Electro-hydraulic composite retarder with straight blade structure

Abstract

The invention relates to the technical field of automobile auxiliary braking, and discloses an electro-hydraulic composite retarder with a straight blade structure, which comprises a rotor, a stator, a stator connecting piece and a magnet exciting coil. The rotor is of a double-tooth type structure, radial blades and semicircular hydraulic circulation liquid channels are arranged on the two end faces of the rotor, and salient pole teeth are arranged on the outer circumferential end face of the rotor. A hydraulic circulation liquid channel matched with the rotor liquid channel is formed in the end face of the stator, and a hydraulic working cavity is formed; the stator connecting piece is of a hollow cylinder structure, the two ends of the stator connecting piece are fixedly connected with the left stator and the right stator respectively, and a liquid outlet is formed. The excitation coil is fixed on the inner side of the stator connecting piece and located at an axial gap of rotor teeth, the rotor and the stator connecting piece are made of magnetic and conductive materials, the synergistic effect of hydraulic braking and eddy current braking is achieved, and the composite retarder which is high in braking power density at the full-speed section, fast in response, compact in structure and convenient to machine and assemble is obtained.

Description

Technical Field

[0001] This invention belongs to the field of automotive auxiliary braking technology, specifically relating to an electro-hydraulic composite retarder with a straight blade structure. Background Technology

[0002] A retarder is an auxiliary braking device installed in the transmission system of a commercial vehicle. It is primarily used during long downhill slopes or continuous braking conditions to convert the vehicle's kinetic energy into heat energy and dissipate it through a non-frictional method, thereby reducing vehicle speed or maintaining a constant speed and mitigating the risk of brake fade. Existing retarders include hydraulic retarders and eddy current retarders, among others.

[0003] Eddy current retarders offer fast response and good low-speed braking performance, but their braking power density decreases at high speeds due to the skin effect, and braking heat is mainly concentrated in the eddy current components, resulting in high heat dissipation pressure. Hydraulic retarders offer strong high-speed braking capability and do not rely on vehicle electrical energy, but their low-speed braking power density is relatively low and their response is relatively slow.

[0004] Therefore, there is an urgent need for a composite retarder that is compact, easy to manufacture and assemble, can maintain a high braking power density across the entire speed range, and also has a fast response. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the problems of high-speed braking attenuation and heat load concentration in existing eddy current retarders, and insufficient low-speed braking and slow response in hydraulic retarders. This invention provides an electro-hydraulic composite retarder that can achieve synergy between hydraulic braking and eddy current braking and is suitable for all speed range conditions.

[0006] To achieve the above objectives, the present invention provides an electro-hydraulic composite retarder with a straight blade structure, comprising a rotor, a stator, a stator connector, and an excitation coil; The stator includes a left stator and a right stator. The outer circumferential end faces of the rotor are provided with salient pole teeth. Both end faces of the rotor are provided with radial blades and a semi-circular hydraulic circulation channel between the blades. The left stator and the right stator are provided with a semi-circular hydraulic circulation channel two that cooperates with the semi-circular hydraulic circulation channel one on the side near the rotor, and together with the radial blades on the rotor end face, they form a hydraulic working chamber after assembly. The stator connector is sleeved on the outside of the rotor, and the excitation coil is a disc-shaped coil, fixed inside the stator connector, and located between the left and right convex pole teeth of the rotor.

[0007] Preferably, the rotor and stator connector is made of a magnetic and conductive material. When the excitation coil is energized with DC current, the magnetic flux forms a closed magnetic circuit through the stator connector, the rotor salient pole teeth and the air gap between them, and a strong magnetic field is formed in the air gap between the tip of the rotor salient pole teeth and the inner wall of the stator connector, so as to induce eddy currents in the inner wall of the stator connector and generate an eddy current braking torque.

[0008] Preferably, both the left and right stators are provided with liquid inlets, which extend from the outside of the stator into its interior and communicate with the hydraulic working chamber. Both the left and right stators are provided with two liquid inlets, one on the upper side and one on the lower side.

[0009] Preferably, the upper part of the stator connector is provided with a first liquid outlet and a second liquid outlet. The first liquid outlet and the second liquid outlet are respectively connected to the left hydraulic working chamber and the right hydraulic working chamber inward, and are both connected to the vehicle coolant circuit inward.

[0010] Preferably, the tooth grooves and / or fluid channels of the rotor form a flow channel connecting the hydraulic working chamber and the air gap region, so that a portion of the working fluid can flow from the hydraulic working chamber to the air gap region between the rotor salient pole tooth tip and the inner wall of the stator connector, so as to carry away the eddy current heat of the inner wall of the stator connector and then be discharged through the outlet.

[0011] Preferably, the left stator and the right stator are made of aluminum alloy.

[0012] Preferably, the air gap between the outer cylindrical surface of the rotor and the inner wall of the stator connector is 0.5 mm to 2 mm.

