Engine valve timing device

Abstract

The utility model relates to mechanical engineering, specifically to valve timing mechanisms for machines or engines. The technical result is achieved in that the engine variable valve timing device comprises a kinematic connection with the crankshaft and a kinematic connection with the camshaft with a planetary gear mechanism consisting of a sun gear, a ring gear, and a planet carrier with satellites. The sun gear, ring gear, and planet carrier are configured to interchangeably distribute the functions of the driving, driven, and control links, wherein the driving link is kinematically connected to the crankshaft, and the driven link is kinematically connected to the camshaft. The control link is a free link kinematically connected to a control drive, providing controlled angular movement of the control link to shift the phase of the output shaft and fix its angular position.The claimed utility model improves the accuracy of valve timing control under dynamic loads of the engine gear drive. 8 clauses, 1 fig.

Description

[0001] The utility model relates to mechanical engineering, namely to distribution mechanisms for machines or engines.

[0002] A DEVICE FOR ADJUSTING PHASES FOR A CAMSHAFT is known from the prior art according to patent JP 2008101609 A with a publication date of 01.05.2008, comprising a housing, a differential bevel gear placed between the leading element of the drive and the camshaft, including a system of satellites and an electric actuator designed to change the relative angular position of the differential links for the purpose of adjusting the valve timing.

[0003] A disadvantage of this analog is the insufficient accuracy of valve timing control under high dynamic loads on the engine's gear drive. This is due to the fact that the control signal transmission circuit used in this analog lacks sufficient mechanical rigidity and the ability to firmly lock the selected position under the influence of variable torques occurring on the camshaft. The absence of a high-load-capacity mechanism in the drive, such as a nut-and-screw transmission, leads to inertial errors and phase "floating" during engine operation in transient conditions or under significant forces on the timing gear.

[0004] Also a close analogue is the DEVICE FOR VARIING THE CAMERA TIMING PHASES according to patent EP 0539425 A1 with the publication date of 04 / 28 / 1993, containing a camshaft, a mechanism for changing the instantaneous phase of the camshaft relative to the phase of the crankshaft, acting on the cams to change the moments of their opening and closing, and a control system that ensures the operation of the mechanism according to a given program.

[0005] A disadvantage of this analogue is the insufficient accuracy of valve timing control under high dynamic loads on the engine's gear drive. This is due to the fact that the design uses mechanisms that do not provide rigid mechanical fixation of the set angle under sharp fluctuations in camshaft torque. The absence of a precision actuator with a rigid connection, such as a nut-and-screw pair, in combination with a servo drive, makes it impossible to accurately maintain the phase under the high loads typical of powerful industrial engines, and positioning accuracy is dependent on inertial factors and backlash in the kinematic control circuits.

[0006] The closest analogue (prototype) is the VALVE PHASE CONTROL DEVICE according to patent CN 102486106 B with the publication date of 04 / 16 / 2014, containing a housing, a differential mechanism with a leading bevel gear kinematically connected to the drive from the crankshaft, a driven bevel gear connected to the camshaft, and an adjustment unit designed to mechanically change the relative angular position of the shafts through action on the intermediate elements of the differential.

[0007] The main technical issue with the prototype is the insufficient accuracy of valve timing control under high dynamic loads on the engine's gear drive. This is due to the design of the control unit in the prototype not providing rigid mechanical locking and precise fixation of the intermediate differential links under the influence of significant variable torques typical of the timing drives of high-power diesel engines. The absence of a power actuator in the kinematic control circuit, in the form of a nut-and-screw transmission coupled with a servomotor, leads to micro-play and inertial phase deviations under load, which reduces the stability of the valve timing mechanism and limits the device's suitability for use in highly loaded gear drives of heavy equipment.

[0008] The technical problem solved by the claimed utility model is the elimination of the shortcomings of analogues and the prototype.

[0009] The objective of the claimed utility model is to create a device for a gas distribution mechanism with the ability to precisely position the phase shift angle of the engine shafts, achieved by changing the angular position of the control part of the planetary mechanism and the control drive.

[0010] The technical result of the claimed utility model consists in increasing the accuracy of regulating the valve timing under conditions of dynamic loads of the engine gear drive.

[0011] The specified technical result is achieved in that the device for changing the valve timing of the engine, containing a kinematic connection with the crankshaft and a kinematic connection with the camshaft with a planetary transmission mechanism consisting of a sun gear, a ring gear and a planet carrier with satellites, wherein the sun gear, the ring gear and the planet carrier are made with the possibility of interchangeable distribution of the functions of the driving, driven and control links, wherein the driving link is connected via a kinematic connection with the crankshaft, and the driven link is connected via a kinematic connection with the camshaft, the control link is a free link, kinematically connected with the control drive, providing controlled angular movement of the control link for shifting the phase of the output shaft and fixing its angular position.

