System for synchronous switching between two rockers

Abstract

In one embodiment, a system for synchronization is provided. The system comprises: a switchable first rocker arm; the second rocker arm can be switched; a first switching mechanism disposed in the first rocker arm and configured to enable controlled switching of the first rocker arm by moving between a first position and a second position; and a second switching mechanism disposed in the second rocker arm and configured to controllably switch the second rocker arm by moving between a third position and a fourth position. Switching of the first rocker arm and switching of the second rocker arm are effected by a single actuation source and their switching is controlled and performed in sequence.

Description

[0001] Cross-reference to related applications

[0002] The present disclosure is based upon and claims the benefit of U.S. Provisional Application No. 63 / 326,946 filed on April 4, 2022 and U.S. Provisional Application No. 63 / 366,965 filed on June 24, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to valve actuation systems and, more particularly, to a system for synchronized switching between two rocker arms in a valvetrain assembly. Background Art

[0004] Valve actuation systems known in the art are commonly used in internal combustion engines. Some valve train designs may be configured with a variable valve lift function, in which the height of the valve opening is changed in an attempt to improve engine performance, fuel economy or exhaust emissions. Some variable valve lift functions require switching of a first rocker arm and a second rocker arm to achieve the desired function. For example, by switching the rocker arm, it can be selected whether to allow the cam to actuate the associated valve. Typically, it may be necessary to control the first rocker arm and the second rocker arm to switch at the appropriate time. Due to the valve lift sequence, in order to ensure a safe switching event, in a conventional valve actuation system, it may be necessary to set up a central unit and set up independent control systems for the two rocker arms to synchronize the electronic control signals to achieve the correct switching sequence. This increases the size and complexity of the entire system.

[0005] Therefore, there is a need to implement a system for synchronized switching between two rocker arms that uses a simplified mechanism to control the appropriate switching. Summary of the invention

[0006] The present disclosure proposes a system for synchronization, which helps to reduce the size and complexity of the valve actuation system and ensures the correct switching sequence of the rocker arms by mechanically implementing the switching of two rocker arms using a single control source.

[0007] In one embodiment, a system for synchronization includes: a first rocker arm configured to switch between a first mode and a second mode; a second rocker arm configured to switch between a third mode and a fourth mode; a first switching mechanism arranged in the first rocker arm and configured to controllably switch the first rocker arm between the first mode and the second mode by moving between a first position and a second position; and a second switching mechanism arranged in the second rocker arm and configured to controllably switch the second rocker arm between the third mode and the fourth mode by moving between a third position and a fourth position. The movement of the first switching mechanism and the movement of the second switching mechanism are actuated by a single actuation source. In addition, the movement of the first switching mechanism between the first position and the second position causes the second switching mechanism to move between the third position and the fourth position, thereby sequentially performing the switching of the first rocker arm and the switching of the second rocker arm.

[0008] In a specific embodiment, the single actuation source is a fluid control valve.

[0009] In a specific embodiment, the first rocker arm and the second rocker arm are arranged closely to each other.

[0010] In a specific embodiment, at least a portion of the first switching mechanism and at least a portion of the second switching mechanism are configured to maintain physical contact with each other.

[0011] In particular embodiments, the system for synchronizing further includes a return spring coupled to the second switching mechanism and configured to bias both the first switching mechanism and the second switching mechanism.

[0012] In a specific embodiment, the first rocker arm includes a deactivation roller configured to be selectively locked by the first switching mechanism so that the first rocker arm is selectively switched between the first mode and the second mode.

[0013] In a specific embodiment, the second rocker arm includes a first fluid circuit and a second fluid circuit. In a specific embodiment, the second switching mechanism includes a slide valve. In a specific embodiment, the slide valve is configured to selectively enable or disable fluid communication between the first fluid circuit and the second fluid circuit of the second rocker arm, so that the second rocker arm selectively switches between the third mode and the fourth mode.

[0014] In a specific embodiment, the first switching mechanism includes a spool valve. In a specific embodiment, the first rocker arm includes a first fluid circuit and a second fluid circuit. In a specific embodiment, the spool valve is configured to selectively enable or disable fluid communication between the first fluid circuit and the second fluid circuit of the first rocker arm. In a specific embodiment, the second rocker arm includes a third fluid circuit configured to be hydraulically engaged with the second fluid circuit of the first rocker arm. In a specific embodiment, movement of the second switching mechanism is actuated by fluid supplied from the first fluid circuit through the second fluid circuit to the third fluid circuit, so that the second rocker arm switches between the third mode and the fourth mode.

[0015] In a specific embodiment, the system for synchronization further includes: a first return spring coupled to the first switching mechanism and configured to bias the first switching mechanism; and a second return spring coupled to the second switching mechanism and configured to bias the second switching mechanism.

