CN211117280U - Automobile drum brake with shoe wear limit alarm function - Google Patents
Automobile drum brake with shoe wear limit alarm function Download PDFInfo
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- CN211117280U CN211117280U CN201922347160.4U CN201922347160U CN211117280U CN 211117280 U CN211117280 U CN 211117280U CN 201922347160 U CN201922347160 U CN 201922347160U CN 211117280 U CN211117280 U CN 211117280U
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- roller shaft
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Abstract
The utility model discloses an automobile drum brake with shoe wear limit alarm, which comprises a cam, a cam shaft, a shoe supporting pin, a roller shaft and a dust cover; the method is characterized in that: an angle sensor is arranged aiming at the cam shaft, the angle sensor is utilized to detect the rotating angle of the cam shaft relative to the cam shaft sleeve in the braking state, an alarm circuit is triggered when the angle reaches a set angle limit value, and the alarm circuit gives out sound and/or light warning. The utility model discloses an effective detection can accurate judgement shoe's wearing and tearing state to send out the warning with the mode of sound and/or light when shoe wearing and tearing reach extreme condition, the suggestion driver in time overhauls or changes the brake shoe, avoids shoe wearing and tearing to reach the continuation after extreme condition and uses, thereby avoids causing the damage of brake part and the emergence of trouble.
Description
Technical Field
The utility model relates to an automobile drum brake, the more specifically automobile drum brake with shoe piece wearing and tearing alarming function that says so.
Background
In order to decelerate and stop the automobile during running, a service brake is mounted on each wheel, and a prior art automobile drum brake is shown in fig. 1 and 2, and comprises a brake bottom plate 19, a cam shaft 1, a shoe 2, a shoe support pin 3, a roller 7, a roller shaft 8, an adjusting arm 17, a brake air chamber 18 and a dust cover 12. When the automobile runs, the brake is frequently used to control the speed and stop the automobile according to the road condition, and the braking process of the brake is as follows: the adjusting arm 17 is pushed by the brake air chamber 18 to drive the cam shaft 1 to rotate, the cam 24 is used for opening the brake shoe, and the friction braking is realized by using the shoe riveted on the brake shoe and the brake drum. As shown in fig. 1, when the shoe is not worn, the rotation angle of the camshaft 1 in braking is a; in the long-term braking process, the shoes are continuously worn, the braking clearance is increased, and the rotating angle of the camshaft 1 is adjusted by the adjusting arm 17 along with the increase of the braking clearance, so that the braking clearance is reduced, and the braking effect is ensured; however, when the shoe wear reaches the limit position, as shown in fig. 1, when the rotation angle of the camshaft 1 in braking reaches B, the rivet head is exposed, and the shoe should be replaced in time. However, a driver cannot directly perceive the abrasion state, and the friction between the rivet head of the shoe and the brake drum occurs when the driver continues to use the brake drum, so that the brake friction force is directly reduced, and the brake drum is damaged; in severe cases, the camshaft 1 is stuck at the limit position, the brake cannot be released, and serious faults such as dragging of the brake, temperature rise, melting of bearing lubricating oil, ablation of the bearing, fire of the brake and the like can be caused.
Furthermore, the prior art brake also has problems in the following respects:
firstly, because the shoe pinhole at shoe one end is the clearance fit with shoe supporting pin 3, the outline of cam 24 and the outer periphery of gyro wheel 7 are clearance fit too between the shaft hole of gyro wheel 7 and the roller shaft 8, during braking, cam 24 rotates and promotes the shoe and expand outward, and gyro wheel 7 rotates on roller shaft 8, and the shoe pinhole at shoe 2 one end rotates on the shoe supporting pin, and these rotation parts all are in the dry grinding state, and this state can cause the excessive wearing and tearing of friction surface.
Secondly, because the brake is in a sealed state, dust generated by abrasion of the shoe and the brake drum cannot be discharged out of the brake, and dust staying below the brake drum rolls along with the rotation of the brake drum; during braking, dust is mixed between the shoe and the brake drum to reduce the friction force of the brake, the dust diffused in the brake can be attached to the shoe and the roller shaft hole to cause the phenomena of dryness and rustiness, the brake shoe is limited in activity in serious conditions, the brake cannot be released, and the phenomena of dragging and locking of the brake are caused.
SUMMERY OF THE UTILITY MODEL
The utility model discloses a for avoiding above-mentioned prior art not enough, provide an automobile drum brake that shoe abrasion limit was reported to police to send the warning when shoe abrasion reaches extreme condition in the hope, overhaul or change the brake shoe with the suggestion, prevent to continue to use the damage of the stopper part that probably causes when shoe abrasion reaches extreme condition, and prevent the emergence of trouble, guarantee driving safety.
