US3563223A

US3563223A - Perfectly balanced double-acting reciprocating machine

Info

Publication number: US3563223A
Application number: US791327*A
Authority: US
Inventors: Kenjiro Ishida
Original assignee: Shizuoka University NUC
Current assignee: Shizuoka University NUC
Priority date: 1968-01-30
Filing date: 1969-01-15
Publication date: 1971-02-16
Anticipated expiration: 1988-02-16
Also published as: SE349115B; DE1905244A1; CH475470A; FR2000962A1; GB1263171A

Abstract

A perfectly balanced reciprocating engine comprising at least one linear reciprocating rod and a rotating and revolving crank mechanism. The crank mechanism has a crank radius l and rotates about a crank axis and also revolves about another axis having an eccentricity-l from the crank axis in the opposite direction of crankshaft rotation to effect a linear reciprocating motion with a stroke 4l. The crank mechanism further comprises a balance weight of mass positioned m1 at the opposite side of the crank pin and at a distance R1 from the crank and also another balance weight of mass m2 secured to a rotatably mounted eccentric collar to effect revolution of the crank directly in the opposite side of the crankshaft positioned at a distance R2 from the crank axis. Both balance weights are determined to satisfy the formulae ml m1R1 and (m+m1 m3)l m2R2 wherein, m is the reciprocating mass, m3 is the total rotating mass except for the masses ml and m2 and l is the crank radius. The engine according to the invention provides a perfectly balanced operation.

Description

United States Patent [54] PERFECTLY BALANCED DOUBLE-ACTING 3,258,992 7/1966 Hittell 123/55 3,277,743 10/1966 Kell 123/55 3,329,134 7/1967 Llewellyn 123/55 Primary Examiner-Wendell E. Burns Attorney-Robert El Burns ABSTRACT: A perfectly balanced reciprocating engine comprising at least one linear reciprocating rod and a rotating and revolving crank mechanism. The crank mechanism has a crank radius 1 and rotates about a crank axis and also revolves RECIPROCATING MACHINE about another axis having an eccentricity-l from the crank axis In the opposite direction of crankshaft rotation to effect a 9 Claims, 8 Drawing Figs.

linear reciprocating motion with a stroke 41. The crank U.S. Cl. mechanism further comprises a balance weight of mass posi- 123/51 123/53, 123/55 tioned m at the opposite side of the crank pin and at a [51] Illl. Cl. 75/06, distance R from the crank and also another balance weight of Fozb F02) 25/08 mass m secured to a rotatably mounted eccentric collar to ef- [50] Fleld of Search 123/53, 51, f m r volution of the crank directly in the opposite side of the 55 192 crankshaft positioned at a distance R from the crank axis. Both balance weights are determined to satisfy the formulae [56] References C'ted ml=m and (m+m =m )l =I1l2R wherein, m is the re- UNITED STATES PATENTS ciprocating mass, m is the total rotating mass except for the l,090,647 3/1914 Pitts 123/53 masses m, and m and I is the crank radius. The engine accord- 3,175,544 3/1965 Hughes l23/55 ing to the invention provides a perfectly balanced operation.

4 2o l as l3 l9I7 I I P 24 O i 27 A 26 m 4 saw 2 UF 8 PATENTEBFEBIBIQH sum 9 UF 3 Fig. 4

PERFECTIJY BALANCED DOUBLE-ACTING RECIPROCATING MACHINE The present invention relates to a reciprocating machine, and more particularly to a perfectly balanced reciprocating engine providing one ormore linearly reciprocating rods and a rotating and revolving crank mechanism.

Known reciprocating engines provide conventional crank mechanisms including one or more connecting rods which oscillate on a plane vertical to rotating axis at every rotation of the crank by such an arrangement, it is very difficult to utilize the opposite side of the piston to the combustion chamber as a compression chamber. Furthermore, unbalanced forces caused by inertia of the reciprocating mass of the conventional engine cannot be theoretically balanced, so that a vibration problem usually accompanies the known engine.

The present invention utilizes a crank mechanism having a crank radius I rotating about a crank axis and revolving about another axis at an eccentric distance I from the crank axis in the opposite direction of the crankshaft rotation to effect linear reciprocating motion of the rod connected with the crank pin with a stroke of 41 The crank mechanism further provides a balance weight of mass m, positioned directly on the opposite side of the crank pin about its axis at a distance R, from the crank axis and another balance weight of mass m, secured to a rotatably mounted eccentric collar to effect revolution of the crank directly in the opposite side of the crankshaft about its axis at distance R, from its axis. Both balance weights are determined in accordance with the formulas ml=m R, and (m-i-m +m l =m,R,, wherein m is the reciprocating mass, m,, is the rotating mass (rotating mass of rotating portion except the equivalent reciprocating mass and the balance mass), and l is the crank radius or amount of eccentricity. Thus, the machine or engine is provided with a linearly reciprocating rod and the engine is theoretically balanced. The principle of the-perfect balancing is described in the relating application of the same inventors.

