CN117175889B - Permanent-magnet retarder capable of automatically adjusting braking torque through air cooling - Google Patents

Abstract

The invention belongs to the technical field of auxiliary braking for heavy-duty vehicles, and relates to an air-cooled permanent magnet retarder that automatically adjusts braking torque. It includes a stator, and the stator includes a first conductor barrel and a conductor barrel bracket fixed to the vehicle. , the first conductor barrel is nested in the conductor barrel bracket; a transmission shaft, the transmission shaft includes an external spline shaft and a spring; the external spline shaft passes through the first conductor barrel and is connected with the There is a gap between the first conductor barrels that can accommodate the permanent magnet rotor, and the spring is sleeved on the external spline shaft; the permanent magnet rotor, the permanent magnet rotor is sleeved on the external spline shaft, And can move into the gap along the axial direction of the external spline shaft and press against the spring. The beneficial effect is that the permanent magnet rotor can automatically adjust the depth into the stator according to the vehicle's braking acceleration and the angle of the vehicle body tilting forward to achieve automatic adjustment of the braking torque.

Description

An air-cooled permanent magnet retarder that automatically adjusts braking torque

Technical field

The invention relates to the technical field of auxiliary braking for heavy-duty vehicles, and in particular to an air-cooled permanent magnet retarder that automatically adjusts braking torque.

Background technique

When vehicles pass through mountainous areas, long-distance braking may occur. Traditional braking systems may cause problems such as overheating, deterioration, wear and even failure of the braking system due to long-term braking, which may lead to traffic accidents. During long-distance transport driving, frequently stepping on the brake pedal will also increase the driver's fatigue and reduce driving safety. The GB7258 "Technical Conditions for Motor Vehicle Operation Safety" regulations promulgated by the Ministry of Transport in 1997 clearly stipulate that in order to ensure road safety, trucks and dangerous goods transport vehicles above 12 tons must be mandatory to install auxiliary braking devices.

The retarder is one of the auxiliary braking devices and is mainly used in vehicles operating in mountainous areas. Retarders currently on the market can be divided into hydraulic retarder, electromagnetic retarder and permanent magnet retarder. The work of existing retarder is realized by mechanical control, that is, a manual control device is installed in the cab, and the control function of the retarder is realized by the corresponding actuator at the retarder end. Moreover, the hydraulic retarder controls the oil flowing into the working chamber by controlling the valve to adjust the retarder output braking torque. Correspondingly, more cooling systems, pumps and valves are needed to realize the functions of the retarder. The entire mechanical and control system has a complex structure, difficult installation and poor reliability. The electromagnetic retarder requires an additional power supply system to work properly. Not only is the structure complex, but the electric excitation coil itself generates a magnetic field and also generates Joule heat, which increases the difficulty of heat dissipation of the system. Existing permanent magnet retarder usually uses pneumatic, hydraulic or motor as the execution component to adjust the retarder braking torque. It has a large number of components and complex connection structure, and its reliability is also not high.

Contents of the invention

Technical issues to be solved

In view of the above shortcomings and deficiencies of the prior art, the present invention provides an air-cooled permanent magnet retarder that automatically adjusts the braking torque, which solves the technical problems of the existing retarder having a complicated structure and being unable to automatically adjust the braking torque. .

Technical solutions

In order to achieve the above objectives, the main technical solutions adopted by the present invention include:

In a first aspect, the present invention provides an air-cooled permanent magnet retarder that automatically adjusts braking torque, including a stator. The stator includes a first conductor barrel and a conductor barrel bracket fixed to the vehicle. The first conductor The barrel is nested in the conductor barrel bracket; the transmission shaft includes an external spline shaft and a spring; the external spline shaft passes through the first conductor barrel and is between the first conductor barrel and the first conductor barrel. There is a gap that can accommodate the permanent magnet rotor, and the spring is sleeved on the external spline shaft; the permanent magnet rotor is sleeved on the external spline shaft and can be sleeved on the external spline shaft. The axial movement of the spline shaft moves into the gap and presses the spring.

