JP6607766B2 - Liquid-sealed electric motor and method for manufacturing power cable with sleeve used therefor - Google Patents

Description

  The present invention relates to a liquid ring type electric motor having a main shaft that rotates by energization from a power cable, and a method of manufacturing a power cable with a sleeve used in such a liquid ring type electric motor.

  The liquid ring motor has a liquid such as water sealed therein. In addition, a power cable covered with rubber is connected to the coil inside the liquid ring motor through the bracket from the outside. Therefore, it is necessary to prevent liquid from leaking between the bracket and the power cable.

  FIG. 9 is a cross-sectional view around the bracket 91 and the power cable 92 in a conventional liquid ring motor. A through hole 91a is provided in the bracket 91, and a power cable 92 passes through the through hole 91a. A rubber packing 93 is provided between the bracket 91 and the power cable 92 to prevent liquid from leaking. More specifically, the packing 93 is sandwiched from above and below by a metal packing retainer 94, and the cable support fitting 95 is tightened with a bolt 96 to compress the packing 93. As a result, a pressing force is generated on the contact surface between the packing 93 and the power cable 92, thereby realizing a sealing function.

Japanese Utility Model Publication No. 61-65854 Japanese Utility Model Publication No. 59-176356

  Since the covering of the packing 93 and the power cable 92 are both made of rubber, the compression force generated on the contact surface between the packing 93 and the power cable 92 may decrease due to hardening or permanent deformation due to deterioration over time. . Since rubber shrinks at a low temperature, there is a risk that the liquid sealed inside the liquid ring motor will leak together with the deterioration over time.

  Further, the portion of the power cable 92 that has been in contact with the packing 93 and has been subjected to the compressive force is gradually deformed. Therefore, it is difficult to obtain the same pressing force when disassembling the liquid-sealed electric motor for maintenance or the like, removing the power cable 92 and reassembling.

  The present invention has been made in view of such problems, and an object of the present invention is to manufacture a liquid ring type electric motor capable of suppressing deterioration of a power cable and a power cable with a sleeve used therefor Is to provide a method.

  According to one aspect of the present invention, a liquid is sealed inside, a housing provided with a through hole, a main shaft provided inside the housing, provided inside the housing, A coil for rotating the main shaft, a power cable having a resin sheath for passing through the through hole and energizing the coil, and a position of the power cable at a position facing at least a part of the through hole A resin-made fixing member provided around, a metal sleeve provided around the fixing member and fixed integrally with the fixing member, and a packing provided around the sleeve A liquid ring motor is provided.

  According to such a configuration, the metal sleeve is provided around the resin power cable, and the packing is provided around the metal sleeve. For this reason, the packing does not directly contact the power cable, and the power cable can be prevented from being thinned and deteriorated. Further, since the fixing member is also made of resin like the power cable, the fixing member can be prevented from being peeled off from the power cable.

It is desirable that the end portion of the fixing member has a tapered shape that becomes narrower toward the inside of the casing.
According to such a configuration, since the pressure of the liquid with respect to the fixing member is directed to the power cable side, the fixing member is further difficult to peel from the power cable.

It is desirable that a seal member fitted on the sleeve is provided at a position different from the packing.
According to such a configuration, even when the compression force of the packing is lowered, it is possible to suppress the liquid from leaking by the seal member.

A packing holding member provided on the packing, and a cable support member provided on the packing holding member and supporting the power cable, and the packing holding member is provided on the packing holding member from above the packing. There is a gap through which air can pass on the member side, and the cable support member is preferably provided with a hole through which air can pass through the gap of the packing pressing member to the outside of the cable support member.
According to such a configuration, since there is a passage for air, workability when installing the cable support member is improved.

The power cable and the fixing member are preferably made of the same resin.
Thereby, the adhesiveness of a power cable and a fixing member can be improved.

