ES2229574T3 - VOLUMETRIC PUMP. - Google Patents

Abstract

A VOLUMETRIC PUMP (1) IS DESCRIBED IN WHICH A PISTON (6) IS SITUATED TO MOVE AXIALLY IN A SEAT (3) FORMED IN A VALVE BODY (2); THE PISTON (6) THAT DEFINES INSIDE THE SEAT (3) A PUMP CHAMBER OF VARIABLE VOLUME (8) AND THE EXTREME AXIAL OF THE SEAT (3) ARE CONNECTED TO THE EXTERNAL ENVIRONMENT THROUGH A SUPPLY CONDUCT (4) AND A DUCT IN ADMISSION (5); THE VOLUMETRIC PUMP (1) ALSO INCLUDES AN INTAKE VALVE (13) AND A DISCHARGE VALVE (14) TO REGULATE REGULARLY THE INPUT AND OUTPUT FLUID SUPPLY FOR THE PUMP CHAMBER (8) AND A RETAINING SPRING IN OPPOSITION (10) TO MAINTAIN THE PISTON (6) IN THE REST POSITION WITH WHICH THE VOLUME OF THE PUMP CAMERA (8) IS REDUCED TO A MINIMUM AND FINALLY WHEN AN ELECTRIC CURRENT PASSES THROUGH THROUGH, A SUSPECTABLE COIL TO PRODUCE A MAGNETIC FIELD TO INDUCE AN AXIAL MOVEMENT OF THE PISTON (6) IN THE SEAT (3) TO OBTAIN AN INCREASE IN THE VOLUME OF THE PUMPING CAMERA (8); THE ADMISSION VALVE (13) IS PROVIDED INSIDE THE PUMPING CHAMBER (8).

Description

Volumetric pump

The present invention is related to a volumetric pump

In particular, the present invention is related to a volumetric pump designed to guarantee the lubricating oil circulation of an internal combustion engine of two times of known type, to whose usage data exposed to reference is made below without losing their generic nature

As we well know, in combustion engines internal two-stroke, the lubricating oil supply to the intake manifold of the engine and any other part of the engine requiring continuous lubrication is effectively achieved by volumetric pumps with gears and driven pistons by a motor shaft.

Normally, these pumps provide a power proportional to the motor rotation ratio and frequently they can adjust this power according to the adjustment of the gas control to the engine inlet, to maintain a  specific level the relationship between the lubricating oil sent to intake manifold of the engine and the air sucked through the admission distributor itself.

Unfortunately, oil pumps currently in use cannot meet the requirements related to the anti-pollution standards that will be presented shortly. With the in order to stay within the limits established by these standards, two-stroke internal combustion engines must guarantee a Lube oil consumption lower than the current one, which only can be achieved using oil pumps that allow a extremely precise adjustment of the lubricating oil that circulates through the motor. In current volumetric pumps, such control only would be achieved by reducing the tolerances of coupling of the various pistons of the pump; said reduction it would only be achieved through complex manufacturing processes that would imply a considerable increase in production costs final.

A possible solution to the problem of standards anti-pollution that will be presented could be the use of volumetric pumps with electromagnetic drive whose Manufacturing is currently so widespread.

With reference to US 3250219, said pumps generally consist of a valve body basically cylindrical and a piston of ferromagnetic material installed to be introduced axially inside a seat cylindrical formed in the valve body. The two axial ends of the cylindrical seat communicate with the atmosphere through two connecting ducts that extend inside the body valve coaxially with the longitudinal axis of the body of valve, while the two chambers of variable volume in the that the piston subdivides the cylindrical seat communicate through of an axial conduit formed in the piston body.

