United States Patent
`Eichler et al.
`
`r 19]
`
`3,865,089
`[ I I ]
`[451 Feb. 11, 1975
`
`[54] METHOD AND SYSTEM TO REDUCE
`POLLUTING EMISSION FROM INTERNAL
`COMBUSTION ENGINES
`Inventors: Dieter Eichler, Hochberg; Otto
`Glockler, Renningen; Richard
`Bertsch, Asperg, all of Germany
`
`[ 75]
`
`[73] Assignee: Robert Bosch GmbH,
`Gerlingen-Schillerhohe, Germany
`
`[22] Filed:
`
`June 29, 1972
`
`[21] Appl. No.: 267,562
`
`[ 30]
`
`Foreign Application Priority Data
`Jan. 21, 1972 Germany ............................ 2202786
`
`[52] U.S. Cl... ....................... 123/117 R, 123/117 A
`Int. Cl. .............................................. F02p 5/04
`[5 I]
`[58] Field of Search ......... 123/117 R, 117 A, 119 D
`
`[56]
`
`3.426,737
`3,447,518
`3,515,368
`
`References Cited
`UNITED STATES PATENTS
`Walker ........................... 123/117 A
`2/1969
`Walker ........................... 123/117 A
`6/1969
`Kelly ............................... 123/117 A
`6/1970
`
`3,561,410
`3,603,298
`3,626,909
`3,631,845
`3,670,709
`3,687,120
`3,707,954
`
`2/1971
`9/1971
`12/1971
`1/1972
`6/1972
`8/1972
`I /1973
`
`Soeters ........................... 123/117 A
`Toda ............................... 123/ll7 A
`Hayashida ....................... 123/11 7 A
`Walker ........................... 123/117 A
`Eckert ............................ 123/119 D
`Lenz ............................... 123/11 7 A
`Nakada ........................... 123/117 A
`
`Primary Examiner-Charles J. Myhre
`Assistant Examiner-Cort Flint
`Attorney, Agent, or Firm-Flynn & Frishauf
`
`[57 J
`ABSTRACT
`After the engine has started, and while it is still cold
`and before it has warmed up, the ignition is delayed in
`addition to the normal delay to such an extent that
`combustion of fuel will persist during the exhaust
`stroke of the engine to accelerate ahe warm-up time of
`the exhaust system of the engine; this delay may be set
`in the range of from I ou to 25° after deadcenter of the
`piston during the power stroke. When the engine, or
`the exhaust system, or components thereof have
`reached a predetermined temperature, ignition timing
`is then controlled as usual.
`
`19 Claims, 17 Drawing Figures
`
`·-·--,
`I
`I .
`I
`·-t
`301-
`
`i
`
`32
`
`BOSCH-DAIMLER EXHIBIT 1003
`
`Page 1 of 24
`
`

`
`PATENTED FEB 111975
`
`3.865..089
`
`SHEET 1 OF 5
`
`Fig.1
`
`NO
`{r:pm)
`5000
`
`Page 2 of 24
`
`

`
`PATENTED FEB 1 i 1975
`
`SHEU 2 OF 5 ·
`
`3.865,089
`
`Fig.2
`
`/
`
`/
`
`32
`
`Fig.3
`
`38
`
`0
`
`·-·-·-.·
`
`"kw
`
`·Fig. 4
`__ t __
`38
`
`KW
`
`·-·-,
`I
`!I ,,
`II
`·-1
`301-
`
`li
`
`Fig.5
`
`44
`/,..138-
`0 ~
`
`/
`
`/
`
`/
`
`/
`
`nJpu
`
`n
`
`n
`
`Page 3 of 24
`
`

`
`PATENiEO FEB 1 1 1975
`
`3,865,089
`
`SHEET 3 OF 5
`
`Fig.6
`
`32
`
`Fig.7
`
`38
`
`·kw
`
`0
`
`<~:
`
`n}pu
`
`0
`
`46
`
`Fig.8
`
`·kw
`
`Fig.9
`
`·kw
`
`r50
`
`r - - i3~~
`
`/
`
`/
`
`·~ /
`
`/r-~38-
`
`/
`
`n
`
`n
`
`Page 4 of 24
`
`

`
`PATENiEO FEB 111975
`
`3_,865,089
`
`SHEET 1J OF 5
`
`Fig.10
`
`"kw
`
`Fig.11
`
`38
`
`Fig. 12
`
`"kw
`
`"kw
`
`,--~~-.