According to another aspect of the present invention, there is provided a method for manufacturing a power cable with a sleeve used in a liquid ring motor, the step of winding a thermosetting resin around a power cable having a resin coating, and the heat A step of fitting the sleeve made of metal on the outside of the curable resin, a step of winding a further thermosetting resin around the power cable so as to wrap one end of the sleeve, a step of curing the thermosetting resin, A method of manufacturing a power cable with a sleeve is provided.
Thereby, when a power cable is used for a liquid ring motor, it can control that a power cable deteriorates.

  Since the packing does not directly contact the power cable, deterioration of the power cable can be suppressed.

1 is a schematic cross-sectional view of a liquid ring motor 100. FIG. The enlarged view of the anti-load side bracket 2 and the power cable 12 periphery. The figure which shows the lower surface of the cable support fixture. The figure which looked at packing presser plate 22 from the upper part. Process drawing which shows the manufacturing method of the power cable 12 with the sleeve 14 concerning this embodiment. The figure explaining each process. The figure explaining each process. The figure explaining each process. Sectional drawing around the bracket 91 and the power cable 92 in a conventional liquid ring motor.

  Embodiments according to the present invention will be specifically described below with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view of a liquid ring motor 100. The liquid ring type electric motor 100 includes a cylindrical frame 1 that forms a casing 100a, and anti-load side brackets 2 and load side brackets 3 provided on the upper and lower parts thereof, respectively. Liquid 4 such as water is enclosed. The liquid ring motor 100 can be placed in water.

  Further, the liquid ring motor 100 includes a stator core 6 around which a coil 5 is wound, a rotor core 7, and a main shaft 8. The stator core 6 is attached to the inner surface of the frame 1. The rotor core 7 is fixed to the periphery of the main shaft 8 inside the housing 100 a and is rotatably provided in the center of the stator core 6.

  One end (downward in the figure) of the main shaft 8 passes through a hole provided in the load side bracket 3 and is connected to a load (not shown) such as a pump. Between the hole provided in the load side bracket 3 and the main shaft 8, a mechanical seal box 9 in which a mechanical seal 9a is disposed and a seal housing 9 'in which an oil seal 9'a is disposed are sealed. .

  Above the main shaft 8, a liquid hose 10 is attached to the anti-load side bracket 2 and is connected to a ground tank (not shown) for the motor body. Further, at a position different from the liquid hose 10, the liquid hose 11 passes through the anti-load side bracket 2 and is connected to a ground tank (not shown) for the mechanical chamber. The liquid 4 inside can be discharged to the ground tank through these liquid hoses 10 and 11 and plays a role of absorbing thermal expansion of the liquid 4 inside.

  Instead of providing the liquid hoses 10 and 11, a contractible diaphragm may be provided to absorb the thermal expansion of the liquid 4.

  Further, the liquid ring type electric motor 100 includes a power cable 12 that is connected to the coil 5 through the through hole 2a of the anti-load side bracket 2 from the outside. The power cable 12 has a resin coating such as rubber, and is typically a chloroprene sheathed cabtyre cable. When the coil 5 is energized from the power cable 12, the rotor core 7 rotates with the main shaft 8.

  FIG. 2 is an enlarged view of the periphery of the anti-load side bracket 2 and the power cable 12. 2A is a cross-sectional view passing through the center of the power cable 12, and FIG. 2B is a view of the power cable 12 as viewed from the front. The liquid ring type electric motor 100 includes a packing 13, a sleeve 14, and a fixing member 15. The power cable 12 has a rubber coating 12a. One feature of the present embodiment is that the power cable 12 with the sleeve 14 is used as shown in the figure.

  An annular packing 13 is provided in the through hole 2 a of the non-load side bracket 2. In addition, although the two packings 13 are drawn in FIG. 2, there is no restriction | limiting in particular in the number. In the present embodiment, the packing 13 and the power cable 12 are not in direct contact. That is, a cylindrical sleeve 14 and a fixing member 15 for positioning the sleeve 14 are provided between the packing 13 and the power cable 12, and the packing 13 is in contact with the sleeve 14. The sleeve 14 is made of metal. The fixing member 15 is preferably made of a resin such as rubber, and more preferably is the same material as the rubber covering the power cable 12.