Volumetric drive pumps electromagnetic also consist of an antagonist spring located in the interior of one of the two cameras of variable volume in the that the piston subdivides the cylindrical seat, so that it remains minimized the volume of the chamber that does not occupy the dock, and a coil of electrical conduction material, which when the electric current through it can generate a magnetic field capable of opposing the strength of the antagonist spring and axially move the piston so that it maximizes the volume of the variable volume chamber that does not contain the spring. The aforementioned chamber defines the pump's pumping chamber volumetric

Volumetric drive pumps electromagnetic mentioned above finally carry a intake valve located along the formed axial duct in the piston body, and a feed valve located at length of the conduit that connects the pumping chamber, or the chamber of variable volume that does not contain the antagonist spring, directly with the atmosphere.

Unfortunately, the volumetric pumps of electromagnetic drive described above present the great disadvantage that its scope is not what extensive enough to justify its use in engines internal combustion of two times.

In particular, such pumps do not offer a discharge capacity high enough to meet the oil requirements of an internal combustion engine that works at high speeds, which is mainly due to the fact that the total weight of the piston is too large to be able to make axial movements that allow time capabilities compatible with those required by internal combustion engines two times.

In addition, in the volumetric pumps of electromagnetic drive described above (see US Patent 3,250,219), intake and supply valves they are usually made of flexible plastic material, not being able to guarantee, because of distortion, the constant volume of the pumping chamber in all the possibilities of using the pump.

In order to solve this disadvantage, CH-675312 and FR-2465903 shows us the use of an intake valve that does not carry the piston and is located inside the pumping chamber. In more detail, CH-675312 and FR-2465903 talk about an intake valve consisting of an axial movement plug inside the pumping chamber and an antagonist spring located inside the pumping chamber, with a first end that reaches lean against the plug and a second end that comes to rest against the wall of the valve body, so that it maintains the cap resting against the piston to adjust duct access of passage formed inside the piston.

However, the main drawback of this solution is the existence of an unwanted recoil of the liquid in the intake duct during axial movement of the piston, what which compromises the optimal filling of the pumping chamber at high speeds.

The present invention aims at present a volumetric pump with electromagnetic drive that can solve the aforementioned problems and ensure very precise control of oil capacity with all the possibilities of using an internal combustion engine, with relatively low production costs.

In accordance with the present invention, the design of a volumetric pump consists of a valve body and at minus an axial mounting piston that is inserted inside a seat formed inside the valve body, said one being seat in communication with the atmosphere through a duct feeding and an intake duct, and defining the aforementioned piston inside said seat at least one chamber of variable volume pumping; also comprising the volumetric pump of a flexible system with capacity to maintain the aforementioned piston in the resting position where the volume is minimized of said pumping chamber, a coil of conduction material electrical which, when activated, can create a magnetic field, which allows the axial movement of the piston inside said seat, varying the volume of said pumping chamber, and being able to regulate at least one intake valve and one respectively discharges the flow of the inlet and outlet fluid from the aforementioned seat; said valve being located admission inside the pumping chamber, which does not carry the piston; the said volumetric pump being characterized because, at along said intake duct, also contains a disk with a calibrated central hole.

We will now describe the present invention referring to the attached drawings, which represent a non-restrictive operational example thereof, in which:

Fig. 1 is a sectional view of a pump volumetric designed in accordance with the terms of this invention;

Figures 2 and 3 are sectional views of a series of volumetric pump variants that we see in Figure one.

With reference to Figure 1, the number of reference 1 indicates the set of a volumetric pump that is will use, preferably but not necessarily, to circulate the lubricating oil in a two internal combustion engine time.

Volumetric pump 1 consists of a body of basically cylindrical valve 2, which extends so coaxial with a longitudinal axis A, and internally has a seat 3 that extends, preferably but not necessarily, so coaxial with axis A, and a pair of conduits 4 and 5 that can put in communication the two axial ends of the seat 3 with the atmosphere. The volumetric pump 1 also comprises a piston 6 of ferromagnetic material that is located with axial mobility inside of the seat 3 formed in the valve body 2, and defined in the inside the seat itself a pumping chamber 8 of variable volume Obviously, the connection between piston 6 and the Seat 3 has a liquid-proof seal.