The utility model discloses still through improving the stopper structure, avoid between horseshoe and the horseshoe supporting pin, form excessive wearing and tearing between cam and gyro wheel and roller shaft, prolong the life of stopper spare part.
The utility model discloses still through improving the stopper structure, make the dust of shoe and brake drum wearing and tearing production in time discharge, solve the dust problem of being detained.
The utility model discloses a solve technical problem and adopt following technical scheme:
the utility model discloses automobile drum brake that shoe plate wear limit was reported to police, include: the brake device comprises a brake bottom plate, a cam shaft, a shoe supporting pin, a roller shaft, an adjusting arm, a brake air chamber and a dust cover;
the utility model discloses automobile drum brake's that shoe plate wear limit was reported to police structural feature is: the method comprises the steps that an angle sensor is arranged for a cam shaft, the angle sensor is used for detecting the rotating angle of the cam shaft relative to a cam shaft sleeve in a braking state, an alarm circuit is triggered when the angle reaches a set angle limit value, and sound and/or light warning is sent out by the alarm circuit.
The utility model discloses automobile drum brake's that shoe plate wear limit was reported to police structural feature also lies in: the angle sensor adopts a contact switch: a pit is arranged at a set position of the outer circumferential surface of the camshaft, and an elastic contact is arranged on the inner side wall of the cam shaft sleeve and corresponds to the axial position of the pit; the contact switch is composed of the elastic contact and the pit and is arranged in a power supply loop of the alarm circuit in series; when the angle of the cam shaft rotating relative to the cam shaft sleeve reaches a set angle limit value, the elastic contact is embedded into the concave pit and triggers an alarm circuit.
The utility model discloses automobile drum brake's that shoe plate wear limit was reported to police structural feature also lies in: the elastic contact utilizes a nut to adjust the radial position and fix the elastic contact, and a spherical touch grinding reduction head is arranged at the front end of the elastic contact.
The utility model discloses automobile drum brake's that shoe plate wear limit was reported to police structural feature also lies in: the angle sensor adopts a non-contact switch: arranging a circle of ring grooves on the outer circumferential surface of the camshaft, arranging a magnetic boss at a set position of the ring grooves, wherein the top surface of the magnetic boss is not higher than the outer circumferential surface of the camshaft; an induction switch is arranged on the inner side wall of the cam shaft sleeve corresponding to the axial position of the magnetic boss, and the induction switch is arranged in a power supply loop of the alarm circuit in series; when the angle of the cam shaft rotating relative to the cam shaft sleeve reaches a set angle limit value, the inductive switch triggers the alarm circuit.
The utility model discloses automobile drum brake's that shoe plate wear limit was reported to police structural feature also lies in: a support pin oil storage cavity is formed in the horseshoe support pin, one end of the support pin oil storage cavity is open, and a support pin oil nozzle used for injecting lubricating oil into the support pin oil storage cavity is arranged in the open; a support pin radial oil outlet is communicated with the support pin oil storage cavity, a support pin foam column for controlling the oil outlet amount is filled in the support pin radial oil outlet, and lubricating oil stored in the support pin oil storage cavity permeates into a contact surface between the horseshoe pin hole and the horseshoe support pin through the radial oil outlet; and a horseshoe pin hole sealing ring is respectively arranged between the horseshoe pin hole and the horseshoe supporting pin and positioned at the two ends of the horseshoe pin hole.
The utility model discloses automobile drum brake's that shoe plate wear limit was reported to police structural feature also lies in: a roller shaft oil storage cavity is arranged in the roller shaft, one end of the roller shaft oil storage cavity is open, and a roller shaft oil nozzle used for injecting lubricating oil into the roller shaft oil storage cavity is arranged in the open; a roller shaft radial oil outlet is communicated with the roller shaft oil storage cavity, a roller shaft foam column for controlling the oil output is filled in the roller shaft radial oil outlet, and lubricating oil stored in the roller shaft oil storage cavity permeates into the contact surface of the roller and the roller shaft through the radial oil outlet; and roller sealing rings are respectively arranged between the roller and the roller shaft and at two ends of the roller.
The utility model discloses automobile drum brake's that shoe plate wear limit was reported to police structural feature also lies in: the roller is provided with a radial through hole which is communicated with a radial oil outlet of the roller shaft, and lubricating oil stored in an oil storage cavity of the roller shaft permeates into a contact surface between the roller and the cam through the radial through hole.
