Adjustable brake assembly

Abstract

The invention discloses an adjustable brake assembly which comprises an axle rod and an axle housing provided with a brake shoe, and further comprises a rotatably arranged brake drum, notches are formed in the circumference of the inner wall of the brake drum, and arc blocks are movably arranged in the notches. According to the adjustable brake assembly, the middle shoe is actively attached to the arc block in the rotating state by slightly stepping the pedal, sliding friction is generated for speed reduction of the brake drum, when speed reduction or braking is needed again after speed reduction, the pedal is forcibly stepped to enable the middle shoe to abut against and push the arc block to retract into the notch, and the brake drum is driven to rotate. The middle shoe is further in contact with the inner wall of the brake drum when making contact with the arc blocks, the side shoes are completely in contact with the inner wall of the brake drum, the whole shoe module works and is used for braking of the brake drum, segmented use of the braking function is achieved, speed reduction and braking after speed reduction can be conducted in the high-speed state, abrasion to the shoe module is effectively reduced, and the service life of the brake drum is prolonged. The service life of the brake shoe is prolonged, and the use cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of brake devices, and in particular to an adjustable brake assembly. Background Art

[0002] Drum brakes and disc brakes are two common braking methods on the market. Due to the low cost of drum brakes, they are commonly found on two-wheeled electric vehicles and three-wheeled electric vehicles. Some special drum brakes are also used on large trucks. The braking method of drum brakes mainly uses the friction pad on the brake shoe to squeeze the inner wall of the brake drum.

[0003] According to the publication (announcement) number: CN111976666A, publication (announcement) date: 2020-11-24, a friction brake device is disclosed.

[0004] In the prior art including the above-mentioned patent, the drum brake used on the tricycle often adopts the pulling method of connecting the pedal to the steel wire rope for braking. However, due to the use of a knob at the connection position between the steel wire rope and the brake drum, it is very easy to be bumped and loosened due to uneven road surface, which in turn causes a "feeling of powerlessness" in the process of lightly stepping on the pedal, and it is impossible to directly react to deceleration. Therefore, it is necessary to step on the pedal hard to achieve deceleration. However, the friction pad on the brake shoe has been excessively worn during the force application process. After the knob is readjusted to be loose, the friction pad on the brake shoe can no longer achieve the original light-stepping deceleration effect, and this state will continuously increase the consumption of the friction pad, shorten the brake shoe replacement cycle, and increase the cost of use. If the friction pad on the brake shoe cannot be replaced in time, it will affect the braking deceleration and braking effect, and even cause traffic accidents. Summary of the invention

[0005] The object of the present invention is to provide an adjustable brake assembly, aiming to solve the above-mentioned problems.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] An adjustable brake assembly includes an axle rod and an axle housing provided with a brake shoe, and also includes a rotatably arranged brake drum, wherein the inner wall of the brake drum is circumferentially arranged with notches, and an arc block is movably arranged in the notch;

[0008] An eccentric block is rotatably arranged in the axle housing to resist the opening / closing of the brake shoes;

[0009] The brake shoe is provided with a shoe module, and the shoe module is divided into a middle shoe and a side shoe according to the function. The shoe module is driven by an eccentric block and has the following two stations:

[0010] In the first work station, the arc block is slidably matched with the middle shoe;

[0011] At the second workstation, the middle shoe piece pushes the arc block to retract the notch, and the middle shoe piece and the side shoe piece are slidably matched with the inner wall of the brake drum.

[0012] Preferably, a capsule is fixedly installed in the notch, the arc block is fixedly connected to the capsule, and a protective sheet extending out of the brake drum port is fixedly installed on the capsule;

[0013] The arc block in the retracted state squeezes the capsule to deform, and causes the protective sheet to slide against the inner wall of the shaft housing.

[0014] Preferably, a brake shaft for assembling a cable pull head is rotatably arranged on the shaft housing, and an insert shaft movable in the brake shaft is arranged on the eccentric block;

[0015] An oblique screw groove is provided on the insertion shaft, a guide rod is movably provided in the shaft housing, and the end of the guide rod abuts and slides in the oblique screw groove, so as to make the rotation angle of the eccentric block adjustable.

