CN1256366A - Small pump device and electric thermos bottle - Google Patents

Abstract

A small pump device is provided with an introducing part for introducing liquid, a discharging part for discharging the liquid introduced from the introducing part, and a liquid passage for connecting the introducing part to the discharging part. In the device, two sets of pumping mechanisms each consisting of a screw pump having a lead screw within a straight part of the liquid passage and a centrifugal pump having an impeller are arranged on the same axis. The inside diameter in the straight part differs from place to place. The invention makes liquid be discharged efficiently, prevents cavitation, and makes the liquid flow backward surely and smoothly.

Description

Small pump device and electric hot water bottle

The present invention relates to small pump device device and the electric hot water bottle with liquid importing and discharge with premium on currency mechanism.

Past attempts proposed the various small pump devices that have in the water heating devices such as the electrodynamic type premium on currency mechanism that utilizes the motoring source, the electric hot water bottle of packing into.This small pump device adopts so-called centrifugal pump formula, that is, rotatablely move and utilize centrifugal action to attract liquid by the impeller high speed rotating is applied to liquid, discharges from the top water outlet of vacuum bottle device etc. again.In the occasion that this small pump device is used for electric hot water bottle, when the water that seethes with excitement in water bottle promoted, air pocket (cavitation) phenomenon took place in regular meeting.

So-called cavitation, be meant when temperature risen near the boiling point liquid and rise to around the impeller, because the negative pressure around the impeller makes the boiling point reduction of liquid etc. can make liquid gasification rapidly around impeller, be full of air, or the bubble that produces during liquid boiling expands rapidly around impeller, and gas such as air is full of in the chamber that impeller is set.When promoting the hot water of boiling, in case this cavitation takes place, make gas concentrate on the rotating center of impeller, impeller will dally, and can not promote hot water.

On the other hand, when pump-unit was used for electric hot water bottle, requirement can make the liquid in the pump-unit flow back in the water bottle, to mix with liquid in the water bottle.This is in order to prevent following situation, promptly for a long time need not the back in case make the liquid discharging operation, the liquid that cools off in the pump-unit in the water bottle outside can be discharged from water outlet, causes the 1st glass to be the water of cold water or tepor.

Considered with a kind of centrifugal pump and volute pump and solved this cavitation or " first glass is tepid water " that this pump-unit was the volute pump that setting has screw (1eadscrew) on centrifugal pump impeller coaxial with the formula pump-unit.If only use screw, because it also has problem aspect pump efficiency, so traditional approach is with centrifugal pump and uses as premium on currency mechanism.If with this and with the formula pump-unit as the premium apparatus of electric hot water bottle, have following effect:

The centrifugal force that 1. can utilize centrifugal pump is drain effectively.

2. with screw liquid is transported to the impeller of centrifugal pump, can prevents impeller idle running, so be difficult for the generation cavitation.

3. by making the screw reversing that liquid is flow backwards, the liquid that has cooled off in pump-unit can return in the warm water bottle.

Yet even adopt and use the formula pump-unit, above-mentioned 3 effects are still insufficient, also have the leeway of improveing.For example, the pump capacity of original volute pump self is lower than centrifugal pump, but when this pump capacity is extremely low, just can not realize effect 2. above-mentioned and 3..That is, liquid can not be transported to impeller when just changeing, and liquid is flow backwards.

Also have, if volute pump increases pitch by the angle of lead that increases screw, though then pump capacity rising (ability during reversing also rises), but in this occasion, when the hot water that seethes with excitement in the water bottle when water bottle is transported to screw, hot water easily with the screw collision, form bubble easily.Therefore, screw self can be surrounded by bubble, partly produces so-called cavitation in lead screw, so liquid can not be transported to impeller with screw, causes impeller idle running.

In addition, in case make the screw reversing, the rotating force of screw can make the liquid in the pump-unit flow backwards to water bottle one side, but also one rotation of the impeller of centrifugal pump at this moment.Therefore, centrifugal pump will make liquid move to exhaust end.As a result, although the power of volute pump will make the liquid in the pump-unit flow backwards to water bottle,, just can not successfully flow backwards because of the influence of the power that makes the liquid discharge that is subjected to centrifugal pump.

The object of the present invention is to provide a kind ofly with above-mentioned centrifugal pump and the volute pump small pump device as premium on currency mechanism and usefulness, it is drain more effectively, prevents cavitation reliably, and can liquid be flow backwards smoothly.The present invention also aims to provide a kind of pump-unit with compact spiral pump, it is provided with screw, even do not use centrifugal pump for the various shortcomings of avoiding centrifugal pump, also has enough pump capacities.The present invention also aims to provide a kind of electric hot water bottle that uses this small pump device.

To achieve these goals, the small pump device of technological scheme 1 is provided with the introduction part that imports liquid, make discharge portion that the liquid that imports from this introduction part discharges from the position of introduction part upside, introduction part is connected with discharge portion and at least a portion has the fluid passage of vertical tube part, coaxial setting is by the volute pump with screw and have 2 premium on currency mechanisms that the centrifugal pump of impeller constitutes in the vertical tube part of this fluid passage, be characterized in that the internal diameter of vertical tube part is at different parts and different.

Therefore, when liquid was flow backwards, the liquid fluid capacitance in the vertical tube part easily was broken into 2 layers by volute pump and centrifugal pump branch, and the liquid that is formed by centrifugal pump is not to mobilely can exerting an influence to the reverse flow of the liquid that formed by volute pump of discharging direction.

Technological scheme 2 is on the small pump device of scheme 1, the internal diameter of the part of the covering screw of vertical tube part is made the internal diameter of the part of the covering impeller that is different from vertical tube part, so when flowing backwards, the liquid stream that volute pump forms can separate more reliably with the liquid stream that centrifugal pump forms.

Technological scheme 3 is on the small pump device of scheme 1 or 2, and the internal diameter of the part of the covering screw of vertical tube part is greater than the internal diameter of the part of the covering impeller of vertical tube part, so when flowing backwards, impeller is just littler to the influence of the liquid stream that volute pump forms.

Technological scheme 4 is on the small pump device of scheme 1, the internal diameter of the part of the covering screw of vertical tube part made with the internal diameter of the part of the covering impeller of vertical tube part make same inner diameter, and in the part of the covering screw of vertical tube part with cover part between the part of impeller and form the bump that central direction to vertical tube part protrudes and the internal diameter of this part is dwindled.Therefore, during refluence, liquid flows by the bump disjunction, with volute pump liquid is flow backwards.

Technological scheme 5 is on the small pump device of scheme 1,2,3 or 4, installs in the end of vertical tube part and carries out the position retaining member that the position keeps to rotating the axial region that supports screw and impeller freely.Therefore, be convenient to assembling, and can prevent screw and impeller outer circumference end collision vertical tube part inwall and produce noise.

Technological scheme 6 is on the small pump device of scheme 5, and the position retaining member is made the cylinder element that embeds the vertical tube part inwall, and the many roots that protrude from inwall one side direction center one side of this cylinder element are set.Therefore, during refluence, rib will flow because of the liquid that the effect of volute pump is flow backwards from by disjunction the liquid stream of centrifugal pump and volute pump rotation, can prevent that like this ability of volute pump from reducing.

Technological scheme 7 is a kind of small pump devices, the fluid passage that is provided with the introduction part that imports liquid, makes discharge portion that the liquid that imports from this introduction part discharges from the position of introduction part upside, introduction part is connected with discharge portion, in the inner coaxial setting of this fluid passage by volute pump and have 2 premium on currency mechanisms that the centrifugal pump of impeller constitutes with screw, be characterized in that the external diameter of impeller is less than the external diameter of screw.

Therefore, aspect the pump capacity and the equilibrium relation between the centrifugal pump of screw, compare with traditional product, volute pump one side is bigger.As a result, the formed liquid of centrifugal pump can make liquid flow backwards to discharging the mobile less to the influence of flowing of backflow direction to the formed liquid of volute pump of direction more reliably during refluence.

Technological scheme 8 is on the small pump device of scheme 7, and the external diameter of impeller is made 20～80% of screw external diameter, so liquid is flow backwards when flowing backwards.

Technological scheme 9 is, at least a portion of aforementioned liquids passage has vertical tube part, and be provided with said spiral pump and aforementioned centrifugal pump at this vertical tube part, the internal diameter of the part of the aforementioned screw of covering of aforementioned vertical tube part is greater than the internal diameter of the part of the aforementioned impeller of covering of aforementioned vertical tube part.

Technological scheme 10 is a kind of small pump devices, the fluid passage that is provided with the introduction part that imports liquid, makes discharge portion that the liquid that imports from this introduction part discharges from the position of introduction part upside, introduction part is connected with discharge portion, in the premium on currency mechanism that the inner coaxial setting of this fluid passage is made of the volute pump with screw, be characterized in that screw constitutes with the single-screw (a silver lap I) of 5～15 ° of angle of lead.Therefore, both can guarantee the pump efficiency of volute pump, be difficult for producing cavitation again.

Technological scheme 11 is on the small pump device of scheme 9, and the angle of lead of screw is made more than 8 °, so can both prevent cavitation, can guarantee the more high pump efficiency rate of volute pump again.

