DE1212779B - Hydraulic speed controller for injection pumps of internal combustion engines - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

Int. α .:

F02d

German: 46b2-16

EDITORIAL

Number: 1212779

File number: B 522211 a / 46 b2

Filing date: February 24, 1959

Opened on: March 17, 1966

The invention relates to a hydraulic speed controller for injection pumps of internal combustion engines.

Such regulators are already known which have a pulsating pump which operates at one speed (or speed) is driven, which are formed as a function of the control factor Speed (or rotational speed) changes and the liquid delivers into a pressure accumulator, which is provided with a throttled outlet, so that the pressure prevailing in this memory in Depending on the speed of the pump is variable. This pressure is then used for control a control element of the fuel injection pump.

This scheme has the disadvantage that because of the pulsating delivery of the pump pulsating Pressure fluctuations arise in the pressure accumulator, which in turn have a detrimental effect on the pressure affect actuated control element in the memory.

According to the invention, this disadvantage is thereby eliminated avoided that in the connection between the memory and that to be adjusted by the memory pressure Control element switched on a closure element controlled in the work cycle of the pulsating pump is that the said connection interrupts in the periods during which the pulsating pump Conveying liquid in the memory, however, between releases the said connection for two consecutive funding periods.

According to an advantageous embodiment of the invention acts on the throttled outlet of the Pressure accumulator a control slide, which the free cross-section of this throttled outlet in the same direction changed with the drive speed of the pulsating pump.

In the event that the delivery of the fuel injection pump with each delivery stroke by release an outlet opening is stopped, so that there is still a remaining amount of fuel from this outlet opening exits, this remaining amount of fuel is expediently used to feed the pressure accumulator used.

The invention is explained below by way of example with reference to the drawings.

Fig. 1 shows a schematic sectional view of a speed controller according to the invention, the pulsating pump of which by a fuel injection pump is formed, the delivery rate of which is controlled by the controller;

Fig. 2 also shows a schematic sectional view of another embodiment of the object the fig. 1;

Hydraulic speed controller for
Injection pumps for internal combustion engines

Applicant:

Societe Anonyme pour! 'Exploitation
des Procedes Chimiques et Physiques,
Zug (Switzerland)

Representative:

Dr.-Ing. W. Lampert, patent attorney,

Stuttgart W, Breitscheidstr. 4th

Named as inventor:
Pierre Etienne Bessiere,
Neuilly-sur-Seine, Seine (France)

Claimed priority:

France of March 1, 1958 (759 474)

Fig. 3 shows another embodiment of a speed controller according to the invention, the pulsating Pump is formed by the transfer pump of the fuel injection pump, the delivery rate of which is regulated by the controller.

The controller has a pulsating or reciprocating pump, in particular a piston pump, which is driven at the speed or speed that forms the control factor or at a speed that can be varied from this first speed. During its delivery stroke, this pump conveys liquid into a channel 1, via devices explained below, which guides this liquid through a section 1 a into a reservoir 2 for storing the liquid under pressure. At the space for receiving the liquid in the memory, a relatively narrow outlet 3 is provided, which is designed so that the liquid in the memory 2 is under a certain pressure, which is greater, the greater the drive speed of the liquid in the storage pump is.

The pressure prevailing in the memory is used to adjust a z. B. formed by a slide 4 Member against a z. B. exploited return force exerted by a return spring 5, so that the adjustment of this link depends on the

609 538/113

3 4

speed of the pump and thus the control factor in. a Zylirider-14 under the influence of the in

forming speed depends. This member 4 the memory 2 against the prevailing pressure

can even be displaceable as a function of the speed of a return spring 13.

