CN104806376A - Beta-type Stirling engine with three-crank crankshaft for magnetic driving - Google Patents

Abstract

The invention relates to a β-type Stirling engine with three crankshaft magnetic drive. Including heater, cylinder block, piston, connecting rod mechanism, crankshaft, body, magnetic drive and generator; thermal mechanism is composed of heater, cylinder block, hot piston, cold piston and regenerator; connecting rod mechanism includes a Hot connecting rod and two cold connecting rods; the crankshaft is a three-crank crankshaft, with 3 crank journals and 4 crank discs; the fully enclosed magnetic drive power output mechanism consists of a body, a magnetic drive and a generator. The invention has compact structure and coordinated movement of all components, which can not only maintain the running stability of the cold piston, reduce the additional lateral force of the piston, but also ensure that the movement of the hot piston is ahead of the crank angle of the cold piston by 90 degrees, and improve the effective power output. The built-in trough type regenerator improves the heat recovery efficiency, and the fully enclosed magnetic drive power output mechanism can eliminate the friction loss caused by dynamic sealing.

Description

β-type Stirling engine with three crankshaft magnetic drive

technical field

The invention belongs to the field of engine technology, and in particular relates to a Stirling engine.

Background technique

Automobiles have become an important part of modern society. While bringing convenience to human society, automobiles consume huge oil resources. The temperature of automobile exhaust is high, which has a high value of waste heat utilization. At present, the exhaust of automobiles at home and abroad is directly discharged into the atmosphere. There is a huge amount of automobiles in my country, and it is not only a huge waste of energy to directly discharge automobile exhaust into the atmosphere, but also cause serious environmental pollution.

The Stirling engine is an external combustion closed cycle reciprocating piston heat engine. Its ideal thermodynamic cycle is called the Stirling cycle (that is, the generalized Carnot cycle). Under the same temperature conditions, its theoretical Highest efficiency. It has two characteristics that are obviously superior to internal combustion engines: one is that it can use various energy sources, whether it is commonly used liquid fuel, gas fuel or solid fuel, etc., as long as it can generate heat at a certain temperature, the Stirling engine can work. Little dependence on oil resources. Second, because there is no combustion process in the internal combustion engine in the Stirling engine, the pressure changes smoothly and the vibration noise is low. There is no intake and exhaust process in the Stirling engine, and the working medium is a closed cycle, so no harmful emissions are produced and it has good environmental characteristics.

Using the waste heat of automobile exhaust as a high-temperature heat source to drive the engine to perform mechanical work, the low-grade exhaust heat can be converted into high-grade mechanical energy, thereby improving the energy quality. Therefore, the present invention's research on the automobile exhaust waste heat Stirling engine has very important strategic significance and great engineering value for improving the oil resource utilization rate of my country's automobiles.

The structural types of the Stirling engine mainly include three types: α, β and γ, among which the β type has the most compact structure. At present, the practical types of β-type transmission mechanisms mainly include crank-connecting rod mechanisms, diamond-shaped transmission mechanisms, and free-piston transmission mechanisms. Among them, the technology of the crank-link mechanism is mature, the mechanism is relatively simple, and the phase difference between the hot and cold chambers is easy to ensure, but the balance is poor. The β-type gas distribution Stirling engine usually uses a two-crank mechanism, which makes the mechanism run less smoothly. The rhombus mechanism has four connecting rods connected with two connecting rods according to the length ratio, so that its shape is close to rhombus and it runs smoothly, but the mechanism is relatively complicated. The free piston mechanism is simple, but it is not suitable to ensure the phase difference between the volume of the hot chamber and the volume of the cold chamber.

At present, Stirling engines in the world are all in closed cycle working mode, which must be sealed with a special sealing structure to prevent leakage of working fluid. Leakage of working fluid is a common failure phenomenon of Stirling engines, and it is also one of the most difficult problems to solve. The leakage of the working medium will cause the power and efficiency of the engine to drop, the engine cannot work normally, and the whole machine will be damaged if it is serious. The sealing structure is not only technically difficult, but also makes the engine structure complicated, the machine heavy, the friction loss is large, and the operation reliability is poor. This is also one of the main reasons why the Stirling engine is difficult to be widely applied in the engineering field.

