US1752379A - Internal-combustion engine - Google Patents

Description

April l, 1930. J. B. GOODWIN INTERNAL COMBUSTION ENGINE 4 Sheets-Sheet yFiled NOV. 9, 1925 FIEJE- J. B. GooDwIN 1,752,379

INTERNAL COMBUSTION ENGINE Filed Nov. 9, 1925 4 Sheets-Sheetv 2 April 1, 1930.

. ig a mon/vnu April l, 1930- J.- B. GooDwlN 1,752,379-

INTERNAL, GOMBUST ION ENGINE Filed Nov. 9, 1925 4 Sheets-Sheet 5 f [neuron John oodW/n y I i arrabnn April l, 1930. J. B. GooDwlN.

f INTERNAL coMBUsTIoN ENGINE Filed Nov. 9, 1925 4 sheets-sheet 4 60 c/u//n A Trane rs INVENTM f Joh/7 8l' lPatented pr.4 1,- 1930 UNITED Application led November This invention relates to internal combustion engines, of the type generally known as Diesel or oil engines, and has for its object the rovision of an improved lighter engine of t is character, by eliminating the sudden and enormous strains that may arise in the ordinary Diesel engine on combustion. More particularly, the invention has reference to -the provision of means for reducing the pressure within the main or working cylinder at which combustion is eected without a material reduction in the power or Working eficiency of the engine. prise an auxiliary or compensating cylinder in communication with t e working cylinder, the compensating cylinder piston being normally opposed by resilient force, such as a spring or compressed air., This force may be varied to correspond to the maximum pressure selected for the working cylinder, thus when said maximum pressure in the .working cylinder is reached, the compensating piston is acted upon to overcome its 0posing force,l and as it moves into its c liner it increases the volume of the wor ing` cylinder ina proper ratio, thus preventing t efurther increase of pressure in the working cylinder and at the same time maintaining the maximum predetermined pressure while the piston of the compens'atin cylinder completes its stroke, or until comustion is effected. The compensating piston may be described as having a cushioning effect. After combustion is effected, the compensating piston is restored to its normal position by the opposing force acting thereon. This will be better understood from the detaile description hereinafter.

Another object of the invention is to provide an improved device for controlling the volume of the fuel injection into the workingY cylinder.

A furtherobject of the invention is to provide novel means for controlling the timeof said fuel injection.

A still further object of the invention is to provide means for securing atomization of widely varying quantities of fuel, that is,

from a few grains per injection to the maxi- Thse means com- 9, 1925. Serial No. 67,738.

mum that Vmay be burnt in theworliing cylinder.

A further object of the invention is to provide an improved solid injection nozzle, in which small openings are eliminated to prevent clogging from dirt or impurities usually present in the fuel oil. 4 While air injection nozzles may accomplish the same result, the chilling effect of the blastrequires the use of higher pressures, and such nozzles are more complicated and expensive, requiring high pressure air compressors.

The invention possesses other advantageous features, sonie of which with the foregoing will be set forth at length in the following description where I shall outline in full that' form of the invention which .Ihave selected for illustration in the drawings accompanying and forming part of the present specification. In said drawings I have shown several forms of my inventiombut I do not desire to be limited thereto, since the invention as set forth in the claim may be embodied in a plurality of other forms.

Referring to the drawings:

Figure 1 is an elevation of an engine embodyin my invention illustrating the work- -ing an compensating chambers and parts of the controlling mechanism, said latter parts being shown holding the fuel vdischarge piston in its retracted positiom Fig. 2 is a, vertical section taken on the line 2-2 of Fig. 1,. but with the fuel discharge piston and its cooperating lparts shown in its extended position.

Fig. '3 lis a section taken on the line 3-3 of Flg. 1.

Fig. 4 illustrates the pressure chamber for the compensating piston and an air receiver connected therewith.

Fig. 5 isa sectional view of a xnodilied form of means for opposing the compensating piston.

Fig. 6 showsan indicator card of the usual Diesel engine with the changes in characteristics obtained by an engine embodying my invention also indicated thereon.