The technical solution of the present invention proposes an air-cooled permanent magnet retarder that automatically adjusts the braking torque. By improving the transmission shaft of the existing vehicle, the stator and the permanent magnet rotor are sleeved on the transmission shaft. The permanent magnet rotor is It can move along the axial direction of the transmission shaft into the stator. When the vehicle generates braking acceleration or the vehicle body tilts forward, the permanent magnet rotor will automatically move relative to the transmission shaft and extend into the stator to automatically realize mechanical automatic auxiliary braking. And the permanent magnet rotor can cooperate with the spring to automatically adjust the depth into the stator according to the vehicle's braking acceleration and the angle of the vehicle body tilting forward to achieve automatic adjustment of the braking torque.

Optionally, the permanent magnet retarder further includes: a cooling fan disposed on one side of the first conductor cylinder; the cooling fan includes a cooling fan blade, a needle roller bearing and a second conductor cylinder; the roller The outer ring of the needle bearing is embedded in the conductor barrel bracket; the second conductor barrel is sleeved in the conductor barrel bracket and is used to fixedly connect the inner ring of the needle bearing to the cooling fan blade.

Set up a cooling fan to dissipate heat from the permanent magnet retarder during operation. When the permanent magnet rotor extends into the stator, eddy currents are generated between the permanent magnets and the second conductor cylinder, driving the second conductor cylinder to rotate, and then the second conductor cylinder drives the cooling fan blades to rotate to cool the permanent magnet retarder. This eliminates the need for components such as water cooling and heat dissipation, further simplifying the structure.

Optionally, the cooling fan blades are made of brass, and the length of the cooling fan blades is 50 mm. By limiting the material and length of the cooling fan blades, the heat dissipation effect of the cooling fan is guaranteed while ensuring the durability of the cooling fan.

Optionally, the outer fan blade is arranged corresponding to the outer wall of the conductor barrel bracket to dissipate heat from the outer wall of the conductor barrel bracket; the inner fan blade is corresponding to the space between the first conductor barrel and the outer spline shaft. The gap is set to dissipate heat through the gap. The outer fan blades are used to supply air to the outside of the conductor tube bracket to cool the outside of the conductor tube bracket, and the inner mountain is also used to supply air to the inside of the first conductor tube to cool down the inside of the first conductor tube. By setting up a heat dissipation system with a complex structure, the heat dissipation and cooling of the permanent magnet retarder can be achieved.

Optionally, heat dissipation fins are provided on the outside of the conductor barrel bracket in the circumferential direction. By arranging heat dissipation fins outside the conductor barrel bracket, the surface area of the conductor barrel bracket is increased, so that the conductor barrel bracket can be quickly cooled by cooling the heat dissipation fins.

Optionally, the permanent magnet rotor includes an inner spline iron yoke, a permanent magnet and a carbon fiber sheath; the inner spline iron yoke is sleeved on the outer spline shaft; the permanent magnet is embedded in the inner spline In the tooth slot of the iron yoke; the carbon fiber sheath is set on the outside of the inner spline iron yoke to fix the permanent magnet on the inner spline iron yoke. By just fitting the permanent magnet into the tooth groove of the internal spline iron yoke, the permanent magnet can be fixed easily. The carbon fiber sheath is further fixed on the outside of the internal splined iron yoke. In addition to its fixation function, the carbon fiber sheath is light in weight and high in strength. It does not affect the magnetic field and does not generate eddy currents, so it will not increase the temperature rise of the permanent magnet.

Optionally, the permanent magnets are sector-shaped rare earth permanent magnets. The permanent magnets are magnetized along the circumferential direction, and the magnetic poles of adjacent permanent magnets have opposite directions, forming a magnetization-type permanent magnet rotor.