The primary object of the present invention is to provide a dcubleacting internal combustion engine utilizing both sides of the piston as combustion chambers and being perfectly balanced as to unbalanced forces.

Another object of the present invention isto provide double-acting internal combustion engine, providing aligned. two cylinders and straightly reciprocating integrally providable rods, the underside of the pistons being utilized as precompression chamber of the two cycle engine, and the unbalanced forces being perfectly balance According to a feature of the. present invention a perfectly balanced reciprocating machine comprises a casing, at least one cylinder means having cylinder head means and secured to the casing, wall means secured to said cylinder means to define a space between said cylinder head and the casing, piston means slidably accommodating in the cylinder means and defining said space'into two working spaces by the both two-cycle reciprocating engine crankshaft having a planetary motion system by eccentric gear according to one embodiment of the present invention,

FIG. 2 shows a sectional view along; line 2-2 of FIG. 1,

FIG. 3 shows a longitudinal sectional view of a single cylinder double-acting perfectly. balanced two-cycle reciprocating engine of crankshaft planetary motion system by internal gear according to the second embodiment of the present invention,

FIG. 4 shows a sectional view along line 4-4 of FIG. 3,

FIG. 5 shows a longitudinal sectional view of an opposedcylinders double-acting perfectly balanced two-cycle reciprocating engine of crankshaft planetary motion system by eccentric gear according to the third embodiment of the present invention,

FIG. 6 shows a sectional view along line 645 of FIG. 5,

FIG. 7 shows alongitudinal sectional view of an opposedcylinders double-acting perfectly balanced two-cycle reciprocating engine of crankshaft planetary motion system by internal gear according to the fourth embodiment of the present invention, and

FIG. 8 shows a sectional view along line 8-8 of FIG. 7.

V Referring now to FIGS. 1 and 2, a cylinder 1 having a cylinder head 2 is secured to a casing 3 through a lower cylinder head 4. A piston 5 is slidably positioned in the cylinder 1 to define upper and lower combustion chambers 2' and 4' and is secured by such as a pin 6 to upper end of a linearly reciprocating rod 7 having upper and

lower seal rings

8 and 9 to slidably pass through a center opening of the lower cylinder head 4. The connecting rod 7 is connected at the lower end thereof to a crank pin 10 of a crank 11. The crank pin 10 lies on a crank axis A and the crank 11 lies on a crankshaft axis P. The crank 11 provides two crank arms 12 and 13 which are secured to the crank pin 10 and

crank journals

14 and 15 which are rotatably supported through needle bearing 16 and 17 to eccentric collars 1 8 and 19 respectively.

side surfaces of the piston, connecting rod means connected with one end thereof to said piston means and slidably engaging to the wall means, crank means having at least one crank pin each connecting with another end of said rod means at a crank radius 1, at least one eccentric collar means rotatably supported by said casing and having support means rotatably supporting the crank means at the same amount of eccentricity-I, means to cooperate the crank means and the eccentric collar means to rotate the crank and collar means at the same uniform angular velocity and in reversedirection each other and to effect linear reciprocating motion of the rod means, and balance weight means to effect above-mentioned perfect balance.

Further and more specific objects, features and advantages of the present invention will become apparent in the following description of preferred embodiments, by way of example, wherein reference is made tothe accompanying drawing, in which: 5

FIG. 1 shows a longitudinal sectional view along line 1-1 of FIG. 2 of a single cylinder, double acting, perfectly balanced The

eccentric collars

18 and 19 provide openings to accommodate the

needle bearings

16 and 17 at amount of eccentricityl from its axis which is the same length to the crank radius and are rotatably supported through

bearings

20 and 21 by the casing 3 to rotate on a center axis 0 in the reverse direction and at the same angular velocity to rotation of the crank 11.

