Camshaft cam with continuously variable radius

Abstract

The invention discloses a camshaft cam with continuously variable radius, which comprises a cylinder cover, shaft body support frames, a camshaft, a valve rocker arm, a power shaft, a push rod, a support spring and a valve seat plate, the cylinder cover is fixedly mounted on an engine, the shaft body support frames are fixedly mounted at two ends of the cylinder cover, and the camshaft is rotatably mounted in the shaft body support frames; the valve rocker arm is fixedly installed on the surface of the air cylinder cover, and the power shaft is fixedly installed at one end of the air cylinder cover and meshed with the cam shaft. A valve seat plate is fixedly installed at the lower end of the push rod, and the push rod is installed in the cylinder cover valve in a sliding mode and supported through a supporting spring. By arranging the shaft body supporting frame, the cam shaft, the valve rocker arm and the power shaft, the problems that according to an existing cam shaft, the stroke of a valve cannot be dynamically adjusted, continuous stepless adjustment of the stroke of the valve cannot be achieved, and the adjustment response speed is low are solved.

Description

Technical Field

[0001] The present invention relates to the field of camshaft devices, and particularly to a camshaft cam with continuously variable radius. Background Art

[0002] The camshaft is one of the core components of the internal combustion engine valve train and is known as the "breathing commander" of the engine. It is usually made of high-strength alloy steel or cast iron, runs through the engine cylinder head or cylinder block, and is precisely machined on the surface with a series of cams and drive gears. The geometric profile of each cam is precisely designed. By cooperating with the valve rocker arm, tappet or direct drive mechanism, the rotational motion is converted into the linear motion of the valve, thereby accurately controlling the opening / closing timing, opening height and duration of the intake valve and exhaust valve. This process directly determines the "breathing efficiency" of the engine - that is, the smoothness of the mixture of air and fuel entering the cylinder and the exhaust of the burned exhaust gas after combustion, and further affects the power output, fuel economy, emission level and running smoothness of the engine.

[0003] However, the traditional camshaft and the existing variable valve technologies have significant defects: their fixed cam profiles cannot dynamically adjust the valve stroke, resulting in poor adaptability of the engine operating conditions and difficulty in balancing low-speed torque and high-speed power; although the existing variable technologies achieve partial adjustment through hydraulic or mechanical structures, the systems are complex, costly, and only support limited gear positions or single-parameter adjustment, and cannot achieve continuous stepless adjustment of the valve stroke; in addition, the adjustment mechanisms relying on hydraulic or mechanical drive have problems of dynamic response lag and are difficult to meet the real-time requirements of transient operating conditions. These defects make it difficult for the existing technologies to achieve global dynamic optimization of the valve motion law under the premise of simplified structure and controllable cost, seriously restricting the improvement of engine efficiency and emission performance.

[0004] Therefore, it is very necessary to invent a camshaft cam with continuously variable radius. Summary of the Invention

[0005] The purpose of the present invention is to provide a camshaft cam with continuously variable radius to solve the problems that the existing camshaft still cannot dynamically adjust the valve stroke, cannot achieve continuous stepless adjustment of the valve stroke, and has a slow adjustment response speed.

[0006] To achieve the above object, the present invention provides the following technical solutions: It includes a cylinder head, a shaft support frame, a camshaft, a valve rocker arm, a power shaft, a push rod, a support spring and a valve seat plate. The cylinder head is fixedly installed on the engine, and the shaft support frame is fixedly installed at both ends of the cylinder head. The camshaft is rotatably installed inside the shaft support frame; the valve rocker arm is fixedly installed on the surface of the cylinder head, and the power shaft is fixedly installed at one end of the cylinder head and meshes with the camshaft; the lower end of the push rod is fixedly installed with a valve seat plate, and the push rod is slidably installed inside the cylinder head valve and is supported by a support spring.

[0007] The shaft support frame includes a sliding bracket, an upper cover of the sliding base, a support bearing and an adjustment push rod. The sliding bracket is fixedly installed at both ends of the cylinder head, and the sliding base is slidably installed on the sliding bracket; the upper cover is fixedly installed above the sliding base, and the support bearing is fixedly installed inside the sliding base and the upper cover. The camshaft is fixedly installed inside the support bearing.

