together with water due to the action. And when this foreign material accumulates between a rotating shaft and a sliding member, there exists a problem which a sliding member will wear abnormally. If there is such a problem, the clearance between the rotating shaft and the sliding member becomes large, the shaft vibration of the rotating shaft increases, and the pump becomes inoperable, or the operation of the plant where the pump is installed is hindered. There is a risk of teasing.

  This invention solves the subject mentioned above, and provides the bearing mechanism and pump which can suppress generation | occurrence | production of the abrasion of the sliding member by the foreign material taken in into the clearance gap between a rotating shaft and a sliding member. With the goal.

  In order to achieve the above-described object, the bearing mechanism of the present invention includes a sliding member that rotatably supports the rotating shaft by sliding the outer peripheral surface of the rotating shaft in sliding contact with the inner peripheral surface of a cylindrical bearing case. In the bearing mechanism, the sliding member has a plurality of sliding pieces that protrude inward in the radial direction and are provided along the circumferential direction, and the protruding positions of the sliding pieces inward in the radial direction are different. It is characterized by forming.

  When centrifugal force acts in the radial direction of the rotating shaft due to the effect of unbalance, the outer peripheral surface of the rotating shaft in the acting direction of the centrifugal force is in sliding contact with the sliding member of the bearing, and the outer peripheral surface in the reaction direction of the centrifugal force F is slid. The turning motion is such that it does not slide on the moving member. As a result, the clearance between the rotating shaft and the sliding member fluctuates in the circumferential direction, and a different pressure distribution is generated in the circumferential direction due to the fluid rotating with the rotating rotating shaft between the rotating shaft and the sliding member. To do. In other words, on the front side in the direction of travel of the rotating shaft, the gap gradually narrows and becomes a region where the pressure in the space between the rotating shaft and the sliding member is high. The gap gradually widens and becomes a region where the pressure in the gap between the rotating shaft and the sliding member is low. And in the area | region where a pressure is low, the foreign material contained in the fluid will enter into the clearance gap between a rotating shaft and a bearing side. In the present invention, the sliding piece whose radially inward protruding position is relatively close to the shaft center slides on the outer peripheral surface of the rotating shaft with respect to the sliding piece whose radially inward protruding position is relatively far from the axis. Since the sliding surfaces that come into contact are close, the gap between the sliding surface and the outer peripheral surface of the rotating shaft is narrowed. In this way, in a relatively narrow gap portion, it is difficult for foreign matter to enter, so that wear of the sliding surface is difficult to occur. As a result, it is possible to suppress the occurrence of wear of the sliding member due to the foreign matter taken into the gap between the rotating shaft and the bearing. In addition, the sliding life of the sliding piece whose projection position is relatively close to the shaft center is longer than the sliding piece whose projection position is relatively far from the shaft center, so that the wear life can be extended.

  In the bearing mechanism of the present invention, a plurality of the sliding pieces are provided at the same protruding position, and are arranged uniformly in the circumferential direction.

  According to this bearing mechanism, since each sliding piece is in sliding contact with the outer peripheral surface of the rotating shaft at an equal position, the rotating shaft can be stably supported.

  In the bearing mechanism of the present invention, the sliding piece is formed with a circumferential width different in the axial direction of the bearing case, the central portion in the axial direction has the maximum width, and both ends in the axial direction. The portion has the minimum width, and the taper surface is formed on the width end surface from the maximum width to the minimum width.

  According to this bearing mechanism, foreign matter is easily discharged along the tapered surface to both end sides in the axial direction of the bearing case. For this reason, it is possible to reduce the entry of foreign matter into the gap between the sliding surface of the sliding piece and the outer peripheral surface of the rotating shaft, and to reduce wear.

  In the bearing mechanism of the present invention, the tapered surface is formed in the rotation direction of the rotating shaft.

  According to this bearing mechanism, since the flow of water that is accompanied by the rotation of the rotating shaft faces the tapered surface, foreign matters are more easily discharged by the tapered surface. For this reason, it is possible to further reduce the entry of foreign matter into the gap between the sliding surface of the sliding piece and the outer peripheral surface of the rotating shaft, thereby further reducing wear.

