JP6646635B2 - Cooling pipe protection structure and fully enclosed fan-shaped rotating electric machine - Google Patents

Description

  The present invention relates to a cooling pipe protection structure and a fully-closed external fan-type rotating electric machine using the same.

  The rotating electric machine includes a rotor and a stator, and these are often housed in a frame. A cooling gas, such as air, in the frame is typically driven by an internal fan attached to the rotor shaft of the rotor to cool the rotor and stator in the frame.

  Regarding the release of the heat generated in the frame to the outside of the machine, there are a system using natural heat radiation from the outer surface of the frame and a system using forced cooling. In the system using forced cooling, a water cooling system or the like is used when the heat load is large, but in other cases, a cooling system using outside air is often used. The cooling by the outside air may be performed by a separate fan. However, there are many systems in which an outside fan is provided in a portion of the rotor shaft on the side opposite to the frame outside the frame and the rotor shaft is forcibly cooled by the outside air. In the case of cooling with outside air, a method of sending outside air to the outer surface of the frame on which the fins are attached, and a method of cooling by sending outside air to the inside of the cooling pipe by providing a cooling pipe penetrating the atmosphere of a cooling gas in the machine ( (See Patent Document 1).

JP 2004-254438 A Japanese Patent No. 4754959

  The cooling method of sending outside air to the outer surface of the frame involves heat exchange through the frame. On the other hand, in the case of the cooling method using the cooling pipe, the cooling through the cooling pipe, which is thinner than the frame, and the point at which the flow rate of the outside air in the cooling pipe is faster, compared with the method of cooling the outer surface of the frame. Efficient.

  On the other hand, since the outside air contains dust, salt, and the like to varying degrees, in the case of a thin wall such as a cooling pipe, corrosion near the inlet of the cooling pipe becomes a problem. Although it depends on the flow rate of the outside air, in many cases, dust and salt are accumulated at the bottom inside the cooling pipe within a range of about 10 cm from the inlet of the cooling pipe, leading to corrosion. In addition, in a cooling pipe using a wound pipe instead of a seamless pipe, there is a problem that the possibility of further occurrence of corrosion in the vertical welded portion increases, especially when the vertical welded portion is near the bottom. .

  Regarding corrosion, in the case of a heat exchanger that performs indirect heat exchange between a high-temperature gas containing a corrosive component and moisture and a low-temperature fluid, a structure for preventing the occurrence of low-temperature corrosion due to dew condensation by the low-temperature fluid is adopted. It has been proposed (see Patent Document 2). In this example, the structure is complicated because it is intended for use under special circumstances.

  An object of the present invention is to suppress corrosion of a cooling pipe that allows outside air to pass through, without using a complicated structure, in a fully enclosed external fan-type rotating electric machine.

In order to achieve the above object, the present invention provides a rotor having a rotor shaft extending in the rotation axis direction and rotatably supported, and a rotor core provided radially outside the rotor shaft. A stator having a cylindrical stator core provided radially outward of a rotor core, a stator winding penetrating the stator core in the direction of the rotation axis, and a stator having a radial direction. A frame that is disposed outside and stores the rotor core and the stator, and a connection-side bearing and an anti-connection-side bearing that support the rotor shaft on both sides in the rotation axis direction with the rotor core interposed therebetween, A connecting-side bearing bracket and an anti-connecting-side bearing bracket that fixedly support each of the connecting-side bearing and the anti-connecting-side bearing and that are connected to both ends in the rotation axis direction of the frame, and extend in the rotation axis direction; A plurality of cooling pipes arranged in parallel, an inlet pipe sheet and an outlet pipe sheet supporting each of the ends of the plurality of cooling pipes and coupling with each of the plurality of cooling pipes at a joint, A cooler cover that houses a cooling pipe and forms a closed space together with the frame, the connection-side bearing bracket, the anti-connection-side bearing bracket, the inlet tube plate, and the outlet tube plate, and is provided on each of the coupling portions. A cooler having a detachable cooling pipe protection structure, and an inner fan mounted on the rotor shaft between the connection side bearing and the opposite connection side bearing to drive cooling gas in the closed space. An external fan attached to an outside of the rotor shaft in the axial direction of the anti-connection side bearing and supplying outside air to the inside of each of the plurality of cooling pipes. tube Mamoru structure, and the cooling pipe tubular protective portion that extends to a predetermined position on the upstream side of the outlet of the cooling tube in said rotational axis direction along a respective inner surfaces of said plurality of cooling pipes in the mounted state of the protective structure A holding portion having an opening formed at the center thereof for restraining the movement of the protection portion in the direction of the rotation axis in combination with the protection portion and having an annular groove formed on a surface on the side where the protection portion is provided. It is characterized by the following.