[0008] The camshaft includes a support shaft body, a driving cam, a stroke adjustment slope, a meshing gear and a fixing bolt. The support shaft body is rotatably installed inside the support bearing, and the driving cam is fixedly installed on the surface of the support shaft body; the stroke adjustment slope is fixedly installed on one side of the driving cam, and the meshing gear is fixedly installed at one end of the support shaft body through a fixing bolt.

[0009] The valve rocker arm includes a mounting bracket, a driving rocker arm, a connecting shaft, a force-receiving ball and a force-applying ball. The mounting bracket is fixedly installed on the surface of the cylinder head, and the driving rocker arm is rotatably installed outside the mounting bracket through a connecting shaft; the force-receiving ball is rotatably installed at one end of the driving rocker arm, and the force-applying ball is rotatably installed at the other end of the driving rocker arm.

[0010] The power shaft includes an extension arm, a rotating table, a driving gear and an input shaft. The extension arm is fixedly installed at one end of the cylinder head, and the rotating table is fixedly installed at one end of the extension arm; the driving gear is rotatably installed on the rotating table and meshes with the meshing gear; the input shaft is fixedly installed at one end of the driving gear.

[0011] The sliding brackets inside the shaft support frame are made of two mutually parallel steel metal frames, and the sliding base can slide on the sliding brackets. The upper cover fixes the support bearing inside it and the sliding base to form a bearing seat; the bearing seats formed by the upper cover of the sliding base and the support bearing are in four groups and are connected into one body by brackets through the expansion positions above the upper cover; the support bearing enables the camshaft to rotate; the adjustment push rod connects the first group of sliding bases to the cylinder head and can push the shaft support frame and the camshaft to move reciprocally.

[0012] The entire camshaft can rotate inside the shaft support frame and can move along with the movement of the shaft support frame; the support shaft body is made of a steel metal shaft, and the driving cams are made of several steel metal cams. The stroke adjustment slope is the slope on one side of the driving cam; the stroke adjustment slope makes the size of the driving cam gradually smaller through its own slope; the driving cam and the stroke adjustment slope can, through the movement of the entire camshaft, bring different-sized areas of themselves into contact with the valve rocker arm; the meshing gear is a long strip-shaped gear, and when the meshing gear moves horizontally along the camshaft, it can always mesh with the power shaft through its longer size.

[0013] The driving rocker arm inside the valve rocker arm is a lever structure, and the driving rocker arm can transmit the force generated by the camshaft and act on the push rod to control the opening and closing of the valve seat plate; the force-receiving ball and the force-applying ball are two steel metal wheels, and annular slopes are provided at both ends of the force-receiving ball and the force-applying ball. The slopes at both ends of the force-receiving ball and the force-applying ball can cooperate with the driving cam and the stroke adjustment slope. When the force-receiving ball contacts the driving cam, the stroke of the valve seat plate is the specified stroke. When the force-receiving ball contacts the stroke adjustment slope, the opening stroke of the valve will gradually decrease.

[0014] The driving gear inside the power shaft is connected to the power source through the input shaft to generate rotation, and meshes with the camshaft to make the camshaft rotate.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] 1. The setting of the shaft support frame of the present invention fixes and supports the camshaft through the support bearing to ensure its stable rotation; the horizontal reciprocating movement of the camshaft is realized through the sliding bracket and the sliding base, thereby changing the contact area between the driving cam and the valve rocker arm and adjusting the valve opening stroke; at the same time, the push rod is adjusted to push the sliding base to move, further controlling the change of the cam radius. In addition, the shaft support frame maintains the overall stability through multiple sets of bearing seat structures and transmits power through the meshing of the meshing gear with the power shaft to drive the camshaft to rotate. It is the core component for support, adjustment, and power transmission.

