CN1361358A

CN1361358A - Roulette pump

Info

Publication number: CN1361358A
Application number: CN 01144019
Authority: CN
Inventors: 小杉民男
Original assignee: Mitsuba Electric Manufacturing Co Ltd
Current assignee: Mitsuba Corp
Priority date: 2000-12-25
Filing date: 2001-12-25
Publication date: 2002-07-31
Also published as: TW508412B; EP1219835A2; EP1219835A3; JP2002195168A

Abstract

The object of the invention is to construct a trochoid pump to suppress generation of a vapor lock phenomenon based on a rise in the fuel temperature without loss of pump efficiency. The construct of the trochoid pump is that, namely, a deaerating hole H that communicates with the outside is formed on the groove bottom face 10e of the rotor casing in which a trochoid gear T is accommodated. The deaerating hole H is defined at a position that is closed by the front side edge of either one of inner and outer teeth 12a, 13a of inner and outer rotors 12, 13 in the direction of rotation. The inner and outer rotors arranged at the front side in the direction of rotation forms any one of the pump spaces PR that the trochoid gear T forms and enters in the maximum capacity state. When the optionally pump space PR volume is being reduced, vaporized fuel is exhausted.

Description

Roulette pump

TECHNICAL FIELD OF THE INVENTION

The present invention relates to the roulette pump in a kind of vehicle etc.

Prior art

In general, known roulette pump is as the petrolift that starts the pusher side fueling to vehicle.In above-mentioned roulette pump, has a kind of like this structure, it is that it comprises: a cycloid gear, wherein, the external tooth number of teeth of internal rotor is different with the internal tooth number of teeth of external rotor, the external tooth of this internal rotor and the tooth of external rotor mesh, and rotate with the rotation of internal rotor by external rotor, and the pump chamber volume that forms between the tooth of two rotors changes gradually; And a rotor housing, an end face of this cycloid gear rotatably is resisted against on this rotor housing.This rotor housing has: an inlet hole, this inlet hole are formed at and face pump chamber volume and increase gradually on half part with the side that produces decompression state; One tap hole, this tap hole are formed at and face pump chamber volume and reduce gradually on second half part with the side that produces pressurized state.And fuel sucks by inlet hole along with the increase gradually of the rotation of two rotors and pump chamber volume, and discharges by tap hole with the minimizing gradually of pump chamber volume, like this, as mentioned above, can realize pumping action.

On the other hand, although each pump chamber is full of fuel, when fuel temperature raise along with the continuous firing of pump, the low boiling point component evaporation in the fuel will produce air pocket.When this air pocket produces, the volume reducing of liquid fuel in the pump chamber, this problem causes that fuel flow rate reduces, and then makes the discharge capacity vanishing, that is to say, the steam binding phenomenon occurs.Therefore, usually as shown in Figure 7, a kind of such structure has been proposed, therein promptly: the cycloid gear T that is made of internal rotor 17 and external rotor 18 can rotate in the Baltimore groove part 16 of rotor housing, contact at a end face with cycloid gear T, on the bottom surface 16a of the Baltimore groove part 16 of this rotor housing, be formed with one and be similar to through hole, be arranged in half above-mentioned part and suck part 16b with the long curve hole shape of external communications, with one be similar to Baltimore groove, be positioned at second half part and the long curve hole shape tap hole 16c of the guiding channel that is communicated with the opening side of rotor housing 16 is arranged, wherein, with the concave bottom that pore 16d is formed at tap hole 16c of removing of external communications, degasification removes pore 16d by this and carries out.And, in this structure, utilize volume along with pump chamber PR to reduce gradually and the high pressure-charging that produced among the pump chamber PR between wheel tooth 17a, the 18a of each rotor 17 and 18, will force the fuel of evaporation to be discharged by removing pore 16d.