Further, the cooling pipe protection structure according to the present invention includes a cooling pipe through which a cooling medium passes, and an inlet tube plate and an outlet pipe which respectively support an inlet-side end and an outlet-side end of the cooling pipe. A cooling pipe protection structure for protecting an inner surface on the inlet side of the cooling pipe at a connection portion between the cooling pipe and the inlet pipe plate of a cooler having a cooling plate , wherein the cooling is performed in an attached state of the cooling pipe protection structure. A cylindrical protection portion extending in the axial direction of the cooling pipe along an inner surface of the tube; and an opening formed at a center for coupling with the protection portion and restraining the movement of the protection portion in the axial direction, and the protection portion is provided. And a holding portion having an annular groove formed on the surface on the side of the holding member.

  ADVANTAGE OF THE INVENTION According to this invention, the corrosion of the cooling pipe which allows outside air to pass can be suppressed in a fully-closed external fan-type rotary electric machine without depending on a complicated structure.

It is an elevation sectional view showing the composition of the fully enclosed fan-type rotary electric machine concerning a 1st embodiment. FIG. 2 is a partial vertical cross-sectional view showing a configuration near an inlet of a cooling pipe of the fully-closed external fan-type rotary electric machine according to the first embodiment. FIG. 2 is a partial vertical cross-sectional view showing a method of forming a support tube portion in an inlet tube plate of the fully enclosed fan-shaped rotary electric machine according to the first embodiment. It is a partial longitudinal section showing a modification of a formation system of a support pipe part in an entrance tube sheet of a fully-closed outer fan type rotary electric machine concerning a 1st embodiment. It is a partial longitudinal section showing the composition near the entrance of the cooling pipe of the fully enclosed fan-shaped rotary electric machine according to the second embodiment. It is a partial longitudinal section showing the composition near the entrance of the cooling pipe of the fully enclosed fan-shaped rotary electric machine according to the third embodiment. It is a fragmentary longitudinal section showing the modification of the composition near the entrance of the cooling pipe of the fully enclosed fan-type rotary electric machine concerning a 3rd embodiment. It is a partial longitudinal section showing the composition in the case where the connection system of the cooling pipe and the inlet tube sheet of the fully enclosed fan-type rotary electric machine concerning a 3rd embodiment differs.

  Hereinafter, with reference to the drawings, a fully-closed external fan-type rotating electric machine according to an embodiment of the present invention will be described. Here, the same or similar parts are denoted by the same reference numerals, and redundant description will be omitted.

[First Embodiment]
FIG. 1 is an elevational sectional view showing the configuration of the fully-closed external fan-type rotating electric machine according to the first embodiment. The fully enclosed fan-shaped rotary electric machine 200 includes a rotor 10, a stator 20, a frame 40, a non-connection side bearing 30a, a connection side bearing 30b, a non-connection side bearing bracket 45a, a connection side bearing bracket 45b, and a cooler 60.

  The rotor 10 has a rotor shaft 11 extending horizontally in the direction of the rotation axis (hereinafter, referred to as an axial direction), and a rotor core 12 provided radially outside the rotor shaft 11.

  One end of the rotor shaft 11 in the axial direction is a connection target, that is, a load to be driven if the fully-closed external fan-shaped rotary electric machine 200 is a motor, or a connection to a prime mover if the fully-closed external fan-type rotary electric machine 200 is a generator. A portion 11a is formed. Hereinafter, in the axial direction, the direction of the connection portion 11a is referred to as a connection side, and the opposite direction is referred to as an anti-connection side.