Optionally, the transmission shaft further includes: a permanent magnet rotor block and a spring block, which are respectively fixed on the external spline shaft through screws; the permanent magnet block is arranged on the side of the permanent magnet away from the spring; The spring stopper is arranged on the side of the spring away from the permanent magnet. By arranging permanent magnet blocks and spring stops on the transmission shaft, the permanent magnets and springs are limited to limit their range of movement on the transmission shaft.

Optionally, the spring is a compression spring with its ends tightened and ground flat.

Grinding the ends tightly means eliminating the half-turn of the helix so that the end of the spring becomes an almost closed ring (similar to a round spring washer or a key ring on a key chain). The function is to increase the contact area between the spring and the end, so that the spring does not produce spring axis distortion as much as possible within the working elastic range, and keeps the reverse extension line of the force direction passing through the center line of the spring. In addition, it is the compressive rotation of the spring (top surface or low surface) provides a good sliding contact surface (one point contact prevents sliding due to concentrated pressure, causing the spring to increase in radial diameter and deform).

beneficial effects

The beneficial effects of the present invention are: the air-cooled permanent magnet retarder of the present invention that automatically adjusts the braking torque is directly improved based on the transmission shaft of the existing vehicle. It also includes a stator, a permanent magnet rotor and other parts. The stator and permanent magnet rotor are sleeved on the transmission shaft, and the stator is fixed to the vehicle body. When the vehicle generates braking acceleration or the vehicle body tilts forward, the permanent magnet rotor will automatically move relative to the transmission shaft and extend into the stator to automatically realize mechanical automatic auxiliary braking. And the permanent magnet rotor can automatically adjust the depth into the stator according to the vehicle's braking acceleration and the angle of the body's forward tilt to achieve automatic adjustment of the braking torque.

In addition, the present invention is also provided with a cooling fan for the part where the stator and the permanent magnet rotor are combined. The cooling fan dissipates heat to the permanent magnet retarder during operation, eliminating the need for components such as water cooling and heat dissipation, further simplifying the structure.

In summary, compared with the related prior art, the permanent magnet retarder of the present application eliminates the need for components such as a control system and water-cooling heat dissipation, greatly simplifies the structure, and realizes automatic control of the output torque, improving the performance of the permanent magnet retarder. The speed controller’s ease of use.

Description of the drawings

Figure 1 is an exploded schematic structural diagram of an air-cooled permanent magnet retarder that automatically adjusts braking torque provided by an embodiment of the present invention;

Figure 2 is a side view of an air-cooled permanent magnet retarder that automatically adjusts braking torque provided by an embodiment of the present invention;

Figure 3 is a cross-sectional view along line A-A of Figure 2;

Figure 4 is a schematic structural diagram of an air-cooled permanent magnet retarder that automatically adjusts braking torque provided by an embodiment of the present invention in another retarding state;

FIG. 5 is a schematic structural diagram of an air-cooled permanent magnet retarder that automatically adjusts braking torque in a retarding state according to an embodiment of the present invention.

[Explanation of reference symbols]

1: Permanent magnet rotor block;

2: Permanent magnet;

3: Carbon fiber sheath;

4: Internal spline iron yoke;

41: Internal spline iron yoke tooth groove;

5: External spline shaft;

61: First conductor barrel;

62: Second conductor barrel;

7: Conductor barrel bracket;

8: spring;

9: Needle roller bearing;

10: Cooling fan blade;

11: Spring stop.

Detailed ways

In order to better explain the present invention and facilitate understanding, the present invention will be described in detail below through specific embodiments in conjunction with the accompanying drawings. Although exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention may be understood more clearly and thoroughly, and the scope of the present invention may be fully conveyed to those skilled in the art.

