JP2544874Y2 - Underwater motor bearing structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a bearing structure of a submersible motor having an oil bath type shaft sealing device at a load side lead-out portion of a motor shaft.

[Prior art and its problems] As shown in Fig. 2, a conventional underwater motor has a load-side bearing 9 'and a non-load-side bearing 9 "on both sides of a rotor 6'. The load-side lead-out portion 8 'and the non-load-side lead-out portion 8 "of the motor shaft 7' are connected to respective bearings 9'9".
It is supported on a supporting letter. And these bearings 9 ', 9 "
Are mounted at predetermined positions by mounting housings 3 'and 3 ", respectively.

However, the housing that holds the bearing requires precision machining such as centering, and especially when using rolling bearings such as ball bearings and roller bearings, the motor shaft also requires high-precision machining. The cost of the bearing itself is high, coupled with the fact that the bearing itself is expensive. Further, when a sliding bearing is used as a bearing, there is a problem in lubrication and cooling, and there is a disadvantage that it cannot withstand long-term use. Furthermore, in the case of a single-phase motor, electrical components 11 'such as a condenser and a centrifugal switch are required,
Since these electrical components 11 'are usually mounted above the non-load-side bearing 9 "in the head cover 12', having a bearing on the non-load side is a major obstacle to downsizing the underwater motor.

For the purpose of reducing the size of the underwater motor, two rolling bearings are arranged in a single bearing housing between the motor chamber and the oil chamber, as shown in, for example, Japanese Utility Model Application Laid-Open No. 63-117256. There is something that did. Although this structure makes it possible to reduce the size of the underwater motor, the use of two expensive rolling bearings and the need for high-precision machining of the motor shaft in two places increase the cost. There is no difference from the conventional ones. In addition, since the distance between the two bearings is extremely small, there is a drawback that the body to be fitted at the shaft end causes so-called miso-sliding motion due to shaft run-out during rotation.

[Purpose of the Invention] An object of the present invention is to provide a bearing structure which eliminates the necessity of a non-load-side bearing and a mounting housing thereof, which can reduce the size of a motor, hardly cause shaft runout, and can be manufactured at low cost. .

[Structure of the Invention] In the bearing structure of the underwater motor according to the present invention, the partition provided between the motor chamber and the oil chamber is not used as the mounting housing of the load-side first bearing, and the oil chamber and the driven body are connected to each other. The partition wall provided therebetween is a mounting housing for the load-side second bearing, and a rolling bearing is mounted on the mounting housing of the load-side first bearing so as to face the motor chamber. The needle housing is mounted facing the oil chamber, and only the load-side lead-out portion of the motor shaft is supported in a cantilever manner by these two bearings. The needle bearing is lubricated by the shaft sealing device lubricating oil contained in the oil chamber. And it was configured to be cooled.

Example An embodiment will be described below with reference to FIG.

Reference numeral 1 denotes a motor chamber, and 2 denotes an oil chamber provided separately from the motor chamber 1, and contains oil for lubricating a shaft sealing device therein. Reference numeral 3a denotes a mounting housing of the first bearing, and a partition provided between the motor chamber 1 and the oil chamber 2 is applied to the housing. Reference numeral 3b denotes a mounting housing for the second bearing, to which a partition provided between the oil chamber 2 and a driven body 4 to be described later is applied.

Reference numeral 5 denotes a stator mounted in the motor chamber 1, reference numeral 6 denotes a rotor fitted in the stator 5, reference numeral 7 denotes a motor shaft fitted to the rotor 6, and a load-side lead-out portion 8 thereof. The driven member 4 such as, for example, a pump impeller is fitted to a leading end portion of the driven member 4 in a cantilever manner by a rolling bearing 9a and a needle bearing 9b.

The rolling bearing 9a that does not require oil supply is mounted facing the motor chamber 1 in the mounting housing 3a of the load-side first bearing, and the needle bearing 9b that requires oil supply is the load-side second bearing. The oil chamber 2 is separated from the rolling bearing 9a in the bearing mounting housing 3b.
The oil chamber 2 is originally provided with a shaft sealing device.
It is provided for lubrication of 10a, 10b, and is not specially provided for lubrication of needle bearing 9b.

In the bearing structure of the present invention, as described above, only the load-side lead-out portion 8 of the motor shaft 7 is supported in a cantilever manner, and the motor shaft is not led to the non-load side. Therefore, the electrical components 11 such as a condenser and a centrifugal switch are mounted by using these conventionally provided spaces. Reference numeral 12 denotes a head cover mounted above the motor room 1.

[Effects of the Invention] According to the bearing structure of the present invention, only the load-side lead-out portion 8 of the motor shaft 7 is supported in a cantilever manner. Since the need for the non-load-side bearing 9 "and its mounting housing 3" is not required, the portion requiring high-precision machining is reduced, and the number of expensive rolling bearings used is reduced by half, so that low-cost production can be achieved. . In addition, electric components such as a condenser and a centrifugal switch are used by utilizing a space in which the conventionally provided anti-load side bearing 9 "and its mounting housing 3" are omitted.
Since 11 is installed, the motor can be downsized accordingly. Further, the needle bearing 9b supporting the load-side lead-out portion 8 of the motor shaft 7 is provided in the oil chamber 2
Although the oil inside is lubricated and cooled, it can withstand long-term use. However, this oil chamber 2 is not specially provided for the needle bearing 9b, but is originally a shaft sealing device 10
It is extremely rational because the lubrication of a and 10b is used. Further, the rolling bearing 9a which does not require oil supply is held in the motor chamber 1 by the mounting housing 3a also serving as the upper wall of the oil chamber 2, and the needle bearing 9b which requires oil supply is provided in the oil chamber 2. The motor shaft 7 is held in the oil chamber 2 by the mounting housing 3b also serving as a lower wall, and the motor shaft 7 is in a two-point support mode, and the needle bearing 9b itself has a long shape in the axial direction, so that shaft runout is less likely to occur. There are advantages.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a main part of a motor having a bearing structure of the present invention, and FIG. 2 is a longitudinal sectional side view of a principal part of a motor having a conventional bearing structure. 1 ... Motor chamber, 2 ... Oil chamber, 3a ... Load side first
Mounting housing for bearing, 3b Mounting housing for second bearing on load side, 4 ... Driven body, 7 ... Motor shaft, 8 ...
Load-side lead-out section, 9a ... rolling bearing, 9b ... needle bearing.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho 63-117256 (JP, U) Japanese Utility Model Sho 62-143815 (JP, U) Japanese Utility Model Sho 62-84354 (JP, U) Japanese Utility Model Sho 60- 11646 (JP, U) Fully open sho 56-9854 (JP, U) Really open sho 56-177552 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] A partition provided between a motor chamber (1) and an oil chamber (2) is formed as a mounting housing (3a) for a first load-side bearing, and an oil chamber (2) and a driven body (4) are provided. ) Is formed as a mounting housing (3b) for the load-side second bearing, and a mounting housing (3a) for the load-side first bearing.
Is equipped with a rolling bearing (9a) facing the motor chamber (1), and a mounting bearing (3b) of the second bearing on the load side is fitted with a needle bearing (9b) facing the oil chamber (2). ,
Only the load-side lead-out portion (8) of the motor shaft (7) is supported in a cantilever manner by these two bearings (9a, 9b), and the needle is sealed by a shaft sealing device lubricating oil contained in the oil chamber (2). A bearing structure for a submersible motor, characterized in that the bearing (9b) is lubricated and cooled.