  The rotor shaft 11 is rotatably supported by the non-connection side bearing 30a and the connection side bearing 30b. An inner fan 51a is mounted on the inside of the anti-connection side bearing 30a, and an inner fan 51b is mounted on the inside of the connection side bearing 30b, with the rotor core 12 interposed therebetween in the rotor shaft 11 in the axial direction. An external fan 55 that supplies outside air is provided outside the anti-connection side bearing 30a of the rotor shaft 11 in the axial direction to cool the fully enclosed external fan type rotary electric machine 200 by itself. An outer fan cover 56 is attached so as to cover the outer fan 55. The outer fan cover 56 is formed with an outside air inlet 56a for taking in outside air.

  The stator 20 has a cylindrical stator core 21 provided radially outside the rotor core 12 via a gap 18, and a portion near the radially inner surface of the stator core 21 at intervals in the circumferential direction. A stator winding 22 extends through a plurality of axially extending slots (not shown).

  The frame 40 surrounds the stator 20 and the rotor core 12 in a radial direction so as to house them. An anti-connection side bearing bracket 45a and a connection side bearing bracket 45b are provided on both sides of the frame 40 in the rotation axis direction. The anti-connection side bearing bracket 45a and the connection side bearing bracket 45b statically support the anti-connection side bearing 30a and the connection side bearing 30b, respectively.

  The frame 40 has a rectangular parallelepiped outer shape as a whole, and a cooler 60 is provided above the frame. The cooler 60 has a plurality of cooling tubes 61, a cooler cover 65, an inlet tube sheet 110, an outlet tube sheet 64, and guide plates 68a, 68b. The plurality of cooling pipes 61 are housed in a cooler cover 65. The cooler cover 65 has two plates on the side and a plate on the upper surface, and forms a box-like shape attached to the frame 40 together with the inlet tube plate 110 and the outlet tube plate 64. The plurality of cooling tubes 61 use a metal material such as stainless steel, copper, or aluminum. The inlet tube sheet 110 and the outlet tube sheet 64 are made of metal such as steel.

  The plurality of cooling pipes 61 are arranged in parallel with each other and extend in the axial direction. Both ends of each cooling pipe 61 are open. Further, both ends of each cooling pipe 61 pass through the inlet tube sheet 110 and the outlet tube sheet 64, and are fixed and supported by the inlet tube sheet 110 and the outlet tube sheet 64. The fixing portions of the cooling pipes 61 in the inlet tube sheet 110 and the outlet tube sheet 64 are hermetically sealed so as not to leak air.

  The height positions of the upper ends of the guide plates 68a and 68b are lower than the height positions of the inlet tube plate 110 and the outlet tube plate 64, and the lower ends thereof are the same height positions as the lower ends of the inlet tube plate 110 and the outlet tube plate 64. And are spaced apart from each other in parallel with the inlet tubesheet 110 and the outlet tubesheet 64. The upper communication space 65a at the top of the space in the cooler cover 65 is a region where the cooling pipe 61 does not exist. The portion of the space inside the cooler cover 65 other than the upper communication space 65a is divided into three sections in the axial direction by the guide plates 68a and 68b. A central portion in the axial direction, that is, a space between the guide plate 68a and the guide plate 68b communicates with the cooler inlet opening 66. Further, a portion sandwiched between the inlet tube plate 110 and the guide plate 68a and a portion sandwiched between the outlet tube plate 64 and the guide plate 68b are respectively provided with a cooler outlet opening 67a and a cooler formed in the upper part of the frame 40. It communicates with the outlet opening 67b.

  The frame 40, the non-connection side bearing bracket 45a, the connection side bearing bracket 45b, the cooler cover 65, the inlet tube plate 110, and the outlet tube plate 64 together form a closed space 70. In the cooler 60, the cooling pipe 61 is also an element forming the closed space 70, and the outside of the cooling pipe 61 is the closed space 70.

  The space on the frame 40 side and the space on the cooler cover 65 side communicate with each other through a cooler inlet opening 66 and cooler outlet openings 67a and 67b formed in the frame 40. The cooler inlet opening 66 is provided at the center in the axial direction, and the cooler outlet openings 67a and 67b are provided on both sides in the axial direction with the cooler outlet openings 67a and 67b interposed therebetween and above the inner fans 51a and 51b, respectively.

  The closed space 70 is filled with a cooling gas such as air. The cooling gas is driven by the inner fan 51 a and the inner fan 51 b and circulates in the closed space 70. Specifically, the inner fan 51a pumps the cooling gas from the anti-connection side bearing 30a side to the rotor core 12 side. Further, the inner fan 51b pumps the cooling gas from the connection-side bearing 30b side to the rotor core 12 side.

