Intake valve late-closing device, intake valve assembly, and engine

Abstract

An intake valve late-closing device, comprising a cam shaft (100), a rocker arm shaft (200), an intake rocker arm (300), a main roller (400), a control unit (500), a movable unit, a contact portion, and a return spring (800). In the present intake valve late-closing device, an intake valve late-closing rocker arm in the prior art is eliminated; instead, the movable unit is movably connected to the intake rocker arm, and when a solenoid valve is closed, an intake cam is in contact with the main roller, and an intake valve late-closing roller remains in contact with an intake late-closing cam, but only compresses the return spring.

Description

An intake valve late closing device, an intake valve assembly, and an engine Technical Field

[0001] This invention belongs to the field of engine technology and relates to an intake valve late closing device, an intake valve assembly, and an engine. Background Technology

[0002] With increasingly stringent emission regulations, nitrogen oxide emissions have become a pressing issue. Late intake valve closing technology is an effective means of thermal management for engine aftertreatment. It reduces intake airflow, increasing exhaust temperature with the same fuel quantity, thereby improving the SCR conversion efficiency of nitrogen oxides. Late intake valve closing technology also allows for an expansion ratio greater than the compression ratio, improving engine efficiency. In addition to the main lift, the late intake valve closing device can provide a late valve closing lift to achieve the function. Several invention patents currently involve the application of this technology.

[0003] For example, a patent application with application number CN202280048963.1, filed by Eaton Intelligent Power Co., Ltd., discloses a rocker arm assembly with a main rocker arm and a forked auxiliary rocker arm. This invention discloses a rocker arm assembly that may include a main rocker arm, an auxiliary rocker arm, and a freewheeling spring mounted on the main rocker arm and the auxiliary rocker arm. The main rocker arm may include a main body surrounding the main rocker arm orifice, a valve end, a main cam end, and a main latching orifice between the valve end and the main cam end. The auxiliary rocker arm may include a forked auxiliary body. A first auxiliary rocker arm orifice and a second auxiliary rocker arm orifice may be located on the side flanks of the main rocker arm orifice. A first auxiliary cam end and a second auxiliary cam end may be located on the side flanks of the main cam end. A first auxiliary latching orifice and a second auxiliary latching orifice may be located on the side flanks of the main latching orifice. The freewheeling spring may span the main latching orifice.

[0004] For example, a patent application with application number CN201280025665.7, filed by Jacobs Vehicle Systems, discloses a main and auxiliary rocker arm assembly for actuating engine valves. This invention discloses a system and method for actuating engine valves. The system may include a main rocker arm and an auxiliary rocker arm disposed adjacent to each other on a rocker arm shaft. The main rocker arm can actuate the engine valve in response to a first valve assembly element, such as a cam, for actuating movement of the main valve, for example, a main exhaust event. The auxiliary rocker arm can receive one or more auxiliary valve actuating movements (e.g., engine braking, exhaust gas recirculation, and / or brake gas recirculation events) from a second valve assembly element to actuate one of the engine valves. A main piston and a slave piston are disposed in the main rocker arm. The main piston can be actuated by the auxiliary rocker arm.

[0005] In summary, some existing technical solutions have complex structures. When the engine is working normally, the intake valve late closing cam still drives the intake valve late closing rocker arm to swing around the rocker arm axis, increasing friction work and thus increasing the overall fuel consumption of the engine. There is considerable room for improvement. Technical issues

[0006] In view of the above-mentioned shortcomings of the prior art, the technical problem to be solved by the present invention is to provide an intake valve late closing device, an intake valve assembly, and an engine. Technical solutions

[0007] The purpose of this invention is to address the aforementioned problems in the prior art by providing an intake valve late closing device, an intake valve assembly, and an engine.

[0008] The objective of this invention can be achieved through the following technical solution: an intake valve late-closing device, comprising:

[0009] Camshaft, which includes intake camshaft and intake closing camshaft;

[0010] The rocker arm shaft has its axis direction parallel to that of the camshaft.

[0011] An intake rocker arm is fitted with the rocker arm shaft through a shaft hole. The intake rocker arm can swing back and forth around the rocker arm shaft. The intake rocker arm is provided with a control hole and a movable hole. One end of the movable hole is connected to the control hole, and the other end of the movable hole is connected to the outside.

[0012] The main roller is rotatably connected to the intake rocker arm and can contact the intake cam.

[0013] A control unit, located at the control port, is used to supply or discharge engine oil.