[0017] 2. The setting of the camshaft of the present invention contacts the valve rocker arm through the driving cam to convert the rotational motion into a linear motion, driving the push rod to control the opening and closing of the valve seat plate, thereby adjusting the valve movement; at the same time, the stroke adjustment slope on the camshaft cooperates with the sliding adjustment function of the shaft support frame, enabling different areas of the driving cam to contact the valve rocker arm, realizing the continuously variable cam radius and the adjustment of the valve opening stroke; in addition, the camshaft meshes with the driving gear of the power shaft through the meshing gear to receive and transmit power, ensuring the synchronism and accuracy of the valve movement; finally, the camshaft rotates stably in the support bearing through the support shaft body and moves along with the shaft support frame. It is the key component for driving, adjusting, and supporting the valve movement.

[0018] 3. The valve rocker arm of the present invention is arranged to convert the rotational motion of the camshaft into linear motion through the driving rocker arm, and transmit the force to the push rod to control the opening and closing of the valve seat plate; meanwhile, the force receiving ball of the valve rocker arm contacts the driving cam or the stroke adjustment slope, and adjusts the valve opening stroke through the change of the contact area; in addition, the valve rocker arm adopts a lever structure and is supported by a connecting shaft to accurately transmit the force, ensuring the accuracy and reliability of the valve movement; finally, the annular slope design of the force receiving ball and the force applying ball can adapt to the continuous change of the cam radius, ensuring the smoothness of the valve movement. It is the core component for transmitting motion, adjusting the stroke and adapting to changes.

[0019] 4. The power shaft of the present invention is arranged such that the rotational motion of the external power source is transmitted to the camshaft through the meshing of the driving gear and the meshing gear of the camshaft, driving its rotation and providing power for the valve movement; meanwhile, the power shaft is fixedly installed on the cylinder head through the extension arm and the rotating table to ensure its working stability; in addition, the meshing design of the power shaft and the camshaft ensures the synchronization of their rotational motions, enabling the precise coordination of valve opening and closing; finally, the power shaft is connected to the external power source through the input shaft, inputting power into the camshaft system. It is the core component for transmitting power, supporting and fixing, achieving synchronization and connecting the power source. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of the front of the present invention.

[0021] Figure 2 It is a schematic structural diagram of the bottom of the present invention.

[0022] Figure 3 It is a schematic structural diagram of the second perspective of the present invention.

[0023] Figure 4 It is a schematic structural diagram of the shaft body support frame of the present invention.

[0024] Figure 5 It is a schematic structural diagram of the camshaft of the present invention.

[0025] Figure 6 It is a schematic structural diagram of the valve rocker arm of the present invention.

[0026] Figure 7 It is a schematic structural diagram of the power shaft of the present invention.

[0027] In the figure:

[0028] Cylinder head 1, shaft body support frame 2, camshaft 3, valve rocker arm 4, power shaft 5, push rod 6, support spring 7, valve seat plate 8, sliding bracket 21, sliding base 22, upper end gland 23, support bearing 24, adjustment push rod 25, support shaft body 31, drive cam 32, stroke adjustment slope 33, meshing gear 34, fixing bolt 35, mounting bracket 41, drive rocker arm 42, connecting shaft 43, force pellet 44, force - applying pellet 45, extension arm 51, rotating table 52, drive gear 53 and input shaft 54. Detailed implementation mode

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0030] As shown in the attached Figure 1-7 figure:

[0031] A cam of a camshaft with continuously variable radius provided by the present invention includes a cylinder head 1, a shaft body support frame 2, a camshaft 3, a valve rocker arm 4, a power shaft 5, a push rod 6, a support spring 7 and a valve seat plate 8. The cylinder head 1 is fixedly installed on the engine, and the shaft body support frame 2 is fixedly installed at both ends of the cylinder head 1. The camshaft 3 is rotatably installed inside the shaft body support frame 2; the valve rocker arm 4 is fixedly installed on the surface of the cylinder head 1, and the power shaft 5 is fixedly installed at one end of the cylinder head 1 and meshes with the camshaft 3; the lower end of the push rod 6 is fixedly installed with a valve seat plate 8, and the push rod 6 is slidably installed inside the valve of the cylinder head 1 and is supported by the support spring 7.

[0032] The shaft body support frame 2 includes a sliding bracket 21, a sliding base 22, an upper end gland 23, a support bearing 24 and an adjustment push rod 25. The sliding bracket 21 is fixedly installed at both ends of the cylinder head 1, and the sliding base 22 is slidably installed on the sliding bracket 21; the upper end gland 23 is fixedly installed above the sliding base 22, and the support bearing 24 is fixedly installed inside the sliding base 22 and the upper end gland 23. The camshaft 3 is fixedly installed inside the support bearing 24.