  The cooling gas pumped toward the rotor core 12 by the internal fans 51a and 51b from the anti-connection side and the connection side respectively flows into the rotor core 12 and the gap 18, and the rotor core 12 and the stator core 21 are fixed. After passing through the child windings 22 and the like while being cooled, they flow into the space outside the cooling pipe 61 of the cooler 60 via the cooler inlet opening 66.

  The cooling gas flowing into the cooler 60 via the cooler inlet opening 66 rises outside the cooling pipe 61 while being cooled by the outside air inside the cooling pipe 61 between the guide plates 68a and 68b. After that, it flows into the upper communication space 65a. The cooling gas that has flowed into the upper communication space 65a is diverted to both sides in the axial direction, that is, to the opposite connection side and the connection side.

  The cooling gas diverted from the upper communication space 65a to the anti-connection side, after turning downward, descends outside the cooling pipe 61 while being cooled by the cooling pipe 61, and passes through the cooler outlet opening 67a to the frame 40. Flows into. The cooling gas flowing into the frame 40 flows into the inner fan 51a, and is sent to the rotor core 12 and the stator 20 by the inner fan 51a. In this way, the cooling gas circulates in the circulation path on the opposite side.

  Further, the cooling gas diverted from the upper communication space 65a to the connection side turns downward, then descends outside the cooling pipe 61 while being cooled by the cooling pipe 61, and passes through the cooler outlet opening 67b to the frame. It flows into 40. The cooling gas that has flowed into the frame 40 flows into the inner fan 51b, and is pressure-fed to the rotor core 12 and the stator 20 by the inner fan 51b. As described above, the cooling gas circulates through the circulation channel on the connection side.

  As described above, the cooling gas circulates in the closed space 70 while being divided into two flow paths, the connection side circulation flow path and the anti-connection side circulation flow path.

  On the other hand, the outside air flows into the outside fan cover 56 from the outside air inlet 56a formed in the outside fan cover 56 by the outside fan 55, flows along the fan guide 56b, and is sucked into the outside fan 55. The outside air sucked into the outer fan 55 flows out in the radial direction of the outer fan 55, flows along the fan guide 56b and the inlet guide 56c, and is pressure-fed from the inlet tube plate 110 side into each of the plurality of cooling pipes 61. You. The outside air passing through the inside of each of the plurality of cooling tubes 61 rises in temperature while cooling the cooling gas flowing outside the cooling tubes 61, and then enters the exhaust cover 69 from the cooling tubes 61 on the outlet tube sheet 64 side. It flows out and is further discharged outside from below the exhaust cover 69.

  FIG. 2 is a partial longitudinal sectional view showing the configuration near the inlet of the cooling pipe. That is, details of a connection portion between the inlet tube sheet 110 and the cooling pipe 61 are shown. The arrows in the figure indicate the flow direction of the outside air. The same applies hereinafter.

  The inlet tube sheet 110 has a single flat plate portion 111 and a plurality of cylindrical support tube portions 112 projecting toward the cooling pipe 61 in a direction perpendicular to the flat plate portion 111. The plurality of support pipe portions 112 are formed at connection portions between the inlet tube sheet 110 and the cooling pipes 61, respectively. The support tube portion 112 has an outer diameter substantially equal to the inner diameter of the cooling pipe 61 and has an outer diameter slightly smaller than the inner diameter of the cooling pipe 61 so that the cooling pipe 61 can be inserted. The support pipe 112 extends to a predetermined position upstream of the outlet of the cooling pipe 61. That is, it has a length necessary to protect the inner surface of the inlet of the cooling pipe 61. In the assembled state of the cooler, the support tube portion 112 is inserted into the cooling tube 61.

  Here, the cooling pipe protection structure 100 for protecting the inner surface near the inlet of the cooling pipe 61 has a protection part 101a and a holding part 102a. Specifically, the support pipe portion 112 that covers the inner surface near the inlet of the cooling pipe 61 and protects the inner surface of the cooling pipe 61 corresponds to the protection portion 101a. Further, the flat plate portion 111 corresponds to the holding portion 102a. That is, since the protection portion 101a is connected to the flat plate portion 111 and is restrained by the holding portion 102a, the protection portion 101a is held without moving in the cooling pipe 61.

