CN86204715U

CN86204715U - Internal-cooling electric pump

Info

Publication number: CN86204715U
Application number: CN 86204715
Authority: CN
Inventors: 施国梁
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-10-22
Filing date: 1986-10-22
Publication date: 1987-10-03

Abstract

The utility model relates to an internal cooling electric pump, in particular to an internal cooling type miniature electric centrifugal pump. Heat pipes used for cooling axially aligned are arranged in the stator iron core and the rotor iron core of an electric motor or a rotor shaft. The stator or the rotor can be cooled by the way of affusion towards the heat pipes. Thereby, the internal temperature of the electric motor can be reduced, in particular to the temperature of a bearing and a sealing ring in order to improve the working condition of the electric motor. The plastic housing is adopted to reduce cost, ease weight, and add electric safety. The utility model is suitable for the situations of washing machine draining, civil bailing, irrigation, etc.

Description

Internal-cooling electric pump

The utility model is about motor-drive pump, the particularly model utility of miniature electric centrifugal pump.These pumps adopt heat pipes or dynamic heat-pipe with the heat of motor internal is discharged, and available nonmetallic material such as plastics replace metal to make the parts such as shell of motor and pump.

For make motor-drive pump work safer, generally all wish to adopt the full seal type motor, will cause that the motor internal temperature is too high but directly do like this.Therefore, general canned motor pump all adopts submersible type or additional cooling unit to cool off.But this can increase danger or the cost of equipment that the electric leakage accident takes place, and limits its using scope.On the other hand, this type of cooling is pair poor with the cooling action of motor-drive pump closely-related bearing in working life and seal ring.

The purpose of this utility model provides a series of by adopting heat pipe or dynamic heat-pipe that thereby the heat of motor internal is passed to the motor-drive pump that liquid cools off motor.

Its solution is: in the stator of motor and rotor heat pipe is set.The rotor heat pipe can (also can be installed heat pipe also) and by output shaft heat be drawn in rotor iron core in output shaft, this is good especially to the direct current generator effect.With steel or stainless steel (material of output shaft) is that water was a working medium after the heat pipe of tube wall can adopt organic working medium such as acetone or carry out surface passivation.Also the heat pipe of making can be packed in the output shaft.The asynchronous motor that power is big slightly or other need to the motor that stator dispels the heat heat pipe to be installed in stator iron core.Lower with the copper water heat pipe cost, insulation such as available insulating material such as mylar between heat pipe and stator iron core, this does not have influence substantially to heat transfer effect.Axially arrange in stator iron core with several heat pipes, the motor internal temperature is evenly distributed vertically to reach best cooling effect.For making heat pipe work, can adopt forced water cooling that stator and rotor are cooled off, do like this than having better cooling effect by the shell forced water cooling, often can make motor select for use power to increase one-level.When heat pipe is in horizontal operation and pump or pipeline perseverance when being in the motor top, a kind of method preferably is that the cold junction with heat pipe puts in pump or the water pipe and dispels the heat.Also available cooling tube diversion opposite heat tube cold junction from pump or pipeline forces cooling when environment allows.Can make the heat pipe reliable operation like this, the device layout compactness; The submersible pump that working method is certain then directly stretches out the stator heat pipe to enter in the water and gets final product.

What consider in fact extensive use is single-phase asynchronous motor and centrifugal pump, and normal its pump of permission that requires is in below the motor.For reducing cost, conveniently using, centrifugal heat pipe can be installed in output shaft.This centrifugal heat pipe (in the harshest operating mode, motor last pump under condition under) rely on centrifugal force that working medium is promoted along tube wall replenish so that the large size hot junction obtains working medium at work all the time.And may command working medium consumption makes in heat pipe bottom and forms exposed cold junction, and the cold junction outside contacts with liquid.This centrifugal heat pipe can guarantee motor-drive pump where position in office reliably working.