[0033] The camshaft 3 includes a support shaft body 31, a drive cam 32, a stroke adjustment slope 33, a meshing gear 34 and a fixing bolt 35. The support shaft body 31 is rotatably installed inside the support bearing 24, and the drive cam 32 is fixedly installed on the surface of the support shaft body 31; the stroke adjustment slope 33 is fixedly installed on one side of the drive cam 32, and the meshing gear 34 is fixedly installed at one end of the support shaft body 31 through the fixing bolt 35.

[0034] The valve rocker arm 4 includes a mounting bracket 41, a driving rocker arm 42, a connecting shaft 43, a force-receiving ball 44 and a force-applying ball 45. The mounting bracket 41 is fixedly installed on the surface of the cylinder head 1, and the driving rocker arm 42 is rotatably installed on the outside of the mounting bracket 41 through the connecting shaft 43; the force-receiving ball 44 is rotatably installed at one end of the driving rocker arm 42, and the force-applying ball 45 is rotatably installed at the other end of the driving rocker arm 42.

[0035] The power shaft 5 includes an extension arm 51, a rotating table 52, a driving gear 53 and an input shaft 54. The extension arm 51 is fixedly installed at one end of the cylinder head 1, and the rotating table 52 is fixedly installed at one end of the extension arm 51; the driving gear 53 is rotatably installed on the rotating table 52 and meshes with the meshing gear 34; the input shaft 54 is fixedly installed at one end of the driving gear 53.

[0036] The sliding bracket 21 inside the shaft body support frame 2 is composed of two mutually parallel steel metal frames, and the sliding base 22 can slide on the sliding bracket 21. The upper end gland 23 fixes the support bearing 24 inside it and the sliding base 22 to form a bearing seat; the bearing seats formed by the sliding base 22, the upper end gland 23 and the support bearing 24 are in four groups and are connected into one body by the extension positions above the upper end gland 23 through the bracket; the support bearing 24 can make the camshaft 3 rotate; the adjustment push rod 25 connects the first group of sliding bases 22 with the cylinder head 1 and can push the shaft body support frame 2 and the camshaft 3 to move reciprocally.

[0037] The entire camshaft 3 can rotate inside the shaft body support frame 2 and can move along with the movement of the shaft body support frame 2; the support shaft body 31 is a steel metal shaft, and the driving cams 32 are several steel metal cams. The stroke adjustment slope 33 is a slope on one side of the driving cam 32; the stroke adjustment slope 33 makes the size of the driving cam 32 gradually smaller through its own slope; the driving cam 32 and the stroke adjustment slope 33 can make different-sized areas of themselves contact the valve rocker arm 4 through the overall movement of the camshaft 3; the meshing gear 34 is a long-strip-shaped out-wheel, and when the camshaft 3 moves horizontally, the meshing gear 34 can always mesh with the power shaft 5 through its longer size.

[0038] The driving rocker arm 42 inside the valve rocker arm 4 is a lever structure, and the driving rocker arm 42 can transmit the force generated by the camshaft 3 and act on the push rod 6 to control the opening and closing of the valve seat plate 8; the force-receiving ball 44 and the force-applying ball 45 are two steel metal wheels, and annular slopes are provided at both ends of the force-receiving ball 44 and the force-applying ball 45. The slopes at both ends of the force-receiving ball 44 and the force-applying ball 45 can cooperate with the driving cam 32 and the stroke adjustment slope 33. When the force-receiving ball 44 contacts the driving cam 32, the stroke of the valve seat plate 8 is the specified stroke. When the force-receiving ball 44 contacts the stroke adjustment slope 33, the stroke of the valve opening will gradually decrease.

[0039] The driving gear 53 inside the power shaft 5 is connected to the power source through the input shaft 54 to generate rotation, and meshes with the camshaft 3 to make the camshaft 3 rotate.