Summary of the invention

Goal of the invention

Therefore, because the above-mentioned pore 16d of removing of the prior art is formed at the groove bottom of the tap hole 16c that forms facing to the high pressure side, even so fuel has normal temperature and is under the normal use condition that does not produce air pocket, fuel also is forced through the discharge except that pore 16d.Therefore, this pump performance can be equivalent to the amount of above-mentioned discharge fuel and worsen.At this moment, in order to guarantee required discharge volume, this roulette pump will be with higher power work, and this has just produced the problem that needs big power consumption or large scale pump.The invention solves this problem.

And, because remove pore 16d, so the diameter that removes pore 16d has very big influence to the efficient of pump in the high pressure side.Under these circumstances, another problem of generation is, if the diameter inaccuracy in this hole, pump performance can be unstable so, makes the reliability of products variation.These problems and other problem can solve by the present invention.

Realize the device of purpose

The present invention is used for solving these and other problem of above-mentioned situation.Roulette pump of the present invention comprises: a cycloid gear, wherein, the described internal tooth engagement of internal rotor external tooth that the number of teeth is different with the internal tooth number of teeth of external rotor and described external rotor, and change gradually with the volume that the rotation of internal rotor is rotated in the pump chamber that forms between the described tooth of two rotors by external rotor; And a rotor housing, an end face of described cycloid gear rotatably is resisted against on this rotor housing, this rotor housing has: an inlet hole, this inlet hole be formed at face that described pump chamber volume increases gradually half part of a side on; And a tap hole, this tap hole is formed on second half part that faces the side that described pump chamber volume reduces gradually; Wherein, when formation in described rotor housing is discharged except that pore so that with the evaporated fuel in the described pump chamber, the described rear side that is positioned at described tap hole except that pore along the rotor rotation direction, and be formed at such position, promptly, maximum and when beginning to reduce its volume when the volume of described pump chamber, the described pore that removes can be communicated with pump chamber.

This structure has been arranged, owing to the fuel that high temperature evaporates can be discharged expeditiously.

In this structure, when pump chamber arrived its maximum volume, the above-mentioned inlet hole that forms on half part of above-mentioned rotor housing can interrupt and being communicated with of above-mentioned pump chamber.

And, in this structure, the above-mentioned outside diameter office that can be positioned at and be formed at described internal rotor except that pore.

Brief description of drawings

Fig. 1 is that side view cuts open in the office of roulette pump;

Fig. 2 (A) is the front view of Fig. 1, and Fig. 2 (B) is the rear view of Fig. 1;

Fig. 3 (A) is the rear view of rotor housing, and Fig. 3 (B) is the cross-sectional figure along the line X-X among Fig. 3 (A);

Fig. 4 (A) is the front view of cycloid gear, and Fig. 4 (B) is the cross-sectional figure along the line X-X among Fig. 4 (A);

Fig. 5 (A), (B) and (C) be the view that explanation removes the relation between the state that gaseous core and pump change along with the rotation of cycloid gear;

Fig. 6 is a plotted curve, shows with respect to the relation roulette pump of the roulette pump of prior art and present embodiment, between fuel temperature and the discharge capacity; And

Fig. 7 is the view that removes gaseous core in the cycloid gear of explanation prior art.

Inventive embodiment

1 to 5 introduce embodiments of the invention below with reference to the accompanying drawings.

In the accompanying drawing, roulette pump 1 is set in fuel tank as petrolift.Motor part M and the pump part P that is arranged in another side place of this motor part M are installed in the inside of cylinder blanket 2, and this has constituted roulette pump 1.The motor drive shaft 3 that constitutes said motor part M is arranged to shell 2 coaxial, and an end of this motor drive shaft 3 can be rotated to support on the lid 4 of an above-mentioned side opening that is positioned at shell 2, and this lid 4 is fixed to cover the opening of this side.The other end of motor drive shaft 3 is by rotatably mounted like this, and promptly it can pass the through hole 5a that is fixed on the dividing plate 5, and this dividing plate 5 non-rotatably is positioned on the inner circumferential surface of shell 2, and motor part M and pump part P are separated.The other end of this motor drive shaft 3 protrudes towards pump chamber P one side.The armature core 6 that is wound with coil is arranged to one with motor drive shaft 3, and plate-like rectifier 7 is fixedly mounted on armature core 6 those sides of motor drive shaft 3.A plurality of rectifier element 7a are fixedly mounted on the side of rectifier 7.Be arranged to can along the direction of motor drive shaft 3 protrude and the protrusion tip of the brush 8 regained be configured to above-mentioned lid 4 elasticity sliding motion contact.And, on this lid 4, be provided with the sub-8a of bringing-out that is used for to brush 8 power supply, and the back with the fuel tap hole 4a that introduces can with external communications.And the permanent magnet 9 that forms magnetic field is fixedly mounted on the inner circumferential surface of shell 2, and wherein, motor drive shaft 3 is provided with like this, that is, and and can be along with rotating integratedly with this armature core 6 to the power supply of rectifier 7 by brush 8.