[0016] Preferably, a positioning rod is provided on the insertion shaft, and positioning holes arranged at equal distances are opened on the brake shaft, and the eccentric block in a rotating state enables the positioning rod to be inserted into the positioning holes in sequence.

[0017] Preferably, a shell ring located outside the brake drum is slidably arranged on the end surface of the shaft shell, and a protrusion for abutting against the matching guide rod is arranged on the shell ring.

[0018] Preferably, the movable sleeve on the brake drum is provided with a driving ring, and the driving ring is divided into a screw ring and a push-pull ring according to its function;

[0019] The screw ring is threadedly connected to the brake drum and enables the push-pull ring to move horizontally against the push-shell ring.

[0020] Preferably, the inner wall of the push-pull ring is slidably provided with a plurality of arc strips, and the arc block is fixedly provided with symmetrically arranged contact blocks;

[0021] A trigger rod is fixedly mounted on the arc bar and is in contact with the contacted block, and is used to make the arc block extend out of / retract into the notch.

[0022] Preferably, a pressure rod is hingedly provided on the shaft housing, and a shielding piece located outside the wire pulling head is provided on the pressure rod.

[0023] Preferably, the guide rod is provided with elastic teeth arranged in an array, and the pressure rod is provided with a limit rod coupled with the elastic teeth;

[0024] The guide rod under reciprocating motion causes the elastic teeth to push the limit rod to deflect, and shortens the distance between the pressure rod and the wire pulling head.

[0025] Preferably, the movable protective sheet is in abutment with the guide rod.

[0026] In the above technical scheme, an adjustable brake assembly provided by the present invention has the following beneficial effects: when the tricycle needs to slow down at high speed, the pedal is lightly stepped on to make the eccentric block open the two brake shoes, so that the middle shoe actively approaches the arc block in the rotating state and contacts it, thereby generating sliding friction to be used as the brake drum to slow down; and when it is necessary to slow down or stop again after deceleration, the pedal is pressed hard to make the middle shoe push the arc block back into the notch. At this time, the inner arc surface of the arc block is flush with the inner wall of the brake drum, so that the middle shoe also contacts the inner wall of the brake drum during the process of contacting the arc block, and the side shoe completely contacts the inner wall of the brake drum, so that the entire shoe module is in a working state, and the generated sliding friction is used for braking the brake drum, thereby parking the wheel, thereby realizing the segmented use of the braking function, and can be used for deceleration at high speed and braking after deceleration, effectively reducing the wear on the shoe module, increasing the service life of the brake shoe, and reducing the cost of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0028] Figure 1 A schematic diagram of a brake and tire assembly plane provided by an embodiment of the present invention;

[0029] Figure 2 A schematic diagram of an exploded right side view of an axle, an axle housing, a drive ring, a housing ring and a brake drum provided in an embodiment of the present invention;

[0030] Figure 3 A schematic diagram of an exploded left side view of an axle, an axle housing, a drive ring, a housing ring and a brake drum provided in an embodiment of the present invention;

[0031] Figure 4 A schematic side cross-sectional view of an axle, an axle housing, a drive ring, a housing ring and a brake drum provided in an embodiment of the present invention;

[0032] Figure 5 for Figure 4 A magnified schematic diagram of point A;

[0033] Figure 6 A schematic diagram of a left side view of a side section view of a shaft housing, a drive ring, a housing ring and a brake drum structure of a brake provided by an embodiment of the present invention;

[0034] Figure 7 A schematic diagram of the assembly of the eccentric block, the brake shaft, the guide rod and the pressure rod provided in an embodiment of the present invention;

[0035] Figure 8for Figure 7 An enlarged schematic diagram of point B;

[0036] Fig. 9 A schematic diagram of a positioning rod and a plurality of positioning holes to be matched with each other provided in an embodiment of the present invention;

[0037] Fig.10 A schematic diagram of the sliding fit between the guide rod and the oblique screw groove section provided in an embodiment of the present invention;

[0038] Fig.11 A schematic diagram of the coordination of arc bars and arc blocks provided in an embodiment of the present invention.