To effect rotation and revolution of the crank 11 and to effect linear reciprocating motion of therod 7, gears are provided as shown in FIG. 2. A gear 23 is secured to the outer end of the crank 11 and gears 24 and 25are secured to he outer end portions of the

eccentric collars

18 and 19 respectively. A

shaft 26 is rotatably supported by'the casing 3 and is secured to an eccentric gear 27 having amount of eccentricity-l which meshes with gear 23 and has the same number of teeth with that in the gear 23, and

gears

28 and 29 which have the same number of teeth with that in the

gears

24 and 25 mesh with

gears

30 and 31 which are securedto another shaft 32 supported by the casing 3. Also,

gears

28 and 29 are secured to the shaft 26. The

gears

30 and 31 also mesh'with the

gears

24 and 25 so that the-eccentric collars 18 and I9 rotate in opposite direction and at the same angular velocity to rotation of the crank 11. A gear 33 is secured to the shaft 32 and meshes with a gear 34 which is securedto akick-starting shaft 35.

In this embodiment, the cylinder 1 is constructed as two cycle port scavenging engine. Thus, the cylinder 1 provides an exhaust port 37 and inlet ports, 38 and 39 which are controlled by head 2 and to the lower end of cylinder a rotary valve 40. The outer periphery of the rotary valve: 40 provides gear teeth which meshes through a gear 41 idly supported by the casing 3 with a gear 42 secured to the eccentric collar 19. The

inlet ports

38 and 39 are connected through a Roots blower 43 to an inlet passage 44 providing a carburetor 45.

Spark plugs

46 and 47 are provided to the upper cylinder head 2 and to the lower end of cylinder 1 respectively.

Balance weights having a total mass m, are secured to the crank arms 12 and 13 on the opposite side of the crank pin 10 about the crankshaft axis P at a distance R from the crank axis A which extends through the center of the crank pin 10. Other balance weights having a total mass m are secured to the

eccentric collars

18 and 19 on the opposite side of the

crank journals

14 and 15 at distance R from the crankshaft axis P. As theoretically explained in the above-mentioned related application, the masses m and m are determined to satisfy the formulas ml=m R, and (m+m +m;,)l=m R in which m is the reciprocating mass, m, is rotating mass exclusive of the balance masses m and m and l is amount of eccentricity of the eccentric collars l8 and 19 and the crank radius of the crank 11. Thus the engine is balanced perfectly.

Operation of the double-acting two-cycle engine shown in FIGS. 1 and 2 is as follows:

As shown in FIGS. 1 and 2, the upper combustion chamber 2' is at top dead center, whereas the lower combustion chamber 4 is at bottom dead center. At the upper combustion chamber 2',combustion is now taking place and the piston 5 is pushed downwards. The connecting rod 7 secured to the piston 5 is also moved downward. As shown by arrows in FIG. 2, the energy of the combustion gas is transmitted to the crank 11 and is converted to rotation of the crank 11 at angular velocity to on the axis P. The gear 23 secured to the outer end of the crank 11 rotates clockwise with the crank 11 to rotate the eccentric gear 27 counterclockwise at the same angular velocity was the

gears

23 and 27 have the same number of teeth. By rotation of the eccentric gear 27,

gears

28 and 29 and the shaft 26 rotate to produce rotation of the

gears

30 and 31 clockwise on the shaft 32. Thus, the

gears

24 and 25 and the eccentric collars l8 and 19 which are supported by the casing 3 through the

bearings

20 and 21 and supporting the crank 11 through the

needle bearings

16 and 17 at the same amount of eccentricallyJ, rotate counterclockwise at the same angular velocity or on the center axis 0. Thus, the crank 11 rotates on its crankshaft axis P and at the same time revolves around the center axis at an amount of eccentricity-lthe axis P in opposite directions and at the same angular velocity to, so that point A or the center of the crank pin 11 at the crank radius I linearly reciprocates to effect linear reciprocation with a stroke of 41 of the connecting rod 7. The motion is transmitted to the output shaft 32 as rotating motion.

As the piston moves downward, the piston first opens the exhaust port 37 and fresh gas through inlet port 38 is supercharged by the blower 43. After the inlet port 39 is closed off by the piston 5, fresh gas in the lower combustion chamber 4 is compressed until the gas is ignited by the spark plug 47.

At the same time, combusting gas in the upper combustion chamber 2' expands as the downward motion of the piston 5 until the exhaust port 37 is opened by the upper side surface of the piston 5 to effect exhaust of the spent gas. As the piston 5 opens inlet port 38, fresh gas is introduced in the combustion chamber 2 to effect scavenging of the chamber 2'.

As the rod 7 reciprocates linearly, gas seal between the lower cylinder head 4 and the rod 7 can be easily performed by known seal ring means 9, and the combustion gas in the lower combustion chamber produces upward thrust to the piston 5. Thus, in the upper and lower combustion chambers 2' and 4, suction, compression, combustion, exhaust and scavenging cycle are performed at phase difference I80", to produce double-acting cycle internal combustion engine.