[0014] The movable unit includes a movable block and an intake valve late-closing roller. The movable block is located at the end of the movable hole near the outside and can move along the axis of the movable hole. The intake valve late-closing roller is rotatably connected to the movable block and can contact the intake valve late-closing cam.

[0015] A contact portion, which is connected to the intake rocker arm and located at the end of the movable hole near the control hole;

[0016] A return spring, one end of which contacts the movable block, and the other end of which contacts the contact portion, pushes the movable block away from the intake rocker arm along the axial direction of the movable hole;

[0017] When the solenoid valve is closed, the intake cam contacts the main roller and drives the intake rocker arm to swing around the rocker arm axis through the main roller. The intake valve closing cam contacts the intake valve closing roller and drives the movable block to move along the axial direction of the movable hole and compress the return spring.

[0018] When the solenoid valve is opened, the engine oil enters the movable hole through the control unit and drives the movable block to move away from the intake rocker arm along the axis of the movable hole. This causes the intake cam to separate from the main roller and form a pause gap. The intake valve closing cam contacts the intake valve closing roller and drives the movable block through the intake valve closing roller to drive the intake rocker arm to swing around the rocker arm axis.

[0019] In the aforementioned intake valve late-closing device, the contact part is configured as a spring seat, the spring seat is perpendicular to the moving direction of the movable block, at least a portion of the spring seat is connected to the intake rocker arm, and one end of the return spring contacts the spring seat.

[0020] In the aforementioned intake valve late-closing device, the spring seat is provided with a first contact surface, which is perpendicular to the moving direction of the movable block. The return spring has a spiral structure and is provided with a second contact surface, which is perpendicular to the moving direction of the movable block. The second contact surface contacts the first contact surface.

[0021] In the aforementioned intake valve late-closing device, the movable block is provided with a third contact surface, which is perpendicular to the moving direction of the movable block. The return spring has a helical structure and is provided with a fourth contact surface, which is perpendicular to the moving direction of the movable block and contacts the third contact surface.

[0022] In the aforementioned intake valve late-closing device, the spring seat is provided with a positioning protrusion, the positioning protrusion is located on the side of the spring seat near the return spring, and the end of the return spring near the spring seat is sleeved on the positioning protrusion and has an interference fit with the positioning protrusion.

[0023] In the aforementioned intake valve late-closing device, the movable block is provided with a positioning recess, the positioning recess is located on the side of the movable block near the return spring, and the end of the return spring near the movable block is embedded in the positioning recess.

[0024] In the aforementioned intake valve late-closing device, the positioning recess is provided with a fixed protrusion. The fixed protrusion is located on the inner periphery of the positioning recess near the bottom end. The inner diameter of the fixed protrusion is smaller than the inner diameter of the positioning recess. The return spring near the movable block end is interference-fitted with the fixed protrusion.

[0025] In the aforementioned intake valve late-closing device, the spring seat is provided with an oil passage hole, which is distributed along the axial direction of the spring seat and passes through the middle of the spring seat.

[0026] In the aforementioned intake valve late-closing device, a limiting unit is further included. The limiting unit is disposed on one of the intake rocker arm and the movable block, and can contact the other of the intake rocker arm and the movable block, thereby limiting the separation of the movable block from the intake rocker arm.

[0027] In the aforementioned intake valve late-closing device, the limiting unit includes a limiting pin, which is disposed on the movable block and can contact the intake rocker arm.

[0028] In the aforementioned intake valve late-closing device, the movable block is provided with an internal thread portion, and the limiting pin is provided with an external thread portion. The limiting pin and the movable block are threadedly connected through the external thread portion and the internal thread portion.

[0029] In the aforementioned intake valve late-closing device, the intake rocker arm is further provided with a limiting groove, and the limiting pin can contact the intake rocker arm through the limiting groove.

[0030] An intake valve late-closing device is also provided, comprising:

[0031] Camshaft, which includes intake camshaft and intake closing camshaft;

[0032] The rocker arm shaft has its axis direction parallel to that of the camshaft.

[0033] An intake rocker arm is fitted with the rocker arm shaft through a shaft hole. The intake rocker arm can swing back and forth around the rocker arm shaft. The intake rocker arm is provided with a control hole and a movable hole. One end of the movable hole is connected to the control hole, and the other end of the movable hole is connected to the outside.

[0034] The main roller is rotatably connected to the intake rocker arm and can contact the intake cam.

[0035] A control unit, located at the control port, is used to supply or discharge engine oil.

[0036] The movable unit includes a movable block and an intake valve late-closing roller. The movable block is located at the end of the movable hole near the outside and can move along the axis of the movable hole. The intake valve late-closing roller is rotatably connected to the movable block and can contact the intake valve late-closing cam.