Technological scheme 12 is a kind of small pump devices, the fluid passage that is provided with the introduction part that imports liquid, makes discharge portion that the liquid that imports from this introduction part discharges from the position of introduction part upside, introduction part is connected with discharge portion, in the premium on currency mechanism that the inner coaxial setting of this fluid passage is made of the volute pump with screw, be characterized in, the spire of screw is made more than the 25mm in axial length.In case prolong the length of spire like this, with liquid when discharge portion is carried, in the process of liquid, cause bubble that cavitation produces with regard to evanescence by screw.Therefore, be difficult for producing cavitation.And in case spire prolongs, volute pump self will have higher pump capacity.

Technological scheme 13 is the bottoms that the introduction part of each described small pump device in the scheme 1 to 11 are arranged on water storage tank, and fluid passage is arranged on the outside of water storage tank, volute pump is arranged near the bottom of water storage tank.Therefore, even can realize a kind of very high electric hot water bottle of pump efficiency when not having cavitation fully or the also extremely low and delivering hot water of its probability being arranged.

It below is simple declaration to accompanying drawing.

Fig. 1 is the partial cross-sectional perspective view that the electric hot water bottle integral body of the present invention's the 1st example small pump device is equipped with in expression.

Fig. 2 is the major component sectional view of Fig. 1 electric hot water bottle.

Fig. 3 is the major component longitudinal section of the small pump device of Fig. 1.

Fig. 4 is a worm's eye view of seeing the position retaining member of Fig. 3 small pump device from arrow IV direction.

Fig. 5 is the state after the small pump device from Fig. 3 takes off impeller and screw and position retaining member.

Fig. 6 is the impeller of small pump device of the present invention's the 1st example and the side view of screw.

Fig. 7 is the VII-VII sectional view of the impeller of a presentation graphs 6.

Fig. 8 is an impeller of seeing Fig. 7 from arrow VIII direction.

Fig. 9 is an impeller of seeing Fig. 7 from arrow IX direction.

The form of Figure 10 compared on the small pump device of the present invention's the 1st example when various impellers and screw are installed, the discharge capacity of hot water and the good and bad situation relevant with refluence when usual and boiling just.

Figure 11 is the major component longitudinal section of the small pump device of the present invention's the 2nd example.

Figure 12 is the major component longitudinal section of the small pump device of the present invention's the 3rd example.

Below in conjunction with Fig. 1～Figure 10 the 1st example of the present invention is described.The small pump device 1 of the 1st example describes as the parts in the electric hot water bottle 2 of packing into.

Electric hot water bottle 2 as shown in Figures 1 and 2, mainly by the outer framework 3 that becomes shell, be arranged on water storage tank 4 that outer framework 3 inside and water storage uses and the liquid in the water storage tank 4 promoted and the small pump device 1 of discharge usefulness constitutes to the outside.

Outer framework 3 is a general cylindrical shape, is provided with bottom 3a, and water storage tank 4 is equipped with in inside, and the opening portion that forms on this water storage tank 4 is installed with switching lid 5 freely.

The front upper middle body of framework 3 outside is provided with the bottle neck portion 7 of protruding laterally, and the downside in this bottle neck portion 7 will be carried and the liquid that comes injects the opening that the water outlet 8 of usefulness such as cup is located at usefulness such as the water outlet of this downside and hot water from water storage tank 4.In addition, the outer circumferential face of framework 3 is provided with the water level indicator window 9 that shows the scale of residual liquid quantity in the water storage tank 4 at the downside of bottle neck portion 7 outside.

Water storage tank 4 is used for filling liquid for having the roughly cup-shaped of bottom 4b.In addition, be provided with electric heater 4c, by making electric heater 4c work, with the heating of the liquid in the water storage tank 4 at bottom 4b.In the outside of this water storage tank 4, be provided with the small pump device 1 that liquid is promoted usefulness to the outside.In addition, form the intercommunicating pore 4d that is communicated with small pump device at the bottom of water storage tank 4 4b.Therefore, water storage tank 4 by small pump device 1 and with the external communications of outer framework 3.

Small pump device 1 have the introduction part 10 that liquid imported from the bottom 4b of water storage tank 4, with the liquid that imports from water outlet 8 discharge usefulness discharge portion 11, connect introduction part 10 and discharge portion 11 and have coaxial setting in the fluid passage 12 of vertical tube part 12a, the vertical tube part 12a in the part and become the volute pump 13 of 2 premium on currency mechanisms and centrifugal pump 14 and as the motor 15 of driving source at fluid passage 12.

And for example shown in Figure 3, volute pump 13 and centrifugal pump 14 axially closely are being arranged on the same axle mutually.Volute pump 13 has screw 16, rotates in vertical tube part 12 by making this screw 16, forms the pump that liquid is directed to the centrifugal pump 14 on top.On the other hand, centrifugal pump portion 14 has the impeller 17 that is formed by the foliaceous member, rotates the pump that formation will be attracted and discharge by the liquid that volute pump 13 guides in vertical tube part 12a by making impeller 17.Screw 16 and impeller 17 pass through impeller 17 and the chimeric fixing one that forms of the axial region 16a of screw 16, and the rotation integratedly owing to the driving force of motor 15.

As shown in Figure 2, introduction part 10 is used to make the bottom 4b of water storage tank 4 to be communicated with the vertical tube part 12a of the fluid passage 12 that vertically is arranged on water storage tank 4 outsides, and it uses the bottom that is located at water storage tank 4, the bend pipe that is the U font to form.One end of introduction part 10 is connected with the intercommunicating pore 4d that protrudes formation at the bottom of water storage tank 4 4b, and introduction part 10 is communicated with water storage tank 4.The other end of introduction part 10 is connected with the end of the spiral pump chamber 18 of the volute pump 13 of the vertical tube part 12a lower portion that constitutes fluid passage 12.

In addition, discharge portion 11 has user's usefulness hand open and close valve 11a to be opened/closed.If the small pump device of this example 1 is connected out hot-water switch under the state that open and close valve 11a opens,, the liquid in the water storage tank 4 is promoted and discharge from water outlet 8 because the control of micro computer (omitting diagram) will drive volute pump 13 and centrifugal pump 14.In addition, the fore-end of discharge portion 11 is connected with water outlet 8, and this water outlet 8 is in the face of set discharge aperture 21 on the lower cover 20 that forms in the bottle neck portion 7.

In addition, as shown in Figure 1, fluid passage 12 is by constituting with the bottom: 2 electrodynamic type premium on currency mechanisms that the liquid of introduction part 10 imported usefulness, be that volute pump 13 and centrifugal pump 14 are arranged at coaxial vertical tube part 12a in the inboard; The discharge tube 12b that is connected with discharge oral area 14a on being located at centrifugal pump 14; Extend to the 12c of water level displaying tube portion in the bottle neck portion 7 from the vertical bending of this discharge tube 12b and fore-end; Be communicated to the interconnecting part 12d of discharge portion 11 usefulness from the 12c of water level displaying tube portion.

Vertical tube part 12a is the part of fluid passage 12 that introduction part 10 is communicated with discharge portion 11, and forms with the housing of PPS (polyhenylene sulphite) system of a part that constitutes volute pump 13 and centrifugal pump 14.That is, the part that the part that this vertical tube part 12a by the part of the screw 16 that covers volute pump 13, promptly constitutes spiral pump chamber 18 with the part of the impeller 17 that covers centrifugal pump 14, promptly constitutes centrifugal pump chamber 19 constitutes, and liquid is by its inboard space segment.

Vertical tube part 12a is that the cup-shaped member that general cylindrical shape shape, an end open wide is made by outer circumferential face as shown in Figure 3, in that end of not opening wide, be that upper end edge portion divides and forms the assembly department 12e that is bent to form laterally.This assembly department 12e becomes the part that is connected usefulness with magnet housing 22 described later.In addition, the established part of the inner peripheral surface of this vertical tube part 12a form the different usefulness of internal diameter that makes different parts stepped part 23 and with the continuous interior cup 12f of portion of stepped part 23.Vertical tube part 12a should in the 12f of cup portion constitute to cover the centrifugal pump chamber 19 of impeller 17, other parts, be the spiral pump chamber 18 that the bigger part of internal diameter constitutes covering screw 16.

In the vertical tube part 12a upper end that so constitutes, be connected and fixed the magnet housing 22 of cup-shaped, its inside is equipped with induction and is rotated the drive magnet 24 that drives usefulness with the impeller 17 of ferrite lattice formation and to impeller and screw 16.This magnet housing 22 has 2 fixing part 22a that protrude to the outside of peripheral part, makes assembly department 12e and these fixing parts 22a butt of vertical tube part 12a, and screw 22b is inserted screw hole 22c respectively, attaches it to the upper end part of vertical tube part 12a.Also be provided with a plurality of screw hole 22e at the top of magnet housing 22 22d, make the bottom 15a of motor 15 and the outside butt of this bottom 22d, under this state, screw 22f is inserted screw hole 22e, so that motor 15 is screwed.

In addition, be provided with Terminal of motor 15b in the top of motor 15 side.And on this Terminal of motor 15b, 25 connecting connector 26 by going between, this connector 26 is connected with micro computer (not shown), makes motor 15 be subjected to the drive controlling of micro computer and drives.

