JPH07107384B2 - Pump unit in oil - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a pump unit used in a hydraulic machine such as a hydraulic elevator, and in particular, it is immersed in an oil tank in a state where a hydraulic pump drive motor is connected to the pump. Regarding what to use.

[Problems to be Solved by the Invention]

A pump unit which is used by immersing a hydraulic pump conventionally used for generating hydraulic pressure in a hydraulic circuit and a drive motor connected to the pump in oil in an oil tank is a source of a large drive noise and a pump and a pump. Since it is in the oil, it has the advantage of low noise. As the motor, a commercially available fully-closed outer fan-shaped motor is usually used. This fully-closed outer fan-shaped motor is fixed in the circumferential direction of the central portion of the inner surface of the casing (4) in the direction of the rotating shaft (2) as shown in FIG. 3, for example. Have a child (7),
A rotor (24) integral with the rotary shaft (2) is provided inside the stator (7), and the rotary shaft (2) has shielded bearings (3) at both end surfaces that penetrate the casing (4).
It is mounted rotatably in the circumferential direction of the casing (4) via (3 '), and an outer fan (25) for cooling the main body is mounted on one end of the rotating shaft (2) on the non-driving side. It has a different structure. Note that (26) in the figure shows the mounting base.

When using this fully-closed outer fan motor in an oil submersible pump unit, the outer fan, which is a resistance to rotation because it is immersed in oil, is removed, and cooling is performed with oil so that the pump is installed on the drive side of the rotating shaft. Such a pump unit is generally used because the structure is simple and the assembling work is quick even when the pump and the motor are connected.

However, as long as these commercially available mass-produced motors are used, some amount of oil will always penetrate into the motor even if it is a fully closed type. The oil stored in the motor acts as a large resistance against the rotation of the rotor due to its viscosity, and this tendency is remarkable because the viscosity is large especially at low temperatures, that is, at the start of operation. There is a drawback that the input current to the device increases and power consumption increases.

On the other hand, there is also a method of specially manufacturing a motor in which the sealing of the motor casing and bearings is particularly enhanced in order to reduce the intrusion of oil as much as possible, but this has the drawback that the manufacturing cost of the motor increases significantly. Moreover, when the conventional motor is used as it is, oil must be drained frequently, which is very troublesome work.

[Means for Solving the Problems]

The present invention has been variously studied in view of this, and in order to prevent the rotor of the motor from receiving the viscous resistance of the oil in the conventional commercially available motor as described above, the internal pressure is set in the oil tank by the following method. A method to keep the oil pressure higher than that was considered.

That is, (1) a method in which air or N ₂ gas is enclosed in the motor at high pressure to prevent oil from entering from the outside, or (2) compressed air is constantly supplied into the motor by an air compressor to increase the internal pressure. There are methods, etc., but since the method (1) cannot completely seal the inside of the motor, oil will be allowed to enter sooner or later, and the method (2) requires a constant operation of the compressor, which increases operating costs. Since it is clear that there are weaknesses such as connection, it was further investigated and a highly practical submersible oil pump unit was developed by making a slight improvement using a commercially available motor.

That is, the present invention relates to a submersible pump unit in which a driving motor connected to a hydraulic pump is immersed and arranged in oil in an oil tank together with the pump, and a drain is bored on the lower surface of the motor. And the through hole provided on the bottom surface of the oil tank are connected by a drain discharge pipe to constantly discharge the drain to the outside of the oil tank. Further, an air hole is formed on the upper surface of the motor, and the air hole communicates the inside of the motor with the atmosphere. It is characterized in that an air pipe is installed.

[Work]

In this way, a drain hole is drilled on the lower surface of the motor in oil,
Since the drain hole and the through hole on the bottom surface of the oil tank are connected by a drain discharge pipe so that the drain inside the motor is constantly discharged to the outside of the oil tank, the oil, that is, the drain, that enters without difficulty from the various shield parts of the motor, It has the advantage of being easily discharged through the drain hole and the discharge pipe without being stored in the motor.

At this time, at the same time, an air hole and an air pipe are provided on the upper surface of the motor so that the inside of the motor communicates with the standby. Therefore, since the inside of the motor is always at atmospheric pressure, the infiltrated oil smoothly flows through the drain hole to the lower part of the motor and is discharged. It has features.

Furthermore, by constantly observing the amount of oil infiltrated into the motor flowing out from the drain discharge pipe, it is possible to know the degree of wear and damage to the shield and bearings that make up the motor, and the timing of parts replacement and the life of the motor itself. It has a feature that acts as an indicator for estimating.