`
`/
`
`/
`
`61
`
`/
`0 _../
`
`·~
`~ 0
`
`59
`
`n,pu
`
`Fig.13
`
`62
`
`/r-138-
`
`/
`
`/
`
`/
`
`n
`
`n
`
`Page 5 of 24
`
`

`
`PATENTED FEB 111975
`
`3.865,089
`
`SHEET SOF 5
`
`Fig.14
`
`64
`
`63
`
`"kw
`
`1
`
`0
`
`Fig.15
`
`38
`
`39
`
`<7
`
`59
`
`n,pu
`
`Fig.l6
`
`"kw
`
`38
`,r-- t::. --
`65
`
`/
`
`/
`
`/
`0 _../
`
`.kvv
`
`I
`
`I
`
`Fig.17
`
`66
`/,.. \.3a-
`
`/
`
`/
`
`/
`
`n
`
`n
`
`Page 6 of 24
`
`

`
`1
`METHOD AND SYSTEM TO REDUCE POLLUTING
`EMISSION FROM INTERNAL COMBUSTION
`ENGINES
`
`Cross reference to related patent and applications:
`U.S. 3,483,851, Reichardt, December 16, 1969.
`The present invention relates to a method, and to a
`system to reduce noxious components in the exhaust
`emission of internal combustion engines, and more par(cid:173)
`ticularly to reduce the noxious components which arise
`during warm-up time of the engine.
`Internal combustion engines require higher and
`higher standards of reduced polluting emission. In one
`system, utilizing electronic fuel injection, the air-fuel
`mixture is matched to the various operating parameters 15
`of the internal combustion engine and, indeed, also to
`ambient parameters within which the engine operates,
`such as ambient air pressure or the like. With such sys(cid:173)
`tems, the air-fuel ratio can be so set that the combus(cid:173)
`tion is an optimum. Electronic fuel injection systems
`have lower polluting emissions during normal opera(cid:173)
`tion of the engine than carburetor-type engines; how(cid:173)
`ever, it has been shown that polluting exhaust during
`the start-up time of the engine, and during the warm-up 25
`period of the exhaust system is particularly high. Tests
`have shown this comparatively large polluting compo(cid:173)
`nent during warm-up, for example the well known CVS
`("constant volume sampling") test. A comparatively
`large portion of the noxious components in the exhaust 30
`gases are generated during the warm-up phase of the
`engine.
`It is an object of the present invention to provide a
`method, and a system utilizing the method which is par(cid:173)
`ticularly suited to effectively reduce the polluting com- 35
`ponents in the exhaust emission of internal combustion
`engines during the warm-up period of the engine sys(cid:173)
`tem, and particularly of the exhaust portion thereof.
`Subject matter of the present invention
`Briefly, upon starting of the engine, and particularly 40
`after the engine has started and runs smoothly and
`without bucking, the ignition timing of the ignition sys(cid:173)
`tem of the engine is changed to be delayed to such an
`extent that combustion of the fuel will be extended and
`may, for example, even persist during the exhaust 45
`stroke of the engine. Preferably, the ignition timing is
`delayed to !0° to 25° of crankshaft angle after the
`upper dead-center of the piston in the cylinder. This
`delay is then reduced and removed to the normal igni(cid:173)
`tion timing control when a component of the engine 50
`system, typically the exhaust system of the internal
`combustion engine has a predetermined temperature.
`The system of the present invention can be made in(cid:173)
`expensively and can be utilized as an adaptation to ex(cid:173)
`isting engines, while operating reliably. The system, in 55
`accordance with a feature of the invention, utilizes the
`normally employed and well known vacuum dia(cid:173)
`phragms to change the position of a timing disk in the
`distributor by means of an adjustment rod. The move(cid:173)
`ment of the adjustment rod, setting the delay of the ig- 60
`nition timing is controlled by a stop which limits the ex(cid:173)
`cursion of the adjustment rod, the stop changing posi(cid:173)
`tion in dependence on the operating temperature aris-
`ing within the engine system, and more particularly
`within the exhaust system of the internal combustion 65
`engine.