The inlet control of the fresh gas is performed by the rotary valve 40 which, in this case, is driven at the same rotation as the eccentric collar 19 through the gears 41 and 42. To effect good scavenging and supercharging, the blower 43 is provided in the inlet passage 44, as no suction pressure is produced in the

combustion chambers

2 and 4.

FIGS. 3 and 4 show second embodiment of the present invention utilizing internal gear to produce linear reciprocating motion of the rod and perfectly balanced feature of the present invention.

In this case, again single cylinder double-acting two-cycle internal combustion engine is shown for the sake of clarity, however, double-acting four-cycle engine can also be produced easily. The upper portion of the engine is similar to the engine shown in FIGS. 1 and 2, the same reference numerals are used to show same or similar parts or portions.

As shown in FIGS. 3 and 4, a piston 5 accommodating in the cylinder 1 and the defining the upper and

lower compression chambers

2 and 4 is shown as integral with a connecting rod 7'. .However, in practice, the piston 5' may be secured to the rod 7' as desired. The lower end of the rod 7' is rotatably supported by a crank pin 10' which may be integral with crank arms 12' and 13 of the crank 11'. Crank journals 14' and 15 are supported through needle bearings 16' and 17 by eccentric collars 18 and 19' which are supported through bearings 20 and 21' by casing 3 respectively.

Gears 50 and 51 are secured to the crank 11' at each side of the crank arms 12' and 13' on the same center P and having pitch circle diameter 2! which is twice to the crank radius or to the amount of eccentricity of the eccentric collars. Internal gears 52 and 53 meshing with the gears 50 and 51 and having pitch circle diameter 4l which is equal to the stroke of the rod 7 and is twice to the pitch circle diameter of the gears 50 and 51, are secured to the casing 3'.

Gears

54 and 55 are secured to the outer end of the eccentric collars l8 and 19 respectively. One or both of the

gears

54 and 55 are meshed with other gear or gears not shown to drive an output shaft not shown. The rotary valve is driven through a gear 56, a shaft 57 which secures the gear 56 and is supported by the casing 3', and a gear 58 meshing with the gear 55 fixed by the collar 19.

As to balancing of the engine, balance weights having total mass m are secured to the crank arms 12 and 13 in the opposite side of the crank pin 10' about axis P at distance R from the center of the crank pin 10 respectively. Another balance weights having total mass m are secured to the

eccentric collars

18 and 19 in the opposite side of the crank journals 14' and 15' about axis 0 at distance R from its center respectively. The masses m and m are determined, as before, to satisfy above mentioned formulas mlf=m R and (m+m +m )=m R,, in which m is reciprocating mass, m is rotating mass. Thus the machine is balanced perfectly.

Operation of the double-acting two-cycle engine shown in FIGS. 3 and 4 is as follows: 7

As shown, at the upper combustion chamber 2' combustion is now taking place and the piston 5 and the connecting rod 7' are pushed downward. The crank 11' and the secured planet gears 50 and 51 rotate clockwise on the center P. At the same time, the planet gears 50 and 51 meshing with the stationary

internal gears

52 and 53 respectively revolve on the center 0 counterclockwise. Thus, the eccentric collars l8 and 19' act as planet carrier of the planet gears 50 and 51 rotating counterclockwise at the same angular velocity at as the crank 11'. As the pitch circle diameter of the

internal gears

52 and 53 is 41 and twice to that of the planet gears 50 and 51, the connecting rod 7 reciprocates linearly along longitudinal axis of the cylinder 1. The output shaft may be connected to one or both of the

gears

54 and 55 which are secured to the eccentric collars 18 and 19' respectively. A small portion of the driving power is divided from the gear 55 through the gear 58, the shaft 57 and the gear 56 to the rotary valve 40 to control inlet of the fresh gas through the inlet passage 44 providing the carburetor 45 and the blower 43 to the

inlet ports

38 and 39.

Combustion and scavenging in the upper and lower combustion chambers 2' and 4' are similar to the engine shown in FIGS. 1 and 2.

FIGS. 5 and 6 show an opposed-cylinders double-acting perfectly balanced two-cycle reciprocating engine of crankshaft planetary motion system by eccentric gear according to the third embodiment of the present invention.