[0037] A clearance spring, one end of which is connected to the intake rocker arm, and the other end of which is in contact with the movable block, pushes the movable block closer to the intake rocker arm along the axial direction of the movable hole, thereby forming a clearance gap between the intake valve closing roller and the intake rocker arm.

[0038] When the solenoid valve is closed, the intake cam contacts the main roller and drives the intake rocker arm to swing around the rocker arm axis through the main roller;

[0039] When the solenoid valve is opened, the engine oil enters the movable hole through the control unit and drives the movable block to move away from the intake rocker arm along the axis of the movable hole, thereby eliminating the clearance and separating the intake cam from the main roller to form a pause gap. The intake valve closing cam contacts the intake valve closing roller and drives the movable block through the intake valve closing roller to drive the intake rocker arm to swing around the rocker arm axis.

[0040] An intake valve assembly is also provided, including the aforementioned intake valve late-closing device, further comprising: an intake valve bridge and an intake valve, wherein a valve clearance is formed between the intake valve bridge and the intake rocker arm, the intake rocker arm can contact the intake valve bridge, and the intake valve is connected to the intake valve bridge;

[0041] When the solenoid valve is closed, the intake cam contacts the main roller and drives the intake rocker arm to swing around the rocker arm axis through the main roller, thereby eliminating the valve clearance and driving the intake valve bridge to open the intake valve;

[0042] When the solenoid valve is opened, the intake valve closing cam contacts the intake valve closing roller and drives the movable block through the intake valve closing roller to swing the intake rocker arm around the rocker arm shaft, thereby eliminating the valve clearance and driving the intake valve bridge to open the intake valve.

[0043] In one of the above-mentioned intake valve assemblies, the intake rocker arm is further provided with an adjusting bolt, the valve clearance is formed between the adjusting bolt and the intake valve bridge, the adjusting bolt is used to adjust the size of the valve clearance, and the intake rocker arm can contact the intake valve bridge through the adjusting bolt.

[0044] An engine is also provided, including the aforementioned intake valve assembly. Beneficial effects

[0045] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0046] 1. The intake valve late-closing rocker arm in the existing technology is eliminated. Instead, it is movably connected to the intake rocker arm through a movable unit. When the solenoid valve is closed, the intake cam is in contact with the main roller, and the intake valve late-closing roller is in contact with the intake late-closing cam but only the return spring is compressed. When the solenoid valve is open, the oil pressure pushes the movable block to a position away from the intake rocker arm. The intake late-closing cam is still in contact with the intake valve late-closing roller but the return spring is no longer compressed. The intake cam is separated from the main roller and a pause gap is formed, so it no longer functions.

[0047] 2. Regardless of whether the solenoid valve is open or closed, the return spring pushes the intake valve closing cam to always be in contact with the intake valve closing roller. Compared with the structure without a return spring, this eliminates the time that the oil needs to push the moving block away from the intake rocker arm and contact the intake valve closing cam the moment the solenoid valve is opened. In addition, the return spring and the oil exert force in the same direction, which can further shorten the time for the intake valve closing device to take effect.

[0048] 3. Flatten the end of the spiral return spring to form a second contact surface with a planar structure, increasing the contact area between the spring seat and the return spring, so that the direction of the force applied by the corrective spring to the spring seat is exactly the direction of movement of the movable block; flatten the end of the spiral return spring to form a fourth contact surface with a planar structure, increasing the contact area between the movable block and the return spring, so that the direction of the force applied by the corrective spring to the movable block is exactly the direction of movement of the movable block.

[0049] 4. The limiting pin can contact the intake rocker arm, thereby restricting the separation of the movable block from the intake rocker arm. It can also prevent the movable block from falling out of the intake rocker arm when the intake valve flies off due to abnormal engine operation. The limiting groove can limit the limiting pin, preventing relative slippage of the limiting pin due to the slope of the contact position when it contacts the intake rocker arm, so that the limiting pin always falls in the limiting groove to achieve contact with the intake rocker arm.

[0050] 5. The intake valve late-closing rocker arm in the existing technology is eliminated. Instead, it is movably connected to the intake rocker arm through a movable unit. When the solenoid valve is closed, the intake cam contacts the main roller, and the avoidance spring pushes the intake valve late-closing roller to separate from the intake valve late-closing cam. When the solenoid valve is open, the oil pressure pushes the movable block to move away from the intake rocker arm, so that the intake valve late-closing cam contacts the intake valve late-closing roller and separates the intake cam from the main roller, forming a pause gap so that it no longer functions. Attached Figure Description

[0051] Figure 1 is a schematic diagram of the structure of an intake valve late-closing device according to an embodiment of the present invention.