The rotor housing 10 that constitutes said pump part P plays the lid effect that covers at the opening at another side place of shell 2, wherein, plate-like outer peripheral edge portion 10a is installed in by inside on the opening at another side place of shell 2, and by carrying out joint filling in the mounting point, inside of this shell 2 with this outer peripheral edge portion 10a fixing seal on shell 2.Plate-like Baltimore groove part 10b is formed on the inboard (side) of above-mentioned rotor housing 10.The groove center G of this respective concave slot part 10b is formed under the state of the center of circle R that departs from rotor housing 10.And cam ring 11 is fixed into one with the end face of the groove of above-mentioned Baltimore groove part 10b, thereby inside is installed in the there, and cycloid gear T rotatably is contained on the inner circumference of cam ring 11.Bearing part 10d is shaped like this, promptly, with the concentric state of the center of circle R of rotor housing 10 under, the other end place at the groove bottom 10c of above-mentioned Baltimore groove part 10b is recessed, axially be bearing in this bearing part 10d from dividing plate 5 the other end, so that against this supporting portion 10d to the motor drive shaft 3 of the side protrusion of pump part P.

And, long curve hole shape inlet hole 10e is positioned at the right half part (corresponding to half part of the present invention) of center line M, the central lines of this center line M and Fig. 3 rotor housing 10 and Baltimore groove part 10b, and this inlet hole 10e is formed at the groove bottom 10c place of the above-mentioned Baltimore groove part of rotor housing 10.Inlet hole 10e is shaped like this, and promptly the same through hole of its shape is slotted on groove bottom 10c, and makes the inside and outside of rotor housing 10 communicate with each other, and the fuel in the fuel tank is configured to the internal communication by inlet hole 10e and roulette pump 1.

In addition, the tap hole 10f that recessed one-tenth is similar to long curved hole is formed on this groove bottom 10c, and is positioned at the left-half (corresponding to second half part of the present invention) of above-mentioned center line M.Leading to the guiding channel 10g of outer diameter face of cam ring 11 and the outer diameter face of tap hole 10f is integral recessed.Funnel shape fuel guide body 10h is formed in the outer surface of inlet hole 10e (other end), thereby protrudes from this inlet hole, so that guide fuel into rotor housing inlet hole 10e.

On the other hand, a plurality of external tooth 12a are formed on the periphery of internal rotor 12, and this internal rotor is the constituent element of cycloid gear T, in the present embodiment, upwards are formed with six teeth week.And, internal rotor 12 is loaded under such state in the Baltimore groove part 10b, promptly, another side of this internal rotor 12 rotatably contacts with the groove bottom 10c of rotor housing, and the other end of the motor drive shaft 3 that protrudes to pump part P one side is fixed on rotating center (being similar to the key of the keyhole of packing into), and like this, it can prevent to rotate, wherein, this internal rotor 12 is configured to be integral and rotation with one heart with the motor drive shaft 3 of the center of circle R of center surrounding rotor housing 10.In addition, a plurality of internal tooth 13a were formed on the interior week of external rotor 13, in the present embodiment, and along circumferentially being formed with seven teeth.And, under such state external rotor 13 being arranged to inside is installed among the Baltimore groove part 10b, promptly, another side of this external rotor 13 rotatably contacts with this groove bottom 10c, thereby this external rotor 13 is arranged to center ring around the groove center G of Baltimore groove part 10b rotation, and this Baltimore groove part 10b is eccentric in motor drive shaft 3 (internal rotor 12).The external tooth 12a of internal rotor 12 and the internal tooth 13a of external rotor 13 are engaged with each other in lower half portion of Fig. 3 and Fig. 4 (A), thereby when internal rotor 12 rotations, make external rotor 13 with these internal rotor 12 rotations.