The engine provides concentrically opposed

cylinders

101 and 102 each secured to the casing 103. The

cylinders

101 and 102 provide

inlet ports

104 and 105,

exhaust ports

106 and 107, and scavenging

ports

108 and 109 respectively. Cylinder heads 110 and 111 each having a

spark plug

112 and 113 are secured to the cylinders. The

cylinders

101 and 102 accommodate

pistons

114 and 115 securing to one end of linearly reciprocating connecting

rods

116 and 117 which connect with a crank pin 118 of a crank 119 having crank radius 1.

Thus,

combustion chambers

120 and 121 are formed between the cylinder heads 110 and 111 and the

pistons

114 and 115. The undersides of the cylinders and 102 are sealed by

gas seals

124 and 125 which are secured to

walls

122 and 123, and connecting

rods

116 and 117 are slidably engaged in gas seals 124 and 125-. Thus

precompression chambers

126 and 127 are defined between the

walls

122 and 123 and undersides of

pistons

114 and 115.

The crank 119 consists of crank

arms

130 and 131, crank pin 118 and crank

journals

132 and 133. The crank

journals

132 and 133 are rotatably supported through

needle bearings

138 and 139 to eccentric collars .136 and 137 respectively. The

eccentric collars

136 and 137 provide

openings

134 and 135 to accommodate the

needle bearings

138 and 139 at amount of eccentricity-I from its axis which is the same length to the crank radius and are rotatably supported by the casing 103 through

bearings

140 and 141.

As shown in F165. 5 and 6, a gear 145 is secured to the outer end of the crank 119 and meshed with an eccentric gear 146 having the same number of teeth with that in the gear 145 and secured to a shaft 147 which is supported by the casing 103.

Another gear 148 is secured to the shaft 147 and meshes with one of

gears

149 and 150 secured to a shaft 151.

Gears

152 and 153 meshing with the

gears

149 and 150 and having the same number of teeth with that in the gear 148 are secured to the

eccentric collars

136 and 137 respectively. Output shaft (not shown) may be connected to the shaft 151. Also, auxiliary devices such as a generator and/or'a starter may be connected with the eccentric collar 137.

The operation of the double-acting two-cycle engine shown in FIGS. 5 and 6 is as follows:

As shown the piston 114 is at bottom dead center of the combustion chamber 120 an the piston 115 is at top dead center of the combustion chamber 121. Thus, the combustion chamber 120 is scavenging as the exhaust port 106 and the scavenging ports 108 are both opened; the precompression chamber 126 is at top dead center and the compressed fresh air is delivered to the combustion chamber..120 through the scavenge ports 108. The precompression chamber 127 of the lower cylinder 102 is at bottom dead center and fresh gas is supplied to the chamber throughthe inlet port 105. In the combustion chamber 121 combustion is now taking place to.

drive the piston 115 and the rod 117.

As the

pistons

115 and 114 and the

rods

117 and 116 linearly reciprocate along one longitudinal axis of the

cylinders

102 and 101, the rod 116 and the piston 114 are directly driven upward by the rod 117. The driving force is transmitted to the crank 119, as quiet similar to the engine shown in FIGS. 1 and 2, rotating clockwise. As shown in F IG. 6, the rotation is transmitted to the gear 145, to counterclockwise rotation of the same angular velocity of the eccentric gear 146, rotation of the secured shaft 147, rotation of the gear 148 secured to the shaft 147 and clockwise rotation of the

gears

149 and 150 on the shaft 151, to rotate the

gears

152 and 153 counterclockwise, which are secured to the

eccentric collars

136 and 137 respectively, at the same angular velocity to the gear 145.

As the piston 115 displaces upwards, combustion gas expands, and asthe piston 115 opens the exhaust port 107, the

combustion gas is exhausted. The piston 115 compresses fresh gas introduced in the precompression chamber 127 after the inlet port 104 is closed off by the piston. Then, as the piston 115 opens the scavenge ports 108, the compressed gas in the precompression chamber 127 is delivered to the combustion chamber 121 to scavenge and charge the combustion chamber.

At the same time, compression stroke of the combustion chamber 120 is performed by the piston 114 in the cylinder 101. After the piston 114 closes off the scavenge port 108 and the exhaust port 106, the piston 114 compresses fresh gas in the combustion chamber 120 and the compressed gas is ignited by the spark plug 112 at suitablie timing. Fresh gas is introduced through the inlet port 104 after the piston opens the port 104.

Thus, the upper and the

lower cylinders

101 and 102 are operated as two-cycle internal combustion engine at l phase difference, each having precompression chamber which acts as conventional crankcase compression chamber. How ever, in this case, as the engine provides two cylinders, conventional crankcase compression can never be utilized. Further, compression ratio of the precompression chambers 126 an 127 can be independently determined as desired, lubricant mixture ratio can be very low. Also, as the

rods

116 and 117 linearly reciprocate without any relative motion, the rods can be secured each other, so that the bearing area of the crank pin 118 can be determined very small. Consequently, very compact and effective two-cycle engine is provided.