[0052] Figure 2 is a schematic diagram of the structure of the intake rocker arm, main roller and moving unit in a preferred embodiment of the present invention.

[0053] Figure 3 is a schematic diagram of the internal structure of the air intake rocker arm and the moving unit in a preferred embodiment of the present invention.

[0054] Figure 4 is a schematic diagram of the intake rocker arm in a preferred embodiment of the present invention.

[0055] Figure 5 is a schematic diagram of the spring seat in a preferred embodiment of the present invention.

[0056] Figure 6 is a schematic diagram of the structure of the active unit in a preferred embodiment of the present invention.

[0057] Figure 7 is a schematic diagram of the return spring in a preferred embodiment of the present invention.

[0058] Figure 8 is a schematic diagram of the intake valve late-closing device according to another embodiment of the present invention.

[0059] Figure 9 is a schematic diagram of the intake valve assembly according to an embodiment of the present invention.

[0060] Figure 10 is a schematic diagram of the intake valve assembly according to another embodiment of the present invention.

[0061] In the diagram, 100 is the camshaft; 110 is the intake camshaft; 120 is the intake valve closing camshaft; 200 is the rocker arm shaft; 300 is the intake rocker arm; 310 is the control hole; 320 is the movable hole; 330 is the limit groove; 340 is the adjusting bolt; 400 is the main roller; 500 is the control unit; 610 is the movable block; 611 is the third contact surface; 612 is the positioning recess; 613 is the fixing protrusion; 620 is the intake valve closing roller; 700 is the spring seat; 710 is the first contact surface; 720 is the positioning protrusion; 730 is the oil passage hole; 800 is the return spring; 810 is the second contact surface; 820 is the fourth contact surface; 900 is the limit pin; 1000 is the avoidance spring; 1100 is the intake valve bridge; and 1200 is the intake valve. Embodiments of the present invention

[0062] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0063] Example 1

[0064] As shown in Figures 1 to 7, an intake valve late-closing device includes: a camshaft 100, a rocker arm shaft 200, an intake rocker arm 300, a main roller 400, a control unit 500, a moving unit, a contact part, and a return spring 800.

[0065] The camshaft 100 includes an intake cam 110 and an intake closing cam 120.

[0066] Specifically, the intake cam 110 and the intake closing cam 120 are arranged adjacent to each other.

[0067] The axial direction of the rocker arm shaft 200 is parallel to the axial direction of the cam shaft 100.

[0068] The intake rocker arm 300 is engaged with the rocker arm shaft 200 through a shaft hole. The intake rocker arm 300 can swing back and forth around the rocker arm shaft 200. The intake rocker arm 300 is provided with a control hole 310 and a movable hole 320. One end of the movable hole 320 is connected to the control hole 310, and the other end of the movable hole 320 is connected to the outside.

[0069] The main roller 400 is rotatably connected to the intake rocker arm 300, and the main roller 400 can contact the intake cam 110.

[0070] The control unit 500 is located in the control hole 310, and the control unit 500 is used to supply or discharge engine oil.

[0071] Specifically, the control unit 500 is prior art well known to those skilled in the art, and its working principle is the same as that of the control mechanism in the patent publication number CN113431657A, entitled "An Energy-Saving and Consumption-Reducing Engine Braking Device".

[0072] The movable unit includes a movable block 610 and an intake valve 1200 closing roller 620. The movable block 610 is located at the end of the movable hole 320 near the outside and can move along the axis of the movable hole 320. The intake valve 1200 closing roller 620 is rotatably connected to the movable block 610 and can contact the intake valve 120 closing cam 120.

[0073] The contact portion is connected to the intake rocker arm 300 and is located at one end of the movable hole 320 near the control hole 310.

[0074] Specifically, the contact part can be a part of the intake rocker arm 300, integrally formed with the intake rocker arm 300; or it can be a separate part, which is fixedly connected to the intake rocker arm 300 by welding, riveting or other fixing methods.

[0075] One end of the return spring 800 contacts the movable block 610, and the other end of the return spring 800 contacts the contact portion. The return spring 800 pushes the movable block 610 away from the intake rocker arm 300 along the axial direction of the movable hole 320.

[0076] When the solenoid valve is closed, the intake cam 110 contacts the main roller 400 and drives the intake rocker arm 300 to swing around the rocker arm shaft 200 through the main roller 400. The intake closing cam 120 contacts the intake valve 1200 closing roller 620 and drives the movable block 610 to move along the axial direction of the movable hole 320 and compress the return spring 800.