  In the bearing mechanism of the present invention, the sliding piece is characterized in that a groove communicating in the circumferential direction is formed on a sliding surface slidably contacting the rotating shaft.

  According to this bearing mechanism, foreign matter enters the groove, so that foreign matter can be reduced from entering the gap between the sliding surface of the sliding piece and the outer peripheral surface of the rotating shaft, and wear can be reduced. .

  In the bearing mechanism of the present invention, the sliding piece having a maximum radially inward protruding position is urged radially inward by an elastic force.

  According to this bearing mechanism, the sliding surface with the maximum protruding position radially inward is urged radially inward by the elastic force, so that the sliding surface is pressed against the outer peripheral surface of the rotating shaft. For this reason, since the clearance gap between the sliding face of the said sliding piece and the outer peripheral surface of a rotating shaft is lose | eliminated, the penetration | invasion of the foreign material to the said clearance gap can be suppressed and abrasion can be reduced. Moreover, since the sliding piece having the maximum protruding position radially inward is urged radially inward by the elastic force, the wear margin of the sliding piece increases, so the wear life can be extended. it can. Moreover, even if a foreign object enters the gap between the sliding surface of the sliding piece whose maximum inward projecting position in the radial direction and the outer peripheral surface of the rotary shaft, the sliding piece has a radius against the elastic force. It can move to the outside in the direction, and seizure between the sliding surface of the sliding piece and the outer peripheral surface of the rotating shaft can be avoided.

  In the bearing mechanism of the present invention, an elastic force that biases the sliding piece is generated by a coil spring.

  According to this bearing mechanism, an elastic force that biases the sliding piece can be obtained by using the coil spring.

  Further, the bearing mechanism of the present invention is characterized in that an elastic force that urges the sliding piece is generated by a leaf spring formed by bending or bending.

  According to this bearing mechanism, an elastic force that biases the sliding piece can be obtained by using a leaf spring formed by bending or bending.

  Further, the bearing mechanism of the present invention is characterized in that an elastic force that biases the sliding piece is generated by a leaf spring continuously formed in the axial direction in a wave shape or a zigzag shape.

  According to this bearing mechanism, an elastic force that biases the sliding piece can be obtained by using a leaf spring continuously formed in the axial direction in a wave shape or a zigzag shape.

  In order to achieve the above-described object, the pump of the present invention includes a casing, and a bearing having a sliding member that rotatably supports the rotating shaft by slidingly contacting an outer peripheral surface of the rotating shaft inside the casing; A pump having an impeller provided on the rotating shaft includes the bearing mechanism described in any one of the above.

  According to this pump, the effect of suppressing the occurrence of wear of the sliding member due to foreign matter can be obtained. As a result, the operation as a pump can be performed stably, and the influence on the installed plant can be reduced.

  According to the present invention, it is possible to suppress the occurrence of wear of the sliding member due to the foreign matter taken into the gap between the rotating shaft and the bearing.

FIG. 1 is a schematic configuration diagram of a pump to which a bearing mechanism according to an embodiment of the present invention is applied. FIG. 2 is a sectional view of a general bearing mechanism. 3 is a sectional view taken along line III-III in FIG. FIG. 4 is an explanatory diagram showing the pressure distribution in the circumferential direction in a general bearing mechanism. FIG. 5 is an explanatory diagram showing an axial pressure distribution at a positive pressure position in a general bearing mechanism. FIG. 6 is an explanatory diagram showing an axial pressure distribution at a negative pressure position in a general bearing mechanism. FIG. 7 is a cross-sectional view of the bearing mechanism according to Embodiment 1 of the present invention. 8 is a sectional view taken along line VIII-VIII in FIG. FIG. 9 is a partially enlarged view of FIG. FIG. 10 is a side view of a sliding piece in the bearing mechanism according to the second embodiment of the present invention. FIG. 11 is a cross-sectional view of a bearing mechanism according to Embodiment 3 of the present invention. 12 is a cross-sectional view taken along line XII-XII in FIG. FIG. 13 is a partially enlarged view of FIG. FIG. 14 is a cross-sectional view of a bearing mechanism according to Embodiment 4 of the present invention. 15 is a cross-sectional view taken along the line XV-XV in FIG. FIG. 16 is a partially enlarged view of FIG. FIG. 17 is a cross-sectional view of a bearing mechanism according to Embodiment 5 of the present invention. 18 is a sectional view taken along line XVIII-XVIII in FIG. FIG. 19 is a cross-sectional view of a bearing mechanism according to Embodiment 6 of the present invention.