And, a sealing plate 14 that contacts with the excircle of external rotor 13 is disposed in the side place of inner and outer rotors 12 and 13 (cycloid gear T), the sealing plate is loaded in the Baltimore groove part 10b, thereby by being arranged in spring 15 between sealing plate 14 and the dividing plate 5 against a side of this Baltimore groove, cycloid gear T is pressed towards the groove bottom 10c of rotor housing 10.Therefore, the edge circumferentially is formed with six both sides by the pump chamber PR of the bottom land of rotor housing surface 10c and sealing plate 14 sealings between interior

external tooth

12a and 13a, and each pump chamber PR is provided with like this, be that they rotate and motion with respect to both sides with the rotation of cycloid gear T, change its volume simultaneously gradually.

That is to say that these pump chambers PR is configured to its volume to be changed like this, promptly when any one pump chamber PR was positioned at the bottom position of Fig. 4 (A), the volume of this pump chamber was roughly zero (minimum volume state), and when it is positioned at apical position, its volume maximum.And, in the present embodiment, cycloid gear T is provided in rotation in the counterclockwise direction among Fig. 4 (A), thereby, the right half part of Baltimore groove part 10b (in the face of the accompanying drawing direction) is a reduced-pressure zone, and at this moment the volume of pump chamber PR increases gradually along with the rotation of cycloid gear T, makes in the time of this cycloid gear rotation that the fuel in the fuel tank passes through inlet hole 10e inflow each pump chamber PR facing to described zone, thereby the fuel capacity of pump chamber PR increases gradually.Otherwise, the left-half of Baltimore groove part 10b (in the face of the accompanying drawing direction) is an anallobar, at this moment the volume of pump chamber PR reduces gradually along with the rotation of cycloid gear T, thereby, in this cycloid gear rotation, each pump chamber PR discharges fuel by tap hole 10f, and the fuel capacity of pump chamber PR reduces gradually.Like this, the fuel of discharging from pump chamber PR is guided the outer diameter face of a side (dividing plate 5 those sides) of rotor housing 10 into by the guiding channel 10g that is communicated with discharge section 10f, and by opening 5b inflow motor part M side on the discoid plate that is fixed on dividing plate 4, that be similar to through hole.Then, the fuel that flows into motor part M side by with lid form one fuel tap hole 4a and from roulette pump 1 row to or supply engine.

Below with reference to Fig. 5 (A) position of inner and

outer rotors

12 and 13 is described and form above-mentioned inlet hole 10e and the position of tap hole 10f between relation.Fig. 5 (A) has represented the maximum volume state, and at this moment, any one pump chamber PR is positioned at head portion, and the volume of pump chamber PR reaches maximum.Under this state, illustrate and be based on such hypothesis, that is, the pump chamber that is under the maximum volume state is the first pump chamber PR1, pump chamber subsequently along sense of rotation be second, third, the 4th, the 5th, the 6th and the 7th pump chamber PR2, PR3, PR4, PR5, PR6 and PR7.Under this maximum volume state, inlet hole 10e is facing to the 5th and the 6th pump chamber PR, and form such size, promptly not facing to the first and the 4th pump chamber PR, this inlet hole 10e is extending between the 6th pump chamber PR6 and the first pump chamber PR1 along the tip edge part on the direction of two

rotors

12 and 13 rotations, and be configured to like this, promptly it is opened to always pump chamber PR is reached till the maximum volume.Therefore, when the volume of selected pump chamber PR reaches maximum, inlet hole 10e enter make this inlet hole 10e interrupt with selected pump chamber PR between the state that is communicated with, and the inside of the first pump chamber PR1 does not enter decompression state.