The utility model discloses automobile drum brake's that shoe plate wear limit was reported to police structural feature also lies in: and an eversion ventilation opening is arranged on the end face of the dust cover, and the opening of the ventilation opening is positioned on the windward side of the vehicle, so that the vehicle in running forms airflow towards the interior of the brake by utilizing the ventilation opening.
Compared with the prior art, the utility model discloses beneficial effect embodies:
1. the utility model can accurately judge the abrasion state of the shoe through effective detection, and send out warning in a sound and/or light mode when the abrasion of the shoe reaches the limit state, so as to prompt a driver to overhaul or replace the brake shoe in time, and avoid the continuous use after the abrasion of the shoe reaches the limit state, thereby avoiding the damage and the fault of the brake part;
2. the utility model avoids the excessive wear of the shoe, shoe supporting pin, cam, roller shaft and other parts, prolongs the service life of brake parts and reduces the maintenance cost through the oil storage lubrication;
3. the oil storage lubrication of the utility model can greatly improve the corrosion and clamping stagnation phenomena of the related parts;
4. the utility model discloses a set up the ventilation hole on the shield, in the automobile driving, utilize the ventilation hole to form the air current of forcing towards the stopper in, make the dust in the stopper discharge the stopper under the effect of air current on the one hand, on the other hand, the air current makes the stopper inner part obtain the forced air cooling, is of value to greatly reducing the high temperature that produces in the stopper braking process, prevents to decline the reliability that improves the stopper because of the braking heat that the high temperature leads to.
5. The utility model discloses can use on various air brake vehicles, use extensively.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;
reference numbers in the figures: the cam shaft, the cam shaft sleeve 1a, the shoe 2, the shoe supporting pin 3, the supporting pin oil storage cavity 4, the supporting pin foam column 5, the supporting pin oil nozzle 6, the roller 7, the roller radial through hole 7a, the roller shaft 8, the roller shaft oil storage cavity 9, the roller shaft foam column 10, the roller shaft oil nozzle 11, the dust cover 12, the vent hole 13, the elastic contact 14, the pit 15, the shoe pin hole sealing ring 16a, the roller sealing ring 16b, the adjusting arm 17, the braking air chamber 18, the braking bottom plate 19, the alarm lamp 20, the power supply 21, the nut 22, the spherical contact deceleration head 23 and the cam 24.
Detailed Description
Referring to fig. 1 and 2, an automotive drum brake includes: brake bottom plate 19, cam 24, camshaft 1, shoe 2, shoe support pin 3, roller 7, roller shaft 8, adjusting arm 17, brake chamber 18 and dust cover 12.
As shown in fig. 1 and fig. 2, the structural form of the drum brake for an automobile with a shoe wear limit alarm in the embodiment is as follows:
an angle sensor is arranged aiming at the camshaft 1, the angle sensor is utilized to detect the rotating angle of the camshaft 1 relative to the camshaft sleeve 1a in the braking state, an alarm circuit is triggered when the angle reaches a set angle limit value, and the alarm circuit gives out sound and/or light warning.
In specific implementation, the angle sensor may adopt a contact switch: a pit 15 is arranged at a set position on the outer circumferential surface of the camshaft 1, and an elastic contact 14 is arranged on the inner side wall of the camshaft sleeve 1a and corresponds to the axial position of the pit 15; a contact switch composed of an elastic contact 14 and a pit 15, the contact switch is arranged in series in a power supply loop of an alarm circuit, the alarm circuit with a simple structure is illustrated in fig. 2 and comprises a power supply 21 and an alarm lamp 20; when the angle of the camshaft 1 rotating relative to the camshaft sleeve 1a reaches a set angle limit value, the elastic contact 14 is embedded into the concave pit 15 and triggers an alarm circuit, at the moment, power is supplied by the power supply 21, and the alarm lamp 20 gives out an alarm.
The elastic contact 14 shown in fig. 2 is fixed by adjusting the radial position with a nut 22, and a spherical contact head 23 is arranged at the front end of the elastic contact 14 to reduce the abrasion and prolong the service life of the device.
In a specific embodiment, the angle sensor may also be a non-contact switch: a circle of ring grooves are arranged on the outer circumferential surface of a camshaft 1, a magnetic boss is arranged at a set position of each ring groove, and the top surface of each magnetic boss is not higher than the outer circumferential surface of the camshaft 1; an induction switch is arranged on the inner side wall of the cam shaft sleeve 1a corresponding to the axial position of the magnetic boss, and the induction switch is arranged in a power supply loop of the alarm circuit in series; when the angle of the camshaft 1 rotating relative to the camshaft sleeve 1a reaches a set angle limit value, the inductive switch triggers an alarm circuit.
