JPS6160657B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a molded motor with a built-in surge absorber, particularly one suitable for a submersible motor for wells.

Conventionally, underwater motors are known to have a structure called a canned type, that is, a structure in which stainless steel cylinders are fitted around the inner and outer peripheries of a stator core, and a thrust bearing lubricating liquid is sealed in the inner cylinder.

However, although the canned motor has excellent electrical insulation from the stator coil, it also requires a collar to close the ends of the inner and outer cylinders and to fix the bracket, which increases the number of parts. Moreover, it is necessary to perform machining on the collar in order to fit the two cylinders together with a spigot, and the number of assembly steps also increases accordingly, resulting in a disadvantage that the manufacturing cost becomes high.

The present invention provides a molded motor which eliminates such drawbacks, and will be explained below with reference to the drawings.

In FIGS. 1 and 2, 1 is a stator consisting of a stator core 2 and a stator coil 15 (FIG. 4), into which a stainless steel cylinder 3 is inserted.

4 is a resin mold frame made of polyester resin or vinyl ester resin surrounding the outer periphery and sides of the stator core 2 and the coil end 5 of the stator coil; 6 is a surge absorber unit; as shown in FIG. It is composed of a pair of surge absorber elements 61 and 62 (for example, a plurality of voltage-dependent resistance elements mainly made of zinc oxide are stacked and housed in a ceramic tube) and a resistance element 63.

Reference numeral 7 denotes a lead wire side connector, one half of which is molded on the upper end of the resin mold frame 4, to which the lead wire 8 and the surge absorber unit 6 are connected. Reference numeral 9 denotes a plurality of screws embedded in both ends of the resin mold frame 5 for tightening a bracket 10, which will be described later.

10 and 11 are resin mold brackets made of the same material as the resin mold frame 4;
2 is a power supply cable, and the cable side connector 13 connected to the tip is connected to the upper pump side bracket 10.
Molded inside.

Reference numeral 14 designates an electronic start switch unit molded in the pump side bracket 10, which closes when the motor stops, opens after reaching a predetermined speed, and connects the auxiliary coil 1 in parallel with the main coil 151.
52 (Figure 4).

16 and 17 are tightening bolts, 18 is a sleeve bearing, 19 is a thrust bearing, 20 is a rotor, and 21 is an internal pressure adjustment device. Reference numeral 22 denotes a ground terminal buried in the mold frame 4, which is connected to the surge absorber unit 6 via a lead wire 23, and the outer end surface of the ground terminal 22 is flush with the outer peripheral surface of the mold frame. That's how it's exposed.

Note that an antifreeze solution such as propylene glycol is sealed inside the can 3.

As described above, in this invention, the stator is surrounded by a resin molded frame, and the bracket is attached to this molded frame, so unlike the conventional can type, the stator is not welded to the ends of the inner and outer cylinders. A crucible is not required, which not only reduces the number of parts, but also eliminates the need for machining for spigot fitting, which has the effect of lowering manufacturing costs.

Furthermore, in the present invention, both the surge absorber unit and its ground terminal are buried in the mold frame, and the ground terminal is exposed so that its outer end surface is flush with the outer peripheral surface of the mold frame. This simplifies the assembly of the parts into the motor, prevents separation of the interface between the mold frame and the ground terminal, prevents deterioration of water resistance, and prevents the ground terminal from protruding from the outer peripheral surface of the mold frame. Therefore, it is possible to prevent damage during handling, and furthermore, the grounding structure and work can be easily performed.

[Brief explanation of the drawing]

The figure relates to one embodiment of the present invention.
2 is an enlarged sectional view of the main part, FIG. 3 is a side view of the mold frame, and FIG. 4 is an electric circuit diagram. Note that the same reference numerals in the figures indicate the same parts. In the figure, 1 is a stator, 2 is a stator core, and 3 is a stator.
is the can, 4 is the molded frame, 5 is the coil end, 6 is the surge absorber unit, 10, 1
1 is a bracket, 12 is a power supply cable, 14 is a starting switch unit, 15 is a stator coil, 22
is the ground terminal.

Claims (1)

[Claims] 1. Molding the outer periphery and sides of the stator core and the periphery of the coil ends with a resin molding member to form a molded frame, and at the same time molding a bracket detachably attached to the end opening of the molded frame with the resin molding member. A surge absorber unit is buried in the mold frame, and a ground terminal electrically connected to the surge absorber unit is buried in the mold frame so that the end surface is flush with the outer peripheral surface of the mold frame. The molded motor exposed in this way.