  In the portion where the support tube 112 is provided, the inlet tube plate 110 is formed with a through hole 112d having an inner diameter di equal to or substantially equal to the inner diameter of the support tube 112.

  On the inlet side of the through hole 112d, that is, on the side where the outer fan 55 is provided, a conical entrance taper portion 111a is formed. The inlet tapered portion 111a is formed in such a direction that the upstream side expands in the axial direction of the cooling pipe 61 and approaches the macro inner diameter di of the through hole 112d toward the downstream side.

  A conical exit taper portion 112a is formed on the exit side of the through hole 112d. The outlet tapered portion 112a is formed so as to expand in the axial direction of the cooling pipe 61 from the macro inner diameter di of the through hole 112d toward the downstream side.

  Further, a conical outer tapered portion 112b is formed radially outward of the downstream end of the support tube 112 such that the outer diameter decreases toward the end.

  The shapes of the tapered portions such as the inlet tapered portion 111a, the outlet tapered portion 112a, and the outer tapered portion 112b are not limited to the conical surface shape. The cross section may have a rounded shape or a streamlined shape in which the inclination changes continuously with the adjacent portion, and is preferable in reducing the pressure loss. The same applies to the following embodiments and the like.

  FIG. 3 is a partial vertical cross-sectional view showing a method of forming a support tube portion in an inlet tube sheet. FIG. 3 shows a state before processing for forming the entrance tapered portion 111a is performed.

  The order in which the inlet tapered portion 111a is formed after the formation of the support tube portion 112 is not limited. That is, the support tube 112 shown in FIG. 2 may be formed after the entrance tapered portion 111a is formed.

  The inlet tube sheet 110 is formed by attaching a support tube member 115 to a flat plate 114. The support pipe member 115 has a circular tubular shape, and has an outlet tapered portion 112a and an outer tapered portion 112b formed at a first end. In the flat plate 114, a through hole 114 a is formed at a position where the support tube portion 112 is provided in a direction perpendicular to a plane where the flat plate 114 expands. The inner diameter of the through-hole 114a is substantially equal to the outer diameter of the support pipe member 115, and is a dimension that allows the support pipe member 115 to be inserted into the through-hole 114a. The support tube member 115 is not limited to a circular tube. Even when the cooling pipe 61 is not a circular pipe, it may not be a circular pipe as long as it has a shape corresponding to the cross-sectional shape of the cooling pipe 61.

  The support pipe member 115 is inserted into the flat plate 114, and the second end opposite to the first end is aligned with the surface of the flat plate 114 at the same position, and is joined to the flat plate 114 by the welded portion 114b. . In addition, the groove | channel for welding which forms the welding part 114b is formed in the member 115 for support pipes, and the flat plate 114. FIG.

  FIG. 4 is a partial longitudinal sectional view showing a modified example of a method of forming a support tube portion in an inlet tube sheet. In this modification, the through hole 114a formed in the flat plate 114 is formed such that the inner diameter thereof is substantially equal to the inner diameter of the support pipe member 115. An outlet taper 112a and an outer taper 112b are similarly formed at the first end of the support pipe member 115.

  The support pipe member 115 is positioned so that its inner surface coincides with a through hole 114 a formed in the flat plate 114. The support pipe member 115 is welded to the flat plate 114 at the second end face by welding to form a welded portion 115a. The support pipe member 115 has a groove for welding to form the welded portion 115a.

  According to the combination of the cooling pipe 61 and the inlet tube sheet 110 according to the first embodiment configured as described above, the inner surface near the inlet of the cooling pipe 61 is protected by the inlet pipe sheet 110 and is directly connected to the outside air. It does not contact.

  Further, since the inlet taper portion 111a and the outlet taper portion 112a are formed, pressure loss due to contraction and expansion of the outside air is reduced. Further, since the outer tapered portion 112b is formed, the work of connecting the support pipe portion 112 and the cooling pipe 61 is facilitated, and the protection section 101a for protecting the inner surface near the inlet of the cooling pipe 61 is formed. This can reduce the effects of increased pressure loss or reduced workability.