In addition, the central authorities at the top of magnet housing 22 22d form through hole 22g.The motor output shaft 15d that is bearing on the metal bearing 15c passes this through hole 22g.That is, through hole 22g passes for metal bearing 15c and motor output shaft 15d, and the motor output shaft 15d that is bearing on the metal bearing 15c stretches out in magnet housing 22.

Near the front end of this motor output shaft 15d, fixing discoid magnet fixed plate 24a.That is, be arranged with through hole 24b, the fore-end of motor output shaft 15d be pressed into this through hole 24b, so that magnet fixed plate 24a is fixed on the motor output shaft 15d in the rotating center section of magnet fixed plate 24a.The outer peripheral portion in the face of the side of impeller 17 at this magnet fixed plate 24a is being fixed circular drive magnet 24 with methods such as welding.In addition, in this example, drive magnet 24 uses the axial anisotropic ferrite magnet of dry type, can certainly use other magnet such as rare earth element magnet.

On the other hand, the open end by volute pump 13 1 sides of vertical tube part 12a becomes the attraction mouth 18a that attracts liquid to use.In this attraction mouthful 18a, embed position retaining member 27, and then be connected with introduction part 10 with a plurality of rib 27a.Adopt this structure, flow in the space of liquid between a plurality of rib 27a.In addition, embed sleeve pipe 28 in the attachment portion of 10 of vertical tube part 12a and introduction parts as tarpaulin.This sleeve pipe 28 adopts the silastic product that meets food hygiene law and food additives usefulness specification standards.In addition, be provided with the liquid that to attract in the side of vertical tube part 12a and carry the discharge oral area 14a of usefulness to discharge portion 11 1 sides by centrifugal pump 14 1 sides.Discharge oral area 14a at this, connecting discharge tube 12b through sleeve pipe 29.

In addition, the 12c of water level displaying tube portion of fluid passage 12 adopts the transparent glass material of drum, can see water level in the fluid passage 12 from water level indicator window 9.In addition, the attachment portion between the exhaust port 14a that forms at the discharge tube 12b that forms after the end portion bending with the 12c of water level displaying tube portion and in the side of vertical tube part 12a embeds the sleeve pipe 29 as tarpaulin.This sleeve pipe 29 adopts the silastic product that meets food hygiene law and food additives usefulness specification standards.

In the radial center part of vertical tube part 12a, fixing the straight line running shaft 30 of axial region that supports the impeller 17 of the screw 16 of volute pump 13 and centrifugal pump 14 as rotation freely.That is,, form and be pressed into the fixing part 19c that fixing straight line running shaft 30 1 ends are used at the center of vertical tube part 12a by the top 19b of centrifugal pump 14 1 sides.This fixing part 19c is made of the cylindric material that has that stretches out to volute pump 13 1 sides from bottom 19b, embeds packing ring 19d at its fore-end, and this packing ring 19d meets sliding bearing 31a, thereby becomes the set thrust plate of impeller 17 and screw 16.

On the other hand, in the end of the spiral pump chamber 18 of vertical tube part 12a, promptly attract a mouthful 18a, be provided with and embed stepped part 18b.Embed stepped part 18b at this and embed fixed position retaining member 27, the straight line running shaft 30 of the axial region of the impeller 17 of the screw 16 that supports volute pump 13 as rotation freely and centrifugal pump 14 is carried out the position keep.

Position retaining member 27 is the cylinder element that embeds at the inwall that embeds the formed vertical tube part 12a of stepped part 18b as shown in Figures 3 and 4, is provided with many roots that side direction center one side is stretched out in it, is to be provided with 3 root 27a specifically.The central part 27b that concentrates in the end of 3 root 27a of position retaining member 27 is provided with and embeds the fixing part 27c that fixing straight line running shaft 30 the other ends are used.This fixing part 27c has a round-ended cylinder shape member what central part 27b formed, and its fore-end embeds because of contact the packing ring 27d of the set thrust plate that becomes screw 16 and impeller 17 with sliding bearing 31b.

In addition, spiral pump chamber 18 that forms with above-mentioned vertical tube part 12a and centrifugal pump chamber 19 become continuous the same space as shown in Figure 5.And the internal diameter of these 2 pump chambers is inequality.That is, in the boundary part of these 2 pump chambers 18,19, form from the inwall of vertical tube part 12a to central direction protrude and with the continuous stepped part 23 of the inwall of centrifugal pump chamber 19.Like this, the internal diameter T1 of the part of the covering screw 16 of vertical tube part 12a is just greater than the internal diameter T2 of the part that covers impeller 17.

Adopt said structure, promptly, the internal diameter of spiral pump chamber 18 one sides of stepped part below 23 of vertical tube part 12a is greater than the structure of the internal diameter of centrifugal pump chamber 19 1 sides, be not use volute pump 13 and centrifugal pump 14 disjunctions for the liquid flow point that will in vertical tube part 12a, rotate by the rotation of volute pump 13 and centrifugal pump 14, because in case disjunction liquid flows like this, when the reversing by volute pump 13 made liquid return the action of water storage tank 4, liquid can not be subjected to the influence of centrifugal pump 14 and flow smoothly.

Motor 15 adopt by the driving switching of control circuit base plate (omitting diagram) can two-way rotation the DC motor, become the common driving source that the impeller 17 of the screw 16 of volute pump 13 and centrifugal pump 14 is rotated integratedly driving.

Volute pump 13 is arranged on the interior downside of vertical tube part 12a of fluid passage 12,, is arranged on the side by introduction part 10 that is.Volute pump 13 mainly is contained in spiral pump chamber 18 interior screw 16 freely by the spiral pump chamber 18 of a vertical tube part 12a part that is communicated with, becomes simultaneously fluid passage 12 with introduction part 10 and rotation and constitutes as shown in Figures 2 and 3.

Spiral pump chamber 18 is made of the part of the vertical tube part 12a of fluid passage 12, and portion is provided with rotation screw 16 freely within it.As mentioned above, the internal diameter T1 of this spiral pump chamber 18 is greater than the internal diameter T2 of centrifugal pump chamber 19.

In addition, as mentioned above, an end of spiral pump chamber 18 becomes an attraction mouthful 18a, embedded location retaining member 27 in the embedding stepped part 18b that is formed at this attraction mouthful 18a.And the 3 root 27a that form on this position retaining member 27 have following effect, i.e. the controlling liquid rotation that is directed screw rod 16 in the vertical tube part 12a of volute pump 13 attracts and the phenomenon of rotation together, with the raising pump efficiency.

In addition, screw 16 adopts PS resin materials such as (polystyrene) to make.This screw 16 is as Fig. 3 and shown in Figure 6, and the spire 16c that is provided with the axial region 16a of through hole 16b and is fixed on axial region 16a periphery integratedly by rotating center constitutes.And screw 16 is that the straight line running shaft 30 that will be fixed in the vertical tube part 12a passes through hole 16b, and is that rotating center rotates in spiral pump chamber 18 with straight line running shaft 30.In addition, this screw 16 makes liquid flow to sucking direction by rotating to a direction, and by making liquid return water storage tank 4 to the other direction rotation.

In one of the axial region 16a of screw 16 distolateral periphery, be pressed into the impeller 17 that is fixed with the PPS system.Make screw 16 and the rotation of impeller 17 one like this.In addition, be provided with the sliding bearing 31a that makes with PPS in the inboard of the through hole 16b of the axial region 16a of screw 16 end as lubricated slide member.In addition, form recess 16d in the inboard of the through hole 16b of the axial region 16a the other end.Be embedded in the sliding bearing 31b that the PPS that is used as lubricated slide member makes at this recess 16d.Adopt this structure, screw 16 is rotated under the state of two sliding bearing 31a, the 31b at clamping two ends and is bearing in freely on the straight line running shaft 30.In addition, screw 16 attracts because of the magnetic force that impeller 17 is driven magnet 24, and rotates under the state that is attracted to centrifugal pump chamber 19 1 sides all the time.In addition, the also available formations such as mixture that other members such as the carbon and the PTFE (teflon) of lubricity are arranged of sliding bearing 31a, 31b.

In addition, spire 16c by many pitch, be exactly that the helical runner 16e of 3 pitch constitutes specifically.The interior circumferential portion of these helical runners 16e is fixed on the periphery of axial region 16a integratedly, all connects into helical simultaneously, and spire 16c becomes so-called single-screw.This single-screw structure be with the pitch of each helical runner 16e at interval L do fully greatly (in this example pitch L=7.5mm) at interval, in order to ensure the pump capacity of volute pump 13.The angle of lead α of the spire 16c of the screw 16 of this example is 8.43 °, and the angle of lead of spire 16c is suitable for getting 5～15 ° scope, wherein is best more than 8 °.

In addition, to make the external diameter W1 of helical runner 16e be 24mm to the spire 16c of the screw 16 of this example.This outside dimension is greater than the 17mm of the outside dimension W2 of impeller 17, the outside dimension W2 of impeller 17 be helical runner 16e outside dimension 20～80%.This structure reverses impeller 17 and screw 16 so that the liquid in the fluid passage 12 when flowing back to water storage tank 4, can alleviate the influence that impeller 17 causes integratedly, and liquid is flow backwards.