  Embodiments according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

  FIG. 1 is a schematic configuration diagram of a pump to which a bearing mechanism according to this embodiment is applied. The pump in this embodiment is, for example, a vertical shaft mixed flow pump 10 as shown in FIG. The mixed flow pump 10 includes a casing 13 provided with a suction port 11 and a discharge port 12, a rotating shaft 14 disposed in the casing 13, an impeller 15 fixed to the lower portion of the rotating shaft 14, And bearings 16 and 17 that rotatably support the rotating shaft 14.

  The casing 13 has a cylindrical shape and is arranged along a vertical direction on a mounting base (not shown). In the casing 13, for example, first, second, and third casings 21, 22, and 23 are connected in series in the vertical direction from above. The suction port 11 is formed by fixing the suction bell 24 to the third casing 23 on the lower end side. Moreover, the discharge port 12 is formed in the casing 13 toward the side part by the upper part of the first casing 21 on the upper end side being curved in the horizontal direction. A discharge pipe 25 is connected to the discharge port 12 of the first casing 21. Therefore, the casing 13 has a first flow path A that extends substantially vertically from the suction port 11 and a second flow path B that curves from the first flow path A to the discharge port 12 in a substantially horizontal direction.

  The casing 13 has a rotating shaft 14 disposed therein. The rotating shaft 14 is rotatably supported by a plurality of bearings 16 and 17. The bearing 16 is supported by a bearing box 28 supported by a plurality of stays 26 extending from the casing 13. The bearing 17 is supported by a bearing box 29 supported by a plurality of stays 27 extended from the casing 13. An impeller 15 is fixed to the lower end of the rotary shaft 14. The rotating shaft 14 is connected to a driving device (motor and speed reducer) 30 at an upper end portion extending from the curved portion of the first casing 21 on the upper end side to the outside of the casing 13. The casing 13 has a diffuser (not shown) fixed to the inner peripheral wall of the third casing 23 on the lower end side, above the impeller 15.

  Therefore, when the driving device 30 is driven, the rotational force is transmitted to the rotating shaft 14 and rotates. Then, the impeller 15 fixed to the lower end part of the rotating shaft 14 rotates with the rotating shaft 14, and the pressure in the casing 13, that is, the pressure in the first flow path A rises, so that water (fluid) is sucked into the suction port. 11 is sucked into the casing 13. Then, the water sucked into the casing 13 flows upward in the vertical direction in the first flow path A, flows in the horizontal direction in the second flow path B after the pressure is reduced by the diffuser, and is discharged from the discharge port 12 to the discharge pipe 25. Discharged.

  Such a mixed flow pump 10 is used, for example, for transferring seawater for cooling equipment in a nuclear power plant or a thermal power plant, but may be used for other purposes.

  Here, a general bearing mechanism in which the rotating shaft 14 is rotatably supported with respect to the bearings 16 and 17 described above will be described. However, since the bearings 16 and 17 have the same configuration, only the bearing 16 side will be described.

  FIG. 2 is a sectional view of a general bearing mechanism. 3 is a sectional view taken along line III-III in FIG. FIG. 4 is an explanatory diagram showing the pressure distribution in the circumferential direction in a general bearing mechanism. FIG. 5 is a cross-sectional view taken along the line IV-V in FIG. 4 and is an explanatory diagram showing an axial pressure distribution at a positive pressure position in a general bearing mechanism. FIG. 6 is a cross-sectional view taken along the line IV-VI in FIG. 4 and is an explanatory diagram showing an axial pressure distribution at a negative pressure position in a general bearing mechanism.