`Reference in the specification will be made to the air
`number, denoted lambda (A). This air number A is a
`measure of the composi~ion of the air-fuel mixture. The
`
`3,865,089
`
`2
`number A is proportional to the mass of air and fuel,
`and the value of this number A is one (A= 1.0) if a stoi(cid:173)
`chiometric mixture is present. Under stoichiometric
`conditions, the mixture has such a composition that, in
`5 view of the chemical reactions, all hydrocarbons in the
`fuel can theoretically combine with the oxygen in the
`air to provide complete combustion to carbon dioxide
`and water. In actual practice, even with a stoichiomet(cid:173)
`ric mixture, unburned non-combusted hydrocarbons
`10 and carbon monoxide are contained in the exhaust
`gases.
`The invention will be described by way of example
`with reference to the accompanying drawings. wherein:
`FIG. 1 is a diagram indicating the influence of the air
`number A to the exhaust emissiorns of an internal com(cid:173)
`bustion engine;
`FIG. 2 is a schematic showing of the ignition distribu(cid:173)
`tor retardation system, with a vacuum chamber shown
`20 in greater detail in section, to retard the ignition during
`warm-up of the engine;
`FIG. 3 is a schematic graph indicating change in igni(cid:173)
`tion timing in dependence on speed and inlet manifold
`vacuum;
`FIG. 4 is a graph indicating change in ignition timing
`with partial loading and idling of tlhe engine, when cold;
`FIG. 5 is a graph similar to FIG. 4, but when the en(cid:173)
`gine has warmed;
`FIG. 6 is a diagram similar to FIG. 2, and illustrating
`a different embodiment;
`FIG. 7 is a graph similar to FIG. 3 and indicating igni(cid:173)
`tion change with respect to speed and inlet manifold
`vacuum of the system of FIG. 6;
`FIG. 8 is a diagram similar to FIG. 5 illustrating
`change in ignition timing in a partially loaded and in an
`idling engine, when cold;
`FIG. 9 is a graph similar to FIG. 8 with the engine
`warm;
`FIG. 10 is a schematic diagram similar to FIG. 2 and
`illustrating another embodiment;
`FIG. ll is a graph similar to FIGS. 3 and 7, but with
`respect to the embodiment of FIG. 10;
`FIG. 12 is a graph similar to FIGS. 4 and 8 but with
`respect to the system of FIG. 10;
`FIG. 13 is a graph similar to FIGS. 5 and 9, but with
`respect to the system of FIG. 10;
`FIG. 14 is an illustration similar to FIG. 2, but illus(cid:173)
`trating a different embodiment;
`FIG. 15 is a graph similar to FIGS. 3, 7 and 10, but
`with respect to the embodiment of FIG. 14;
`FIG. 16 is a graph similar to FIGS. 4, 8 and 12, but
`with respect to the system of FIG. 14; and
`FIG. 17 is a graph similar to FIGS. 5, 9 and 13, but
`with respect to the embodiment of FIG. 14.
`The graph of FIG. 1 illustrates the emission of nitro(cid:173)
`gen-oxygen compounds, hydrocarbons, and carbon
`monoxide with respect to air number A. Curve 20 illus(cid:173)
`trates the nitrogen-oxygen compounds NO.r, curve 21
`illustrates emission of unburned hydrocarbons, and
`curve 22 emission of carbon monoxide. The air number
`A= I when a stoichiometric fuel-air mixture is present,
`which is, usually, by mass, about I to 14.4 for gasoline
`internal combustion engines. The •curves clearly show
`that the CO emission decreases as J\. increases; the C-H
`emission decreases until A has a value of about 1.1,
`then is essentially horizontal, and as A increases even
`more, the unburned hydrocarbon emission increases
`again. The NO.r emission increases rapidly at a value of
`about A = I .0 and has a maximum at about A = I .1.
