CN111059179A

CN111059179A - Variable-load efficient heat dissipation type brake

Info

Publication number: CN111059179A
Application number: CN201911215853.6A
Authority: CN
Inventors: 殷玉枫; 孙煊广; 张锦; 武奎扬; 李正楠; 刘燚
Original assignee: Taiyuan University of Science and Technology
Current assignee: Taiyuan University of Science and Technology
Priority date: 2019-12-02
Filing date: 2019-12-02
Publication date: 2020-04-24

Abstract

The invention relates to the technical field of main shafts of wind turbines, in particular to a variable-load efficient heat dissipation type brake; the braking device with two groups of brake pads in the same number is adopted, and the problems of eccentric wear caused by uneven contact of the original single brake pads and various types of braking problems such as rotating speed fluctuation, poor running stability, insensitive braking force application and the like caused by stopping a braking main shaft for a long time are solved. Through improving the ventilation cooling structure (heat dissipation gusset, trapezoidal ventilation groove, heat dissipation muscle, wing section ventilation hole, circular ventilation hole, cooling bath, wavy air outlet) of brake disc and flange, solved the actual problem such as the life is shorter that too high temperature and thermal fatigue damage lead to in the brake disc operation process for a long time.

Description

Variable-load efficient heat dissipation type brake

Technical Field

The invention relates to the technical field of high-speed shaft brakes of wind turbines, in particular to a variable-load high-efficiency heat dissipation type brake.

Background

At present, the running speed of a main shaft of a wind turbine is relatively large, and a main stream braking mode is a disc brake. The existing brake has only one or two pressing forces in the braking process, and the uneven wear phenomenon occurs due to the uneven pressure distribution on the contact surface of the dual disc on the single side during braking, so that the braking force can not be quantitatively controlled, and the given accuracy of the braking force of the main shaft brake of the wind turbine is poor under different actual working conditions and different braking requirements. Secondly, because the heat generated by the friction between the brake pad and the brake disc is large, under the dual influence of alternating cycle thermal stress and thermal shock, disc structure damage, thermal shock vibration and fatigue cracks are easy to occur when the friction heat of a mating part is high, the failure of the brake disc is caused by frequent braking, and the heat dissipation and cooling of the brake seriously influence the braking performance of the wind turbine, thereby threatening the service life of the wind turbine. Therefore, it is urgently needed to provide a brake which can accurately, stably and quickly respond to brake stopping and can quickly reduce the temperature to ensure the strength and mechanical property of the brake disc.

Disclosure of Invention

The invention provides a variable-load high-efficiency heat dissipation type brake aiming at the technical problems in the working practice. Through changing the structure of the braking device, the number of the braking pieces is set to be a plurality from a single piece, and the normally-open floating caliper type mechanism is used for braking, so that the problems of various types of braking such as rough control of the speed of a main shaft of the wind turbine, uneven distribution of braking contact pressure, unstable operation, delayed braking response and the like for a long time are solved. And carry out configuration optimization to the ventilation cooling of flange and brake disc, flange department adds heat dissipation gusset and trapezoidal ventilation groove, the wing section ventilation hole that braking main and auxiliary dish department set up, the heat dissipation muscle, circular ventilation hole, the cooling bath, internal diameter department wavy air outlet, the heat that produces by the friction is through heat-conduction transmission to brake disc heat radiation structure department, the air flow trend of having changed the brake disc inside has increased the area of contact with the air simultaneously, heat exchange efficiency is improved, can also remove dust, the cleaing away of the abrasive dust of being convenient for. The structure optimization mainly solves the problems that the brake disc is damaged due to thermal fatigue caused by the fact that the temperature rises violently due to overhigh rotating speed in the braking process, and the self heat dissipation and cooling of the brake disc are greatly improved.

