CN106968788A - A kind of variable compression ratio of engines device - Google Patents

Abstract

The invention relates to a variable compression ratio device for an engine. The two eccentric wheels are respectively set in the piston hole seat, the piston pin passes through the two eccentric wheels and the small head of the large connecting rod, and each of the two eccentric wheels is equipped with a small connecting rod with an interference fit with the eccentric wheel and a chute. There is a connecting rod reinforcing rib extending to both sides in the middle of the large connecting rod. The hydraulic plunger is installed in the hole groove on both sides of the connecting rod reinforcing rib through threads, and the sliding pin passes through the sliding pin chute on the small connecting rod through interference fit. Installed in the small hole on the plunger rod, so that the sliding pin can slide in the chute driven by the plunger rod, and drive the small connecting rod to swing, so that the eccentric sleeve rotates, so that the piston is at the top dead center or The position relative to the cylinder at the bottom dead center is changed, and then the compression ratio is changed.

Description

A variable compression ratio device for an engine

technical field

The present invention relates to an automobile engine, and more particularly, the present invention relates to a variable compression ratio connecting rod device capable of changing its compression ratio according to the driving condition of the engine.

Background technique

The compression ratio of the engine refers to the ratio of the cylinder volume when the piston moves to the bottom dead center and the cylinder volume when the piston moves to the top dead center. Increasing the compression ratio can effectively improve the performance and efficiency of the engine. Because the pressure increases, the density of the gas increases, and the distance between the molecules becomes smaller, so that the distance between the fuel molecules and the oxygen molecules is closer, and the combustion speed is faster; the pressure increases to increase the temperature in the cylinder, which can The gas molecules move faster, the fuel molecules and oxygen molecules interact more easily, and the mixed gas is easier to ignite. Moreover, the smaller combustion space can complete the combustion faster, and the faster combustion process also improves the performance. An excessively high compression ratio will increase the frequency of knocking, and a high compression ratio puts forward higher requirements on the quality of fuel. To solve this problem, the variable compression ratio engine can change the compression ratio of the engine in real time, so that the engine uses a high compression ratio to improve the thermal efficiency and fuel economy of the engine under low and medium load conditions; A low compression ratio prevents knocking.

The use of variable compression ratio technology can:

1. Improve the thermal efficiency of the engine and improve the fuel economy of the engine;

2. Suitable for multi-fuel drive;

3. Help reduce emissions;

4. Improve engine running stability;

5. On the premise of ensuring the power performance, the engine displacement can be further reduced, the structure is more compact, and the specific mass is higher.

Contents of the invention

The object of the present invention is to provide a connecting rod with infinitely variable compression ratio of an internal combustion engine by changing the connecting rod mechanism of the engine.

In order to solve the problems of the technologies described above, the present invention is achieved by adopting the following technical solutions:

A variable compression ratio device for an engine, comprising piston pin 1, piston body 2, piston hole seat I3, eccentric sleeve I snap ring I4, eccentric sleeve I5, piston pin snap ring I6, small connecting rod I7, sliding pin slide Groove Ⅰ8, sliding pin Ⅰ head 9, sliding pin Ⅰ10, plunger main body Ⅰ11, connecting rod reinforcement 12, large connecting rod 13, oil supply channel 14, plunger main body Ⅱ15, sliding pin Ⅱ16, sliding pin Ⅱ head 17 , sliding pin chute Ⅱ18, small connecting rod Ⅱ19, piston hole seat Ⅱ20, eccentric sleeve Ⅱ21, piston pin snap ring Ⅱ22, eccentric sleeve snap ring Ⅱ23, large connecting rod small head 24, limit block Ⅰ25, plunger rod I26, sealing ring I27, plunger spring I28, thread 29 and hole groove 30.

The variable compression ratio device of the engine is characterized in that: the eccentric sleeve I5 and the eccentric sleeve II21 are respectively sleeved in the piston hole seat I3 and the piston hole seat II20, and are in clearance fit with the piston hole seat, and the piston pin 1 Pass through the eccentric sleeve Ⅰ5, eccentric sleeve Ⅱ21 and the small end 24 of the large connecting rod, and cooperate with the two eccentric sleeves and the small end 24 of the large connecting rod. The eccentric sleeve Ⅰ5 and the eccentric sleeve Ⅱ21 connect Dalian The small rod head 24 is sandwiched in the middle, and the piston pin snap ring I6, the piston pin snap ring II22, the eccentric sleeve I snap ring 4, and the eccentric sleeve II snap ring 23 connect the piston pin 1 with the eccentric sleeve I5 and the eccentric sleeve II21 limit.