[0040] This camshaft cam structure with continuously variable radius realizes precise control of the valve opening stroke by dynamically adjusting the cam radius. The working principle is as follows:

[0041] 1. Power input and transmission: The external power source drives the power shaft 5 to rotate through the input shaft 54. The driving gear 53 of the power shaft 5 meshes with the meshing gear 34 of the camshaft 3 to transmit the power to the camshaft 3 and make it rotate synchronously.

[0042] 2. Camshaft rotation and valve drive: When the camshaft 3 rotates, the driving cam 32 on its surface contacts the force-receiving ball 44 of the valve rocker arm 4, pushing the valve rocker arm 4 to swing around the connecting shaft 43; the valve rocker arm 4 transmits the force to the push rod 6 through the lever action, driving the valve seat plate 8 to move up and down to realize the opening and closing of the valve.

[0043] 3. Continuously variable cam radius: The camshaft 3 is provided with a stroke adjustment slope 33. When the shaft body support frame 2 pushes the sliding base 22 to move horizontally through the adjustment push rod 25, the whole camshaft 3 moves accordingly; as the camshaft 3 moves, different areas of the driving cam 32 and the stroke adjustment slope 33 contact the valve rocker arm 4, changing the valve opening stroke. When the force-receiving ball 44 contacts the driving cam 32, the valve opening stroke is larger; when contacting the stroke adjustment slope 33, the valve opening stroke gradually decreases.

[0044] 4. Precise control of valve movement: Annular slopes are provided at both ends of the force-receiving ball 44 and the force-applying ball 45 of the valve rocker arm 4, which can smoothly cooperate with the driving cam 32 and the stroke adjustment slope 33 to ensure the smoothness and precision of the valve movement; the support spring 7 provides a resilience when the valve is closed to ensure that the push rod 6 and the valve seat plate 8 are reset in time.

[0045] 5. Synchronization and stability: The meshing design of the power shaft 5 and the camshaft 3 ensures the synchronization of their rotational movements, enabling the opening and closing of the valves to be precisely matched with the engine working cycle; the shaft body support frame 2, through the bearing seat structure composed of multiple groups of sliding bases 22, upper end caps 23, and support bearings 24, ensures the stability of the camshaft 3 during rotation and movement.

[0046] Summary: The cam structure of this camshaft transmits power through the power shaft 5 to drive the rotation of the camshaft 3. Utilizing the dynamic changes of the driving cam 32 and the stroke adjustment slope 33, combined with the lever action of the valve rocker arm 4, continuous adjustment of the valve opening stroke is achieved. At the same time, components such as the shaft body support frame 2 and the support spring 7 ensure the stability and precision of the system, making it suitable for engine application scenarios that require dynamic adjustment of the valve stroke.

[0047] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A cam of a camshaft with continuously variable radius, comprising a cylinder head (1), a shaft body support frame (2), a camshaft (3), a valve rocker arm (4), a power shaft (5), a push rod (6), a support spring (7) and a valve seat plate (8). The cylinder head (1) is fixedly installed on the engine, and the shaft body support frame (2) is fixedly installed at both ends of the cylinder head (1). The camshaft (3) is rotatably installed inside the shaft body support frame (2); the valve rocker arm (4) is fixedly installed on the surface of the cylinder head (1), and the power shaft (5) is fixedly installed at one end of the cylinder head (1) and meshes with the camshaft (3); the lower end of the push rod (6) is fixedly installed with a valve seat plate (8), and the push rod (6) is slidably installed inside the valve of the cylinder head (1) and is supported by the support spring (7).

2. The cam of a camshaft with continuously variable radius according to claim 1, wherein: The shaft body support frame (2) includes a sliding bracket (21), a sliding base (22), an upper end gland (23), a support bearing (24) and an adjustment push rod (25). The sliding bracket (21) is fixedly installed at both ends of the cylinder head (1), and the sliding base (22) is slidably installed on the sliding bracket (21); the upper end gland (23) is fixedly installed above the sliding base (22), and the support bearing (24) is fixedly installed inside the sliding base (22) and the upper end gland (23). The camshaft (3) is fixedly installed inside the support bearing (24).