In the drawings I have shown a main 0r Working cylinder 1, provided with the usual exhaust 2, air inlet 3 as indicated in dotted lines and piston 4, as best shown in Fig. 2. The upper end 5 of the cylinder 1 is preferably formed with a s herical surface. At its upper end the cylin er 1 is provided with a 5 compensating cylinder 6 in communication with said cylinder 1, the compensating cylinder 6 being provided with a piston 7. In

small engines in which but a single fuel nozzle is employed, the compensating cylinder l is preferably positionedA on one s'ide of the vertical axis of the cylinder l; however in large engines which have cylinders of a larger bore, the compensating cylinder is preferably coaxial with the working cylinder and a plurality of nozzles are arranged concentric therewith. The face 8 of piston 7 is also spherical and coincides with the spherical surface 5 when the piston 7 is in its normal position as shown in Fig. 2. It is to'be understood that the working cylinder head may as'- sume other forms. Preferably the cylinders 1 and 6 are formed by a single casing 9, which 'is provided with the usual water cooling passage 10 having an linlet 11 and outlet 12. The

6 agri-fthe rear portion of piston 7 is extended into'fthe chamber 14 to form a piston 15 therein as shown in Fig. 2. The piston 7 is preferably in the form of a hollow bodyforming a cooling chamber 16 in which water is circulated through the pipes 17. A receiver 18 is provided which communicates with cham-l ber 14. through a pipe 19. The receiver 18 is provided for the purpose of providing a large volumejgpf/air under compression to oppose the movement of piston 15 so thatl the dis-y placement of air due to the movement of said pistonshall not cause an undue rise in the pressure of the air resisting the movement of said piston 15 and thereby raise the maximum pressure within the working-cylinder. From the fore oing detailed-description, the operation of t e parts described will be readily understood from a brief description Ain connection with Fig. 5'. y

. Inthe first downward stroke of theworking piston 4, air enters the working cylinder 1 throu h inlet 3 in the usual manner. end o 'the stroke, the working cylinder 1 is yfull of air at `practically atmospheric pressure, ready for the compression stroke. At thistime, the piston 7 is in its lower or outer position by reason of the ressure within the cylinder 14, as shown in ig. 2. In the next stroke of the piston 4, the air is compressed to the required pressure, usually about 400 pounds per s uare inch, while the temperature rises to between- 1000 F. to 1100 F. 06' Let it be assumed that the maximum 'pressure Iinch on a full compression stroke. v Obviouscylinder 6 is open atboth ends and the casing 9 is formed with an external flange or shoulv At theA selected for working is 400 pounds per square inch and' that the working cylinder 1 and piston` 4 are designed to produce a maximum compression of say 500 pounds per square ly, if means are connected with' the cylinder 1 adapted to yield when the selected maximum pressure is reached, 400 pounds per square inch in the present case, the pressure in the cylinder 1 will not exceed that pressure, although the piston 44 has not completed its compression stroke. In the present form of .device embodying my invention, the piston 7 provides such yielding means. The chamber 14 and its piston 15, are designed so as to apply an opposing force to the inward movement of the piston 7 up to the maximum pressure selected for the cylinder 1. Thus, when the pressure within the working cylinder 1 reaches, say 400 pounds persquare inch, the pressure within cylinder 14 is overcome and the compensating piston 7 moves into its cylinder 6. This action obviously increases the volume of the cylinder 1 and the several parts are so designed that the increase in volume is just suicient to maintain the compression within the cylinder l at the predetermined maximum value.

Obviously, as the pressure within the working cylinder 1 decreases, that is after 95 the combustion takes place and the piston 4 starts on its downward stroke, the piston 7 moves toward its open end and follows up the piston 4 to the limit of its travel, thereby maintaining the above mentioned mafximum working pressure in cylinder 1 for a considerable portion of the travel of the piston. 4. To compensate yfor leakage losses in the chambers 14 and 18, and more particularly, to provide a dash pot for the compensating piston 7 and prevent injury thereto by its forci- 7 ble return whenthe shoulders forming the piston 15 strike against the shoulders of the cylinderv 6, I have provided an inlet 20, having a suitable check valve 21, extending into the chamber 14 on the return side of the pis-l ton 15, and an outlet 22, similarly positioned l y,which ycommunicates through a by-pass 23 with the compression side of the piston 15. l