The utility model discloses in time indicate the driver to overhaul when shoe plate wearing and tearing reach extreme condition, effectively avoided shoe plate wearing and tearing to reach the continuation after extreme condition to use, avoid causing the damage of stopper part and the emergence of trouble.
As shown in fig. 2, in order to reduce wear between the shoe pin hole and the shoe support pin 3, in the present embodiment, a support pin oil storage chamber 4 is provided in the shoe support pin 3, one end of the support pin oil storage chamber 4 is open, and a support pin oil nozzle 6 for injecting lubricating oil into the support pin oil storage chamber is provided in the open; a support pin radial oil outlet is communicated with the support pin oil storage cavity 7, a support pin foam column 5 for controlling the oil outlet amount is filled in the support pin radial oil outlet, and lubricating oil stored in the support pin oil storage cavity permeates into the contact surface between the horseshoe pin hole and the horseshoe support pin 3 through the radial oil outlet; and a shoe pin hole sealing ring 16a is arranged between the shoe pin hole and the shoe supporting pin 3 and positioned at two ends of the shoe pin hole respectively to avoid oil leakage.
As shown in fig. 2, in order to reduce the wear between the roller 7 and the roller shaft 8, in the present embodiment, a roller shaft oil storage chamber 9 is provided in the roller shaft 8, one end of the roller shaft oil storage chamber 9 is open, and a roller shaft oil nozzle 11 for injecting lubricating oil into the roller shaft oil storage chamber is provided in the open; a roller shaft radial oil outlet is communicated with the roller shaft oil storage cavity, a roller shaft foam column 10 for controlling the oil outlet amount is filled in the roller shaft radial oil outlet, and lubricating oil stored in the roller shaft oil storage cavity permeates into the contact surface of the roller 7 and the roller shaft 8 through the radial oil outlet; roller seal rings 16b are respectively disposed between the roller 7 and the roller shaft 8 and at both ends of the roller 7 to prevent oil leakage.
As shown in fig. 2, in order to reduce the wear between the roller 7 and the rim of the cam 24, in the present embodiment, a roller radial through hole 7a is provided in the roller 7, the roller radial through hole 7a communicates with a roller shaft radial oil outlet, and the lubricating oil stored in the roller shaft oil reservoir 9 permeates into the contact surface between the roller 7 and the cam 24 through the roller radial through hole 7 a.
The utility model avoids the excessive wear of the shoe, shoe supporting pin, cam, roller shaft and other parts, prolongs the service life of brake parts and reduces the maintenance cost through the oil storage lubrication; meanwhile, the oil storage lubrication greatly improves the phenomena of corrosion and clamping stagnation of related parts.
As shown in fig. 2, in the present embodiment, an eversion vent 13 is provided on the end face of the dust cover 12, and the opening of the vent 13 is on the windward side of the vehicle, so that the vehicle in running forms airflow towards the inside of the brake by using the vent; when the automobile moves, the ventilation opening 13 forms forced airflow towards the brake, dust in the brake is discharged out of the brake, and the airflow is used for cooling the inner parts of the brake, so that the working temperature of the brake is reduced, brake heat recession caused by high temperature is prevented, and the reliability of the brake is effectively improved.
Claims (8)
1. An automotive drum brake with shoe wear limit warning, comprising: the brake device comprises a brake bottom plate (19), a cam (24), a cam shaft (1), a shoe (2), a shoe supporting pin (3), a roller (7), a roller shaft (8), an adjusting arm (17), a brake air chamber (18) and a dust cover (12); the method is characterized in that: an angle sensor is arranged aiming at the camshaft (1), the angle sensor is utilized to detect the rotating angle of the camshaft (1) relative to the cam shaft sleeve (1a) in a braking state, an alarm circuit is triggered when the angle reaches a set angle limit value, and sound and/or light warning is sent out by the alarm circuit.
2. The shoe wear limit alarm automotive drum brake of claim 1, further characterized by: the angle sensor adopts a contact switch: a concave pit (15) is arranged at a set position of the outer circumferential surface of the camshaft (1), and an elastic contact (14) is arranged on the inner side wall of the cam shaft sleeve (1a) and corresponds to the axial position of the concave pit (15); the contact switch is composed of the elastic contact (14) and the pit (15), and is arranged in a power supply loop of the alarm circuit in series; when the angle of the camshaft (1) rotating relative to the cam shaft sleeve (1a) reaches a set angle limit value, the elastic contact (14) is embedded into the concave pit (15) and triggers an alarm circuit.