[0016] In particular embodiments, the first rocker arm and the second rocker arm are biased against each other by one or more biasing springs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Embodiments according to the present disclosure will now be described with reference to the accompanying drawings, in which:

[0018] Figure 1 is an isometric partial view of an exemplary valve train system incorporating an embodiment of a synchronization system according to the present disclosure;

[0019] Figure 2 It shows Figure 1 An isometric partial view of a portion of a rear side of an exemplary valve train system in FIG.

[0020] Figure 3 yes Figure 1 A cross-sectional view of a synchronization system in which the position of the first switching mechanism and the position of the second switching mechanism are specifically shown when the synchronization system is in a driving mode;

[0021] Figure 4 yes Figure 1 A cross-sectional view of a synchronization system in which the position of the first switching mechanism and the position of the second switching mechanism are specifically shown when the synchronization system is in an engine braking mode;

[0022] Figure 5 yes Figure 1 A cross-sectional view of a synchronization system in which the position of the first switching mechanism and the position of the second switching mechanism are specifically shown when the first rocker arm is in full lift drive mode and the second rocker arm is deactivated;

[0023] Figure 6is a schematic cross-sectional illustration of another embodiment of a synchronization system according to the present disclosure;

[0024] Figure 7 It shows Figure 6 A schematic cross-sectional illustration of a first rocker arm of a synchronization system in , wherein the first rocker arm is in a first position; and

[0025] Figure 8 It shows Figure 6 Schematic cross-sectional illustration of a first rocker arm of a synchronization system in FIG. , wherein the first rocker arm is in a second position. DETAILED DESCRIPTION

[0026] Reference will now be made in detail to the examples shown in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to represent the same or similar parts. Directional references such as "upper", "lower", "right" and "left" are for ease of reference to the drawings.

[0027] Figure 1An embodiment of a synchronization system of the present disclosure is shown, which synchronization system is applicable to a valve train assembly 100. In a specific embodiment, the valve train assembly 100 may include a first rocker arm 102 and a second rocker arm 104, and the respective end portions of the first rocker arm and the second rocker arm may overlap on the first cam 106 and the second cam 108 of the camshaft in a manner known in the art. As shown, the first rocker arm 102 and the second rocker arm 104 are arranged closely to each other. In some embodiments, the first rocker arm 102 and the second rocker arm 104 may be brought into contact with each other to form an interface between the two rocker arms. In a specific embodiment, when used in conjunction with an internal combustion engine in the context of a rocker arm for performing an engine braking operation, the first rocker arm 102 may be, for example, a main exhaust rocker arm that can be used to selectively control the exhaust movement of the engine valve and is configured with a deactivation function, and the second rocker arm 104 may be an engine braking rocker arm that can be braked together with the engine. Accordingly, in this case, the first cam 106 coupled to the main exhaust rocker arm may be a main lift cam, while the second cam 108 coupled to the engine brake rocker arm may be an engine brake lift cam. Typically, a rocker arm configured to implement a so-called valve deactivation function (i.e., a selected valve combination can be systematically disabled to adjust engine efficiency) is provided with a deactivation roller 112, which in the illustrated example can be configured to operatively engage with the first cam 106 and can be controllably moved relative to the first rocker arm 102 to enable and / or disable the transmission of motion from the camshaft to the associated engine valve as desired. Specifically, as an example, in operation, the deactivation roller 112 can be locked (e.g., advantageously by a switching mechanism, the details of which will be further described below) to be in a fixed relationship with the first rocker arm 102 and prevented from moving relative to the first rocker arm, thereby forming a single unit with the first rocker arm 102, which can be lifted as a whole to allow the valve actuation motion supplied by the camshaft to be transmitted to the engine valve. Conversely, in the event that valve deactivation is desired, the deactivation roller 112 can be released from the locked position to an unlocked position in which the deactivation roller 112 is free to reciprocate relative to the first rocker arm 102 (e.g., in a vertical direction as shown) to such an extent that any rotational motion imparted by the first cam 106 is absorbed by the relative vertical movement between the deactivation roller 112 and the first rocker arm 102. This type of operating mode is also referred to as loss of motion, i.e., a "loss" of motion on a selected rocker arm, thereby disabling the associated engine valve. In this manner, by selectively controlling the deactivation roller 112 to switch between the locked position and the unlocked position, activation and deactivation of the valve can be performed accordingly.