[0077] When the solenoid valve is opened, engine oil enters the movable hole 320 through the control unit 500 and drives the movable block 610 to move away from the intake rocker arm 300 along the axis of the movable hole 320. This causes the intake cam 110 to separate from the main roller 400 and form a pause gap. At this time, under the drive of the intake closing cam 120, a high-pressure oil chamber is formed in the space between the movable block 610 and the control mechanism. The intake closing cam 120 contacts the intake valve 120 closing roller 620 and drives the movable block 610 to drive the intake rocker arm 300 to swing around the rocker arm shaft 200 through the intake valve 120 closing roller 620.

[0078] In this embodiment, the intake valve 1200 closing rocker arm in the prior art is eliminated. Instead, it is movably connected to the intake rocker arm 300 via a movable unit. When the solenoid valve is closed, the intake cam 110 contacts the main roller 400, and the intake valve 1200 closing roller 620 remains in contact with the intake valve 1200 closing cam 120, but only the return spring 800 is compressed. When the solenoid valve is open, the oil pressure pushes the movable block 610 to a position away from the intake rocker arm 300. The intake valve 120 and the intake valve 1200 closing roller 620 remain in contact, but the return spring 800 is no longer compressed, and the intake cam 110 is separated from the main roller 400, forming a pause gap and thus no longer functioning.

[0079] It is also worth noting that, regardless of whether the solenoid valve is open or closed, the return spring 800 pushes the intake valve closing cam 120 to always be in contact with the intake valve closing roller 620. Compared with the structure without the return spring 800, this eliminates the time required for the oil to push the movable block 610 away from the intake rocker arm 300 and into contact with the intake valve closing cam 120 the moment the solenoid valve opens. Furthermore, since the return spring 800 and the oil exert force in the same direction, the time for the intake valve closing device to take effect can be further shortened.

[0080] As shown in Figures 3 and 5, based on the above embodiment, the contact part is configured as a spring seat 700, the spring seat 700 is perpendicular to the moving direction of the movable block 610, at least a part of the spring seat 700 is connected to the air intake rocker arm 300, and one end of the return spring 800 is in contact with the spring seat 700.

[0081] Alternatively, the intake rocker arm 300 can be designed so that one side of the spring seat 700 is connected to the intake rocker arm 300.

[0082] As shown in Figures 3, 5, and 7, based on the above embodiment, the spring seat 700 is provided with a first contact surface 710, which is perpendicular to the moving direction of the movable block 610. The return spring 800 has a spiral structure and is provided with a second contact surface 810, which is perpendicular to the moving direction of the movable block 610. The second contact surface 810 contacts the first contact surface 710.

[0083] In this embodiment, the end of the spiral return spring 800 is flattened to form a second contact surface 810 with a planar structure, which increases the contact area between the spring seat 700 and the return spring 800, and the direction of the force applied by the correction spring to the spring seat 700 is exactly the direction of movement of the movable block 610.

[0084] As shown in Figures 3, 6, and 7, based on the above embodiment, the movable block 610 is provided with a third contact surface 611, which is perpendicular to the moving direction of the movable block 610. The return spring 800 has a spiral structure and is provided with a fourth contact surface 820, which is perpendicular to the moving direction of the movable block 610 and contacts the third contact surface 611.

[0085] In this embodiment, the end of the spiral return spring 800 is flattened to form a fourth contact surface 820 with a planar structure, which increases the contact area between the movable block 610 and the return spring 800, and the direction of the force applied by the correction spring to the movable block 610 is exactly the direction of movement of the movable block 610.

[0086] As shown in Figures 3, 5, and 7, based on the above embodiment, the spring seat 700 is provided with a positioning protrusion 720. The positioning protrusion 720 is located on the side of the spring seat 700 near the return spring 800. The end of the return spring 800 near the spring seat 700 is sleeved on the positioning protrusion 720 and has an interference fit with the positioning protrusion 720.

[0087] In this embodiment, the end of the return spring 800 near the spring seat 700 is sleeved on the positioning protrusion 720 and has an interference fit with the positioning protrusion 720, so that the end of the return spring 800 near the spring seat 700 is fixed relative to the spring seat 700 and will not move or rotate.

[0088] As shown in Figures 3, 6, and 7, based on the above embodiment, the movable block 610 is provided with a positioning recess 612. The positioning recess 612 is located on the side of the movable block 610 near the return spring 800, and the end of the return spring 800 near the movable block 610 is embedded in the positioning recess 612.