[0039] Description of reference numerals:

[0040] 1. Axle rod; 2. Axle housing; 21. Brake shoe; 22. Shoe module; 221. Middle shoe; 222. Side shoe; 3. Brake drum; 31. Notch; 4. Eccentric block; 41. Block shaft; 42. Insert shaft; 43. Brake shaft; 44. Pull wire head; 5. Drive ring; 51. Screw ring; 52. Push-pull ring; 53. Arc bar; 531. Trigger rod; 6. Arc block; 61. Contact block; 62. Capsule; 63. Protective sheet; 631. Protective groove; 7. Shell ring; 71. Protrusion; 8. Guide rod; 81. Elastic tooth; 82. Oblique screw groove; 83. Positioning rod; 831. Positioning hole; 9. Pressure rod; 91. Covering piece; 92. Limit rod. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0042] like Figure 1-11 As shown, an adjustable brake assembly includes an axle rod 1 and an axle housing 2 provided with a brake shoe 21, and also includes a rotatably arranged brake drum 3, the inner wall of the brake drum 3 is circumferentially arranged with notches 31, and an arc block 6 is movably arranged in the notch 31;

[0043] An eccentric block 4 is rotatably disposed in the axle housing 2 to resist the brake shoe 21 from opening or closing;

[0044] The brake shoe 21 is provided with a shoe module 22, and the shoe module 22 is divided into a middle shoe 221 and a side shoe 222 according to the function. The shoe module 22 is driven by the eccentric block 4 and has the following two stations:

[0045] In the first station, the arc block 6 and the middle shoe 221 are slidably matched;

[0046] In the second working station, the middle shoe piece 221 pushes the arc block 6 to retract the notch 31, and the middle shoe piece 221 and the side shoe piece 222 are slidably matched with the inner wall of the brake drum 3.

[0047] Specifically, the brake drum 3 is fixedly mounted on the wheel of the tricycle, and the wheel is driven to rotate by the axle rod 1, and the axle housing 2 is fixedly mounted on a bracket that provides rotation for the axle rod 1, and the brake shoe 21 is hinged in the axle housing 2, which are all existing technologies and will not be described here.

[0048] Furthermore, the two inner corners of the arc block 6 are rounded, so that when the arc block 6 rotates with the brake drum 3 and contacts the middle shoe 221, a jamming problem can be avoided.

[0049] Furthermore, the shoe module 22 is a friction pad used for friction braking in the prior art and is divided into three sections, wherein the section in the middle is a middle shoe 221 and the sections on both sides of the middle shoe 221 are side shoes 222 so that the shoe module 22 can be used separately.

[0050] Furthermore, when the axle housing 2 and the brake drum 3 are assembled, the arc block 6 and the middle shoe 221 are on the same vertical plane, and the arc block 6 does not contact the side shoe 222, and the arc block 6 extends out of the notch 31 in the default state, so that the middle shoe 221 can slide and rub with the arc block 6 first.

[0051] Furthermore, the distance between the hinged positions of the two brake shoes 21 and the distance between the two brake shoes 21 after being pushed by the eccentric block 4 and fully opened are both smaller than the length of the arc block 6, and the circumferentially arranged arc blocks 6 can also reduce the heat generated by friction.

[0052] When the tricycle needs to slow down at high speed, the pedal is lightly stepped on to make the eccentric block 4 open the two brake shoes 21, so that the middle shoe piece 221 actively approaches the arc block 6 in the rotating state and contacts it, thereby generating sliding friction to be used for deceleration of the brake drum 3. When it is necessary to slow down or stop again after deceleration, the pedal is pressed hard to make the middle shoe piece 221 push the arc block 6 to retract into the notch 31. At this time, the inner arc surface of the arc block 6 is flush with the inner wall of the brake drum 3, so that the middle shoe piece 221 also contacts the inner wall of the brake drum 3 during the process of contacting the arc block 6, and the side shoe piece 222 completely contacts the inner wall of the brake drum 3, so that the entire shoe piece module 22 is in a working state, and the generated sliding friction is used for braking the brake drum 3, thereby stopping the wheel, thereby realizing the segmented use of the braking function, and can be used for deceleration at high speed and braking after deceleration, effectively reducing the wear on the shoe piece module 22, increasing the service life of the brake shoe 21, and reducing the cost of use.