[0028] Figure 2 Shows Figure 1, wherein the first rocker arm 102 is shown as being operatively coupled to a valve bridge 202 spanning a first valve (such as a main exhaust valve) and a second valve (such as a brake valve) so that both the first valve and the second valve can be actuated simultaneously via the first rocker arm 102. On the other hand, the second rocker arm 104 can extend through the valve bridge 202 and act directly on the second valve so that the second valve can be actuated separately. In a specific embodiment in which the second rocker arm 104 is used as an engine brake rocker arm, the second rocker arm 104 can be configured to selectively actuate the brake valve. To this end, for example, an engine brake capsule 110 is provided at one end of the second rocker arm 104 associated with the brake valve. As an example and not limitation, the engine brake capsule 110 can be configured to selectively translate between an extended position and a retracted position, in which the actuation of the brake valve by the second cam 108 via the second rocker arm 104 is enabled, and in which the actuation of the brake valve is disabled. In a specific embodiment, the engine brake capsule 110 can be hydraulically actuated. As an example, the second rocker arm 104 can be arranged with one or more fluid channels for supplying pressurized fluid to the engine brake capsule 110, thereby achieving switching of the engine brake capsule 110, which will be described in more detail below. Additionally or alternatively, the valve train assembly 100 can be provided with other suitable configurations and functions, which are obvious to those skilled in the art based on the specification, drawings and claims disclosed herein, and therefore the present disclosure will not be described in detail.

[0029] For a valve train assembly that uses two switchable rocker arms (such as the first rocker arm 102 and the second rocker arm 104 as described above), it may be necessary to synchronously switch the first rocker arm 102 and the second rocker arm 104 in order to provide the correct function as needed. For example, it may be beneficial to perform the synchronous switching of the two rocker arms through a single control source. In this way, compared with a conventional system that requires a central unit to be set up and an independent control mechanism to be set up for each of the two rocker arms to achieve synchronous switching (usually through an electrical control signal), the synchronous system according to the present disclosure that uses a single source to mechanically control the synchronous switching can save half of the control system, thereby greatly simplifying the entire system.

[0030] Furthermore, where the correct switching sequence and timing are critical, such as to facilitate increased rocker movement to achieve a 1.5 or 2-stroke engine braking mode, the synchronization system of the present disclosure can ensure that engine braking is enabled only after the main lift event of the main exhaust rocker is deactivated, thereby controlling the main event deactivation and engine braking activation to be staggered and not overlapped. The engine braking valve lift can be enabled while the valve main event used in the drive mode is deactivated. The main event lift of the main rocker can be deactivated, thereby avoiding excessive forces on the main rocker. Then, the engine braking can be enabled after the main rocker is deactivated.

[0031] Although specific embodiments of the present disclosure are described in the context of a rocker arm for operating an exhaust valve in an engine braking system (such as for use under 1.5 stroke decompression braking), it should be understood that the present disclosure is not limited to this. The synchronization system according to the present disclosure is also applicable to other types of rocker arms in a valve train assembly. For example, the present disclosure may be applicable to an intake rocker arm system including a first intake rocker arm and a second intake rocker arm. In this regard, the camshaft may be configured with a primary lift cam and a secondary lift cam. Alternatively or additionally, for example, the present disclosure may also be applicable to a valve train configured for early exhaust valve opening, delayed intake valve closing, or other variable valve lift configurations familiar to those skilled in the art.

[0032] Figure 3 Shown is the layout Figure 1 The synchronization system 300 of the present disclosure in the valve train assembly 100 in the embodiment of the present invention may provide some or all of the benefits described above. In a specific embodiment, a first switching mechanism 302 is provided, which may be used in combination with the deactivation roller 112 of the first rocker arm 102 to selectively control the switching of the first rocker arm 102. In the exemplary embodiment depicted, the first switching mechanism 302 includes a piston 304, a first pin 306, and a second pin 308 that are mechanically coupled in series, so that an actuation motion applied to the piston 304 pushes the first pin 306 and the second pin 308 to move accordingly, for example, as Figure 3, and moves horizontally to the right as shown. The piston 304 of the first switching mechanism 302 can be accommodated in a chamber 310 formed in a main body portion 312 of the main exhaust rocker arm 102. For example, the chamber 310 can be a fluid chamber connected to a controllable fluid supply source, such as an oil control valve suitable for providing pressurized oil to the chamber 310 as needed. In this case, the piston 304 can be configured with a surface area (such as, the recessed area, flat area, or other possible area with a surface structure shown), which is suitable for receiving a pressurized fluid (e.g., oil) to increase the hydraulic pressure in the chamber 310, thereby being able to actuate the piston 304 (e.g., horizontally to the right as shown). Alternatively or additionally, the piston 304 can be actuated by a force source other than a pressurized fluid, such as mechanically, electrically, or in a manner familiar to those skilled in the art.