  As shown in FIGS. 2 and 3, the bearing 16 includes a bearing case 41 and a sliding member 42. The bearing case 41 is formed in a cylindrical shape. The sliding member 42 is provided inside the bearing case 41 and along the inner peripheral surface. Although this sliding member 42 may be arrange | positioned at all the inner peripheral surfaces of the bearing case 41, it is predetermined in the circumferential direction on the inner peripheral surface of the bearing case 41 as several sliding pieces 43 (refer FIG. 4). It may be fixed at an interval (preferably an equal interval). The sliding member 42 (sliding piece 43) is made of rubber or synthetic resin, and its outer peripheral surface is bonded to the inner peripheral surface of the bearing case 41, and the outer peripheral surface of the cylindrical rotating shaft 14 is formed on the inner peripheral surface. A sliding surface 44 that can support the rotating shaft 14 is formed by the sliding contact of the surfaces. In this case, the bearing case 41 and the sliding member 42 (sliding piece 43) are formed to be concentric with the axis O. The rotating shaft 14 is arranged so as to be basically concentric with respect to the axis O, but the outer peripheral surface and the sliding surface 44 of the sliding member 42 (sliding piece 43) are allowed to rotate. A slight gap C is formed between the two. 2 and 3, the gap C is exaggerated.

  When the rotating shaft 14 is supported by the bearing 16 in water and rotates, the outer peripheral surface is supported by contacting the sliding surface 44 of the sliding member 42. At this time, the centrifugal force F (see FIG. 4) acts in the radial direction of the rotating shaft 14 due to the imbalance such as imbalance of the impeller 15, so that the clearance C between the rotating shaft 14 and the sliding member 42 is increased. The pressure varies in the circumferential direction, and water is rotated by the rotating rotating shaft 14 between the rotating shaft 14 and the sliding surface 44 of the sliding member 42 to generate different pressure distributions in the circumferential direction.

  That is, as shown in FIG. 4, the rotating shaft 14 rotates while being supported by the outer peripheral surface coming into contact with the sliding surface 44 of each sliding piece 43. At this time, due to the centrifugal force F, the outer peripheral surface in the direction of action of the centrifugal force F is in sliding contact with the sliding piece 43, and the outer peripheral surface in the direction of reaction of the centrifugal force F is in sliding contact with the sliding piece 43. Turning motion, that is, precession motion. When the rotary shaft 14 turns, the gap C with the sliding piece 43 fluctuates in the circumferential direction, and the gap C gradually narrows toward the traveling direction S of the turning motion at the sliding portion, while the turning direction 14 On the opposite side, the gap C gradually widens. For this reason, water rotates with the rotation of the rotating shaft 14. Then, different pressure (water pressure) distributions are generated in the circumferential direction. That is, when the rotary shaft 14 turns in the direction of arrow S in FIG. 4, the pressure in the gap C between the rotary shaft 14 and the sliding piece 43 is high (positive pressure P1) on the side where the gap C gradually narrows. On the side where the pressure gradually spreads, the pressure in the gap C between the rotating shaft 14 and the sliding piece 43 becomes low (negative pressure P2).

  Therefore, in the region where the pressure in the gap C between the rotating shaft 14 and the sliding piece 43 is high (positive pressure P1), as shown in FIG. 5, the shaft center O direction in the bearing 16 (the direction in which the shaft center O extends). From the central part of the bearing 16, the water in the bearing 16 flows and is discharged as indicated by the arrow from the open end of the axis O direction. On the other hand, in the region where the pressure in the gap C between the rotating shaft 14 and the sliding piece 43 is low (negative pressure P2), as shown in FIG. The water outside the bearing 16 flows and is taken into the center of the shaft 16 in the direction of the axis O as indicated by the arrow.

  If the water (seawater) in the sea or river where the mixed flow pump 10 is installed contains a lot of foreign matters such as sand and shells, the foreign matter is taken into the bearing 16 together with the water. Then, if the foreign matter is not discharged in the positive pressure P1 region where the pressure is high and accumulates in the gap C, the foreign matter is caught in the gap C between the rotating shaft 14 and the sliding piece 43, and the outer peripheral surface of the rotating shaft 14 or sliding The sliding surface 44 of the piece 43 will be abnormally worn.

[Embodiment 1]
FIG. 7 is a cross-sectional view of the bearing mechanism according to the present embodiment. 8 is a sectional view taken along line VIII-VIII in FIG. FIG. 9 is a partially enlarged view of FIG. In the present embodiment, the same components as those in the general bearing mechanism described above are denoted by the same reference numerals and description thereof is omitted.