[0053] As an embodiment further provided by the present invention, a capsule 62 is fixedly installed in the notch 31, the arc block 6 is fixedly connected to the capsule 62, and a protective sheet 63 extending out of the port of the brake drum 3 is fixedly installed on the capsule 62;

[0054] The arc block 6 in the retracted state squeezes the capsule 62 to deform, and causes the protection sheet 63 to slide against the inner wall of the shaft housing 2 .

[0055] Specifically, the notch 31 presents a cross-arranged channel, and the channels are respectively used to accommodate the capsule 62 and the sliding arc block 6, and the channel accommodating the capsule 62 extends to the edge of the port of the brake drum 3, which is used to make part of the capsule 62 outside the port of the brake drum 3 so that the protective sheet 63 can be in sliding contact with the axle housing 2.

[0056] Furthermore, the bladder body 62 is specifically a corrosion-resistant rubber bladder, and the existing material is not described here. An annular protective groove 631 is opened on the shaft housing 2.

[0057] After the brake drum 3 and the shaft housing 2 are assembled, the protective sheet 63 is pressed into the protective groove 631 by the capsule 62. When the brake drum 3 rotates, the protective sheet 63 forms a shielding protection inside the brake to reduce the entry of external dirt into the brake. When the arc block 6 retracts into the notch 31, the side of the capsule 62 is squeezed, causing the capsule 62 at the protective sheet 63 to deform and bulge again. On the one hand, the contact stability between the protective sheet 63 and the protective groove 631 is increased, and on the other hand, the contact surface between the capsule 62 and the protective groove 631 is improved, further enhancing the shielding and intercepting effect of dirt. At the same time, the centrifugal force generated by the high-speed rotating brake drum 3 will cause the arc block 6 to actively squeeze the capsule 62, thereby increasing the distance between the arc block 6 and the inactive shoe module 22, so that the enlarged gap can pass through and leak dirt, thereby avoiding the accumulation and blockage of dirt and interference with the brake.

[0058] As another embodiment further provided by the present invention, a brake shaft 43 for assembling a cable pull head 44 is rotatably provided on the shaft housing 2, and an insert shaft 42 movable in the brake shaft 43 is provided on the eccentric block 4;

[0059] An oblique screw groove 82 is provided on the insertion shaft 42 , and a guide rod 8 is movably provided in the shaft housing 2 , and the end of the guide rod 8 abuts and slides in the oblique screw groove 82 , so as to make the rotation angle of the eccentric block 4 adjustable.

[0060] Specifically, the wire pull head 44 is provided with a knob to connect and tighten the wire rope, and the brake shaft 43 is provided with a torsion spring connected to the outer end surface of the shaft housing 2, which are all prior arts and will not be described in detail here.

[0061] Furthermore, a block shaft 41 having the same diameter as the brake shaft 43 is fixedly mounted on the eccentric block 4, and the plug shaft 42 is fixedly mounted on the block shaft 41, and a hole for the plug shaft 42 to move is opened on the brake shaft 43, so that the eccentric block 4 and the brake shaft 43 can be used in conjunction with each other.

[0062] Furthermore, a tension spring is fixedly installed at the end of the insertion shaft 42 , and a disc is fixedly installed at the end of the tension spring, and the disc rotates in the hole of the brake shaft 43 .

[0063] Furthermore, the eccentric block 4 and the brake shoe 21 are hinged at the upper and lower positions, while the guide rod 8 remains vertically movable, and the oblique screw groove 82 is spirally arranged, and the groove is from shallow to deep to slide against the end of the guide rod 8 (such as Fig.10 shown).