The element to be controlled may be one of the elements exerted by springs 5, 10 and 13

drive like link, which can then of course by the 5 return forces at will or

Rack of an injection pump, a valve flap, can be changed automatically. The location

a valve, a cock, an electrical counter- the support points of these return springs with the help

stand or the like. Can be formed. changed by adjusting screws 5 a, 10 a and 13 a

To prevent that from becoming dependent on.

the drive speed of the pulsating pump io The controller works as follows: During the adjustable member 4 of the controller due to the pul- time segment, during which the pulsating sintering delivery of the pump delivers strong vibrations pump liquid in the memory 2, the executes is in the the prevailing in the memory 2 closure member 6, the channel Ib closed, so that the pressure of the member 4 supplying channel Ib a of the slide 4 remains in its position. At the same time the closure member 6 is switched on, which is controlled in such a way that a certain amount of liquid is stored in the reservoir so that it stores the connection between the reservoir 2 rather 2, which presses the piston 9 of the reservoir and the member 4 to the right during the time periods breaks by the spring 10, in which the pulsating pump liquid is put under a certain pressure, although it delivers into the reservoir, so that the member 4 naturally exits a part of this liquid immediately through the outlet 3 at least approximately unaffected during these periods of time.

remains movable, while the closure member 6 the When the promotion of the pulsating pump in

Channel Ib opens during the time segments and the memory stops, the slide 6 opens the

In the memory 2 prevailing pressure on the member 4 channel Ib, and the pressure in the memory acts on

lets act during which the pulsating pump the member 4. During the period in which

does not deliver any liquid into the memory 2, while the pump 25 does not feed into the memory, shifts

which, however, the liquid through which of course the spring 10 moves the piston 9 to the left,

The pressure prevailing further through the out of which so a certain amount of the pressure is in the memory

let 3 be expelled. Pressurized liquid over storage tank

This closure member can drive out the outlet 3 in various ways. However, the greater the

Be designed and e.g. in the form of an operating speed of the pulsating pump,

Slide, which in a cylinder 7 repeats the faster the period of time,

is displaceable and a groove 8 or a not shown in which the pump conveys into the memory, and

presented transverse channel, which shifts the channel Ib the more the middle position of the

open when they are in alignment with him, but piston 9 in the memory 2 to the right, so that the

close it when the slide 6 is adjusted, 35 middle prevailing in the memory 2 and on the

that the groove or the continuous channel not acting member 4 pressure is also greater. This

coincide more with the channel Ib . Link 4 is also adjusted in its cylinder

This control of the slide 6 takes place preferably to the further to the right, the greater the speed either by means of a member 40 moving in synchronism with the speed of the pulsating pump, and this piston of the pulsating pump keeps the position due to the closure of the channel Ib . (Plunger etc.) or by part of the liquid displaced by the end of the time periods in which the pulsating piston of the pump is displaced. The pump delivers fresh liquid to the reservoir 2. Control of the slide 6 takes place in any case so that since the free cross section of the outlet 3 he closes the channel Xb during the delivery stroke (piston 12 controlling this cross section the more of the piston) of the pulsating pump and 45 opens the more the pressure in the memory 2 zuihn opens during the return of the piston. increases this pressure too rapidly

The memory 2 can be switched off in various ways, depending on the speed of the pump

are formed and z. B., as in Fig. 1 shown avoided. It can even have a regulating effect

have a piston 9, which is contrary to the fineness in a very large area

Force of a return spring 10 in a cylinder 11 50 of the drive speed of the pulsating pump

is displaceable, one of which is constant from the piston 9. It also highlights the differences between

bounded chamber forms the space in which the greatest and the smallest pressure in the

liquid reservoir 2 delivered by the pulsating pump during the time periods in which

is stored, while the spring 10 in the other - the pump does not deliver any liquid into the memory

ren chamber is housed. The memory can 55 and in which the closure member 6 the channel Ib

also be designed as a pneumatic accumulator, opens, significantly reduced by the fact that each pressure

as shown in FIG. would decrease in the memory 2 a reduction of the

To cause a too rapid increase in the pressure in the free cross section of the outlet 3.
Memory 2 with an increase in the drive speed. With the controller described, a speed of the pulsating pump is obtained. if the pulsating pump forming the control factor remains constant. When a speed increases, and vice versa. The preferred change in the drive speed, in pulsed fashion, is immediately that in the reservoir 2 in front of the pump, e.g. when there is an increase, the pressure prevailing at the outlet 3 increases used, which depending on its position, the _ piston 4 transmitted pressure also steadily increases the throttle point 3 more or less opens. This part too, until a new one, a new constant speed can e.g. B. have the shape of a piston, which speed corresponding value is reached.