Aiming at the technical problems, the invention adopts the technical scheme that: six brake pads with equal size are symmetrically arranged on the two sides of the brake disc on the brake device, and the brake pads are adhered to the brake back plate and embedded into six slide rail limiting grooves with the same shape on the upper brake bracket cover and the lower brake bracket cover. The pre-pressing spring is sleeved in the guide pin and arranged between the brake plates on the two sides, and the guide pin is in interference fit with the hole on the brake back plate. The lower brake support cover is respectively provided with guide slide blocks and brake pistons, the number of the guide slide blocks and the number of the brake pistons are equal to that of the brake back plate, and the brake piston bottom plate is in contact with the guide slide blocks. The guide sliding block is arranged on the T-shaped guide rail. The upper brake bracket cover and the lower brake bracket cover are fastened through hexagon socket head cap bolts and nuts, and the back of the lower brake bracket is provided with six bolt holes with different specifications which are connected and fixed with other components.

Further optimizing the technical scheme, the flange comprises heat dissipation rib plates which are distributed on the flange surface and are connected with the shaft end flange, the heat dissipation rib plates are narrowed along the top and have draft angles of 6 degrees, and three trapezoidal ventilation grooves with different sizes, which are arranged in parallel on the rib plate surface, are parallel to the end surface of the top of the rib plate. And the key groove is connected with the main shaft, and the nine bolt holes with equal size are connected with the brake disc and are uniformly arranged in the circumferential direction.

Further optimize this technical scheme, the brake disc include brake disc main disc and brake disc auxiliary, two the same and mirror symmetry of dish specification, and fasten with hexagon head bolt and nut and gasket. The main disc of the brake disc is distributed with 15 airfoil-shaped vent holes with the same specification which are evenly arranged in the circumferential direction. The heat dissipation muscle and the wing section ventilation hole on the quotation also alternate evenly to be arranged, are the downwind direction, are provided with on the heat dissipation muscle along the circular ventilation hole of radius direction diameter by little grow, still distribute the cooling bath of two slopes on the single heat dissipation muscle. Set up to the wavy air outlet of arranging at the brake disc main disc and auxiliary disc internal diameter department alternately, the radial arch department of wavy air outlet is 9 bolt holes of equidimension, cooperates the fastening with the auxiliary disc.

Further optimize this technical scheme, the brake piston, the axial compresses tightly the direction slider, the location frock is fixed in on the fixing base of bottom plate, assembles two sealing rings in the slot department of piston department, the piston plane cooperates with the hydraulic piston cylinder internal surface and carries out axial displacement.

Compared with the prior structure, the invention has the following advantages: 1. the existing floating caliper type mechanism is skillfully introduced, so that the hydraulic oil cylinder is only arranged on one side, the space use and cost are reduced, and the problems of fault maintenance, difficult installation and the like caused by the opposite braking of the fixed caliper type braking mechanism on two sides of the brake disc are solved. 2. The arrangement of the guide slide block and the T-shaped guide rail of the braking device shortens the actual contact distance between the braking piston and the braking piece, and improves the smoothness of loading. 3. The circular ventilation hole of brake disc enables the cooling more rapid of heat dissipation muscle to can not cause too big influence to heat dissipation muscle intensity. 4. The trapezoidal ventilation grooves in the heat dissipation rib plates on the flange are favorable for changing the trend of airflow, and the cooling speed of high-temperature airflow vortexes at the brake disc and the center of the inner diameter of the flange in the operation process of the wind power main shaft is increased. 5. The ventilating and heat-dissipating structure of the brake disc and the flange is helpful for dust removal and self-cleaning of abrasive dust.

Drawings

Fig. 1 is a schematic diagram of the general structure of a variable-load high-efficiency heat dissipation brake of the present invention.

Fig. 2 is a schematic structural diagram of the brake braking device of the invention.

Fig. 3 is a schematic structural view of a brake flange of the present invention.

Fig. 4 is a schematic sectional view of the brake disk auxiliary 1/2 of the present invention.

Fig. 5 is a schematic structural diagram of a brake piston of the brake of the present invention.

Fig. 6 is a schematic view of the cross-sectional airflow trend of the brake disc auxiliary 1/4 of the present invention.