  In the bearing mechanism of the present embodiment, a sliding piece 43 is provided for the sliding member 42 of the bearing 16. The sliding piece 43 protrudes inward in the radial direction of the bearing case 41, and the sliding surface 44, which is the protruding end, slidably contacts the outer peripheral surface of the rotating shaft 14, thereby supporting the rotating shaft 14 rotatably. A plurality are provided along the direction. The sliding piece 43 is continuously provided along the direction of the axis O. The sliding piece 43 is a protruding position inward in the radial direction, and is formed by changing the position of the sliding surface 44. Specifically, the sliding piece 43 is provided with a plurality of types (two types in this embodiment) of the first sliding piece 43A and the second sliding piece 43B having different distances of the sliding surface 44 with respect to the axis O. ing. The sliding surface 44 of the first sliding piece 43A has a shorter distance to the axis O than the sliding surface 44 of the second sliding piece 43B. That is, the first sliding piece 43A slides on the outer peripheral surface of the rotating shaft 14 by the position of the sliding surface 44 that comes into sliding contact with the outer peripheral surface of the rotating shaft 14 approaching the second sliding piece 43B. The gap C with the surface 44 is narrower than that of the second sliding piece 43B.

  Further, a plurality of first sliding pieces 43A and second sliding pieces 43B are provided, and are equally arranged in the circumferential direction. In FIG. 7, four first sliding pieces 43A and two second sliding pieces 43B are provided at intervals of 90 ° in the circumferential direction. The number of the first sliding pieces 43A and the second sliding pieces 43B is not particularly limited, but it is preferable that at least three are provided to support the rotating shaft 14. Further, the first sliding piece 43A and the second sliding piece 43B may not be the same number.

  Moreover, the recessed part 45 is formed in the meantime by providing each sliding piece 43 protrudingly. A plurality of the recesses 45 are formed by providing a plurality of sliding pieces 43, and the groove bottom position (radial distance from the bearing case 41 or the axis O) is the circumferential direction and the axis O direction in this embodiment. All are in the same position. The recess 45 may be provided with a groove bottom position that is different in the circumferential direction or the axis O direction.

  As described above, the bearing mechanism of the present embodiment has the sliding member 42 that rotatably supports the rotating shaft 14 by the sliding contact of the outer peripheral surface of the rotating shaft 14 with the inner peripheral surface of the cylindrical bearing case 41. It is a bearing mechanism. The sliding member 42 has a plurality of sliding pieces 43 that protrude inward in the radial direction and are provided along the circumferential direction, and are formed with different protruding positions inward in the radial direction of the sliding pieces 43. Has been.

  According to this bearing mechanism, the first sliding piece 43A whose radially inward protruding position is relatively close to the axis O is the second sliding piece whose radial inward protruding position is relatively far from the axis O. Since the sliding surface 44 that is in sliding contact with the outer peripheral surface of the rotating shaft 14 is closer to 43B, the gap C between the sliding surface 44 and the outer peripheral surface of the rotating shaft 14 becomes narrower. In this way, in the relatively narrow gap C, it is difficult for foreign matter to enter, so that the sliding surface 44 is less likely to be worn. As a result, it is possible to suppress the wear of the sliding member 42 due to the foreign matter taken into the gap C between the rotating shaft 14 and the bearing 16. In addition, the first sliding piece 43A, whose protruding position is relatively close to the axis O, has a large wear allowance compared to the second sliding piece 43B, whose protruding position is relatively far from the axis O, so the wear life is increased. can do.

  Further, in the bearing mechanism of the present embodiment, the sliding piece 43 is provided with a plurality of first sliding pieces 43A and second sliding pieces 43B at the same protruding position, and each is equally arranged in the circumferential direction.

  According to this bearing mechanism, since each sliding piece 43 is in sliding contact with the outer peripheral surface of the rotating shaft 14 at an equal position, the rotating shaft 14 can be stably supported.