[0012] Specifically, the driving link is the sun gear, the control link is the planet carrier, and the driven link is the ring gear.

[0013] Specifically, the driving link is the sun gear, the control link is the ring gear, and the driven link is the planet carrier.

[0014] Specifically, the leading link is the planet carrier, the controlling link is the sun gear, and the driven link is the ring gear.

[0015] Specifically, the leading link is the planet carrier, the controlling link is the ring gear, and the driven link is the sun gear.

[0016] Specifically, the driving link is the ring gear, the control link is the planet carrier, and the driven link is the sun gear.

[0017] Specifically, the driving link is the ring gear, the control link is the sun gear, and the driven link is the planet carrier.

[0018] In particular, the control drive is designed with the ability to maintain a given position of the control link when exposed to dynamic loads.

[0019] The proposed utility model is illustrated by a drawing.

[0020] Fig. 1 shows a diagram of the engine valve timing device.

[0021] The figure shows: 1 - kinematic connection with the crankshaft, 2 - sun gear, 3 - satellites, 4 - carrier, 5 - control drive, 6 - ring gear, 7 - kinematic connection with the camshaft.

[0022] A device for changing the valve timing of an engine, comprising a kinematic connection with a crankshaft (1) and a kinematic connection with a camshaft (7) with a planetary transmission mechanism consisting of a sun gear (2), a ring gear (6) and a carrier (4) with satellites (3), wherein the sun gear (2), the ring gear (6) and the carrier (4) are made with the possibility of interchangeable distribution of the functions of the driving, driven and control links, wherein the driving link is connected via a kinematic connection with the crankshaft (1), and the driven link is connected via a kinematic connection with the camshaft (7), the control link is a free link, kinematically connected with the control drive (5), providing controlled angular movement of the control link for shifting the phase of the output shaft and fixing its angular position.

[0023] The achievement of the stated technical result, expressed in the increase in the accuracy of regulation of the valve timing phases under conditions of dynamic loads of the engine gear drive, is ensured through a direct cause-and-effect relationship between the set of essential design features of the device.

[0024] The presence of a rigid kinematic connection to the crankshaft (1) and a kinematic connection to the camshaft (7) with a planetary gear mechanism completely eliminates elastic deformations and stretching typical of chain or belt drives. This rigid connection guarantees instant and synchronous transmission of angular position without inertial distortion, providing a reliable basis for stable system operation during sudden changes in engine speed.

[0025] The use of a planetary gear mechanism consisting of a sun gear (2), ring gear (6), and planet carrier (4) with satellites (3) provides a significant advantage in the mechanism's load capacity. The multiple-pair gear engagement, in which torque is distributed simultaneously through several satellites (3), minimizes contact stress and the overall kinematic backlash of the system. This design solution prevents self-oscillations and so-called phase "floating" under the influence of alternating pulses arising from overcoming the forces of the valve springs.

[0026] The implemented capability of interchangeably distributing the functions of the driving, driven, and control links between the sun gear (2), ring gear (6), and planet carrier (4) provides exceptional flexibility in adjusting the kinematic scheme. This variability allows for the selection of the optimal leverage and internal gear ratio, which minimizes the impact of dynamic reverse shocks from the camshaft on the control link. The kinematic connection with the crankshaft (1) for the driving link, and the kinematic connection with the camshaft (7) for the driven link, forms a continuous power circuit capable of reliably maintaining the basic phase angle under any conditions.

[0027] The design of the control link as a free link, kinematically connected exclusively to the control drive (5), allows it to be used as a precision instrument for introducing phase correction without interrupting the main power flow. The design of the control drive (5) with controlled angular movement and rigid fixation of the control link's angular position gives the system the properties of a mechanical lock. The control drive (5) perceives and effectively absorbs the reverse dynamic loads from the valve mechanism, completely eliminating spontaneous angular displacement of the free link around its axis.

[0028] Thus, the integrated interaction of the multi-pair engagement of the planetary row with the precision-fixed control drive (5) through the kinematic connection with the crankshaft (1) and the kinematic connection with the camshaft (7) guarantees strict compliance of the actual valve timing angle with the specified parameters, which together proves the actual achievement of the declared increase in accuracy.