Contents of the invention

In order to overcome the shortcomings of the traditional Stirling engine, such as difficult sealing, complex structure, heavy machine, large friction loss and poor operation reliability, the present invention is the first to propose a β-type Stirling engine with a three-crank crankshaft magnetic transmission structure through improvement. Lin engine, through a reasonable engine structure design, can transmit the rotational motion of the crankshaft to the outside of the crankcase without contact, and can reduce heat shuttle loss and heat conduction loss, ensure smooth engine operation, greatly reduce friction loss, and improve engine thermal efficiency.

The β-type Stirling engine with three crankshaft crankshaft magnetic drive includes a heater 1, a cylinder block 21, a piston, a connecting rod mechanism, a crankshaft 12, a body 7, a magnetic drive 10 and a generator 11;

The upper part of the cylinder block 21 is a hot chamber 2, and the lower part is a cold chamber 18; the heater 1 is arranged on the hot chamber 2, and the outer side of the cold chamber 18 is provided with a cooling jacket 6, and the heater 1 and the A regenerator 19 is provided on the inner wall of the cylinder block 21 between the cooling jackets 6, and a gas channel is formed between the regenerator 19 and the inner wall of the cylinder block 21; the piston is divided into a hot piston 3 and a cold piston 5, and the hot piston 3 Coaxially located above the cold piston 5, and corresponding to the heater 1; the heater 1, the cylinder block 21, the hot piston 3, the cold piston 5 and the regenerator 19 form a thermal mechanism;

The connecting rod mechanism includes a hot connecting rod 9 and two cold connecting rods 8; the crankshaft 12 is a three-crank crankshaft, the two ends of which are main journals 1204, and the three bell cranks in the middle are respectively a hot connecting rod Journal 1202 and two cold connecting rod journals 1201; the connecting rod mechanism and the crankshaft form a three-crank crankshaft mechanism;

The lower end of the cylinder block 21 is connected to the body, which is a sealed chamber; the main journals 1204 at both ends of the crankshaft 12 are arranged in the buffer chamber 14 through bearings; the main journal 1204 at one end of the crankshaft 12 is connected to the generator 11 through the magnetic drive 10; The body corresponding to the other end of the crankshaft 12 is provided with an inflation joint 13;

The heater 1 converts the inhaled heat into mechanical work on the cold piston 5 to realize the cycle work of the β-type Stirling engine.

The cooling jacket 6 is in the shape of a cylindrical tube, and its outer cylindrical surface is in the shape of fins.

The regenerator 19 is in the shape of a cylindrical tube, and through grooves are evenly distributed on the outer cylindrical surface along the axial direction, and a gas channel is formed between the evenly distributed through grooves on the regenerator 19 and the inner wall of the cylinder block 21 .

The axial middle part of described cold piston 5 is provided with through hole, and hot piston straight rod 15 passes through this through hole; Be provided with sealing ring 4 between hot piston straight rod 15 and cold piston 5; The piston 3 is connected, and the lower end is connected with the upper end of the hot connecting rod 9; the lower end of the hot connecting rod 9 is connected with the hot connecting rod journal 1202 of the crankshaft; The cold connecting rods 8 are connected; the lower ends of the two cold connecting rods 8 are respectively connected with two cold connecting rod journals 1201 of the three-crank crankshaft 12 .

The middle part of the three crankshaft crankshaft is the hot connecting rod journal 1202, the two sides of the hot connecting rod journal 1202 are respectively connected to the cold connecting rod journal 1201 through the bellcrank disc, and the cold connecting rod journals 1201 on both sides are coaxial The outer sides of the cold connecting rod journals 1201 on both sides are respectively connected to the main journal 1204 through crank discs; the crank angle difference between the hot connecting rod journal 1202 and the cold connecting rod journal 1201 is 90 degrees.

The body is an inverted T-shaped tubular body, which are respectively an upright cavity and a horizontal cavity; the upright cavity is a buffer cavity 14, and the buffer cavity 14 is connected to the lower end of the cylinder block 21; the main journals 1204 at both ends of the crankshaft 12 pass through the bearing Set in the horizontal cavity.

The magnetic drive 10 is a planar magnetic coupling consisting of two parts, one part is fixedly connected to one end of the crankshaft 12 and rotates synchronously with the crankshaft, and the other part is fixedly connected to the generator 11 to make the rotational movement of the crankshaft 12 contactless. The ground is transmitted outwards so that the generator 11 can generate electricity.