The motor-drive pump of various employing heat pipes, the inside temperature in the time of can reducing machine operation effectively.As 370 watts of motors, can reduce temperature rise 30 degree with four stator heat pipes, even shell still can reduce about temperature rise 15 degree with thermoinsulation material.Thereby the temperature that rotor of output shaft axle adopts the motor-drive pump of heat pipe can reduce bearing and seal ring greatly reduces the volatilization of lubricant oil, and motor is prolonged more than one times working life.Can replace metal to make parts such as pump case with nonmetallic material for the little motor-drive pump of power, particularly miniature centrifugal electric pump.At this moment can reduce cost 30%, save metal 60%, weight reduction 40%.In addition, adopt the stator insulation design, promptly stator and extraneous no electrical link can reduce the probability 90% that the electric leakage accident takes place.Plastics (as polypropylene) are made shell, and are enough to the submersible pump intensity of 370 watts of motors.Consider to wear out, operating life also can reach 8 years, (be 5 years the projected life of aluminum alloy casing submersible pump).In addition can be by adopting modified polypropene and adding glass fibre and adopt metalware further to increase pump case intensity.Industries such as the applicable chemical industry of the pump of plastic casing, food.

Accompanying drawing 1 has provided 8 tons/hour of flows, and the embodiment of the plastic casing miniature electric submersible pump that lift is about five meters partly cuts open figure.With the single-phase the two poles of the earth of 250W asynchronous motor.Its stator (1) is with four copper water heat pipes (2) that the imbibition core is arranged, and with the stator electrical isolation, stretch out the top, with epoxy (3) sealing.From spiral case (6), water is drawn and force cooling by cooling tube (4) with nozzle (5) opposite heat tube external part.In case water pump burns out motor when not having in the subduction water, cooling tube also can omit according to circumstances.The below of heat pipe among the figure (2) puts in spiral case (6), does not stretch out when submersible pump working method one regularly also can make the below; Polypropylene plastics such as shell (7), spiral case (6), filter screen (8).Outer casing underpart and top except that with make the iron bar that protects frame (9) and handle (10) form with screw form spout tight, also can directly weld extremely.With a centrifugal heat pipe (12), make with the stainless steel output shaft in the rotor (11), tube wall has several axial grooves, without the imbibition core.Heat pipe stretches in institute's pump liquid.Working medium distribution shape when tiltedly dot and dash line (13) expression centrifugal heat plumber does.(in electric efficiency 75%(capacitor operating), inner used heat is 62.5W, four stator heat pipes can be dealt with problems) power supply introduces by port (14).But the work of this pump arbitrary orientation also can not submergence work.The tight screw etc. that spouts among the figure has been omitted.During assembling, rotor upper bearing (15) is fixed on the stator (1) by plastic pallet (16), can adjust air gap by adjusting stator and rotor simultaneously like this, and makes stator (1) and extraneous electric insulation.Can only in stator or rotor, use heat pipe according to actual conditions.Also can replace centrifugal switch (17) with thermistor.Consider that on-the-spot voltage is usually crossed low and this pump is not easy to be noted by the people configurable low voltage and overvoltage protection, electric leakage protector and buzzer.

For the cylinder that internal diameter is certain with rotating speed, shaft axis is vertical, wherein liquid surface is shaped as parabola.By theory analysis as can be known: the Sheng liquid cylinder that earth surface per minute 2800 changes, the clean poor h on highest point that liquid reaches on the tube wall and parabolic summit and the pass of pipe radius R are:

h＝（293.2R） ²／2g

Following table is several occurrences of this function, and wherein h gets centimetre and to be that unit, R be a millimeter unit

R	2	3	4	5	6	7	8	9	10
										h	1.7	3.9	6.9	11.1	15.8	21.1	27.5	34.8	43.0

In view of the cryogenic liquide heat-transfer capability poor, therefore need to select the heat pipe internal diameter and control centrifugal heat pipe liquid amount, so that its when vertical work (pump motor last) down (cold junction) opening is enough big in the bottom both to have made the pipe negative camber, make working medium can arrive the hot junction effectively again, preferably keep 0.5 to 2 millimeter working medium thickness.The heat pipe inwall is suitably held a little grooves can make better effects if.