[0029] The engine variable valve timing device operates as follows: during engine operation, the torque from the crankshaft is transmitted through a kinematic connection with the crankshaft (1) and causes the drive link of the planetary gear mechanism to rotate.

[0030] Depending on the selected interchangeable distribution of functions, the sun gear (2), ring gear (6), or planet carrier (4) with satellites (3) acts as the driving link. Rotational motion is transmitted from the driving link through the toothed engagement of the satellites (3) to the driven link, which, through a kinematic connection with the camshaft (7), transmits torque, ensuring synchronous rotation of the camshaft.

[0031] In steady-state operation, when phase shift is not required, the control link, which is the free link of the planetary gear, is rigidly held in a predetermined angular position around its axis by the control drive (5). The kinematic connection between the control drive (5) and the control link, which can self-braking or lock into place, creates a mechanical locking effect.

[0032] The reverse dynamic impulses and alternating loads transmitted from the camshaft cams during the operation of the valve mechanism are absorbed by the control mechanism and cannot forcibly rotate the control link, which guarantees the absolute stability of the current phase.

[0033] When the valve timing needs to be adjusted, the control drive (5) begins moving based on a signal from the engine management system. This movement is converted through a kinematic linkage into controlled angular displacement of the control link around its axis.

[0034] Forced rotation of the control link (sun gear, ring gear or planet carrier, depending on the configuration) upsets the static balance of the planetary gear set and forces the satellites (3) to perform additional rolling.

[0035] This kinematic disturbance introduces an angular correction into the movement of the driven link, which leads to a smooth and precise phase shift of the camshaft relative to the crankshaft.

[0036] The phase shift process occurs without interrupting the power flow transmitted to the camshaft. The control actuator (5) can be equipped with a feedback sensor to record the position angle, but can also be used without a sensor, shifting the control link from one position to another.

[0037] The presence of a feedback sensor allows the control drive (5) to dose the control action with high resolution and instantly compensate for any possible errors, ensuring the declared increase in the accuracy of valve timing control under conditions of intense dynamic loads.

[0038] In the first example of the engine variable valve timing device, the engine crankshaft is connected via a kinematic linkage with the crankshaft (1) to the sun gear (2) of the planetary gear mechanism, which functions as the driving link. The ring gear (6), which functions as the driven link, is connected to the engine camshaft via a kinematic linkage with the camshaft (7).

[0039] The carrier (4) with the satellites (3) mounted on it functions as a free control link, with the satellites (3) being in constant toothed mesh simultaneously with the sun gear (2) and the ring gear (6). The control drive (5) is kinematically connected to the control link – the carrier (4), ensuring its movement and reliable retention in a given position.

[0040] When the engine is operating in steady state, torque is transmitted from the crankshaft via the crankshaft linkage (1) to the sun gear (2), which rotates the planet gears (3), which transmit torque to the ring gear (6) and then via the camshaft linkage (7) to the camshaft. At this time, the planet carrier (4) is held motionless by the control drive (5), completely eliminating spontaneous displacement of the control link under dynamic loads.

[0041] To shift the valve timing, the control drive (5) causes a forced angular rotation of the planet carrier (4) around its axis. The rotation of the planet carrier (4) causes the planet gears (3) to orbit the rotating sun gear (2), which introduces a kinematic angular correction into the movement of the ring gear (6), ensuring precise phase shift.

[0042] In the second example of the engine variable valve timing device, the planet carrier (4) is used as the driving element. In this configuration, the engine crankshaft is connected to the planet carrier (4) of the planetary gear mechanism via a kinematic link with the crankshaft (1). Planet gears (3) are mounted on the planet carrier (4) axes and are in constant mesh with the ring gear (6) and sun gear (2).

[0043] The ring gear (6) functions as the driven link and is rigidly connected to the camshaft (7) via a kinematic linkage. The sun gear (2) in this example serves as the free control link. The control drive (5) is kinematically connected to the control link—the sun gear (2), enabling its movement and securely holding it in a given position.

[0044] When the engine is running in steady state, torque is transmitted from the crankshaft via the crankshaft linkage (1) to the planet carrier (4). Since the sun gear (2) is rigidly locked by the control drive (5), the planet gears (3) are forced to roll around the stationary sun gear (2). This movement is transmitted to the ring gear (6) and, accordingly, via the kinematic linkage with the camshaft (7), rotates the camshaft at a set frequency. The ability of the control drive (5) to lock the position ensures that the variable torques generated on the sun gear (2) due to the resistance of the valve springs do not lead to phase deviation.