Referring to Figures 1 and 2, this embodiment provides an air-cooled permanent magnet retarder that automatically adjusts braking torque, including: a stator. The stator includes a first conductor barrel 61 and a conductor barrel bracket 7 fixed to the vehicle. The first conductor barrel 61 is nested in the conductor barrel bracket 7 . The transmission shaft includes an external spline shaft 5 and a spring 8. The external spline shaft 5 passes through the first conductor barrel 61 and leaves a gap between the first conductor barrel 61 and the first conductor barrel 61 to accommodate the permanent magnet rotor. The spring 8 is sleeved on the external spline shaft 5 . The permanent magnet rotor is sleeved on the external spline shaft 5 and can move into the gap along the axial direction of the external spline shaft 5 and press against the spring.

The technical solution of the present invention proposes an air-cooled permanent magnet retarder that automatically adjusts the braking torque. By improving the transmission shaft of the existing vehicle, the stator and the permanent magnet rotor are sleeved on the transmission shaft. The permanent magnet rotor is It can move along the axial direction of the transmission shaft into the stator. When the vehicle generates braking acceleration or the vehicle body tilts forward, the permanent magnet rotor will automatically move relative to the transmission shaft and extend into the stator to automatically realize mechanical automatic auxiliary braking. And the permanent magnet rotor can cooperate with the spring 8 to automatically adjust the depth into the stator according to the braking acceleration of the vehicle and the angle of the vehicle body tilting forward to achieve automatic adjustment of the braking torque. In summary, the permanent magnet retarder provided in this embodiment changes from the conventional settings of the control system used in related technologies, realizes automatic control of the braking torque through the cooperation of the mechanical structure, simplifies the structure, and reduces the difficulty in production and manufacturing. , simple installation improves the device’s ease of use.

Among them, the length and connection mode of the external spline shaft 5 can be modified on the original transmission system. When the modified external spline shaft 5 is not parallel to the vehicle body, it is necessary to add a base with a corresponding angle at the conductor barrel bracket 7 for adjustment so that the axial direction of the base and the axial direction of the permanent magnet rotor remain concentric.

Furthermore, the material of the first conductor barrel 61 is industrial pure copper.

Optionally, as shown in FIG. 3 , the permanent magnet retarder further includes: a cooling fan, which is disposed on one side of the first conductor barrel 61 . The cooling fan includes cooling fan blades 10 , needle bearings 9 and a second conductor barrel 62 . The outer ring of the needle roller bearing 9 is embedded in the conductor barrel bracket 7 . The second conductor barrel 62 is sleeved in the conductor barrel bracket 7 and is used to firmly connect the inner ring of the needle roller bearing 9 and the cooling fan blade 10 .

Set up a cooling fan to dissipate heat from the permanent magnet retarder during operation. When the permanent magnet rotor extends into the stator, eddy currents are generated between the permanent magnet 2 and the second conductor cylinder 62, driving the second conductor cylinder 62 to rotate, and then the second conductor cylinder 62 drives the cooling fan blade 10 to rotate to slow down the permanent magnet. device to cool down. This eliminates the need for components such as water cooling and heat dissipation, further simplifying the structure.

Optionally, the cooling fan blade 10 is made of brass, and the length of the cooling fan blade 10 is 50 mm. By limiting the material and length of the cooling fan blades 10, the heat dissipation effect of the cooling fan is ensured on the premise of ensuring the durability of the cooling fan.

Among them, the fan blades are made of copper-zinc alloy brass.

Optionally, the fan blades include outer fan blades and inner fan blades. The outer fan blades are arranged corresponding to the outer side wall of the conductor tube bracket 7 to dissipate heat from the outer side wall of the conductor tube bracket 7 . The inner fan blades are arranged corresponding to the gap between the first conductor barrel 61 and the external spline shaft 5 to dissipate heat from the gap. When the permanent magnet rotor extends into the second conductor barrel 62, eddy currents are generated between the permanent magnet rotor and the second conductor barrel 62 to drive the second conductor barrel 62 to rotate the fan blades. Air is supplied to the outside of the conductor tube bracket 7 through the outer fan blades to cool the outside of the conductor tube bracket 7, and air is also supplied to the inside of the first conductor tube 61 through the inner mountain to cool down the inside of the first conductor tube 61. This realizes the heat dissipation and cooling of the permanent magnet retarder without setting up a complex heat dissipation system.

