JPS6160656B2 - - 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 integral 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. Note that the connector 7 has a built-in connector pin to which the ground side of the surge absorber 62 is 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. 10,1
1 is a resin molded bracket made of the same material as the resin molded frame 4, and 12 is a power supply cable, and a cable side connector 13 connected to the tip thereof is molded inside the upper pump side bracket 10. Terminal piece 13 to which start switch unit 14 and ground terminal 22 are connected
1 is provided.

14 is 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 an auxiliary coil 15 in parallel with the main coil 151.
2 (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. Note that an antifreeze solution such as propylene glycol is sealed inside the can 3. Reference numeral 22 denotes a ground terminal molded inside the bracket 10, which is connected to the terminal piece 131 of the cable side connector 13 via a lead wire 23, and the outer end surface of the ground terminal 22 is the same as the outer peripheral surface of the bracket. It is exposed face up.

As described above, in this invention, the stator is surrounded by a resin mold frame, and the brackets are attached to this mold frame, so that they are not welded to the ends of the inner and outer cylinders like the conventional can type. A collar 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 this invention, the grounding terminal of the surge absorber unit is exposed and embedded within the bracket so that its outer end surface is flush with the outer peripheral surface of the bracket, making it extremely easy to assemble the grounding terminal. At the same time, it is possible to prevent interface separation between the bracket and the grounding terminal, thereby preventing deterioration of water resistance, and since the grounding terminal does not protrude from the outer peripheral surface of the bracket, damage during handling can be prevented. It also has a grounding structure and the effect of making work simple and easy.

[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 bracket, 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 the stator core, 3 is the can, and 4 is the stator core.
is the resin mold frame, 5 is the coil end,
6 is a surge absorber unit, 10 and 11 are brackets, 12 is a power supply cable, 14 is a starting switch unit, 15 is a stator coil, and 22 is a ground terminal.

Claims (1)

[Claims] 1. A molded frame in which the outer periphery and sides of the stator core and the periphery of the coil ends are surrounded with resin;
A bracket molded with resin is removably attached to the end opening of this molded frame.
A surge absorber unit embedded in the mold frame near the axial end of the coil end, and a surge absorber unit electrically connected to the surge absorber unit and embedded in the bracket, the end surface of which is flush with the outer peripheral surface of the bracket. A molded motor with an exposed ground terminal.