The by-pass is controlled by a suitable check 115 -rear of the piston 15 however is sufficiently 125 retarded by the valve 24 to provide a dash pot action and prevent the forcible return of the same against the casing 9. To prevent the building up of excessive pressures within said cylinders 14 and 18 a relief valve 13b 25, of the automatic or manual type, may be provided. 'It is of course understood that in a multi-cylinder type of engine, the several cylinders 14 may be connected to a common chamber 18, designed to maintain the necessary pressure. As shown in Fig. 5, the receiver 18 may be omitted and the chamber 14 may be provided with a suitable spring 25 to perform functions similar to that shown above. Y v

It is ofcourse understood that air is supplied to chambers 14 and 18 by any suitable compressing means, not illustrated, and that the pressure in said chambers may be varied. By varying the resistance opposing the movement of the compensating piston, compensation may be made for differences in altitude and forignition points of fuels. This feature renders the engine particularly ,suitable for aero service as well as automotive workk in mountainousv countries, and alsomakes it readily adaptable for various fuels. Another particular advantage of this arrangement isthat the smaller engines may readily be started for example by a'hand'crank, by reducing the pressure opposing the compensating piston, thereby reducingthe compression and employing for starting purposes only a lighter grade of-fuel than that on which the engine usually runs.

The advantageous results obtained by this arrangement will be better understood from the indicator card shown in Fig. 6, in which the full lines have reference to an engine not provided with my compensating cylinder. Therein, ab represents the first or suction stroke, bc the compression of the air more or less adiabat-ically, lcclthe dcombustion during the admission portion of the next stroke, and

le the following expansion of the mixture until the exhaust valve opens at e, when for the remainder of the stroke ef,'the pressure falls more rapidly as some of the gasesare expelled; fa represents the'final stroke in which all the products of combustion are exhausted through the exhaust valve. Let it be assumed that latthe point :I: on bc the compression has reached the' maximum selected pressure of 400 pounds per square inch. At this instant, the piston 7 functions as'above described,and the pressure remains at this value as indicated by my in dotted lines which indicates the combustion and partial expansion during the initial portion of the next stroke. The dotted line ya indicates the following expansion of the mixture until the exhaust valve opens .in an engine embodying my invention. From this it will be seen that with a lower pressure in the working cylinder, I secure'substantially the same power as has heretofore been secured with greater pressures. l e j The means for supplying fuel oil to the working cylinder 1 comprise a fuel supply pipe 26 which communicates through passages 27,'28 and 29 with said cylinder 1. The

passage 27 -"fcommunicates with one end, shown 'as the upper end in Fig. 2, of a small chamber or reservoir 30 for holding a charge of fuel oil and is controlled by an inlet valve v31 acting against the inner end of the passage ,and more fully described'hereinafter. From this it will be seen that when fuel is supplied through the supply pipe 26, thevalve. 31 is unseated, opening communication with the fuel charge chamber 30, and this chamber, as

well as passages 28 and 29 are filled with fuel oil until 'the same is expelled therefrom by means no w' to be described.

The opposite or lower end of the fuel charge chamber or cylinder 30, communicates through a sleeve 37 with a cylinder 38,and a` rod 37 yis slidable therein and projects therefrom. A piston 39 iswithin the cylinder 38 and means are provided for reciprocating the piston 39 intermittently at predetermined periods, as will be later described.

Obviously, the upward movement of the piston 29 toward the sleeve 37 causes it to engage the rod 37 and push itinto the chamber 30 thereby forcing the fuel oil therefrom into the working cylinder 1 through the passages described. f

It is clear that the'stroke of the piston 39 determines the quantity of fuel oil supplied ltothe working cylinder and means are pro- 'vided for varying the stroke thereof. It is also apparent that .the piston 39 must operate at' definite predetermined periods so as to force the fuel oil into the working cylinder 1 at the time the desired pressure is built up therein. To accomplish these' results, I have provided novel, simpleand efficient means shown in Figs. 1, 2 and 3.

