CN111271395A

CN111271395A - Quick cooling samming brake drum suitable for truck

Info

Publication number: CN111271395A
Application number: CN202010037140.1A
Authority: CN
Inventors: 陈一; 王雷青; 江卫玉; 毛纪金; 孙利利; 徐海洋; 曹薇; 张东辉
Original assignee: Jiangsu University of Science and Technology
Current assignee: Jiangsu University of Science and Technology
Priority date: 2020-01-14
Filing date: 2020-01-14
Publication date: 2020-06-12
Anticipated expiration: 2040-01-14
Also published as: CN111271395B

Abstract

The invention discloses a rapid cooling uniform temperature brake drum suitable for a truck, wherein a liquid working medium in a heat pipe cavity is gathered at the lower part in the heat pipe cavity, and the porous capillary layer structure in the heat pipe cavity can absorb the liquid working medium when rotating along with the starting of the truck; the liquid working medium in the heat pipe cavity absorbs high temperature generated by mutual friction between the inner cylinder and the brake shoe when the truck brakes in a heating or phase change mode, air is sucked in through the heat dissipation air duct to reduce the temperature of the outer cylinder and the working medium between the outer cylinder and the inner cylinder, heat generated in the moment of braking is quickly absorbed into the liquid working medium and then uniformly released into the environment, and overlarge thermal stress caused by sudden temperature rise of the brake cylinder is avoided, so that the braking force and the safety coefficient during operation of the brake drum are improved on the premise of not reducing the service life of the brake drum; meanwhile, a water tank does not need to be arranged outside the truck for spraying and cooling the brake drum, so that the load of the truck is reduced, and the carrying capacity of the truck is improved.

Description

Quick cooling samming brake drum suitable for truck

Technical Field

The invention relates to the field of automobile brakes, in particular to a rapid cooling and temperature-equalizing brake drum suitable for a truck.

Background

The brake system is an important component of the whole automobile and is responsible for ensuring the driving safety of the automobile, and the driving speed of the automobile depends on the quality of the brake to a certain extent. At present, the mainstream brake system is generally divided into a disc brake and a drum brake, and the brake part in the drum brake comprises a brake drum, a brake shoe, a piston and the like. When the automobile is braked, the circumferential surface of the brake shoe can be violently rubbed with the inner cylinder wall of the brake drum, so that braking force is generated. However, due to the severe friction, a large amount of heat is generated and accumulated on the brake drum in a short time, so that the temperature of the brake drum is rapidly increased, and the traffic safety is threatened.

In the existing brake drum, the most commonly used mode for enhancing the brake heat dissipation is to cool by a direct spraying method. The method can indeed achieve the effects of cooling the drum brake and increasing the braking force, but also brings some problems correspondingly: manually and timely adding water into the spray water tank; the water tank occupies the volume of the truck, and the load is increased; the direct water spraying for the high-temperature brake drum can form larger thermal stress, damage the structure of the brake drum and threaten the driving safety.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to provide a rapid cooling temperature-equalizing brake drum suitable for a truck, and solves the problem that thermal stress is generated by direct spraying of a water tank spraying brake cylinder and a high-temperature brake cylinder arranged outside the truck.

The technical scheme is as follows: the invention relates to a rapid cooling temperature-equalizing brake drum suitable for trucks, which comprises an inner cylinder, an outer cylinder and a cover body, wherein connecting holes are formed in the centers of wall plates of the inner cylinder, the outer cylinder and the cover body and are used for being embedded with axles; the inner side of the inner cylinder body is embedded into a brake shoe of a truck, and the brake shoe can radially expand outwards to press the inner wall of the inner cylinder body or contract inwards to separate from the inner wall of the inner cylinder body; the inner cylinder, the outer cylinder and the cover body are fixed with a driving wheel shaft of the truck through screws; the outer cylinder body covers the inner cylinder body, the inner cylinder body and the outer cylinder body form a heat pipe cavity in a welding mode, an injection opening is reserved in the outer cylinder body, and after the brake drum is installed on a driving wheel shaft of a truck, liquid working media are injected into the injection opening and negative pressure treatment is conducted on the heat pipe cavity.

Furthermore, the outer barrel wall of the inner barrel is provided with a plurality of annular array supporting columns which are staggered in different lengths along the circumferential direction, and the supporting columns are attached to the inner barrel wall of the outer barrel.

Furthermore, the surface of the supporting column body and the outer cylinder wall of the inner cylinder body are both provided with porous capillary layers, so that the circulation of working media is facilitated, and the superheat degree of liquid during phase change is reduced, so that the heat pipe can be started and operated more quickly and better.