`
`Page 7 of 24
`
`

`
`3,865,089
`
`3
`Thereafter, the NO.r emission again is reduced substan(cid:173)
`tially. The curves of FIG. 1 are drawn for a fully loaded,
`warm internal combustion engine, at operating temper(cid:173)
`ature. Upon starting, and during warm-up of the en(cid:173)
`gine, and when the exhaust system is still cold, the ex- 5
`haust emission of CO and unburned hydrocarbons is
`substantially increased. It is therefore desirable that the
`exhaust system of the internal combustion engine be
`warmed as soon as possible, and particularly when ther(cid:173)
`mal and catalytic reactors (or only catalytic reactors) 10
`are used, so that carbon monoxide and hydrocarbons
`can be reduced by reacting the carbon monoxide and
`the hydrocarbons after they have been emitted from
`the cylinder of the internal combustion engine.
`Delaying the ignition to an extreme extent, for exam- 15
`pie in the region of I 0° to 2So after the upper dead(cid:173)
`center position of the piston of the internal combustion
`engine has the effect that when the exhaust valve
`opens, the combustion of the fuel has not completely
`terminated yet, thus rapidly heating the exhaust system. 20
`Flames may actually penetrate into the exhaust system
`of the internal combustion engine, to rapidly heat the
`exhaust manifold and the surrounding parts. The ex(cid:173)
`treme delay of ignition decreases the thermal efficiency 25
`of the internal combustion engine, which substantially
`decreases the NO.r emission. After the exhaust system
`has heated and has reached a predetermined tempera(cid:173)
`ture, which is sensed by a thermostat, the additional
`and extreme delay in ignition can be reduced so that 30
`the output manifold will not reach a temperature which
`is excessive and which may cause damage.
`Referring now to FIG. 2, wherein a system to carry
`out the invention is illustrated: The ignition timing is
`delayed to about 10° to 25° after the upper dead-center 35
`position of the piston in the cylinder. FIG. 2 illustrates,
`schematically, the adjustment disk 23 of a distributor
`for an internal combustion engine. This adjustment
`disk 23 is operated over a rod 24 by an ignition delay
`chamber 25 and an ignition advance chamber 26. The 40
`delay chamber 25 can be utilized to retard the spark
`during idling, in order to improve the emissions during
`idling. By setting the spark about S0 delayed, that is, so
`after dead-center, the combustion within the combus(cid:173)
`tion chamber of the engine is retarded to such an extent 45
`that the exhaust will, even when the engine is idling,
`reach a sufficient temperature which is desirable to re(cid:173)
`duce exhaust emission. The delay by the chamber 25 is
`limited by means of a stop 27 which engages in a notch
`28 of rod 24.
`Spark advance chamber 26 operates, as well known,
`to advance the spark at partial loading.
`In order to obtain a further delay of the spark to a re(cid:173)
`gion of from 10° to 2S 0 after dead-center, the stop 27
`is formed to be movable, preferably by being controlled
`by an electromagnet or solenoid coil 29. Upon opera(cid:173)
`tion of coil 29, stop 27 is withdrawn from notch 28 of
`rod 24, so that the rod 24 can travel over a greater
`path, in order to still further delay the ignition timing.
`Magnet 29 is operated by a temperature-sensitive
`switch 30 which is in thermal conductive relation to the
`exhaust system, schematically indicated as manifold E
`in FIG. 2, and which is thus operated when the exhaust
`manifold reaches a predetermined temperature. Ther(cid:173)
`mostat switch 30 can physically be mounted in contact
`with the exhaust system, as illustrated at 30', or can be
`separately operated.
`
`4
`When the thermostatic switch 30 is in a first position,
`that is, during warm-up and before the exhaust system
`E has reached the predetermined temperature, switch
`30 is closed, and electromagnet 29 is operated, that is,
`stop 27 is pulled in. This permits extreme delays by the
`delay chamber 25 during the warm-up time of the en-
`gine. Switch 30 additionally controls a valve 31 which
`interconnects the delay chamber 25 with the suction
`side of the inlet manifold during the warm-up time of
`the exhaust system. The advance chamber 26 is sepa(cid:173)
`rated from the inlet manifold, or the suction portion
`thereof during warm-up of the exhaust system.
`The temperature-sensitive switch 30 additionally
`controls an auxiliary valve 33 which is connected in a
`bypass to the throttle 34 in the inlet manifold 35 of the
`internal combustion engine. The bypass to throttle 34
`is provided so that the idle speed does not decrease
`when the ignition timing is delayed by extreme values.