[0064] By inserting the vertically movable guide rod 8 into the oblique screw groove 82, and making the end of the guide rod 8 slide from the shallow position to the deep position of the oblique screw groove 82, the plug shaft 42 is prompted to move axially, and along with the spiral shape of the oblique screw groove 82, the plug shaft 42 is rotated, thereby rotating the eccentric block 4, and the purpose of this rotation is to change the pre-angle of the eccentric block 4. When the existing rounded rectangular eccentric block 4 is rotated 90°, the brake shoe 21 will open at the maximum angle, but the rotation angle of the eccentric block 4 will not exceed 90°, because after exceeding 90°, the rounded rectangular eccentric block 4 will cause the brake shoe 21 to be close together. Therefore, before reaching 90° is the maximum working range of the brake shoe 21, but when the shoe module 22 is worn, the fixed stroke pedal cannot fully The friction between the shoe module 22 and the brake drum 3 causes a feeling of powerlessness during braking. However, after the preset angle of the eccentric block 4 is changed, the eccentric block 4 pushes the brake shoe 21 to open, thereby compensating for the wear of the shoe module 22 (for example, the original deflection angle of the eccentric block 4 is 0-70°, and the unworn shoe module 22 can contact the inner wall of the brake drum 3 to achieve braking, but after a lot of wear, it cannot contact the inner wall of the brake drum 3 when it is deflected to 70°, thus causing a feeling of powerlessness during braking; but when the deflection angle of the eccentric block 4 is changed to 10°-80°, the shoe module 22 after a lot of wear can also contact the inner wall of the brake drum 3 to achieve braking), which is used to enhance the utilization efficiency of the shoe module 22, reduce the replacement cycle of the brake shoe 21, and ensure the braking effect.

[0065] As another embodiment further provided by the present invention, a positioning rod 83 is provided on the insertion shaft 42, and positioning holes 831 arranged equidistantly are opened on the brake shaft 43, and the eccentric block 4 in a rotating state enables the positioning rod 83 to be inserted into the positioning holes 831 in sequence.

[0066] Specifically, the positioning rod 83 is symmetrically arranged on the block shaft 41, and the positioning rod 83 is on the outside of the insertion shaft 42. In the default state, the positioning rod 83 has an angle of 45° with the vertical. At the same time, the positioning rod 83 gradually approaches the horizontal plane during the rotation of the insertion shaft 42. The purpose is that the positioning rod 83 will not interfere with the vertical movement of the guide rod 8 in the default state and working state.

[0067] Furthermore, the depths of the plurality of positioning holes 831 are successively reduced (eg Fig. 9 As shown), the purpose is to limit the position of the eccentric mass 4 after axial movement.

[0068] The insertion shaft 42 is driven by the guide rod 8 to move axially and rotate, causing the positioning rod 83 to be pulled out of the current positioning hole 831, and after the guide rod 8 is reset, the rotated positioning rod 83 is inserted into the next positioning hole 831 under the action of the tension spring. The purpose is to fix the eccentric block 4 at the current rotation angle so that the brake shaft 43 drives the eccentric block 4 to open the brake shoe 21, and also to keep the inclined screw groove 82 in the disengaged position of the guide rod 8 after the rotation position is adjusted, so that the guide rod 8 will not change its position when it contacts the matching inclined screw groove 82 again, thereby ensuring the docking accuracy of the guide rod 8 and improving the reliability of the adjustment of the deflection angle of the eccentric block 4.

[0069] As another embodiment further provided by the present invention, a shell ring 7 is slidably disposed on the end surface of the shaft shell 2 and is located outside the brake drum 3 . The shell ring 7 is provided with a protrusion 71 for abutting against the guide rod 8 .

[0070] Specifically, the shaft housing 2 is provided with an annular hole for accommodating the movement of the housing ring 7 , and a circumferentially arranged spring is fixedly installed between the housing ring 7 and the annular hole, and a long hole for accommodating the movement of the protrusion 71 is provided in the annular hole.

[0071] Furthermore, a slope is provided on the protrusion 71, and the end of the guide rod 8 is rounded at the sliding position where it contacts the slope, so that the protrusion 71 pushes the guide rod 8 to move vertically, and a circular plate is fixedly sleeved on the guide rod 8, and a spring arranged in an annular manner on the outside of the guide rod 8 is fixedly installed between the circular plate and the long hole.