On the other hand, tap hole 10f is facing to second, third and the 4th pump chamber PR2, PR3 and PR4.And, tap hole 10f partly forms such size along the posterior edges of sense of rotation, it is its core that arrives the second pump chamber PR2, thereby, volume is that peaked selected pump chamber PR is provided with like this, that is, through beginning to reduce volume up to the scheduled time of this pump chamber facing to tap hole 10f in arrival facing to pump chamber PR before the position of the second pump chamber PR2, this pump chamber PR is communicated with tap hole 10f.

Remove pore H and be formed on the groove bottom 10c of rotor housing 10, lead to the outside thereby pass this bottom surface 10c.And, should remove pore and be positioned at such position, that is, it by along sense of rotation, inner and

outer rotors

12 and 13 any one in the posterior edges sealing of

external tooth

12a and 13a, thereby constitute the first pump chamber PR1 under the above-mentioned maximum volume state.Although it is little to remove the diameter of pore H, it is opened when cycloid gear T turns over above-mentioned maximum volume state a little.That is to say that it is provided with like this, that is, (see Fig. 5 (B)) when the selected pump chamber PR under being in the maximum volume state begins to reduce its volume, should remove pore H can be communicated with selected pump chamber PR.

Like this, in the present embodiment, remove pore H and be formed at upward such position of groove bottom 10c, seal near the contact segment that is it by the crown of the crown of internal tooth 13a and external tooth 12a, thereby constitute the pump chamber PR that is under the maximum volume state, specifically, this position is roughly corresponding to the outer diameter end of internal rotor external tooth 12a.And, remove pore H and be positioned at the rear side of tap hole 10f, and be formed under such state along sense of rotation, promptly removing between pore H and the tap hole 10f has predetermined interval.

Therefore, when the fuel of evaporation accumulated in pump chamber PR, the fuel of this evaporation was discharged from removing pore H.At this moment, because removing pore H is under the pressurized state that its volume reduces at pump chamber PR and is communicated with pump chamber PR, so discharge from this pump chamber PR under the state that the fuel of evaporation is exerted pressure to pump chamber PR attempting to reduce volume, wherein, the performance that evaporated fuel is discharged from tap hole H will strengthen.In addition, the pore H that removes of present embodiment is positioned at the rear side of tap hole 10f along sense of rotation, and this tap hole 10f is formed in the zone of high pressure of the left-half of groove bottom 10c, therefore, can arrange predetermined interval between them.Therefore, cycloid gear T rotates from above-mentioned maximum volume, and in its rotation, this pump chamber PR with also keep after tap hole H is communicated with one section only to make pump chamber PR and except that the scheduled time that is communicated with between the pore H.Then, pump chamber PR is communicated with (seeing Fig. 5 (C)) with tap hole 10f, wherein, is suppressed by the exhaust that removes pore H.Therefore, can guarantee preset time at interval, in this time lag, should remove pore H and realize its degassing function effectively, wherein, can guarantee that boil-off gas removes pore H from this and discharges.

By regulate removing pore H and tap hole 10f, can set above-mentioned preset time fully at interval along the distance between the posterior edges of sense of rotation.

In an embodiment of the present invention, its structure as mentioned above, by cycloid gear T along with the rotation of motor part M is rotated, the inlet hole 10e that roulette pump 1 makes the fuel in the fuel tank pass through rotor housing 10 flows into pump chamber PR, and make the fuel among the pump chamber PR pass through the opening 5b row of tap hole 10f and dividing plate 5 to motor part M, wherein, fuel is arranged to the outside by the fuel tap hole 4a on the lid 4 that is formed at roulette pump 1, thereby by this roulette pump 1 fueling.And, by this structure, when fuel when the continuous operation of roulette pump 1 is in high temperature and evaporates, the fuel of evaporation forms in each pump chamber PR.But, corresponding evaporated fuel is discharged by removing pore H, when reducing its volume after pump chamber PR tries reaching the maximum volume state, should remove pore H and will try to open.Therefore, because the exhaust of pump chamber PR is to carry out in the incipient stage that pump chamber PR tries to reduce the pressurizing area of its volume, so swept volume can increase.Therefore, can discharge evaporated fuel efficiently, thereby reduce the generation of air pocket.