`During the warm-up of the exhaust system, the auxili(cid:173)
`ary control valve is opened, so that the bypass to throt(cid:173)
`tle 34 is opened. After the engine has warmed up, the
`additional valve is closed and thus the bypass to throttle
`34 is likewise closed. The stop 27 is again engaged so
`that the maximum ignition delay may be only S0
`, upon
`idling. Additionally, after warm-up and after the ex-
`haust system has reached its operating temperature, the
`temperature-sensitive switch 30 will control the control
`valve 31 to change to its second switching position in
`which the spark advance chamber 26 is connected with
`a port 36 located adjacent the throttle 34 in the inlet
`manifold, or as part of the carburetor assembly. Fur(cid:173)
`ther, the delay chamber 25 is connected to a port 37 in
`the inlet tube, or the carburetor, which is likewise lo(cid:173)
`cated close to the throttle 34.
`The ports are usually located in a portion of the car(cid:173)
`buretor assembly, for example a throttle body thereof.
`FIG. 3 illustrates the change of the ignition timing
`with respect to engine speed, or with respect to inlet
`manifold vacuum, respectively. The ordinate illus(cid:173)
`trates, in degrees with respect to dead-center, the igni-
`tion timing, delay being below zero and advance being
`above·zero. As can be seen from curve 38, at low speed
`there is little spark advance; as the the speed increases,
`that is, in intermediate speeds, the spark advances
`gradually and at high speed remains constant, and ad-
`vanced. Curve 39 illustrates spark advance at partial
`loading. Curve 40 illustrates spark retardation or delay
`with respect to vacuum in the inlet manifold. As shown,
`delay of the ignition occurs only when a predetermined
`vacuum is sensed, this delay, as above referred to,
`being roughly so after dead-center. Curve 41 shows the
`extreme delay warm-up of the exhaust system of the in(cid:173)
`ternal combustion engine. As seen, the change first is
`55 similar to that of curve 40; yet, at the point where with
`curve 40 the stop 27 would engage, the curve, never(cid:173)
`theless, continues since, in warm-up, stop 27 has been
`withdrawn so that further spark delay is possible.
`FIG. 4 illustrates the spark advance curve 38, for full
`load operation. Curve 43 illustrates the characteristic
`of change in ignition timing for partial or for idling,
`when the engine is cold. Curve 43 illustrates that it is
`practically parallel to the spark advance curve 38 (in
`65 dashed line), the distance between the two curves 38
`and 43 being determined by the extreme time delay
`during warm-up of the exhaust system of the internal
`combustion engine.
`
`50
`
`60
`
`Page 8 of 24
`
`

`
`3,865,089
`
`5
`FIG. 5 illustrates the full load spark advance charac(cid:173)
`teristic 38, in broken lines. Additionally, a graph 44 is
`shown which is representative of partial loading and
`idling when
`the
`internal combustion engine has
`reached operating temperature. This curve shows that 5
`when the internal combustion engine is warm, delay is
`effective only when the throttle is closed; as soon as the
`throttle is opened and the engine has reached speeds
`which are above the idling speed, the idling delay is dis(cid:173)
`connected and the partial load spark advance becomes
`effective.
`FIGS. 3, 4 and 5 have their abscissas drawn to the
`same origin, that is, the zero angle is offset for clarity.
`FIG. 6 illustrates a different embodiment of the pres(cid:173)
`ent invention in which similar and similarly operating
`components as those in the embodiment of FIG. 2 have
`been given the same reference numerals, and will not
`be described again in detail.
`The change in the position of the stop member 27, as
`well as the change-over of the auxiliary valve 33 is ac(cid:173)
`complished pneumatically, rather than electrically as in
`the example of FIG. 2. Stop member 27 fits within the
`notch 28 of the operating rod 24 between the distribu(cid:173)
`tor advance-retard setting disk 23 and the advance(cid:173)
`retard chamber or diaphragm assembly 25, 26. The
`stop 27 is changed in position in dependence on the
`pressure, or rather vacuum arising within diaphragm
`chamber 42. The additional valve 32 itself is changed
`by a vacuum diaphragm chamber 45 in its position.