For avoiding making the difficulty of centrifugal heat pipe, can adopt a kind of dynamic heat-pipe.So-called dynamic heat-pipe is such pipe, (suppose its vertical placement, when other orientation, can lose efficacy) its upper end sealing, there is air the centre, there is the inside crimping of one deck the lower end, in order to playing the liquid that one deck (a section) parabolic surface distributes in the tube wall upper support, the crimping internal face overcomes external force to the suction of lower end mouth liquid and slightly it is made progress lifting so that appropriate amount of fluid enters the power of crimping by the small impeller of being made up of several blades or its distortion in order to produce one when pipe pivots.In port central authorities an evacuation is arranged, in order to when pipe rotates, gas or liquid are extracted out so that produce a negative pressure in the pipe.The evaporation of liquid level is passed to port liquid internally with heat and is pulled away thereby this negative pressure can promote to be heated in the heat pipe.Simultaneously, small impeller is constantly to the hot junction liquid make-up.This just is similar to the phenomenon that produces in the centrifugal heat pipe, because this phenomenon is relevant with the working medium of rotating speed and institute's pumping, so be called dynamic heat-pipe.Dynamic heat-pipe can conduct heat and reliable performance under certain occasion effectively from the top down, makes simply, is worth so have than important use.

Accompanying drawing 2 has provided one and has used dynamic heat-pipe that the motor-drive pump embodiment of motor internal cooling is partly cutd open figure.By illustrated orientation work.This is sealed plastic shell (a 7) centrifugal pump that is used for draining on the washing machine, only makes a dynamic heat-pipe in output shaft (18).The effect of centrifugal pump impeller can be ignored the influence of dynamic heat-pipe operating conditions, and its evacuation is with several tubule (19).(only drawing one among the figure).One end puts in motor internal, and an end radially outward bending is to obtain bigger centrifugal force.Impeller on the crimping (20) is very little, and is similar to impeller among Fig. 3 (21).Evacuation also can be made into a horn shape, sees in the accompanying drawing 3 shown in (25).Accompanying drawing 3 is structural representations of a horn shape evacuation elements.The manufacturing of this single type evacuation is simple, but vacuum capability is poorer slightly, the small impeller (21) be made up of several blades is set with the enhancing effect of finding time at the evacuation inwall for this reason.Impeller can be with protruding formula or recessed formula.Be protruding formula among Fig. 3, recessed formula is a rule groove.Accompanying drawing 4 is top views of micro plastic shell motor-drive pump shown in Figure 2.Electric capacity work drive motor, electric capacity place position shown in (22), and power supply is introduced by aperture (23).Fig. 5 is an interface (a 24) sectional drawing, is funnel form.It can be connected in the water inlet of Fig. 3 water pump, so that water pump has certain suction journey, this is convenient to set up drainage means on existing washing machine, and can make water pump of the present utility model be used for more conditions.

Claims

1, a kind of inner-cooled motor-drive pump is made up of motor and centrifugal pump, it is characterized in that being provided with the but heat pipe of usefulness of axial arranged cooling in the stator iron core of motor and rotor iron core or rotor shaft, by to the heat pipe water flowing stator or rotor being cooled off.

2, inner-cooled motor-drive pump according to claim 1, the cold junction that it is characterized in that described heat pipe puts in pump or the water pipe and cools off.

3, inner-cooled motor-drive pump according to claim 1 and 2, it is characterized in that the heat pipe that is provided with is the pipe of a upper end sealing in described rotor shaft, there is an inside crimping lower end, in order to play the liquid that one deck parabolic surface distributes in the tube wall upper support, the crimping internal face has by several lobulate impellers, in order to promote cooling water when this motor-drive pump is worked.

4, inner-cooled motor-drive pump according to claim 1 and 2, it is characterized in that the heat pipe that is provided with is the pipe of a upper end sealing in described rotor shaft, there is an inside crimping lower end, be provided with by several ends in these heat pipe lower end central authorities and stretch to the evacuation that pipe that this inside heat pipe the other end radially bends is formed, cause negative pressure in order to find time.

5, inner-cooled motor-drive pump according to claim 1 and 2, it is characterized in that the heat pipe that is provided with is the pipe of a upper end sealing in described rotor shaft, there is an inside crimping lower end, be provided with a tubaeform evacuation in these heat pipe lower end central authorities, this evacuation inwall draws cooling water by the impeller of being made up of several blades in order to take out.

6,, it is characterized in that its shell is plastics according to the described inner-cooled motor-drive pump of one of claim 1 to 5.

7,, it is characterized in that pump intake is connected to a funnel shaped interface according to the described inner-cooled motor-drive pump of one of claim 1 to 5.