That is, during reversing, form spiral helicine spire 16c reversing, the liquid in the vertical tube part 12a will be flow backwards along spire 16c, but because the also together rotation of impeller 17 this moment, so liquid is pulled to discharge portion 11 1 sides owing to the rotation of impeller 17.Yet, when adopting the small pump device 1 of this example, as mentioned above because the external diameter W2 of impeller 17 is less than the external diameter W1 of screw 16, so the time attraction force a little less than, can too much influence not arranged to the refluence of liquid.For this reason, in the small pump device 1 of this example, liquid is successfully flow backwards.

In addition, above-mentioned screw 16 be 27mm along the axial total length L1 of spire 16c, slightly longer than traditional product.Like this, even the liquid of boiling will gasify by volute pump 13 time, in by the process of spire 16c, also can cool off and become liquid again.Like this, the small pump device 1 of this example just can not delivered to the steam that becomes bubble near the impeller 17,, is difficult for producing cavitation that is.In addition, if the entire axial length of screw 16 is made more than the 25mm, then can realize above-mentioned effect.Also have, the upper limit of total length is according to changing in size longitudinally for the frameworks such as vacuum bottle of installing.

On the other hand, centrifugal pump 14 is arranged on the interior upside of vertical tube part 12a of fluid passage 12.That is, centrifugal pump 14 mainly constitutes by being communicated with, becoming simultaneously the centrifugal pump chamber 19 of a vertical tube part 12a part and rotate the impeller 17 that is contained in freely in the centrifugal pump chamber 19 with the discharge tube 12b of fluid passage 12.

Centrifugal pump chamber 19 is made of the part of the vertical tube part 12a of fluid passage 12, and portion is provided with rotation impeller 17 freely within it.As mentioned above, the internal diameter T2 of this centrifugal pump chamber 19 is less than the internal diameter T1 of spiral pump chamber 18.

Fixing above-mentioned magnet housing 22 at an end of this centrifugal pump chamber 19,, making impeller 17 follow drive magnet 24 rotations by drive magnet 24 rotations.Make screw 16 and the rotation of impeller 17 one like this.

On the inwall of centrifugal pump chamber 19, formation is communicated with the discharge tube 12b of fluid passage 12 with discharging oral area 14a in addition.Therefore, the liquid that is attracted in the vertical tube part 12a by the attraction force of volute pump 13 and centrifugal pump 14 is just discharged to discharge portion 11 from discharging oral area 14a.On the other hand, in case with volute pump 13 and centrifugal pump 14 reverse drivings, the liquid in discharge tube 12b and the 12c of water level displaying tube portion just flows back in the vertical tube part 12a by discharging oral area 14a.

Impeller 17 is as Fig. 3, Figure 6 and Figure 7, the stepped part 17b that more extends outside by axial region 17a, from the outer peripheral portion of axial region 17a one end, constitutes at 2 blade 17d that the outer circumferential face of axial region 17a forms with the continuous cylindrical part 17c roughly cylindraceous of this stepped part 17b, scope from the other end of axial region 17a to stepped part 17b.

On axial region 17a, be provided with the through hole 17e that the fore-end of the axial region 16a of screw 16 is pressed into usefulness.As shown in Figure 8 at the intake section of this through hole 17e, be the end of axial region 17a in the face of screw 16, be provided with rake 17f that the axial region 16a of being convenient to screw 16 inserts and the rotation prevention portion 17g that is pressed into the back spline.Impeller 17 embeds the fore-end periphery of the axial region 16a of screw 16 by said structure, rotates with screw 16 one.

In addition, as shown in Figure 9,, on impeller 17, carry out alternately 4 pole-faces magnetization of each NS of 90 ° in order to be subjected to the magnetic induction of the drive magnet 24 in magnet housing 22.Intersection at the N utmost point and the S utmost point forms slit 17h respectively, has the effect that the magnetic leakage to circumferencial direction is sealed.Therefore, in case motor 15 drives and motor output shaft 15d rotation, the 17b of impeller portion just is driven magnet 24 magnetic induction, just rotation in centrifugal pump chamber 19 of impeller 17.In case and impeller 17 rotation, 2 blade 17d just make the liquid in rotation in the centrifugal pump 19.In addition, the rotating center at impeller 17 produces negative pressure.Because this effect has just produced the power that air in the vertical tube part 12a and liquid etc. is attracted to rotating center.

In addition, the outside dimension W2 of impeller 17 is 17mm, is in 20～80% the scope of the 24mm of the outside dimension W1 of above-mentioned screw 16.This is to compare with traditional product because consider the small pump device 1 of this example, along with the pump capacity raising of volute pump 13, the pump capacity of centrifugal pump 14 can be too big, and when liquid is flow backwards, centrifugal pump 14 to attraction force that liquid is discharged direction a little less than, can successfully flow backwards.

Along with relative raising of pump capacity phase specific energy of pump capacity with the centrifugal pump 14 of this volute pump 13, that is, volute pump 13 can be carried liquid during refluence under the condition that not too much influenced by centrifugal pump 14, and this example can be with volute pump 13 and centrifugal pump 14 near being provided with.Therefore, the small pump device 1 of this example can shorten the axial dimension of the vertical tube part 12a with pumping function, can be used for various devices (for example shorter water bottle etc.).As a result, increase versatility, needn't produce the product that is suitable for certain vacuum bottle device more specially in batches, be suitable for a large amount of productions.

Performance when the small pump device 1 that Figure 10 has compared above-mentioned example uses above-mentioned screw 16 and impeller 17 when using other 6 kinds of screw and impeller below describes particularly.In addition, pump capacity etc. change according to the gap between screw or impeller outer circumference end and housing and other conditions, are to describe under the same conditions among the figure.

Table among Figure 10 is in the 1. hot water discharge capacity usually the time, the discharge capacity, the performance that 3. flows backwards under these 3 kinds of user modes separately of hot water compares when 2. just having seethed with excitement to each Sample A～G.

After use when so-called 1. common is the liquid boiling of instigating in the water storage tank 4,, promptly under " insulation " state, pushes discharge button (omit and illustrate) liquid is discharged from water outlet 8 through certain hour.In this occasion, because hot water is not the state that gasifies easily, so can not produce the problem relevant with air pocket, pump performance is basic only relevant with its attraction force.

So-called use when 2. just having seethed with excitement is meant by electric heater 4c with the heating of the liquid in the water storage tank 4 and make it boiling, and pushes immediately and discharge button (omitting diagram), and liquid is discharged from water outlet 8.In this occasion, hot water gasifies easily, and cavitation takes place easily.Therefore, in order to ensure discharge capacity, need to adopt the structure that suppresses the air pocket generation on the small pump device 1.

3. what is called flows backwards, the discharge button (omit diagram) that is meant electric hot water bottle 2 for a long time need not, the method for using during liquid cooling in the fluid passage 12 is promptly pressed refluence button (omitting diagram) liquid in the fluid passage 12 is flowed back in the water storage tank 4.That is, when time spent not for a long time, if press the discharge button under this state, chilled liquid will be discharged from water outlet 8.And this using method promptly is in order to prevent this phenomenon.

In addition, the expression sufficient evaluation mark of pump capacity (zero) be meant 10 seconds of the discharge button of pressing electric hot water bottle 2 (omitting diagram) back with the discharge capacity of " boiling liquid " of interior discharge greater than more than the 400ml.And the evaluation mark (△) of expression pump capacity deficiency is meant that discharge capacity is below half of evaluation mark (zero), promptly press discharge 10 seconds behind the button with the discharge capacity of " liquid of boiling " of interior discharge less than 200ml.But, evaluation mark (△) though discharge capacity few, what discharge is the liquid of boiling.In addition, expression does not have the evaluation mark (*) of pump capacity fully even be meant and press the discharge button, not have the situation of the liquid discharge of boiling fully yet.These 3 kinds of evaluation marks (zero) (△) (*) all are used for Sample A, B, C, D, E, F equally.

In the table of Figure 10, Sample A is used the screw 16 and the impeller 17 of this example.That is, the terms and conditions of the spire 16c of screw 16 is: external diameter=24mm, single-screw, angle of lead=8.43 ° as mentioned above, and the external diameter of pitch interval=7.5mm, entire axial length=27mm, impeller 17 is 17mm.

When the Sample A of structure like this was used for small pump device 1, the pump capacity (discharge capacity) in the time of usually was abundant, and it is evaluated as (zero).Even Sample A can not produce cavitation yet when boiling just, pump capacity (discharge capacity) is abundant, and its evaluation mark is (zero).Sample A is when flowing backwards, and its evaluation mark also is (zero).

In addition, in the table of Figure 10, sample B just with above-mentioned the 1st example, be that the impeller outer diameter of Sample A has been done change.That is, the terms and conditions of the spire of the screw of sample B is all identical with Sample A, and just the external diameter of impeller is 23mm greater than Sample A.The terms and conditions of the spire of sample B is specially: external diameter=24mm, single-screw, angle of lead=8.43 °, and pitch interval=7.5mm, entire axial length=27mm.As a result, though the impeller outer diameter of sample B less than the external diameter of spire, its ratio is greater than 80%.