  As described above, according to the present embodiment, it is possible to suppress corrosion of the cooling pipe that allows the outside air to pass, without depending on a complicated structure.

[Second embodiment]
FIG. 5 is a partial vertical cross-sectional view showing a configuration near an inlet of a cooling pipe of a fully-closed external fan-type rotary electric machine according to the second embodiment.

  The second embodiment is a modification of the first embodiment. The inlet tube sheet 120 in the second embodiment has the same shape as the inlet tube sheet 110 in the first embodiment, but differs from the first embodiment in that the material is nonmetal. The other points are the same as in the first embodiment.

  The inlet tube sheet 120 is made of chemically stable ceramics such as silicon carbide or resin such as carbon fiber reinforced plastic. As a method of forming the shape of the inlet tube sheet 120, a flat plate made of silicon carbide or resin and a member for a support tube may be combined in the same manner as in the first embodiment.

  Alternatively, the flat plate portion 121 and the support tube portion 122 may be simultaneously formed by injecting a silicon carbide powder into a mold and sintering, or by injecting a resin material into the mold and molding. In this case, the inlet taper 121a, the outlet taper 122a, and the outer taper 122b may be formed by a mold. Alternatively, if it is easy to form after integral molding, processing after integral molding may be used.

  Here, the support pipe 122 covers the inner surface near the inlet of the cooling pipe 61, and the support pipe 122 corresponds to the protection unit 101b. Further, the flat plate portion 121 corresponds to the holding portion 102b. Since the protection part 101b is connected to the flat plate part 121, it is held without moving in the cooling pipe 61.

  As described above, in the second embodiment, the vicinity of the outside air suction portion is covered with the chemically stable member, so that corrosion can be more reliably suppressed.

[Third Embodiment]
FIG. 6 is a partial longitudinal sectional view showing a configuration near an inlet of a cooling pipe of a fully-closed external fan-type rotary electric machine according to a third embodiment. The third embodiment is a modification of the second embodiment.

  The inlet tube sheet 63 is a material such as a normal steel material. The cooling pipe 61 is inserted into a through hole 63 a formed in the inlet tube plate 63, expanded at a fixing portion 63 b of the outer surface (outer fan side) of the inlet tube plate 63 with the inlet tube plate 63, It is connected to the plate 63. Note that the fixing portion 63b may be joined by welding.

  The protection member 130 is attached to the entrance of the cooling pipe 61 thus connected. The protection member 130 has a flat plate portion 131 and a cylindrical portion 132 having an axis in a direction perpendicular to a plane where the flat plate portion 131 expands. The flat plate portion 131 has a circular, rectangular, or polygonal outer diameter. The cylindrical portion 132 has a cylindrical shape, the outer diameter of which is substantially equal to the inner diameter of the cooling pipe 61, and a dimension that allows the cylindrical portion 132 to be inserted into the cooling pipe 61. In addition, even when the cooling pipe 61 is not a circular pipe, the cylindrical portion 132 may be formed in a shape and dimensions so as to be substantially in close contact with the inner surface of the cooling pipe 61.

  The protection member 130 has a through hole 132d that penetrates the protection member 130 in the axial direction of the cylindrical portion 132. On the outside air inlet side of the through hole 132d, an inlet tapered portion 131a is formed so as to expand toward the upstream side. An exit taper 132a is formed on the exit side of the through hole 132d so as to expand toward the downstream side. An outer tapered portion 132b is formed on the outer surface of the downstream end of the cylindrical portion 132 such that the diameter of the outer surface decreases toward the downstream side.

  Protective member 130 is made of silicon carbide or resin. In addition, although it may be made of metal, in the case of a material different from that of the cooling pipe 61, there is a problem of corrosion between different kinds of metals, but this can be dealt with by increasing the frequency of inspection.

  Since the direction in which the protection member 130 is inserted into the cooling pipe 61 is the flow direction of the outside air, there is no concern that the protection member 130 will come off due to wind pressure, and the protection member 130 does not need to be joined to the inlet tube sheet 63. That is, the protection member 130 may be detachable from the inlet side at the joint between the cooling pipe 61 and the inlet tube plate 63.

  FIG. 7 is a partial longitudinal sectional view showing a modification of the configuration near the inlet of the cooling pipe. FIG. 7 shows a state in which the protection member 130a is pulled out from a state in which the protection member 130a is in close contact with the inlet tube plate 63 for convenience of explanation.