As already stated, the pulsating pump is generally a piston pump educated. Any pump that forms the control factor with the can be used for this Speed or is driven at a speed proportional to this. It can z. B. the feed pump can be used, which is the pump chamber of the injection pump of this engine feeds, but the injection pump itself can also be used, especially the unused delivery capacity this pump, d. H. the delivery surplus of the same after the interruption of the injection. So z. B. in the on F i g. 1 device shown the funding surplus with a an injection pump provided with a pendulum body to feed the memory 2 of the controller.

The pump shown in Fig. 1 with a pendulum body, to which the controller described above is attached is, has a main piston 15 which works in a cylinder 16 and with a back and forth moving forward by any suitable means, e.g. B. by means of a not shown Cam, is driven at a speed that corresponds to the speed of the motor to which the pump is attached is proportional.

A transfer pump connected to the delivery side of a transfer pump (not shown) opens into the cylinder 16 Feed line 17, which is exposed by the piston 15 when this is at its lower Dead center is located (see Fig. 1).

Furthermore, the cylinder 16 is connected through a channel 18 provided with a check valve 19 to the bottom of an auxiliary cylinder 20 in which an auxiliary piston 21 called an "pendulum body" works. This pendulum body divides the cylinder 20 into two chambers, namely a lower chamber 20 a and an upper chamber 20 b. From the latter leads the delivery line 22 of the injection pump, which is provided with a check valve 23 and is connected to the injection nozzle (or injection nozzles) which is to be supplied with fuel by the relevant injection pump (s).

In the upper chamber 20 & of the cylinder 20, a return spring 24 is arranged, which the pendulum body 21 seeks to press against a shoulder 25 which is the lowest position of the pendulum body in the Cylinder 20 is determined.

The two chambers 20 ″ and 20 b are connected to one another via a channel 26 which has a throttle point with a variable cross section, which is changed by a cock 27 which is controlled by member 4 of the speed regulator. Furthermore, a closure member is provided for the channel 26 which closes this channel during the downward movement (delivery stroke or upward stroke) of the piston 15, but opens it during the downward movement (downward stroke) of this piston. Preferably, a single part is used as a closure member for channel 26 and channel 16 of the speed regulator. For this purpose, the slide 6, which already forms the closure member of the channel Ib, has a second groove 8a (or a second transverse channel), which opens the channel 26 simultaneously with the opening of the channel Ib through the groove 8, while the channel 26 and the channel Ib are closed at the same time when the slide 6 is adjusted so that the grooves 8 and 8 α no longer coincide with their channels Ib and 26 respectively.

To control the slide 6 in the manner described, the lower end of the cylinder 7, in which the slide 6 works, is connected to the upper end of the cylinder 16 through a channel 28. Furthermore, a return spring 29 acts on the slide 6 and tries to hold it against a shoulder 30 which determines the position of the slide 6 in which it opens the channel 1b and the channel 26.

Finally, an outlet channel 31 is also provided on the cylinder 20, which with one end in the wall of the cylinder 20 and with its other end opens into the channel 1, which the memory 2 feeds via the channel la.

The arrangement shown in Fig. 1 works as follows: When the piston 15 rises in the cylinder 16, it first closes the inlet line 17 and 1 b closes. The spring actuating the check valve 19 is expediently stronger than the spring of the slide 6. When the slide 6 has come into the position in which it closes the channels 1b and 26, the piston 15 pushes the liquid in the cylinder 16 through the channel 18 into the chamber 20 a of the cylinder 20, whereby the pendulum body 21 is driven upwards in this cylinder, whereby it conveys liquid from the chamber 20 & over the check valve 23 and the delivery line 22 to the injection nozzles to be fed by the injection pump. As soon as the underside of the pendulum body 21 exposes the outlet channel 31, the excess liquid conveyed by the piston 15 is fed to the reservoir 2 through the channels 1 and 1 a. At the moment in which the piston 15 begins its decline, the slide 6 opens the channels 26 and Ib, and the pendulum body 21 goes down in the cylinder 20, where he liquid located in the chamber 20 a via the channel 26 and that of The throttle point regulated by the cock 27 is transferred into the chamber 20 & of the cylinder 20. The free cross section of the throttle point in the channel 26 is controlled by the member 4 of the speed controller so that this cross section is smaller, the greater the speed forming the control factor.