When the sample B with said structure was used for small pump device 1, the pump capacity (discharge capacity) in the time of usually was evaluated as (zero).In addition, even sample B can not produce cavitation yet when boiling just, pump capacity (discharge capacity) evaluation mark is (zero).Yet sample B is when flowing backwards, and its evaluation mark is an expression pump capacity inadequate (△).At this moment because impeller outer diameter increases, its rotating force has influenced refluence.

In addition, in the table of Figure 10, sample C is with above-mentioned the 1st example, is that the external diameter of spire of Sample A and the external diameter of impeller have been done change.That is, the spire external diameter of the screw of sample C is that the external diameter of 18.2mm, impeller is 23mm.In addition, other conditions of spire are all identical with Sample A, and the terms and conditions of the spire of sample C is specially: single-screw, angle of lead=8.43., pitch interval=7.5mm, entire axial length=27mm.As a result, the impeller outer diameter of sample C is greater than the external diameter of spire.

So the sample C of structure is that pump capacity (discharge capacity) is estimated (zero) fully usually the time under the situation that is used for small pump device 1.In addition, even sample C just after the boiling air pocket is not taking place yet, be that pump capacity (discharge capacity) is estimated (zero) fully.But, about the refluence of sample C, become be can not evaluation (*).This is because following cause: though the external diameter of impeller self is identical with sample B, because that the external diameter of screw is compared with sample B is less, therefore, the influence that rotating force produced of the impeller during refluence is just bigger than sample B.

In addition, in the table of Figure 10, sample D is to only the angle of lead of spire being given structure after changing in the Sample A of above-mentioned the 1st example.And owing to change angle of lead less, the pitch of each screw rod must become narrow and small at interval.That is, each condition of the spire of the screw of sample D is: external diameter=24mm; Single-screw; Angle of lead=4.07 °; Pitch interval=3.6mm; Entire axial length=27mm, and the external diameter of impeller 17 is 17mm.

So the sample D of structure is the inadequate evaluation of pump capacity (discharge capacity) (△) usually the time under the situation that is used for small pump device 1.This is because the cause that the angle of lead of spire is less, thereby the narrow and small at interval pump capacity self that makes volute pump usually time of the pitch of each screw rod descends.In addition, even sample D also is the evaluation (*) of no pump capacity (discharge capacity) after boiling just.Its reason is, be not because air pocket takes place, but original pump capacity is low.In addition, the evaluation after the boiling why evaluation when common is poor, is to be difficult to attract liquid because the state after the boiling is compared when common, thereby influences the low of pump capacity more.In addition, about the refluence of sample D, also be become can not evaluation (*).This is because the pump capacity of sample D lowly also has influence on the cause that liquid is sent to opposite direction.

In addition, in the table of Figure 10, sample E be the angle of lead with the spire of said sample D change bigger slightly structure.And the angle of lead of the spire of sample E is littler than the angle of lead of said sample A, and therefore, the pitch of screw rod is narrower and small than sample A at interval.That is, each condition of the spire of the screw of sample E is: external diameter=24mm; Single-screw; Angle of lead=5.65 °; Pitch interval=5.0mm; Entire axial length=27mm, and the external diameter of impeller 17 is 17mm.

So the sample E of structure is that pump capacity (discharge capacity) is estimated (zero) fully usually the time under the situation that is used for small pump device 1.In addition, even after boiling just, also being pump capacity (discharge capacity), sample E estimates (zero) fully.Its result, when liquid being sent into discharge portion 11 sides, because volute pump and centrifugal pump synergy, so, we can say also can not cause what influence to pump capacity even the angle of lead of spire is slightly little.But,, also be to become inadequate evaluation (△) about the refluence of sample E.This is because following cause: centrifugal air pump inoperative depends on the pump capacity of screw during owing to refluence, so the angle of lead of spire is slightly little and the evaluation of the sample E that the pitch of each screw rod interval is narrow and small slightly becomes low slightly.

Sample F, the G that the following describes is the structure that only entire axial length of the spire of above-mentioned Sample A is changed, and other all conditions are identical with Sample A.That is, each condition of the spire of the screw of sample F, G all is: external diameter=24mm; Single-screw; Angle of lead=8.43 °; Pitch interval=7.5mm; And the external diameter of impeller 17 is 17mm, and for entire axial length, sample F is 17mm, and sample G is 37mm.

So, for sample F discharge capacity and the refluence usually time shorter of the total length of spire, all be sufficient evaluation (zero) than sample A, when for the discharge capacity after the boiling, the generation air pocket, be can not drain evaluation (*).This is because following cause: because spire is axially shorter, so after the boiling gas of gasification spire by in do not revert back to liquid, the air after keeping expanding passes in and out at the rotating center place of impeller.In addition, shown in sample G, doing the entire axial length of spire than long structure, in the discharge capacity after discharge capacity usually time the and the boiling and all projects of refluence, is sufficient evaluation (zero).Therefore, doing the long shortcoming that is produced by the total length of spire, is ineffable with viewpoints such as pump capacities.But, when spire is elongated, owing to the restriction in the design also increases, so in this example, make said structure.

In addition, said sample A, be that the spire 16c of the screw 16 of this example makes 8.43 ° of angle of lead, pitch interval=7.5mm, entire axial length=27mm, but because these above-mentioned evaluations are (zero) or (*), so also variable other numerical value of one-tenth.Above-mentioned each estimated, and is not absolute, and what numerical value to make it to become (zero) with is arbitrarily.

Below, the action of just assembling the electric hot water bottle 2 behind above-mentioned such design of mini pump-unit 1 describes.

At first, as the warming-up exercise of boiling, will cover 5 and open water is put into water storage tank 4.Like this, a part of water of putting into water storage tank 4 is directed to introduction part 10 from intercommunicating pore 4d, debouches in the fluid passage 12.At this moment, cutting off the water supply according to the position of capacity of the water of putting into water storage tank 4, the position of the water surface of the 12c of water level displaying tube portion of fluid passage 12 can see from water level indicator window 9, thus, can estimate the inner capacities that water storage tank 4 is interior.That is, under this state, water enters in the vertical tube part 12a of fluid passage 12 fully, immerses the part midway of water storage tank 4 and fluid passage 12 up to water.

Under state like this,, the water in the water storage tank 4 are heated to electric heater 4c energising.During the water boiling, the steam that produce this moment is discharged to the outside from being located at the steam hole 5a that covers on 5.

When boiling water is discharged, under the state of opening open and close valve 11a, discharge button (not shown), and the motor 15 of the driving source that becomes DYN dynamic premium on currency mechanism is driven to direct rotational direction by operation.Like this, the motor output shaft 15d that has fixed drive magnet 24 rotates to postive direction in magnet housing 22.

So when drive magnet 24 when postive direction is rotated, the impeller 17 that is magnetized on the cylindrical part 17c is bearing on the straight line running shaft 30, and rotates to postive direction integratedly with screw 16.Like this, liquid rotatablely moves because of the rotation of screw 16 and impeller 17 produces, and along with the motion of this liquid, the boiling water of water storage tank 4 is inhaled into vertical tube part 12a from attracting a mouthful 18a, discharges from discharging oral area 14a again.Boiling water after the discharge is through discharge tube 12b, the 12c of water level displaying tube portion of fluid passage 12 and interconnecting part 12d and be directed into discharge portion 11.And this moment, because the open and close valve 11a of discharge portion 11 by opening, so boiling water moves to water outlet 8 from discharge portion 11, discharges to the outside from water outlet 8.

In addition, in path as described above, when the liquid in the water storage tank 4 when water outlet 8 is discharged, initial, be placed on not heated water in the fluid passage 12 for a long time to discharge portion 11 side shiftings, discharge from water outlet 8.And, follow at boiling water not heated cold water back, after in water storage tank 4, being heated and can supply with to water outlet 8 directions because of the rotation of screw 16 and impeller 17.

In addition, the boiling water in the water storage tank 4, under the situation as the boiling water after the boiling, the boiling water that is near the temperature of boiling point produces gasification, or bubble produces and expand, thereby has the rotating center of generation impeller 17 to be full of the anxiety of the cavitation of air.But, in this example, owing to come continuously boiling water to be supplied in the rotating center of impeller 17 by the screw 16 that is difficult to produce above-mentioned air pocket, so be difficult to produce cavitation.

In addition, be under the situation of cold water disliking initial water of discharging, that is, under the situation of the initial 1 glass of hot boiling water of needs, can carry out following mode initialization and deal with.That is to say,, just can make motor 15 in the other direction to driving by the operating provision button.In addition, as mentioned above, the impeller 17 of this example, owing to make the structure of the refluence of liquid not being brought influence when counter-rotating, screw 16 can send back to water storage tank 4 sides with the water in the fluid passage 12 rapidly.

Thus, at the not heated water in water storage tank 4 outsides, with the state of boiling water after being mixed into heating of boiling in water storage tank 4.Then, motor 15 automatically drives to postive direction, just discharges hot boiling water at first.In addition, also can not dispose so mode initialization function, and the sort of structure of configuration return push-button (diagram is omitted) is done to drive, and then, pushes the discharge button in the other direction according to its action.