When the motor's rotating shaft is placed sideways, the interior of the motor is divided into two chambers by a stator mounted in the circumferential direction at the center of the axial direction. Since they are distributed, at least one drain hole is provided on each lower surface, so that the drain flowing into each chamber can be efficiently discharged separately.

The present invention is also effective when the rotary shaft is arranged vertically, and at this time, at least one drain hole may be provided on the lower surface in the axial direction, and the positional relationship between the motor and the pump is lower. It may be on the side or the upper side.

In any case, the air hole may be provided at any one position on the upper surface of the motor.

〔Example〕

 Next, an embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the rotary shaft (2) of a general fully-enclosed fan motor (1) is cut at the position of the outer end face of the shield bearing (3 ′) on the non-driving side, and the rotary shaft (2) is cut from the outside of the casing (4). A disk cover (5) is attached to the shield bearing (3 ') via a shield packing, and an oil seal (6) is further attached to the outside of the shield bearing (3) on the drive side of the rotating shaft (2). The airtightness inside the motor (1) has been improved. Further, drain holes (8) are provided on both sides of the stator (7) of the casing (4), which is the lower surface when the motor is installed with the rotating shaft (2) of the motor (1) oriented horizontally and immersed in oil.
(8 ') was bored at two places, and further, an air hole (9) was bored at one place on the upper surface of the casing (4), that is, the surface having the mounting base (26). Rotating shaft (2) of such a motor (1)
The drive shaft (11) of the hydraulic pump (10) is connected to the drive side of the motor (1) and the hydraulic pump (10) are assembled at a position such that the discharge port (12) of the pump (10) faces upward. Then, an in-oil pump unit (13) was produced.

As shown in FIG. 2, the pump unit (13) is provided with a mounting base (26), which is an upper surface of the pump unit (13), and a mount (1) for the oil tank (14).
It was fixed to the support frame (16) attached to 5), the suction port (17) of the pump was slightly raised from the bottom (18) of the oil tank (14), and the rotation axis of the motor was set sideways.

Further, the bottom surface (18) of the oil tank (14) is provided with two through holes (19) (19) ', and the motor drain hole (8) is provided.
The drain discharge pipes (20) (20 ') connected to (8') are passed through the through holes (19) (19 '), respectively, and the oil tank (14)
Drain collection and discharge measurement pot that extends outside (21)
Led to (21 '). Further, an air pipe (22) is connected to the air hole (9) of the motor, and the pipe (22) is guided onto the upper lid (23) of the oil tank (14) so that the inside of the motor is always kept equal to the atmospheric pressure. .

Then, by putting hydraulic oil in the oil tank (14) and completely immersing the pump unit (13) in the oil for a long time, there was no increase in the input current at the start of operation and the drain was discharged regularly. It was done in small amounts.

〔The invention's effect〕

As described above, according to the present invention, the operating cost is low because the motor rotor can always rotate without being subjected to the viscous resistance of oil by only slightly processing using a commercially available mass-produced motor,
Further, by checking the amount of drain discharged from the drain discharge pipe, it is possible to estimate the life of the motor and the like, which is a significant industrial effect.

[Brief description of drawings]

FIG. 1 is a side view showing a side cross section of an essential part of one embodiment of the present invention,
2 (a) and (b) show a state in which the in-oil pump unit of the present invention is installed in an oil tank, and (a) is a front view,
(B) is a side view and FIG. 3 is a side sectional view showing a general fully-closed outer fan motor. 1 …… Fully enclosed fan motor 2 …… Rotary shaft 3,3 ′ …… Shield bearing 4 …… Casing 5 …… Disc cover 6 …… Oil seal 7 …… Stator 8,8 ′ …… Drain hole 9… … Air hole 10 …… Hydraulic pump 11 …… Drive shaft 12 …… Discharge port 13 …… Oil pump unit 14 …… Oil tank 15 …… Stand 16 …… Support frame 17 …… Suction port 18 …… Bottom surface 19, 19 '... Through hole 20, 20' ... Drain discharge pipe 21, 21 '…… Discharge amount measurement pot 22 …… Air pipe 23 …… Top lid 24 …… Rotor 25 …… Outer fan 26 …… Mounting base

Claims (1)

[Claims] 1. An oil-in-water pump unit in which a driving motor connected to a hydraulic pump is immersed and arranged in oil in an oil tank together with the pump to operate, and a drain hole is formed in the lower surface of the motor. The drain hole and the through hole provided on the bottom surface of the oil tank are connected by a drain discharge pipe to constantly discharge the drain out of the oil tank. Further, an air hole is formed on the upper surface of the motor, and the inside of the motor and the atmosphere are connected to the air hole. An in-oil pump unit, which is provided with an air pipe that communicates with each other.