Duct 4 communicates directly with the camera 8 and defines the feeding duct of the volumetric pump 1, while the duct 5 communicates with the seat 3 of the part opposite of chamber 8 in relation to piston 6, and defines the intake duct of the volumetric pump 1.

In the example we show here, conduits 4 and 5 in particular extend coaxially with the A axis that works opposite seat 3, so that each end corresponds to the respective end of the valve body 2. Said ends are designed so that they can be attached to the pipe through which the lubricating oil circulates.

However, the piston 6 has an orifice of step 9, which extends coaxially with the A axis to everything length of the piston 6 proper, with a view to guaranteeing the chamber 8 communication with duct 5.

Finally, volumetric pump 1 consists of a retaining spring 10 that can hold piston 6 in position at rest, in which the piston 6 minimizes the volume of the chamber 8, and a coil 11 of electrical conduction material located coaxially with the A axis, outside the body of valve 2. When activated with electricity, said coil 11 it can generate a magnetic field that is located in the body of the valve 2, so that the magnetic field produced causes a axial movement of the piston 6 that moves it from the position of rest, thus increasing chamber volume 8. Obviously, the aforementioned displacement takes place with the action of the spring 10.

In the illustrated example, in particular the seat 3 is subdivided into two portions 3a and 3b of different diameter, the piston 6 being mounted to enter the portion 3a of larger diameter, while chamber 8 consists of part 3b of the seat 3 and, as explained more clearly below, part of portion 3a when it reaches its maximum volume. For other part, the spring (70) is coaxially positioned with the A axis within portion 3a of the part opposite chamber 8 in relationship with piston 6 and has a first end that rests against piston 6 and a second end that rests against the lower part of seat 3, to keep piston 6 supported against flange 7 that connects portions 3a and 3b with each other from seat 3, or in the rest position.

Where the axial end of seat 3 joins in that the spring 10 is supported, or where the entrance to the duct 5 is attached, the volumetric pump 1 also has a disc 12 with a hole calibrated center, coaxially located with the A axis so that the calibrated hole is aligned with conduit 5.

Volumetric pump 1 also includes a intake valve 13 with capacity to regulate the access of the lubricating oil inside chamber 8, and a valve discharge 14 with capacity to regulate the oil outlet lubricant from the chamber 8. The intake valve 13 is located inside the chamber 8, to match the hole of step 9 of the piston 6, while the discharge valve 14 is located in conduit 4 immediately below the chamber 8.

In the example we see here, in particular the valve 13 has a plug 15 coaxially located in the inside the chamber 8, and an antagonist spring 16 located in the inside the chamber 8 coaxially with the A axis, with a first end that rests against the cap 15 and a second end which rests against the wall of the valve body 2, to maintain the cap 15 supported on the piston 6 thus preventing access from the hole 9 with a sealing system by fluids

On the contrary, valve 14 consists of a axially located plug 17 that is inserted into the conduit 4, and an antagonist spring 18 located inside the conduit 4 of coaxial shape with the A axis, with a first end that rests against the cap 17 and a second end that rests against a annular flange 19 located inside the duct 5, for keep the cap 17 supported against a contraction 20 located at the duct inlet 5.

In the example we see here, both the cap 15 as the 17 consist of a metallic spherical body.

Finally, volumetric pump 1, preferable although not necessarily, it carries a filtering component 21 installed inside the duct 5.

Referring to Figure 1, in order to facilitate the assembly of the volumetric pump 1, the body of valve 2 consists of three cylindrical portions, respectively referenced as 2a, 2b, 2c, in line with the A axis, and forming integral part of each other by an outer envelope 22 which extends coaxially to the A axis to protect the coil 11. In this case, the duct 5 is reached within the portion cylindrical 2a, the seat 3, inside the cylindrical portion 2b, while the conduit 4, inside the cylindrical portion 2c.

Obviously other solutions are possible structural to facilitate the assembly of the tubular body 2.