`Both of the vacuum diaphragm chambers 42, 45 are
`controlled by a vacuum line 46, connected to control
`valve 47 which interconnects the vacuum chambers 42,
`45 with the suction port 32 within the suction system
`of the internal combustion engine during the warm-up
`period of the engine. The control valve 47 additionally
`provides a connection from the start delay or retard
`chamber 25 to the suction chamber 32 during the
`warm-up period of the exhaust system of the engine.
`The spark advance chamber 26, during this warm-up
`period of the exhaust system, is connected with a vent
`bore 48 in the control valve 47, so that the spark ad(cid:173)
`vance chamber 26 is unloaded and cannot effect any
`change of the position of the operating rod 24.
`After the exhaust system has warmed up, control
`valve 47 is changed over in its position by the tempera(cid:173)
`ture sensing switch 30, so that the spark advance cham(cid:173)
`ber 26 is connected with the port 36 in the inlet or suc(cid:173)
`tion portion 35 leading to the engine, close to the throt(cid:173)
`tle 34. Further, the second position of the control valve
`47 interconnects line 46 with the vent bore 48 of the
`control valve, so that both spark retard chambers 42
`and 45 are vented and unloaded. Further, the second
`position of the control valve 47 interconnects the spark
`delay chamber 25 with a bore 38 in the vicinity of the
`throttle 34, within the inl~t suction system of the inter(cid:173)
`nal combustion engine.
`The characteristics of the ignition timing, resulting
`from this arrangement, are similar to those of FIGS. 3,
`4 and 5, corresponding to the arrangement of FIG. 2.
`FIG. 7 illustrates the full load characteristic curve 38
`for spark advance; curve 39 illustrates the spark ad(cid:173)
`vance characteristic at partial load. Further, character(cid:173)
`istic curves 40 and 41 illustrate the spark retardation,
`curve 41 illustrating the extreme retardation during
`warm-up of the exhaust system. FIG. 8 illustrates, in
`broken line curve 38, the entire characteristic, which
`is similar in shape to the characteristic curve 49, which
`
`6
`is again similar to curve 43 of FIG. 4. As can be seen,
`during warm-up, extreme retardation of the spark is ef(cid:173)
`fected, in that the stop 27 is withdrawn from notch 28
`of rod 24. The retardation is sup.erimposed to the full
`load characteristic curve 38, whnch is the curve gov(cid:173)
`erned by the centrifugal control of spark timing, so that
`the overall characteristic of curve 49 is similar, in shape
`and appearance, to that of the full load characteristic
`38.
`10 The broken line curve 38 of FIG. 9 again represents
`the full load characteristic, and is shown together with
`the overall characteristic 50, which corresponds to the
`overall curve 44 in FIG. 5.
`Embodiment of FIG. 10: The distributor timing plate
`15 23 is connected over operating rod 24 with three vac(cid:173)
`uum chambers. The rod 24 can change position de(cid:173)
`pending on the relative pressures within spark advance
`chamber 51, spark retardation chamber 52 and addi(cid:173)
`tional retardation chamber 53. The usual idling retar-
`20 dation is carried out by means of the retardation cham(cid:173)
`ber 52, which is fitted against a plate 54 acting as a stop
`member. During warm-up of the exhaust system of the
`internal combustion engine, when the ignition should
`be retarded additionally further, the membrane 55 of
`25 the additional chamber 53 moves towards the right,
`counter the force of a spring 56, so that the stop of the
`normal retarding position of chamber 52 is changed.
`These two movements are superimposed. The normal
`idling retardation, commanded by chamber 52, and the
`30 additional retardation commanded by chamber 53 pro(cid:173)
`vides for a larger position change of rod 24 and thus for
`a greater delay of the ignition timing.
`The various chambers 51, 52, 53 are controlled from
`a control valve 57 which, in dependence on the posi-
`35 tion of the temperature sensitive switch 30 has two dif(cid:173)
`ferent control positions. During warm-up of the ex(cid:173)
`haust system of the internal combustion engine, the ad(cid:173)
`ditional chamber 53 is connected over control valve 57
`with the suction distributor 32 in the suction system of
`40 the internal combustion engine. The idling retardation
`chamber 52 is directly connected to bore 37 in the inlet
`tube 35, in the vicinity of the throttle 34. The spark ad(cid:173)
`vance chamber 51 is connected with a vent bore 58
`during warm-up of the exhaust system of the engine
`45 and is separated from the suction system of the internal
`combustion engine by the contr.ol valve 57. During
`warm-up of the exhaust system, a bypass is connected
`in parallel to throttle 34, the bypass being controlled by
`auxiliary valve 33 which opens a line from a bore 59 lo-
`50 cated in advance to the throttle in the inlet tube throttle
`body of the carburetor, and adjacent the throttle 34,
`and connects with the inlet manifold 32.