In the drawing, 1, a brake device, 2, a flange, 3, a brake disc, 4, a brake piston, 101, an upper brake support cover, 102, a slide rail limiting groove, 103, a brake back plate, 104, a brake pad, 105, a guide pin, 106, a pre-compression spring, 107, a guide slide block, 108, a T-shaped guide rail, 109, a bolt hole, 110, a lower brake support cover, 111, an inner hexagon bolt, 201, a trapezoidal ventilation groove, 202, a key groove, 203, a bolt hole, 204, a heat dissipation rib plate, 301, a brake disc main disc, 302, an airfoil ventilation hole, 303, a heat dissipation rib, 304, a cooling groove, 305, a bolt hole, 306 circular ventilation hole, 307, a wave type air outlet, 308, a brake disc auxiliary disc, 401, a bottom plate, 402, a fixed seat, 403, a positioning tool, 404, a sealing ring, 405, a piston, 406, a piston flat surface, 501, a hexagon head.

Detailed Description

In order to more clearly explain the technical solution, the using requirements and the advantages of the present invention, the specific embodiments are given with reference to the attached drawings. This description is intended to be exemplary, but not to limit the scope of the invention by the use of the full teaching of known structure dimensions and parameters.

Detailed description of the invention reference is made to fig. 1-6.

Step one, as shown in fig. 1 and fig. 2, a brake piston 4 on a brake device 1 is connected with an external hydraulic cylinder and a control system, and the obtaining of braking force is quantitatively controlled by the intake of oil liquid in the hydraulic cylinder, which is not described again herein, hydraulic pressure is transmitted to the piston 4 and is sequentially transmitted to a guide slider 107, the guide slider 107 moves under the guide of a T-shaped guide rail 108, when contacting a brake back plate 103 and a brake pad 104, the braking force is transmitted to a brake disc 3 by overcoming the elastic force of a pre-pressure spring 106, a brake disc sub-disc 308 is pushed to slide to the other side, and the brake pad 104 on the other side pushes down a brake disc main disc 301 until equal braking force exists on both sides, so as to generate a braking deceleration action. The required braking force can make a part or all of the piston 4 put into operation so as to meet the requirements under different braking conditions; step two, the braking devices 1 are divided into two groups and are respectively assembled in an up-down symmetrical mode, six brake pads 104 are respectively arranged on one side of each group, compared with the original single-piece mode, the volume is slightly increased while the number is increased, the contact area of a single brake pad 104 and the brake disc 3 is smaller, but the total contact area of the six brake pads 104 after being arranged is obviously larger than that of the single-piece type friction plate, enough space is reserved for heat dissipation of the brake disc 3 by the assembling mode of the multiple brake pads 104, although one group of braking devices 1 is added, the braking force is increased, meanwhile, the distribution and the contact area of the braking force on each brake pad 104 are more uniform, and the phenomena that the eccentric wear of the single-piece type friction plate is caused by the over-high rotating speed and the. The floating caliper type brake mechanism is skillfully introduced, the hydraulic oil cylinder is arranged on one side, the space use and cost are reduced, and the problems of difficulty in fault maintenance and installation and the like caused by opposite braking of two sides by using a fixed caliper type brake mechanism are solved. The braking force distribution on the single brake pad 104 is reduced, the strength requirement of the sealing ring 404 on the piston 4 is reduced, the service life of the sealing ring is prolonged, and the oil leakage phenomenon in the hydraulic cylinder body is avoided. The safe operation of wind power equipment and the life and property safety of workers are ensured on the whole; step three, the order of the brake pads 104 and the loading size determine the manner in which the wind turbine is stopped during each braking, and the braking mode can be adjusted according to the requirements of different braking modes. When the brake is only needed to work, maintenance or start and stop operation is carried out, no safety and serious fault problems are involved, and emergency stop is not needed, the distributed braking force is small. Therefore, we can directly call a group of brake devices 1, so that each brake pad 104 can be inserted in sequence along the clockwise direction and the anticlockwise direction, and the braking force can be increased according to the sequence of insertion of the brake pads 104; or intervening simultaneously, the braking force on each brake pad 104 will be equally distributed. For wind power equipment, when a fault occurs or the wind power equipment is longer than the rated wind speed for a long time, a control system is required to send a stop instruction, a main shaft of a fan needs to be controlled in time, and abnormal starting is avoided. Therefore, it is necessary to make both sets of brake devices 1 function, and in order to reduce the impact, the single brake pad 104 cannot be instantaneously lifted to the whole required load, a part of the brake pads 104 should be pre-braked, and then the remaining braking force is provided according to the rotation speed, so as to shorten the parking time and achieve the expected effect. The hydraulic pressure provided and the number and timing of brake pad 104 interventions can be adjusted accordingly according to the control system, and are not described herein; step four, as shown in fig. 3, 4 and 6, no matter how the braking is performed, the heat generated by the friction of the mating parts can cause the temperature of the brake disc to rise sharply, especially in the friction contact area. Because two sets of braking devices 1 are arranged, the mating parts rub against each other, and the friction process is performed twice after one rotation, so that the heat dissipation period is shorter, and the temperature rise fluctuation is more severe, and therefore, the cooling and ventilation structure optimization of the brake disc 3 and the flange 2 is necessary in the braking process. In the operation process, the air current flows in from between heat dissipation rib 303, and partly flows out from cooling trough 304 and wing section ventilation hole 302, and most flow in brake disc 3 internal diameter department, trapezoidal ventilation groove 201 exhaust air current at wavy air outlet 307 and flange 2 heat dissipation gusset 203 department, these heat radiation structure have all increased the area of contact with the air, and the cooling effect will show and improve.