[0072] The shell ring 7 is located on the outside of the brake drum 3 to provide shielding and protection for the brake and reduce the intrusion of external dirt into the brake. In the process of the shell ring 7 being received into the ring hole, the inclined surface on the protrusion 71 pushes the guide rod 8 to move vertically, so that the end of the guide rod 8 is inserted into the inclined screw groove 82 for sliding fit, thereby realizing the adjustment of the initial angle of the eccentric block 4.

[0073] As another embodiment further provided by the present invention, a drive ring 5 is movably sleeved on the brake drum 3, and the drive ring 5 is divided into a screw ring 51 and a push-pull ring 52 according to the function;

[0074] The screw ring 51 is threadedly connected to the brake drum 3 and enables the push-pull ring 52 to push the shell push ring 7 to move horizontally.

[0075] Specifically, the push-pull ring 52 slides on the side wall of the brake drum 3, and a circumferentially arranged tension spring is fixedly installed between the screw ring 51 and the push-pull ring 52. The push-pull ring 52 contacts the shell ring 7 in a default state, but the spring on the shell ring 7 is not compressed.

[0076] Furthermore, a rubber damper is installed at the threaded connection position of the screw ring 51 to improve the stability of the screw ring 51 after it stops.

[0077] By rotating the screw ring 51 toward the shell ring 7, the push-pull ring 52 pushes the shell ring 7 to move horizontally, so that the guide rod 8 is pushed and moves vertically. When the screw ring 51 is reversed to return to its original position, the guide rod 8 is reset. This process is repeated to continuously adjust the initial angle of the eccentric block 4. It is easy to use and can be operated on the outside of the brake drum 3. The screw ring 51 with damping is not easily loosened by the rotation of the brake drum 3, thereby ensuring the driving stability of the push-pull ring 52.

[0078] As another embodiment further provided by the present invention, a plurality of arc strips 53 are slidably arranged on the inner wall of the push-pull ring 52, and symmetrically arranged contact blocks 61 are fixedly installed on the arc block 6;

[0079] A trigger rod 531 is fixedly mounted on the arc bar 53 and is in contact with the contacted block 61 , and is used to make the arc block 6 extend out of / retract into the notch 31 .

[0080] Specifically, the number of arc strips 53 corresponds to that of arc blocks 6 , an arc groove for the arc strips 53 to slide is formed on the inner wall of the push-pull ring 52 , and the symmetrically arranged trigger rods 531 are located in the arc-shaped inner circle of the arc strips 53 .

[0081] Furthermore, a sliding hole for the trigger rod 531 to move horizontally is provided on the brake drum 3 , an inclined surface is provided on the contact block 61 , and the end of the trigger rod 531 is slidably matched with the inclined surface.

[0082] When the tricycle is driven on a bumpy road for a long time, the screw ring 51 in the original position is reversed to prompt the push-pull ring 52 to move away from the shell ring 7, so that the trigger rod 531 on the arc bar 53 slides axially and horizontally in the sliding hole, and along with the arc bar 53 sliding in the arc groove, the trigger rod 531 pushes the contact block 61 to move radially, so as to make the arc block 6 extend from the notch 31 and shorten the distance with the middle shoe piece 221, so that the reaction time of the middle shoe piece 221 for deceleration is shorter, thereby enhancing the deceleration effect of the tricycle and ensuring the safety of the tricycle driving on bumpy roads.

[0083] As another embodiment further provided by the present invention, a pressure rod 9 is hingedly provided on the shaft housing 2 , and a shielding member 91 located outside the wire pulling head 44 is provided on the pressure rod 9 .

[0084] Specifically, the shielding member 91 is symmetrically arranged on the pressure rod 9 , and the shielding member 91 is specifically a corrosion-resistant elastic metal sheet. At the same time, a recess for accommodating the movement of the wire pulling head 44 is opened on the outer end surface of the shaft housing 2 , and the recess is arranged opposite to the shielding member 91 .