Beneficial technical effect of the present invention is embodied in the following aspects:

(1) The design of the built-in regenerator used in the present invention, the regenerator is built in the upper part of the cylinder block, between the heater and the cooling jacket, and the outside of the cylinder block is covered with a heat insulation layer for heat insulation, so that the regenerator has The shortest heat transfer path can greatly reduce heat dissipation loss, significantly improve heat recovery efficiency, and then improve heat energy utilization efficiency.

(2) The present invention adopts a three-crankshaft design, which has three bellcrank journals (one hot connecting rod journal, two cold connecting rod journals) and four bellcrank discs. The hot connecting rod journal is located in the middle of the crankshaft, and is hinged with the hot piston straight rod through the hot connecting rod; the two cold connecting rod journals are located at both sides of the crankshaft, and are respectively hinged with two cold piston straight rods through two cold connecting rods. Two cold piston straight rods are symmetrically connected to the same cold piston. This structure can maintain the smooth operation of the cold piston, while reducing the additional lateral force of the piston and improving the effective power output.

(3) The three-crank crankshaft mechanism of the present invention can work in coordination with the hot piston and the cold piston parts in the thermal mechanism to ensure that the motion of the hot piston is 90 degrees ahead of the crank angle of the cold piston, and the phase angle between the two pistons Maintain at 90 degrees. The 90-degree piston phase angle can maximize the working ability of the gas working fluid, which in turn helps to improve the conversion efficiency of heat energy.

(4) The power output part of the present invention is designed with a planar magnetic coupling. The planar magnetic coupling consists of two parts, one part is installed at one end of the crankshaft and rotates synchronously with the crankshaft, and the other part is connected with the generator outside the crankcase. The rotation of the crankshaft inside the engine body can be transmitted to the outside of the engine body without contact, so that the generator can generate electricity. Since the crankcase and the atmospheric environment outside the box are in a static and fully enclosed state, there is no dynamic sealing link, which completely eliminates the friction loss caused by the dynamic sealing between the working fluid pressure and the atmospheric pressure of the current Stirling engine, and can greatly improve the effective power output of the engine. .

Description of drawings

Fig. 1 is a three-dimensional schematic diagram of the front structure of the present invention after the cylinder is cut away.

Fig. 2 is a schematic perspective view of the top view structure of the regenerator drawn out from the upper part of the cylinder block.

Figure 3 is a schematic diagram of the structure of the crankshaft with three crankshafts.

Serial numbers in the above picture: heater 1, hot chamber 2, hot piston 3, sealing ring 4, cold piston 5, cooling jacket 6, sealing body 7, cold connecting rod 8, hot connecting rod 9, magnetic drive 10, generator 11. Three bell crank crankshaft 12, cold connecting rod journal 1201, hot connecting rod journal 1202, bell crank disc 1203, three bell crank spindle 1204, air charging joint 13, buffer chamber 14, hot piston straight rod 15, cold piston straight rod Rod 16, cold piston seal ring 17, cold chamber 18, regenerator 19, heat insulation layer 20, cylinder block 21.

Detailed ways

The present invention will be further described through the embodiments below in conjunction with the accompanying drawings.

Referring to FIG. 1 , a β-type Stirling engine with three crankshaft magnetic drive includes a heater 1 , a cylinder block 21 , a piston, a connecting rod mechanism, a crankshaft 12 , a body 7 , a magnetic drive 10 and a generator 11 .

The upper part of the cylinder block 21 is a hot chamber 2, and the lower part is a cold chamber 18; the heater 1 is fixedly installed on the hot chamber 2, and a cooling jacket 6 is installed on the outside of the cold chamber 18. The cooling jacket 6 is cylindrical and tubular, and its outer cylindrical surface is finned. A regenerator 19 is installed on the inner wall of the cylinder block 21 between the heater 1 and the cooling jacket 6. The regenerator 19 is in the shape of a cylindrical tube. A gas passage is formed between the through groove of the cloth and the inner wall of the cylinder block 21, see FIG. 2 . The piston is divided into a hot piston 3 and a cold piston 5. The hot piston 3 is coaxially located above the cold piston 5 and corresponds to the heater 1; the heater 1, the cylinder block 21, the hot piston 3, the cold piston 5 and the regenerator 19 constitute a thermal mechanism.