As the piston 114,

rods

116 and 117 and piston linearly reciprocate as an integral member without any relative motion, the engine can be regarded as a center output tandem engine which can be .seen as old fashioned steam engine or a double-acting engine providing a long piston having both side faces opposing to the combustion chambers and 121 respectively. As can be seen easily, the tandem engine shown in FIGS. 5 and 6 need not long swinging connecting rod and crank mechanism and the engine is perfectly balanced, so that the engine can be easily and advantageously accommodated to many applications as two-cycle or four-cycle engines, compressors or pumps. As a double-acting machine, two independent cylinders accommodate a long piston having rigid connecting rod so that desired characteristic such as precompression scavenging feature can be provided to both surfaces of the piston without any limitation which has been inevitable in the known double-acting machine, thus, very compact and high output machine can be provided.

FIGS. 7 and 8 show opposed-cylinders perfectly balanced two-cycle reciprocating engine of crankshaft planetary motion system by internal gear according to he fourth embodiment of the present invention.

The cylinder unit of the engine shown in FIGS. 7 and 8 is shown quite similarly to that of FIGS. 5 and 6 for the sake of clarity, so that the same reference numerals are used to show similar parts or portions.

The

cylinders

101 and 102 are secured to a casing 103' in line each other, so that the connecting

rods

116 and 117 connected with crank pin 118 of a crank 119' reciprocate linearly along longitudinal axis of the

cylinders

101 and 102.

The crank 119' consists of crank arms and 131', crank pin 118 and crank journals 132' and 133. In this embodiment, gears 160 and 161 having pitch circle diameter 21 are secured to the crank journals 132' and 133 respectively. The crank journals 132' and 133' are rotatably supported through needle bearings 138' and 139 to eccentric collars 136' and 137' respectively. The eccentric collars 136' and 137' provide openings 134 and to accommodate the needle bearings and 141' at amount of eccentricity-l from its axis which is the same length to the crank radius and are rotatably supported by the casing 103' through

bearings

140' and 141. intemal gears 162 and 163 meshing with gears and 161 and having pitch circle diameter 41 are secured concentrically to the eccentric collars 136' and 137'.

Gears

164 and 165 are secured to the eccentric collars 136' and 137 respectively to connect output shaft not shown or auxiliary devices not shown.

As to balancing of the engine, balancing weights are secured to the crank arms and the eccentric collars following to similar process described above, thus perfectly balanced feature is obtained.

Operation of the engine shown in FIGS. 7 and 8 is as follows:

In this embodiment, of the cylinder 101 in the combustion chamber 120 is at top dead center and combustion is now taking place. The combustion energy is tnansmitted to the piston 114 to push the piston downward, thus, the piston 114, the

connecting rod 116, the connecting rod 117 which displaces with the rod 116 without relative motion each other, and the piston 115 moves downward as an integral member. The linear motion of the pistons and rods is transmitted to the crank ll9'to rotate on the axis P, so that the planet gears 160 and 161 rotate along the meshing internal gears 162 and 163. Thus, the planet carrier or the eccentric collars 136' and 137 rotate on the axis at the same angular velocity and in reverse direction to the

gears

160 and 161, and the crank 119. Consequently, linear reciprocating motion of the

rods

116 and 117 is produced.

Operation of the precompression chamber scavenging twocycle internal combustion engine providing the

cylinders

101 and 102 is perfectly similar to the engine shown in FIGS. and 6.

The tandem or double-acting feature described above is also applied to the reciprocating machine shown in FIGS. 7 and 8.

As the reciprocating machine according to the invention is perfectly balanced as single cylinder machine, multiple cylinders machine can also be produced very easily as perfectly balanced, so that numbers and arrangement of the cylinders can be determined as desired to attain desired characteristic or to arrange in limited space.

lclaim:

l. A balanced reciprocating machine comprising: a casing; means defining at least one enclosed cylinder secured to said casing; a piston slidably mounted in said cylinder and dividing said cylinder into two working spaces; means for alternately supplying and exhausting pressurized fluid into and out of each of said two working spaces to effect reciprocation of said piston; a connecting rod pivotally connected at one end thereof to said piston; crank means including a crank pin connected to the other end of said connecting rod at a crank radius 1; collar means eccentrically and rotatably supported by said casing and having support means rotatably supporting said crank means at the same amount of eccentricity-l; means to rotate said collar means and said crank means at the same uniform angular velocity and in reverse directions with respect to each other to effect linear reciprocating motion of said connecting rod; a first balance weight having a total mass :11 secured to said crank means on the opposite side of said crank pin at a distance R, from its axis; a second balance weight having a total mass m secured to said collar means on the opposite side of said support means at a distance R from its axis; and wherein both said balance weights are determined in accordance with the formulas mI=m R 1 and (m+m +m )l=m R.-; wherein m is the total reciprocating mass and m is the total rotating mass exclusive of said balance weights; whereby unbalanced forces caused by said reciprocating mass are balanced.