[0045] Valve timing adjustment is performed by activating the control actuator (5). The movement of the control actuator (5) is transmitted via a kinematic linkage to the sun gear (2), causing its forced angular rotation. This rotation of the sun gear (2) changes the orbital trajectory of the planet gears (3) relative to the planet carrier (4), which instantly introduces an angular displacement into the movement of the ring gear (6). As a result, the camshaft receives an additional angular impulse relative to the crankshaft, ensuring precise adjustment of the valve opening and closing timing in accordance with the commands of the control system.

[0046] In the third example of the engine variable valve timing device, the engine crankshaft is connected via a kinematic linkage with the crankshaft (1) to the sun gear (2) of the planetary gear mechanism, which functions as the driving link. The planet carrier (4) with the planetary gears (3) mounted on it functions as the driven link and is rigidly connected via a kinematic linkage with the camshaft (7) of the engine.

[0047] The crown gear (6) in this configuration acts as a free control link, constantly engaged with the planet gears (3) of the carrier (4). The control drive (5) is kinematically connected to the control link—the crown gear (6), enabling its movement and securely holding it in a given position.

[0048] When the crankshaft rotates in steady state, torque is transmitted through the kinematic linkage with the crankshaft (1) to the sun gear (2), which drives the planet gears (3). Since the ring gear (6) is rigidly held in a predetermined angular position by the control drive (5), the planet gears (3) are forced to roll along the inner surface of the stationary ring gear (6). This movement is transmitted to the planet carrier (4) and through the kinematic linkage with the camshaft (7), ensuring synchronous rotation of the camshaft. The ability of the control drive (5) to reliably lock ensures effective damping of feedback dynamic impulses, eliminating spontaneous phase angle fluctuations.

[0049] To forcefully change the valve timing, the control system activates the control drive (5). The movement of the control drive (5) is converted via a kinematic linkage into a controlled angular rotation of the ring gear (6) around its axis. This rotation of the ring gear (6) forcibly shifts the orbital position of the rolling satellites (3), resulting in an instantaneous, precise angular shift of the planet carrier (4) and camshaft relative to the sun gear (2) and crankshaft. This allows for precise control of the rotation angle of the ring gear (6) and ensures accurate phasing at all engine operating conditions.

[0050] In the fourth embodiment of the engine variable valve timing device, the crankshaft is connected via a kinematic link with the crankshaft (1) to the planetary gear carrier (4), which functions as the driving link. The sun gear (2), which functions as the driven link, is rigidly connected via a kinematic link with the camshaft (7). The ring gear (6) in this configuration acts as a control free link, which is in constant mesh with the satellites (3), mounted on the axes of the rotating planet carrier (4). The control drive (5) is kinematically connected to the control link - the ring gear (6), ensuring its movement and reliable retention in a given position.

[0051] When the engine is running in steady state, the torque from the crankshaft is transmitted through the kinematic link with the crankshaft (1) to the planet carrier (4), which moves the planet gears (3) in an orbit. Since the ring gear (6) is rigidly held from turning by the control drive (5), the planet gears (3) roll along its internal toothed rim. This causes the planet gears (3) to rotate around their axes and transmit torque to the central sun gear (2), ensuring rotation of the camshaft through the kinematic link with the camshaft (7) and synchronous operation of the system. The ability of the control drive (5) to reliably lock the ring gear (6), preventing dynamic impulses from the valve mechanism from disrupting the specified phasing.

[0052] To shift the valve timing, the control system sends a signal, and the control actuator (5) begins to move. This movement, via a kinematic linkage, causes a forced angular rotation of the ring gear (6) around its axis. This shift of the ring gear (6) changes the kinematics of the rolling of the planet gears (3) located on the rotating planet carrier (4), which introduces a precise angular correction to the rotation of the driven sun gear (2). This results in a smooth phase shift of the camshaft relative to the crankshaft, allowing for precise adjustment of engine performance depending on the current load.

[0053] In the fifth embodiment of the engine variable valve timing device, the crankshaft is kinematically connected to the ring gear (6) of the planetary gear mechanism via a crankshaft (1) connection, which functions as the driving link. The sun gear (2), which functions as the driven link, is connected to the camshaft via a kinematic connection with the camshaft (7). The planet carrier (4) with the satellites (3) mounted on it functions as a control free link, wherein the satellites (3) are in constant toothed mesh simultaneously with the ring gear (6) and the sun gear (2). The control drive (5) is kinematically connected to the control link - the planet carrier (4), executing its movement and reliably holding it in a given position.