`Operation: After warm-up, and when the control
`55 valve 57 has been switched over to its second switching
`position, that is, when the exhaust system is at operat(cid:173)
`ing temperature, the bypass to the throttle 34 is closed
`by means of the chamber 45. The additional chamber
`43 is separated from the inlet manifold 32 and con-
`60 nected with the vent bore 58. The spark advance cham(cid:173)
`ber 51 is connected to bore 36 located close to the
`throttle 34 in the throttle body of the inlet to the inter(cid:173)
`nal combustion engine.
`The characteristics resulting from this operation are
`65 seen in FIGS. 11-13 and, as is apparent, are similar to
`the characteristics previously dis.cussed. In FIG. 11,
`curve 38 illustrates the full load relationship; curve 39
`the partial load spark advance. Curve 40 illustrates the
`
`Page 9 of 24
`
`

`
`3,865,089
`
`50
`
`7
`spark retardation at idling, curve 59 illustrates the
`spark retardation when the motor is cold. The curve 59
`illustrates that, at a predetermined inlet manifold pres(cid:173)
`sure, the spark retardation is effective to a greater ex(cid:173)
`tent than in the examples of FIGS. 2 and 6, as indicated
`by the steeper portion of the curve at 60. This more
`rapidly acting retardation of the spark is obtained by
`superimposition of the movement of the idling spark
`retard chamber 52 with the additional chamber 53.
`The full load characteristic 38 is again shown in FIG.
`12; the ignition distributor characteristic 61 is illus(cid:173)
`trated for idling and partial load operation, with the en(cid:173)
`gine cold. As can be seen, at idling, an extreme ignition
`retardation is obtained. As the throttle is opened, the
`under-pressure for the spark retardation chamber 52
`drops, so that at partial loading only the retardation
`due to the additional chamber 53 is effective which,
`again, is superimposed over the full load characteristic
`38, and is thus parallel thereto.
`FIG. 13 illustrates the full load characteristics at 38
`in broken lines and, in curve 62, illustrates the total
`change in position of the ignition timing in partial load
`and idling operation when the engineis warm. As can
`be seen, curve 62 is shifted with respect to curve 61 by
`the value of the additional time delay of the cold inter(cid:173)
`nal combustion engine, and by the partial load spark
`advance.
`Embodiment of FIG. 14: The distributor ignition tim-
`ing disk 23 again is changed in position by adjusting rod
`24, which is commanded by a spark advance chamber
`51, idling retardation chamber 52 and additional cham(cid:173)
`ber 53. The interconnection between the chambers 51,
`52 and 53 with the vacuum system of the internal com(cid:173)
`bustion engine is effected over a control valve 63. The
`first position of valve 63, as shown in the drawing, cor- 35
`responds to a position in which the exhaust system has
`temperature, whereas
`reached operating
`not yet
`change-over to the second switching position occurs
`when the temperature sensitive switch 30 has operated.
`In the first switching position, control valve 63 inter- 40
`connects the idling retardation chamber 52 and the ad(cid:173)
`ditional chamber 53 with the inlet manifold 32 of the
`internal combustion engine. The spark advance cham(cid:173)
`ber 51 is connected with a vent bore 64. A bypass, in
`parallel to throttle 34, is controlled by auxiliary valve 45
`33. It is opened by chamber 45, controlled by the valve
`63, by being connected by valve 63 with the inlet mani(cid:173)
`fold 32 of the internal combustion engine. The idling
`retardation chamber 52 and the additional chamber 53
`are similar to the embodiment of FIG. 10.
`After the warm-up of the exhaust system of the inter-
`nal combustion engine, switch 30 will change over and
`valve 63 will assume its second switching position, in
`which the spark advance chamber 51 is connected with 55
`bore 36 in the throttle body of the carburetor.