W'ithin'the cylinder 38, I have provided a strong' heavy coil spring 40, which acts against the rear face of the piston 39 and against 'the bottom of the cylinder.- In the present case, I have shown the bottom of the cylinder 38 as formed by a cover plate 41, bolted to' the casing of cylinder 38. The lower end of spring 40 is also shown as seated in a cup 42, which may be moved by means of screws 43 whereby the tension of the spring 40 may be adjusted in a manner readily understood. It is obvious that other means may be used for actuating the piston 39, such for example las an air chamber similar to the. chamber 14 above described. The cylinder 38 is also provided with a by-pass 44connecting the opposite sides of the piston 39, to provide a dash pot similar to that described above in connection with piston 15. The piston 39 is provided with a stem 45, shown as hollow in the present case, although not necessarily so, which projects through the cylinder bottom 41. The lower end of the stem is provided with a solid bifurcated member 46 which pivotally supports a link 47 between its bifurcations on a pin 48. The opposite end of the link 47 is connected with a rod 49, which is reciprocated, vertically as shown in Figs. 1 and 2, by a suitable cam, at definite intervals. The cam is not shown as this arrangement is well understood in the art and not deemed necessary to be shown herein. Between the pin 48 and the rod 49, I have provided an adjustable fulcrum about which the link 47 acts. By varying this fulcrum the l stroke of the piston 39 may be regulated, and

in this manner, the supply of fuel supplied t'o the working cylinder 1 regulated.` This fulcrum comprises a-roller 50 mounted on a crank shaft 51 which is journaled in a substantially vertical member 52, extending alongside of the projecting portion of the piston stem 45. The upper end of the member 52 is pivotally connected with the bottom plate 41 of cylinder 38 and at its opposite endis pivotally connected with a manually operated lever 53, which is shown asy horizontal. From theforegoing description, it will be seen that the roller 50 is eccentricall mounted on the member 52, and that the movement of the member 52 by the rod 53 varies the distance of the fulcrum of the link 47, thereby controlling the distance of .the back stroke of the piston 39 and consequently the amount of fuel discharged tothe working cylinder.

. The upward movement of the rod 49 causes the piston 39 to move downwardly, oroutwardly in its cylinder, compressing the spring 40, and placing the piston in operative position'to discharge the fuel oil into the work-v ing cylinder 1 however, since this action must take place in the briefest interval and at a definite predetermined time, means are provided for holding the piston 39 in such operative position,and,releasing the same at the proper instant, thus permitting the spring 40 to act andoperate the piston. For this'purpose,"atripping member 54 is'pivoted on the member 52 at .55, one end 54 of which is adapted to strike a locking member 56 which is fixed onthe crank or cam shaft 51 of the roller 50. The movement of the member 56 ina counter-clockwise direction is prevented lby a stop 57, and it is urged against said stop i by a sprmg 57%*1The opposite end 54 of the tripper 54 is engaged by a trigger 58, pivoted on a collar 59 which loosely surrounds the projecting end of `valve stem 45. The collar 59 ,has a relatively iixed position in which it is held by a .spring 60 acting upon it and a suitable. collar 61 iixed on the said stem 45. 'iihe spring 60 urges the collar 59 against another fixed element hereinafter referred to. 'The trigger 58 is inthe form of a lever pivoted at an intermediate point on a fulcrum 62. As above stated, one of its ends is adapted to strike the tripper 54, andits opposite end is normally urged downwardly by a spring 63. Between the-fulcrum 62 and the said opposite end, the trigger 58 is engaged by a link 64 which is reciprocated by a rod 65. The rod 65 is reciprocated by means of acam, not shown, but which acts at predetermined intervals in a well understood manner. Having described the structural details of the' time controlling means for the fuel discharge, it is believed that a short description of the operation will suiiice.