[0033] exist Figure 3 In the embodiment shown in , the first pin 306 (one end of which is movably coupled to or in contact with the piston 304) is shown as being at least partially accommodated by the deactivation roller 112, so that when the piston 304 is actuated, the movement of the piston 304 can correspondingly push the first pin 306 to translate along a certain distance through the internal volume portion formed in the deactivation roller 112. The other end of the first pin 306 can then be movably coupled to or engaged with the second pin 308. Most of the second pin 308 is shown as being received by a passage formed inside the main body portion 312 of the first rocker arm 102, so that when actuated by the piston 304, the second pin 308 can slide through the passage and extend out of the passage. Although depicted as having a generally cylindrical shape, the first pin 304 and the second pin 306 can be constructed to be different from the shapes shown. It should also be understood that although the term "pin" is used for description, these features are not limited to this. Those skilled in the art will recognize that a latch, block, capsule or other suitable structure may also be used, which may be provided with a profile that matches the interior space of the deactivated roller or the receiving passage of the first rocker arm body so as to be arranged therein in a manner that can be translated.

[0034] In a specific embodiment, in order to achieve switching (e.g., valve deactivation), the first pin 306 between the piston 304 and the second pin 308 can be allowed to move relative to the piston 304 and the second pin 308 in a direction substantially perpendicular to the direction of travel of the first switching mechanism 302. For example, the length of the first pin 306 can be substantially equal to the lateral length of the deactivation roller 112. In this way, when driven, the first pin 306 can slide to a position where its entire body is received within the outer boundary of the deactivation roller 112, thereby allowing the first pin 306 to travel together with the deactivation roller 112 (e.g., in Figure 3The configuration of the first rocker arm 102 is as follows: Figure 4 This type of operation may be referred to as deactivation, wherein the movement of the first cam 106 is absorbed by the vertical displacement between the deactivation roller 112 and the first rocker arm 102. Conversely, for example, when it is desired to activate the valve, the first pin 306 may be retracted to Figure 3 , wherein the end of the first pin 306 associated with the piston 304 extends beyond the deactivation roller 112 and further engages with the side wall of the first rocker arm 102 to lock the deactivation roller 112 firmly fixed to the first rocker arm 102. When this occurs, the first rocker arm 102 switches to the enabled mode and is therefore able to actuate the associated engine valve.

[0035] In a specific embodiment, the length of the second pin 308 can be greater than the length of the receiving passage of the first rocker arm 102 to the extent that either end of the second pin 308 can extend beyond the lateral perimeter of the passage. Figure 3 In the locked position shown in FIG. 1 , the end of the second pin 308 that contacts the first pin 306 can extend into the deactivation roller 112, thereby further locking the deactivation roller 112 with the first rocker arm 102. Figure 4 In the unlocked position shown in FIG. 1 , the end of the second pin 308 that contacts the first pin 306 is driven away from the deactivation roller 112 (i.e., not engaged with the deactivation roller), thereby unlocking the deactivation roller 112 to enable it to move relative to the first rocker arm 102. The other end of the second pin 308 then extends outward from the passage and thus drives the second switching mechanism of the second rocker arm 104, which will be described in more detail below.

[0036] In a specific embodiment, the second switching mechanism of the second rocker arm 104 can take the form of a sliding valve 314, which is configured to be coupled to the second pin 308 and arranged to be in physical contact with the second pin, so that the horizontal movement of the second pin 308 can drive the sliding valve 314 accordingly. Alternatively, other suitable structures of the second switching mechanism can be envisioned, such as hydraulic capsules, etc. In a specific embodiment, the sliding valve 314 can be arranged in the roller shaft 316 of the second rocker arm 104 and configured to be able to move between a first position and a second position. In the illustrated embodiment, the outer wall of the sliding valve 314 can be configured with an annular groove, a recess, a through passage or other suitable structures, which can advantageously form a flow channel 318 that allows fluid to pass through. In some examples, the first flow circuit and the second flow circuit (not visible in the drawings) can be ported to two corresponding openings formed on the inner wall of the roller shaft 316. As configured, when the spool valve 314 is driven by the first switching mechanism 302 to (e.g., pushed by the second pin 308) an appropriate position where the flow channel 318 on the spool valve 314 is aligned with and / or engaged with the two openings, the pressurized fluid can flow from one opening to the other opening through the flow channel 318, thereby achieving fluid communication between the first flow circuit and the second flow circuit. As an example and not limitation, the first flow circuit can be a fluid supply circuit that can be connected to an oil supply source, for example, while the second flow circuit can be fluidly connected to the engine brake capsule 110, which can be controlled via the pressurized fluid flow to translate between an extended position and a retracted position, thereby enabling and disabling actuation of the brake valve accordingly.