3. The cam of a camshaft with continuously variable radius according to claim 1, characterized in that: The camshaft (3) includes a support shaft body (31), a drive cam (32), a stroke adjustment slope (33), a meshing gear (34) and a fixing bolt (35). The support shaft body (31) is rotatably installed inside the support bearing (24), and the drive cam (32) is fixedly installed on the surface of the support shaft body (31); the stroke adjustment slope (33) is fixedly installed on one side of the drive cam (32), and the meshing gear (34) is fixedly installed at one end of the support shaft body (31) through the fixing bolt (35).

4. A cam of a camshaft with continuously variable radius according to claim 1, characterized in that: The valve rocker arm (4) includes a mounting bracket (41), a drive rocker arm (42), a connecting shaft (43), a force-receiving ball (44) and a force-applying ball (45). The mounting bracket (41) is fixedly installed on the surface of the cylinder head (1), and the drive rocker arm (42) is rotatably installed outside the mounting bracket (41) through the connecting shaft (43); the force-receiving ball (44) is rotatably installed at one end of the drive rocker arm (42), and the force-applying ball (45) is rotatably installed at the other end of the drive rocker arm (42).

5. A cam of a camshaft with continuously variable radius according to claim 1, characterized in that: The power shaft (5) includes an extension arm (51), a rotating table (52), a drive gear (53) and an input shaft (54). The extension arm (51) is fixedly installed at one end of the cylinder head (1), and the rotating table (52) is fixedly installed at one end of the extension arm (51); the drive gear (53) is rotatably installed on the rotating table (52) and meshes with the meshing gear (34); the input shaft (54) is fixedly installed at one end of the drive gear (53).

6. A cam of a camshaft with continuously variable radius as claimed in claim 2, characterized in that: The sliding bracket (21) inside the shaft body support bracket (2) is composed of two parallel steel metal frames, and the sliding base (22) can slide on the sliding bracket (21). The upper end gland (23) fixes the support bearing (24) inside it and the sliding base (22) to form a bearing seat; Four groups of bearing seats formed by the sliding base (22), the upper end gland (23) and the support bearing (24) are connected into one body by the extension position above the upper end gland (23) through a bracket; The support bearing (24) enables the camshaft (3) to rotate; The adjusting push rod (25) connects the first group of sliding bases (22) to the cylinder head (1), and can push the shaft body support bracket (2) and the camshaft (3) to move reciprocally.

7. A cam of a camshaft with continuously variable radius as claimed in claim 3, characterized in that: The entire camshaft (3) can rotate inside the shaft body support bracket (2) and can move along with the movement of the shaft body support bracket (2); The support shaft body (31) is a steel metal shaft, and the driving cams (32) are several steel metal cams. The stroke adjustment slope (33) is a slope on one side of the driving cam (32); The stroke adjustment slope (33) makes the size of the driving cam (32) gradually smaller through its own slope; The driving cam (32) and the stroke adjustment slope (33) can, through the overall movement of the camshaft (3), make different sized areas of themselves contact the valve rocker arm (4); The meshing gear (34) is a long strip-shaped gear, and when the camshaft (3) moves horizontally, the meshing gear (34) can always mesh with the power shaft (5) through its longer size.

8. A cam of a camshaft with continuously variable radius according to claim 4, characterized in that: The driving rocker arm (42) inside the valve rocker arm (4) is a lever structure, and the driving rocker arm (42) can transmit the force generated by the camshaft (3) and act on the push rod (6) to control the opening and closing of the valve seat plate (8); The force receiving ball (44) and the force applying ball (45) are two steel metal wheels, and annular slopes are provided at both ends of the force receiving ball (44) and the force applying ball (45). The slopes at both ends of the force receiving ball (44) and the force applying ball (45) can cooperate with the driving cam (32) and the stroke adjustment slope (33). When the force receiving ball (44) contacts the driving cam (32), the stroke of the valve seat plate (8) is the specified stroke. When the force receiving ball (44) contacts the stroke adjustment slope (33), the opening stroke of the valve will gradually decrease.

9. A cam of a camshaft with continuously variable radius as claimed in claim 5, characterized in that: The driving gear (53) inside the power shaft (5) is connected to a power source through the input shaft (54) to generate rotation and meshes with the camshaft (3) to make the camshaft (3) rotate.

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