  In the configuration shown in FIG. 6, the fixing portion 63 b between the cooling pipe 61 and the inlet tube plate 63 is, for example, cut off so as not to protrude from the surface of the inlet tube plate 63 on the outer fan 55 side. The protection member 130a is shown. On the other hand, if the protection member 130a is attached as it is to the fixing portion 63b which is not subjected to shaving or the like, the protection member 130a does not adhere to the surface of the inlet tube plate 63 and a gap is generated. Will come into direct contact with the outside air, causing partial corrosion.

  The protection member 130a according to the present modification is for effectively mounting even when the cooling pipe 61 and the inlet tube plate 63 are the fixed portions 63b that have not been cut off.

  Specifically, a groove 131b is formed on the back side of the flat plate portion 131 so as to cover a range facing the fixing portion 63b. The radially outer side of the groove 131b is a contact part 131c where no groove is formed, and at this part, the contact part 131c comes into close contact with the inlet tube plate 63.

  FIG. 8 is a partial vertical cross-sectional view showing a configuration in a case where the connection method between the cooling pipe and the inlet tube sheet is different. In this case, the cooling pipe 61 is welded to the fixed portion 63c of the downstream surface (the surface opposite to the outer fan) of the inlet tube plate 63 in which the through-hole 63a having the inner diameter equal to the inner diameter of the cooling tube 61 is formed. It is connected. In this case, the same protection member 130 as that of the embodiment can be used.

  In the present embodiment and the modification, the cylindrical portion 132 of the protection members 130 and 130a corresponds to the protection portion 101c of the cooling pipe protection structure 100 that protects the inner surface near the inlet of the cooling pipe 61. Further, the flat plate portion 131 corresponds to the holding portion 102c of the cooling pipe protection structure 100 that holds the protection portion 101c. That is, the protection members 130 and 130a correspond to the cooling pipe protection structure 100.

  As described above, in the present embodiment and its modifications, the inner surface near the inlet of the cooling pipe 61 is protected by the protection part 101c of the protection members 130 and 130a. By reducing the thickness of the cylindrical portion 132 of the protection member 130 as much as possible, an increase in pressure loss of the flow of the outside air due to the provision of the protection members 130 and 130a can be suppressed as much as possible.

  Furthermore, since the protection members 130 and 130a are removable, inspection can be performed easily, and the protection members 130 and 130a can be easily replaced, thereby improving the quality of maintenance and reducing the burden on maintenance work. be able to.

[Other Embodiments]
Although the embodiment of the present invention has been described above, the embodiment is presented as an example and is not intended to limit the scope of the invention. For example, in the embodiment, the case of the fully enclosed external fan type rotary electric machine has been described as an example, but the external fan may be a separately placed type. In addition, the protection of the cooling pipe is not limited to the cooler of the rotating electric machine, and it is necessary to prevent the corrosion of the inner surface of the cooling pipe, particularly at the inlet portion, due to dust and chemical substances in the cooling medium such as outside air. In such cases, the present invention can be applied to those cooling pipes.

  Furthermore, the embodiments can be implemented in other various forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. The embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... rotor, 11 ... rotor shaft, 11a ... connection part, 12 ... rotor core, 18 ... air gap, 20 ... stator, 21 ... stator core, 22 ... stator winding, 30a ... non-connection side bearing, 30b: Connection side bearing, 40: Frame, 45a: Anti-connection side bearing bracket, 45b: Connection side bearing bracket, 51a, 51b: Inner fan, 55: Outer fan, 56: Outer fan cover, 56a: Outside air inflow hole, 56b ... Fan guide, 56c ... Inlet guide, 60 ... Cooler, 61 ... Cooling pipe, 63 ... Inlet tube sheet, 63a ... Through hole, 63b, 63c ... Fixed part, 64 ... Outlet tube sheet, 65 ... Cooler cover, 65a ... upper communication space, 66 ... cooler inlet opening, 67a, 67b ... cooler outlet opening, 68a, 68b ... guide plate, 69 ... exhaust cover, 70 ... closed space, 100 ... cooling pipe protection structure, 101a, 101b, 1 1c: Protecting portion, 102a, 102b, 102c: holding portion, 110: inlet tube sheet, 111: flat plate portion, 111a: inlet taper portion, 112: support tube portion, 112a: outlet taper portion, 112b: outer taper portion, 112d ... through-hole, 114 ... flat plate, 114a ... through-hole, 114b ... welded part, 115 ... support pipe member, 115a ... welded part, 120 ... inlet tube sheet, 121 ... flat plate part, 121a ... inlet taper part, 122 ... support pipe Part, 122a ... outlet taper part, 122b ... outer taper part, 130, 130a ... protection member, 131 ... flat plate part, 131a ... inlet taper part, 131b ... groove part, 131c ... contact part, 132 ... cylinder part, 132a ... outlet taper Part, 132b: outer tapered part, 132d: through hole, 200: fully enclosed fan-shaped rotating electric machine