[0085] The depression on the axle housing 2 provides basic protection for the pull wire head 44, and the cover 91 is used to block the position of the pull wire head 44, effectively reducing the possibility that dirt on the wheel is thrown out by inertia and adheres to the pull wire head 44, causing the knob to corrode and loosen, thereby ensuring the braking effect.

[0086] As another embodiment further provided by the present invention, the guide rod 8 is provided with elastic teeth 81 arranged in an array, and the pressure rod 9 is provided with a limit rod 92 coupled with the elastic teeth 81;

[0087] The reciprocating guide rod 8 causes the elastic teeth 81 to push the limiting rod 92 to deflect, and shortens the distance between the pressure rod 9 and the wire pulling head 44 .

[0088] Specifically, a cavity for accommodating the deflection of the pressure rod 9 is opened on the outer end surface of the shaft housing 2, and the limit rod 92 is fixedly installed at the hinge position of the pressure rod 9, and when the limit rod 92 and the guide rod 8 are in a vertical state, a predetermined distance is maintained between the two.

[0089] Furthermore, a rubber damper is fixedly mounted on the round block at the hinged position of the pressure rod 9 to keep the pressure rod 9 stable after deflection, and the elastic teeth 81 are specifically hook-shaped elastic metal sheets.

[0090] When the guide rod 8 is inserted into the inclined screw groove 82, the arc surface on the elastic tooth 81 slides off the end of the limit rod 92 one by one. When the guide rod 8 is reset, the barbs on the elastic teeth 81 hook and pull the end of the limit rod 92 one by one, so that the limit rod 92 drives the pressure rod 9 to deflect. The purpose is to make the pressure rod 9 contact with the pull wire head 44, to exert pressure on the knob position of the pull wire head 44, to ensure the stability of the knob, and secondly, the covering piece 91 deflected by the pressure rod 9 shortens the distance with the depression, thereby increasing the protective effect of the covering piece 91 on the pull wire head 44.

[0091] As another embodiment further provided by the present invention, the movable protective sheet 63 is in abutment with the guide rod 8 .

[0092] Specifically, the protection groove 631 is connected to the vertical hole in which the guide rod 8 moves, and the side wall of the guide rod 8 is in contact with the protection sheet 63 .

[0093] The protective sheet 63 is pressurized by the deformed capsule 62 so that the protective sheet 63 remains fixed to the guide rod 8, making the guide rod 8 more stable in the horizontal direction when reset. The purpose is that the guide rod 8 can remain fixed to the end of the coupled limit rod 92, so that the deflected pressure rod 9 can stably press the knob on the pull wire head 44, thereby ensuring the working stability of the pull wire head 44.

[0094] Working principle: when the tricycle needs to slow down at high speed, lightly step on the pedal to make the eccentric block 4 open the two brake shoes 21, so that the middle shoe 221 actively approaches the arc block 6 in the rotating state and contacts it, thereby generating sliding friction to slow down the brake drum 3. When it is necessary to slow down or stop again after deceleration, step on the pedal hard to make the middle shoe 221 push the arc block 6 back into the notch 31. At this time, the inner arc surface of the arc block 6 is flush with the inner wall of the brake drum 3, so that the middle shoe 221 contacts the inner wall of the brake drum 3 during the process of contacting the arc block 6, and the side shoe 222 completely contacts the inner wall of the brake drum 3, so that the entire shoe module 22 is in a working state, and the sliding friction generated It is used as the brake drum 3 to brake the wheel, thereby realizing the segmented use of the braking function, and can perform deceleration at high speed and braking after deceleration, effectively reducing the wear on the shoe module 22, and cooperating with the vertically movable guide rod 8 to be inserted into the oblique screw groove 82, and the end of the guide rod 8 slides from the shallow position to the deep position of the oblique screw groove 82, prompting the plug shaft 42 to move axially, and accompanied by the spiral shape of the oblique screw groove 82, to rotate the plug shaft 42, thereby rotating the eccentric block 4, and the purpose of the rotation is to change the pre-angle of the eccentric block 4, thereby changing the opening range of the eccentric block 4 against the brake shoe 21, thereby compensating for the wear of the shoe module 22.