Next we will describe the operation of the volumetric pump 1, assuming that the pump is located at length of a lubricating oil circulation line.

While in service, when activated with electricity coil 11, the magnetic field it produces causes the axial displacement of the piston 6 and the consequent increase of camera volume 8.

During the movement of the piston 6, the spring antagonist 16 fails to keep the cap 15 leaning against the piston 6, which is due to the inertia of the cap 15 or the oil discharge lubricant that precipitates through the through hole (9). The lubricating oil that occupies the portion 3 a of the seat 3 together with the piston 6 it will discharge more easily through the hole of step (9) formed in the piston 6 which through the calibrated orifice of the disc 12, which is also easier because of depression produced inside chamber 8 due to the rapid increase of volume.

In view of displacement and volumes involved, when the antagonist spring 16 displaces the cap 15 to close the entrance to the passage hole 9 of the piston 6, chamber 8 has already been completely filled with lubricating oil that, in addition to the portion 3b of the seat 3, it now consists of part of the portion 3a of seat 3 proper.

When the magnetic field ceases, which is when it doesn't more electricity passes to coil 11, retaining spring 10 causes the piston 6 to return to the rest position, reducing quickly the volume of the camera 8. However, since the Lube oil can not be compressed, excess oil lubricant exits chamber 8 through conduit 4, displacing thus the cap 17.

Once the excess oil has been discharged lubricant, the antagonist spring 18 guarantees the return of the plug 17 until it leans against the gas control 20 that occurs in the duct entry point 5.

It is obvious that the capacity of the pump volumetric 1 is a function of the frequency with which the piston 6 moves inside the seat 3, that is, from the frequency with which the electric current is passed through of the coil 11.

According to a variant that we don't see here, the Piston 6 is made of permanent magnetic material.

In accordance with the variant we see in the Figure 2, the piston 6 is double acting and defines inside its seat two variable volume 9 pumping chambers that complement. Each of the cameras is connected to the atmosphere through a feed duct 4 that extends coaxially with the A axis, and has an intake valve 13 and a discharge valve 14, while the intake duct 5 it is in common communication with both cameras 9, and extends in the inside the valve body 2 perpendicular to the A axis, along of an appendix of the valve body 2, which in turn extends perpendicular to axis A. In this case, conduit 5 faces a branch 9 a of the passage hole 9 extending through the piston perpendicular to axis A, and disc 12 is located along the duct, immediately up from seat 3.

According to the variant we see in the Figure 3, the valve body 2 has two seats 3, each of the which will be driven by a respective piston 6, which define a pumping chamber 8. Similar to the previous variant, each one of the cameras 8 is connected to the atmosphere by means of a feed conduit 4 that extends coaxially to the shaft A, and carries its own intake valve 13 and its own valve discharge 14. In this case, the intake duct 5 communicates with both seats 3, and a terminal portion thereof extends in the valve body 2 coaxially to the A axis, along an appendix of the valve body 2 which extends in turn perpendicular to the A axis.

The advantages of the volumetric pump previously described are evident: the presence of disk 12 with the central calibrated hole along the intake duct 5 prevents the withdrawal of liquid in the intake duct 5 during axial movement of piston 6, resulting in a filling Optimum pumping chamber 8 at high speed.

Another advantage comes from the fact of disability deformation of the plug 15 of the valve 13, so that the chamber volume 8 is constant in any situation of functioning. Thus, the volumetric pump 1 can become a measuring device always trained to provide the same volume of oil under pressure on each pulse of electric current.