The variable compression ratio device of the engine is characterized in that: the upper ends of the small connecting rod I7 and the small connecting rod II19 are respectively set on the eccentric sleeve I5 and the eccentric sleeve II21, and the small connecting rod and the eccentric sleeve For interference fit, the middle and lower parts of the small connecting rod Ⅰ7 and the small connecting rod Ⅱ19 are provided with sliding pin chute Ⅰ8, sliding pin chute Ⅱ18, sliding pin Ⅰ10, sliding pin Ⅱ16 and sliding pin chute Ⅰ8, sliding pin chute respectively Ⅱ18 has a clearance fit and can slide in the chute, and the diameter of the head 9 of the sliding pin I and the head 17 of the sliding pin II is larger than the width of the chute, thereby limiting the position of the sliding pin, and the diameter of the other end of the sliding pin I10 and the other end of the sliding pin II16 The same diameter as the slide pin to allow the slide pin to pass through the slide pin slot.

The variable compression ratio device of the engine is characterized in that the sliding pin I10 is in interference fit with the small hole in the head of the plunger rod I26, so that the sliding pin I10 can pass through the sliding pin chute and be fixedly connected. On the plunger rod I26, a connecting rod reinforcing rib 12 connected with the large connecting rod is added in the middle of the large connecting rod 13. At the left end of the reinforcing rib, there is a hole on the left end of the plunger main body I11 and the connecting rod reinforcing rib 12. The internal and external threads on I30 are connected with I29, the hydraulic oil passes through the oil supply channel 14 on the large connecting rod 13, passes through the oil chamber opened on the connecting rod reinforcement rib 12, and finally reaches the hydraulic plunger, and the plunger spring I28 pushes the plunger The plug rod I14 is connected to the wall of the plunger body I11, and the limit block I25 is connected to the plunger body I11 through nuts and bolts. At the same time, the seal ring I27 reduces the leakage of high-pressure oil; similarly, the structure at the right end of the connecting rod reinforcement rib 12 And the connection method is the same as the left end.

Description of drawings

Below in conjunction with accompanying drawing, the present invention will be further described:

Fig. 1 is a structural cross-sectional view of a variable compression ratio device for an engine according to the present invention;

Fig. 2 is a schematic diagram of the engine variable compression ratio device according to the present invention;

Fig. 3 is a cross-sectional view of the engine variable compression ratio device according to the present invention cut from A in Fig. 1;

Fig. 4 is a comparison diagram of the piston position before and after the hydraulic plunger works in the engine variable compression ratio device according to the present invention.

In the figure, 1 piston pin, 2 piston body, 3 piston hole seat Ⅰ, 4 eccentric sleeve Ⅰ snap ring Ⅰ, 5 eccentric sleeve Ⅰ, 6 piston pin snap ring Ⅰ, 7 small connecting rod Ⅰ, 8 sliding pin chute Ⅰ, 9 sliding pin Ⅰ head, 10 sliding pin Ⅰ, 11 plunger main body Ⅰ, 12 connecting rod reinforcement rib, 13 large connecting rod, 14 oil supply channel, 15 plunger main body Ⅱ, 16 sliding pin Ⅱ, 17 sliding pin Ⅱ head, 18 sliding pin chute Ⅱ, 19 small connecting rod Ⅱ, 20 piston hole seat Ⅱ, 21 eccentric sleeve Ⅱ, 22 piston pin snap ring Ⅱ, 23 eccentric sleeve snap ring Ⅱ, 24 large connecting rod small head , 25 limit block Ⅰ, 26 plunger rod Ⅰ, 27 sealing ring Ⅰ, 28 plunger spring Ⅰ, 29 thread and 30 hole groove.

detailed description

Below in conjunction with accompanying drawing, the present invention is described in detail variable compression ratio working principle:

See Figure 1:

The eccentric sleeve I5 and the eccentric sleeve II21 are respectively sleeved in the piston hole seat I3 and the piston hole seat II20, and are matched with the piston hole seat in clearance, that is, the eccentric sleeve can rotate in the piston hole seat.