[0013] Preferably, the hydraulic braking torque is adjusted by regulating the working fluid pressure and / or flow rate at the inlet and outlet; the eddy current braking torque is adjusted by regulating the excitation current of the excitation coil.

[0014] Preferably, the rotor is fixedly connected to the vehicle drive shaft by a key and rotates synchronously with the drive shaft, while the stator is fixed to the vehicle frame and does not rotate with it. A sealing ring is provided at the gap fit between the rotor and the left and right stators.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The same rotor structure can simultaneously handle both hydraulic and eddy current braking, achieving a high degree of structural integration and compact axial dimensions; 2. Hydraulic braking is suitable for medium- and high-speed, high-power ranges, while eddy current braking is suitable for low-speed, fast-response ranges. The two can be superimposed or switched to improve braking power density across the entire speed range. 3. The working fluid circuit removes hydraulic loss heat and eddy current heat, reducing the risk of local thermal degradation; 4. The blades have a straight blade structure, which facilitates the consistency control of processing, manufacturing and assembly. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of an electro-hydraulic composite retarder with a straight blade configuration; Figure 2 This is a diagram of the axial fluid passage of an electro-hydraulic composite retarder with a straight blade structure. Figure 3 This is a schematic diagram of the magnetic circuit of an electro-hydraulic composite retarder with a straight blade structure (arrows indicate the direction of the magnetic circuit). Figure 4 This is a three-dimensional structural diagram of the rotor; Figure 5 This is a schematic diagram of the left stator.

[0017] Reference numerals in the attached drawings: 1—rotor; 101—salient pole tooth; 2—stator connector; 201—first liquid outlet; 202—second liquid outlet; 3—left stator; 301—liquid inlet; 4—drive shaft; 5—excitation coil; 6—working fluid circuit; 7—magnetic circuit. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings. It should be noted that this embodiment is used to explain the present invention and not to limit it, and those skilled in the art can make equivalent substitutions without departing from the spirit of the present invention.

[0019] like Figure 1 As shown, the electro-hydraulic composite retarder with a straight blade structure of the present invention includes a rotor 1, a stator, a stator connector 2, and an excitation coil 5. The rotor 1 is fixedly connected to the vehicle drive shaft 4 by a key and rotates synchronously with the drive shaft, while the stator is fixed to the vehicle frame and does not rotate with it.

[0020] The stator includes a left stator 3 and a right stator, which are symmetrically arranged about the left and right symmetrical planes of the rotor 1. The left stator 3 is a disc-shaped component with a semi-circular hydraulic circulation channel on the side closest to the rotor 1, and radial blades evenly distributed along the circumference. The radial blades are straight blades. The right stator structure is symmetrically arranged with the left stator 3. The rotor 1 has a double-tooth structure, with straight blades and semi-circular hydraulic circulation channels on both ends of the rotor 1. After assembly, the straight blades on the rotor end faces and the corresponding stator blades together form a hydraulic working chamber, so that hydraulic deceleration units are formed on the left and right sides of the rotor.

[0021] The stator connector 2 is a hollow cylindrical structure with a smooth, continuous inner wall. It is fitted onto the outside of the rotor 1 and coaxial with it. Both ends of the stator connector 2 are fixedly connected to the outer edges of the left stator 3 and the right stator, respectively, thus reliably connecting the left and right stators to form an integral housing structure. The stator connector 2 has a first outlet 201 and a second outlet 202, which are connected to the return water pipe of the vehicle's coolant circuit. The left stator 3 has two inlets 301, one on the upper side and one on the lower side. These inlets extend from the outside to the inside and are connected to the hydraulic working chamber. The inlets can be connected in parallel to the bypass pipe of the vehicle's engine coolant circuit, allowing the working fluid to enter the retarder.

[0022] The excitation coil 5 is a disc-shaped coil, fixed to the outside of the stator connector 2, and located at the corresponding position in the axial gap of the rotor 1 tooth structure. The rotor 1 and the stator connector 2 are made of magnetically and electrically conductive material. When a direct current is applied to the excitation coil 5, the magnetic flux forms a closed magnetic circuit through the stator connector 2, the rotor salient pole teeth 101, and the air gap between them, and a strong magnetic field is formed in the air gap between the tip of the rotor salient pole teeth 101 and the inner wall of the stator connector 2. When the rotor 1 rotates relative to the stator connector 2, eddy currents are generated on the inner wall of the stator connector 2 under the action of the changing magnetic field. The interaction between the eddy currents and the magnetic field generates an eddy current braking torque, which hinders the rotation of the rotor 1 and thus achieves eddy current deceleration.