[Embodiment 2]
FIG. 10 is a side view of the sliding piece in the bearing mechanism according to the present embodiment. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the bearing mechanism of the present embodiment, the sliding pieces 43 (43A, 43B) are formed with different circumferential widths in the direction of the axis O of the bearing case 41. Specifically, the sliding piece 43 (43A, 43B) has a central portion in the direction of the axis O having the maximum width and both ends in the direction of the axis O having the minimum width, and the concave portion 45 extending from the maximum width to the minimum width. A tapered surface 46 is formed on the width end surface facing the side.

  According to this bearing mechanism, the sliding piece 43 (43A, 43B) has a maximum width in the central portion in the axial center O direction and a minimum width in both ends in the axial center O direction. Since the taper surface 46 is formed on the width end surface from the minimum width to the minimum width, foreign matter is easily discharged along the taper surface 46 to both end sides of the bearing case 41 in the axis O direction. For this reason, it is possible to reduce the entry of foreign matter into the gap C between the sliding surface 44 of the sliding piece 43 (43A, 43B) and the outer peripheral surface of the rotating shaft 14, and to reduce wear.

  Further, in the bearing mechanism of this embodiment, the tapered surface 46 is formed toward the rotation direction of the rotary shaft 14.

  According to this bearing mechanism, the flow of water that rotates with the rotation of the rotary shaft 14 faces the tapered surface 46, so that foreign matters are more easily discharged by the tapered surface 46. For this reason, it is possible to reduce the entry of foreign matter into the gap C between the sliding surface 44 of the sliding piece 43 (43A, 43B) and the outer peripheral surface of the rotary shaft 14, thereby further reducing wear.

[Embodiment 3]
FIG. 11 is a cross-sectional view of the bearing mechanism according to the present embodiment. 12 is a cross-sectional view taken along line XII-XII in FIG. FIG. 13 is a partially enlarged view of FIG. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the bearing mechanism of the present embodiment, the sliding piece 43 (43A, 43B) is formed with a groove 47 communicating in the circumferential direction on the sliding surface 44 slidably contacting the rotating shaft 14. The groove 47 communicates the recesses 45 formed on both sides in the circumferential direction of each sliding piece 43 (43A, 43B). A plurality of grooves 47 are provided in the direction of the axis O of the bearing case 41.

  According to this bearing mechanism, foreign matter enters the groove 47, so that foreign matter is less likely to enter the gap C between the sliding surface 44 of the sliding piece 43 (43A, 43B) and the outer peripheral surface of the rotary shaft 14. And wear can be reduced.

  In FIG. 13, it has shown as a structure which has the taper surface 46 demonstrated in Embodiment 2 mentioned above. In this way, by providing the groove 47 together with the tapered surface 46, foreign matter can be reduced from entering the gap C between the sliding surface 44 of the sliding piece 43 (43 </ b> A, 43 </ b> B) and the outer peripheral surface of the rotary shaft 14. And wear can be further reduced. In addition, in this embodiment, the structure which does not have the taper surface 46 is also included.

[Embodiment 4]
FIG. 14 is a cross-sectional view of the bearing mechanism according to the present embodiment. 15 is a cross-sectional view taken along the line XV-XV in FIG. FIG. 16 is a partially enlarged view of FIG. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the bearing mechanism of the present embodiment, the sliding piece 43 having the maximum protruding position inward in the radial direction (the first sliding piece 43A in the present embodiment) is urged radially inward by elastic force. ing.

  Specifically, the coil spring 51 generates an elastic force that biases the first sliding piece 43 </ b> A radially inward. The coil spring 51 is a compression coil spring, and is disposed between the independently formed first sliding piece 43A and the inner peripheral surface of the bearing case 41, and the first sliding piece 43A is attached to the inside in the radial direction. Rush. A plurality of coil springs 51 (five in this embodiment) are provided along the direction of the axis O of the bearing case 41. Further, the first sliding piece 43A is provided with a contact plate 52 on the radially outer side pressed by the coil spring 51 so that the urging force of the coil spring 51 acts evenly in the direction of the axis O or the circumferential direction.