[0054] When the engine is operating in steady state, torque is transmitted from the crankshaft via the crankshaft linkage (1) to the ring gear (6), which, through its internal engagement, rotates the planet gears (3). Since the planet carrier (4) is held motionless by the control drive (5), the planet gears (3) rotate only around their axes, transmitting torque to the central sun gear (2) and the camshaft. The control drive (5)'s secure locking capability completely eliminates spontaneous displacement of the control link under variable loads, reliably recording the current phase position.

[0055] To shift the valve timing, the control system activates the control actuator (5), which begins to move. The movement of the control actuator (5), via a kinematic linkage, causes a forced angular rotation of the planet carrier (4) around its axis. This rotation causes the axes of the planet gears (3) to perform an additional orbital movement, which kinematically combines with the primary rotation and introduces a precise angular correction to the movement of the driven sun gear (2). This results in a precise phase shift of the camshaft relative to the crankshaft, allowing for precise adjustment of engine operating parameters under load.

[0056] In the sixth embodiment of the engine variable valve timing device, the crankshaft is kinematically connected to the crankshaft (1) and the ring gear (6) of the planetary gear mechanism, which functions as the driving link. The planet carrier (4) with the satellites (3) mounted on it functions as the driven link and is connected to the camshaft via a kinematic link with the camshaft (7). The sun gear (2) in this configuration acts as a control free link, constantly meshing with the satellites (3) of the planet carrier (4). The control drive (5) is kinematically connected to the control link - the sun gear (2), ensuring its movement and reliable retention in a given position.

[0057] In steady-state engine operation, the torque from the crankshaft is transmitted to the drive ring gear (6) via the kinematic linkage with the crankshaft (1). As the ring gear (6) rotates, it sets the planet gears (3) in motion via the internal toothed ring. Since the sun gear (2) is rigidly locked from turning by the control drive (5), the planet gears (3) are forced to roll around the stationary sun gear (2), dragging the planet carrier (4) along with them. This orbital motion is transmitted to the camshaft via the kinematic linkage with the camshaft (7), ensuring its synchronous rotation. The ability of the control drive (5) to reliably lock the sun gear (2), completely eliminating spontaneous displacement of the control link due to the impact of reverse dynamic impacts from the valve mechanism.

[0058] To shift the valve timing, the control system activates the control actuator (5) and begins moving. This movement, via a kinematic linkage, smoothly and controllably rotates the control sun gear (2) around its axis. The forced angular displacement of the sun gear (2) changes the reference point of the planet gears (3), which instantly introduces an angular correction to the rotation of the driven planet carrier (4). As a result, the camshaft receives a precise angular shift relative to the crankshaft, allowing for precise adjustment of the valve timing to the current engine load.

Claims

1. A device for changing the valve timing of an engine, comprising a kinematic connection with a crankshaft and a kinematic connection with a camshaft with a planetary transmission mechanism consisting of a sun gear, a ring gear and a planet carrier with satellites, wherein the sun gear, the ring gear and the planet carrier are designed with the possibility of interchangeably distributing the functions of the driving, driven and control links, wherein the driving link is connected via a kinematic connection with the crankshaft, and the driven link is connected via a kinematic connection with the camshaft, characterized in that the control link is a free link, kinematically connected with a control drive, providing controlled angular movement of the control link for shifting the phase of the output shaft and fixing its angular position.

2. The device according to paragraph 1, characterized in that the driving link is a sun gear, the control link is a planet carrier with satellites, and the driven link is a crown gear.

3. The device according to paragraph 1, characterized in that the driving link is a sun gear, the control link is a crown gear, and the driven link is a planet carrier with satellites.

4. The device according to paragraph 1, characterized in that the driving link is a planet carrier with satellites, the control link is a sun gear, and the driven link is a crown gear.

5. The device according to paragraph 1, characterized in that the driving link is a planet carrier with satellites, the control link is a crown gear, and the driven link is a sun gear.

6. The device according to paragraph 1, characterized in that the driving link is a crown gear, the control link is a planet carrier with satellites, and the driven link is a sun gear.

7. The device according to claim 1, characterized in that the driving link is a crown gear, the control link is a sun gear, and the driven link is a planet carrier with satellites.

8. The device according to paragraph 1, characterized in that the kinematic connection of the control drive with the control link is designed with the possibility of self-braking or mechanical locking to prevent spontaneous rotation of the control link under the action of loads from the camshaft.

9. The device according to claim 1, characterized in that the control drive is designed with the ability to maintain a given position of the control link when exposed to dynamic loads.

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