In addition, the occasion cleaning electric hot water bottle 2 is performed as follows.At first, open and cover 5, an amount of water is put into water storage tank 4, so a part of water of putting into water storage tank 4 is directed to introduction part 10 from intercommunicating pore 4d, increases to fluid passage 12.

Under state like this, washing agent is put into water storage tank 4, the operation incrustation scale cleans button (not shown), so, to electric heater 4c energising, the water in the water storage tank 4 is heated.With this heating in or after the boiling, make that motor 15 is contrary to be driven rotatably.Thus, the water in the fluid passage 12 is returned in the water storage tank 4.After to a certain degree the timing or certain hour, then motor 15 is made positive rotation in water turns back to water storage tank 4.So the boiling water of putting into washing agent in the water storage tank 4 is drawn onto fluid passage 12 sides.By action so repeatedly, the inside of the major component of the fluid passage 12 of electric hot water bottle 2, promptly the periphery of impeller 17 peripheries and volute pump 13 and introduction part 10 etc. are just cleaned.

In addition,, be not limited thereto, in the scope that does not break away from aim of the present invention, can do various distortion though above-mentioned example is the example of preferable example of the present invention.For example, in above-mentioned small pump device 1, be the internal diameter T1 of spiral pump chamber 18 greater than the internal diameter T2 of centrifugal pump chamber 19, by the liquid stream in stream of the liquid in the disjunction spiral pump chamber 18 and the centrifugal pump chamber 19, can reduce the influence of centrifugal pump 14 when then flowing backwards, the liquid in the fluid passage 12 successfully can be turned back to water storage and irritate 4 sides, and the structure of the inwall of vertical tube part 12a is so long as carry out in volute pump and centrifugal pump respectively that disjunction uses, any part can be done greatly, also any part can be done little.Other examples are explained as follows as the 2nd example and the 3rd example.In addition, for the same structure division of above-mentioned the 1st example, use same-sign, the detailed description of the part beyond the major component is omitted.

As shown in figure 11, the small pump device 41 of the 2nd example is, the internal diameter T2 ' of centrifugal pump chamber 49 is greater than the internal diameter T1 ' of spiral pump chamber 48, and identical with the 1st example, has: vertical tube part 42a; Be configured in the volute pump that is provided with screw 46 43 in the vertical tube part 42a and be provided with the centrifugal pump 44 of impeller 47; As the rotatable motor 45 of the both sides of driving source.

Vertical tube part 42a is the part of the fluid passage 12 that is connected with the introduction part 10 and the discharge portion 11 of above-mentioned the 1st example, and is formed by the casing of a part that constitutes volute pump 43 and centrifugal pump 44.Promptly, this vertical tube part 42a be by the part of the screw 46 that covers volute pump 43, promptly constitute the part of spiral pump chamber 48 and cover the part of the impeller 47 of centrifugal pump 44, the part that promptly constitutes centrifugal pump chamber 49 constituted, and becomes the structure of liquid by inboard space segment.

The outer circumferential face of vertical tube part 42a is the general cylindrical shape shape, and is distolaterally formed by open cup-shaped member by one, at a unopened side end, be that the upper end edge portion branch is formed with assembly department 42e.On this assembly department 42e, be fixed with magnet housing 52, accommodate in these magnet housing 52 inside guiding impeller 47, be used for rotating the drive magnet 54 of drives impeller 47 and screw 46.Have outstanding laterally fixing part 52a at the peripheral part of this magnet housing 52, make assembly department 42e and these fixing parts 52a butt of vertical tube part 42a, by with in the screw 42b insertion screw hole 42c, and be installed on the upper end part of vertical tube part 42a.In addition, on the 52d of the top of magnet housing 52, be provided with a plurality of screw hole 52e, under the state of the outside butt of the bottom 45a that makes motor 45 and this top 52d, be screwed motor 45 by will screw 52f inserting in the screw hole 52e.

In addition, in the central authorities of the top of magnet housing 52 52d, be formed with through hole 52g.In this through hole 52g, connect and be inserted with the motor output shaft 45d that is bearing on the metal bearing 45c.That is, through hole 52g is used for connecting and inserts metal bearing 45c and motor output shaft 45d, and the motor output shaft 45d that is bearing on the metal bearing 45c stretches in the magnet housing 52.

Front end at this motor output shaft 45d is fixed with discoid magnet fixed plate 54a.That is, be arranged with through hole 54b,, magnet fixed plate 54a can be fixed on the motor output shaft 45d by motor output shaft 45d fore-end is pressed into this through hole 54b in the rotating center section of magnet fixed plate 54a.At outer peripheral portions this magnet fixed plate 54a and faces impeller 47 opposite sides, utilize mode such as bonding to be fixed with circular drive magnet 54.

In addition, the open sides of volute pump 43 sides of vertical tube part 42a becomes the attraction mouth 48a that is used for attracting liquid.Embedding in this attraction mouthful 48a has the position retaining member 51 with a plurality of rib 51a, and connects introduction part 10.Utilize this structure, liquid just can be by the space of a plurality of rib 51a between mutually.In addition, embed the pipe 58 that has as waterproof cover in attachment portion vertical tube part 42a and introduction part 10.And, be provided with the liquid after attracting is sent to the discharge oral area 44a that discharge portion 11 sides are used in the side of centrifugal pump 44 sides of vertical tube part 42a.On this discharge oral area 44a, connect discharge tube 12b by pipe (not shown).

In the radial center part of vertical tube part 42a, be fixed with as the screw 46 of volute pump 43 and the impeller 47 of centrifugal pump 44 are rotated the straight line running shaft 60 of the axial region of supporting freely.That is, at the 49b center, bottom of centrifugal pump 44 sides of vertical tube part 42a, an end that is formed with straight line running shaft 60 is pressed into the fixedly fixing part 49c of usefulness.This fixing part 49c is by being constituted to the volute pump 43 side-prominent drums that the end is arranged from bottom 49b, and embedding to have by meeting sliding bearing 61a at its fore-end becomes the packing ring 49d of the axial baffle of impeller 47 and screw 46.

On the other hand, in the end of the spiral pump chamber 48 of vertical tube part 42a, promptly attract a mouthful 48a place to be provided with embedding stepped part 48b.Embed on the stepped part 48b at this, embed to be fixed with straight line running shaft 60 is carried out the position retaining member 51 that the position keeps usefulness, this straight line running shaft 60 is as the screw 46 of volute pump 43 and the impeller 47 of centrifugal pump 44 are rotated the axial region of supporting freely.

Position retaining member 51 comprises: imbed the circular chimeric ring portion 51e that embeds stepped part 48b and form; From the outstanding rib 51a of interior all side direction central sides of chimeric ring portion 51e; Extend axially the cylindrical part 51f of the inwall that constitutes spiral pump chamber 48 from the interior Zhou Duanxiang of chimeric ring portion 51e; From the fore-end bending of cylindrical part 51f and towards the bending part 51g of the inwall of vertical tube part 42a.In addition, the central part 51b in that concentrate the end of a plurality of rib 51a of position retaining member 51 is provided with and is used for embedding the fixedly fixing part 51c of the other end of straight line running shaft 60.This fixing part 51c is made of the cylindrical structural member that the end is arranged that is formed on the central part 51b, and embedding to have by meeting sliding bearing 61b at fore-end becomes the packing ring 51d of the axial baffle of screw 46 and impeller 47.

As mentioned above, in the small pump device 41 of the 2nd example, owing on position retaining member 51, be set to the cylindrical part 51f and the bending part 51g of the inwall of spiral pump chamber 48, so the internal diameter T1 ' of spiral pump chamber 48 is narrower and small than the internal diameter T2 ' of centrifugal pump chamber 49.

This structure, promptly the internal diameter of vertical tube part 42a is begun to make the internal diameter T2 ' of centrifugal pump chamber 49 sides of upside greater than the structure of the internal diameter T1 ' of spiral pump chamber 48 sides from bending part 51g, identical with the 1st example, be to utilize the rotation of volute pump 43 and centrifugal pump 44 and by volute pump 43 and centrifugal pump 44 liquid mobile of doing rotation in the vertical tube part 42a given disjunction respectively and use.So, in case the flowing of disjunction liquid, then when the contrary rotation that utilizes volute pump 43 made liquid to action that water storage tank 4 sides are returned, liquid that can not was subjected to the influence of centrifugal pump 44 and successfully flows backwards.

Volute pump 43 mainly comprises: with when introduction part 10 is communicated with and become the spiral pump chamber 48 of the vertical tube part 42a part of fluid passage 12; Rotation is contained in the screw 46 in the spiral pump chamber 48 freely.As mentioned above, the internal diameter T1 ' of this spiral pump chamber 48 is less than the internal diameter T2 ' of centrifugal pump chamber 49.In addition, the structure of screw 46 is identical with above-mentioned the 1st example, by becoming to direction rotation to the direction that sucks liquid, by vividly doing to the direction real estate that makes liquid turn back to water storage tank 4 sides to the other direction rotation.

Be pressed in the distolateral periphery of the axial region 46a of screw 46 and be fixed with impeller 47.Therefore, screw 46 is the one rotation with impeller 47, is disposed in clamping under the state of two sliding bearing 61a, 61b at two ends, and rotation is bearing on the straight line running shaft 60 freely.