  The fixing member 15 includes a space portion filling portion 15 a that fills a space portion between the power cable 12 and the sleeve 14, and a sleeve receiving portion 15 b provided below the space portion filling portion 15 a. The inner surfaces of the space filling portion 15 a and the sleeve receiving portion 15 b are in contact with the power cable 12. The sleeve 14 is provided between the space filling portion 15 a of the fixing member 15 and the packing 13. In other words, the sleeve 14 is fitted and fixed to the power cable 12 via the fixing member 15.

  Here, the inner surface of the sleeve 14 is preferably mortar-shaped. Friction is large and difficult to insert a metal sleeve on the rubber surface. The inner surface of the sleeve 14 is formed in a mortar shape with the end boss portion having a large diameter, and the shape of the space filling portion 15a is formed in accordance with the shape of the inner surface of the sleeve 14, thereby improving workability and the close contact between the sleeve 14 and the space filling portion 15a. Improves.

  The bottom surface of the sleeve 14 protects the boundary surface between the inner surface of the sleeve 14 and the space filling portion 15a by the sleeve receiving portion 15b of the fixing member 15, and the lower side surface of the sleeve 14 is sandwiched by the sleeve receiving portion 15b. It is integrated with the member 15.

  In other words, the space portion filling portion 15a of the fixing member 15 is provided and fixed around the power cable 12 at a position facing the through hole 2a. The sleeve 14 is provided around the fixing member 15 and is fixed integrally with the sleeve receiving portion 15 b of the fixing member 15. The packing 13 is provided around the sleeve 14. Here, the power cable 12 is in contact with the fixing member 15, the fixing member 15 is in contact with the sleeve 14, and the sleeve 14 is in contact with the packing 13.

  Thus, the power cable 12 is protected by the metal sleeve 14 so that the power cable 12 does not directly contact the packing 13. Therefore, it is possible to suppress deterioration such as the power cable 12 becoming thin. And since the sleeve 14 and the packing 13 are contacting, it can suppress that the liquid 4 leaks between both.

  If the fixing member 15 is made of a material having a large hardness difference from the power cable 12 such as an epoxy resin, the fixing member 15 may be separated from the power cable 12 by the pressure from the liquid 4. However, the fixing member 15 is also made of rubber (more preferably, the same material) as the covering 12 a of the power cable 12, so that the difference in hardness between the two is reduced, and the covering 12 a of the power cable 12 and the fixing member 15 are made strong. Can be glued.

  Further, if the lower portion of the sleeve receiving portion 15b is flat (horizontal), the stress from the liquid 4 is concentrated on the flat surface, and the fixing member 15 may be peeled off from the power cable 12. Therefore, as shown in FIG. 2A, it is desirable that the lower end portion of the sleeve receiving portion 15b has a tapered shape inclined so as to become narrower toward the inside (downward) of the liquid ring type electric motor 100. Thereby, since the pressure from the liquid 4 is directed to the power cable 12 side, the power cable 12 and the fixing member 15 can be firmly bonded. The lower portion of the sleeve receiving portion 15b may be inclined from the corner, or may be inclined from the middle of the lower surface as shown in FIG.

  The structure around the anti-load side bracket 2 and the power cable 12 will be described in more detail. The liquid ring motor 100 includes, for example, a stainless steel packing box 16, rubber O-rings 17 to 19, bolts 20, a cable support 21 (cable support member), and a stainless steel packing presser plate 22, for example. (Packing pressing member), a plug 23 and a bolt 24 are further provided.

  A part of the bottom surface of the packing box 16 is in contact with the end surface of the lower boss portion of the sleeve 14, and also serves to prevent the power cable 12, the sleeve 14 and the fixing member 15 from coming out of the through hole 2a. Further, the outer side surface of the packing box 16 is in contact with the anti-load side bracket 2. The O-ring 17 is provided between the anti-load side bracket 2 and the corner in contact with the packing box 16 and suppresses the liquid 4 from leaking from between the two.