  According to the bearing mechanism configured as described above, the first sliding piece 43A having the maximum protruding position radially inward is urged radially inward by the elastic force of the coil spring 51, so that the sliding surface 44 is pressed against the outer peripheral surface of the rotating shaft 14. For this reason, since there is no gap C between the sliding surface 44 of the first sliding piece 43A and the outer peripheral surface of the rotating shaft 14, it is possible to suppress the entry of foreign matter into the gap C and reduce wear. it can. Moreover, the first sliding piece 43A having the maximum radially inward protruding position is biased radially inward by the elastic force of the coil spring 51, so that the wear amount of the first sliding piece 43A increases. Therefore, the wear life can be extended. Moreover, even if foreign matter enters the gap C between the sliding surface 44 of the first sliding piece 43A and the outer peripheral surface of the rotary shaft 14, the first sliding piece 43A has a radius against the elastic force of the coil spring 51. It can move to the outside in the direction, and seizure between the sliding surface 44 of the first sliding piece 43A and the outer peripheral surface of the rotating shaft 14 can be avoided.

  In addition, the structure of this embodiment can acquire a more remarkable effect by including the structure of Embodiment 2 and Embodiment 3 mentioned above.

[Embodiment 5]
FIG. 17 is a cross-sectional view of the bearing mechanism according to the present embodiment. 18 is a sectional view taken along line XVIII-XVIII in FIG. In the present embodiment, the same components as those in the first embodiment and the fourth embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  In the bearing mechanism of the present embodiment, the sliding piece 43 having the maximum protruding position inward in the radial direction (the first sliding piece 43A in the present embodiment) is urged radially inward by elastic force. ing.

  Specifically, an elastic force that biases the first sliding piece 43 </ b> A radially inward is generated by the leaf spring 53. The plate spring 53 is formed by bending or bending a plate-shaped spring material, and is disposed between the independently formed first sliding piece 43A and the inner peripheral surface of the bearing case 41, and the first sliding member The moving piece 43A is biased radially inward. A plurality (two in this embodiment) of the leaf springs 53 are provided along the axis O direction of the bearing case 41. Further, the first sliding piece 43A is provided with a contact plate 52 on the radially outer side pressed by the plate spring 53 so that the urging force by the plate spring 53 acts evenly in the axial center O direction and the circumferential direction. Yes.

  According to the bearing mechanism configured as described above, the first sliding piece 43A having the maximum protruding position radially inward is urged radially inward by the elastic force of the leaf spring 53, thereby sliding. The surface 44 is pressed against the outer peripheral surface of the rotating shaft 14. For this reason, since there is no gap C between the sliding surface 44 of the first sliding piece 43A and the outer peripheral surface of the rotating shaft 14, it is possible to suppress the entry of foreign matter into the gap C and reduce wear. it can. Moreover, since the first sliding piece 43A having the maximum protruding position radially inward is urged radially inward by the elastic force of the leaf spring 53, the wear amount of the first sliding piece 43A is large. Therefore, the wear life can be extended. In addition, even if foreign matter enters the gap C between the sliding surface 44 of the first sliding piece 43A and the outer peripheral surface of the rotary shaft 14, the first sliding piece 43A resists the elastic force of the leaf spring 53. It can move radially outward, and seizure between the sliding surface 44 of the first sliding piece 43A and the outer peripheral surface of the rotating shaft 14 can be avoided.

  In addition, the structure of this embodiment can acquire a more remarkable effect by including the structure of Embodiment 2 and Embodiment 3 mentioned above.

[Embodiment 6]
FIG. 19 is a cross-sectional view of the bearing mechanism according to the present embodiment. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the bearing mechanism of the present embodiment, the sliding piece 43 having the maximum protruding position inward in the radial direction (the first sliding piece 43A in the present embodiment) is urged radially inward by elastic force. ing.

  Specifically, an elastic force that urges the first sliding piece 43 </ b> A radially inward is generated by the leaf spring 54. The plate spring 54 is formed between a first sliding piece 43 </ b> A, which is formed of a plate-shaped spring material continuously in the direction of the axis O in a wavy or zigzag shape, and the inner peripheral surface of the bearing case 41. It arrange | positions and urges | biass the 1st sliding piece 43A to radial inside. Further, the first sliding piece 43A is provided with a contact plate 52 on the radially outer side pressed by the plate spring 54 so that the urging force by the plate spring 54 acts evenly in the direction of the axis O or the circumferential direction. Yes.

