JP2001069712A - Motor frame, and motor and motor pump using that motor frame - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor and a motor pump which use a motor frame for cooling a mounted inverter with motor effectively and stably. SOLUTION: A first cylindrical part 1 in which a motor stator is housed, a second cylindrical part 2 which is arranged outside the first part 1 and forms a space for a fluid to be used to flow between itself and the first part 1, and a frequency converter fitting seat 3 formed in the peripheral part of the second part 2 are made of the same metal material into an integrated body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor frame, a motor using the motor frame, and a motor pump, and more particularly to a motor frame having a structure on the premise of mounting a frequency converter and using the motor frame. And a motor pump.

[0002]

2. Description of the Related Art Conventionally, there is known a pump assembly in which a frequency converter typified by an inverter is mounted on an electric motor pump so that heat generated by the frequency converter is removed by a pump handling liquid. For example, Japanese Patent Application No. 5-35099
No. 4 (Japanese Patent Application Laid-Open No. 7-189996) discloses a configuration in which an inverter is mounted on the outer surface of a cylindrical pump casing of a full-circulation pump. JP-A-7-189
In the pump assembly disclosed in Japanese Patent No. 996, the inverter is mounted on the outer surface of the pump casing of the all-circumferential flow type pump, so that a heat sink for cooling the inverter is not required, and the inverter can be downsized. The size of the motor is reduced by increasing the frequency of the electric power supplied to the motor, and the size of the pump is reduced by increasing the number of revolutions of the pump.

However, in the pump assembly disclosed in Japanese Patent Application Laid-Open No. 7-189996, the pump casing has a cylindrical shape, and the contact surface with the lower case made of sheet metal for accommodating the inverter has a curved surface. For this reason, there is a problem that the curvatures of the contact surfaces of the pump casing and the lower case do not coincide with each other and a gap is formed, and the cooling condition of the inverter is hardly stabilized. In addition, since the contact portion between the inverter and the lower case also has a curved surface, the heat transfer in this portion was likely to vary.

In order to improve the above-mentioned drawbacks, the applicant of the present application has previously filed Japanese Patent Application No. 9-524214, in which an aluminum alloy bracket is attached to the outer surface of a sheet metal pump casing, and an inverter (frequency conversion) Pump assembly in which the pump assembly is fixed. In this pump assembly, the contact surface between the bracket and the frequency converter assembly is flat, and there is little gap in this part,
Since the contact surface between the pump casing and the bracket has a curved surface, there is a problem that the cooling condition of the frequency converter is difficult to stabilize for the same reason as described above. Generally, in order to solve such a problem, a method of filling a gap by applying a filler such as liquid silicon to a contact surface is used, but this method is troublesome and is not preferable in terms of productivity. Was.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides a motor frame for effectively and stably water-cooling a mounted inverter, and a motor and a motor pump using the motor frame. The purpose is to do.

[0006]

In order to solve the above-mentioned problems, a motor frame according to the present invention is provided with a first cylindrical portion for accommodating a motor stator therein, and provided outside the first cylindrical portion. A second cylindrical portion that forms a space through which the handling fluid flows between the first cylindrical portion and a first cylindrical portion; and a frequency converter mounting seat provided on an outer peripheral portion of the second cylindrical portion. It is characterized by being integrally formed of the same metal material.

According to the present invention, since the frequency converter and the motor frame are in contact with each other, for example, at a flat seat, a gap is hardly formed between the two, and the cooling of the frequency converter is improved and the cooling conditions are stable. I do. Further, since the above-mentioned parts such as the aluminum alloy bracket are not interposed between the frequency converter and the motor frame, the frequency converter can be cooled very effectively. As a result, in some cases, it is not necessary to apply a filler such as liquid silicon to the contact surface, and the productivity can be improved.

According to one aspect of the present invention, a bolt and a bolt seat for fastening a bolt for securing coaxiality with a mounting component are provided at both axial ends of the cylindrical portion. As a result, it is possible to easily assemble the nozzle casing, which will be described later, and the liner ring fixed to the nozzle casing, and the coaxiality of the rotating body represented by the impeller easily.

According to one aspect of the present invention, a seat for mounting the frequency converter is disposed at a position between the bolt seats of the motor frame when viewed from the axial end. As a result, the frequency converter and the bolt for mounting the nozzle casing do not interfere with each other, and the area of the seat for mounting the frequency converter can be relatively increased, so that the frequency converter can be effectively cooled.

According to one aspect of the present invention, the length of the axial rib connecting the first tubular portion and the second tubular portion is at least half the length of the motor frame. As a result, the heat generated by the frequency converter is
The heat is effectively dissipated not only from the inner surface of the cylindrical portion but also from the rib surface.