[0037] In addition, in a specific embodiment, a return spring 324 can be provided, which is used to bias both the first switching mechanism and the second switching mechanism. For example, the return spring 324 can be connected to the end of the sliding valve 314 opposite to the end that contacts the second pin 308. In the illustrated embodiment, the return spring 324 can be at least partially accommodated by the end of the sliding valve 314 so that the return spring 324 applies a biasing force to the end of the sliding valve 314. As another example, the return spring 324 can advantageously have a certain preload so as to push both the sliding valve 314 and the first switching mechanism 302 back to the neutral position (i.e., as shown in Figure 1) when the piston 304 is not actuated. Figure 3 ). When this happens, the flow passage 318 arranged on the slide valve 314 can be offset relative to the openings connected to the first fluid circuit and the second fluid circuit, respectively, thereby interrupting the fluid communication and cutting off the fluid supply to the engine brake capsule 110. At the same time, the return spring 324 also pushes the first switching mechanism 302 (e.g., via the second switching mechanism) to the locked position (e.g., Figure 3), and thus the first rocker arm 102 is switched to the enabled state. Alternatively, as will be appreciated by those skilled in the art, other suitable biasing elements may be provided in place of the return spring 324 to perform the desired functions of the present disclosure.

[0038] The following will refer to Figure 3 to Figure 4 The operation of the synchronization system according to the present disclosure is further described, wherein: Figure 3 shows the system in drive mode, while Figure 4 The system is shown in a braking mode. In operation, a single actuation source can be employed that is used to drive both the first switching mechanism and the second switching mechanism in a synchronized manner. For example, an oil control valve (not shown) can be ported to a chamber 310 within the first rocker arm 102 and feed pressurized oil to the chamber 310. The increase in oil pressure can force the piston 304 to move horizontally to the right (as shown), thereby pushing the first pin 306 and the second pin 308 to an unlocked position that allows the deactivation roller 110 to be released from engagement with the first rocker arm 102, thereby switching the first rocker arm 102 to a deactivated state ( Figure 4 ). This movement of the first switching mechanism 302 in turn drives the slide valve 314 to shift to a certain extent until the flow channel 318 formed on the slide valve 314 leads to the first fluid circuit and the second fluid circuit arranged inside the second rocker arm 104. Therefore, a flow path is formed that enables the fluid supplied from the first fluid circuit to flow through the slide valve 314 and the second fluid circuit until it finally reaches the engine brake capsule 110 connected downstream. In this way, the main lift deactivation and engine brake activation can be synchronously controlled by a single oil control valve. In addition, in some embodiments, the flow channel 318 located on the slide valve 314 can be used to generate a delay between the valve deactivation process and the start of the engine capsule extension, so that the main event deactivation and engine brake activation can be controlled to be staggered without overlapping.

[0039] Conversely, when the drive mode is required, the oil control valve can stop injecting pressurized oil into the chamber 310. Without this hydraulic actuation force, the first switching mechanism and the second switching mechanism can be biased to the left by the return spring 324 and returned to the Figure 3 . In this configuration, the first switching mechanism 302 securely locks the deactivation roller 112 to the first rocker arm 102, thereby enabling the first rocker arm 102 to perform a primary lift event. At the same time, the spool valve 314 is also biased by the return spring 324 to a position where the flow passage 318 is disconnected from the first fluid circuit and the second fluid circuit, so that the fluid supply to the engine brake capsule 110 is interrupted. Therefore, the second rocker arm 104 is switched to the deactivated state.

[0040] Reference now Figure 5, shows the relative positions of the first switching mechanism 302 and the spool valve 314 when the first rocker arm 102 is in the full lift drive mode and the second rocker arm 104 is deactivated. In this case, the first switching mechanism 302 is in its locked position, thereby locking the deactivation roller 112 in a fixed relationship with the first rocker arm 102 to enable a primary lift event. At the same time, the engine brake capsule 110 is deactivated because its pressurized fluid supply is cut off by the spool valve 314 in the neutral position. Figure 5 As shown in FIG. 1 , when the first rocker arm 102 is activated to reach the full lift position, although the second pin 306 of the first switching mechanism 302 and the spool valve 314 in the second rocker arm 104 are relatively vertically displaced, they still maintain a certain level of contact (although minimal contact). Therefore, it can be advantageously ensured that the spring force from the return spring 324 can continue to be applied to the first switching mechanism 302, thereby biasing the first switching mechanism 302 to keep it firmly locked during the activation of the entire main lift event.