The piston pin 1 passes through the eccentric sleeve I5, the eccentric sleeve II21 and the small end 24 of the large connecting rod, and cooperates with the two eccentric sleeves and the small end 24 of the large connecting rod, that is, the two eccentric sleeves and the small end of the large connecting rod are small. The head can rotate around the piston pin.

Eccentric sleeve Ⅰ5, eccentric sleeve Ⅱ21 clamp the small end 24 of the large connecting rod in the middle, and piston pin snap ring Ⅰ6, piston pin snap ring Ⅱ22 and eccentric sleeve Ⅰ snap ring 4, eccentric sleeve Ⅱ snap ring 23 hold the piston The pin 1 is limited by the eccentric sleeve I5 and the eccentric sleeve II21 so that it cannot move left and right.

The upper ends of the small connecting rod I7 and the small connecting rod II19 are respectively set on the eccentric sleeve I5 and the eccentric sleeve II21. The small connecting rod and the eccentric sleeve are interference fit, that is, the swing of the two small connecting rods can drive the eccentric wheel Piston bore rotation.

After the eccentric sleeve I5 and the eccentric sleeve II21 rotate, the position of the piston pin relative to the piston hole is changed, and then the piston is displaced upward or downward relative to the piston pin, so that the piston is at the top dead center and the bottom dead center. The position of the cylinder changes.

The middle and lower parts of the small connecting rod Ⅰ7 and the small connecting rod Ⅱ19 are provided with sliding pin chute Ⅰ8 and sliding pin chute Ⅱ18, and sliding pin Ⅰ10 and sliding pin Ⅱ16 are clearance fit with sliding pin chute Ⅰ8 and sliding pin chute Ⅱ18 respectively and can Slide in the chute, and the diameter of the head 9 of the sliding pin I and the head 17 of the sliding pin II are larger than the width of the chute, thereby limiting the position of the sliding pin, ensuring that the sliding pin will not pass through the chute, and the sliding pin The diameter of the other end of I10 and the sliding pin II16 is the same as that of the sliding pin, so that the sliding pin can pass through the sliding groove.

Refer to Figure 1 and Figure 3:

The interference fit between the sliding pin I10 and the small hole in the head of the plunger rod I26 allows the sliding pin I10 to pass through the sliding pin chute and be fixed to the plunger rod I26, so that when the plunger rod stretches, the sliding pin It also moves together, so that the sliding pin slides on the sliding pin chute, and then drives the rotation of the small connecting rod.

In the middle of the large connecting rod 13, there is a connecting rod reinforcing rib 12 integrated with the large connecting rod. At the left end of the reinforcing rib, the internal and external threads of the hole I30 on the plunger main body I11 and the left end of the connecting rod reinforcing rib 12 I29 is connected.

The hydraulic oil passes through the oil supply channel 14 on the connecting rod 13, passes through the oil cavity opened on the connecting rod rib 12, and finally reaches the hydraulic plunger. The plunger spring I28 connects the plunger rod I14 to the wall of the plunger body I11. When the hydraulic oil pump is not working, the plunger rod I26 on the side of the connecting rod rib 12 is pulled back to the initial position under the tension of the plunger spring I28; when the hydraulic oil pump is working, the plunger rod I26 is pushed by the hydraulic oil It moves outward, and the pressure limiting valve can control the size of the oil pressure, so that the plunger rod remains fixed at any position within the stroke.

The limit block I25 is connected with the plunger main body I11 through nuts and bolts, and the sealing ring I27 reduces the leakage of high-pressure oil; similarly, the structure and connection method of the right end of the connecting rod rib 12 is the same as that of the left end.

See Figure 4:

The upper half of the large connecting rod, the small connecting rod and the hydraulic plunger form a right-angled triangle. The upper half of the large connecting rod and the hydraulic plunger are two right-angled sides of the right-angled triangle. The length is constant, that is, there is a fixed right-angle side. When the length of the hydraulic plunger is constant, the length of the two right-angle sides is fixed. From the Pythagorean theorem, the length of the hypotenuse is also constant, so the length of the small connecting rod remains unchanged. That is to say, the position of the sliding pin in the chute remains unchanged. At this time, the small connecting rod will not drive the eccentric sleeve to rotate, and the compression ratio will not be changed. When the compression ratio needs to be changed, the high-pressure oil pump will work, and the high-pressure oil will push the hydraulic plunger to move. When it is extended to a certain position, the plunger pushes the small connecting rod to rotate, thereby driving the eccentric sleeve to rotate, so that the position of the piston relative to the cylinder is changed, and the compression ratio is changed.