  The packing 13 is accommodated in such a packing box 16. By tightening the bolt 20 reaching the anti-load side bracket 2 into the packing box 16, the packing box 16 and the anti-load side bracket 2 are fixed, and as a result, the packing 13 is appropriately positioned.

  Furthermore, it can be said that the through-hole of the packing box 16 is fitted with the sleeve 14. Therefore, if the O-ring 19 is disposed on the inner surface of the through hole of the packing box 16, further improvement in sealing performance is expected.

  In addition, when arrange | positioning O-ring 19 as a sealing member, the packing 13 does not need to be. Even when the O-ring 19 is not provided, an O-ring may be used as a seal member instead of the packing 13.

  A cable support 21 that supports the power cable 12 is provided on the packing presser plate 22. By tightening the bolt 24 reaching the packing box 16 into the cable support bracket 21, the cable support bracket 21 and the packing box 16 are fixed.

  The sleeve 14 extends to a position higher than the packing 13 (outside of the liquid ring motor 100), and the upper part of the outer side surface is fitted with the cable support fitting 21. Therefore, the O-ring 18a is disposed as a seal member and fitted to the sleeve 14 at the fitting position with the sleeve 14 inside the cable support fitting 21. Further, the O-ring 18 b is fitted to the outside of the cable support fitting 21 at the fitting position of the packing box 16 and the cable support fitting 21. This prevents the liquid 4 from leaking even when the packing 13 is aged and the compression force is reduced.

  When the O-rings 18a and 18b are provided, it is desirable to secure an air passage for fastening the cable support fitting 21 with the bolts 24 or disassembling the cable. For this purpose, the cable support 21 is provided with an air vent hole 21a.

  FIG. 3 is a view showing the lower surface of the cable support fitting 21. A hole 21c communicating with the air vent hole 21a in FIG. 2 is formed on the lower surface of the cable support bracket 21 (FIG. 3A), or a recessed groove 21b passing through the hole 21c is formed in the circumferential direction ( FIG. 3B).

  FIG. 4 is a view of the packing presser plate 22 as viewed from above. The packing holding plate 22 may be annular, but it has a C shape (FIG. 4A), a shape divided into two (FIG. 4B), and a shape that forms a groove recessed in the radial direction (FIG. 4C). It is desirable that there is a gap 22a for passing air. Air can pass from the upper part of the packing 13 to the cable support fitting 21 side through the gap 22a. Although the thickness of the packing presser plate 22 is not particularly limited, the members shown in FIGS. 4A and 4B may be thin plates having a thickness of about 1 to 2 mm.

  The packing presser plate 22 is disposed below the groove 21b or the hole 21c in the cable support fitting 21 so that the gap 22a in the packing presser plate 22 is located. When the cable support 21 is provided with a circumferential groove 21 b (FIG. 3B), a part of the groove 21 b is always located above the gap 22 a in the packing pressing plate 22. On the other hand, when the cable support fitting 21 has only the hole 21c (FIG. 3 (a)), the packing pressing plate 22 may be accurately arranged so that the gap 22a in the packing pressing plate 22 is positioned below the hole 21c.

  By using such a packing presser plate 22 and the cable support fitting 21, an air passage can be secured. That is, air can go out to the outside of the cable support fitting 21 through the gap 22 a of the packing holding plate 22 and the air vent hole 21 a of the cable support fitting 21. After the cable support fitting 21 is tightened with the bolt 24, the plug 23 may be tightened into the air vent hole 21a.

  FIG. 5 is a process diagram illustrating a method of manufacturing the power cable 12 with the sleeve 14 according to the present embodiment, and FIGS. 6 to 8 are diagrams illustrating each process. First, the raw rubber 15a 'is wound around the position where the sleeve 14 of the power cable 12 is provided (step S1). This raw rubber 15 a ′ becomes the space filling portion 15 a of the fixing member 15. As a result, the state shown in FIG. 6 is obtained. In addition, raw rubber means the thermosetting rubber (thermosetting resin) before a heating.

  Subsequently, the sleeve 14 is fitted to the outside of the raw rubber 15a '(step S2). As a result, the state shown in FIG. 7 is obtained.