[0041] Figure 6 Another possible embodiment of a synchronization system according to the present disclosure is shown. In this exemplary embodiment, two rocker arms 602 and 604 are provided, which can be arranged to be pressed against each other in a substantially liquid-tight manner, for example, under the force applied by two biasing springs 606 and 608 (as shown) connected to the rocker arms 602 and 604, respectively. Alternatively, the two rocker arms 602 and 604 can be tightly positioned with each other in other ways by other suitable retaining means (such as mechanical fasteners, etc.). In the exemplary embodiment shown, the first rocker arm 602 can be pivotally supported by a rocker shaft 610 at one end (for example, rotating around the axis in a manner known in the art), and a first switching mechanism 612 is provided near the other end. Similarly, the second rocker arm 604 can also be pivotally supported by a rocker shaft 610 at one end, and a second switching mechanism 636 is provided near the other end. The first switching mechanism 612 and the second switching mechanism 636 can advantageously enable the first rocker arm 602 and the second rocker arm 604 to be synchronously switched in a desired switching sequence under the control of a single actuation source.

[0042] In order to control the displacement of the first switching mechanism 612 as required, in a specific embodiment, the first switching mechanism 612 can be configured with a piston 614, which is similar to the above reference Figures 3 to 5The piston 614 functions in a similar manner to the piston 304 described above. For example, the piston 614 can be actuated by a force source such as a force source formed by an injected pressurized fluid flowing to the piston 614 through a path formed in the first rocker arm 602. Of course, other actuation means can also be used to mechanically, electrically, or otherwise drive the piston 614 as desired. In a specific embodiment, the first locking pin 616 is connected to the piston 614 at the other end of the piston 614 opposite to the end associated with the actuation source, so that when the piston 614 is actuated, the movement of the piston 614 can be correspondingly (for example, as shown in FIG. 1 ). Figure 6 , in the vertical direction) pushes the first locking pin 616 downward. In the illustrated embodiment, the locking pin 616 is shown as being received in an internal space defined by a first deactivation roller 618, which is configured to be relatively displaced relative to the first rocker arm body in a manner similar to the deactivation roller 112 described above to achieve switching. Again, although the term "pin" is used for description, it should be understood that this feature can take the form of other suitable structures to achieve the desired functions of the present disclosure.

[0043] In a particular embodiment, the locking pin 616 is also connected to a spool valve 620 that is located in a chamber 630 formed inside the first rocker arm 602. For example, the spool valve 620 can be arranged in a straight line with the piston 614, so that when the first deactivation roller 618 travels to a proper position relative to the first rocker arm 602, the first locking pin 616 accommodated by the inner space of the first deactivation roller 618 can be sandwiched between the piston 614 and the spool valve 620 and coaxially aligned with the piston and the spool valve.

[0044] In addition, Figure 6 In the embodiment shown in , the outer surface of the sliding valve 620 can be provided with surface structures, such as annular channels, recesses, etc., which can advantageously allow fluid to pass through. In a specific embodiment, a first fluid circuit 622 and a second fluid circuit 624 can be formed inside the first rocker arm 602. As an example and not limitation, the first fluid circuit 622 can be connected to a fluid source for providing pressurized oil to the chamber 630, such as an engine pump, and the second fluid circuit 624 can be routed from the chamber 630 to an interface 626 formed between the first rocker arm 602 and the second rocker arm 604. Both the first fluid circuit 622 and the second fluid circuit 624 can open into the chamber 630 at a certain position, which makes it possible for the sliding valve 620 to be opened when the sliding valve 620 is open (for example, Figure 6), the first fluid circuit 622 and the second fluid circuit 624 may be in communication with the annular passage formed around the spool valve 620, thereby allowing the pressurized fluid supplied from the first fluid circuit 622 to flow around the spool valve 620 and reach the second fluid circuit 624. Conversely, in a case where the grooves of the spool valve 620 are not aligned with the first fluid circuit 622 and the second fluid circuit 624 (e.g., when the first switching mechanism 612 is in the locked position), the spool valve 620 may interrupt the fluid communication between the first fluid circuit 622 and the second fluid circuit 624.

[0045] like Figure 6 As further shown in FIG. 6 , the slide valve 620 can be provided with a first return spring 628 attached to the other end of the slide valve opposite the end that contacts the locking pin 616. For example, the return spring 628 can be accommodated in a cavity formed at the end of the slide valve 620. In a specific embodiment, the return spring 628 can apply a spring force (e.g., in an upward direction) to push the slide valve 620 back to a default position (e.g., Figure 7 , which will be described in more detail below), and thereby also drives the first locking pin 616 and the piston 614 vertically upward.

[0046] In a specific embodiment, the second rocker arm 604 located downstream of the first rocker arm 602 can be configured with a third fluid circuit 632, which can, for example, be led to the interface 626 between the first rocker arm 602 and the second rocker arm 604 so as to form a fluid connection with the opening of the second fluid circuit 624 on the interface 626. The other end of the third fluid circuit 632 can be led to a fluid chamber 634 that accommodates a portion of the second switching mechanism 636. In this way, the fluid supplied from the first rocker arm 602 can flow to the second rocker arm 604 through the interface 626. When this happens, the fluid (such as pressurized oil) injected into the fluid chamber 634 can cause the second switching mechanism 636 to move downward in the vertical direction, for example as shown.