Furthermore, the porous capillary layer is formed by electroplating or sintering the outer ring section of the outer wall of the inner cylinder and the surface of the support column attached with metal powder, and the surface porosity of the porous capillary layer can reach 50-80 percent

Further, the metal powder is stainless steel or copper.

Furthermore, the inner wall of the outer barrel is cast with the guide strips arranged in an annular array, after the inner barrel and the outer barrel are welded, the guide strips and the support cylinders are arranged in a staggered mode and are not in contact with the inner barrel wall, and the condensation area is fully increased on the premise that the normal operation of the heat pipe is not influenced.

Furthermore, the guide strips are in a centrifugal throwing shape and assist liquid backflow.

Further, arc fins distributed radially are arranged on the outer wall of the outer cylinder body, straight fins are arranged on the outer cylinder wall of the outer cylinder body, and the straight fins and the arc fins are arranged in a staggered mode; a heat dissipation air duct is formed between the cover body and the outer cylinder wall through the arc-shaped fins and the straight fins, and the heat boundary layer can be damaged by the staggered arrangement of the air ducts, so that the heat exchange is enhanced.

Further, the arc fin includes straight section fin and the arc fin that links to each other with straight section fin is one, and arc fin is one along the circumferencial direction interval setting on the outer barrel, and straight section fin is connected at an interval to arc fin.

Furthermore, the water conservancy diversion strip and the arc fin on the interior outer wall of outer barrel are crisscross to be set up for the wall temperature of outer barrel is more even.

Has the advantages that: compared with the prior art, the invention has the advantages that: liquid working media in the heat pipe cavity are gathered at the lower part in the heat pipe cavity, and the porous capillary layer structure in the heat pipe cavity can absorb enough liquid working media when rotating along with the starting of an automobile; the liquid working medium in the heat pipe cavity absorbs high temperature generated by mutual friction between the inner cylinder and the brake shoe when the truck brakes in a heating or phase change mode, air is sucked in through the heat dissipation air duct to reduce the temperature of the outer cylinder and the working medium between the outer cylinder and the inner cylinder, heat generated in the moment of braking is quickly absorbed into the liquid working medium and then uniformly released into the environment, and overlarge thermal stress caused by sudden temperature rise of the brake cylinder is avoided, so that the braking force and the safety coefficient during operation of the brake drum are improved on the premise of not reducing the service life of the brake drum; meanwhile, a water tank does not need to be arranged outside the truck for spraying and cooling the brake drum, so that the load of the truck is reduced, and the carrying capacity of the truck is improved.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of the structure of the combination of the inner cylinder and the outer cylinder;

FIG. 3 is a sectional view showing the combination of the inner cylinder and the outer cylinder;

FIG. 4 is a schematic view of the outer barrel construction;

FIG. 5 is a schematic view of the inner cylinder and the structure of the inner cylinder;

FIG. 6 is a schematic view of the structure of the inner cylinder and the outer wall;

fig. 7 is a schematic cross-sectional view of the inner cylinder and support column and the multi-layer capillary layer.

Detailed Description

As shown in fig. 1-4, a rapid cooling temperature-equalizing brake drum suitable for a truck comprises an inner cylinder 1, an outer cylinder 2 and a cover body 3, wherein the centers of wall plates of the inner cylinder 1, the outer cylinder 2 and the cover body 3 are respectively provided with a connecting hole 4, the inner cylinder 1 is embedded into a brake shoe of the truck, the brake shoe of the truck can be radially extruded or separated from the inner wall of the inner cylinder 1, and the inner cylinder 1, the outer cylinder 2 and the cover body 3 are fixed with a driving wheel shaft of the truck through screws; the outer cylinder body 2 covers the inner cylinder body 1, a heat pipe cavity 5 is formed between the inner cylinder body and the outer cylinder body 1 in a welding mode, an injection opening 6 is reserved in the outer cylinder body 2, after the brake drum is installed on a driving wheel shaft of a truck, liquid working media are injected into the injection opening 6, and the heat pipe cavity 5 is subjected to negative pressure treatment, wherein the liquid working media are deionized water.

As shown in fig. 5-7, a plurality of support columns 7 in an annular array are arranged on the outer wall of the inner cylinder 1 along the circumferential direction, the support columns 7 are attached to the inner wall of the outer cylinder 2, porous capillary layers 11 are arranged on the surfaces of the support columns 7 and the outer wall of the inner cylinder 1, and the porous capillary layers 11 are formed by electroplating or sintering metal powder attached to the surfaces of the support columns 7 and the outer ring section of the outer wall of the inner cylinder 1, wherein the metal powder is stainless steel or copper; the surface porosity of the porous capillary layer 11 can reach 50-80%.