  Thereafter, the raw rubber 15b 'is further wound thicker than the raw rubber 15a' wound in step S1 so that a part of the lower end of the sleeve 14 is wrapped (step S3). At this time, it is desirable that the lower part is tapered. This raw rubber 15 b ′ becomes a sleeve receiving portion 15 b of the fixing member 15. As a result, the state shown in FIG. 8 is obtained.

  Then, the raw rubbers 15a 'and 15b' are vulcanized and cured by being put in a mold and heated (step S4). Thereby, the raw rubbers 15 a ′ and 15 b ′ become the fixing member 15. Thus, the power cable 12 with the sleeve 14 is formed. Thereafter, the power cable 12 in this state may be inserted into the through hole 2a of the anti-load side bracket 2.

  As described above, in this embodiment, the metal sleeve 14 is provided around the power cable 12 having the rubber coating 12 a so that the packing 13 does not directly contact the power cable 12. Therefore, deterioration of the power cable 12 can be suppressed. Further, since the fixing member 15 for fixing the sleeve 14 is made of rubber like the power cable 12, it is possible to prevent the fixing member 15 from peeling off.

  The embodiment described above is described for the purpose of enabling the person having ordinary knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above embodiment can be naturally made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Therefore, the present invention should not be limited to the described embodiments, but should be the widest scope according to the technical idea defined by the claims.

1 Frame 2 Anti-load side bracket 2a Through-hole 3 Load side bracket 4 Liquid 5 Coil 6 Stator core 7 Rotor core 8 Spindle 9 Mechanical seal box 9a Mechanical seal 9 'Seal housing 9'a Oil seal 10, 11 Liquid hose 12 Power cable 12a Cover 13 Packing 14 Sleeve 15 Fixing member 15a Space filling portion 15b Sleeve receiving portion 15a ', 15b' Raw rubber 16 Packing box 17-19 O-ring 20 Bolt 21 Cable support bracket 21a Air vent hole 21b Groove 21c Hole 22 Packing retainer plate 22a Gap 23 Plug 91 Bracket 91a Through hole 92 Power cable 93 Packing 94 Packing retainer 95 Cable support fitting 100 Liquid ring type electric motor 100a Case

Claims (6)

A housing in which liquid is sealed and a through hole is provided;
A main shaft provided inside the housing;
A coil provided inside the housing for rotating the main shaft;
A power cable having a resin coating for passing through the through hole and energizing the coil;
A resin-made fixing member provided around the power cable at a position facing at least a part of the through hole;
A metal sleeve provided around the fixing member and fixed integrally with the fixing member;
Packing provided around the sleeve;
A packing holding member provided on the packing;
A cable support member provided on the packing holding member and supporting the power cable ; and
The packing holding member has a gap through which air can pass from the upper part of the packing to the packing holding member side,
The cable support member is liquid-sealed type motor-hole may pass air to the outside of the cable support member through the gap of the gland member that is provided.   The liquid ring electric motor according to claim 1, wherein an end portion of the fixing member has a tapered shape that becomes narrower toward the inside of the housing.   The liquid ring electric motor according to claim 1, further comprising a seal member fitted to the sleeve at a position different from the packing.   The liquid ring motor according to claim 1, wherein the power cable and the fixing member are made of the same resin. A method for manufacturing a power cable with a sleeve used in a liquid ring motor,
Winding a thermosetting resin around a power cable having a resin coating;
Fitting the metal sleeve on the outside of the thermosetting resin;
Winding a further thermosetting resin around the power cable to wrap one end of the sleeve;
A method of manufacturing a power cable with a sleeve, comprising: curing the thermosetting resin by placing in a mold and heating . A method for manufacturing a power cable with a sleeve used in a liquid ring motor,
  A step of winding a thermosetting resin that becomes the same material as the coating by curing on a power cable having a resin coating;
  Fitting the metal sleeve on the outside of the thermosetting resin;
  Winding a further thermosetting resin around the power cable to wrap one end of the sleeve;
  A step of curing the thermosetting resin; and a method of manufacturing a power cable with a sleeve.