[0047] In a specific embodiment, the second switching mechanism 636 may be provided with a valve structure 638 configured to be hydraulically actuated by the fluid flowing into the fluid chamber 634. As an example, the valve structure 638 may be designed with a through passage that fluidically connects the end of the third fluid circuit 632 with the inner space of the fluid chamber 634. Alternatively or additionally, the outer wall of the valve structure 638 may also be provided with a groove to form an additional fluid passage around the valve structure 638.

[0048] like Figure 6As further shown in , the end of the valve structure 638 opposite to the end associated with the fluid can be further connected to the second locking pin 640 in a motion-transmitting manner, so that the movement of the valve structure 638 (for example, downward when driven by increasing the fluid pressure in the fluid chamber 634) can drive the second locking pin 640 accordingly. The second locking pin 640 can have a generally cylindrical shape and can be assembled through the internal space of the second deactivation roller 642 of the second rocker arm 604 so as to be movably accommodated in the internal space. It is noted again that the second locking pin 640 can be configured in a manner different from that shown to perform the desired operation of the present disclosure. The lower end of the second locking pin 640 can be connected to a biasing element (including a second return spring 644) that is used to apply an upward spring force to the second switching mechanism 636. Configured in this manner, it should be understood that the second switching mechanism 636 can perform a switching function similar to the switching function described above, for example, to the extent that the second switching mechanism 636 moves downward until the valve structure 638 and the second locking pin 640 are locked with the second deactivation roller 642 and the lift event of the second rocker arm 604 is effectively enabled.

[0049] refer to Figure 7 and Figure 8 , describes Figure 6 The operation of a synchronous system in which Figure 7 The first switch mechanism 612 is shown in a first position (eg, locked state), and Figure 8 The first switching mechanism 612 is shown in a second position (eg, unlocked state).

[0050] exist Figure 7 In the locked position, for example, when the actuation force is no longer applied to the piston 614, the biasing force from the first return spring 628 can be transmitted in the opposite direction to the actuation force received by the piston 614 (for example, as Figure 7 614. The first rocker arm 602 is shown in the figure, and the first rocker arm 602 is shown in the figure ...

[0051] When biased to the default position, the grooves formed on the outer surface of the spool valve 620 can be offset relative to the corresponding openings of the first fluid circuit 622 and the second fluid circuit 624, so that any fluid flow originating from the first fluid circuit 622 is blocked by the hard outer wall of the spool valve 620. Figure 7604 is disabled, specifically, the fluid communication to the fluid chamber 634 associated with the second switching mechanism 636 is disabled. Therefore, due to the absence of hydraulic actuation force in the fluid chamber 634, the second switching mechanism 636 can return to the unlocked position under the action of the second return spring 644, thereby switching the second rocker arm 604 to the deactivated state. In this way, the deactivation of the second rocker arm 604 can be achieved after the activation of the first rocker arm 602, thereby ensuring that the switching sequence of the first rocker arm 602 and the second rocker arm 604 is correct.

[0052] Now go to Figure 8 , shows a second position of the first rocker arm 602, wherein the first switching mechanism 612 is driven by a force source (e.g., under the control of an oil control valve) to horizontally shift leftward to the extent that the first deactivation roller 618 is released. In this case, the slide valve 620 is pushed to an appropriate position, at which the groove on the slide valve 620 can intersect both the first fluid circuit 622 and the second fluid circuit 624, thereby achieving fluid communication therebetween. Therefore, the fluid supplied from the first fluid circuit 622 can flow through the second fluid circuit 624, pass through the interface 626 between the first rocker arm 602 and the second rocker arm 604, flow into the third fluid circuit 632, and finally flow to the fluid chamber 634 ( Figure 8 604). An increase in fluid pressure in the fluid chamber 634 may shift the second switching mechanism 636 to the locked position, thereby activating the second rocker arm 604. In this way, a single motion source (e.g., an oil control valve coupled to the first rocker arm 602) may be used to simultaneously control the deactivation of the first rocker arm 602 and the activation of the second rocker arm 604.

[0053] The various possible embodiments described above may be used in combination or sub-combination to achieve some (if not all) of the advantages of the present disclosure. Features described with reference to one embodiment may also be applied to other embodiments, as long as necessary modifications are made in a manner familiar to those skilled in the art. For example, reference may be used instead. Figures 1 to 5 The configuration described has a second rocker arm with an engine brake capsule to replace Figures 6 to 8 As another example, Figures 1 to 5 The first rocker arm provided with a second pin mechanically coupled to the second rocker arm can be modified to include one or more fluid circuits to hydraulically engage with the second rocker arm. It should be understood that other possible combinations or design changes can be conceived by ordinary technicians in this field based on the specification, claims and drawings without departing from the scope of the present disclosure.