It should be understood that the above embodiments are only used to explain the working mechanism of the present invention, and do not limit the scope of the present invention. Therefore, any modification made without departing from the spirit of the present invention shall be included in the scope of protection of the present invention. Further, it is intended that the appended claims cover all such variations of the invention that fall within the metes and bounds of the claims, or equivalence of such metes and bounds.

Claims

1. The utility model provides a become high-efficient heat dissipation formula stopper of load type which characterized in that: comprising a braking device (1); six brake pads (104) with equal size are symmetrically arranged on the brake device (1) relative to the two sides of the brake disc; the brake block is adhered with a brake back plate (103); and are embedded in six slide rail limiting grooves (102) with the same shape on the upper and lower brake bracket covers (101, 110); the guide pin (105) and the pre-pressing spring (106) are arranged in the middle of the brake pad (104), and the guide pin (105) is fixed with the brake back plate (103); the lower brake bracket cover (110) is respectively provided with guide slide blocks (107) and brake pistons (4) with the same number as the brake back plate (103); the brake piston (4) is arranged on the T-shaped guide rail (108); the upper brake bracket cover (101) and the lower brake bracket cover (110) are fastened through an inner hexagon bolt (111); six bolt holes (109) with different specifications are arranged on the back surface of the lower brake bracket.

2. A variable-load high-efficiency heat-dissipation brake as recited in claim 1, wherein: a flange (2); comprises heat dissipation rib plates (204) which are distributed on the root part of the flange surface connected with the shaft end flange and have a draft angle of 6 degrees along the narrowing of the top part; three trapezoidal ventilation grooves (201) with different sizes are arranged on the surface of the rib plate in parallel; there is also a keyway (202) coupled to the spindle; nine bolt holes (203) of equal size are connected with the brake disc (3).

3. A variable-load high-efficiency heat-dissipation brake as recited in claim 1, wherein: a brake disc (3); the brake disc comprises a brake disc main disc (301) and a brake disc auxiliary disc (308), wherein the two discs have the same specification and are in mirror symmetry, and are fastened by hexagon bolts, nuts and gaskets (501); 15 airfoil ventilation holes (302) with the same specification are distributed on the main brake disc (301); the radiating ribs (303) on the disk surface and the wing-shaped vent holes (302) are uniformly arranged at intervals and are all in the downwind direction; circular vent holes (306) with diameters increasing from small to large along the radius direction are arranged on the heat dissipation ribs (303); two inclined cooling grooves (304) are also distributed on the single heat dissipation rib; wave-shaped air outlets (307) which are arranged at intervals are arranged at the inner diameters of the main disc (301) and the auxiliary disc (308) of the brake disc; the protruding position of the wave-shaped air outlet is provided with 9 bolt holes (305) with the same size.

4. A variable-load high-efficiency heat-dissipation brake as recited in claim 1, wherein: comprises a brake piston (4) and an axial pressing guide slide block (107); the positioning tool (403) is fixed on a fixing seat (402) of the bottom plate (401), a sealing ring (404) is assembled on a groove at the position of the piston (405), and a piston flat surface (406) is matched with the piston cylinder.