Other advantages of the volumetric pump 1 are its extremely simple construction, with a limited number of component parts in relative motion, and the fact that it can be governed directly from an electronic central unit that, by varying the frequency of feeding to coil 11, it is possible control in real time and with extreme precision the capacity as well supplied

Finally, it is obvious that they can be done modifications and variations in volumetric pump 1 here described and illustrated without exceeding the scope of the present invention

Claims (14)

1. A volumetric pump (1) consisting of a valve body (2) and at least one axially mounted piston (6) that is inserted into a seat (3) formed within the valve body (2) , said seat (3) being in communication with the atmosphere by means of a feed duct (4) and an intake duct (5), and said piston (6) defining inside said seat (3) at least one variable volume pumping chamber (8), also comprising the volumetric pump (1) of a flexible system (10) capable of keeping said piston (6) in the rest position in which the volume of said pumping chamber (8), a coil (11) of electrical conduction material that, when activated, can create a magnetic field, which results in the axial movement of the piston (6) inside said seat (3 ), varying the volume of said pumping chamber (8), and at least one intake valve (13) and a discharge valve (14) respectively with which the flow of the inlet and outlet fluid can be regulated from said seat (3), said intake valve (13) being located inside the pumping chamber (8) which does not carry the piston (6); characterized said volumetric pump (1) that, along the said intake duct (5), there is also a disc (12) with a central bore. 2. A volumetric pump according to claim 1, characterized in that said feed duct (4) directly connects said pumping chamber (8) with the atmosphere, said piston (6) carrying a passage duct (9) which guarantees the communication of the pumping chamber (8) with said intake duct (5). 3. A volumetric pump according to claim 2, characterized in that said piston (6) subdivides the seat (3) inside the valve body (2) into two portions that are respectively connected to the atmosphere by the feed duct (4) and the intake duct (5), the passage duct (9) of the piston (6) being able to connect the two portions of said seat (3) together. 4. A volumetric pump according to claim 3, characterized in that said feed ducts (4) and intake duct (5) connect the two coaxial ends of the seat (3) formed inside the interior with the atmosphere cited valve body. 5. A volumetric pump according to any one of claims 2 to 4, characterized in that said inlet valve (13) consists of a plug (15) that moves axially inside the chamber of pumping (8) and an antagonist spring (16) located inside the pumping chamber (8) with a first end that comes to rest against the plug (15) and a second end that comes to rest against the body wall valve (2), to keep the cap (15) resting against the piston (6) so that it fits while keeping the passageway (9) fitted in tight conditions by means of a liquid at the entrance of the passageway ( 9) inside said piston (6). 6. A volumetric pump, according to any of the preceding claims, characterized in that said supply line (4) immediately lowers an air throttle system (20) from said pumping chamber (8). ), and said discharge valve (14) consists of a movable plug (17) inside said feed duct (4), and an antagonist spring (18) with capacity to keep said stopper (17) resting against the said air throttle system (20), adjusting it in airtight conditions by means of a liquid. A volumetric pump, according to any of the preceding claims, characterized in that said disk (12) is located along said intake duct (5), to present its calibrated orifice coaxial with the axis (A ) of the duct. A volumetric pump, according to any of the preceding claims, characterized in that it consists of a filtering component (21) located along said intake duct (5). 9. A volumetric pump, according to any of the preceding claims, characterized in that said seat (3), said feed duct (4), said piston (6) and said passage hole (9) They extend coaxially with the same longitudinal axis (A). 10. A volumetric pump according to claim 9, characterized in that said valve body (2) has a basically cylindrical shape and extends coaxially with said longitudinal axis (A). 11. A volumetric pump, according to any of the preceding claims, characterized in that said piston (6) defines inside the said seat (3) two variable volume pumping chambers (9) that complement each other, being said pumping chambers (8) directly connected to a respective feed duct (4), and communicating with the same intake duct (5) through a through hole (9) formed in said piston (6) . 12. A volumetric pump according to one or the other of claims 1 to 10, characterized in that it consists of two pistons (6) installed axially, each of which is inserted into its respective seat (3) formed in said valve body (2); the pistons (6) define the respective pumping chambers (8) of variable volume within the corresponding seats (3). 13. A pump according to any of the preceding claims, characterized in that said piston (6) is made of ferromagnetic material. 14. A pump according to any one of claims 1 to 12, characterized in that said piston (6) is of permanent magnetic material.