[0089] In this embodiment, the end of the return spring 800 near the movable block 610 is embedded in the positioning recess 612, thereby preventing the end of the return spring 800 near the movable block 610 from falling out of the movable block 610.

[0090] As shown in Figures 3, 6, and 7, based on the above embodiment, the positioning recess 612 is provided with a fixing protrusion 613. The fixing protrusion 613 is located on the inner periphery of the positioning recess 612 near the bottom. The inner diameter of the fixing protrusion 613 is smaller than the inner diameter of the positioning recess 612. The end of the return spring 800 near the movable block 610 is interference-fitted with the fixing protrusion 613.

[0091] In this embodiment, the end of the return spring 800 near the movable block 610 is interference-fitted with the fixed protrusion 613, so that the end of the return spring 800 near the movable block 610 is fixed relative to the movable block 610 and will not move or rotate.

[0092] As shown in Figures 3 and 5, based on the above embodiment, the spring seat 700 is provided with an oil passage hole 730, which is distributed along the axial direction of the spring seat 700 and penetrates the middle of the spring seat 700.

[0093] In this embodiment, the oil passage holes 730 are distributed along the axial direction of the spring seat 700 and penetrate through the middle of the spring seat 700, allowing engine oil to pass through the spring seat 700.

[0094] Specifically, the oil passage 730 is located inside the positioning protrusion 720 of the spring seat 700, so the oil passing through the oil passage can be guided directly into the return spring 800.

[0095] In addition, the outer periphery of the spring seat 700 can be configured as a "petal" shape or a tooth shape to facilitate the flow of oil through the outer periphery of the spring seat 700.

[0096] As shown in Figures 1, 2, 4, and 6, based on the above-described embodiment, a limiting unit is also included. The limiting unit is disposed on one of the intake rocker arm 300 and the movable block 610, and can contact the other of the intake rocker arm 300 and the movable block 610, thereby limiting the separation of the movable block 610 from the intake rocker arm 300.

[0097] Specifically, the limiting unit can be a limiting edge provided in one of the intake rocker arm 300 and the movable block 610, and can contact the other of the intake rocker arm 300 and the movable block 610 as the two move relative to each other, or it can be other structures. The specific structure of the limiting unit is not limited here, as long as it can restrict the movable block 610 from separating from the rocker arm.

[0098] As shown in Figures 1, 2, 4, and 6, based on the above-described embodiment, the limiting unit includes a limiting pin 900, which is disposed on the movable block 610 and can contact the air intake rocker arm 300.

[0099] In this embodiment, the limiting pin 900 can contact the intake rocker arm 300, thereby restricting the separation of the movable block 610 from the intake rocker arm 300, and also preventing the movable block 610 from falling out of the intake rocker arm 300 when the intake valve 1200 flies off due to abnormal engine operation.

[0100] As shown in Figures 1, 2, and 6, based on the above embodiment, the movable block 610 is provided with an internal thread (not shown in the figure), and the limiting pin 900 is provided with an external thread (not shown in the figure). The limiting pin 900 and the movable block 610 are threadedly connected through the external thread and the internal thread.

[0101] In this embodiment, the limiting pin 900 and the movable block 610 are connected by an external thread and an internal thread, thereby realizing a detachable connection between the limiting pin 900 and the movable block 610.

[0102] As shown in Figures 1, 2, and 4, based on the above-described embodiment, the intake rocker arm 300 is further provided with a limiting groove 330, and the limiting pin 900 can contact the intake rocker arm 300 through the limiting groove 330.

[0103] In this embodiment, the limiting groove 330 can limit the limiting pin 900 to prevent relative slippage of the limiting pin 900 when it contacts the intake rocker arm 300 due to the slope of the contact position, so that the limiting pin 900 always falls in the limiting groove 330 to achieve contact with the intake rocker arm 300.

[0104] Example 2

[0105] As shown in Figure 8, an intake valve late-closing device includes: a camshaft 100, a rocker arm shaft 200, an intake rocker arm 300, a main roller 400, a control unit 500, a movable unit, and a clearance spring 1000.

[0106] As shown in Figures 1 to 8, the difference between Embodiment 2 and Embodiment 1 is that Embodiment 1 has a contact part and a return spring 800, while Embodiment 2 does not have a contact part and a return spring 800, but instead has a stop spring 1000.

[0107] One end of the clearance spring 1000 is connected to the intake rocker arm 300, and the other end of the return spring 800 is in contact with the movable block 610. The return spring 800 pushes the movable block 610 closer to the intake rocker arm 300 along the axial direction of the movable hole 320, thereby forming a clearance gap between the intake valve 1200 closing roller 620 and the intake rocker arm 300.