2. A reciprocating machine as defined in claim 1 wherein said means for alternately supplying and exhausting pressurized fluid comprises at least one inlet means communicating with said working spaces to supply fluid into said working spaces and outlet means communicating with said working spaces to discharge fluid from said working spaces.

3. A reciprocating machine as defined in claim 2 wherein said cylinder further includes ignition means communicating with each of said working spaces and said outlet means includes exhaust port means alternately covered and uncovered by said piston during its reciprocal movement.

4. A perfectly balanced reciprocating machine comprising a casing, at least one pair of cylinder means having cylinder head means secured to the casing, each pair of said cylinder means being secured to both sides of said casing oppositely in line with each other, piston means slidably mounted in each of said cylinder means defining a space between one side of the piston means and said cylinder head means, rod means connected at one end thereof to said piston means whereby said piston means and said rod means in said one pair of cylinder means linearly reciprocating as one unit, crank means having at least one crank pin corresponding to the number of pairs of said cylinders at a crank radius 1, means rotatably connecting each said crank pin to said rod means, at least one eccentric collar means rotatably supported by said casing and having support means rotatably supporting said crank means at the same amount of eccentricity-1, means to rotate said crank and collar means at the same uniform angular velocity and in reverse directions with respect to each other to effect linear reciprocating motion of said rod means, balance weight means having a total mass m secured to said crank means on the opposite side of said crank pin at a distance R from its axis, and wherein both said balance weight means are determined in accordance with the formulas ml-'m R and (m+m +m )l=M Rf2 wherein m is the total reciprocating mass and m is the total rotating mass except for said masses m and m whereby unbalanced forces caused by reciprocating mass are balanced.

5. A reciprocating machine as defined in claim 4 wherein said means to rotate said crank means and said eccentric collar means comprises a first toothed gear secured to said crank means, a first and a second shaft rotatably supported by said casing and extending parallel to the axis of said crank means, an eccentric gear having the same number of teeth as said first gear and having said amount of eccentricity-l secured to first shaft, second gear means secured to said first shaft third gear means secured to said second shaft and meshing with said second gear means, and fourth gear means secured to at least one said eccentric collar means and having the same number of teeth as in said second gear means and meshing with said third gear means.

6. A reciprocating machine as defined in claim 4 wherein said means to rotate said crank means and the eccentric collar means comprises planet gear means having a pitch circle diameter 21 secured to said crank means, and internal gear means secured to said casing concentric to said eccentric collar means and having a pitch circle diameter 4! and meshing with said planet gear means.

7. A reciprocating machine as defined in claim 4 wherein said machine further comprises wall means secured to each of said cylinder means defining a further space between said casing and the other side of said piston means and slidably accommodating said rod means.

8. A reciprocating machine as defined in claim 7 wherein said cylinder means further comprises inlet means communicating with said further space, outlet means communicating with said first-mentioned space, scavenge means communicating between said both spaces, and ignition means communicating said first-mentioned space, whereby said reciprocating machine operates as a two-cycle precompression chamber scavenging internal combustion engine in which each said pair of cylinders operate at phase difference.

9. A reciprocating engine comprising: a cylinder; a piston mounted for reciprocal movement in said cylinder in response to fluid pressure differentials applied thereacross; means for applying fluid pressure differentials across said piston to effect reciprocal movement of said piston; a rotatably crank mechanism having a rotatably mounted crankshaft and a crank pin connected thereto at a distance I from the crankshaft axis; a connecting rod interconnecting said piston and said crank pin; rotatably support means having an axis of rotation parallel to and a distance I from said crankshaft axis supporting said crank mechanism for rotation; means for effecting rotation of said crank mechanism and said support means at the same angular velocity but in opposite directions in response to reciprocal movement of said piston; a first balance weight having a total mess m connected to said crank mechanism at a distance R from said crank pin effective to balance said engine during rotation of said crankshaft; a second balance weight having a total mass m: connected to said support means at a distance R from said crank shaft axis; and wherein both said balance weights are determined in accordance with the formulas ml=m R and(m+m +m l=m R wherein m is the total reciprocating mass and m is the total rotating mass exclusive of said balance weights; whereby unbalanced forces caused by said reciprocating mass are balanced.