[0023] like Figure 2 As shown, the working fluid enters the hydraulic working chamber through the inlet 301. Driven by the rotor 1, it undergoes strong shearing and circulating flow with the stator blades, generating hydraulic braking torque. At the same time, the tooth grooves and / or fluid channels of the rotor 1 form a flow channel connecting the hydraulic working chamber and the air gap region, allowing a portion of the working fluid to flow to the air gap region between the tip of the rotor salient pole tooth 101 and the inner wall of the stator connector 2. After absorbing the eddy current heat generated by the inner wall of the stator connector 2, it is discharged through the first outlet 201 and the second outlet 202 and flows back to the vehicle radiator for heat dissipation, thereby improving continuous braking capability and reducing the risk of thermal fade.

[0024] In terms of control methods, hydraulic braking torque can be adjusted by regulating the pressure and / or flow rate at the inlet 301 and outlets 201 and 202; eddy current braking torque can be adjusted by regulating the excitation current of the excitation coil 5. The two braking methods can operate independently or be superimposed according to the vehicle speed range, gradient, and thermal load to obtain a wider speed range braking capability and faster response.

[0025] Furthermore, the left stator 3 and the right stator can be made of aluminum alloy to reduce the overall weight; the air gap between the outer cylindrical surface of the rotor 1 and the inner wall of the stator connector 2 is preferably 0.5 to 2 mm to balance electromagnetic efficiency and assembly tolerance.

Claims

1. An electro-hydraulic composite retarder with a straight blade structure, characterized in that, include: Rotor (1), stator, stator connector (2) and excitation coil (5); The stator includes a left stator (3) and a right stator. The outer circumferential end faces of the rotor (1) are provided with salient pole teeth (101). Both end faces of the rotor (1) are provided with radial blades and a semi-circular hydraulic circulation channel between the blades. The left stator (3) and the right stator are provided with a semi-circular hydraulic circulation channel II that cooperates with the semi-circular hydraulic circulation channel on the side near the rotor (1), and after assembly, they together with the straight blades on the end face of the rotor (1) form a hydraulic working chamber. The stator connector (2) is sleeved on the outside of the rotor (1), and the excitation coil (5) is a disc-shaped coil, fixed inside the stator connector (2), and located in the middle of the left and right convex pole teeth (101) of the rotor (1).

2. The electro-hydraulic composite retarder according to claim 1, characterized in that: The rotor (1) and stator connector (2) are made of magnetic and conductive materials. When the excitation coil (5) is supplied with DC current, the magnetic flux forms a closed magnetic circuit through the stator connector (2), the rotor salient pole teeth (101) and the air gap between them. A strong magnetic field is formed in the air gap between the tooth tip of the rotor salient pole teeth (101) and the inner wall of the stator connector (2) to induce eddy currents in the inner wall of the stator connector (2) and generate electric eddy current braking torque.

3. The electro-hydraulic composite retarder according to claim 1, characterized in that: Both the left and right stators are equipped with liquid inlets, which extend from the outside of the stator into its interior and communicate with the hydraulic working chamber. Both the left and right stators are equipped with two liquid inlets, one on the upper side and one on the lower side.

4. The electro-hydraulic composite retarder according to claim 1, characterized in that: The upper part of the stator connector (2) is provided with a first liquid outlet (201) and a second liquid outlet (202). The first liquid outlet (201) and the second liquid outlet (202) are respectively connected to the left hydraulic working chamber and the right hydraulic working chamber inward, and are connected to the vehicle coolant circuit inward.

5. The electro-hydraulic composite retarder according to claim 2, characterized in that: The tooth grooves and / or liquid channels of the rotor (1) form a flow channel connecting the hydraulic working chamber and the air gap region, so that a part of the working fluid can flow from the hydraulic working chamber to the air gap region between the tooth tip of the rotor salient pole tooth (101) and the inner wall of the stator connector (2) to carry away the eddy current heat of the inner wall of the stator connector (2) and then be discharged through the liquid outlet (201, 202).

6. The electro-hydraulic composite retarder according to any one of claims 1-5, characterized in that: The left stator (3) and the right stator are made of aluminum alloy.

7. The electro-hydraulic composite retarder according to any one of claims 1-5, characterized in that: The air gap between the outer cylindrical surface of the rotor (1) and the inner wall of the stator connector (2) is 0.5 mm to 2 mm.

8. The electro-hydraulic composite retarder according to any one of claims 1-5, characterized in that: The hydraulic braking torque is adjusted by regulating the working fluid pressure and / or flow rate at the inlet (301) and outlet (201, 202); the eddy current braking torque is adjusted by regulating the excitation current of the excitation coil (5).

9. The electro-hydraulic composite retarder according to any one of claims 1-5, characterized in that: The rotor (1) is fixedly connected to the vehicle drive shaft (4) by a key and rotates synchronously with the drive shaft. The stator is fixed to the frame and does not rotate with it. A sealing ring is provided at the intermittent contact point between the rotor (1) and the left stator (3) and the right stator.

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