[0108] When the solenoid valve is closed, the intake cam 110 contacts the main roller 400 and drives the intake rocker arm 300 to swing around the rocker arm shaft 200 through the main roller 400.

[0109] When the solenoid valve is opened, the engine oil enters the movable hole 320 through the control unit 500 and drives the movable block 610 to move away from the intake rocker arm 300 along the axial direction of the movable hole 320, thereby eliminating the clearance and separating the intake cam 110 from the main roller 400 to form a pause gap. The intake closing cam 120 contacts the intake valve 1200 closing roller 620 and drives the movable block 610 through the intake valve 1200 closing roller 620 to drive the intake rocker arm 300 to swing around the rocker arm shaft 200.

[0110] In this embodiment, the intake valve 1200 closing rocker arm in the prior art is eliminated. Instead, it is movably connected to the intake rocker arm 300 via a movable unit. When the solenoid valve is closed, the intake cam 110 contacts the main roller 400, and the avoidance spring 1000 pushes the intake valve 1200 closing roller 620 to separate from the intake valve 120. When the solenoid valve is open, the oil pressure pushes the movable block 610 to move away from the intake rocker arm 300, thereby causing the intake valve 120 to contact the intake valve 1200 closing roller 620 and separating the intake cam 110 from the main roller 400, forming a pause gap so that it no longer functions.

[0111] Example 3

[0112] As shown in Figure 9, an intake valve assembly includes an intake valve late-closing device as described in Embodiment 1, and further includes an intake valve bridge 1100 and an intake valve 1200. A valve gap is formed between the intake valve bridge 1100 and the intake rocker arm 300. The intake rocker arm 300 can contact the intake valve bridge 1100, and the intake valve 1200 is connected to the intake valve bridge 1100.

[0113] When the solenoid valve is closed, the intake cam 110 contacts the main roller 400 and drives the intake rocker arm 300 to swing around the rocker arm shaft 200 through the main roller 400, thereby eliminating the valve clearance and driving the intake valve bridge 1100 to open the intake valve 1200.

[0114] When the solenoid valve is opened, the intake valve closing cam 120 contacts the intake valve closing roller 620 and drives the movable block 610 to drive the intake rocker arm 300 to swing around the rocker arm shaft 200, thereby eliminating the valve clearance and driving the intake valve bridge 1100 to open the intake valve 1200.

[0115] In this embodiment, when the solenoid valve is closed, the intake valve assembly achieves the intake stroke by contacting the intake cam 110 with the main roller 400; when the solenoid valve is open, the intake valve assembly achieves the intake valve 1200 closing stroke by contacting the intake valve 1200 closing roller 620 with the intake valve 1200 closing roller.

[0116] As shown in Figure 9, based on the above embodiment, the intake rocker arm 300 is further provided with an adjusting bolt 340. The valve clearance is formed between the adjusting bolt 340 and the intake valve bridge 1100. The adjusting bolt 340 is used to adjust the size of the valve clearance. The intake rocker arm 300 can contact the intake valve bridge 1100 through the adjusting bolt 340.

[0117] In this embodiment, the intake rocker arm 300 can contact the intake valve bridge 1100 through the adjusting bolt 340. The valve clearance can be adjusted by adjusting the adjusting bolt 340 in advance, thereby changing the intake stroke to the late closing stroke of the intake valve 1200.

[0118] Example 4

[0119] As shown in Figure 10, an intake valve assembly includes an intake valve late-closing device as described in Embodiment 2, and the other structures of Embodiment 4 are the same as those of Embodiment 3.

[0120] Example 5

[0121] An engine including an intake valve assembly as described in Embodiment 3 or Embodiment 4.

Claims

1. An intake valve late-closing device, characterized in that, include: Camshaft, which includes intake camshaft and intake closing camshaft; The rocker arm shaft has its axis direction parallel to that of the camshaft. An intake rocker arm is fitted with the rocker arm shaft through a shaft hole. The intake rocker arm can swing back and forth around the rocker arm shaft. The intake rocker arm is provided with a movable hole that communicates with the outside. The intake rocker arm includes a main roller and a movable unit. The main roller is rotatably connected to the intake rocker arm, the main roller and the intake rocker arm are fixed relative to each other, and the main roller can contact the intake cam; The movable unit includes a movable block and an intake valve late-closing roller. The movable block is located at the end of the movable hole near the outside and can move along the axis of the movable hole to achieve a disengagement function. The intake valve late-closing roller is rotatably connected to the movable block and can contact the intake valve late-closing cam.