Optionally, heat dissipation fins are provided on the outside of the conductor barrel bracket 7 in the circumferential direction. By arranging heat dissipation fins on the outside of the conductor barrel bracket 7, the surface area of the conductor barrel bracket 7 is increased, so that the conductor barrel bracket 7 can be quickly cooled by cooling the heat dissipation fins.

Optionally, the conductor barrel bracket 7 is also provided with screw holes, which cooperate with the screws to fix the conductor barrel bracket 7 to the frame of the vehicle.

Among them, the conductor barrel bracket 7 is connected to the vehicle frame through four M24 screws.

Optionally, the permanent magnet rotor includes an inner spline iron yoke 4, a permanent magnet 2 and a carbon fiber sheath 3. The internal spline iron yoke 4 is sleeved on the external spline shaft 5 . The permanent magnet 2 is embedded in the internal spline iron yoke tooth groove 41 . The carbon fiber sheath 3 is placed on the outside of the inner spline iron yoke 4 to fix the permanent magnet 2 on the inner spline iron yoke 4 . By just fitting the permanent magnet 2 into the internal spline iron yoke tooth groove 41, the permanent magnet 2 can be fixed easily. The carbon fiber sheath 3 is further fixed on the outside of the inner spline iron yoke 4 . In addition to playing a fixing role, the carbon fiber sheath 3 is light in weight, high in strength, does not affect the magnetic field, does not generate eddy currents, and therefore does not increase the temperature rise of the permanent magnet 2.

Optionally, the permanent magnets 2 are sector-shaped rare earth permanent magnets 2. The permanent magnets 2 are magnetized along the circumferential direction, and the magnetic pole directions of adjacent permanent magnets 2 are opposite, forming a magnetization-type permanent magnet rotor.

Among them, the permanent magnet 2 is a neodymium iron boron rare earth permanent magnet material.

Optionally, the transmission shaft also includes: a permanent magnet rotor block 1 and a spring block 11, which are respectively fixed on the external spline shaft 5 through screws. The stopper of the permanent magnet 2 is arranged on the side of the permanent magnet 2 away from the spring 8 . The spring stop 11 is provided on the side of the spring 8 away from the permanent magnet 2 . By arranging the permanent magnet 2 stop and the spring stop 11 on the transmission shaft, the permanent magnet 2 and the spring 8 are limited to limit their range of movement on the transmission shaft.

Among them, the permanent magnet rotor block 1 and the spring block 11 are provided with screw holes, which cooperate with the screws to fix the permanent magnet 2 block and the spring block 11 on the external spline shaft 5 . The stopper is fixed through the cooperation of screws and screw holes, which is more solid and reliable. Among them, two M4 screw holes are provided on the permanent magnet rotor block 1 and the spring block 11. During installation, use hexagonal M4 screws to tighten the blocks to fix them.

Among them, the positions of the permanent magnet rotor block 1 and the spring block 11 can be adjusted according to the installation angle of the external spline shaft 5 in the vehicle and the working loading of the permanent magnet 2 retarder.

Optionally, the spring 8 is a compression spring 8 whose ends are tightened and ground flat.

Grinding the ends tightly means eliminating half a turn of the spiral, making the end of the spring 8 an almost closed ring (similar to a round spring 8 washer or a key ring on a key chain). The function is to increase the contact area between the spring 8 and the end, so that the spring 8 does not produce any distortion of the spring 8 axis within the working elastic force range, and maintains the reverse extension line of the force direction passing through the center line of the spring 8. In addition, it is the compression of the spring 8 Sexual rotation (top surface or low surface) provides a good sliding contact surface (one point contact prevents sliding due to pressure concentration, causing the radial diameter of the spring 8 to increase and deform).