The connecting rod mechanism includes a hot connecting rod 9 and two cold connecting rods 8; referring to Fig. 3, the crankshaft 12 is a three-crank crankshaft, wherein two ends are main journals 1204, the middle part is a hot connecting rod journal 1202, and the hot connecting rod The two sides of the journal 1202 are respectively connected to the cold connecting rod journal 1201 through the crank disc, and the cold connecting rod journals 1201 on both sides are coaxial; the outer sides of the cold connecting rod journal 1201 are respectively connected to the main shaft through the crank disc neck 1204; the crank angle difference between the hot connecting rod journal 1202 and the cold connecting rod journal 1201 is 90 degrees; the connecting rod mechanism and the crankshaft form a three-crank crankshaft mechanism.

The axial middle part of the cold piston 5 is provided with a through hole, and the hot piston straight rod 15 passes through the through hole; a sealing ring 4 is installed between the hot piston straight rod 15 and the cold piston 5; The lower end is connected with the upper end of the hot connecting rod 9; the lower end of the hot connecting rod 9 is connected with the hot connecting rod journal 1202 of the crankshaft; the upper ends of two cold piston straight rods 16 are connected with the cold piston 5, and the lower ends are respectively connected with two cold connecting The rods 8 are connected; the lower ends of the two cold connecting rods 8 are respectively connected with two cold connecting rod journals 1201 of the crankshaft crankshaft 12 .

The lower end of the cylinder block 21 is connected to the body; the body is a sealed cavity, in the shape of an inverted T-shaped tube, which are respectively an upright cavity and a horizontal cavity; the upright cavity is a buffer cavity 14, and the buffer cavity 14 is connected to the lower end of the cylinder block 21; The main journals 1204 at both ends of the crankshaft 12 are installed in the horizontal cavity through bearings; the main journals 1204 at one end of the crankshaft 12 are connected to the generator 11 through the magnetic driver 10; the magnetic driver 10 is a planar magnetic coupling, consisting of two parts, the One part is fixedly connected to one end of the crankshaft 12 and rotates synchronously with the crankshaft, and the other part is fixedly connected to the generator 11, and an air charging joint 13 is installed on the body corresponding to the other end of the crankshaft 12.

The heater 1 converts the absorbed heat into mechanical work for the cold piston 5 to realize the cycle work of the β-type Stirling engine.

The working principle of the present invention is as follows:

The gas working medium circulates in the heater 1 , the hot chamber 2 , the regenerator 19 and the cold chamber 18 . After the gas working medium absorbs external heat in the heater 1, the temperature rises and expands. On the one hand, it pushes the thermal piston 3 downward, which increases the volume of the hot chamber 2. On the other hand, the high-temperature working medium flows into cold cavity18. The hot piston 3 is also called a gas distribution piston, because its upper and lower end pressures are the same, and there is no exchange of power with the outside world. The regenerator 19 is built in the upper part of the cylinder block 21 and surrounds the hot piston 3. The gas working medium can alternately go down and up through the grooves on the regenerator 19 to release and absorb heat. After entering the cold chamber 18, the high-pressure gas working medium pushes the cold piston 5 to go down, and drives the crank connecting rod mechanism to output mechanical work to the outside. During the descending process of the cold piston 5, the working fluid dissipates heat to the outside through the cooling jacket 6 in the cold chamber 18, and the temperature drops. The cold piston 5 goes up after reaching the bottom dead center, and pushes the working fluid in the cold chamber 18 to absorb heat back into the hot chamber 2 through the regenerator 19 and absorb heat from the heater 1 again.

The mechanic obtained by the crankshaft linkage mechanism is externally output by the magnetic drive 10 . The magnetic drive 10 is in the form of a planar magnetic coupling and consists of two parts, one part is installed at one end of the three crankshaft main shaft and rotates synchronously with the crankshaft, and the other part is connected with the external generator 11 of the crankcase, so that The rotational motion of the crankshaft is transmitted to the outside of the engine body without contact, so that the generator 11 can generate electricity.

The present invention adopts cooling jacket air cooling. If the present invention is used for high-power equipment, a water-cooled tube cooler can also be used.