In an embodiment of the present invention, inlet hole 10e reach the maximum volume state up to this selected pump chamber PR, thereby the inside that can prevent this pump chamber PR enters decompression state facing to selected pump chamber PR.Therefore, when attempting to reduce the volume of pump chamber PR, can not form situation about evaporated fuel can not be discharged owing to decompression state occurs in this pump chamber PR.

In addition, in this embodiment, at tap hole 10f with except that between the pore H predetermined interval is arranged, and pump chamber PR will keep the scheduled time with the state that continues to be communicated with except that assurance between the pore H.On the other hand, because as mentioned above, when the pump chamber that reaches maximum volume begins to reduce its volume, removing pore H will be communicated with pump chamber PR, therefore can not appear at and force the situation of carrying out degasification under the high pressure conditions, like this, when fuel temperature just often, can reduce from removing the fuel quantity that pore H discharges.Therefore, do not need further to increase power,, do not need further to improve the accuracy of removing pore simultaneously so that guarantee high pumping efficiency.Therefore, can low cost provide roulette pump highly reliably, and can make fuel loss reduce to minimum.

Fig. 6 shows the roulette pump that utilizes above-mentioned prior art and utilizes the result of above-mentioned first embodiment's roulette pump 1 with respect to corresponding fuel temperature measurement discharge capacity.According to this result, although can observe in two pumps: discharge capacity all reduces when temperature raises, and after temperature surpassed about 45 ℃, the reduced rate of roulette pump of the present invention was approximately half of reduced rate of the roulette pump of prior art.And, when temperature is approximately 60 ℃, because of fuel along with the rising of fuel temperature is evaporated, so discharge capacity also correspondingly reduces, wherein, can think that discharge capacity is not self to reduce according to roulette pump 1.

In addition, the present invention is not limited to the foregoing description.Remove pore and can be formed on such position arbitrarily, when promptly the pump chamber when being in the maximum volume state begins to reduce its volume, should remove pore and be communicated with this pump chamber.In Fig. 5 (A), remove pore can along sense of rotation be formed at last side place inner and outer rotors interior external tooth, along any position on the peripheral edge portion of the rear side of sense of rotation, thereby constitute the pump chamber that is in maximum volume.

The explanation of reference number

1 roulette pump

2 shells

3 motor drive shafts

5 dividing plates

10 rotor cases

10b Baltimore groove part

The 10c groove bottom

The 10e inlet hole

The 10f tap hole

11 cam rings

12 internal rotors

13 external rotors

14 sealing plates

M motor part

P pump part

T cycloid gear

Claims

1. roulette pump comprises:

A cycloid gear, wherein, the described internal tooth of internal rotor external tooth that the number of teeth is different with the internal tooth number of teeth of external rotor and described external rotor meshes, and rotates with the rotation of internal rotor by external rotor, and the volume of the pump chamber that forms between the described tooth of two rotors is changed gradually; And

A rotor housing, an end face of described cycloid gear rotatably is resisted against on this rotor housing, and this rotor housing has: an inlet hole, this inlet hole are formed on half part that faces the side that described pump chamber volume increases gradually; And a tap hole, this tap hole is formed on second half part that faces the side that described pump chamber volume reduces gradually;

It is characterized in that, when formation one on described rotor housing is discharged from described pump chamber except that pore so that with the fuel of evaporation, the described pore that removes is positioned at the rear side of described tap hole along the rotor rotation direction, and be formed at such position, promptly maximum and when beginning to reduce its volume when the volume of described pump chamber, the described pore that removes can be communicated with pump chamber.

2. roulette pump as claimed in claim 1 is characterized in that, when pump chamber arrived its maximum volume, the described inlet hole interruption that forms on half part of described rotor housing was communicated with described pump chamber.

3. roulette pump as claimed in claim 1 or 2 is characterized in that, the described outside diameter office that is positioned at and is formed at described internal rotor except that pore.