[0054] As used herein, "or" is inclusive and non-exclusive, unless expressly stated otherwise or the context indicates otherwise. Thus, as used herein, "A or B" means "A, B, or both," unless expressly stated otherwise or the context indicates otherwise. Furthermore, "and" includes both conjunctive and disjunctive, unless expressly stated otherwise or the context indicates otherwise. Thus, as used herein, "A and B" means "A and B conjunctive or A and B disjunctive," unless expressly stated otherwise or the context indicates otherwise.

[0055] The scope of the present disclosure covers all changes, substitutions, variations, alterations and modifications to the exemplary embodiments described or shown herein that will be understood by those of ordinary skill in the art. The scope of the present disclosure is not limited to the exemplary embodiments described or shown herein. In addition, although the present disclosure describes and shows the various embodiments herein as including specific parts, elements, features, functions, operations or steps, any of these embodiments may include any combination or arrangement of any parts, elements, features, functions, operations or steps described or shown anywhere in this article that will be understood by those of ordinary skill in the art. In addition, the devices or systems or parts of the devices or systems mentioned in the attached claims that are suitable for, arranged to, capable of, configured to, enabled to, operable to or operated to perform specific functions cover such devices, systems, and parts, that is, whether the device, system, or part is enabled, turned on or unlocked, as long as the device, system or part is so suitable for, arranged to, capable of, configured to, enabled to, operable to or operated to perform the specific function. In addition, although the present disclosure describes or shows specific embodiments that provide specific advantages, specific embodiments may not provide advantages, provide partial advantages, or provide all advantages.

Claims

1. A system for synchronization, comprising: a first rocker arm configured to switch between a first mode and a second mode; a second rocker arm configured to switch between a third mode and a fourth mode; a first switching mechanism disposed in the first rocker arm and configured to controllably switch the first rocker arm between the first mode and the second mode by moving between a first position and a second position; as well as a second switching mechanism disposed in the second rocker arm and configured to controllably switch the second rocker arm between the third mode and the fourth mode by moving between a third position and a fourth position; wherein the movement of the first switching mechanism and the movement of the second switching mechanism are actuated by a single actuation source; and The movement of the first switching mechanism between the first position and the second position causes the second switching mechanism to move between the third position and the fourth position, thereby performing the switching of the first rocker arm and the switching of the second rocker arm in sequence.

2. The system according to claim 1, wherein: The single actuation source is a fluid control valve.

3. The system according to claim 1, wherein: The first rocker arm and the second rocker arm are arranged closely to each other.

4. The system according to claim 1, wherein: At least a portion of the first switching mechanism and at least a portion of the second switching mechanism are configured to maintain physical contact with each other. 5 . The system of claim 4 , further comprising a return spring coupled to the second switching mechanism and configured to bias both the first switching mechanism and the second switching mechanism.

6. The system according to claim 1, wherein: The first rocker arm includes a deactivation roller configured to be selectively locked by the first switching mechanism such that the first rocker arm selectively switches between the first mode and the second mode.

7. The system according to claim 1, wherein: The second rocker arm includes a first fluid circuit and a second fluid circuit.

8. The system according to claim 7, wherein: The second switching mechanism includes a slide valve.

9. The system according to claim 8, wherein: The spool valve is configured to selectively enable or disable fluid communication between the first fluid circuit and the second fluid circuit of the second rocker arm so that the second rocker arm is selectively switched between the third mode and the fourth mode.

10. The system according to claim 1, wherein: The first switching mechanism includes a slide valve.

11. The system according to claim 10, wherein: The first rocker arm includes a first fluid circuit and a second fluid circuit.

12. The system according to claim 11, wherein: The spool valve is configured to selectively enable or disable fluid communication between the first fluid circuit and the second fluid circuit of the first rocker arm.

13. The system according to claim 12, wherein: The second rocker arm includes a third fluid circuit configured to hydraulically engage the second fluid circuit of the first rocker arm.

14. The system according to claim 13, wherein: Movement of the second switching mechanism is actuated by fluid supplied from the first fluid circuit through the second fluid circuit to the third fluid circuit, so that the second rocker arm switches between the third mode and the fourth mode.

15. The system of claim 14, further comprising: a first return spring coupled to the first switching mechanism and configured to bias the first switching mechanism; and a second return spring coupled to the second switching mechanism and configured to bias the second switching mechanism.

16. The system of claim 1, wherein: The first rocker arm and the second rocker arm are biased against each other by one or more biasing springs.

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