On the other hand, centrifugal pump 44 mainly comprises: with when the discharge tube 12b of fluid passage 12 is communicated with and become the centrifugal pump chamber 49 of the part of vertical tube part 42a; Rotation is contained in the impeller 47 in the centrifugal pump chamber 49 freely.As mentioned above, the internal diameter T2 ' of centrifugal pump chamber 49 is greater than the internal diameter T1 ' of spiral pump chamber 48.

As mentioned above, at a distolateral magnet housing 52 that the drive magnet 54 with the rotation of the motor output shaft 45d one of motor 45 is held that is fixed with of this centrifugal pump chamber 49, by rotation drive magnet 54, impeller 47 just rotates along with drive magnet 54.Thus, screw 46 is just rotated with impeller 47 one.

In addition, on the inwall of centrifugal pump chamber 49, be formed with the discharge oral area 44a that is communicated with usefulness with the discharge tube 12b of fluid passage 12.Therefore, the liquid that sucks in the vertical tube part 42a is discharged to discharge portion 11 sides from discharging oral area 44a because of the attraction force of volute pump 43 and centrifugal pump 44.On the other hand, when driving volute pump 43 and centrifugal pump 44 to opposite direction, the liquid in discharge tube 12b and the 12c of water level displaying tube portion flows back in the vertical tube part 42a by discharging oral area 44a.And impeller 47 has and the same structure of above-mentioned the 1st example, makes motor output shaft 45d when rotation when drive motor 45, produces magnetic induction and be rotated in centrifugal pump chamber 49 on drive magnet 54.And, when impeller 47 rotations, both can make the liquid in rotation in the centrifugal pump chamber 49, can in vertical tube part 42a, produce the power that attracts air or liquid etc. again.

As shown in figure 12, the small pump device 71 of the 3rd example, the internal diameter T1 of its spiral pump chamber 78 " with the internal diameter T2 of centrifugal pump chamber 79 " be same diameter, and the part between spiral pump chamber 78 and centrifugal pump chamber 79, has the jut 91a that the internal diameter that makes vertical tube part 72a dwindles, and spiral pump chamber 78 and centrifugal pump chamber 79 are respectively by disjunction, make liquid when action that water storage tank 4 sides are returned when the contrary rotation that utilizes screw 76, liquid that can not is subjected to the influence of centrifugal pump 44 and can successfully flows backwards.In addition, identical with the 1st and the 2nd example, it has: vertical tube part 72a; Be configured in the volute pump that is provided with screw 76 73 in the vertical tube part 72a and be provided with the centrifugal pump 74 of impeller 77; The motor 75 that rotates as the made both sides of driving source.

Vertical tube part 72a makes the 1st housing 80 of tubular roughly and the 2nd housing 81 forms an inner space axially connecting structure, be and the above-mentioned the 1st and the introduction part 10 of the 2nd example and the part of the fluid passage 12 that discharge portion 11 is communicated with, and constitute the part of volute pump 73 and centrifugal pump 74.Promptly, this vertical tube part 72a by the part of the screw 76 that covers volute pump 73, promptly constitute the part of spiral pump chamber 78 and cover the part of the impeller 77 of centrifugal pump 74, the part that promptly constitutes centrifugal pump chamber 79 constituted, and becomes the structure of liquid by inboard space segment.

The 1st housing 80 of vertical tube part 72a, its outer circumferential face is the general cylindrical shape shape, and is formed by the cup-shaped member of a distolateral opening, at a unopened side end, be that the upper end edge portion branch is formed with assembly department 72e.On this assembly department 72e, be fixed with magnet housing 82, accommodate in these magnet housing 82 inside induction impeller 77, be used for rotating the drive magnet 84 of drives impeller 77 and screw 76.Have outstanding laterally fixing part 82a at the peripheral part of this magnet housing 82, make assembly department 72e and these fixing parts 82a butt of vertical tube part 72a, by with in the screw 72b insertion screw hole 72c, and be installed on the upper end part of vertical tube part 72a.In addition, on the 82d of the top of magnet housing 82, be provided with a plurality of screw hole 82e, under the state of the outside butt of the bottom 75a that makes motor 75 and this top 82d, be screwed motor 75 by will screw 82f inserting in the screw hole 82e.

In addition, the central authorities at the top of magnet housing 82 82d are formed with through hole 82g.In this through hole 82g, connect and be inserted with the motor output shaft 75d that is bearing on the metal bearing 75c.That is, through hole 82g is used for connecting and inserts metal bearing 75c and motor output shaft 75d, and the motor output shaft 75d that is bearing on the metal bearing 75c stretches in the magnet housing 82.

Front end at this motor output shaft 75d is fixed with discoid magnet fixed plate 84a.That is, be arranged with through hole 84b,, magnet fixed plate 84a can be fixed on the motor output shaft 75d by motor output shaft 75d fore-end is pressed into this through hole 84b in the rotating center section of magnet fixed plate 84a.At outer peripheral portions this magnet fixed plate 84a and faces impeller 77 opposite sides, utilize mode such as bonding to be fixed with circular drive magnet 84.

On the other hand, the open end at the 1st housing 80 of vertical tube part 72a is formed with and is close to the recess 80a that fixes the 2nd housing 81 usefulness.By being close to the stepped part 81a that fixes the 2nd housing 81, and the 1st housing 80 and the 2nd housing one are fixed, constituted vertical tube part 72a at the inner face of this recess 80a.

In addition, the open end of introduction part 10 sides of the 2nd housing 81 of vertical tube part 72a becomes the attraction mouth 78a that attracts liquid to use.Attract to embed the position retaining member 83 that a plurality of rib 83a are arranged among mouthful 78a at this, and connect introduction part 10.Utilize this structure, liquid just can circulate in the space between a plurality of rib 83a are mutual.And embed the pipe 88 that has as waterproof cover in attachment portion vertical tube part 72a and introduction part 10.In addition, in the side of centrifugal pump 74 sides of vertical tube part 72a, be provided with the discharge oral area 74a that the liquid after attracting is sent usefulness to discharge portion 11 sides.Discharge on the oral area 74a by pipe (not shown) connection discharge tube 12b at this.

On the other hand, near the end of the 1st housing 80 sides of the 2nd housing 81, be formed with stepped part 81a, be close in the recess 80a of the 1st housing 80, just can be fixed on integratedly on the 1st housing 80 by this stepped part 81a is embedded.In addition, at the fore-end of the stepped part 81a of the 2nd housing 81, it is outstanding and make the internal diameter of vertical tube part 72a dwindle the protuberance 91a of usefulness to be formed with center side to vertical tube part 72a.

This structure, promptly the part of the internal diameter of vertical tube part 72a is made the structure littler than other parts by protuberance 91a is set, identical with the 1st and the 2nd example, be to utilize the rotation of volute pump 73 and centrifugal pump 74 and the liquid flow point of doing rotation is not used by volute pump 73 and centrifugal pump 74 disjunctions.So, in case the flowing of disjunction liquid, then when the contrary rotation that utilizes volute pump 73 made liquid to action that water storage tank 4 sides are returned, liquid that can not was subjected to the influence of centrifugal pump 74 and successfully flows backwards.

In the radial center part of the vertical tube part 72a that so constitutes, be fixed with as the screw 76 of volute pump 73 and the impeller 77 of centrifugal pump 74 are rotated the straight line running shaft 90 of the axial region of supporting freely.That is, at the 79b center, top of centrifugal pump 74 sides of vertical tube part 72a, an end that is formed with straight line running shaft 90 is pressed into the fixedly fixing part 79c of usefulness.This fixing part 79c is by being constituted to the volute pump 73 side-prominent circle tube members that the end is arranged from top 79b, and embedding to have by meeting sliding bearing 92a at its fore-end becomes the packing ring 79d of the axial baffle of impeller 77 and screw 76.

On the other hand, in the end of the spiral pump chamber 78 of vertical tube part 72a, promptly attract a mouthful 78a place to be provided with embedding stepped part 78b.Embed on the stepped part 78b at this, embed to be fixed with straight line running shaft 90 is carried out the position retaining member 83 that the position keeps usefulness, this straight line running shaft 90 is as the screw 76 of volute pump 73 and the impeller 77 of centrifugal pump 74 are rotated the axial region of supporting freely.

Position retaining member 83 comprises: imbed the circular chimeric ring portion 83e that embeds stepped part 78b and form; From the outstanding rib 83a of interior all side direction central sides of chimeric ring portion 83e.Central part 83b in that concentrate the end of rib 83a is provided with and is used for embedding the fixedly fixing part 83c of the other end of straight line running shaft 90.This fixing part 83c is made of the cylindrical structural member that the end is arranged that is formed on the central part 83b, and embedding to have by meeting sliding bearing 92b at fore-end becomes the packing ring 83d of the axial baffle of screw 76 and impeller 77.

In the small pump device 71 of the 3rd example, as mentioned above, on the 2nd housing 81, between spiral pump chamber 78 and centrifugal pump chamber 79, form to the outstanding protuberance 91a of the central side of vertical tube part 72a.Therefore, the internal diameter T1 that forms spiral pump chamber 78 with same diameter " reaches internal diameter T2 of centrifugal pump chamber 79 ", and protuberance 91a forms internal diameter T3 " less than these diameters T1 ", the T2 of part ".