As shown in fig. 1-7, the inner wall of the outer cylinder 2 is cast with guide strips 8 arranged in an annular array, when the inner cylinder 1 and the outer cylinder 2 are installed and welded, the guide strips 8 are staggered with the support cylinders 7, the guide strips 8 are in a centrifugal throwing shape, and the guide strips 8 assist in liquid backflow.

Arc fins 9 distributed radially are arranged on the outer wall of the outer cylinder 2, straight fins 10 are arranged on the outer cylinder wall of the outer cylinder 2, and the straight fins 10 and the arc fins 9 are arranged in a staggered mode; a heat dissipation air duct is formed between the cover body 3 and the outer cylinder wall through arc-shaped fins 9 and straight fins 10.

The arc-shaped fins 9 comprise straight-section fins 91 and first arc-shaped fins 92 connected with the straight-section fins 91, the first arc-shaped fins 92 are arranged on the outer barrel 2 at intervals along the circumferential direction, and the first arc-shaped fins 92 are connected with the straight-section fins 91 at intervals.

The working principle is as follows: when the vehicle stops, the brake cylinder is static along with the wheels, the liquid water working medium inside is concentrated on the lower part in the heat pipe cavity 5 between the inner cylinder 1 and the outer cylinder 2, the inner cylinder 1 is not contacted with the brake shoe, and the inner wall of the inner cylinder 1 can not generate heat due to friction, so that the liquid in the heat pipe cavity 5 has no temperature rise phenomenon.

After a vehicle runs, the surface of the column 7 is supported in the heat pipe cavity 5, the porous capillary layer 11 on the outer cylinder wall of the inner cylinder 1 and the inner cylinder wall of the outer cylinder 2 is transferred to the liquid working medium concentration area in the heat pipe cavity 5, similar to the working principle of water pumping of a water-forming vehicle, when the porous capillary layer 11 absorbs enough working medium under the action of capillary force, the surface is completely wet and then transferred out of the liquid concentration area at the lower part of the heat pipe cavity 5, the circulation rotation is carried out, all the surfaces of the capillary structures are full of the liquid working medium, the inner wall of the inner cylinder 1 cannot generate heat due to friction, and therefore, the liquid in the heat pipe cavity.

When the vehicle travels and low-frequency intermittent point braking is carried out, the brake shoe and the surface of the inner cylinder wall of the brake drum inner cylinder body 1 are subjected to low-frequency intermittent friction, and a small amount of heat is generated in a short time. Heat is conducted to the inner porous capillary layer 11 through the wall surface, the liquid working medium in the porous capillary layer 11 is heated, the heat is stored in the heat pipe cavity 5, and the specific heat of the liquid water working medium is large, so that the temperature of the cavity cannot be increased violently; the outer wall of the outer cylinder body 2 is additionally provided with the arc-shaped fins 9, the outer cylinder wall is additionally provided with the long straight fins 10, an air channel is formed between the fin group in the air channel cavity and the shell and is equivalent to an impeller, on the basis of increasing the heat exchange area, the effect equivalent to a fan is achieved, and air around the center of the brake drum is driven to be quickly blown out to the outlet at the periphery of the outer cylinder body 2 of the brake drum through the arc-shaped fins 9.

When a vehicle runs on a long downhill section and is braked for a long time at a high frequency, a brake shoe and the surface of the inner cylinder wall of the inner cylinder body 1 of the brake drum generate a large amount of heat during the long-time friction at a high frequency, the heat is conducted to the inner porous capillary layer 11 through the wall surface, the liquid working medium in the porous capillary layer 11 is heated, evaporated and even boiled, the liquid working medium is changed into a gaseous working medium, the gaseous working medium is concentrated to the condensation section of the vertical section of the cavity under the action of the pressure difference in the heat pipe cavity 5, due to the action of the fin groups at the outer cylinder wall and the outer cylinder wall of the outer cylinder 2, the temperature of the whole of the inner cylinder and the inner cylinder wall of the outer cylinder 2 and the flow guide strips 8 is lower, gaseous working media are contacted with the gaseous working media, the gaseous working media are condensed into liquid working media, the heat is uniformly dispersed back to the heat source of the porous capillary layer 11 of the evaporation section under the centrifugal force generated when the cavity rotates and the auxiliary action of the flow guide strips 8, and the heat exchange cycle of evaporation and condensation is formed.