[0011] Further, the handled liquid sucked from the suction side nozzle casing passes through the impeller and the guide device and is guided to the flow path of the motor frame. It contains flow components, which can lead to reduced pump efficiency and noise. This problem can be solved at the same time by extending the entire length of the rib connecting the first tubular portion and the second tubular portion of the motor frame.

Further, according to one aspect of the present invention, the axial end of the motor frame and the mating attachment component attached to the axial end are in direct contact. As a result, the heat generated by the frequency converter is effectively radiated not only from the inner surface of the second cylindrical portion of the motor frame but also from, for example, the inner surface of the nozzle casing.

A motor according to the present invention includes a motor frame, a motor stator housed in a first cylindrical portion of the motor frame, a motor frame side plate for closing an open end of the motor frame, and a motor stator. And a motor rotor rotatably supported by bearings installed on the motor frame and housed inside the motor frame. A motor pump according to the present invention includes the motor, an impeller fixed to a main shaft of the motor rotor, and a nozzle casing attached to an axial end of the motor frame and accommodating the impeller. It is assumed that.

[0014]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIGS. FIG. 1 is a longitudinal sectional view showing an all-periodic flow type inline pump which is an example of a motor pump according to the present invention. 2 is a sectional view taken along the line II-II in FIG. 1, and FIG. 3 is a view taken in the direction of the arrow III in FIG.

The all circumferential flow type motor pump shown in the present embodiment has a first cylindrical portion 1 which houses a motor stator therein,
The second cylindrical portion 2 which is provided outside the first cylindrical portion 1 and forms a space 50 between the first cylindrical portion 1 and where the handling fluid flows.
And a motor frame 4 in which a flat seat 3 for mounting a frequency converter provided on an outer peripheral portion of the second tubular portion 2 is integrally formed of a stainless cast steel material. The motor frame 4 is formed by, for example, a lost wax casting method. A motor stator 7 is shrink-fitted inside the first tubular portion 1, and a motor frame side plate 5 is hermetically welded to an axially open end of the first tubular portion 1. A stator can 6 made of a stainless steel thin plate is fitted on the inner peripheral portion of the motor stator 7, and the stator can 6 is hermetically welded to the motor frame 4 and the motor frame side plate 5.

As shown in FIG. 2, a flat seat 3 having a flat upper surface is provided on an outer peripheral portion of the second cylindrical portion 2 of the motor frame 4, and a frequency converter 8 is accommodated in the flat seat 3. The lower case 9 and the upper case 10 are attached. Due to the presence of the flat seat 3, the frequency converter 8 and the motor frame 4 are in flat contact with each other, so that it is difficult to form a gap between the two, and the cooling of the frequency converter 8 is improved and the cooling conditions are stabilized. As shown in FIG. 1, the output of the frequency converter 8 is supplied to the motor stator 7 through a lead wire 11 from a lead wire hole 3a provided in the flat seat 3. In addition,
An O-ring 12 is provided around the lead wire hole 3a to ensure airtightness between the inside of the case including the upper and lower cases 9, 10 and the inside of the motor frame 4 and the outside.

A motor rotor 13 is rotatably housed inside the motor stator 7. The motor rotor 13 is shrink-fitted and fixed to the main shaft 14, and the rotor can 15 is sealed and welded to the rotor side plates 16, 16 and the main shaft 14 to protect the motor rotor 13 from corrosion due to the handling liquid. The rotor can 15 and the rotor side plates 16, 16
The material of the spindle 14 is stainless steel. The main shaft 14 is supported at both ends by bearings (described later) installed on the motor frame 4, and an impeller 18 is fixed to one end of the main shaft 14. As the impeller 18, a cast molded product made of stainless cast steel or a press molded / welded product made of thin stainless steel is appropriately selected. In FIG. 1, a cast molded product made of stainless cast steel is shown in the upper half, and a press-formed and welded product formed by press-forming and welding thin stainless steel is shown in the lower half.

Next, the peripheral portion of the bearing on the side opposite to the thrust load provided on the side opposite to the impeller 18 will be described. The bearing bracket 20 is provided with a radial bearing 21 and a fixed-side thrust bearing 22. The end surface of the radial bearing 21 is also provided with a function as a fixed-side thrust bearing that supports a rarely generated reverse thrust load. On both sides of the radial bearing 21 and the fixed-side thrust bearing 22,
A rotating-side forward thrust bearing 23 for supporting a forward thrust load and a rotating-side reverse thrust bearing 24 for supporting a reverse thrust load are provided. The two thrust bearings 23, 24 are shrink-fitted and fixed to the thrust disks 25, 26, respectively.
Numeral 6 is fixed by a double nut 28 provided at the end of the main shaft 14 with a sleeve 27 constituting a sliding portion interposed between the radial bearing.