3. The shoe wear limit alarm automotive drum brake of claim 2, further characterized by: the elastic contact (14) is adjusted in radial position by a nut (22) and fixed, and a spherical touch abrasive reduction head (23) is arranged at the front end of the elastic contact (14).
4. The shoe wear limit alarm automotive drum brake of claim 1, further characterized by: the angle sensor adopts a non-contact switch: a circle of ring grooves are formed in the outer circumferential surface of the camshaft (1), a magnetic boss is arranged at a set position of each ring groove, and the top surface of each magnetic boss is not higher than the outer circumferential surface of the camshaft (1); an induction switch is arranged on the inner side wall of the cam shaft sleeve (1a) corresponding to the axial position of the magnetic boss, and the induction switch is arranged in a power supply loop of the alarm circuit in series; when the angle rotated by the camshaft (1) relative to the cam shaft sleeve (1a) reaches a set angle limit value, the inductive switch triggers an alarm circuit.
5. The shoe wear limit alarm automotive drum brake of claim 1, 2 or 4, wherein: a support pin oil storage cavity (4) is formed in the shoe support pin (3), one end of the support pin oil storage cavity (4) is open, and a support pin oil nozzle (6) used for injecting lubricating oil into the support pin oil storage cavity is arranged in the open; a support pin radial oil outlet is communicated with the support pin oil storage cavity (4), a support pin foam column (5) for controlling oil outlet amount is filled in the support pin radial oil outlet, and lubricating oil stored in the support pin oil storage cavity permeates into a contact surface between a horseshoe pin hole and the horseshoe support pin (3) through the radial oil outlet; and a shoe pin hole sealing ring (16a) is arranged between the shoe pin hole and the shoe supporting pin (3) and positioned at two ends of the shoe pin hole respectively.
6. The shoe wear limit alarm automotive drum brake of claim 1, 2 or 4, wherein: a roller shaft oil storage cavity (9) is arranged in the roller shaft (8), one end of the roller shaft oil storage cavity (9) is open, and a roller shaft oil nozzle (11) used for injecting lubricating oil into the roller shaft oil storage cavity is arranged in the open; a roller shaft radial oil outlet is communicated with the roller shaft oil storage cavity, a roller shaft foam column (10) for controlling the oil output is filled in the roller shaft radial oil outlet, and lubricating oil stored in the roller shaft oil storage cavity (9) permeates into the contact surface of the roller (7) and the roller shaft (8) through the radial oil outlet; and roller sealing rings (16b) are respectively arranged between the roller (7) and the roller shaft (8) and positioned at two ends of the roller (7).
7. The shoe wear limit alarm automotive drum brake of claim 1, further characterized by: the roller (7) is provided with a roller radial through hole (7a), the roller radial through hole (7a) is communicated with a roller shaft radial oil outlet, and lubricating oil stored in the roller shaft oil storage cavity (9) permeates into a contact surface between the roller (7) and the cam (24) through the roller radial through hole (7 a).
8. The shoe wear limit alarm automotive drum brake of claim 1, further characterized by: an eversion ventilation opening (13) is arranged on the end face of the dust cover (12), the opening of the ventilation opening (13) is positioned on the windward side of the vehicle, and the vehicle in running forms airflow towards the interior of the brake by using the ventilation opening.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922347160.4U CN211117280U (en) | 2019-12-24 | 2019-12-24 | Automobile drum brake with shoe wear limit alarm function |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922347160.4U CN211117280U (en) | 2019-12-24 | 2019-12-24 | Automobile drum brake with shoe wear limit alarm function |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN211117280U true CN211117280U (en) | 2020-07-28 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201922347160.4U Active CN211117280U (en) | 2019-12-24 | 2019-12-24 | Automobile drum brake with shoe wear limit alarm function |
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| Country | Link |
|---|---|
| CN (1) | CN211117280U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114962507A (en) * | 2022-05-31 | 2022-08-30 | 江苏理工学院 | Automobile drum brake |
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2019
- 2019-12-24 CN CN201922347160.4U patent/CN211117280U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114962507A (en) * | 2022-05-31 | 2022-08-30 | 江苏理工学院 | Automobile drum brake |
| CN114962507B (en) * | 2022-05-31 | 2023-09-22 | 江苏理工学院 | Automobile drum brake |
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