The decrease of the pendulum body 21 is braked by this throttle point, the more the larger it is the velocity is, and from a certain velocity onwards, as a result of the phenomenon that is to be called "fluid impact," its decline will occur the shorter and the one transferred to chamber 20 & The smaller the amount, the greater the driving speed of the piston 15, which is to the the speed forming the control factor is proportional.

FIG. 2 shows another embodiment of the object of FIG. 1.

The embodiment according to FIG. 2 has two essential differences compared to the embodiment of FIG. 1 on.

In FIG. 2, member 4 of the speed controller is used directly to change the cross section of the throttle point connected to channel 26. For this purpose, the channel 26 opens on both sides of the cylinder 4 a, in which the member 4 is displaceable, in these, and the member preferably has a groove with a conical bottom 4 b , which depending on

the position of the member 4 in its cylinder 4 α the Channel 26 throttles more or less.

Furthermore, in the case of FIG. 2, the pulsating flow rate feeding the memory is not from the cylinder 16, in which the piston 15 works, but from the chamber 20b of the cylinder 20. For this purpose, the pendulum body 21 contains a channel 32 which at one end into the top of the pendulum body and at its other end opens into the side wall of the pendulum body, where the channel is extended by a groove 32 a, which runs on a surface line facing the outlet channel 31, this channel 31 then being provided with a check valve 33. It should be noted that the force with which the valve 33 is pressed against its seat by its spring must of course be less than the force with which the pressure valve 23 is pressed against its seat by its spring, but greater than the pressure with which the liquid enters the chamber 20 δ of the cylinder 20 when it is transferred from the chamber 20 a into the latter, so that even if the pressure in the memory 2 is practically equal to atmospheric pressure, the liquid transferred into the chamber 20 b can not escape to the memory 2.

To discharge the excess liquid conveyed by the piston 15 and to stop the Pendulum body 21 in its uppermost position is still a second outlet line 31a on cylinder 20 provided, which after their exposure through the underside of the pendulum body at the end of the upward stroke the same allows the excess liquid conveyed by the piston 15 to escape to the outside.

In the device shown in FIG. 2, the greatest useful stroke of the pendulum body, ie the stroke at which the pendulum body 21 conveys fuel from the chamber 20 & into the delivery line 22, is equal to h, while the pendulum body discharges liquid during the remainder of the upward stroke Hh the chamber 20 δ via the channel 32 and the channels 31 (with valve 33) and la in the memory 2 promotes.

In the case of FIG. 3 is considered to be associated with the cruise control pulsating pump uses the pump, which at the same time is the feed pump for feeding the cylinder 16 the injection pump is.

In the device shown in FIG this feed pump formed by a widened part 15 α of the piston 15, which the plunger of the Piston 15 forms and works in a cylinder 34 in which a spring 35 is also housed, which the plunger 15 a firmly connected to the piston 15 is constantly in contact with a cam 36 holds, which through its rotation, the reciprocating movement of the arrangement 15-15 α generated.

A feed line 37 opens into the cylinder 34 and is exposed by the piston 15 a forming a plunger when it is at its bottom dead center. Furthermore, in the cylinder 34 at a certain distance above the feed line 37, a first feed channel 38 provided with a check valve 39 opens, which feeds the liquid conveyed by the piston 15 a at the beginning of its upward stroke (stroke d) to a pneumatic reservoir 40 in which the Liquid is stored and pressurized by an air cushion 41. When at the end of the next downward stroke the piston 15, 15 exposes the inlet line 17, some of the liquid stored in the reservoir 40 passes through the dip tube 42, the open end of which is near the bottom of the reservoir 40, and the inlet channel 17 into the cylinder 16 of the injection pump and fills this cylinder. A safety valve 43, which prevents an excessive increase in pressure in the memory 41 and at the same time as

The cleaning valve is attached to the channel 42, 17.