The bearing bracket 20 is inserted into an anchor 5a provided on the motor frame side plate 5 via an O-ring 29 made of an elastic material. The bearing bracket 20 is in contact with the motor frame side plate 5 via a gasket 30 made of an elastic material. The thrust bearing 2
2, 23, 24, the radial bearing 21 and the sleeve 27 are made of silicon carbide (SiC), which is a kind of ceramic material, and the bearing bracket 20 and the thrust disks 25 and 26 are made of stainless steel.

Next, the peripheral portion of the thrust load side bearing provided on the impeller side will be described. A radial bearing 32 is provided on the bearing bracket 31, and is inserted into the heater 4 a of the motor frame 4 via an O-ring 33 made of an elastic material. The radial bearing 32 and a sleeve 34 forming a sliding portion are fixed by a nut 36 provided at an end of the main shaft 14 via a washer 35 and an impeller 18.

At both ends in the axial direction of the second cylindrical portion 2 of the motor frame 4, there are provided heaters 2a, 2a for securing coaxiality with mounting parts and bolt seats 2b, 2 for fastening bolts.
The nozzle casings 40 and 41 made of stainless steel are fixed via an O-ring 38. The suction side nozzle casing 40 and the discharge side nozzle casing 41 integrally form the nozzles 40n, 41n and the mounting flanges 40f, 41f, respectively. The suction side nozzle casing 40 and the discharge side nozzle casing 41 are integrally formed by a lost wax casting method using stainless cast steel. The suction side nozzle casing 40 and the discharge side nozzle casing 41 are made of the same part, and the productivity is improved by sharing parts. A liner ring 42 forming a sliding portion with the impeller 18 is fixed to the suction side nozzle casing 40.

The suction side nozzle casing 40 is provided with a resin guiding device 4 for guiding the fluid discharged from the impeller 18.
3 is sandwiched between the motor frame 4. A gasket 44 made of an elastic material such as rubber is provided between the guide device 43 and the suction-side nozzle casing 40 to prevent unnecessary stress from being applied to the guide device 43 due to a variation in dimensional accuracy. 43 prevents the treated liquid whose pressure has been recovered and increased in pressure from flowing back to the impeller side. As shown in FIG. 3, the nozzle casing 40 is provided with a rib 45 for effectively preventing a swirling flow in the circumferential direction and improving suction performance and the like. An air vent valve 46 is attached to the outer periphery of the nozzle casings 40 and 41, and a screw hole 47 for pressure measurement and a screw hole 48 for water drain are provided. These screw holes are closed by plugs 49 and 49. I have.

As shown in FIG. 2, the planar seat 3 for mounting the frequency converter is located between the bolt seat 2b for mounting the nozzle casing and the bolt seat 2b when the motor frame 4 is viewed from the axial end. Has been placed. This is the frequency converter 8
And bolts 54 and nuts 5 for mounting the nozzle casing
This is to prevent interference of the frequency converter 5 and contribute to cooling of the frequency converter 8 because the area of the planar seat 3 for mounting the frequency converter can be relatively increased. The motor frame 4 and the nozzle casings 40 and 41 are fastened by the bolts 54 and the nuts 55 described above.

The length of the axial rib 17 connecting the first tubular portion 1 and the second tubular portion 2 is at least half the length of the motor frame 4 or more. As a result,
The heat generated by the frequency converter 8 is effectively radiated not only from the inner surface of the second tubular portion 2 of the motor frame 4 but also from the rib surface. The handled liquid sucked from the suction side nozzle casing 40 passes through the impeller 18 and the guide device 43 and is guided to the flow path 50 of the motor frame 4.
The handling liquid discharged from 3 contains a slight circumferential flow component, which may lead to a decrease in pump efficiency or noise. Here, this problem is simultaneously solved by extending the entire length of the rib 17 connecting the first tubular portion 1 and the second tubular portion 2 of the motor frame 4. The handling liquid guided to the flow path 50 of the motor frame 4 effectively cools the outer peripheral portion of the motor stator 7 and the frequency converter 8. Further, a part of the handling liquid lubricates and cools the bearings 21, 22, 23, 24, 32 and the sleeves 27, 34, and simultaneously cools the inner peripheral portion of the motor stator 7 and the motor rotor 13.

The axial ends of the motor frame 4 and the nozzle casings 40 and 41 are configured to be in direct contact with each other. As a result, the heat generated by the frequency converter 8 is not only dissipated from the inner surface of the second tubular portion 2 of the motor frame 4 but also transmitted to the nozzle casings 40 and 41 from the above-mentioned contact surface and handled from the inner surface. Heat is effectively dissipated by the liquid.