Claims

1. A balanced reciprocating machine comprising: a casing; means defining at least one enclosed cylinder secured to said casing; a piston slidably mounted in said cylinder and dividing said cylinder into two working spaces; means for alternately supplying and exhausting pressurized fluid into and out of each of said two working spaces to effect reciprocation of said piston; a connecting rod pivotally connected at one end thereof to said piston; crank means including a crank pin connected to the other end of said connecting rod at a crank radius l; collar means eccentrically and rotatably supported by said casing and having support means rotatably supporting said crank means at the same amount of eccentricity-l; means to rotate said collar means and said crank means at the same uniform angular velocity and in reverse directions with respect to each other to effect linear reciprocating motion of said connecting rod; a first balance weight having a total mass m1 secured to said crank means on the opposite side of said crank pin at a distance R1 from its axis; a second balance weight having a total mass m2 secured to said collar means on the opposite side of said support means at a distance R2 from its axis; and wherein both said balance weights are determined in accordance with the formulas ml m1R1 and (m+m1+m3)l m2 R2, wherein m is the total reciprocating mass and m3 is the total rotating mass exclusive of said balance weights; whereby unbalanced forces caused by said reciprocating mass are balanced.

4. A perfectly balanced reciprocating machine comprising a casing, at least one pair of cylinder means having cylinder head means secured to the casing, each pair of said cylinder means being secured to both sides of said casing oppositely in line with each other, piston means slidably mounted in each of said cylinder means defining a space between one side of the piston means and said cylinder head means, rod means connected at one end therEof to said piston means whereby said piston means and said rod means in said one pair of cylinder means linearly reciprocating as one unit, crank means having at least one crank pin corresponding to the number of pairs of said cylinders at a crank radius l, means rotatably connecting each said crank pin to said rod means, at least one eccentric collar means rotatably supported by said casing and having support means rotatably supporting said crank means at the same amount of eccentricity-l, means to rotate said crank and collar means at the same uniform angular velocity and in reverse directions with respect to each other to effect linear reciprocating motion of said rod means, balance weight means having a total mass m1, secured to said crank means on the opposite side of said crank pin at a distance R1 from its axis, and wherein both said balance weight means are determined in accordance with the formulas ml m1 R1 and (m+m1+m3)l M2R2, wherein m is the total reciprocating mass and m3 is the total rotating mass except for said masses m1 and m2, whereby unbalanced forces caused by reciprocating mass are balanced.

6. A reciprocating machine as defined in claim 4 wherein said means to rotate said crank means and the eccentric collar means comprises planet gear means having a pitch circle diameter 2l secured to said crank means, and internal gear means secured to said casing concentric to said eccentric collar means and having a pitch circle diameter 4l and meshing with said planet gear means.

8. A reciprocating machine as defined in claim 7 wherein said cylinder means further comprises inlet means communicating with said further space, outlet means communicating with said first-mentioned space, scavenge means communicating between said both spaces, and ignition means communicating said first-mentioned space, whereby said reciprocating machine operates as a two-cycle precompression chamber scavenging internal combustion engine in which each said pair of cylinders operate at 180* phase difference.

9. A reciprocating engine comprising: a cylinder; a piston mounted for reciprocal movement in said cylinder in response to fluid pressure differentials applied thereacross; means for applying fluid pressure differentials across said piston to effect reciprocal movement of said piston; a rotatably crank mechanism having a rotatably mounted crankshaft and a crank pin connected thereto at a distance l from the crankshaft axis; a connecting rod interconnecting said piston and said crank pin; rotatably support means having an axis of rotation parallel to and a distance l from said crankshaft axis supporting said crank mechanism for rotation; means for effecting rotation of said crank mechanism and said support means at the same angular velocity but in opposite directions in response to reciprocal movement of saId piston; a first balance weight having a total mess m1 connected to said crank mechanism at a distance R1 from said crank pin effective to balance said engine during rotation of said crankshaft; a second balance weight having a total mass m2 connected to said support means at a distance R2 from said crank shaft axis; and wherein both said balance weights are determined in accordance with the formulas ml m1R1 and (m+m1+m3)lm2R2, wherein m is the total reciprocating mass and m3 is the total rotating mass exclusive of said balance weights; whereby unbalanced forces caused by said reciprocating mass are balanced.