Claims (4)

1. An engine variable compression ratio device, including piston pin (1), piston body (2), piston hole seat I (3), eccentric sleeve I snap ring I (4), eccentric sleeve I (5) , Piston pin snap ring Ⅰ (6), small connecting rod Ⅰ (7), sliding pin chute Ⅰ (8), sliding pin Ⅰ head (9), sliding pin Ⅰ (10), plunger main body Ⅰ (11) , connecting rod reinforcing rib (12), large connecting rod (13), oil supply channel (14), plunger body II (15), sliding pin II (16), sliding pin II head (17), sliding pin slide Groove II (18), small connecting rod II (19), piston hole seat II (20), eccentric sleeve II (21), piston pin snap ring II (22), eccentric sleeve snap ring II (23), large Connecting rod small end (24), limit block I (25), plunger rod I (26), sealing ring I (27), plunger spring I (28), thread (29) and hole groove (30). 2. The engine variable compression ratio device according to claim 1, characterized in that: the eccentric sleeve I (5) and the eccentric sleeve II (21) are respectively set on the piston hole seat I (3), the piston The hole seat II (20) is in clearance fit with the piston hole seat, the piston pin (1) passes through the eccentric sleeve I (5), the eccentric sleeve II (21) and the small end of the large connecting rod (24), And cooperate with the two eccentric sleeves and the small end of the large connecting rod (24) in clearance, the eccentric sleeve I (5) and the eccentric sleeve II (21) clamp the small end of the large connecting rod (24) in the middle, and at the same time the piston pin is stuck Ring I (6), piston pin snap ring II (22) and eccentric sleeve I snap ring (4), eccentric sleeve II snap ring (23) connect piston pin (1) with eccentric sleeve I (5), eccentric Sleeve II (21) limit. 3. The engine variable compression ratio device according to claim 1, characterized in that: the upper ends of the small connecting rod I (7) and the small connecting rod II (19) are respectively sleeved on the eccentric sleeve I (5) On the eccentric sleeve II (21), the small connecting rod and the eccentric sleeve are in an interference fit, and the middle and lower parts of the small connecting rod I (7) and the small connecting rod II (19) are provided with sliding pin chute I (8) , sliding pin chute II (18), sliding pin I (10), sliding pin II (16) are clearance fit with sliding pin chute I (8), sliding pin chute II (18) respectively and can fit in the chute Sliding, and the diameter of the head of sliding pin I (9) and the head of sliding pin II (17) is larger than the width of the chute, so that the sliding pin is limited, and the other end of sliding pin I (10) and sliding pin II (16) The diameter is the same as that of the slide pin, allowing the slide pin to pass through the slide pin slot. 4. The engine variable compression ratio device according to claim 1, characterized in that: the sliding pin I (10) is in interference fit with the small hole in the head of the plunger rod I (26), so that The sliding pin I (10) passes through the sliding pin chute and is fixed to the plunger rod I (26). A connecting rod reinforcing rib (12) is added in the middle of the large connecting rod (13) to connect with the large connecting rod. At the left end of the reinforcing rib, the plunger main body I (11) is connected with the internal and external threads I (29) on the hole groove I (30) opened on the left end of the connecting rod reinforcing rib (12), and the hydraulic oil passes through the large connecting rod The oil supply channel (14) on (13) passes through the oil chamber opened on the connecting rod reinforcement rib (12), and finally reaches the hydraulic plunger, and the plunger spring I (28) connects the plunger rod I (14) to the column The plug main body I (11) is connected to the wall, and the limit block I (25) is connected to the plunger main body I (11) through nuts and bolts. At the same time, the sealing ring I (27) reduces the leakage of high-pressure oil; similarly, the connecting rod The structure and connection mode of reinforcing rib (12) right-hand side are identical with left-hand side.