  According to the bearing mechanism configured as described above, the first sliding piece 43A having the maximum protruding position radially inward is urged radially inward by the elastic force of the leaf spring 54, thereby sliding. The surface 44 is pressed against the outer peripheral surface of the rotating shaft 14. For this reason, since there is no gap C between the sliding surface 44 of the first sliding piece 43A and the outer peripheral surface of the rotating shaft 14, it is possible to suppress the entry of foreign matter into the gap C and reduce wear. it can. Moreover, since the first sliding piece 43A having the maximum protruding position radially inward is urged radially inward by the elastic force of the leaf spring 54, the wear amount of the first sliding piece 43A is large. Therefore, the wear life can be extended. In addition, even if foreign matter enters the gap C between the sliding surface 44 of the first sliding piece 43A and the outer peripheral surface of the rotating shaft 14, the first sliding piece 43A resists the elastic force of the leaf spring 54. It can move radially outward, and seizure between the sliding surface 44 of the first sliding piece 43A and the outer peripheral surface of the rotating shaft 14 can be avoided.

  In addition, the structure of this embodiment can acquire a more remarkable effect by including the structure of Embodiment 2 and Embodiment 3 mentioned above.

  In addition, according to the pump (diagonal flow pump 10) to which the bearing mechanism of each embodiment mentioned above is applied, the effect which suppresses generation | occurrence | production of the abrasion by the side of the rotating shaft 14 or the bearing 16 by a foreign material can be acquired. As a result, the operation as a pump can be performed stably, and the influence on the installed plant can be reduced.

DESCRIPTION OF SYMBOLS 10 Diagonal flow pump 11 Suction port 12 Discharge port 13 Casing 14 Rotating shaft 15 Impeller 16, 17 Bearing 21 First casing 22 Second casing 23 Third casing 24 Suction bell 25 Exhaust pipe 26 Stay 27 Stay 28 Bearing box 29 Bearing box Reference Signs List 30 drive device 41 bearing case 42 sliding member 43 sliding piece 43A first sliding piece 43B second sliding piece 44 sliding surface 45 recess 46 taper surface 47 groove 51 coil spring 52 current plate 53 plate spring 54 plate spring A first One flow path B Second flow path C Clearance F Centrifugal force O Axis center P1 Positive pressure P2 Negative pressure S Traveling direction of swivel motion

Claims (10)

In the bearing mechanism having a sliding member that rotatably supports the rotating shaft by sliding the outer peripheral surface of the rotating shaft in sliding contact with the inner peripheral surface of the cylindrical bearing case,
The sliding member has a plurality of sliding pieces that protrude inward in the radial direction and are provided along the circumferential direction, and are formed with different protruding positions inward in the radial direction of the sliding pieces. Bearing mechanism.   2. The bearing mechanism according to claim 1, wherein a plurality of the sliding pieces are provided at the same protruding position and are equally arranged in the circumferential direction.   The sliding pieces are formed with different circumferential widths in the axial direction of the bearing case, the central portion in the axial direction is the maximum width, and both end portions in the axial direction are the minimum width, The bearing mechanism according to claim 1, wherein a taper surface is formed on a width end surface from a large width to a minimum width.   The bearing mechanism according to claim 3, wherein the tapered surface is formed toward a rotation direction of the rotation shaft.   The bearing mechanism according to any one of claims 1 to 4, wherein the sliding piece is formed with a groove communicating with a circumferential direction on a sliding surface that is in sliding contact with the rotating shaft.   6. The sliding piece according to claim 1, wherein the sliding piece having a maximum protruding position radially inward is urged radially inward by an elastic force. Bearing mechanism.   The bearing mechanism according to claim 6, wherein an elastic force that biases the sliding piece is generated by a coil spring.   The bearing mechanism according to claim 6, wherein an elastic force that biases the sliding piece is generated by a leaf spring formed by bending or bending.   The bearing mechanism according to claim 6, wherein an elastic force that urges the sliding piece is generated by a leaf spring continuously formed in the axial direction in a wave shape or a zigzag shape. In a pump having a casing, a bearing having a sliding member that rotatably supports the rotating shaft by slidingly contacting an outer peripheral surface of the rotating shaft inside the casing, and an impeller provided on the rotating shaft ,
A pump comprising the bearing mechanism according to claim 1.

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