The arc-shaped fins 9 comprise straight-section fins 91 and arc-shaped fins 92 connected with the straight-section fins 91, the arc-shaped fins 92 are arranged on the outer barrel 2 at intervals along the circumferential direction, the arc-shaped fins 92 are connected with the straight-section fins 91 at intervals, and the arc-shaped fins and the straight-section fins 91 are arranged in a staggered mode to play an inlet section effect, so that the boundary layer appears when air is fully thinned and flows across the surface, and the heat exchange is enhanced.

The arrangement that the inner wall of the outer cylinder body 2 and the outer wall of the inner cylinder body 1 form a certain acute angle facilitates faster distribution of condensed liquid to the space above or below the porous capillary layer 11 during backflow.

The support columns between the inner cylinder bodies 1 are arranged in an alternating mode with different lengths so as to uniformly distribute the liquid working medium and avoid the phenomenon that the working medium is accumulated to cause that local working medium is too little to cause a high-temperature area.

Claims

1. A rapid cooling temperature-equalizing brake drum suitable for trucks comprises an inner cylinder, an outer cylinder and a cover body, wherein connecting holes are formed in the centers of wall plates of the inner cylinder, the outer cylinder and the cover body and are used for being embedded with axles; the inner side of the inner cylinder body is embedded into a brake shoe of a truck, and the brake shoe can radially expand outwards to press the inner wall of the inner cylinder body or contract inwards to separate from the inner wall of the inner cylinder body; the inner cylinder, the outer cylinder and the cover body are fixed with a driving wheel shaft of the truck through screws; the brake drum is characterized in that the outer cylinder body covers the inner cylinder body, the inner cylinder body and the outer cylinder body form a heat pipe cavity in a welding mode, an injection port is reserved in the outer cylinder body, and after the brake drum is installed on a driving wheel shaft of a truck, liquid working media are injected into the injection port and the heat pipe cavity is subjected to negative pressure treatment.

2. The rapid cooling and temperature equalizing brake drum as claimed in claim 1, wherein the outer cylinder wall of the inner cylinder has a plurality of annular array support columns of different lengths arranged in a staggered manner along the circumferential direction, and the support columns are attached to the inner cylinder wall of the outer cylinder.

3. The rapid cooling and temperature equalizing brake drum as claimed in claim 2, wherein the surface of the supporting column and the outer wall of the inner cylinder are provided with porous capillary layers, which facilitates the circulation of the working medium and reduces the superheat degree of the liquid during phase change, so that the heat pipe can be started and operated more rapidly and better.

4. The brake drum according to claim 3, wherein the porous capillary layer is formed by attaching metal powder to the surface of the supporting column and electroplating or sintering the supporting column and the inner cylinder wall, and the surface porosity of the porous capillary layer can reach 50-80%.

5. A rapid cooling temperature-equalizing brake drum suitable for trucks according to claim 4, wherein the metal powder is stainless steel or copper.

6. The rapid cooling and temperature equalizing brake drum as claimed in claim 1, wherein the inner wall of the outer cylinder is cast with guide strips arranged in an annular array, and after the inner cylinder and the outer cylinder are welded, the guide strips are staggered with the support cylinder and do not contact with the inner cylinder wall, so as to substantially increase the condensation area without affecting the normal operation of the heat pipe.

7. The rapidly-cooling temperature-equalizing brake drum suitable for trucks of claim 6, wherein the guide strips are in a centrifugal throwing shape, and the guide strips assist in liquid backflow.

8. The rapid cooling temperature-equalizing brake drum suitable for trucks as claimed in claim 1, wherein the outer wall of the outer cylinder is provided with radially distributed arc fins, the outer wall of the outer cylinder is provided with straight fins, and the straight fins and the arc fins are arranged in a staggered manner; a heat dissipation air duct is formed between the cover body and the outer cylinder wall through the arc-shaped fins and the straight fins, and the heat boundary layer can be damaged by the staggered arrangement of the air ducts, so that the heat exchange is enhanced.

9. The brake drum according to claim 8, wherein the arc-shaped fins comprise straight fins and first arc-shaped fins connected with the straight fins, the first arc-shaped fins are arranged on the outer cylinder body at intervals along the circumferential direction, and the first arc-shaped fins are connected with the straight fins at intervals.

10. The rapid cooling temperature-equalizing brake drum for trucks as claimed in claim 8, wherein the air-guiding strips and the arc-shaped fins on the inner and outer walls of the outer cylinder are staggered to make the wall temperature of the outer cylinder more uniform.