[0095] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An adjustable brake assembly, comprising an axle rod (1) and an axle housing (2) provided with a brake shoe (21), characterized in that: It also comprises a rotatably arranged brake drum (3), wherein the inner wall of the brake drum (3) is circumferentially arranged with notches (31), and an arc block (6) is movably arranged in the notch (31); An eccentric block (4) is rotatably arranged in the axle housing (2) and is used to resist the brake shoe (21) from opening or closing. The brake shoe (21) is provided with a shoe module (22), and the shoe module (22) is divided into a middle shoe (221) and a side shoe (222) according to function. The shoe module (22) is driven by an eccentric block (4) and has the following two working positions: At the first workstation, the arc block (6) is slidably matched with the middle shoe (221); At the second workstation, the middle shoe (221) pushes the arc block (6) to retract the notch (31), and the middle shoe (221) and the side shoe (222) are slidably matched with the inner wall of the brake drum (3).

2. The adjustable brake assembly according to claim 1, characterized in that: A capsule (62) is fixedly installed in the notch (31), the arc block (6) is fixedly connected to the capsule (62), and a protective sheet (63) extending out of the port of the brake drum (3) is fixedly installed on the capsule (62); The arc block (6) in the retracted state squeezes the capsule (62) to deform, and causes the protective sheet (63) to slide against the inner wall of the shaft housing (2).

3. The adjustable brake assembly according to claim 2, characterized in that: A brake shaft (43) for assembling a cable pull head (44) is rotatably arranged on the shaft housing (2), and an insertion shaft (42) movable in the brake shaft (43) is arranged on the eccentric block (4); The insert shaft (42) is provided with an oblique screw groove (82), and a guide rod (8) is movably provided in the shaft housing (2), and the end of the guide rod (8) abuts and slides in the oblique screw groove (82), so as to make the rotation angle of the eccentric block (4) adjustable.

4. The adjustable brake assembly according to claim 3, characterized in that: The insertion shaft (42) is provided with a positioning rod (83), the brake shaft (43) is provided with positioning holes (831) arranged at equal intervals, and the eccentric block (4) in a rotating state causes the positioning rod (83) to be inserted into the positioning holes (831) in sequence.

5. The adjustable brake assembly according to claim 4, characterized in that: A shell ring (7) is slidably arranged on the end surface of the shaft shell (2) and is located outside the brake drum (3). A convex block (71) for contacting and cooperating with the guide rod (8) is arranged on the shell ring (7).

6. The adjustable brake assembly according to claim 5, characterized in that: A drive ring (5) is movably sleeved on the brake drum (3), and the drive ring (5) is divided into a screw ring (51) and a push-pull ring (52) according to its function; The screw ring (51) is threadedly connected to the brake drum (3) and enables the push-pull ring (52) to push against the shell push ring (7) to move horizontally.

7. An adjustable brake assembly according to claim 6, characterized in that: The inner wall of the push-pull ring (52) is slidably provided with a plurality of arc strips (53), and the arc block (6) is fixedly provided with symmetrically arranged contact blocks (61); A trigger rod (531) is fixedly mounted on the arc strip (53) and is in contact with the contacted block (61) and is used to make the arc block (6) extend out of / retract into the notch (31).

8. The adjustable brake assembly according to claim 6, characterized in that: A pressure rod (9) is hingedly provided on the shaft housing (2), and a shielding piece (91) located outside the wire pulling head (44) is provided on the pressure rod (9).

9. An adjustable brake assembly according to claim 8, characterized in that: The guide rod (8) is provided with elastic teeth (81) arranged in an array, and the pressure rod (9) is provided with a limiting rod (92) coupled with the elastic teeth (81); The reciprocating guide rod (8) causes the elastic teeth (81) to push the limit rod (92) to deflect, thereby shortening the distance between the pressure rod (9) and the wire pulling head (44).

10. An adjustable brake assembly according to claim 9, characterized in that: The movable protective sheet (63) is in abutment with the guide rod (8).

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