2. The intake valve late-closing device as described in claim 1, characterized in that: It also includes a contact part and a return spring. When the movable block moves to a position away from the intake rocker arm, the intake cam separates from the main roller and forms a pause gap. The contact part is connected to the intake rocker arm and located in the movable hole. One end of the return spring contacts the movable block, and the other end of the return spring contacts the contact part. The return spring pushes the movable block away from the intake rocker arm along the axial direction of the movable hole. The intake valve closing cam can contact the intake valve closing roller.

3. The intake valve late-closing device as described in claim 2, characterized in that: The contact part is configured as a spring seat, which is perpendicular to the moving direction of the movable block. At least a portion of the spring seat is connected to the air intake rocker arm, and one end of the return spring is in contact with the spring seat.

4. The intake valve late-closing device as described in claim 3, characterized in that: The spring seat is provided with a first contact surface, which is perpendicular to the moving direction of the movable block. The return spring has a spiral structure and is provided with a second contact surface, which is perpendicular to the moving direction of the movable block and contacts the first contact surface.

5. The intake valve late-closing device as described in claim 4, characterized in that: The movable block is provided with a third contact surface, which is perpendicular to the moving direction of the movable block. The return spring has a spiral structure and is provided with a fourth contact surface, which is perpendicular to the moving direction of the movable block and contacts the third contact surface.

6. An intake valve late-closing device as described in any one of claims 2-5, characterized in that: The spring seat is provided with a positioning protrusion, which is located on the side of the spring seat near the return spring. The end of the return spring near the spring seat is sleeved on the positioning protrusion and is interference-fitted with the positioning protrusion.

7. An intake valve late-closing device as described in any one of claims 2-5, characterized in that: The movable block is provided with a positioning recess, which is located on the side of the movable block near the return spring, and the end of the return spring near the movable block is embedded in the positioning recess.

8. The intake valve late-closing device as described in claim 7, characterized in that: The positioning recess is provided with a fixing protrusion, which is located on the inner periphery of the positioning recess near the bottom. The inner diameter of the fixing protrusion is smaller than the inner diameter of the positioning recess. The end of the return spring near the movable block is interference-fitted with the fixing protrusion.

9. The intake valve late-closing device as described in claim 3, characterized in that: The spring seat is provided with oil passage holes, which are distributed along the axial direction of the spring seat and pass through the middle of the spring seat.

10. The intake valve late-closing device as described in claim 1, characterized in that: It also includes a limiting unit, which is disposed on one of the intake rocker arm and the movable block, and can contact the other of the intake rocker arm and the movable block, thereby limiting the separation of the movable block from the intake rocker arm.

11. The intake valve late-closing device as described in claim 10, characterized in that: The limiting unit includes a limiting pin, which is disposed on the movable block and can contact the intake rocker arm.

12. The intake valve late-closing device as described in claim 11, characterized in that: The movable block is provided with an internal thread, and the limiting pin is provided with an external thread. The limiting pin and the movable block are threadedly connected through the external thread and the internal thread.

13. The intake valve late-closing device as described in claim 11, characterized in that: The intake rocker arm is also provided with a limiting groove, and the limiting pin can contact the intake rocker arm through the limiting groove.

14. The intake valve late-closing device as described in claim 1, characterized in that: It also includes a clearance spring, one end of which is connected to the intake rocker arm, and the other end of which contacts the movable block. The clearance spring pushes the movable block closer to the intake rocker arm along the axial direction of the movable hole, thereby forming a clearance gap between the intake valve closing roller and the intake rocker arm. When the movable block moves to a position away from the intake rocker arm, the clearance gap is eliminated and the intake cam is separated from the main roller, forming a pause gap.

15. An intake valve assembly, characterized in that, The device includes an intake valve late-closing device as described in any one of claims 1 to 14, further comprising: an intake valve bridge and an intake valve, wherein a valve clearance is formed between the intake valve bridge and the intake rocker arm, the intake rocker arm can contact the intake valve bridge, and the intake valve is connected to the intake valve bridge.

16. An intake valve assembly as claimed in claim 15, characterized in that: The intake rocker arm is also provided with an adjusting bolt, and the valve clearance is formed between the adjusting bolt and the intake valve bridge. The adjusting bolt is used to adjust the size of the valve clearance, and the intake rocker arm can contact the intake valve bridge through the adjusting bolt.

17. An engine, characterized in that, Including an intake valve assembly as described in claim 15.