Volute pump 73 mainly comprises: with when introduction part 10 is communicated with and become the spiral pump chamber 78 of the vertical tube part 72a part of fluid passage 12; Rotation is contained in the screw 76 in the spiral pump chamber 78 freely.As mentioned above, the internal diameter T1 of this spiral pump chamber 78 " with the internal diameter T2 of centrifugal pump chamber 79 " is identical, and forms the internal diameter T3 of part greater than protuberance 91a ".In addition, the structure of screw 76 is identical with the above-mentioned the 1st and the 2nd example, by becoming to direction rotation to the direction that sucks liquid, by vividly doing to the direction real estate that makes liquid turn back to water storage tank 4 sides to the other direction rotation.

Be pressed in the distolateral periphery of the axial region 76a of screw 76 and be fixed with impeller 77.Therefore, screw 76 is the one rotation with impeller 77, is disposed in clamping under the state of two sliding bearing 92a, 92b at two ends, and rotation is bearing on the straight line running shaft 90 freely.

On the other hand, centrifugal pump 74 mainly comprises: with when the discharge tube 12b of fluid passage 12 is communicated with and become the centrifugal pump chamber 79 of the part of vertical tube part 72a; Rotation is contained in the impeller 77 in the centrifugal pump chamber 79 freely.As mentioned above, the internal diameter T2 of centrifugal pump chamber 79 " with the internal diameter T1 of spiral pump chamber 78 " is identical, and forms the internal diameter T3 of part greater than protuberance 91a ".

As mentioned above, at a distolateral magnet housing 82 that the drive magnet 84 with the rotation of the motor output shaft 75d one of motor 75 is held that is fixed with of this centrifugal pump chamber 79, by rotation drive magnet 84, impeller 77 just rotates along with drive magnet 84.Thus, screw 76 is just rotated with impeller 77 one.

In addition, on the inwall of centrifugal pump chamber 79, be formed with the discharge oral area 74a that is communicated with usefulness with the discharge tube 12b of fluid passage 12.Therefore, the liquid that sucks in the vertical tube part 72a is discharged to discharge portion 11 sides from discharging oral area 74a because of the attraction force of volute pump 73 and centrifugal pump 74.On the other hand, when driving volute pump 73 and centrifugal pump 74 to opposite direction, the liquid in discharge tube 12b and the 12c of water level displaying tube portion flows back in the vertical tube part 72a by discharging oral area 74a.And impeller 77 has and the above-mentioned the 1st and the 2nd same structure of example, makes motor output shaft 75d when rotation when drive motor 75, produces magnetic induction and be rotated in centrifugal pump chamber 79 on drive magnet 84.And, when impeller 77 rotations, both can make the liquid in rotation in the centrifugal pump chamber 79, can in vertical tube part 72a, produce the power that attracts air or liquid etc. again.

In addition,, be not limited to these, without departing from the spirit and scope of the present invention, can do various distortion though each above-mentioned example is respectively the example of preferable example of the present invention.For example, each above-mentioned small pump device 1,41,71 is respectively the structure in the electric hot water bottle 2 of packing into, but also can employing in other liquid discharge device, for example water heater, water purifier etc.And small pump device 1 of the present invention is owing to being with screw 16 liquid to be supplied in the rotating center of impeller 17 and to have the structure that prevents cavitation, so be suitable for the such liquid discharge device of liquid assimilating after the boiling.

In addition, as mentioned above, each screw the 16,46, the 76th is made of the single-screw of 8.43 ° of angle of lead, but also can sets angle of lead arbitrarily in 5～15 ° scope.In case in this scope, set, then can prevent air pocket and can improve pump efficiency.The entire axial length of spire is 27mm, but as long as 25mm is above just passable.So long as more than the 25mm, just can prevent air pocket reliably, the discharge capacity after guaranteeing to seethe with excitement.Each above-mentioned small pump device the 1,41, the 71st with the type of volute pump and centrifugal pump and usefulness, when screw is set as such structure, can be guaranteed the pump efficiency of volute pump.Therefore,, remove the blade-section of impeller or impeller, also screw can be used with premium on currency mechanism separately though the pump efficiency of pump-unit more or less descends.On the other hand, as above-mentioned example, except centrifugal pump is set on top, the bottom is provided with volute pump, also this configuration can be reversed.

In addition, each above-mentioned example is, in order to make the major component of premium on currency mechanism compactly, and make volute pump 13,43,73 and centrifugal pump 14,44,74 are configured in locational structure near each other, but also they can be configured on the position separated from each other, with glass tube etc. midway part couple together.

The present invention is adopted in as above explanation, owing to make the internal diameter of vertical tube part not identical according to different parts, so When flowing backwards, the flowing easily by disjunction of the liquid in the vertical tube part is not subjected to the impact of centrifugal pump and can successfully makes Liquid flows backwards. Therefore, utilize the driving of pump and can reach the water tank that is communicated with vertical tube part to vertical tube part reliably Interior grade is cleaned, and in situation about being installed on the electric hot water bottle, can prevent reliably that the 1st glass of water from being simultaneously This phenomenon of warm water.

In addition, adopt the present invention, because the external diameter of impeller is less than the external diameter of screw, so when flowing backwards, Impeller is littler to the flow effect of liquid, becomes the structure that can flow backwards smoothly.

In addition, adopt the present invention, can bring into play higher pump capacity and be difficult to owing to make the shape of screw The structure of air pocket takes place, so in situation about being installed on the electric hot water bottle, more produce effect.

Claims (13)

1. small pump device, be provided with the introduction part that imports liquid, make discharge portion that the liquid that imports from this introduction part discharges from the position of described introduction part upside, described introduction part be connected with described discharge portion and at least a portion has the fluid passage of vertical tube part, coaxial setting is by the volute pump with screw and have 2 premium on currency mechanisms that the centrifugal pump of impeller constitutes in the vertical tube part of this fluid passage, it is characterized in that the internal diameter of described vertical tube part is different at different parts.

2. small pump device according to claim 1 is characterized in that, the internal diameter of the part of the described screw of covering of described vertical tube part is different from the internal diameter of part of the described impeller of covering of described vertical tube part.

3. small pump device according to claim 1 and 2 is characterized in that, the internal diameter of the part of the described screw of covering of described vertical tube part is greater than the internal diameter of the part of the described impeller of covering of described vertical tube part.

4. small pump device according to claim 1, it is characterized in that, the internal diameter of the part of the described screw of covering of described vertical tube part is identical with the internal diameter of the part of the described impeller of covering of described vertical tube part, and in the part of the described screw of covering of described vertical tube part with cover part between the part of described impeller and form the bump that central direction to described vertical tube part protrudes and the internal diameter of this part is dwindled.

5. according to claim 1,2,3 or 4 described small pump devices, it is characterized in that, install in the end of described vertical tube part and carry out the position retaining member that the position keeps rotating the axial region that supports described screw and described impeller freely.

6. small pump device according to claim 5 is characterized in that, described position retaining member is the cylinder element that embeds described vertical tube part inwall, and the many roots that protrude from inwall one side direction center one side of this cylinder element are set.

7. small pump device, the fluid passage that is provided with the introduction part that imports liquid, makes discharge portion that the liquid that imports from this introduction part discharges from the position of described introduction part upside, described introduction part is connected with described discharge portion, in the inner coaxial setting of this fluid passage by volute pump and have 2 premium on currency mechanisms that the centrifugal pump of impeller constitutes with screw, it is characterized in that the external diameter of described impeller is less than the external diameter of described screw.

8. small pump device according to claim 7 is characterized in that, the external diameter of described impeller be described screw external diameter 20～80%.

9. according to claim 7 or 8 described small pump devices, it is characterized in that, at least a portion of described fluid passage has vertical tube part, and be provided with described volute pump and described centrifugal pump at this vertical tube part, the internal diameter of the part of the described screw of covering of described vertical tube part is greater than the internal diameter of the part of the described impeller of covering of described vertical tube part.

10. small pump device, the fluid passage that is provided with the introduction part that imports liquid, makes discharge portion that the liquid that imports from this introduction part discharges from the position of described introduction part upside, described introduction part is connected with described discharge portion, in the inner premium on currency mechanism that constitutes by volute pump that is provided with of this fluid passage with screw, it is characterized in that described screw constitutes with the single-screw of 5～15 ° of angle of lead.

11. small pump device according to claim 10 is characterized in that, the angle of lead of described screw is more than 8 °.

12. small pump device, the fluid passage that is provided with the introduction part that imports liquid, makes discharge portion that the liquid that imports from this introduction part discharges from the position of described introduction part upside, described introduction part is connected with described discharge portion, in the inner premium on currency mechanism that constitutes by volute pump that is provided with of this fluid passage with screw, it is characterized in that the axial length of the spire of described screw is more than the 25mm.

13. electric hot water bottle, it is characterized in that, the described introduction part of each described small pump device in the claim 1 to 12 is arranged on the bottom of water storage tank, described fluid passage is arranged on the outside of described water storage tank, described volute pump is arranged near the bottom of described water storage tank.

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