The frequency converter 8 is fixed in close contact with the lower case 9 and effectively radiates generated heat to the handling liquid. Lower case 9 and upper case 10 are mated with rubber gasket 5
6, and is fixed by fastening means such as bolts. A power cable 57 is attached to the lower case 9 as a means for inputting power from a power supply. This cable 57 is an airtight processing cable that prevents air from flowing from each core wire. Therefore, since the inside of the case composed of the upper and lower cases 9 and 10 is completely shut off from the outside air, even if the pump is used for circulating cold water in a high-temperature and high-humidity environment, dew condensation may occur in the case. There is no need to worry about insulation deterioration.

The motor is a two-pole three-phase induction motor, and is operated at a high speed of about 9600 revolutions per minute by electric power of, for example, 160 Hz and 200 V supplied from a frequency converter. As a result, downsizing of the pump section including the impeller and downsizing of the motor by reducing torque are achieved. At this time, in order to mount the frequency converter on a pump assembly that has been reduced in size and surface area, it is necessary to reduce the size of the frequency converter itself by improving cooling conditions, and the present invention makes this possible. .

In the above-described embodiment, an example is described in which a flat seat is provided on the outer peripheral portion of the second cylindrical portion. However, even if the flat seat is not a flat upper surface, it is possible to mount the frequency converter. A seat may be provided.

[0029]

As described above, according to the present invention, it is possible to provide a motor frame for effectively and stably water-cooling the mounted inverter, and to use the motor frame. A small motor and a motor pump can be provided. Furthermore, since the cooling conditions are generally good, it is possible to provide an extremely compact motor pump that achieves both downsizing of the pump and motor due to high speed and downsizing of the inverter.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an all-periodic flow type inline pump which is an example of a motor pump according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a view taken in the direction of the arrow III in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st cylindrical part 2 2nd cylindrical part 2a, 4a, 5a Inro 2b Bolt seat 3 Planar seat 3a Lead wire hole 4 Motor frame 5 Motor frame side plate 6 Stator can 7 Motor stator 8 Frequency converter 9 Lower case 10 Upper case 11 Lead wire 12, 29, 33, 38 O-ring 13 Motor rotor 14 Main shaft 15 Rotor can 16 Rotor side plate 17, 45 Rib 18 Impeller 20, 31, Bearing bracket 21, 32 Radial bearing 22 Fixed-side thrust bearing 23 Rotation-side forward thrust bearing 24 Rotation-side reverse thrust bearing 25, 26 Thrust disk 27, 34 Sleeve 28 Double nut 30, 44, 56 Gasket 35 Washer 36, 55 Nut 40 Suction side nozzle casing 40f, 41f Mounting flange 40n, 41n Nozzle 41 Exit side nozzle casing 42 liner ring 43 and guide device 46 purge valve 47 for pressure measurement screw holes 48 drain screw hole 49 Plug 50 passage 54 volt 57 power cable

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Katsuji Iijima 11-1 Haneda Asahimachi, Ota-ku, Tokyo F-term in Ebara Corporation (reference) 5H605 AA01 BB05 BB17 CC01 CC08 DD09 DD13 DD32 DD37 EC01 EC20 GG06 GG16

Claims (9)

[Claims] 1. A space for handling fluid to flow is formed between a first cylindrical portion accommodating a motor stator therein and a first cylindrical portion provided outside the first cylindrical portion. A motor frame, wherein a second cylindrical portion and a frequency converter mounting seat provided on an outer peripheral portion of the second cylindrical portion are integrally formed of the same metal material. 2. The bolt according to claim 1, wherein the second cylindrical portion is provided at both ends in the axial direction thereof with a bolt seat and a bolt seat for fastening a bolt for securing coaxiality with the mounting part. Motor frame as described. 3. The motor frame according to claim 2, wherein a seat for mounting the frequency converter is disposed at a position between the bolt seats of the motor frame when viewed from an axial end. 4. The motor according to claim 1, wherein the length of the axial rib connecting the first tubular portion and the second tubular portion is at least half of the entire length of the motor frame.
The motor frame according to any one of the preceding claims. 5. The motor vehicle according to claim 1, wherein an axial end of the motor frame and a mating component attached to the axial end are in direct contact with each other. Motor frame. 6. A motor frame according to claim 1, a motor stator housed in a first cylindrical portion of the motor frame, and a motor frame for closing an open end of the motor frame. A motor comprising: a side plate; and a motor rotor housed inside the motor stator and rotatably supported by bearings installed on the motor frame. 7. A motor comprising: the motor according to claim 6; an impeller fixed to a main shaft of the motor rotor; and a nozzle casing attached to an axial end of the motor frame and accommodating the impeller. Characteristic motor pump. 8. The motor pump according to claim 7, wherein the nozzle casing includes a suction side nozzle casing and a discharge side nozzle casing. 9. The motor pump according to claim 8, wherein the suction side nozzle casing and the discharge side nozzle casing are the same parts.