`The characteristics of the arrangement of FIG. 14 are
`illustrated in FIGS. IS to 17. The full load characteris(cid:173)
`tic 38, and the partial load characteristic 39 are similar
`to those of FIG. 1 I. Likewise, the delay curves 40 of 60
`the idling delay and curve 59, with the steeper portion
`60 representative of the additional delay during warm-
`up are similar to the characteristics illustrated in FIG.
`II. FIG. 16 illustrates in curve 38 the full load line
`when the engine is cold, and at curve 65 the overall 65
`characteristics upon partial loading or idling with cold
`engine. The difference between curve 65 (FIG. 16) and
`curve 61 (FIG. 12} arises in the interconnection of the
`
`8
`common spark idling delay chamber 52. In the embodi(cid:173)
`ment of FIG. 10, the spark idling delay chamber 52 is
`connected at all time with bore 37 located close to
`throttle 34 in the throttle body of the internal com bus-
`S tion engine; in the arrangement in accordance with
`FIG. 14, however, the idling retardation chamber 52,
`during warm-up of the engine, is connected with the
`inlet manifold 32 of the internal combustion engine and
`after warm-up is connected to bore 37 located close to
`10 the throttle 34 in the throttle bottle of the carburetor
`or the inlet to the engine.
`FIG. 17 illustrates, again in broken line at curve 38,
`the full load characteristics with the warm engine and
`curve 66 the overall change of the ignition timing upon
`15 partial load and idling with warm internal combustion
`engine.
`The present invention has been illustrated in connec(cid:173)
`tion with a specific arrangement to change the position
`of the distributor timing; various and modifications
`20 may be made within the inventive concept.
`The present invention has been illustrated in connec(cid:173)
`tion with highly schematic drawings. For a complete
`discussion of operating parameters and spark advance
`and retardation, reference is made to "Principles of
`25 Automotive Vehicles," U.S. Government Publication
`TM 9-8000, chapter on "Battery Ignition," with the
`that the linkages interconnecting vacuum
`proviso
`chambers to the breaker plate or element determining
`ignition timing should be capable of turning the plate
`30 so that the spark can be retarded for a greater degree
`than heretofore customary in internal combustion en-
`gines.
`We claim:
`1. System to reduce polluting components from the
`exhaust of internal combustion engines during warm(cid:173)
`up of the engine, in combination with an engine having
`an inlet manifold, a throttle, timing control means op(cid:173)
`erable within a predetermined range for timing the igni(cid:173)
`tion of the engine, within said range, with respect to
`piston position, and an exhaust system including an ex(cid:173)
`haust manifold, said pollution reducing system com(cid:173)
`prising
`means (25, 26, 51, 52) continuously effective during
`engine operation to adjust the ignition timing of the
`ignition system within said range, comprising a
`spark advance vacuum chamber means (25, 26) to
`advance or delay ignition timing within said range
`with respect to dead-center position of the piston;
`adjustment link means ( 24) connected to the ignition
`timing adjustment means;
`means controlling additional retardation of ignition
`timing of the ignition system, to a delay value of
`such magnitude that combustion will persist during
`at least a portion of the exhaust stroke of the en(cid:173)
`gine in addition to the adjustment" of the ignition
`timing, within said range, due to said continuously
`effective ignition timing means, comprising a con(cid:173)
`trol valve (31) interconnecting the spark delay
`chamber (25) to the inlet manifold of the engine
`during warm-up time of the engine and before the
`engine has reached said predetermined tempe·ra(cid:173)
`ture, said valve (31) connecting the delay chamber
`to a suction port (37) located in the vicinity of the
`throttle (34) in the inlet to the engine;
`and means (30} responsive to temperature arising in
`the exhaust system of the engine during operation
`thereof, said temperature responsive means includ-
`
`Page 10 of 24
`
`

`
`3,865,089
`
`10
`
`9
`10
`ing means controlling the extent of travel of said
`12. System to reduce polluting components from the
`link element to disable control by said additional
`exhaust of internal combustion engines during warm(cid:173)
`ignition timing retardation means when said tem(cid:173)
`up of the engine, in combination with an engine having
`perature responsive means senses that a predeter(cid:173)
`