Claims (7)

1. the β type Stirling engine of three crank throw bent axle magnetic drives, comprises heater (1), cylinder block (21), piston, linkage mechanism, bent axle (12), body (7), magnetic driver (10) and generator (11), it is characterized in that:

The top of described cylinder block (21) is hot chamber (2), and bottom is cold chamber (18); Described heater (1) is located on hot chamber (2), the outside of described cold chamber (18) is arranged with coolant jacket (6), cylinder block (21) inwall between described heater (1) and coolant jacket (6) is provided with regenerator (19), and forms gas channel between regenerator (19) and cylinder block (21) inwall; Described piston is divided into hot piston (3) and cold piston (5), and hot piston (3) is coaxially positioned at the top of cold piston (5), and correspond to heater (1); Described heater (1), cylinder block (21), hot piston (3), cold piston (5) and regenerator (19) form heating power mechanism;

Described linkage mechanism comprises a hot connecting rod (9) and two cold connecting rods (8); Described bent axle (12) is three crank throw bent axles, and wherein two ends are main journal (1204), and three crank throws at middle part are respectively a hot rod journal (1202) and two cold rod journals (1201); Described linkage mechanism and bent axle form three crank throw crank mechanisms;

The lower end of cylinder block (21) is communicated with body, and body is Seal cage; The main journal (1204) at described bent axle (12) two ends is located in buffer cavity (14) by bearing; The main journal (1204) of bent axle (12) one end is connected to generator (11) by magnetic driver (10); The body corresponding with bent axle (12) the other end is provided with gas-charging connection (13);

The converting heat sucked is the mechanical work to cold piston (5) by described heater (1), realizes the periodic duty of β type Stirling engine.

2. the β type Stirling engine of three crank throw bent axle magnetic drives according to claim 1, it is characterized in that: described coolant jacket (6) is cylindrical tube, its external cylindrical surface is fin.

3. the β type Stirling engine of three crank throw bent axle magnetic drives according to claim 1, it is characterized in that: described regenerator (19) is cylindrical tube, uniformly vertically on external cylindrical surface offer groove, regenerator (19) is upper forms gas channel between uniform groove and cylinder block (21) inwall.

4. the β type Stirling engine of three crank throw bent axle magnetic drives according to claim 1, is characterized in that: the axis middle part of described cold piston (5) is provided with through hole, and hot straight rod piston (15) is through this through hole; Seal ring (4) is provided with between hot straight rod piston (15) and cold piston (5); Hot straight rod piston (15) upper end is connected with hot piston (3), and lower end is connected with the upper end of hot connecting rod (9); The lower end of hot connecting rod (9) is connected to the hot rod journal (1202) of bent axle; Two cold straight rod piston (16) upper ends are connected with cold piston (5), and lower end is connected with two cold connecting rods (8) respectively; The lower end of two cold connecting rods (8) respectively connected two cold rod journals (1201) of three crank throw bent axles (12).

5. the β type Stirling engine of three crank throw bent axle magnetic drives according to claim 1, it is characterized in that: the middle part of described three crank throw bent axles is hot rod journal (1202), the both sides of hot rod journal (1202) are connected to cold rod journal (1201) respectively by crank throw dish, and the cold rod journal (1201) of both sides is coaxial; Cold rod journal (1201) outside of both sides is connected to main journal (1204) respectively by crank throw dish; Described hot rod journal (1202) is 90 degree with the crank angle difference of described cold rod journal (1201).

6. the β type Stirling engine of three crank throw bent axle magnetic drives according to claim 1, is characterized in that: described body is the tubulose of inverted T-shaped, is respectively upright cavity and horizontal cavity; Upright cavity is buffer cavity (14), and buffer cavity (14) is communicated with the lower end of cylinder block (21); The main journal (1204) at described bent axle (12) two ends is located in horizontal cavity by bearing.

7. the β type Stirling engine of three crank throw bent axle magnetic drives according to claim 1, it is characterized in that: described magnetic driver (10) is plane magnetic coupling, be made up of two-part, one partial fixing is connected in bent axle (12) one end, rotate with crankshaft-synchronous, another part is fixedly connected generator (11), the rotary motion of bent axle (12) is contactlessly outwards transmitted, and makes generator (11) carry out power generation operation.