Claims (5)

A rotor shaft extending in the rotation axis direction and rotatably supported, and a rotor having a rotor core provided radially outside the rotor shaft;
A stator having a cylindrical stator core provided radially outside the rotor core, and a stator winding penetrating the stator core in the direction of the rotation axis;
A frame that is disposed radially outside of the stator and houses the rotor core and the stator;
A connection-side bearing and an anti-connection-side bearing that support the rotor shaft on both sides in the rotation axis direction with the rotor core interposed therebetween;
A connection-side bearing bracket and a non-connection-side bearing bracket that fixedly support each of the connection-side bearing and the anti-connection-side bearing and are connected to both ends of the frame in the rotation axis direction,
A plurality of cooling pipes extending in the rotation axis direction and arranged in parallel with each other, and an inlet tube plate supporting each of the ends of the plurality of cooling pipes and coupling with each of the plurality of cooling pipes at a coupling portion; An outlet tube sheet, a cooler cover that houses the cooling pipe, forms a closed space with the frame, the connection side bearing bracket, the non-connection side bearing bracket, the inlet tube sheet, and the outlet tube sheet; A cooler having a detachable cooling pipe protection structure provided on each of
An inner fan attached to the rotor shaft between the connection-side bearing and the anti-connection-side bearing to drive a cooling gas in the closed space;
An outer fan attached to an outside of the rotor shaft in the axial direction of the anti-connection side bearing to supply outside air to each of the plurality of cooling pipes;
A fully enclosed fan-shaped rotating electric machine comprising
The cooling pipe protection structure includes:
A cylindrical protection portion extending along the inner surface of each of the plurality of cooling pipes to a predetermined position on the upstream side of the outlet of the cooling pipe along the inner surface of each of the plurality of cooling pipes in an attached state of the cooling pipe protection structure ;
A holding portion having an opening formed at the center thereof which is coupled to the protection portion and restrains movement of the protection portion in the rotation axis direction, and an annular groove portion formed on a surface on the side where the protection portion is provided ;
A fully enclosed fan-shaped rotary electric machine characterized by having: The fully enclosed fan-shaped rotary electric machine according to claim 1, wherein the holding portion and the protection portion are made of ceramic or resin . An entrance taper portion that narrows in the flow direction is formed at an entrance edge of the central opening of the holding portion,
On the inner surface on the outlet side of the protection portion, an outlet taper portion expanding in the flow direction is formed,
The fully enclosed fan-shaped rotary electric machine according to claim 1 or 2 , wherein: The whole outer surface according to any one of claims 1 to 3, wherein an outer tapered portion whose diameter is reduced in a flow direction is formed on an outer surface on an outlet side of the protection portion. Closed fan electric rotating machine. A cooling pipe through which a cooling medium passes, and a cooling pipe having a cooling pipe having an inlet pipe sheet and an outlet pipe sheet respectively supporting an inlet end and an outlet end of the cooling medium; A cooling pipe protection structure for protecting an inner surface on an inlet side of the cooling pipe at a joint portion with an inlet pipe sheet,
A tubular protection portion extending in the axial direction of the cooling pipe along the inner surface of the cooling pipe in an attached state of the cooling pipe protection structure;
A holding portion having an opening formed at the center thereof, which is coupled to the protection portion and restraining the movement of the protection portion in the axial direction, and having an annular groove formed on a surface on which the protection portion is provided;
Cooling pipe protective structure, characterized in that it comprises a.

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