Letit be assumed that the rod 49 has moved upwardly in which case the stem 45 has moved downwardly, compressing spring 40, the action having taken place through the `link 47 which is fulcrumed on the. roller 50; At this time, the member 56 abuts the stop '57, having been moved to this position by spring 57. At this` time, the axis of the roller 50 i's below the axis of the crank shaft 51 and the piston is thereby held in its retracted position. 'At the proper instant, the rod 65 is moved upwardly causing the trigger arm 58 to lmove downwardly, pushing the shoulder 54 about the pivot 55, and moving y the tripping member end 54 counter-clockwise, thereby moving the member 56 clockwise. The motion of member 56 displaces the axis of the crank shaft 51 to one side 'of' the axis of the roller 50, and since the spring 40 is acting to push the piston 39 up, the link 47 is acting upwardly upon the roller 50. Since the axis of the crank shaft 51 is now olf center with respect to the axis of roller 5 0, the result is that the arm 56 is thrown back` quickly, thereby relieving the fulcrum point of support and allowing the piston 39 to move upwardly. Through the action of a spring 66, the tripper 54 is restored to its normal position, and the members 50 and 56 are restored to their former/positions by the action of spring 57 The cycle of operation described is repeated for the next. fuel discharge.

In order to provide means for adjusting the time of discharge, the upper face of the collar 59 is provided with a series of inclined surfaces 67, adapted to cooperate with similar inclined surfaces 68 on a collar 69, which abuts against the bottom plate 41 of cylinder 38. 'The collar 69' is rotatable on the stem 45 and provided with an operating handle 70. Thus by rotating the collar 69, the collar 59 may be adjusted vertically on the stem 4,5, and consequently the time at which the trigger 58, which is carried on the collar 59, operates the tripper 54 may be varied.

The valve 36 which controls the fuel supshoulder for one end of a coiled spring 75,

the opposite end of said spring acting against the inner surface of the end 71. The aperture 90 is enlarged near its upper end to accommodate an external shoulder 76 on the sleeve 88, and is held in the opening 90 by a nut 77. The external surface of the sleeve 88 from the shoulder 76 to its upper end is smooth. By rotating the sleeve 88 the unit is moved from and toward the valve seat 36. Obviously, this movement varies the distance between the end 71 and washer 7 3, thereby varying the tension of the spring 7 5. By varying the tension of this spring, the distance the valve seat 36 opens may be'controlled and in this manner, I control the rate of How of the fuel oil to the working cylinder. Varying` the tension on the inlet valve spring not only has an effect on the distance the valve opens, but it also governs the degree of atomization and in its relationship to the tension of spring 40 the duration of the iniection period. This variation of atomization is due to the variation of fuel iniection pressures. The upper end of the sleeve 88 is closed bv a threaded cap 78. whichv is provided with a central passage' 79. closed b v a thumb screw 80. which provides a bleed valve to permit the exhausting of any air from the fuel supply system that may be in the same before starting the engine.

It will he observed 'that the passage 29 is comparatively large and that the valve is seated on the inner end thereof.V By this arrangement, clogging bv dirt and other impurities in the fuel oil is prevented. since the passage is large enough to permit the passage therethrough of the same ordinarily. and if such` particles lodge in the passage, they are expelled therefrom when the fuel is in-V iected into the cylinder 1. As shown in Fig. 2, thel valve 36 is moved outwardly and may be adjusted to secure a fine atomization,'

the comparatively sharp edges of the valve seat producing the atomizing action.

From the foregoing. it will be seen that l have produced a highly flexible engine in which a fine atomization of widely varying Quantities or qualities of fuel is possible, the flexibility being further facilitated by a refined control of the time of fuel iniection as well as'the quantity of fuel injected. Flexibility over a wide range of speeds is not a` characteristic of the usual type of heavy oil engines; however an engine embodying my invention is of light Weight and highly ilexible, especially adapting it to a wide range of service such as for example automotive, rail, aero and marine service. While I have shown my invention as embodied in a two cycle type of engine, it is of course understood that the invention may be embodied in other types.

I claim An internal combustion engine comprising a working cylinder, a compensating cylinder, a wall enclosing a pressure chamber of greater diameter than the compensating. cylinder, a piston within the compensating cylinder adapted to be acted upon by pressure within the working cylinder, a piston provided' in said pressure chamber and secured to said iirst piston, and means for maintaining the pressure within said pressure chamber, said means including a by-pass formed in and providing communication thru said wall from one side of the piston provided in the pressure chamber to the opposite side thereof, a. check valve secured in said wall and adapted to work in said bypass, and an air inlet valve opening into the atmosphere from one side of the piston provided in the pressure chamber. y

In testimony whereof, l have hereunto set in hand.

y JOHN B. GOODWIN.

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