The stiffness and load number of the spring 8 are calculated based on the actual friction coefficient and the mass measurement results of the permanent magnet rotor. The design principle of the spring 8 is to push the permanent magnet rotor out of the first conductor barrel 61 when the vehicle is stationary horizontally. As shown in Figure 4, the permanent magnet rotor rotates with the external spline shaft 5 without generating braking torque. When the vehicle reaches the set braking acceleration, the permanent magnet rotor slides into the first conductor barrel 61 under the action of the braking acceleration and the axial force generated by the tilt of the vehicle. The deeper it goes, eventually reaching the full-load working state in Figure 5.

Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the invention. In this way, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and equivalent technologies, the present invention should also include these modifications and variations.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above-mentioned embodiments are illustrative and should not be construed as limitations of the present invention. Those of ordinary skill in the art can make modifications to the above-mentioned embodiments within the scope of the present invention. The embodiments are subject to alterations, modifications, substitutions and variations.

Claims (8)

1. An air-cooled permanent magnet retarder that automatically adjusts braking torque, which is characterized by including: A stator, the stator includes a first conductor barrel and a conductor barrel bracket fixed to the vehicle, the first conductor barrel is nested in the conductor barrel bracket; The transmission shaft includes an external splined shaft and a spring; the external splined shaft passes through the first conductor barrel and leaves a gap between the external splined shaft and the first conductor barrel that can accommodate the permanent magnet rotor, so The spring is sleeved on the external spline shaft; A permanent magnet rotor, which is sleeved on the external spline shaft and can move into the gap along the axial direction of the external spline shaft and press against the spring; The permanent magnet retarder also includes: a cooling fan, disposed on one side of the first conductor barrel; The cooling fan includes cooling fan blades, needle bearings and a second conductor barrel; The outer ring of the needle roller bearing is embedded in the conductor barrel bracket; The second conductor barrel is sleeved in the conductor barrel bracket and used to fixedly connect the inner ring of the needle roller bearing and the cooling fan blade. 2. An air-cooled permanent magnet retarder that automatically adjusts braking torque according to claim 1, characterized in that the cooling fan blades are made of brass and the length of the cooling fan blades is 50mm. . 3. An air-cooled permanent magnet retarder that automatically adjusts braking torque according to claim 2, wherein the fan blades include outer fan blades and inner fan blades; The outer fan blades are arranged corresponding to the outer side wall of the conductor barrel bracket to dissipate heat from the outer side wall of the conductor barrel bracket; The inner fan blade is arranged corresponding to the gap between the first conductor barrel and the external spline shaft, and dissipates heat to the gap. 4. An air-cooled permanent magnet retarder that automatically adjusts braking torque according to claim 1, characterized in that, the outer side of the conductor barrel bracket is provided with heat dissipation fins along the circumferential direction. 5. An air-cooled permanent magnet retarder that automatically adjusts braking torque according to claim 1, wherein the permanent magnet rotor includes an internal splined iron yoke, a permanent magnet and a carbon fiber sheath; The internal spline iron yoke is sleeved on the external spline shaft; The permanent magnet is embedded in the internal spline iron yoke tooth groove; The carbon fiber sheath is set on the outside of the inner spline iron yoke to fix the permanent magnet on the inner spline iron yoke. 6. An air-cooled permanent magnet retarder that automatically adjusts braking torque according to claim 5, characterized in that the permanent magnet is a sector-shaped rare earth permanent magnet, and the permanent magnet is magnetized along the circumferential direction. The magnetic poles of adjacent permanent magnets have opposite directions, forming a magnetized permanent magnet rotor. 7. An air-cooled permanent magnet retarder that automatically adjusts braking torque according to claim 1, wherein the transmission shaft further includes: a permanent magnet rotor block and a spring block, which are respectively connected by screws. fixed on the external spline shaft; The permanent magnet stopper is arranged on the side of the permanent magnet away from the spring; The spring stopper is arranged on the side of the spring away from the permanent magnet. 8. An air-cooled permanent magnet retarder that automatically adjusts braking torque according to claim 1, wherein the spring is a compression spring with its ends tightened and ground flat.