So that the transfer pump 15 α, 34 also forms the pulsating pump for feeding the memory of the cruise control according to the invention, a second feed channel 44 is provided on the cylinder 34, which is provided with a check valve 45 and the interior of the cylinder 34 with the memory 2 a of the Controller connects. The opening through which the channel 44 opens into the cylinder 34 is arranged so that it remains covered by the piston 15 α during the first part d of its upward stroke and only at the moment with the interior of the cylinder 34 by means of an in the piston 15 a attached channel 46 is connected, in which the piston has executed this part d of its upward stroke and is about to close the opening through which the feed channel 38 opens into the cylinder 34. As a result, the liquid is conveyed into the two reservoirs 40 and 2 a one after the other and not simultaneously.

The memory 2a is shown in FIG Device provided with an air cushion 47, which the pumped into the memory 2 a liquid pressures. The outlet 3 of this memory is as in the on F i g. 1 and 2 shown devices controlled by a piston 12 which opens this outlet the more the drive speed increases of the piston 15 α and thus the pressure in the memory 2 a increase.

The free end of a channel or immersion tube 48 which is located near the bottom of the memory in order to always remain in contact with the liquid opens into the liquid mass located in the memory 2 a. This tube 48 is extended by a channel Ib , which is controlled by a closure member 6 so that the pressure prevailing in the memory acts on the control member 4 only during the period in which the piston 15a promotes core liquid into the memory.

As in the device of Fig. 2, the control member 4 directly regulates the throttle point in the channel 26, which connects the two chambers 20 a and 20 b of the auxiliary cylinder 20 and from the slide 6 like the channel Ib during the upward stroke of the piston 15, 15 α is closed. The operation of the speed regulator and its effect on the injection pump, the various parts of which are denoted by the same reference numerals as the corresponding parts of the pump shown in Fig. 1, are the same as in the device shown in this latter figure, so that no further details needs to be entered.

Claims (4)

Patent claims: 1. Hydraulic speed controller for injection pumps of internal combustion engines with a pul- sizing pump, which is driven at a speed which changes depending on the speed forming the control factor, this pump delivering liquid to a pressure accumulator, to which a throttled outlet is provided, so that the prevailing in this accumulator acts on a control element the pressure acting on the injection pump is variable depending on the speed of the pump, characterized in that in the connection (1 b) between the accumulator (2 or 2 a) and the regulating element (4) to be adjusted by the accumulator pressure, a pulsating Pump-controlled closure member (6) is switched on, which interrupts said connection, while the pulsating pump (15, 16, Fi g. 1 and 3 or 206, 21, Fig. 2) pumps liquid into the memory, but between two successive delivery periods the connection (1 b) releases. 2. Hydraulic speed controller according to claim 1, characterized in that the free cross section of the throttled outlet (3) by a control slide (12) on which the in the memory (2 or 2ä) in front of the outlet (3) prevailing pressure against a restoring force acts, is controllable in such a way that the free cross section is variable in the same direction as the drive speed of the pulsating pump (15, 16, FIGS. 1 and 3, or 20 b, 21, FIG. 2). 3. Regulator according to claim 1, characterized in that the closure member (6) is hydraulic by either of the pulsating pump itself (Figs. 1 and 3) or of one with the pulsating Pump synchronously running pump (15, 16) displaced liquid is controlled. 4. Regulator according to claim 1, for injection pumps, the delivery of which is stopped at each delivery stroke by opening an outlet opening, characterized in that it is used through the outlet opening (31 or 31a) flowing fuel to feed the memory (2 or 2 a) . Considered publications:
Additional patent specification No. 63 755 to French patent specification No. 1 048 428; Belgian patent specification No. 432 308. 1 sheet of drawings 609 538/113 3.66 © Bundesdruckerei Berlin