# US 8,783,224 B2 · Crankshaftless internal combustion engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,783,224 B2 - Document ID: US8783224B2 - Status: Granted - Kind: B2 - Application number: 13/528,408 - Filed: 2012-06-20 - Published: 2013-05-30 - Granted: 2014-07-22 - Earliest claimed: 2011-11-30 - Assignees: Hyundai Motor Company - Applicants: Wonjin Jo; Hyunjun Hong; Youngjic Kim; Kimin Park; Jerok Chun - Inventors: Wonjin Jo; Hyunjun Hong; Youngjic Kim; Kimin Park; Jerok Chun - Web page: https://patentgrep.com/patent/US8783224B2 ## CPC - F02D 15/02: by alteration or displacement of piston stroke - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) ## Abstract Included may be a crankshaftless internal combustion engine, including a power shaft unit in which a transferring path of a power system may be selected depending on a deactivated state and an activated state of a cylinder, a cylinder separator separating a power system of the deactivated cylinder from the power shaft unit by control of an ECU operated by a deactivated cylinder and an activated cylinder, and a compression changing unit varying a compression ratio of the activated cylinder in multistage. ## Claims ### Claim 1 A crankshaftless internal combustion engine, comprising: an engine block having a plurality of cylinders each having a reciprocating power system and controlled in a deactivated state and an activated state, a cylinder head including a valve system for exhausting air as well as supplying fuel required in each cylinder, and an oil pan provided below the cylinder head; a power shaft unit converting a power generated from a power system of an activated cylinder into an engine output and transferring the engine output to a transmission without transferring the engine output to a power system of a deactivated cylinder; a cylinder separator controlled by an ECU operating the plurality of cylinders as the deactivated cylinder and the activated cylinder and controlled by the ECU to separate the power system of the deactivated cylinder from the power shaft unit; and a compression changing unit controlled by the ECU so as to vary a compression ratio of the activated cylinder in multistage. ### Claim 2 (depends on 1) The crankshaftless internal combustion engine as defined in claim 1, wherein the power systems of the activated and deactivated cylinders include: a piston reciprocating in a combustion chamber of each cylinder so as to form a 4-stroke cycle; a connecting rod connected to the piston and reciprocating together with the piston, wherein the connecting rod has a thread formed on an outer peripheral surface; and a gear rod having a groove of thread to be engaged with the thread of the connecting rod, wherein the gear rod is engaged to the power shaft unit to rotate the power shaft unit while moving together with the connecting rod. ### Claim 3 (depends on 2) The crankshaftless internal combustion engine as defined in claim 2, wherein the gear rod includes: a pair of first and second fixation bosses formed at both sides thereof, and first and second intergears rotatably coupled to the first and second fixation bosses respectively, wherein the first and second intergears are meshed with inter gears formed in the engine block, wherein a vertical reciprocating movement of the gear rod is guided by the pair of first and second fixation bosses which engage with the respective first and second intergears that free rotates in the engine block, and wherein a gear is formed on the gear rod on different portions where the pair of first and second fixation bosses are not formed. ### Claim 4 (depends on 3) The crankshaftless internal combustion engine as defined in claim 3, wherein the power shaft unit includes: a main power shaft converting a power converted by the gear rod moving together with the connecting rod of the activated cylinder into the engine output transferred to the transmission; and a sub power shaft preventing the power of the main power shaft from being transferred to the gear rod moving together with the connecting rod of the deactivated cylinder in association with the cylinder separator, while transferring the power converted by using the gear rod moving together with the connecting rod of the activated cylinder to the main power shaft. ### Claim 5 (depends on 4) The crankshaftless internal combustion engine as defined in claim 4, wherein the main power shaft and the sub power shaft are arranged perpendicularly to the connecting rod and a rotation of the main power shaft or the sub power shaft is generated in a unidirectional stroke of the connecting rod in a reciprocating stroke thereof. ### Claim 6 (depends on 5) The crankshaftless internal combustion engine as defined in claim 5, wherein the power shaft unit includes: first semi gears formed to the main power shaft and second semi gears formed to the sub power shaft, the first and second semi gears being alternatively engaged with a gear of the gear rod. ### Claim 7 (depends on 6) The crankshaftless internal combustion engine as defined in claim 6, wherein the first and second semi gears have half portion thereof formed with a plurality of gear tooth and rotate with the same phase angle. ### Claim 8 (depends on 4) The crankshaftless internal combustion engine as defined in claim 4, wherein a switching gear is engaged to both an input gear connected to the sub power shaft and an output gear connected to the main power shaft. ### Claim 9 (depends on 4) The crankshaftless internal combustion engine as defined in claim 4, wherein the main power shaft has a flywheel at a connection portion of the transmission and an accessory configured by a timing gear together with a driving pulley of an electronic apparatus at an opposite side to the connection portion of the transmission. ### Claim 10 (depends on 1) The crankshaftless internal combustion engine as defined in claim 1, wherein the cylinder separator includes: a moving fork of which a direction is switched according to a switching power unit having a relay switched by control by the ECU; and a moving gear slidably mounted on the sub power shaft and engaged to the moving fork so as to move on the sub power shaft according to an operation of the moving fork, wherein at least one of the second semi gears are mounted to the moving gear, and wherein the moving gear adds the engine output to the main power shaft of the power shaft unit transferring the engine output to the transmission, and wherein according to the operation of the moving fork, the moving fork moves the at least one second semi gear along the sub power shaft. ### Claim 11 (depends on 10) The crankshaftless internal combustion engine as defined in claim 10, wherein a pair of moving gears is configured to move at least two semi gears by one-time movement of a pair of moving forks. ### Claim 12 (depends on 10) The crankshaftless internal combustion engine as defined in claim 10, wherein the moving fork has a fork structure engaged with the at least one second semi gear and the moving gear to which the at least one second semi gear is mounted is a hub including a protruding portion that engages with the moving fork. ### Claim 13 (depends on 12) The crankshaftless internal combustion engine as defined in claim 12, wherein a pair of hubs are configured to move at least two semi gears by one-time movement and a pair of moving forks are configured to move the pair of hubs. ### Claim 14 (depends on 12) The crankshaftless internal combustion engine as defined in claim 12, wherein the hub is spline-coupled to the sub power shaft to move the at least one second semi gear. ### Claim 15 (depends on 1) The crankshaftless internal combustion engine as defined in claim 1, wherein the compression changing unit includes: a switching power unit having a relay switched by control of the ECU; a rack bar engaged to the switching power unit and linearly moving by a switching operation of the switching power unit; and a pinion fixed to the connecting rod and engaged to the rack bar, wherein the piston moves vertically while the pinion rotates the connecting rod by linear movement of the rack bar as to move the gear rod to vary a relative distance between the power shaft unit and the piston. ### Claim 16 (depends on 15) The crankshaftless internal combustion engine as defined in claim 15, wherein the pinion is integrally provided at an end portion of the connecting rod. ### Claim 17 (depends on 15) The crankshaftless internal combustion engine as defined in claim 15, wherein the compression changing unit is installed in the oil pan.